CA1147458A - Recording system and cassette for such a recording system - Google Patents
Recording system and cassette for such a recording systemInfo
- Publication number
- CA1147458A CA1147458A CA000334760A CA334760A CA1147458A CA 1147458 A CA1147458 A CA 1147458A CA 000334760 A CA000334760 A CA 000334760A CA 334760 A CA334760 A CA 334760A CA 1147458 A CA1147458 A CA 1147458A
- Authority
- CA
- Canada
- Prior art keywords
- cassette
- recording
- detection device
- magnetic tape
- detection
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 238000001514 detection method Methods 0.000 claims abstract description 89
- 230000005291 magnetic effect Effects 0.000 claims abstract description 69
- 230000000875 corresponding effect Effects 0.000 description 10
- 230000003287 optical effect Effects 0.000 description 5
- 230000008901 benefit Effects 0.000 description 4
- 238000010276 construction Methods 0.000 description 4
- 230000002441 reversible effect Effects 0.000 description 4
- 238000000034 method Methods 0.000 description 3
- 238000004804 winding Methods 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000000306 component Substances 0.000 description 2
- XUKUURHRXDUEBC-KAYWLYCHSA-N Atorvastatin Chemical compound C=1C=CC=CC=1C1=C(C=2C=CC(F)=CC=2)N(CC[C@@H](O)C[C@@H](O)CC(O)=O)C(C(C)C)=C1C(=O)NC1=CC=CC=C1 XUKUURHRXDUEBC-KAYWLYCHSA-N 0.000 description 1
- 229940000425 combination drug Drugs 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000010079 rubber tapping Methods 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B15/00—Driving, starting or stopping record carriers of filamentary or web form; Driving both such record carriers and heads; Guiding such record carriers or containers therefor; Control thereof; Control of operating function
- G11B15/005—Programmed access in sequence to indexed parts of tracks of operating tapes, by driving or guiding the tape
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B15/00—Driving, starting or stopping record carriers of filamentary or web form; Driving both such record carriers and heads; Guiding such record carriers or containers therefor; Control thereof; Control of operating function
- G11B15/02—Control of operating function, e.g. switching from recording to reproducing
- G11B15/026—Control of operating function, e.g. switching from recording to reproducing by using processor, e.g. microcomputer
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B23/00—Record carriers not specific to the method of recording or reproducing; Accessories, e.g. containers, specially adapted for co-operation with the recording or reproducing apparatus ; Intermediate mediums; Apparatus or processes specially adapted for their manufacture
- G11B23/38—Visual features other than those contained in record tracks or represented by sprocket holes the visual signals being auxiliary signals
- G11B23/42—Marks for indexing, speed-controlling, synchronising, or timing
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B27/00—Editing; Indexing; Addressing; Timing or synchronising; Monitoring; Measuring tape travel
- G11B27/10—Indexing; Addressing; Timing or synchronising; Measuring tape travel
- G11B27/11—Indexing; Addressing; Timing or synchronising; Measuring tape travel by using information not detectable on the record carrier
- G11B27/13—Indexing; Addressing; Timing or synchronising; Measuring tape travel by using information not detectable on the record carrier the information being derived from movement of the record carrier, e.g. using tachometer
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B27/00—Editing; Indexing; Addressing; Timing or synchronising; Monitoring; Measuring tape travel
- G11B27/10—Indexing; Addressing; Timing or synchronising; Measuring tape travel
- G11B27/34—Indicating arrangements
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B2220/00—Record carriers by type
- G11B2220/90—Tape-like record carriers
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B27/00—Editing; Indexing; Addressing; Timing or synchronising; Monitoring; Measuring tape travel
- G11B27/36—Monitoring, i.e. supervising the progress of recording or reproducing
Abstract
ABSTRACT:
A recording system for recording signals on a magnetic tape comprises a recording apparatus and cas-settes, each containing a specific length of magnetic tape, which cassettes can be placed onto said apparatus, and has a timer by means of which time-preprogrammed automatic recordings can be made.
A detection device determines the maximum time available for recordings with a cassette placed on the recording apparatus and a comparator device compares an output signal of the detection devices with a reference quantity which is derived from the timer and which is a measure of the total time required for the preprogrammed automatic recording(s). When this required time exceeds the maximum time available for recording with this cas-sette, an alarm signal is produced. The cassette is pro-vided with marks which are detected by the detection device and which indicate the length of the magnetic tape con-tained in the cassette being used.
A recording system for recording signals on a magnetic tape comprises a recording apparatus and cas-settes, each containing a specific length of magnetic tape, which cassettes can be placed onto said apparatus, and has a timer by means of which time-preprogrammed automatic recordings can be made.
A detection device determines the maximum time available for recordings with a cassette placed on the recording apparatus and a comparator device compares an output signal of the detection devices with a reference quantity which is derived from the timer and which is a measure of the total time required for the preprogrammed automatic recording(s). When this required time exceeds the maximum time available for recording with this cas-sette, an alarm signal is produced. The cassette is pro-vided with marks which are detected by the detection device and which indicate the length of the magnetic tape con-tained in the cassette being used.
Description
31~1474~3 1 PHO 78.513 The invention relates to a recording system for recording signals on a magnetic tape, which system comprises a recording apparatus and a cassette which con-tains a specific length of magnetic tape and which can be placed onto said apparatus, the recording apparatus com-prising a timer for determining at least one start and one stop instant for an automatic recording which is pre-programmed in respect of time.
Such a known recording system is for example employed for automatically recording television signals, and is described in the magazine "Elektronikschau" 1977, Heft 5, pages 47 to 50. The timer enables a preprogrammed automatic recording to be made within a comparatively long period of time, for example four days. Furthermore, dif- `
15 ferent types of cassettes are available, which differ from ;~
each other in respect of the lengths of magnetic tape.
When preprogramming a recording the user o~ such a record-ing system should ensure that a cassette is used which contains such a length of tape that it can actually accom-modate the entire preprogrammed automatic recording.
It is the object of the invention to improve the ease of operation of a recording system of the type ~; mentioned in the preamble and to exclude~incorrect oper~
ation. To this end the invention is characterized in that the recording apparatus comprises at least one detection : ~.:
':
~ ;8
Such a known recording system is for example employed for automatically recording television signals, and is described in the magazine "Elektronikschau" 1977, Heft 5, pages 47 to 50. The timer enables a preprogrammed automatic recording to be made within a comparatively long period of time, for example four days. Furthermore, dif- `
15 ferent types of cassettes are available, which differ from ;~
each other in respect of the lengths of magnetic tape.
When preprogramming a recording the user o~ such a record-ing system should ensure that a cassette is used which contains such a length of tape that it can actually accom-modate the entire preprogrammed automatic recording.
It is the object of the invention to improve the ease of operation of a recording system of the type ~; mentioned in the preamble and to exclude~incorrect oper~
ation. To this end the invention is characterized in that the recording apparatus comprises at least one detection : ~.:
':
~ ;8
-2- PHO 78.513 device for detecting the recording time attainable with a cassette placed on the apparatus and a comparator device, which controls a warning device for warning the user of the apparatus, which comparator device receives an output quantity from the detection device, which output ~uantity is a measure of the recording time attainable with the cassette, as well as a reference quantity which is derived from the timer and which is a measure of the total auto-matic recording time preprogrammed by means of said timer, the warning device being actuated when the time needed for the preprogrammed automatic recording exceeds the record-ing time attainable with the cassette. In this way the user of the apparatus is automatically warned if a cassette is used which permits a recording period which is shorter than that preprogrammed by means of the timer. Thus erro-neous operation is avoided, which is likely to happen especially if by means of the timer a plurality of succes-sive automatic recordings are preprogrammed, because this may easily give rise to errors in adding the lengths of the individual automatic recordings.
There are several possibilities of realizing such a recording system in respect of the choice of the detection device to be used for detecting the recording period attainable with the cassette inserted in the record ing apparatus; as an example, it is possible to employ optical or mechanical devices for detecting the available length of tape. It is found to be simple and advantageous if the detection device of the apparatus is provided with `
a sensing device for sensing at least one tape-length mark provided on the cassette, which indicates the total length of magnetic tape contained in said cassette. This enables the maximum recording period of this cassette, which is proportional to the total length of the magnetic tape in the cassette, to be determined in a simple manner. It is obvious that a user of the recording apparatus, if several successive aut:omatic recordings are programmed, will use a cassette of which the total length of magnetic tape is still available for recording. In this case it suffices ;
~7~8 PHO 78,513 io compare the sum of the lengths of the preprogrammed automatic recordings with the maximum recording time of the cassette which is used. There are various possi-bilities of realizing a tape-length marking. As an example an optical mark may be used, which is then optically detected. Mechanical tape-length marks in the form of tabs or recesses on the cassette are also possible which are sensed by sensors.
Another possibility is that several marks together in the form of a binary code represent different lengths of magnetic tape.
It is found to be particularly advan-tageous if the detection device of the recording apparatus is adapted to detect the length of tape that is actually available for recording in a cassette placed on the recording apparatus. This ensures that incorrect opera-tion is avoided because allowance is made for the fact that a certain length of magnetic tape in the cassette is no longer available for further recordings bec~llse of previously made recordings. This also enables pre-programmed automatic recordings to be made on cassettes in which already a specific length of magnetic tape is unwound from the~supply reel and is consequently no longer available for further recordings. The detection device may again be realized in various manners and thus be adapted to specific requirements, for which it is pos-sible to revert to the state of the art. As an example the detection device may comprise mechanical or optical means which detect the instantaneous length of magnetic tape contained on the supply reel of the cassette.
~owever, is also possible to provide marks on the magnetic tape itself, enabling the detection device to ascertain at which point on the magnetic tape a new recording begins, so that it is then automatically de-tected how much magnetic tape is still available for recording.
As detection device it is also possible to use a deYice as~for example described in German Offen-legungsschrift 27 30 134 for detecting the length of ~`
, '`
:
.
~ - .. . . .
45~3 PH0 78.513 magnetic tape wound from a supply reel onto a take-up reel of a cassette, which uses the difference in speed of rotation of the supply reel and the take-up reel as detec-tion criterion. Such detection devices should then allow for parameters, such as the total length of magnetic tape the thickness of the magnetic tape and the diameter of the supply-reel and take-up reel hubs.
Preferably, an embodiment of the invention is used, which is characterized in that the recording apparatus comprises a detection device which comprises a combination of first detection device, provided with a sensing device for at least one mark, provided on the cassette, which indicates the total length of magnetic tape contained in said cassette, and a second detection device lS which is adapted to detect the length of magnetic tape which is actually available for recording in a cassette placed on the apparatus, the output quantity of ~he first detection device serving as reference quantity~for the second detection device.
In this way the total length o~ magnetic ~-~
tape in a cassette may also be a variable parameter, which is advantageous in view of the frequently occurring prac~
tical situation that a recording system employs cassettes with different lengths of magnetic tape.~ The total length of magnetic tape is then automatically~;detected by the first detection device and allowance i;s made for this in determining the actual length of magnetic~tape still avail~
able for recordi~g.
Suitably, the detection device used in the recording apparatus is also adapted to determine whether or not a cassette has been inserted in the recording apparatus.
When program~ning an automatic recording, a~;~user of the~
recording apparatus is thus warned immediately if no cas-sette is inserted in the recording apparatus so that the apparatus is consequently not ready for operation.
In respect of a particul~arly simple con~
struction it is found to be advantageous~ f;the record~ng apparatus comprises a microprocessor, which at least serves to constitute the timer, the detection de~ice ::
7~
-5~ PH0 78.513 and the comparator device. By means of such a micropro-cessor a simple compact construction is obtained and the operations required in this respect can be realized in a simple manner.
The invention also relates to a cassette for a recording system in accordance with the invention, which cassette is provided with at least one detectable mark.
In accordance with the invention the cassette is provided with a detectable tape-length mark which indicates the total length of magnetic tape contained in the cassette.
This ensures that an important parameter of the cassette, namely the maximum recording time attainable with said cassette, which time is proportional to the total length of the magnetic tape, can be determined in a simple manner by means of a sensing operation.
Preferably a cassette (which as usually is provided with a cassette housing having two parallel sub-stantially rectangular major walls connected by side walls) is used on which the tape-length marking is provided in a multi-bit binary code, each bit being constituted by a sub-marking, which occurs in one of two specific conditions.
An important advantage of this is that by means of n sub-markings in principle a total of 2n types of cassettes ;
provided with different amounts of magnetic tape can be distinguished from each other. Thus, it is for example possible that in principle a recording system in accordance with the invention can be used in conjunction with eight types of cassettes of different playing times by the use of a 3-bit coded tape-length marking.
It is advantageous if the different types of cassettes, in spite of their different tape-length mark-ings and thus the different amounts of magnetic tape which they contain, can be assembled from each time the same com-ponents. In t:his respect an embodiment of the invention is of interest: which is characterized in that the cassette housing is pro~ided with marking apertures which can be closed by removable wall portions and that one of the two conditions of each sub-marking is constituted by thè pre-'"'"'' ',~'~'~ ' ~7~
-6- PHO 78.513 sence o~ the removable wall portion of a marking aperture and the other of the two conditions by the absence of the removable wall portion. In this embodiment all cassette housings may be assembled using identical components. In order to mark the amount of magnetic tape contained in the cassette one or more of the removable wall portions are removed by means of a very simple tool, in conformity with the binary code used. In view of the space which is available within the cassette it is advantageous if the sub-markings are located near a corner in a major wall of the cassette housing. In this embodiment the space which is available in the cassette between the major walls and the side walls which meet in said corner and the circular reel is used in an optimum manner. An additional advant-age of this embodiment is that especially in recordingequipment in which the cassette is inserted in a movable cassette holder which, together with the cassette contained therein, is subsequently moved to an operating position the tape-length marking of the cassette is arranged at a loca-tion which is suitable to cooperate with the detection device of the recording apparatus. Moreover, the manner in which the part of the cassette with the tape-length marking is moved from and to the detection device by the cassette holder is favourable.
This last-mentioned advantage plays a part in an embodiment of a recording apparatus for a recording sys-tem in accordance with the invention, which is character-ized in that a detection device of the recording apparatus, for determining the amount of magnetic tape which is actu-. .
30 ally available for recording in a cassette placed on the - ~ -~
recording apparatus, is provided with a number, correspond-ing to the number of bits of the binary code of the tape marking, of detection switches, each provided with a spring- ~-loaded movable detection member for detecting the condition ~
35 of a sub-marking on the cassette, which detection member in ~`
the absence oi~ a removable wall portion is at least partly disposed in a marking aperture, the relevant detection switch then being in a first condition, and in the presence `' :~'' ':
'' :~
. ~ , - - . , . :
-~7~
-7- PHO 78.513 of the removable wall portion cooperates with said wall portion, the detection switch then being in a second con-dition. By moving the cassette holder from and towards its operating position the detection members, at least if locally a removable wall portion is present, is moved against the spring load. This can be realized without the use of additional motion-transmitting parts, if in accord-ance with a further embodiment the detection members of the detection switches comprise detection pins which are depressable in their longitudinal directions.
In yet another embodiment no special means are required in order to determine whether or not a cas-sette has been placed on the recording apparatus. This embodiment is characterized in that the detection device is adapted to ascertain that, if all detection switches are in their first condition, no cassette is placed on the recording apparatus. In this embodiment is is obvious that one of the binary words of the binary tape-length marking code should be reserved for other purposes. Thus, when three sub-markings are used this means that seven instead of eight types of cassettes of different playing time may be employed. However, in practice this does not necessarily present a drawback. ~ ~ ~
The invention is described in more detail ~ ;
with reference to the drawings which show two embodiments, ~-to which the invention, however, is not limited.
Figure 1, partly in cross-section, represents ;; a recording system whose recording apparatus comprises a detection device for detecting the total length of the mag-netic tape contained in a cassette.
Figure 2, partly in cross-section, shows a recording system whose recording apparatus comprises two detection devices of which one device detects the total ~ length of the magnetic tape contained in the cassette and ; 35 of which the second device detects the length of magnetic tape in this cassette~which is actually available for recording.
Figure 3 is a perspective~view of a video ~.
7~
-8- PHO 78.513 cassette belonging to a recording system in accordance with the invention.
Fig. 1 shows those parts of a recording sys-tem 1, which are essential for the invention, which system comprises a partly shown recordlng apparatus 2. The record-ing apparatus 2 comprises a cassette receptacle 3 for receiving a cassette 4, which depending on the type of cas-sette contains a different length of magnetic tape.
Fig. 1 shows such a cassette 4 inserted in the receptacle 3 of the recording apparatus, the magnetic tape 5 accommodated in said cassette being symbolically represented by dash-dot lines.
As can be seen in Fig. 1, the cassette 4 is formed with three recesses 7, 8 and 9 in a side wall 6, in which recesses tabs are arranged which may be broken out and which constitute detectable marks. In the present case two tabs 10 and 11 in the two recesses 7 and 9 are left in the cassette 4, whilst the tab corresponding to the recess 8 has been broken out or has not been provided. The tabs 20 serve to indicate the total length of magnetic tape 5 con- -tained in the cassette 4. Each tab may then correspond to a specific length of magnetic tape, so that in the present case three types of cassettes with different lengths of magnetic tape can be distinguished from each other. How-ever, coded combinations of tabs which are present or have been removed may also be used, so that in the case of a binary code a maximum of eight types of cassettes can be distinguished from each other with the present cassette having three tabs. `~
The cassette 4 shown in Fig. 1 can only be inserted in the cassette receptacle 3 in one specific posi-tion, namely so that its wall 6 is positioned on the bottom ~`
12 of the cassette receptacle~ In order to enable record-ings to be made on the magnetic tape 5 in the cassette 4 -contained in the cassette receptacle 3, the apparatus 2 is equipped, in known manner, with a drive arrangement for the transport of the tape, with a scanning device, which for example comprises magnetic recording heads erase heads,~
::
. ,~ ... , . . :
1~'7~5~3 _g_ PHO 78.513 control signal heads etc., for scanning the tape, with amplifier arrangements for amplifying signals to be recorded on the tape, and with further arrangements. For the sake of clarity these arrangements are not shown in Fig. 1, because they are not essential for the invention.
In order to enable all these arrangements to be controlled correctly, to be put into and out of operation, and to switch further functions of the apparatus or the apparatus itself on and off, the recording apparatus 2 is equipped with a control device 13, which in a manner not shown per-forms these control operations, in that it cooperates with the corresponding apparatus parts. For this purpose the control device may comprise electronic or electromagnetic circuit elements, such as switching transistors, electro- -magnets and the like.
The recording apparatus 2 furthermore com-prises a microprocessor 14, to which an input device 16 is connected for the input of instructions via a bus 15 of input lines, which input device is provided, in known man-ner, with a number of switching buttons marked with sym-bols. The control device 13 is connected to the micro-processor 14 via a bus 17 of output lines. Thus it is ensured that instructions applied to the microprocessor 14 by means of the input device 16 via the bus 15 are pro-cessed in said processor, are transferred to the control device 13 in processed form as control signals via the bus 17, which control device 13 controls the recording appara-tus in accordance with the applied instructions, for exam-.
ple for making a recording.
In order to enable a time-preprogrammed recording to be made with the recording apparatus 2, the instant at which the recording is to be started and stopped being determined prior to the actual recording, the appara-tus is provided with a timer. In the present case, the timer is formed by means of the microprocessor 14 which performs the timer functions and in which moreover the start instant and the stop instant of at least one prepro-grammed recording are entered, by means of the input device `
, , :
L7~58 -10- PHO 78.513 1~ and stored. For the optical display of the time instants laid down by the timer a display device 19 is connected to the microprocessor 14 vla a further bus 18 of output lines, which display device comprises three display elements 20, 21 and 22 for displaying the day, the hour and the minutes at which the recording just is to be started or stopped preprogrammed. It is obvious that this display device may also be adapted to display other functions or data; it may also continuously display the time. Bycomparison of the -stored instants with the time setting when the starting instant is reached the microprocessor then ensures that automatically such control signals are supplied to the con-trol device 13 via the bus 17 that the control device causes an automatic recording in the recording apparatus to be started. When the stop instant is reached the micro-processor in a similar way ensures that the previously started recording is again automatically terminated. Thus, the microprocessor performs all the usual functions of a timer, whilst enabling several automatic recordings in suc-cession to be programmed.
In the case of such a time-preprogrammed recording it is obvious that it is only guaranteed that the desired recordingiscompletely recordedon the magnetic tape in a cassetteif the lengthof tape available for recordingis ~ -25 sufficient for this purpose. So far a user of such arecord- ~`
ing system had to make sure that the recording period attain~
able by means of a cassette inserted~1n the apparatus was sufficient to allowa preprogrammed automatic recording to be recorded comp~letely. ~Especially, if~several automatic recordings over a longer period oftime are preprogrammed this is inconvenient and may give rise to incorrect opera-tion.
In order to eliminate this problem the record~
: ~ :
ing apparatus 2 of Fig. 1 comprises a detection device 23 ~or detecting the recording time attainable with a cassette 4 placed on the apparatus and a com~parator device 25 which controls a warning device 24 for warning the user of the apparatus. The comparator device 25 thus receives the out-put quantity of the detection device 23,~which is a measure .: . : . ,, : ~
:. ~
g~
-11- P~IO 78-513 of the recording time attainable with the cassette, at an input 26, for which purpose an output 27 of the detection device 23 is connected to the input 26 of the comparator device 25. Moreover, at a second input 28 the comparator device 25 receives a reference quantity which is derived from the timer constituted by the microprocessor 14 and which is a measure of the total time, determined by means of said microprocessor during which preprogrammed automatic recording is possible, for which purpose a corresponding output 29 of the microprocessor 14 is connected to the input 28 of the comparator device 25 via an output line 30.
To the output 31 of the comparator device 25 the input 32 of the warning device 24 is connected, which in the present example comprises a lamp 33, which lights up if the total time for preprogrammed automatic recording with the appara-tus is greater than the recording time attainable with the ~.
cassette.
In the recording system in accordance with :
Fig. 1 it is assumed that in the case of a time-prepro- :
20 grammed automatic recording suitably a cassette is inserted . .
whose total length of tape is still available for record- :
ing. In practice this requirement is usually:met. There- .
fore, the detection device 23 of the recording apparatus 2 is designed accordingly, which device in the present case comprises a sensing device 34 for the marks provided on the cassette 4, which indicate the length of magnetic tape con~
tained in the cassette and which are constituted by the ~ :
said tabs. The sensing device 34 comprises three slides ;~ 35, 36 and 37, which are guided so as to be: movable perpen~
;~; 30 dicularly to the bottom 12 of the cassette receptacle 3~and : sense the tabs in the cassette, which slides are each urged : :
in the direct:ion of the bottom 12 under the influence of :
springs 39, 43 and 41 respectively which bear against a bracket 38 on the apparatus. The three:slides 35, 36 and 37 are`each p:rovided with a collar 42, 43; or 44 respect-ively, against which the springs 39, 40 and 41, which co-operate with the corresponding slide:, bear. When a cas-sette is inse:rted in the cassette receptacle~3, each sllde ~:. ?' ~1~7~5~
~12- PHO 78-513 35, 36 and 37 bears against the bottom 12 with its collar 42, 43 or 44 under the influence of the springs 39, 40 and 41 which act on said slides, the free ends 45, 46 and 47 of the slides 35, 36 and 37 projecting into the cassette receptacle 3 through the bottom 12. When a cassette has been inserted into the apparatus the slides 35, 36 and 37 are set to a specific position in accordance with the com-bination of tabs which are present or absent, as can be seen in Fig. 1.
lQ For deco~ding the positions of the slides 35, 36 and 37 the detection device 23 is furthermore provided with a decoding device 48, which comprises three switches 49, 50 and 51 which cooperate with the slides 35, 36 and 37. One contact of each switch is connected to a common voltage source V and the other contact of each switch is connected to a resistor 52, 53 and 54 respectively. The `~
ends of the resistors 52, 53 and 54 which are remote from the switches are interconnected and connected to one end of a further resistor 55, whose free end isconnected to earth.
The resistors 52, 53, 54 and the resistor 55 then consti-tute a voltage divider, whose dividing ratio depands on the positions of the switches 49, 50, 51~and thus on the posi-tions of the slides 35, 36, 37 which cooperate with the switches. The dividing ratio of the voltage divider then determines the output quantity of the decoding device 48, which appears on the tapping 56 of the voltage divider and which at the same time constitutes the output quantity~of the detection device 23 which is applied~to the comparator device 25. Thus,~the output quantity o~ the detection device 23, which is determined by the positions of the~
;~ slides defined by the tabs on the cassette, represents a measure, indicated by the tabs on the cassette, of the total length of the tape in the cassette~, so;that said output quantity at the same time represents a measure of the maximum recording time attainable with the cassette~
s is shown~in Figure l~the~two~slides 35 and 37 are set to such a position by the~tw~o tabs 10 and 11 that the switches 49 and 51 which cooperate with the slides : ~ :::
~4'7~
35 and 37 are in the closed positions. However, the slide 36 does not engage with a tab, so that under the influence of the spring 40 which acts on it, it i5 uryed with its free end 46 into the recess 8 formed in the wall 6 of the cassette 4. The switch 50 which cooperates with this slide 36 is then in its open position. Because of this setting of the switches 49, 50 and 51 a specific dividing ratio of the voltage divider 52, 53, 54 and 55 is obtained, which results in a specific output quantity of the detection device 23 on its output 27~ This output quantity is applied to the comparator device 25 via the input 26.
If the user of the present recording system now for example programmes several automatic recordings each with a start instant and a stop instant by means of the timer constituted by the microprocessor 14, the follow-ing process is performed in the apparatus. In the micro-processor the length of each preprogrammed recording is determined and stored, after which the sum of the lengths of all preprogrammed recordings are determined and an out-put quantity is formed corresponding to~said sum. This output quantity of the microprocessor is transferred as ' reference quantity from its output 29 to the input 28 of the comparator device 25 via the output line 30.~ The com-; parator device 25 now compares the quantities applied to its inputs 26 and 28, which are available as electrical signals in analog form,~ and in the case that the maximum recording time attainable with the cassette and determined by the detection device 23 is shorter than the total~length required for the~automatic recordings preprogrammed on the apparatus by means of the timer it supplies a signal to the warning device 24, so that said device is actuated. The ~
lamp 33 of the~warning device 24 then lights up and thus ~ ~ -provides a visual indication to the user that~the program-ming is incorrect. In the present case the comparator device 25 should compare two analog quantities, which can simply be realized by forming their difference.
As states previously, the~slides 35, 36,~ 37;
are each loaded by a spring 39j 40, 41,~which urge each : ~ ~: ~ '`. ,.
7 ~i8 -1~- PHO 78-513 slide with its collar 42, 43 and 44 against the bottom 12 of the cassette receptacle 3 when a cassette is inserted in said receptacle. The slides are then kept in such posi-tions that the switches 49, 50 and 51 of the decoding device 48 which cooperate therewith are all in the open position.
In these switch positions no vo:Ltage appears on the output 27 of the detection device 23 as output quantity, which indicates that no cassette and thus no magnetic tape is available in the apparatus for the purpose of recording.
Thus the output quantity in this case indicates that the available recording time is zero. When in this case the recording system is preprogrammed, the comparator device 25 detects that the available recording time is smaller than required for the preprogrammed automatic recording.
Consequently the warning device 24 is controlled in the previously described manner so that said device provides an optical warning signal with the lamp 33. In this case the detection device 23 is also suitable to detect whether or not a cassette has been inserted in the apparatus.
In the case of a recording system comprising a recording apparatus which accepts different types of cas-settes containing different lengths of magnetic tape, which system enables preprogramming of automatic recordings with the aid of a timer, it is thus ensured, that erroneous pro-gramming of the total time required for the preprogrammed automatic recordings relative to the recording time attain-able with a cassette is virtually avoided. In the case of such an incorrect programming this immediately signalled to the user by an optlcal indication, so that the user may correct the programming or insert a different cassette with a greater recording capacity. The construction of the ~ ;
detection device with a mechanical sensing device for the tabs on the cassette;which serve as mechanical marks ensures a robust and reliable arrangement, which in this case is also .suitable~to detect the presence or absence of a cassette in the apparatus.
The recording system lql shown in Fig. 2 serves for use in conjunction with reversible cassettes.
~: : : : :
5f il -15- P~O 78-513 The recordiny apparatus 10~ compxises a cassette receptacle 103, in which a cassette 104 can be inserted either with a wall 106 or the other wall 157 iEacing the bot-tom.
Depending on the position of the casset-te in the cassette receptacle a recording can be made on each half of a magnetic tape 105. The tape 105 is movable, in known manner, between two reels 158 and 159 which are rota-table in the cassette 104, one of the reels serving as take-up reel and the other as supply reel depending on the position of the cassette in the cassette receptacle. In the situation shown in Fig. 2 the reel 158 for example serves as supply reel and the reel I59 as take-up reel.
For driving the two reels 158 and 159 there are provided two winding mandrils 160 and 161 which are each mounted on a rotatable shaft 162 and 163. For driving each shaft 162 and 163 there are provided a motor 164 and 165 respectively cooperating with said shafts, which via a~switch 166 and 167 respectively are connectable to a motor supply circuit 168 and 169 respectively for the power supply of the motors~
The motor supply circuits 168 and 169 may then take the form of known control circuits for obtaining a specific ; ~-tension in the tape or a specific speed of said tape. The ~
switches 166 and 167, which of course may take the form of ;~b electronic switches, are controlled by a control device 113, as is indicated by the dashed lines in Fig. 2. ; ~;
The cassette 104 has recesses 107, 109 and 170, 171 in its two walls 106 and 157 respectively, in each of which removable tabs 110, 111 and 172, 173 respectively ~
are arranged as mechanically detectable marks. Said tahs ~ ~ ;
again indicate the total length of magnetic tape 105 accom-modated in the casset-te. The provision of said tabs on -both walls 105 and 157 of the cassette enables the detec- ;~
tion of the length of the magnetic tape with the aid of a detection device 123 which comprises a sensing device 134 in both positions of the cassette 104. Obviously, these marks may also be provided on a side wall of the cassette or may take the form of for example optically detectable marks.
-. : .
7~
The detection device 123 of the apparatus shown in Fig. 2 comprises a sensing device 134 and a decod-ing device 148. These devices serve for determining the length of tape contained in the cassette 104. The detection device is also adapted to detect the presence or absence of a cassette in the apparatus. The sensing device 134 com-prises two slides 135 and 137, corresponding to the two tabs 110, 111 and 172, 173 respectively, which vla two switches 149 and 151 of the decoding device 148 produce an output quantity. Each of the outputs 174 and 175 is connected to an input 176 or 177 respectively of the microprocessor 114, which in this case also constitutes the comparator device which processes the output quantities of the decoding device 148.
In addition to the detection device 123 the apparatus shown in Fig. 2 comprisesa second detection device 178, whichisadapted to detect the length of magnetic tape actually availablefor recording inacassette inserted in the apparatus. The output quantityof the firstdetection device 123, which provides an indication about the total length of the magnetic tape contained in the cassette 104, serves as reference quantity for the second detection device 178.
The second detection device 178 comprises two tachogenerators 179 and 180 which are connected to the shafts 162 and 163, which generates on their outputs 1~
and 182 supply an output quantity which is proportional to the speed of the reels 158 and 159 which are coupled to the corresponding tachogenerator 179 or 180 via the shaft 162 or 163 and the winding mandrel 160 or 161 respectively.
Each output 181 or 182 of the tachogenerators 179 and 180 respectively is connected ~o an input 183 or 184 of the microprocessor 114, so that the output quantities of the tachogenerators are applied to the microprocessor, which in the present case is also used for the formation of the ~ ;
35 second detection device. The microprocessor performs the ~ ~
computation required for determining the length of magnetic ~ -tape actually available for recording in the cassette 104.
When a recording is preprogrammed with the input device 116 ,, ~
7~5~3 the microprocessor 114 initiates a brief limited transport of the magnetic tape at a predetermined speed vla the con-trol device 113. As a result o~ this the r~els 158 and 159 are driven and the tachogenerators 179 and 180 supply information about the relevant speeds of the reel 158 and the reel 159 to the microprocessor. With the aid of these quantities and the additionally entered further parameters which are required, such as the diameter of the hubs of the take-up reel and the supply reel, the thickness of the magnetic tape and the total length of the tape, the micro-computer computes the length of tape still contained on the supply reel, which represents the length of tape actually available for recording. This process may for example be effected in a manner as described in detail in German Offenlegungsschrift 27 30 134.
The value supplied by the microprocessor 114, which represents the length of tape carrier actually avail-able for recording is converted into a quantity which cor-responds to an output quantity of the second detection device in the microprocessor. This quantity is again com-pared with the reference quantity which is a measure of the total time required for the automatic recordings prepro-grammed by a user by means of the timer and derived from ~-the data stored in the timer with the aid of the micropro-cessor. This is effected in the microprocessor itself.
The microprocessor thus also performs the function of the ~--comparator device for comprising the two said quantities and supplies a signal corresponding to the result of the comparison on an output 185. The output 185 of the micro-processor 114 is connected to the input 132 of the warning device 124, which in the present case takes the form of an acoustic signal generator. Thus a signal appears on the output 185 of the microprocessor 114 which signal actuates the signal generator 186, if the time required for the pre-programmed automatic recording is greater than the record-ing time attainable with the cassettej which time in the present case is equal to the time corresponding to the length of magnetic tape actually available for recording.
7~5~3 For determining the length o~ magnetic tape actually available for recording, certain cassette para-meters should be entered in-to the microprocessor, as stated previously. These parameters may for example be entered into the microprocessor by the manufacturer, or by the user by means of the input device 116. In the present example one of these parameters, namely the total length of mag-netic tape in a cassette, is automatically entered into the microprocessor by means of the first detection device 123.
10 As stated previously, this is effected by applying the two ~;
output quantities of the first detection device 123 to the microprocessor via its two inputs 176 and 177, said output quantities serving as reference quantities for the second detection device 178 for determining the length of magnetic tape actually available for recording. This step is advan-tageous because the total length of magnetic tape repre-sents a cassette parameter which fxe~uently varies depend-ing on the type of cassette ùsed. The other parameters, ~ ~ -namely the thickness of the tape and the diameter of the reel hubs are generally the same for all cassettes of one recording system. Thus the two last-mentioned parameters ~`~
may be permanently stored in the microprocessor. The vari-able parameter relating to the total~length of the magnetic tape in a cassette is automatically ent~ered into the micro~
processor for each individual cassette.~ ~If desired, other parameters may be indicated on a cassette~in the form of ; detectable marks, which are then detected~by~suitable detection devicesj which in their turn`transfer the infor-; mation detected by means of the marks to~the~micropro~
cessor.
The~ second detection~deviae is constructed so that it may also be~used for determining~whether or not a cassette has been placed in the apparatus. If no cassette is placed on t:he apparatus, the winding mandrel correspond-~` 35 ing to the supply reel remains stationary and thus the tachogenerator connected thereto,~so that said tachogener-ator does not supply an output signal. This situation can be assessed ill the m~icroprocessor, after which said micro~
processor drives the warning device so as to provide a suitable warning signal.
The embodiment of Fig. 2 ensures that incor-rect operation is prevented, even if a cassette is used which is already partly provided with a recording. The time which is actually available for recording is derived from the available length of tape and is compared with the time required for preprogrammed automatic recording selected by a user of the recording system. If no cassette is placed in the apparatus, the user is warned. The use of the microprocessor Eor the formation of the timer, the second detection device as well as the comparator device has the advantage that a very compact and economic con-struction is obtained.
It is obvious that a series of modifications to the embodiments described herein are possible within the scope of the invention. ~his is especially so in respect of the construction of the two detection devices, the com~
parator device and the warning device. As an example, it 20 is also conceivable to design a recording system so that in the case of incorrect programming the comparator device supplies a signal to the control device of the apparatus, which energizes a further device which causes the cassette to be ejected from the apparatus, so that the warning to 25 the user is then constituted by the ejection of the cas-sette from the apparatus. A detection device for detecting the length of magnetic~tape which is actually available for recording may for e~ample also be formed by only one~tacho-generator which is coupled to a reel and by one tachogener-30 ator which detects the speed of transport of the record carrier, in which case the time actually available for automatic recc,rding can be derived from the output quanti-ties of these two tachogenerators.
The reversible video cassette 204 of Fig. 3 ?
35 comprises a cassette housing, of which the Figure shows one plane ma]or wall 206, a side wall comprising two portions 211a and 211b, two reels with reel hubs 212 and 213, a slide 214 and a cover 215 which is pivotable into ~
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~7~S~
-20~ PHO. 78 513A
two directions. sy moving the slide 214 forwards said cover can be closed in order to protect a magnetic tape 205. For a further description of the cassette refer-ence is made to the Applicant's Canadian Patent Applica-tion No. 327,037, filed May 3, 1979 (= PHN 9121). Inthis respect it is to be noted that the cassette is of the reversible type and that a recording on the magnetic tape 205 only covers half the tape width, whilst a record-ing can be made on the other half of the tape width after reversal of the cassette.
Near a corner 216 of the cassette three marking apertures 207-209 are formed in the major wall 206. The marking aperture 208 is provided with a removable wall portion 210. These sub-markings indicate the playing time of the cassette in accordance with a 3-bit binary code, namely-in accordance with the following code in which a "0" means that no removable wall portion is pre-sent and an "x" means that the removable wall portion is still present.
20207 208 ``- ` 209 - playing time.
0 0 0 2 x`30 minutes 0 0 x 2 x 90 "
o ~ 0 2 x 150 " ;
x 0 0 2 x 210 " ~ `
25 x x 0 2 x 60 "
x 0 x 2 x 120 0 x x 2 x 180 x x x 2 x 240 "
As the cassette is reversible three identically coded sub-markings are of course provided in the major wall which in the drawing is disposed on the lower side of `~
the cassette and at a location which after reversal of the cassette coincides with the location of the sub-markings 207-209 shown in the drawing. ~ ~
: ~:
~;
There are several possibilities of realizing such a recording system in respect of the choice of the detection device to be used for detecting the recording period attainable with the cassette inserted in the record ing apparatus; as an example, it is possible to employ optical or mechanical devices for detecting the available length of tape. It is found to be simple and advantageous if the detection device of the apparatus is provided with `
a sensing device for sensing at least one tape-length mark provided on the cassette, which indicates the total length of magnetic tape contained in said cassette. This enables the maximum recording period of this cassette, which is proportional to the total length of the magnetic tape in the cassette, to be determined in a simple manner. It is obvious that a user of the recording apparatus, if several successive aut:omatic recordings are programmed, will use a cassette of which the total length of magnetic tape is still available for recording. In this case it suffices ;
~7~8 PHO 78,513 io compare the sum of the lengths of the preprogrammed automatic recordings with the maximum recording time of the cassette which is used. There are various possi-bilities of realizing a tape-length marking. As an example an optical mark may be used, which is then optically detected. Mechanical tape-length marks in the form of tabs or recesses on the cassette are also possible which are sensed by sensors.
Another possibility is that several marks together in the form of a binary code represent different lengths of magnetic tape.
It is found to be particularly advan-tageous if the detection device of the recording apparatus is adapted to detect the length of tape that is actually available for recording in a cassette placed on the recording apparatus. This ensures that incorrect opera-tion is avoided because allowance is made for the fact that a certain length of magnetic tape in the cassette is no longer available for further recordings bec~llse of previously made recordings. This also enables pre-programmed automatic recordings to be made on cassettes in which already a specific length of magnetic tape is unwound from the~supply reel and is consequently no longer available for further recordings. The detection device may again be realized in various manners and thus be adapted to specific requirements, for which it is pos-sible to revert to the state of the art. As an example the detection device may comprise mechanical or optical means which detect the instantaneous length of magnetic tape contained on the supply reel of the cassette.
~owever, is also possible to provide marks on the magnetic tape itself, enabling the detection device to ascertain at which point on the magnetic tape a new recording begins, so that it is then automatically de-tected how much magnetic tape is still available for recording.
As detection device it is also possible to use a deYice as~for example described in German Offen-legungsschrift 27 30 134 for detecting the length of ~`
, '`
:
.
~ - .. . . .
45~3 PH0 78.513 magnetic tape wound from a supply reel onto a take-up reel of a cassette, which uses the difference in speed of rotation of the supply reel and the take-up reel as detec-tion criterion. Such detection devices should then allow for parameters, such as the total length of magnetic tape the thickness of the magnetic tape and the diameter of the supply-reel and take-up reel hubs.
Preferably, an embodiment of the invention is used, which is characterized in that the recording apparatus comprises a detection device which comprises a combination of first detection device, provided with a sensing device for at least one mark, provided on the cassette, which indicates the total length of magnetic tape contained in said cassette, and a second detection device lS which is adapted to detect the length of magnetic tape which is actually available for recording in a cassette placed on the apparatus, the output quantity of ~he first detection device serving as reference quantity~for the second detection device.
In this way the total length o~ magnetic ~-~
tape in a cassette may also be a variable parameter, which is advantageous in view of the frequently occurring prac~
tical situation that a recording system employs cassettes with different lengths of magnetic tape.~ The total length of magnetic tape is then automatically~;detected by the first detection device and allowance i;s made for this in determining the actual length of magnetic~tape still avail~
able for recordi~g.
Suitably, the detection device used in the recording apparatus is also adapted to determine whether or not a cassette has been inserted in the recording apparatus.
When program~ning an automatic recording, a~;~user of the~
recording apparatus is thus warned immediately if no cas-sette is inserted in the recording apparatus so that the apparatus is consequently not ready for operation.
In respect of a particul~arly simple con~
struction it is found to be advantageous~ f;the record~ng apparatus comprises a microprocessor, which at least serves to constitute the timer, the detection de~ice ::
7~
-5~ PH0 78.513 and the comparator device. By means of such a micropro-cessor a simple compact construction is obtained and the operations required in this respect can be realized in a simple manner.
The invention also relates to a cassette for a recording system in accordance with the invention, which cassette is provided with at least one detectable mark.
In accordance with the invention the cassette is provided with a detectable tape-length mark which indicates the total length of magnetic tape contained in the cassette.
This ensures that an important parameter of the cassette, namely the maximum recording time attainable with said cassette, which time is proportional to the total length of the magnetic tape, can be determined in a simple manner by means of a sensing operation.
Preferably a cassette (which as usually is provided with a cassette housing having two parallel sub-stantially rectangular major walls connected by side walls) is used on which the tape-length marking is provided in a multi-bit binary code, each bit being constituted by a sub-marking, which occurs in one of two specific conditions.
An important advantage of this is that by means of n sub-markings in principle a total of 2n types of cassettes ;
provided with different amounts of magnetic tape can be distinguished from each other. Thus, it is for example possible that in principle a recording system in accordance with the invention can be used in conjunction with eight types of cassettes of different playing times by the use of a 3-bit coded tape-length marking.
It is advantageous if the different types of cassettes, in spite of their different tape-length mark-ings and thus the different amounts of magnetic tape which they contain, can be assembled from each time the same com-ponents. In t:his respect an embodiment of the invention is of interest: which is characterized in that the cassette housing is pro~ided with marking apertures which can be closed by removable wall portions and that one of the two conditions of each sub-marking is constituted by thè pre-'"'"'' ',~'~'~ ' ~7~
-6- PHO 78.513 sence o~ the removable wall portion of a marking aperture and the other of the two conditions by the absence of the removable wall portion. In this embodiment all cassette housings may be assembled using identical components. In order to mark the amount of magnetic tape contained in the cassette one or more of the removable wall portions are removed by means of a very simple tool, in conformity with the binary code used. In view of the space which is available within the cassette it is advantageous if the sub-markings are located near a corner in a major wall of the cassette housing. In this embodiment the space which is available in the cassette between the major walls and the side walls which meet in said corner and the circular reel is used in an optimum manner. An additional advant-age of this embodiment is that especially in recordingequipment in which the cassette is inserted in a movable cassette holder which, together with the cassette contained therein, is subsequently moved to an operating position the tape-length marking of the cassette is arranged at a loca-tion which is suitable to cooperate with the detection device of the recording apparatus. Moreover, the manner in which the part of the cassette with the tape-length marking is moved from and to the detection device by the cassette holder is favourable.
This last-mentioned advantage plays a part in an embodiment of a recording apparatus for a recording sys-tem in accordance with the invention, which is character-ized in that a detection device of the recording apparatus, for determining the amount of magnetic tape which is actu-. .
30 ally available for recording in a cassette placed on the - ~ -~
recording apparatus, is provided with a number, correspond-ing to the number of bits of the binary code of the tape marking, of detection switches, each provided with a spring- ~-loaded movable detection member for detecting the condition ~
35 of a sub-marking on the cassette, which detection member in ~`
the absence oi~ a removable wall portion is at least partly disposed in a marking aperture, the relevant detection switch then being in a first condition, and in the presence `' :~'' ':
'' :~
. ~ , - - . , . :
-~7~
-7- PHO 78.513 of the removable wall portion cooperates with said wall portion, the detection switch then being in a second con-dition. By moving the cassette holder from and towards its operating position the detection members, at least if locally a removable wall portion is present, is moved against the spring load. This can be realized without the use of additional motion-transmitting parts, if in accord-ance with a further embodiment the detection members of the detection switches comprise detection pins which are depressable in their longitudinal directions.
In yet another embodiment no special means are required in order to determine whether or not a cas-sette has been placed on the recording apparatus. This embodiment is characterized in that the detection device is adapted to ascertain that, if all detection switches are in their first condition, no cassette is placed on the recording apparatus. In this embodiment is is obvious that one of the binary words of the binary tape-length marking code should be reserved for other purposes. Thus, when three sub-markings are used this means that seven instead of eight types of cassettes of different playing time may be employed. However, in practice this does not necessarily present a drawback. ~ ~ ~
The invention is described in more detail ~ ;
with reference to the drawings which show two embodiments, ~-to which the invention, however, is not limited.
Figure 1, partly in cross-section, represents ;; a recording system whose recording apparatus comprises a detection device for detecting the total length of the mag-netic tape contained in a cassette.
Figure 2, partly in cross-section, shows a recording system whose recording apparatus comprises two detection devices of which one device detects the total ~ length of the magnetic tape contained in the cassette and ; 35 of which the second device detects the length of magnetic tape in this cassette~which is actually available for recording.
Figure 3 is a perspective~view of a video ~.
7~
-8- PHO 78.513 cassette belonging to a recording system in accordance with the invention.
Fig. 1 shows those parts of a recording sys-tem 1, which are essential for the invention, which system comprises a partly shown recordlng apparatus 2. The record-ing apparatus 2 comprises a cassette receptacle 3 for receiving a cassette 4, which depending on the type of cas-sette contains a different length of magnetic tape.
Fig. 1 shows such a cassette 4 inserted in the receptacle 3 of the recording apparatus, the magnetic tape 5 accommodated in said cassette being symbolically represented by dash-dot lines.
As can be seen in Fig. 1, the cassette 4 is formed with three recesses 7, 8 and 9 in a side wall 6, in which recesses tabs are arranged which may be broken out and which constitute detectable marks. In the present case two tabs 10 and 11 in the two recesses 7 and 9 are left in the cassette 4, whilst the tab corresponding to the recess 8 has been broken out or has not been provided. The tabs 20 serve to indicate the total length of magnetic tape 5 con- -tained in the cassette 4. Each tab may then correspond to a specific length of magnetic tape, so that in the present case three types of cassettes with different lengths of magnetic tape can be distinguished from each other. How-ever, coded combinations of tabs which are present or have been removed may also be used, so that in the case of a binary code a maximum of eight types of cassettes can be distinguished from each other with the present cassette having three tabs. `~
The cassette 4 shown in Fig. 1 can only be inserted in the cassette receptacle 3 in one specific posi-tion, namely so that its wall 6 is positioned on the bottom ~`
12 of the cassette receptacle~ In order to enable record-ings to be made on the magnetic tape 5 in the cassette 4 -contained in the cassette receptacle 3, the apparatus 2 is equipped, in known manner, with a drive arrangement for the transport of the tape, with a scanning device, which for example comprises magnetic recording heads erase heads,~
::
. ,~ ... , . . :
1~'7~5~3 _g_ PHO 78.513 control signal heads etc., for scanning the tape, with amplifier arrangements for amplifying signals to be recorded on the tape, and with further arrangements. For the sake of clarity these arrangements are not shown in Fig. 1, because they are not essential for the invention.
In order to enable all these arrangements to be controlled correctly, to be put into and out of operation, and to switch further functions of the apparatus or the apparatus itself on and off, the recording apparatus 2 is equipped with a control device 13, which in a manner not shown per-forms these control operations, in that it cooperates with the corresponding apparatus parts. For this purpose the control device may comprise electronic or electromagnetic circuit elements, such as switching transistors, electro- -magnets and the like.
The recording apparatus 2 furthermore com-prises a microprocessor 14, to which an input device 16 is connected for the input of instructions via a bus 15 of input lines, which input device is provided, in known man-ner, with a number of switching buttons marked with sym-bols. The control device 13 is connected to the micro-processor 14 via a bus 17 of output lines. Thus it is ensured that instructions applied to the microprocessor 14 by means of the input device 16 via the bus 15 are pro-cessed in said processor, are transferred to the control device 13 in processed form as control signals via the bus 17, which control device 13 controls the recording appara-tus in accordance with the applied instructions, for exam-.
ple for making a recording.
In order to enable a time-preprogrammed recording to be made with the recording apparatus 2, the instant at which the recording is to be started and stopped being determined prior to the actual recording, the appara-tus is provided with a timer. In the present case, the timer is formed by means of the microprocessor 14 which performs the timer functions and in which moreover the start instant and the stop instant of at least one prepro-grammed recording are entered, by means of the input device `
, , :
L7~58 -10- PHO 78.513 1~ and stored. For the optical display of the time instants laid down by the timer a display device 19 is connected to the microprocessor 14 vla a further bus 18 of output lines, which display device comprises three display elements 20, 21 and 22 for displaying the day, the hour and the minutes at which the recording just is to be started or stopped preprogrammed. It is obvious that this display device may also be adapted to display other functions or data; it may also continuously display the time. Bycomparison of the -stored instants with the time setting when the starting instant is reached the microprocessor then ensures that automatically such control signals are supplied to the con-trol device 13 via the bus 17 that the control device causes an automatic recording in the recording apparatus to be started. When the stop instant is reached the micro-processor in a similar way ensures that the previously started recording is again automatically terminated. Thus, the microprocessor performs all the usual functions of a timer, whilst enabling several automatic recordings in suc-cession to be programmed.
In the case of such a time-preprogrammed recording it is obvious that it is only guaranteed that the desired recordingiscompletely recordedon the magnetic tape in a cassetteif the lengthof tape available for recordingis ~ -25 sufficient for this purpose. So far a user of such arecord- ~`
ing system had to make sure that the recording period attain~
able by means of a cassette inserted~1n the apparatus was sufficient to allowa preprogrammed automatic recording to be recorded comp~letely. ~Especially, if~several automatic recordings over a longer period oftime are preprogrammed this is inconvenient and may give rise to incorrect opera-tion.
In order to eliminate this problem the record~
: ~ :
ing apparatus 2 of Fig. 1 comprises a detection device 23 ~or detecting the recording time attainable with a cassette 4 placed on the apparatus and a com~parator device 25 which controls a warning device 24 for warning the user of the apparatus. The comparator device 25 thus receives the out-put quantity of the detection device 23,~which is a measure .: . : . ,, : ~
:. ~
g~
-11- P~IO 78-513 of the recording time attainable with the cassette, at an input 26, for which purpose an output 27 of the detection device 23 is connected to the input 26 of the comparator device 25. Moreover, at a second input 28 the comparator device 25 receives a reference quantity which is derived from the timer constituted by the microprocessor 14 and which is a measure of the total time, determined by means of said microprocessor during which preprogrammed automatic recording is possible, for which purpose a corresponding output 29 of the microprocessor 14 is connected to the input 28 of the comparator device 25 via an output line 30.
To the output 31 of the comparator device 25 the input 32 of the warning device 24 is connected, which in the present example comprises a lamp 33, which lights up if the total time for preprogrammed automatic recording with the appara-tus is greater than the recording time attainable with the ~.
cassette.
In the recording system in accordance with :
Fig. 1 it is assumed that in the case of a time-prepro- :
20 grammed automatic recording suitably a cassette is inserted . .
whose total length of tape is still available for record- :
ing. In practice this requirement is usually:met. There- .
fore, the detection device 23 of the recording apparatus 2 is designed accordingly, which device in the present case comprises a sensing device 34 for the marks provided on the cassette 4, which indicate the length of magnetic tape con~
tained in the cassette and which are constituted by the ~ :
said tabs. The sensing device 34 comprises three slides ;~ 35, 36 and 37, which are guided so as to be: movable perpen~
;~; 30 dicularly to the bottom 12 of the cassette receptacle 3~and : sense the tabs in the cassette, which slides are each urged : :
in the direct:ion of the bottom 12 under the influence of :
springs 39, 43 and 41 respectively which bear against a bracket 38 on the apparatus. The three:slides 35, 36 and 37 are`each p:rovided with a collar 42, 43; or 44 respect-ively, against which the springs 39, 40 and 41, which co-operate with the corresponding slide:, bear. When a cas-sette is inse:rted in the cassette receptacle~3, each sllde ~:. ?' ~1~7~5~
~12- PHO 78-513 35, 36 and 37 bears against the bottom 12 with its collar 42, 43 or 44 under the influence of the springs 39, 40 and 41 which act on said slides, the free ends 45, 46 and 47 of the slides 35, 36 and 37 projecting into the cassette receptacle 3 through the bottom 12. When a cassette has been inserted into the apparatus the slides 35, 36 and 37 are set to a specific position in accordance with the com-bination of tabs which are present or absent, as can be seen in Fig. 1.
lQ For deco~ding the positions of the slides 35, 36 and 37 the detection device 23 is furthermore provided with a decoding device 48, which comprises three switches 49, 50 and 51 which cooperate with the slides 35, 36 and 37. One contact of each switch is connected to a common voltage source V and the other contact of each switch is connected to a resistor 52, 53 and 54 respectively. The `~
ends of the resistors 52, 53 and 54 which are remote from the switches are interconnected and connected to one end of a further resistor 55, whose free end isconnected to earth.
The resistors 52, 53, 54 and the resistor 55 then consti-tute a voltage divider, whose dividing ratio depands on the positions of the switches 49, 50, 51~and thus on the posi-tions of the slides 35, 36, 37 which cooperate with the switches. The dividing ratio of the voltage divider then determines the output quantity of the decoding device 48, which appears on the tapping 56 of the voltage divider and which at the same time constitutes the output quantity~of the detection device 23 which is applied~to the comparator device 25. Thus,~the output quantity o~ the detection device 23, which is determined by the positions of the~
;~ slides defined by the tabs on the cassette, represents a measure, indicated by the tabs on the cassette, of the total length of the tape in the cassette~, so;that said output quantity at the same time represents a measure of the maximum recording time attainable with the cassette~
s is shown~in Figure l~the~two~slides 35 and 37 are set to such a position by the~tw~o tabs 10 and 11 that the switches 49 and 51 which cooperate with the slides : ~ :::
~4'7~
35 and 37 are in the closed positions. However, the slide 36 does not engage with a tab, so that under the influence of the spring 40 which acts on it, it i5 uryed with its free end 46 into the recess 8 formed in the wall 6 of the cassette 4. The switch 50 which cooperates with this slide 36 is then in its open position. Because of this setting of the switches 49, 50 and 51 a specific dividing ratio of the voltage divider 52, 53, 54 and 55 is obtained, which results in a specific output quantity of the detection device 23 on its output 27~ This output quantity is applied to the comparator device 25 via the input 26.
If the user of the present recording system now for example programmes several automatic recordings each with a start instant and a stop instant by means of the timer constituted by the microprocessor 14, the follow-ing process is performed in the apparatus. In the micro-processor the length of each preprogrammed recording is determined and stored, after which the sum of the lengths of all preprogrammed recordings are determined and an out-put quantity is formed corresponding to~said sum. This output quantity of the microprocessor is transferred as ' reference quantity from its output 29 to the input 28 of the comparator device 25 via the output line 30.~ The com-; parator device 25 now compares the quantities applied to its inputs 26 and 28, which are available as electrical signals in analog form,~ and in the case that the maximum recording time attainable with the cassette and determined by the detection device 23 is shorter than the total~length required for the~automatic recordings preprogrammed on the apparatus by means of the timer it supplies a signal to the warning device 24, so that said device is actuated. The ~
lamp 33 of the~warning device 24 then lights up and thus ~ ~ -provides a visual indication to the user that~the program-ming is incorrect. In the present case the comparator device 25 should compare two analog quantities, which can simply be realized by forming their difference.
As states previously, the~slides 35, 36,~ 37;
are each loaded by a spring 39j 40, 41,~which urge each : ~ ~: ~ '`. ,.
7 ~i8 -1~- PHO 78-513 slide with its collar 42, 43 and 44 against the bottom 12 of the cassette receptacle 3 when a cassette is inserted in said receptacle. The slides are then kept in such posi-tions that the switches 49, 50 and 51 of the decoding device 48 which cooperate therewith are all in the open position.
In these switch positions no vo:Ltage appears on the output 27 of the detection device 23 as output quantity, which indicates that no cassette and thus no magnetic tape is available in the apparatus for the purpose of recording.
Thus the output quantity in this case indicates that the available recording time is zero. When in this case the recording system is preprogrammed, the comparator device 25 detects that the available recording time is smaller than required for the preprogrammed automatic recording.
Consequently the warning device 24 is controlled in the previously described manner so that said device provides an optical warning signal with the lamp 33. In this case the detection device 23 is also suitable to detect whether or not a cassette has been inserted in the apparatus.
In the case of a recording system comprising a recording apparatus which accepts different types of cas-settes containing different lengths of magnetic tape, which system enables preprogramming of automatic recordings with the aid of a timer, it is thus ensured, that erroneous pro-gramming of the total time required for the preprogrammed automatic recordings relative to the recording time attain-able with a cassette is virtually avoided. In the case of such an incorrect programming this immediately signalled to the user by an optlcal indication, so that the user may correct the programming or insert a different cassette with a greater recording capacity. The construction of the ~ ;
detection device with a mechanical sensing device for the tabs on the cassette;which serve as mechanical marks ensures a robust and reliable arrangement, which in this case is also .suitable~to detect the presence or absence of a cassette in the apparatus.
The recording system lql shown in Fig. 2 serves for use in conjunction with reversible cassettes.
~: : : : :
5f il -15- P~O 78-513 The recordiny apparatus 10~ compxises a cassette receptacle 103, in which a cassette 104 can be inserted either with a wall 106 or the other wall 157 iEacing the bot-tom.
Depending on the position of the casset-te in the cassette receptacle a recording can be made on each half of a magnetic tape 105. The tape 105 is movable, in known manner, between two reels 158 and 159 which are rota-table in the cassette 104, one of the reels serving as take-up reel and the other as supply reel depending on the position of the cassette in the cassette receptacle. In the situation shown in Fig. 2 the reel 158 for example serves as supply reel and the reel I59 as take-up reel.
For driving the two reels 158 and 159 there are provided two winding mandrils 160 and 161 which are each mounted on a rotatable shaft 162 and 163. For driving each shaft 162 and 163 there are provided a motor 164 and 165 respectively cooperating with said shafts, which via a~switch 166 and 167 respectively are connectable to a motor supply circuit 168 and 169 respectively for the power supply of the motors~
The motor supply circuits 168 and 169 may then take the form of known control circuits for obtaining a specific ; ~-tension in the tape or a specific speed of said tape. The ~
switches 166 and 167, which of course may take the form of ;~b electronic switches, are controlled by a control device 113, as is indicated by the dashed lines in Fig. 2. ; ~;
The cassette 104 has recesses 107, 109 and 170, 171 in its two walls 106 and 157 respectively, in each of which removable tabs 110, 111 and 172, 173 respectively ~
are arranged as mechanically detectable marks. Said tahs ~ ~ ;
again indicate the total length of magnetic tape 105 accom-modated in the casset-te. The provision of said tabs on -both walls 105 and 157 of the cassette enables the detec- ;~
tion of the length of the magnetic tape with the aid of a detection device 123 which comprises a sensing device 134 in both positions of the cassette 104. Obviously, these marks may also be provided on a side wall of the cassette or may take the form of for example optically detectable marks.
-. : .
7~
The detection device 123 of the apparatus shown in Fig. 2 comprises a sensing device 134 and a decod-ing device 148. These devices serve for determining the length of tape contained in the cassette 104. The detection device is also adapted to detect the presence or absence of a cassette in the apparatus. The sensing device 134 com-prises two slides 135 and 137, corresponding to the two tabs 110, 111 and 172, 173 respectively, which vla two switches 149 and 151 of the decoding device 148 produce an output quantity. Each of the outputs 174 and 175 is connected to an input 176 or 177 respectively of the microprocessor 114, which in this case also constitutes the comparator device which processes the output quantities of the decoding device 148.
In addition to the detection device 123 the apparatus shown in Fig. 2 comprisesa second detection device 178, whichisadapted to detect the length of magnetic tape actually availablefor recording inacassette inserted in the apparatus. The output quantityof the firstdetection device 123, which provides an indication about the total length of the magnetic tape contained in the cassette 104, serves as reference quantity for the second detection device 178.
The second detection device 178 comprises two tachogenerators 179 and 180 which are connected to the shafts 162 and 163, which generates on their outputs 1~
and 182 supply an output quantity which is proportional to the speed of the reels 158 and 159 which are coupled to the corresponding tachogenerator 179 or 180 via the shaft 162 or 163 and the winding mandrel 160 or 161 respectively.
Each output 181 or 182 of the tachogenerators 179 and 180 respectively is connected ~o an input 183 or 184 of the microprocessor 114, so that the output quantities of the tachogenerators are applied to the microprocessor, which in the present case is also used for the formation of the ~ ;
35 second detection device. The microprocessor performs the ~ ~
computation required for determining the length of magnetic ~ -tape actually available for recording in the cassette 104.
When a recording is preprogrammed with the input device 116 ,, ~
7~5~3 the microprocessor 114 initiates a brief limited transport of the magnetic tape at a predetermined speed vla the con-trol device 113. As a result o~ this the r~els 158 and 159 are driven and the tachogenerators 179 and 180 supply information about the relevant speeds of the reel 158 and the reel 159 to the microprocessor. With the aid of these quantities and the additionally entered further parameters which are required, such as the diameter of the hubs of the take-up reel and the supply reel, the thickness of the magnetic tape and the total length of the tape, the micro-computer computes the length of tape still contained on the supply reel, which represents the length of tape actually available for recording. This process may for example be effected in a manner as described in detail in German Offenlegungsschrift 27 30 134.
The value supplied by the microprocessor 114, which represents the length of tape carrier actually avail-able for recording is converted into a quantity which cor-responds to an output quantity of the second detection device in the microprocessor. This quantity is again com-pared with the reference quantity which is a measure of the total time required for the automatic recordings prepro-grammed by a user by means of the timer and derived from ~-the data stored in the timer with the aid of the micropro-cessor. This is effected in the microprocessor itself.
The microprocessor thus also performs the function of the ~--comparator device for comprising the two said quantities and supplies a signal corresponding to the result of the comparison on an output 185. The output 185 of the micro-processor 114 is connected to the input 132 of the warning device 124, which in the present case takes the form of an acoustic signal generator. Thus a signal appears on the output 185 of the microprocessor 114 which signal actuates the signal generator 186, if the time required for the pre-programmed automatic recording is greater than the record-ing time attainable with the cassettej which time in the present case is equal to the time corresponding to the length of magnetic tape actually available for recording.
7~5~3 For determining the length o~ magnetic tape actually available for recording, certain cassette para-meters should be entered in-to the microprocessor, as stated previously. These parameters may for example be entered into the microprocessor by the manufacturer, or by the user by means of the input device 116. In the present example one of these parameters, namely the total length of mag-netic tape in a cassette, is automatically entered into the microprocessor by means of the first detection device 123.
10 As stated previously, this is effected by applying the two ~;
output quantities of the first detection device 123 to the microprocessor via its two inputs 176 and 177, said output quantities serving as reference quantities for the second detection device 178 for determining the length of magnetic tape actually available for recording. This step is advan-tageous because the total length of magnetic tape repre-sents a cassette parameter which fxe~uently varies depend-ing on the type of cassette ùsed. The other parameters, ~ ~ -namely the thickness of the tape and the diameter of the reel hubs are generally the same for all cassettes of one recording system. Thus the two last-mentioned parameters ~`~
may be permanently stored in the microprocessor. The vari-able parameter relating to the total~length of the magnetic tape in a cassette is automatically ent~ered into the micro~
processor for each individual cassette.~ ~If desired, other parameters may be indicated on a cassette~in the form of ; detectable marks, which are then detected~by~suitable detection devicesj which in their turn`transfer the infor-; mation detected by means of the marks to~the~micropro~
cessor.
The~ second detection~deviae is constructed so that it may also be~used for determining~whether or not a cassette has been placed in the apparatus. If no cassette is placed on t:he apparatus, the winding mandrel correspond-~` 35 ing to the supply reel remains stationary and thus the tachogenerator connected thereto,~so that said tachogener-ator does not supply an output signal. This situation can be assessed ill the m~icroprocessor, after which said micro~
processor drives the warning device so as to provide a suitable warning signal.
The embodiment of Fig. 2 ensures that incor-rect operation is prevented, even if a cassette is used which is already partly provided with a recording. The time which is actually available for recording is derived from the available length of tape and is compared with the time required for preprogrammed automatic recording selected by a user of the recording system. If no cassette is placed in the apparatus, the user is warned. The use of the microprocessor Eor the formation of the timer, the second detection device as well as the comparator device has the advantage that a very compact and economic con-struction is obtained.
It is obvious that a series of modifications to the embodiments described herein are possible within the scope of the invention. ~his is especially so in respect of the construction of the two detection devices, the com~
parator device and the warning device. As an example, it 20 is also conceivable to design a recording system so that in the case of incorrect programming the comparator device supplies a signal to the control device of the apparatus, which energizes a further device which causes the cassette to be ejected from the apparatus, so that the warning to 25 the user is then constituted by the ejection of the cas-sette from the apparatus. A detection device for detecting the length of magnetic~tape which is actually available for recording may for e~ample also be formed by only one~tacho-generator which is coupled to a reel and by one tachogener-30 ator which detects the speed of transport of the record carrier, in which case the time actually available for automatic recc,rding can be derived from the output quanti-ties of these two tachogenerators.
The reversible video cassette 204 of Fig. 3 ?
35 comprises a cassette housing, of which the Figure shows one plane ma]or wall 206, a side wall comprising two portions 211a and 211b, two reels with reel hubs 212 and 213, a slide 214 and a cover 215 which is pivotable into ~
, ~:'-..
', ' ,.
-;j ~' ~ . ~:
~7~S~
-20~ PHO. 78 513A
two directions. sy moving the slide 214 forwards said cover can be closed in order to protect a magnetic tape 205. For a further description of the cassette refer-ence is made to the Applicant's Canadian Patent Applica-tion No. 327,037, filed May 3, 1979 (= PHN 9121). Inthis respect it is to be noted that the cassette is of the reversible type and that a recording on the magnetic tape 205 only covers half the tape width, whilst a record-ing can be made on the other half of the tape width after reversal of the cassette.
Near a corner 216 of the cassette three marking apertures 207-209 are formed in the major wall 206. The marking aperture 208 is provided with a removable wall portion 210. These sub-markings indicate the playing time of the cassette in accordance with a 3-bit binary code, namely-in accordance with the following code in which a "0" means that no removable wall portion is pre-sent and an "x" means that the removable wall portion is still present.
20207 208 ``- ` 209 - playing time.
0 0 0 2 x`30 minutes 0 0 x 2 x 90 "
o ~ 0 2 x 150 " ;
x 0 0 2 x 210 " ~ `
25 x x 0 2 x 60 "
x 0 x 2 x 120 0 x x 2 x 180 x x x 2 x 240 "
As the cassette is reversible three identically coded sub-markings are of course provided in the major wall which in the drawing is disposed on the lower side of `~
the cassette and at a location which after reversal of the cassette coincides with the location of the sub-markings 207-209 shown in the drawing. ~ ~
: ~:
~;
Claims (13)
THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PRO-PERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A recording system for recording signals on a magnetic tape, which system comprises a recording apparatus and a cassette which contains a specific length of magnetic tape and which can be placed onto said apparatus, the recording apparatus comprising a timer for determining at least one start and one stop instant for an automatic recording which is preprogrammed in respect of time, charac-terized in that the recording apparatus comprises at least one detection device for detecting the recording time attainable with a cassette placed on the apparatus and a comparator device which controls a warning device for warn-ing the user of the apparatus, which comparator device receives an output quantity from the detection device, which output quantity is a measure of the recording time attainable with the cassette, as well as a reference quan-tity which is derived from the timer and which is a measure of the total automatic recording time preprogrammed by means of said timer, the warning device being actuated when the time needed for the preprogrammed automatic recording exceeds the recording time attainable with the cassette.
2. A recording system as claimed in Claim 1, char-acterized in that the detection device of the apparatus is provided with a sensing device for sensing at least one tape-length mark provided on a cassette, which indicates the total length of magnetic tape contained in said cassette.
3. A recording system as claimed in Claim 1, char-acterized in that the detection device of the recording apparatus is adapted to detect the length of tape that is actually available for recording in a cassette placed on the recording apparatus.
4. A recording system as claimed in Claims 2 and 3, characterized in that the recording apparatus com-prises a detection device which comprises a combination of a first detection device, provided with a sensing device for at least one mark, provided on the cassette, PHO. 78-513.
which indicates the total length of magnetic tape contained in said cassette, and a second detection device which is adapted to detect the length of magnetic tape which is actually available for recording in a cassette placed on the apparatus, the output quantity of the first detection device serving as a reference quantity for the second-detection device.
which indicates the total length of magnetic tape contained in said cassette, and a second detection device which is adapted to detect the length of magnetic tape which is actually available for recording in a cassette placed on the apparatus, the output quantity of the first detection device serving as a reference quantity for the second-detection device.
5. A recording system as claimed in Claim 1, char-acterized in that the detection device of the recording apparatus is also adapted to determine whether or not a cassette has been placed on the recording apparatus.
6. A recording system as claimed in Claim 1, char-acterized in that the recording apparatus comprises a microprocessor, which serves at least to form the timer, the detection device and the comparator device.
7. A cassette for a recording system as claimed in Claim 1, which cassette is provided with at least one detectable mark, characterized in that the cassette is pro-vided with a detectable tape-length mark which indicates the length of the magnetic tape contained in the cassette.
8. A cassette as claimed in Claim 7 and provided with a cassette housing having two parallel substantially rectangular major walls interconnected by a side wall, characterized in that the tape length marking is provided on the cassette in a multi-bit binary bode, each bit being constituted by a submarking, which occurs in one of two specific conditions.
9. A cassette as claimed in Claim 7, characterized in that the cassette housing is provided with marking aper-tures which can be closed by removable wall portions and that one of the two conditions of each submarking is con-stituted by the presence of the removable wall portion of a marking aperture and the other of said two conditions by the absence of the removable wall portion.
10. A cassette as claimed in Claim 9, characterized in that the submarkings are located near a corner of a major wall of the cassette housing.
11. A recording apparatus adapted to cooperate PHO. 78-513.
with a cassette as claimed in Claim 9, characterized in that the detection device of the recording apparatus, for determining the amount of magnetic tape which is actually available for recording in a cassette placed on the recording apparatus, is provided with a number, corresponding to the number of bits of the binary code of the tape marking, of detection switches, each pro-vided with a spring-loaded movable detection member for detecting the condition of a sub-marking on the cassette, which detection member in the absence of a removable wall portion is at least partly disposed in a marking aperture, the relevant detection switch then being in a first condition, and in the presence of the removable wall portion cooperates with said wall portion, the detection switch then being in a second condition.
with a cassette as claimed in Claim 9, characterized in that the detection device of the recording apparatus, for determining the amount of magnetic tape which is actually available for recording in a cassette placed on the recording apparatus, is provided with a number, corresponding to the number of bits of the binary code of the tape marking, of detection switches, each pro-vided with a spring-loaded movable detection member for detecting the condition of a sub-marking on the cassette, which detection member in the absence of a removable wall portion is at least partly disposed in a marking aperture, the relevant detection switch then being in a first condition, and in the presence of the removable wall portion cooperates with said wall portion, the detection switch then being in a second condition.
12. A recording apparatus as claimed in Claim 11, characterized in that the detection members of the detec-tion switches comprise detection pins which are depress-able in their longitudinal direction.
13. A recording apparatus as claimed in Claim 11, characterized in that the detection apparatus is adapted to ascertain that, if all detection switches are in their first condition, no cassette is placed on the recording apparatus.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| ATA6341-78 | 1978-09-01 | ||
| AT634178A AT356916B (en) | 1978-09-01 | 1978-09-01 | RECORDING SYSTEM AND CASSETTE FOR SUCH A RECORDING SYSTEM |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1147458A true CA1147458A (en) | 1983-05-31 |
Family
ID=3585333
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000334760A Expired CA1147458A (en) | 1978-09-01 | 1979-08-30 | Recording system and cassette for such a recording system |
Country Status (16)
| Country | Link |
|---|---|
| US (1) | US4339776A (en) |
| JP (1) | JPS5534389A (en) |
| AT (1) | AT356916B (en) |
| AU (1) | AU532078B2 (en) |
| CA (1) | CA1147458A (en) |
| CH (1) | CH649407A5 (en) |
| DE (2) | DE2934225C2 (en) |
| ES (2) | ES483742A1 (en) |
| FR (1) | FR2435097B1 (en) |
| GB (1) | GB2030755B (en) |
| HK (2) | HK21084A (en) |
| IE (1) | IE48936B1 (en) |
| IT (1) | IT1203304B (en) |
| NL (1) | NL179617C (en) |
| SE (2) | SE443469B (en) |
| SG (1) | SG53083G (en) |
Families Citing this family (25)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4398300A (en) * | 1977-12-09 | 1983-08-09 | Staar S. A. | Method and apparatus for cassette identification by operating characteristics |
| BE885102R (en) * | 1978-10-27 | 1980-12-31 | Staar Sa | DEVICE FOR STORING THE INSTANTANEOUS POSITION OF A MAGNETIC STRIP CONTAINED IN A CASSETTE |
| US4406426A (en) * | 1981-06-16 | 1983-09-27 | Richard Crandall | Secrecy-coded cassette |
| JPS5875161A (en) * | 1981-10-29 | 1983-05-06 | Canon Inc | Process kit and image forming device using said kit |
| NL8201573A (en) * | 1982-04-15 | 1983-11-01 | Philips Nv | MAGNETIC TAPE RUNNING. |
| US4554599A (en) * | 1982-06-21 | 1985-11-19 | Fujitsu Ten Limited | Cassette tape reproduction control arrangement |
| JPS61294652A (en) * | 1985-06-20 | 1986-12-25 | Sony Corp | Recording and reproducing device |
| JPS62134856A (en) * | 1985-12-05 | 1987-06-17 | Pioneer Electronic Corp | Digital audio disk reproducing device |
| US4723181A (en) * | 1986-09-24 | 1988-02-02 | Eastman Kodak Company | Tape memory with integral disk index on reel |
| JPS6391884U (en) * | 1986-12-04 | 1988-06-14 | ||
| JP2663425B2 (en) * | 1987-01-20 | 1997-10-15 | 松下電器産業株式会社 | Optical disc player |
| JPS647615U (en) * | 1987-06-30 | 1989-01-17 | ||
| KR910003393Y1 (en) * | 1988-08-26 | 1991-05-24 | 삼성전자 주식회사 | Mode automatic fixing circuit of video tape |
| DE3833452A1 (en) * | 1988-10-01 | 1990-04-05 | Grundig Emv | METHOD FOR PREVENTING ACCIDENTAL OVERWRITING OF VIDEO SIGNAL SECTIONS RECORDED ON VIDEO MAGNETIC TAPE, AND VIDEO MAGNETIC TAPE RECORDER FOR CARRYING OUT THIS METHOD |
| KR910010183B1 (en) * | 1988-12-22 | 1991-12-20 | 삼성전자 주식회사 | Recording stop time setting method |
| JPH0346158A (en) * | 1989-07-14 | 1991-02-27 | Teac Corp | Disk unit |
| GB9011889D0 (en) * | 1990-05-26 | 1990-07-18 | Crowhurst Business Systems | Improvements relating to recording machines |
| EP0501338A3 (en) * | 1991-02-28 | 1994-09-28 | Toshiba Kk | Timer operation management apparatus |
| KR920020481A (en) * | 1991-04-29 | 1992-11-21 | 강진구 | How to automatically change the recording speed of your VCR |
| US5594601A (en) * | 1992-05-27 | 1997-01-14 | Tandy Corporation | Method of programming audio tracks in a sequential medium |
| US5414859A (en) * | 1992-05-27 | 1995-05-09 | Tandy Corporation | Interprocessor communication protocol with built-in error prevention encoding |
| ATE172049T1 (en) * | 1992-07-10 | 1998-10-15 | Koninkl Philips Electronics Nv | SYSTEM FOR RECORDING AND/OR REPRODUCING INFORMATION SIGNALS AND CASSETTE AND DEVICE FOR THE SYSTEM |
| JP3339123B2 (en) * | 1993-08-24 | 2002-10-28 | ソニー株式会社 | Recording information recording method |
| JPH0798935A (en) * | 1993-09-29 | 1995-04-11 | Toshiba Corp | Information signal recording and reproducing device |
| US6101070A (en) * | 1993-09-30 | 2000-08-08 | Sony Corporation | Method and apparatus for determining information and a cassette for use therewith |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3601558A (en) * | 1967-11-20 | 1971-08-24 | Matsushita Electric Ind Co Ltd | Cartridge-type magnetic tape recording and reproducing apparatus with means to indicate the coercivity of the tape |
| US3557360A (en) * | 1968-05-31 | 1971-01-19 | Bell & Howell Co | Apparatus for illuminating the tape reels and spindle splines of tape cassettes |
| US3712559A (en) * | 1969-11-05 | 1973-01-23 | Information Terminals Corp | Tape cassette and improvements therefor |
| AT311693B (en) * | 1971-03-08 | 1973-11-26 | Philips Nv | Recording and / or reproducing device |
| US3723666A (en) * | 1971-03-23 | 1973-03-27 | Bell & Howell Co | Method for distinguishing pauses in recorded features during replay thereof |
| US3761643A (en) * | 1971-07-16 | 1973-09-25 | M Keeler | Video playback unit in inaccessible container |
| US3921215A (en) * | 1973-06-28 | 1975-11-18 | Matsushita Electric Ind Co Ltd | Magnetic recording and reproducing system with tape counter |
| US4075669A (en) * | 1974-03-22 | 1978-02-21 | U.S. Philips Corporation | Index marking for a cassette magazine apparatus |
| AT335195B (en) * | 1974-07-17 | 1977-02-25 | Philips Nv | RECORDING AND / OR PLAYBACK DEVICE AND CASSETTE FOR SUCH DEVICE |
| SE437307B (en) * | 1977-01-17 | 1985-02-18 | Matsushita Electric Ind Co Ltd | TAPE LENGTH INDICATING DEVICE ON TAPE RECORDERS |
| JPS5951054B2 (en) * | 1977-08-25 | 1984-12-12 | ソニー株式会社 | Recording/playback device |
| US4197561A (en) * | 1978-01-18 | 1980-04-08 | Brigham Young University | Portable recorder apparatus for recording time-related data |
-
1978
- 1978-09-01 AT AT634178A patent/AT356916B/en not_active IP Right Cessation
-
1979
- 1979-08-22 NL NLAANVRAGE7906335,A patent/NL179617C/en not_active IP Right Cessation
- 1979-08-24 US US06/069,442 patent/US4339776A/en not_active Expired - Lifetime
- 1979-08-24 DE DE2934225A patent/DE2934225C2/en not_active Expired
- 1979-08-24 DE DE19797924084U patent/DE7924084U1/en not_active Expired
- 1979-08-27 AU AU50320/79A patent/AU532078B2/en not_active Ceased
- 1979-08-28 IT IT68723/79A patent/IT1203304B/en active
- 1979-08-29 GB GB7929923A patent/GB2030755B/en not_active Expired
- 1979-08-29 IE IE1653/79A patent/IE48936B1/en not_active IP Right Cessation
- 1979-08-29 SE SE7907174A patent/SE443469B/en not_active IP Right Cessation
- 1979-08-29 CH CH7846/79A patent/CH649407A5/en not_active IP Right Cessation
- 1979-08-30 ES ES483742A patent/ES483742A1/en not_active Expired
- 1979-08-30 CA CA000334760A patent/CA1147458A/en not_active Expired
- 1979-08-30 ES ES483733A patent/ES483733A1/en not_active Expired
- 1979-08-31 FR FR7921888A patent/FR2435097B1/en not_active Expired
- 1979-08-31 JP JP11054379A patent/JPS5534389A/en active Pending
-
1983
- 1983-08-22 SG SG53083A patent/SG53083G/en unknown
-
1984
- 1984-03-08 HK HK210/84A patent/HK21084A/en not_active IP Right Cessation
- 1984-06-07 HK HK483/84A patent/HK48384A/en not_active IP Right Cessation
-
1985
- 1985-04-11 SE SE8501782A patent/SE8501782L/en not_active Application Discontinuation
Also Published As
| Publication number | Publication date |
|---|---|
| CH649407A5 (en) | 1985-05-15 |
| SG53083G (en) | 1984-04-19 |
| ATA634178A (en) | 1979-10-15 |
| NL179617B (en) | 1986-05-01 |
| ES483742A1 (en) | 1980-09-01 |
| IT7968723A0 (en) | 1979-08-28 |
| FR2435097B1 (en) | 1985-07-12 |
| DE7924084U1 (en) | 1980-07-10 |
| DE2934225A1 (en) | 1980-03-13 |
| GB2030755B (en) | 1983-06-15 |
| NL179617C (en) | 1986-10-01 |
| AU5032079A (en) | 1980-03-27 |
| IT1203304B (en) | 1989-02-15 |
| US4339776A (en) | 1982-07-13 |
| ES483733A1 (en) | 1980-09-01 |
| HK21084A (en) | 1984-03-16 |
| NL7906335A (en) | 1980-03-04 |
| DE2934225C2 (en) | 1985-04-18 |
| IE48936B1 (en) | 1985-06-26 |
| AU532078B2 (en) | 1983-09-15 |
| HK48384A (en) | 1984-06-15 |
| SE7907174L (en) | 1980-03-02 |
| SE8501782D0 (en) | 1985-04-11 |
| GB2030755A (en) | 1980-04-10 |
| JPS5534389A (en) | 1980-03-10 |
| FR2435097A1 (en) | 1980-03-28 |
| AT356916B (en) | 1980-06-10 |
| SE8501782L (en) | 1985-04-11 |
| SE443469B (en) | 1986-02-24 |
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