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Publication numberUS3882491 A
Publication typeGrant
Publication dateMay 6, 1975
Filing dateMar 13, 1974
Priority dateMar 13, 1974
Publication numberUS 3882491 A, US 3882491A, US-A-3882491, US3882491 A, US3882491A
InventorsMauch Robert E, Sarbacher Robert I
Original AssigneeBogue John C
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Personal security system
US 3882491 A
Images(4)
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Description  (OCR text may contain errors)

United States Patent 1 [111 3,882,491

Mauch et al. May 6, 1975 1 PERSONAL SECURITY SYSTEM [75] Inventors: Robert E. Mauch, Santa Monica; Primary Examiner-Harold 1 pm Robert I. Sarbacher Marina Del Attorney, Agent, or Fzrm-Wttherspoon and Lane Rey, both of Calif.

[73] Assignee: John C. Bogue, Santa Monica, Calif.

[22] Filed: Mar. 13, 1974 [57] ABSTRACT [21] Appl. No.: 450,878

A distress signaling monitoring system is disclosed. The system includes a plurality of monitoring units 340/409 6 i g Z coupled to a central station by wire or by radio. Each [58] Fie'ld 413 224 monitoring unit relays a distress signal from its locab tion along with location information to direct assistance to the location of the distress signal.

[56] References Cited UNITED STATES PATENTS 19 Claims, 5 Drawing Figures 3,720,911 3/1973 Bomar .4 340/224 X PATENTEB MAY 6 I975 SHEET FNREcE/vER HTR/GGER DETEcToR J 7 1/ F 9 f TIME sTART STOP DATA PULSE DELAY coNTRoL GENERATOR I 1 /5- 17 TIM/N6 PULSE DETEcToR STOPPED sTATE INDICATOR LAMP a DR/vER] TIMING &

. B f' CONTROL 0 SERIAL TO PARALLEL DATA coNvERTER PULSE G p K /6 1a GENERATOR [c FIVE BIT BINARY B/T LAMP LAMP TO /OF 32 DEcoDER STORAGE DR/vER O a k 44 "f/ BIT lfLANR EAN/ DATA 1 I r T T T 1 3 5 25 LDEIVERJ J E PULSE EY/T- FLZM P I LAM P DETTCTOR a '1 -l 9 J'*L B L L L... SYNCHRONlZ/NG i I F PULSE TRANSMITTER- L in I l l {/7 I I I I I (/6 (/8 20 Z BIT LAMP LAMP I5 I I I STORAGE DR/vER 3/ l l l MANUAL RESET FIG. 2.

minno W5 3,882,491

SHEET 2 DATA DETECTOR AND SYNC PULSE 62 32 TRANSM/7TE CPM OCL /5 X DUTY CYCLE 4 SCHMITT 3 TRIGGER POWER SUPPLY 4O HZ SQUARE OCL MNO

FIG. 30.

PAIENIEDMY ems 3,882,491

SHEET 3 MANUA L RESET LAMP 90 DRIVER LAMP DRIVER #2 LAMP DRIVER 3 LAMP DRIVER 4 LAMP DRIVER 5 LAMP DRIVER #6 LAMP 17 l LAMP 2 LAMP 3 LAMP 4 LAMP 5 LAMP 6 LAMP 90 DR/VER#3/ LAMP 3! LAMP 9O DR/VER# LAMP 32 FIG. 3b.

PERSONAL SECURITY SYSTEM BACKGROUND OF THE INVENTION This invention relates to distress signaling systems and. more particularly. to distress signaling systems having a plurality of remote monitoring units and central station apparatus linked to the remote units.

With. unfortunately. increasing frequency people are being attacked in their apartments. apartment hallways. office buildings. public parks. etc. If a person under attack had some convenient and unobvious way of signaling for help, the attacker could be apprehended or at least frightened away thereby saving the attacked person from being robbed. severely beaten or even killed. Many personal signaling devices have been devised and are available on the market today. Unfortunately. many such devices are of such shape and design that the attacker is immediately aware that his victim has such a device and can disarm him before he can signal for help. To overcome this problem some small unobvious signaling devices have been devised. A family ofsuch devices is disclosed in Ser. No. 254.409 filed May 18. 1972 now US. Pat. No. 3.825.833. The devices described in said copending application are small and have the appearance of items commonly carried or worn by a person. Further. these devices are so designed that they can be activated without notice by the attacker. Unfortunately. the devices described in said copending application and similar known devices due to their small size have very limited range. Therefore. in order to increase the range and utility of such devices. relay systems capable of picking up the distress signal and relaying the information to a central location are advantageously utilized. This invention is directed to such a relay system. While this invention has particular utility with the signaling devices described in said copending application. the invention can be used with any such signaling devices. as will be apparent to those skilled in the art.

SUMMARY OF THE INVENTION A system of remote monitoring radio stations serve as a part of a relay link for a distress signal to be sent to a monitoring station from which authorities or help may be dispatched. The monitoring station employs a dispatch board where each of the remote stations is represented by a small light.

An example of this system is described herein where the monitoring display consists of a display of 32 lights and 32 remote units. each of which is associated with one ofthe lights. Each of the remote units and the light representing the remote unit is assigned a unique number from to 31 inclusive. This number is the identification number ofthe remote unit and its corresponding light. In this example. wires are used to connect the remote monitoring units to the central location.

Location with the light display is a special purpose computer which functions as the interface between the lights and the remote stations and is called the master unit. The master unit and the remote units are interconnccted by a single twin line.

Each of the remote units has two states. either triggered or not triggered. When the remote unit is triggered. the associated light and master unit is to be turned on; and if not'triggered. the state of the associated light is to remain unchanged. The necessary communication between each remote unit and its associated light is accomplished over the lines connecting the master unit to the remotes. Since there are 32 remotes and only one pair of lines, multiplexing is used to allow each remote to communicate with its own light. To accomplish this multiplexing, each remote unit is assigned a unique time period during which the remote either does or does not send its identification number to the master unit, depending on the state of the remote unit. If the number is sent. then it is transmitted as a series of pulses which represent a binary number. If the pres ence of a pulse is interpreted as a 1" and the lack of a pulse as a then the sequence of pulses sent by any triggered remote will take the following form: 1, X X X X X where X X X X X are the binary bits of the remote units identification number. If not triggered. a remote unit sends no pulses which under the above definition is 000000. The state of the remote is then clearly indicated by the first bit and the identification number of a triggered unit by the next five bits. Thus, arriving at the master unit we have a series of data groups which indicate which of the remote units have been triggered. The master unit then distributes the information to the light that is associated with each remote unit by sending the first bit of any group of data pulses to the light that is identified by the five bits which follow such a pulse. The master unit performs the additional function of keeping the remote units synchronized so that one and only one remote unit will use the lines at any given time. This synchronization is accomplished by the master unit sending a reference pulse to the remote units. Each remote unit then sends its data at a fixed period of time after it receives the synchronizing pulse. The fixed period of delay for each remote unit is chosen during system set-up such that only one of the remote units will be transmitting data at any given time.

BRIEF DESCRIPTION OF THE DRAWING A complete understanding of the invention can be obtained from the following detailed description when read in conjunction with the annexed drawing in which:

FIG. 1 is a block diagram showing a remote unit constructed in accordance with this invention.

FIG. 2 is a block diagram showing a master unit constructed in accordance with the invention.

FIG. 3a and FIG. 3b together show a detail of an implementation of the logic of a master unit equipped for a maximum of 32 remote units; and

FIG. 4 is a logic diagram of an implementation of a remote unit.

DETAILED DESCRIPTION OF THE INVENTION Referring first to FIG. I, this figure shows in block diagram form a typical remote unit 1 of this invention. A plurality of remote units such as remote unit 1 are located in various areas in which protection is to be provided. For example. remote units could be provided in the hallways of an apartment building. in scattered locations throughout a park. in each apartment unit in an apartment building. at various points along the streets of a city and. in fact. practically in any area where protection is to be provided. As will be apparent, remote unit I is not the primary source of a distress signal but is rather a monitor that picks up a distress signal and relays this signal. along with location information. to a central or master unit.

As shown in FIG. I, remote unit I comprises an FM receiver 3, a trigger detector 5, a time delay device 7, a start-stop control device 9, a data pulse generator El and a timing pulse detector 13. A pair of conductors IS and 17 are coupled to data pulse generator II and timing pulse detector 13. As will be apparent later. conductors 1S and 17 couple remote unit I to the central or master unit 2 shown in FIG. 2. In fact. conductors l5 and 17 couple all the remote units provided in a given system to master unit 2.

FIG. 2 shows, in block diagram form. central or master unit 2. Master unit 2, which is located at a central location from which assistance can be dispatched. is shown in FIG. 2 as being able to accommodate a maximum of 32 remote units such as remote unit I of FIG.

1. As will be apparent, master unit 2 can be designed to accommodate any number of remote units.

As shown in FIG. 2, remote unit 2 comprises a timing and control pulse generator 4, a data pulse detector 6, a synchronizing pulse transmitter 8, a stopped state indicator lamp and driven It a serial to parallel data converter 12, and a five bit binary decoder 14. Since master unit 2 is designed to operate with a maximum of 32 remote units, 32 lamps 20 (only 4 of which are shown: lamps 0, l, 2 and SI) are provided as shown in FIG. 2. Each of the lamps 20 is coupled to a separate lamp driver 18 and a separate one-bit storage device I6 is coupled between each lamp driver 18 and binary decoder 14. In addition, a manual reset device 22 is coupled to all of the one-bit storage devices 16.

Now that the basic elements of a remote unit 1 and the master unit 2 have been described, the operation of the system will be described. With master unit 2., up to 32 remote units such as remote unit 1 can be provided. These remote units could, for example, be located in the hallway (one or more on each floor) in a large apartment building with master unit 2 located in the local police station or in the office of the apartment building if the apartment building has its own security force. The remote units could also be scattered throughout a park with the master unit 2 in a local police station or park guard headquarters, or in practically any other areas. As was mentioned above, master unit 2 can be expanded to accommodate more than 32 remote units; and, of course, the master unit can be designed to handle a number of units less than 32. However, the number of remote units that should be used with a single master unit located at a given central station is limited if the system is to provide useful assistance to a person in immediate danger. The central station must not be located at such a great distance from any remote unit that assistance cannot arrive in time to be of help to the person in distress.

For purposes of this description, assume that 32 re mote units are scattered at key locations, such as hallways, in an apartment complex and that the master unit is located in the local police station. Tenants of the complex desiring the protection afforded by the system would purchase or would be given a distress radio transmitter such as the distress radio transmitter described in said copending application Ser. No. 254,409. The distress transmitter emits a single frequency signal or a narrow frequency band signal. The FM receiver of each remote unit is a very narrow band receiver tuned to the distress transmitter signal. After being tuned during manufacture, the receivers could be locked and sealed in a tamper-proof housing to prevent destruction of the receiver. In fact. all of the components of a remote unit should be housed in a tamper-proof container to protect the unit from vandalism or deliberate destruction. Further. the remote units should be so installed as not to be readily accessible to the general public.

After the remote units are installed, they are all cou pled to master unit 2 by means of conductors I5 and 17. In order to prevent an attempted communication from more than one remote unit to the master at the same time, the master unit provides a timing signal to each remote unit to provide a time slot to each remote unit. A unit cannot transmit to the master except during its time slot as determined by the timing signal and the remote unit. In other words, time division multiplexing of the remote unis is provided. Timing and control pulse generator 4 of master unit 2 provides the timing pulses for the multiplexing. The timing signals provided by generator 4 are applied to synchronizing pulse transmitter 8 which relays these signals to timing pulse 13 via lines 15 and 17. Thus, if none of the remote units receives a distress signal, master unit 2 continuously interrogates each remote unit in timed sequence to check if any remote unit is in a distress signal condition. If none of the remote units is in a distress condition, no signals are received by master unit 2 from a remote unit.

If, now, a tenant or other person equipped with a distress transmitter is attacked, for example. in the second floor hallway of the assumed apartment building he will activate his distress transmitter. The FM receiver of the remote unit in the second floor hallway, or the receiver of the nearest remote unit in this hall if more than one unit is provided, will pick up the distress signal. The FM receiver in the area is constantly monitoring the area for such a distress signal. The FM receiver 3 picking up the distress signal provides a tone burst output to its associated trigger 5. Trigger detector 5 is designed to respond only to such tone burst that exceeds five sec onds. A distress signal from a distress transmitter will cause FM receiver 3 to provide a tone burst having a duration longer than five seconds. By providing this five second response requirement, trigger detector 5 is rendered immune to short noise burst from FM receiver 3. Of course, FM receiver 3 is highly immune to stray noise or stray signals since it is a very narrow band receiver. Thus, the combination of FM receiver 3 and trigger detector 5, designed as described, provide a highly noise immune remote unit.

When the tone burst exceeding five seconds is received by trigger detector 5, trigger detector 5 provides a signal to time delay 7 for the remainder of the tone burst (the tone burst minus five seconds). Time delay 7 delays this signal from detector 5 until the timing signal from master unit 2 is detected by timing pulse detector 13. Upon receipt of the timing signal, detector 13 provides an output to time delay 7 to indicate that the timing pulse was received. The output oftime delay 7 is then further delayed so that an output signal from time delay 7 will be provided to start-stop control 9 at the beginning of the unique time period assigned to that particular remote unit for the transmission of data. The timing signal provided by generator 4 via transmitter 8 of master unit 2 is a two second pulse signal transmitted once each minute. This signal by itself would not provide the unique time slot for each remote unit, but this signal in combination with the further time delays provided by time delay 7 of each remote unit does provide the unique time slot for each unit. Thus, both the timing pulses and the time delay 7 actually provide the multiplexing feature of this invention. Thus. at the time beginning of the unique time period for the remote unit receiving the distress signal, time delay 7 provides a sig nal to start-stop control 9. This signal is a start command signal and start-stop control 9 in response to this command turns on data pulse generator 11 which in turn generates the necessary pulse sequence and places this pulse sequence on lines and 17 to indicate that this particular remote unit has been triggered. When all the data has been sent by data pulse generator 11, data pulse generator 11 generates an additional pulse which is transmitted to start-stop control 9. This additional pulse is a stop command signal which turns off control 9 thereby turning off generator 11.1f none of the other remote units has been triggered, no other data pulses will be transmitted to lines 15 and 17 since the startstop control of each of the other remote units will not have received a start command from the associated time delay. if one or more of the other remote units is triggered. data pulses from the other triggered units will appear on lines 15 and 17 in the time slots for these remote units as determined by the timing pulses from master unit 2 and the time delay for each remote unit.

The data pulses provided by the data pulse generator 11 of the assumed triggered unit are detected by data pulse detector 6 of master unit 2. Data pulse detector 6 constantly monitors lines 15 and 17 for a pulse that has the necessary characteristics to be a data pulse. When detector 6 detects such a pulse. it relays this pulse to timing and control pulse generator 4 via line F and to serial to parallel data converter 12 via line L. The data pulse generator 11 of the triggered remote unit provides a first pulse followed by five data bits. When the first pulse arrives at timing and control pulse generator 4, generator 4 is triggered to generate the necessary pulses and commands to process the five data bits which follow this pulse. Following pulses arriving at timing and control pulse generator 4 do not affect the operation of timing and control generator 4 until the full sequence of commands has been completed. After timing and control generator 4 is triggered by the first pulse from the triggered remote unit, generator 4 provides 5 pulses to serial to parallel data converter 12 via line B. Each of these five pulses from timing and control pulse generator 4 conditions serial to parallel data converter 12 to accept one bit of data from the remote unit via line L and store each of the five data bits in the proper location for subsequent transmission on one of the lines G through K. The stored position of the data bits is determined by whether the bit was the first, second, third, fourth or fifth bit accepted. Thus, at the end of the fifth pulse sent on line B by timing and control generator 4, the five bits of data provide identification of the remote unit that sent the first pulse to timing and control pulse generator 4 to trigger this generator. These five data bits now stored in serial to parallel data converter 12 and the serial to parallel conversion of converter 12 has been accomplished. This stored data is now available on lines G through K.

Continuing its control sequence. timing and control pulse generator now transmits a single pulse to five-bit binary to l to 32 decoder 14 via line C This pulse from timing and control pulse generator 4 causes binary decoder 14 to accept the data available on lines G through K. Binary decoder 14 interprets this data as a binary number that indicates which one of the 32 output lines eminating from binary decoder 14 is to receive a pulse. This pulse is sent on the appropriate line to the one-bit storage device 16 connected to that line. The one-bit storage device receiving this pulse then relays this pulse to its associated lamp driver 18 which in .turn energizes its associated lamp 20. Assume that lamp 2 of the bank of lamps 20 is associated with the remote unit in the second floor hallway of the assumed apartment building. Then, since it was assumed that a person was attacked in the second floor hallway, lamp 2 of the bank of lamps 20 will be lit. The person monitoring master unit 2 will immediately know that someone is in trouble in the second floor hallway of this building and will immediately dispatch assistance.

When the appropriate lamp is lit, timing and control pulse generator 4 ends its sequence with a single pulse on line D. This single pulse on line D erases the infor mation stored in serial to parallel converter 12. Timing and control pulse generator 4 then ceases its control function until it is again triggered by a pulse on line F from a trigger remote unit. However, timing and control pulse generator 4 will continue to provide the tim ing pulses to synchronizing pulse transmitter for transmission to the remote units.

When a lamp 20 has been lit, it will remain energized until it is manually turned off. Manual turn off is accomplished by manual reset 22 which is coupled to all the one-bit storage devices 16. The combination of one-bit storage device 16, lamp drive 18 and lamp 20 forms a bi-stable lamp device that is turned on by the pulse from binary decoder 14 and remains on until turned off by a pulse from manual reset 22. A line A not yet discussed connects timing and control pulse generator to stopped state indicator lamp and driver 10. Line A and stopped state indicator lamp and driver 10 serve no control function. Stopped state indicator and lamp driver 10 include a lamp which may, for example, be a green lamp. This lamp remains on when timing and control pulse generator 4 is not generating a command sequence; or in other words. this lamp is energized when none of the remote units has been triggered. When the lamp of stopped state indicator lamp is extinguished, the operator at master unit 2 is alerted that one of the remote units has been triggered and will immediately scan the lamps 20 to determine which remote unit has sent data bits. Timing and control pulse generator 4 provides a pulse via line A to turn off the lamp of stopped state indicator and driver 10 when it receives a pulse on line F and provides a pulse on line A to turn this lamp back on when it ceases its command sequence.

FIGS. 3a and 3b together show the logic diagrams of a model of a master unit 2 that was constructed as a test model to test the invention. The components utilized belong to the Motorola Semiconductor Products MCO family of digital resistor-transistor logic integrated circuits. Lines M. N. O. P and Q of FIG. 3a connect to lines M. N. O, P and Q respectively of FIG. 3b.

Referring first to FIG. 3a. data detector and sychronizing pulse transmitter 30 correspond to data pulse de tector 6 and synchronizing pulse transmitter 8 of FIG. 2. The oscillator 32 (l CPM OCL) together with the Schmitt trigger 34, the 40 hz. square oscillator 38, the flip-flops 40, 42, 44, 46, 48, 50, 52, 54 and 56 and the NAND gates 58, 60 and 62 make up timing and control pulse generator 4 of FIG. 2. The flip-flops 68, 70, 72, 74 and 76 together with AND gates 78, 80, 82, 84 and 86 make up serial to parallel data converter 12 of FIG. 2; and stopped state converter 12 of FIG. 2 and stopped state indicator lamp and driver 10 of FIG. 2 are made up of ready lamp driver 62 and ready lamp 65 of FIG. 3a. Power supply 36 provides the necessary power to the various components of master unit 2. This power supply can be a battery supply but is preferably a utility supply if one is available. Of course, a standby battery supply could be provided to protect against power failures.

In FIG. 3b there is a direct comparison between some of the components shown in FIG. 2, therefore. these components (the manual reset, the lamp drivers and the lamps) have the same numerals in the two figures. The pair of NOR gates 88 and 90 associated with each of the lamp drivers 18 correspond to the one-bit storage units 16 of FIG. 2; and the NOR gates 92, 94, 96, 98 I00, I02, I04 and 106 make up five-bit binary to l of 32 decoder 14 of FIG. 2.

Similarly, FIG. 4 is a logic diagram of a typical remote unit 1 again using the above mentioned logic circuits. In FIG. 4, the FM receiver 3, of course, corresponds to FM receiver 3 of FIG. 1; and the AC-DC converter (detector) 31 corresponds to trigger detector 5 of FIG. 1. The AND gate 33 together with the delay device 35, the AND gate 37 and the delay device 39 correspond to time delay 7 of FIG. 1. The pair of NOR gates 41 and 43 make up start-stop control 9 of FIG. 1, and the NAND gate 75 is timing pulse detector 13 of FIG. 1. The NAND gate 45 together with the 60 hz.

square wave generator 47, the OR gate 51, the amplifier 53, the OR gate 55, the AND gate 57, the OR gate 59 and flip-flops 61, 63, 65, 67, 69, 71 and 73 constitute data pulse generator 11 of FIG. 1. Power supply 49, of course, supplies the necessary power to the components. Again, this power supply can be a battery supply, but is preferably a utility supply if one is available. Of course, a standby battery supply could also be provided.

From the foregoing description of the invention, it should be obvious that this invention provides an indication of a distress to a central location and indicates the location of the distress. If the remote units are located in defined areas such as individual apartment units, the location indication will be a specific location. If the remote units are located in hallways. parks or the like, the indication is that assistance is needed in the area of the remote unit, each unit being assigned a defined area. The fact that the remote unit will not specifically pinpoint the location in a park, for example, does not detract from the utility of the system. If assistance is summoned to the area, the attacker will soon become aware of the fact that the area is being searched for the victim. In fact, the mere sight ofa policeman in the area of the sound of sirens closing in on the area will, in most instances, be sufficient to frighten the attacker away. While this may make apprehension difficult, the victim is receiving help and this immediate help for the victim is certainly of greater importance than apprehension as such immediate help may save the victims life or at least prevent serious bodily harm to the victim. Further, a search of the area may turn up the attacker after a description is given by the victim. Of course, the person needing assistance may not be one being attacked but may be a person in need of medical help or other assistance. Thus, this invention is not limited to use by persons being attacked.

While the master unit and remote units are described and shown as being coupled by means of a pair of conductors. it should be obvious that a radio link could also be used. The remote unit would be provided with a radio transmitter-receiver to transmit the data to the master unit and to receive timing signals from the master unit. Similarly, the master unit would be provided with a radio transmitter to transmit timing signals to the remote units and a radio receiver to receive data signals from the remote units.

From the foregoing description, it is apparent that this invention provides a system for relaying distress information to a central location from which assistance can be dispatched. Further, the remote units can be provided in almost any location. An entire city could be covered by such remote units with master units scattered at various locations. The master units can be used as described or can be used as a relay to relay information to still another location, or the master can operate devices other than just the indicator lamps. For example, the master unit could operate an audible alarm. a tape recorder or a telephone.

It should also be pointed out that while FIGS. 30. 3b and 4 show logic circuit arrangements that have been tested and have proved highly satisfactory, it will be apparent to those skilled in the art that various changes and modifications can be made to these circuits without departing from the spirit and scope of the invention. Further, it will be obvious to those skilled in the art that various changes and modifications can be made to the circuitry shown in FIGS. 1 and 2 without departing from the spirit and scope of the invention. In this respect, it should be pointed out that the components for which only blocks are shown in the various figures are well known components, and for this reason no specific circuitry or logic diagrams are shown. For that matter, all the specific circuits used in the remote units and the master unit are available on the market. It is the arrangement of these circuits and the manner in which they are utilized together that constitutes the invention as set forth in the claims.

What is claimed is:

l. A distress signal relay system comprising: a plurality of remote units and a master unit coupled to said remote units, said plurality of remote units each including receiving means to receive a radio frequency distress signal and providing an output signal having a time duration greater than a given time duration in response to the receipt of said distress signal, and means responsive to said output signal of said greater duration for generating output data pulses during a given time slot determined by timing pulses received from said master unit by each ofsaid plurality of remote units and said master unit including means to process data pulses from each remote unit, a plurality of lamps at least equal in number to the number of said plurality of remote units, a different one of said plurality of lamps being associated with each of said plurality of remote units, and means coupled between said means to process said data pulses and said lamps for energizing only those lamps for which the corresponding remote unit has received a distress signal.

2. A distress signaling relay system as defined in claim 1 wherein said given duration is five seconds.

3. A distress signaling relay system as described in claim 2 wherein said means for generating data pulses of each said plurality of remote units includes a trigger detector coupled to the output of said receiver means. a time delay device coupled to the output of said trigger detector, a start-stop control device coupled to the output of said time delay device. a data pulse generator coupled to the output of said start-stop control device and a timing pulse detector coupled between said master unit and said time delay device.

4. A distress signal relay system as defined in claim 3 wherein said means to process said data pulses is coupled to the output of said data pulse generator of all of said plurality of remote units.

5. A distress signal relay system as defined in claim 4 wherein said means to process said data pulses includes a timing and control pulse generator coupled to said data pulse generator, a serial to parallel data con verter coupled to said data pulse generator and to said timing and control pulse generator and a binary decoder coupled to said serial to parallel data converter.

6. A distress signal relay system having a plurality of remote units, each said remote unit comprising: a radio receiver for receiving said distress signal, a trigger detector coupled to the output of said radio receiver, a time delay device coupled to the output of said trigger detector, a start-stop control device coupled to the output of said time delay device, a data pulse generator coupled to said start stop control device; a timing pulse detector coupled to said time delay device and coupling means to couple the said timing pulse detector and the said data pulse generator of all of said plurality of remote units to a master unit.

7. A distress signal relay system as defined in claim 6 wherein said master unit comprises a synchronizing pulse transmitter coupled to said coupling means; a data pulse detector coupled to said coupling means; a serial to parallel data converter; a timing and control pulse generator coupled to said synchronizing pulse transmitter, said data pulse detector and said serial to parallel data converter; a binary decoder coupled to said serial to parallel data converter and to said timing and control pulse generator, a plurality of lamps at least equal in number to the number of said plurality of remote units, and individual lamp energizing and deenergizing means coupled between each said plurality of lamps and said binary decoder.

8. A distress signal relay system as defined in claim 7 wherein a manual reset means is coupled to all said lamp energizing and de-energizing means to manually de-energize any energized lamp of said plurality of lamps.

9. A distress signal relay system as defined in claim 8 wherein a stopped state indicator lamp and driver are coupled to said timing and control pulse generator.

10. A distress signal relay system as defined in claim 7 wherein said trigger detector is an AC-DC converter detector.

11. A distress signal relay system as defined in claim 10 wherein said time delay device comprises: a first time delay circuit coupled to said converter detector; a first AND gate having a first input coupled to said time delay circuit. a second input coupled to said converter detector and an output; a second AND gate having a first input coupled to said output of said first AND gate. a second input coupled to said timing pulse detector and an output; and a second time delay circuit coupled between said output of said second AND gate and said start-stop control device.

12. A distress signal device as defined in claim ll wherein said start-stop control device comprises: a first NOR gate having a first input coupled to said second time delay circuit, a second input coupled to said data pulse generator and an output and a second NOR gate having a first coupled to said output of said first NOR gate, a second input coupled to said data pulse generator and an output coupled to said data pulse generator.

13. A distress signal relay system as defined in claim 12 wherein said data pulse generator comprises a NAND gate having first and second inputs and an output, means to couple said first input of said NAND gate to said output of said second NOR gate of said stopstart control device; a square wave generator coupled to said second input of said NAND gate; a plurality of cascaded flip-flop circuits coupled to the output of said NAND gate, a first OR gate having a plurality of inputs and an output; means to couple a different one of said plurality of said flip-flops to each of said plurality of inputs of said first OR gate; an AND gate having first input coupled to said output of said first OR gate, a second input coupled to said second input of said second NOR gate of said start-stop control device and an output; a second OR gate having first input coupled to said output of said AND gate of said data pulse generator. an output coupled to a first input of said timing pulse detector and a second input; means to couple said second input of said second OR gate to said output of said second OR gate; an amplifier having an input coupled to said output of said AND gate of said data pulse generator and an output; a third OR gate having a first input coupled to said output of said amplifier; an output coupled to a second input of said timing pulse detector and a second input and means to couple said second input of said third OR gate to said output of said third OR gate.

14. A distress signal system as defined in claim 13 wherein said timing and control pulse generator comprises a one cycle per minute oscillator coupled to said synchronizing transmitter; a Schmitt trigger; a 40 Hertz square wave oscillator, a plurality of cascaded flip-flops coupled to said 40 Hertz square wave oscillator; a first NAND gate having a plurality of inputs and an output coupled to one of said flip-flops of said plurality of flipflops; means to couple each flip-flop of said plurality of flipflops to a different one of said plurality of inputs of said first NAND gate; a first flip-flop coupled to said data detector and to one of the flip-flops of said plurality of flip-flops; a second NAND gate having a first input coupled to said first flip-flop, a second input coupled to said Schmitt trigger, a third input and an output; a second flip-flop coupled to the output of said second NAND gate; a third flip-flop coupled to said second flip-flop; a fourth flip-flop coupled to said third flipflop; a fifth flip-flop coupled to said fourth flip-flop; means to couple said second, third, fourth and fifth flipfiops to one flip-flop of said plurality of flip-flops; and a third NAND gate having a first input coupled to the common point of said second and third flip-flops, a second input coupled to the common point of said third and fourth flip-flops and a third input coupled to the common point of said fourth and fifth fiip-flops and an output coupled to one of said plurality of inputs of said first NAND gate and to said input of said second NAND gate.

15. A distress signal relay system as defined in claim 14 wherein said serial to parallel data converter comprises: a plurality of cascaded flip-flops; means to couplc the first of said plurality of cascaded flip-flops to said output of said second NAND gate of said timing and control pulse generator; a plurality of cascaded AND gates each having two inputs and an output; means to couple said first input of all of said plurality of AND gates to one flip-flop of said plurality of flipflops of said timing and control pulse generator; means to couple said second input of each of said plurality of AND gates to a different one of said plurality of flipflops of said serial to parallel data converter; and means to couple the output of each of said plurality of AND gates to said five-bit binary decoder.

16. A distress signal relay system as defined in claim 15 wherein said individual means to energize and deenergize said plurality of lamps each comprises: a onebit storage device and a lamp driver coupled between 12 said one-bit device andone of said plurality of lamps. 17. A distress signal relay system as defined in claim 16 wherein said binary decoder comprises a plurality of NAND gates each having a plurality ofinputs and a single output; means to couple the output of each NAND gate of said "plurality of NAND gates to a different one of said one-bit storage devices; means to couple the outputs of said plurality of AND gates of said serial to parallel data converter to a different input of said plurality of inputs of all of said plurality of NAND gates. 18. A distress signal relay device as defined in claim 17 wherein each said one-bit storage device comprises a first and second NOR gate.

19. A distress-signal relay system as defined in claim 18 wherein said means to couple said master unit to all of said plurality of remote units comprises a pair of conductors. g

Patent Citations
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US3720911 *Jun 15, 1971Mar 13, 1973Bomar TMotor vehicle identification and speed control system
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US6980086 *Jul 26, 2002Dec 27, 2005Siemens AktiengesellschaftMethod for operating an anti-theft system for a motor vehicle and an anti-theft system
Classifications
U.S. Classification340/291, 340/524, 340/506, 340/288
International ClassificationG08B25/01
Cooperative ClassificationG08B25/016
European ClassificationG08B25/01D