US 3453388 A
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Description (OCR text may contain errors)
' D. J. NEVILLE TELES CRIBING APPARATUS July 1, 1959 Sheet 013 Filed Aug. 15. 1966 Armin/06 y 1, 1969 D. .1. NEVILLE 3,453,388
I TELESCRIBING APPARATUS I Filed Aug. 15, 1 966 Sheet of 3 INVENTOR fl L/ Amw July 1, 1969 J, v E 3,453,388
TELESCR-IBING APPARATUS Filed Aug. 15, 1966 Sheet 541/7204 W 70 1/51/41 4 ar/[24702 INVENTOR. fizz J/l n/zzz United States Patent 3,453,388 TELESCRIBING APPARATUS Dee J. Neville, Gardena, 'Calif., assignor to Telautograph Corporation, Los Angeles, Calif., a corporation of Virginia Filed Aug. 15, 1966, Ser. No. 572,461
Int. Cl. G08!) /00 US. Cl. 178-18 5 Claims ABSTRACT OF THE DISCLOSURE 'stylus including a switching contact for the controllable means and the receiver stylus linkage is engaged by a stop lug to locate the stylus in a corresponding unison start position. On actuation of said switch, a control signal is developed which energizes said receiver servomotors while said clutch is disengaged to permit accommodation of drift, and after a predetermined time delay of the order of a millisecond, energizes said clutch to couple said servomotor shafts to said styli shafts to permit unison movement of the transmitter and receiver styli.
BACKGROUND OF THE INVENTION Field of the invention This invention relates to telescribing apparatus and, more particularly, to apparatus in a telescribing system for assuring that a pair of remotely located writing styli are disposed in a spatially related unison condition.
Description of the prior art Telescribing systems provide for the transmission between spaced stations of written messages, so that the handwriting of the sender is faithfully reproduced at the receiving station. It is often desired that forms containing blanks for specific information be used in the machines at both stations. In order that the information written in a blank on the form at the sending station will be accurately reproduced in the proper blank at the receiving station, it is necessary that the sending and receiving writing styli at all times be disposed in exactly correlated positions in their respective writing areas. Otherwise a checkmark made on the blank at the sending station may be reproduced at the wrong place on the similar form at the receiving station.
Telescribing systems include amplifiers in the information transmission systems interconnecting the stations. The amplifiers are direct coupled and therefore show drift with time as they are operated. Drift is a change in the amplifier output relative to the amplifier input because of a change in the performance characteristic of the amplifier. In a telescribing system, drift can produce spatial misalignment of the styli. This problem can be avoided by the use of high precision components in the amplifier, but such a solution results in an expensive, often prohibitively expensive, device.
This invention provides simple apparatus for assuring that the writing styli in spaced stations in a telescribing system are in a spatially correlated unison relation when the system is operated. The apparatus whereby this function is obtained is compact and inexpensive. This invention, therefore, provides an economical and accurate telescribing system in which inexpensive amplifiers, not requiring expensive high precision components, may be used. The system is thus especially adapted for use with preprinted forms and the like.
Generally speaking, this invention provides apparatus for assuring that a pair of styli in a telescribing system are positioned at corresponding locations of their respective writing areas. The telescribing system has a transmitter and a receiver. Writing styli are located in the transmitter and the receiver and are mounted for movement over corresponding writing areas. The system includes means responsive to the position of the transmitter stylus for generating an information signal indicative of the position. The system also includes means in the receiver responsive to the information signal for moving the receiving stylus to a corresponding position on the receiver writing area. In such a system, the apparatus provided by this invention includes controllable means for operatively coupling the receiver stylus to its moving means. Means are provided in the transmitter and in the receiver for maintaining the styli in selected corresponding locations when the controllable means is operated to disengage the receiver stylus from its moving means. The apparatus also includes means in the transmitter operable when the transmitter stylus is in its selected location for generating a control signal to which the controllable means is responsive for coupling the receiver stylus to its moving means. The apparatus further includes means for delaying operation of the controllable means to couple the receiver stylus to its moving means for a predetermined time following operation of the control signal generating means.
The above mentioned and other features of the present invention are more fully set forth in the following detailed description of the invention taken in conjunction with the accompanying drawings wherein:
FIG. 1 is an electrical and mechanical schematic diagram of a telescribing system;
FIG. 2 is a fragmentary plan view of the stylus mounting mechanism in the transmitter of the system shown in FIG. 1;
FIG. 3 is a fragmentary plan view of the stylus mounting mechanism in the receiver of the system shown in FIG. 1; and
FIG. 4 is an electrical and mechanical schematic diagram of the telescribing system equipped with the apparatus of this invention.
FIG. 1 shows a telescribing system 10 including a transmitter 11 and a receiver 12. The transmitter includes a writing stylus 13 mounted for movement over a writing area 14 by a stylus mounting mechanism 15. The stylus mounting mechanism preferably is a W-linkage comprised of four pivotally interconnected rigid link members 16-19. Link members 16 and 19 are securely mounted to rotatable shafts 20 and 21, respectively, for pivotal movement about the axes of the shaft. Preferably transmitter writing stylus 13 is a ball point pen, or the like, adapted for manual engagement by a person operating the transmitter. As writing stylus 13 is moved across writing area 14, shafts 20 and 21 are rotated. The instantaneous angular positions of shafts 20 and 21 correspond to the instantaneous position of stylus 13 relative to writing area 14.
The transmitter includes means responsive to rotational movement of shafts 20 and 21 for generating an information signal which is transmitted from the transmitter to the receiver. The receiver contains means responsive to the information signal for causing a writing stylus 35 in the receiver to move to a corresponding position of a receiver writing area 36. Since the angular positions of both of shafts and 21 must be referred to to define the instantaneous position of stylus 13 relative to writing area 14, the information signal generated in the telescribing system has two components, each of which is indicative of the instantaneous position of a respective one of the shafts. Accordingly, transmitter 11 includes information signal generating means 24 comprised of a pair of potentiometers 25 and 26 having their wipers 27, 28 connected to shafts 20 and 21, respectively, for movement along respective potentiometer windings 29 and 30 in response to rotation of the shafts. Suitable potentials are impressed across the potentiometer windings; the potential sources are represented by batteries 31 and 32. The potentials present on the wiper contacts are applied as the inputs to respective ones of a pair of amplifiers 33 and 34, the outputs of which define the information signal of the telescribing system.
Receiver 12 includes a writing stylus 35 mounted for movement relative to a writing area 36 by a stylus mounting mechanism 37. Preferably mechanism 37 is a W-linkage composed of pivotally interconnected rigid link members 3841 mounted between a pair of rotatable shafts 42 and 43. Preferably, writing area 36 and W-linkage 37 are identical in size and geometrical inter-relation to the corresponding aspects of Writing area 14 and W-linkage 15. Shaft 42 is coupled to a shaft 44 of a servomotor 45. The input signal to servomotor 45 is the output of an amplifier 46 which has as its principal input the signal produced by transmitter amplifier 33. A wiper 47 of a potentiometer 48 is connected to shaft 44 for movement along a winding 49 of potentiometer 48 in response to rotation of shaft 44. Potentiometer winding 49 is energized by a suitable source of potential such as a battery 50. Wiper 47 is connected to the input of amplifier 46 by a conductor 51 and supplies the potential present on the wiper contact to the amplifier as a feedback signal indicative of the instantaneous position of shaft 44. Accordingly, a closed servo loop is provided in the receiver for causing shaft 42 to take up an angular position which corresponds to the instantaneous angular position of transmitter shaft 20. A similar closed servo loop is provided in the receiver for causing shaft 43 to take up an angular position which corresponds to the instantaneous angular position of transmitter shaft 21. Shaft 43 is coupled to shaft 52 of a servomotor 53. Motor 53 is controlled by the output of an amplifier 54 which has as its principal input the signal produced by transmitter amplifier 34. A feedback signal generator is coupled between motor 53 and amplifier 54 and includes potentiometer 55 having a winding 56 energized by a potential source 57. A potentiometer wiper 58 is connected to shaft 52 and is also coupled to amplifier 54 via conductor 59.
If any one of amplifiers 33, 34, 46 or 54 shows any drift, the position of stylus 35 in writing area 36 will be different from the position which stylus 13 occupies in wiring area 14. Such a departure from the desired spatial alignment of the styli may lead to unfortunate results, depending upon the criticality of the correspondence of the position of a mark made by stylus 35 to the position of a mark made by stylus 13.
This invention provides a telescribing system which includes apparatus for assuring that the transmitter and receiver styli are in a spatially correlated unison relation when the system is operated. As shown in FIG. 2, transmitter 11 includes a housing 62 over W-linkage 15 which defines a window or aperture 63 around writing area 14. Adjacent one corner of the writing area, the lower lefthand corner, the housing defines a notch 64 which opens to the aperture. When the W-linkage is disposed in the relation shown in FIG. 2, stylus 13 can be rested in notch 64. The notch thus forms a cradle for the stylus and maintains it in a predetermined position relative to writing area 14. The stylus normally is engaged with the notch when the transmitter is not in use. A switch 66 having a push-button operating member 67 is disposed adjacent notch 64 in such a position relative to the cradled position of stylus 13 that the tip of the stylus can be engaged with it without moving the W-linkage.
Preferably, as shown in FIG. 4, the upper end of button 67 defines a recess 68. Preferably the recess has a circular Well 69 in its center, sized to make intimately with the tip of stylus 13. Switch 66 is connected to a control signal generator 70 in the transmitter. Upon closure of the switch, the generator produces a control signal which is transmitted to receiver 12.
Receiver 12 includes means for maintaining stylus 35 in a predetermined position relative to writing area 36 which corresponds exactly to the position which stylus 13 occupies relative to writing area 14 when stylus 13 is in its predetermined position. This means is provided by a stop lug 71 which is engaged on its opposite sides by link members 39 and 40 of W-linkage 37 adjacent the pivotal interconnection of these link members. The W-linkage, when not being operated, is supported on lug 71. Those skilled in the art will understand that the receiver includes a mechanism for lifting stylus 35 away from the writing surface when stylus 13 is not in contact with writing surface 14. This mechanism is operated to lift stylus 35 away from the lug when stylus 13 is lifted from notch 64.
The control signal produced by control signal generator 70 is applied in the receiver to the solenoid 74 of a turn-on relay 75 which operates a pair of normally open switches 76 and 77. The relay also operates a pair of holding contacts (not shown). Switches 76 and 77 are closed upon energization of the winding of solenoid 74. Switch 76 is connected in the receiver so that power is applied to amplifiers 46 and 54 when it is closed. Switch. 77 is a time delay device 78.
A pair of electromagnetic clutches 80 and 81, having energizing field windings 82 and 83, respectively, are located in receiver 12. Clutch 80 is provided for controlling the coupling of W-linkage drive shaft 42 to servomotor shaft 44. Clutch 81 provides a similar function with respect to W-linkage drive shaft 43 and servomotor shaft 52. The clutches are operated to couple the shafts between which they are disposed when their field windings are energized. Energization of the clutch field windings occurs a predetermined time after closure of switch 77 since the windings are connected to the output of time delay device 78.
Telescribing systems 10 has two states of activation when it is turned on. The system is in a stand-by condition when it is turned on and the styli are held in their predetermined positions; this is the condition of the system when no message is being sent. In the stand-by condition of the system, the amplifiers are energized at a low level and no input signals are applied to them. The system also has a ready or transmit condition in which the amplifiers are energized at a higher level and input signals are applied to them. The system is placed in its ready condition by operation of switch 66. Closure of switch 76 in response to operation of turn-on relay 75 increases the energization level of amplifiers 46 and 54.
When transmitter 11 is not in use but the system is in its stand-by condition, stylus 13 is rested in notch 64. Movement of the transmitter stylus into this position causes receiver stylus 35 to be moved into its corresponding position in engagement with stop lug 71. When it is desired to transmit a message, the operator of transmitter 11 grasps pen 13 and engages the tip of the pen in well 69 of push button 67 and depresses the button to operate switch 66. Control signal generator 70 is then operated to transmit a control signal to the receiver where the signal is applied to energize turn-on relay 75 and to close contacts 76 and 77, thereby shifting amplifiers 46 and 54 from their stand-by conditions to their ready conditions. If there is any drift in any of the amplifiers in this system, the shaft servomotors 45 and 53 will be rotated to reflect the drift.
Clutch field windings 82 and 83 are not energized until a predetermined time has elapsed following the closure of contacts 77. Accordingly, the drive shafts for W-linkage 37 are isolated from the servornotors and are not caused to rotate as the shafts rotate to accommodate amplifier drift. After time delay device 78 times out, the clutches are operated to couple the W-linkage drive shafts with the servomotor shafts. The period of delay defined by device 78 preferably is on the order of a millisecond. This short delay period assures that the clutches will be operated before stylus 13 can be removed from engagement with button 66. Accordingly, when stylus 13 is moved from the button, the receiver stylus is operatively coupled to its moving mechanism and moves in exactly the same manner as stylus 13.
There has been described above a simple and effective apparatus for assuring that the transmitter and receiver styli in a telescribing system are disposed in a spatially coordinated unison relation regardless of the presence of drift in any of the amplifiers in the system. Such apparatus enables the use of low cost amplifiers in a precision telescribing system.
What is claimed is:
1. In a telescribing system having:
(i) a transmitter and a receiver,
(ii) writing styli in the transmitter and the receiver mounted on a plurality of pivotally interconnected rigid link members for movement over correspondingly located writing areas,
(iii) means responsive to the position of the transmitter stylus for generating an information signal indicative thereof, and
(iv) means in the receiver responsive to said information signal for moving the receiver stylus to a corresponding position of the receiver writing area,
apparatus for assuring that the styli are positioned at corresponding locations of the respective writing areas comprising:
(a) controllable means for operatively and selectively coupling and decoupling the receiver stylus to its moving means,
(b) receptacle means in the transmitter and a stop lug engaging a link member in the receiver for locating the styli in selected corresponding positons relative to the writing surface when the controllable means is operated to disengage the receiver stylus from its moving means, and
(c) means in the transmitter operable when the transmitter stylus is in said selected position to generate a signal to which the controllable means is responsive for coupling the receiver stylus with its moving means comprising a push button switch associated with the receptacle for the transmitter stylus so as to be engageable by the transmitter stylus.
2. Apparatus according to claim 1 wherein the means for moving the receiver stylus includes a rotatable drive shaft coupled to said link members and a servomotor shaft for rotating said drive shaft and the controllable means comprises a clutch disposed between the servomotor shaft and the receiver stylus rotatable drive shaft operable to couple the stylus to the servomotor shaft for movement of the stylus in response to rotation of the servomotor shaft.
3. In a telescribing system having:
(i) first and second Writing stations,
(ii) writing styli at the first and second stations mounted for movement over correspondingly located writing areas,
(iii) means responsive to the position of the stylus at the first station for generating a control signal indicative thereof,
(iv) means at the second station responsive to said control signal including a feed-back amplifier controlled servomotor for moving the stylus at the second station to a corresponding position of the corresponding writing area, and
(v) means including an amplifier for transmitting said control signal from the first station and for receiving said control signal at the second station,
apparatus for correcting positional misalignment of the styli due to drift in the amplifiers (a) controllable clutch means for operatively engaging and disengaging the stylus at the second station with its moving means,
(b) means at the first and second stations for locating the styli in fixed corresponding positions relative to the writing surface when the clutch means is operated to disengage the stylus at the second station from its moving means,
(c) means at the first station operable when the stylus thereat is in said fixed position to generate a signal to which the clutch means is responsive for engaging the stylus at the second station to its moving means, and
(d) means for delaying operation of the clutch means in engaging the second station stylus to its moving means for a predetermined time of the order of a millisecond following operation of the signal generating means.
5. In a telescribing system having a transmitter and a receiver, writing styli in the transmitter and the receiver mounted on a plurality of pivotally interconnected rigid members for movement over correspondingly located writing areas, means responsive to the position of the transmitter stylus for generating an information signal indicative thereof, and means in the receiver responsive to the information signal for moving the transmitter stylus to a corresponding position on the receiver writing area, apparatus for placing the styli in spatial unison relation so that the position of the receiver stylus relative to the receiver writing area corresponds substantially exactly to the position of the transmitter stylus relative to the transmitter writing area, the apparatus comprising clutch means in the receiver for operatively coupling the receiver stylus to its moving means, stop lug means engaging said link members for maintaining the receiver stylus in a predetermined position relative to the receiver writing area when the clutch means is disengaged, signal generating means in the transmitter for generating a control signal to activate the receiver stylus moving means and to which the clutch means is responsive to engage the clutch, the signal generating means being configured and arranged relative to the transmitter writing area so that the transmitter stylus must be in a position relative to the transmitter writing area when the control signal is generated corresponding to the predetermined position of the receiver stylus, and delay means coupled between the signal generating means and the clutch means for delaying engagement of the clutch means responsive to the control signal until a predetermined time of the order of a millisecond after activation of the receiver stylus moving means.
4. Apparatus according to claim 3 in which said generating means operates to generate a control signal to activate said servomotor during disengagement of said stylus from said servomotor.
References Cited UNITED STATES PATENTS 2,094,039 9/1937 Kinsley 178-19 THOMAS A. ROBINSON, Primary Examiner.
US. Cl. X.R. 178-19