US2795645A - Transmitter suppressor - Google Patents

Description

`lune 1l, 1957 RQ A. THlENEMANN 2,795,645

TRANSMITTER SUPPRESSOR Filed Sept. 15, 1952 ROLF A. THIENEMANN s my YK?ATTORNEY l United Sttes Patent TnANsMrrTER SUPPRESSOR Rolf A. Thienemann, Chicago, Ill., assiguor to Teletype Corporation, Chicago, lll., a corporation of Delaware Application September 13, 1952, Serial No. 309,598

The portion of the term of the patent subsequent to May 10, 1972 has been discaimed or dedicated to the public 18 Claims. (Cl. 178-17) This invention relates to transmitter Suppressors and more particularly to tape controlled transmitters having means for pre-sensing the tape to accordingly control the suppression of the generation of signals by the transmitter.

In the preparation of permutatively perforated tape for use in telegraph transmitters, errors are often made in the actuation of the means for perforating the tape.

In addition, situations often arise wherein it becomes desirable to cancel a portion of a message already perforated in the tape. In either instancevit is manifest that the unwanted perforations be cancelled. It has become general practice to eiect this cancellation by superimposing over the perforations, desired to be deleted, sets of perforations equal in number to the maximum number of code elements in the particular code employed. Thus, if a six unit code is employed then all six code positions in the tape are perforated to present a set of six perforations which are representative of a rub-out or deletion signal. Obviously it is a wasteful expenditure of transmission time if a tape having a .rub-out signal perforated therein is utilized to actuate a transmitter and the transmitter transmits signals representative of the rub-out or deletion. obtain no information from these signals and furthermore the recipients receiving apparatus such as a reperforator performs a useless recording of these signals.

It is a primary object of the present invention to provide a device operable in conjunction with a transmitter to suppress the transmission of certain predetermined signals.

It is a further object of the invention to provide an auxiliary device for pre-sensing message tape prior to its presentation to the main sensing levers of a tape controlled transmitter and control the operation of the transmitter in accordance with a predetermined set of perforations contained in the message tape.

A more specific object of the invention is to provide a mechanical pre-sensing device to operate a mechanical latching device to control the closing of a shunt circuit for a transmission line upon the pre-sensing device ascertaining a predetermined set of perforations in the tape.

With these and other objects in View the present invention contemplates the use of a standard rotary type transmitter of the general type shown in Teletype Bulletin No, 141, issue 3, issued March 1942, by the Teletype Corporation, Chicago, Illinois. As described in that bulletin the transmitter comprises a commutator ring, a plurality of segments circumferentially spaced about the commutator ring and a constantly rotating brush adapted to successively span the segments of the distributors with the commutator ring. The commutator ring is connected to a signaling line and each of the segments is individually connected to a contact which is controlled by individual sensing levers adapted to be positioned in accordance with perforations contained in a telegraph message tape. The transmitter has a segment not connected to any source of current and when the brush passes over this segment The recipient of the rub-out signals would 2,795,645 Patented June 11, 1957 rice ' sage tape.

More specically, the present invention combines'with the aforedescribcd transmitter an auxiliary tape sensing device adapted to pre-sense each set of permutative apertures prior to presentation to the main sensing levers. Whenever a predetermined permutation of apertures is ascertained in the tape by the auxiliary sensing device, a mechanical latching device is thereby operated. Operation of this device causes a s-hunt circuit to be completed to the transmission line for the purpose of shunting the start segment of the transmitter distributor during the cycle of operation in which the predetermined permutation of apertures is positioned above the main sensing levers.

Other objects and advantages of the present invention will be apparent from the following detailed description when considered in conjunction with the accompanying drawing which discloses a perspective view partially cut away illustrating a transmitting station having included therein an auxiliary sensing device and a mechanical unit controlled thereby embodying the principal features of the invention.

Attention is directed to the drawing, wherein there is disclosed a tape sensing unit generally designated by the reference numeral 1l, which is adapted to receive a message tape l2 Ifrom any well Vknown apparatus for preparing the tape such as a perforato-r or a reperforator. The tape sensing unit ll and the transmitter unit are only described in the present description to an extent necessary to comprehend the present invention because many other tape sensing and transmitting units may be used in conjunction with the present invention. For a more detailed description of the tape sensingand transmitting units the readers attention is directed to the aforeidentitiedTeletype Bulletin No. 141. The tape 12 has formed therein by the perforating apparatus transverse sets of coded permutative apertures 13 each of which is indicative of a signal which is to be transmitted. The code utilized in the present instance is a six unit code, that is, there is a possibility that each set of permutative apertures could consist of six transverse apertures. The tape is further provided with feed holes longitudinally spaced therein.

The tape is advanced through the sensing apparatus by a 4feed wheel lll having mounted on the periphery thereof a plurality of spaced pins adapted to cooperate with the feed holes formed in the tape. The feed'wheel 14 is mounted on a shaft 16 having also mounted thereon a ratchet 17 adapted to be actuated by a spring biased pawl 18 pivotally mounted yon a feed lever i9. The feed lever 19 is periodically oscillated to advancethe pawl 14l over the teeth of the ratchet ll7 by means of a cyclically operable bail 2l. pivotally mounted on a rod 22. Depending from the bail 21 and integrally formed therewith is an arm 23 adapted to be engaged by an adjustable screw 24 which in turn is threadably mounted Within an upturned end 25 of a cam follower 26. The follower 26 is pivotally mounted on a pin 27 and has rotatably mounted on its opposite end a roller 28 adapted to follow the periphery of a cam 29 xed to and adapted to rotate with a shaft 31.

Mounted on the shaft 31 is a friction clutch 32 adapted to interconnect the shaft 31 with a spur gear 33. Engaging the spur gear 33 is a worm 34 connected to and driven by a continuously operating electrical motor 36. Secured to the shaft 31 is a disc 37 having extending therefrom a stop lug 38 adapted to cooperate with a pivotally mounted stop lever 39. Controlling the position of the stop lever 39 is an electric magnet 41 adapted to be energized through an obvious circuit including a manually operable switch 42. Closure of the switch 42 completes the circuit for energizing the electric magnet 41 and as a consequence the stop lever 39 is withdrawn from engagement with the stop lug 38 to permit rotative power to be transmitted from the motor 36, through the worm 34, through the spur gear 33, and through the clutch 32 to the shaft 31.

A transmitting unit generally designated by the reference number 43 comprises a commutator ring 44, connected to a transmission line 45, and a plurality of circumferentially spaced segments 46 to 53, inclusive. The segments 47 to 52, inclusive, are connected by leads 54 to individual contacts 56. The segment 53 is connected by a lead 57 to a conductive pivot rod 58 which in turn is connected to ground. The segment 46 has no leads running therefrom. Secured to the upper extremity of the rotating shaft 31 is `a brush 59 adapted to successively span the commutator ring 44 and each of the segments 46 to 53, inclusive, during rotation of the shaft 31.

Associated with each of the contacts 56 are individual spring biased contact arms 61 pivotally mounted about the conductive pivot rod 58. The positions assumed by the spring biased contact arms 61 are controlled through the instrumentality of individual sensing levers 62 mounted in a pivoted fashion about a shaft 63. lEach sensing lever 62 is urged by Va spring 64 to move in a counterclockwise direction about the-shaft 63, however, such movement is prevented by an extension 66 formed integral with each sensing lever which is adapted to be engaged and held in position by the bail 21. ln addition each sensing lever is provided at its free end with a sensing pin 67 adapted to probe and ascertain the presence of any apertures 13 in register with the pins 67.

Turning now to a consideration of the elements cornprising the present invention, there is provided a frame 69 pivotally mounted about a pivot shaft 71. A portion of the frame 69 is upturned to provide a support 72 for mounting, in a transverse row, six sensing pins 73. The position of the frame 69 is maintained through the instrumentality of an articulated linkage including a link 74 pivotally mounted to an intermediate operating lever 76 rotatably mounted on a pivot stud 77. Urging the lever 76 in a counterclockwise direction is an extended tension spring 78, however, the lever 76 is precluded from movement by an extension 79 formed integral therewith engaging an adjusting screw 81 positioned Within a threaded aperture formed in an upturned end 82 of a cam follower arm 83. The cam follower arm 83 is pivotally mounted on a stud shaft 84 `and has mounted in the vicinity of its terminus a roller 86. Connected to the arm 33 is a spring 87 which is extended to apply a force to the arm 83 to hold the roller 86 in engagement with a cam S8 secured to the shaft 31.

Pivotally connected to the frame 69 is a latch arm 91 recessed to provide a notch 92 therein. Positioned in transverse alignment with the latch arm 91 is a second latch arm 93 pivotally mounted about a pivot rod 94 and having formed therein a notch 96 also in transverse alignment with the notch 92. Overlying the latch arms 91 and 93 is a bent-over portion 97 of a spring biased arm 98 pivotally mounted about a stud 99. Securely fastened to the arm '98 is 'an actuator 100 adapted to cooperate with a normally open contact 101. The contact 101 upon closure is adapted to complete a shunt circuit for the transmission line 45 which may be traced from ground, through the contact 101, over a lead 102, to the transmission line 45 and from there to a pair of receiving magnets 103 located at a receiving station 104, thence through a switch 105, through a battery 106, to ground.

Rotatively mounted on a shaft 107 is a three armed member 10S having one arm 169 bent-over in such a fashion as to overlie the ends of the latch arms 91 and 93 and also another arm 111 bent-over to be in position to register with an abutment 112 formed on the frame 69 when said frame is pivoted in a clockwise direction. A third arm 114 of the three arm member 1118 is urged by a spring 116 into engagement with an adjusting screw 117 threadably mounted within an upturned end 118 of a follower arm 119. Urging the follower arm 119 in a clockwise direction about a stud 121 is an extended tension spring 122. The free end of the arm 119 has rotatably mounted thereon a roller 123 adapted to follow the periphery of a cam 124 fixed to the shaft 31.

In normal operation of the apparatus, the tape 12 is advanced in one step increments by the feed wheel 14 engaging the feed holes formed in the tape. The feed wheel, in turn, is advanced by the pawl 18 and ratchet 17 to successively present transverse rows of permutations 17 to the sets of sensing pins 73 and 67. As each transverse row of permutative apertures 13 is presented to the pins 67 the shaft 31 rotates the cam 29 to present a low portion of this cam to the roller 28 `and as a consequence the cam follower 26 is permitted to pivot in a clockwise direction about the stud shaft 27 to withdraw the adjusting screw 24 from engagement with the extending arm 23 of the bail 21. The bail 21 is thereupon permitted to pivot and obviously thc sensing arms 62 4are allowed to pivot under the influence of the extended tension springs 64. Pivotal movement of the respective sensing arms 62 is prevented whenever a nonperforated portion of the tape is positioned in register with an associated pin 67 of the respective sensing arm 62. Pins 67 which are in register with the perforations formed in the tape are permitted to move upwardly and pass therethrough, thus allowing the associated sensing arm 62 to pivot in a counterclockwise direction. Movement of the arms 62 causes the kassociated contact elements 61 to pivot and close the contacts 56. Closure of any of the contacts 56 conditions circuits which may be traced from ground, through the conductor rod 58, through the respective contact lever 61, through the contacts 56, over the respective leads 54, to the segments 47 to 52, inclusive.

Upon continued rotation of the shaft 31, the brush 59 which is normally positioned on the stop segment 53, successively engages the segment 46 to impress a no current or start impulse over the transmission line 45; then successively passes over the segments 47 to 52 to impress a series of impulses over the transmission line 45 as determined by the conditioned leads 54 connected to the respective segment; and, nally passes `over the stop segment 53 to again impress a current or marking impulse which is indicative of a stop impulse.

Considering now the specific improvement, the rotation of the shaft 31 causes the cam 88 to present a low portion to the cam follower roller 86 at a time subsequent to the operation of the cam 29 thus permitting the operating arm 83 to pivot in a clockwise direction to withdraw the adjusting screw 81 from engagement with the extension 79. The intermediate lever 76 is thereby permitted to pivot under the influence of the extended tension spring 78 if the sensing pins 73 ascertain the presence of six perforations in the tape 12. Obviously if such a situation exists the entire frame 69 will pivot in a clockwise direction because the force of the spring 78 is applied through the intermediate lever 7 6, through the link 74 to the frame 69. Movement of the frame 69 moves the latch arm 91 to position the notch 92 beneath the bent-over portion 97 of the arm 98; therfeore, the latch arm moves upward to engage the bent-over portion 97 within the notch. Movement ofthe frame 69 also positions the abutment 112 in register with the bent-over arm 111 of the three arm member 108. When the cam 124 presents its high portion to the roller 123 to pivot the follower arm 119 about the stud 121, pivotal movement of the follower arm 119 withdraws the adjusting screw 117'from engagement with the arm 114 of the three arm member 108. Recalling that the abutment 112 is now in register with the bentover arm 111, then it becomes apparent that the three arm member 108 cannot pivot about the shaft 107 through the inuence of the extended tension spring 116.

The permutations of apertures presented in register with the sensing pins 67 controls the transmission of a signal indicative of this permutation to the transmission line, however, if the shaft 31 continues to rotate to again present a high portion of the cam 88 to the roller 86, the cam follower 87 moves against the extension 79 to pivot the intermediate lever 76 against the action of its extended tension spring 78. Movement of the intermediate lever 76 is imparted through the link 74 to the frame 69 to restore it to its initial position as shown in the drawing. When the frame 69 is returned to its initial position, the latch 91 now engages within the notch 92 the bent-over portion 97 of the arm 98 and thus moves the arm 98 in a counterlockwise direction. This movement of the arm 98 eifectuates a closure of the contact 101 to complete the obvious shunt circuit for the transmission line 45 which may be traced from ground through the closed contact 101, over the lead 102 to the transmission line 45. The bent-over portion 97 of the arm 98 now overlies the notch 96 and consequently the spring urged latch arm 93 is moved upwardly to engage the bent-over portion 97 within the notch 96 and thus hold the bent-over portion 97 and the arm 98 in a latched position.

It' the next set of apertures 13 to be presented to the sensing pins 73 consist of six perforations then the abutment 112 is again moved into register with the bent-over arm 111 to prevent any release of the latch 93 by the bentover arm 109 because the three arm member 108 is now prevented from movement upon release of the adjusting screw 117 from engagement with the arm 114. If, however, the next set of transverse apertures 13 to be presented to the sensing pins 73 do not have perforations in all six code positions then the frame 69 is prevented from pivotal movement, thus as the shaft 31 rotates to present the high portion of the cam 124 to the roller 123 the arm 119 will pivot to withdraw the adjusting screw 117 from engagement with the arm 114. Release of the arm 114 permits the three arm member to pivot and as a consequence the bent-over arm 109 moves downward to engage each of the latch arms 93 and 91 to pivot them out of engagement with the bent-over portion 97 of the arm 98. The arm 98 is therefore permitted to move in a counterclockwise direction under the influence of its extended spring to open the contact 101 and break the shunt circuit for the signaling line 45.

Considering now the condition of the signaling line when a transverse row of six apertures 13 is successively positioned in alignment with, rst, the sensing pins 73 and subsequently with the sensing pins 67. When the six apertures 13 are positioned in alignment with the sensing pins 73 the transmitter 43 will transmit a signal as determined by the permutative setting of the sensing pins 63. Upon the sensing pins 73 ascertaining the presence of six apertures in the tape, the bent-over portion 97 is positioned within the notch 92 and the subsequent withdrawal of the pins 73 and the frame 69 from the sensing position causes the shunt circuit to be completed. During the next cycle of rotation of the shaft 31, the brush 59 spans the start segment 46 but this action is ineffective to disrupt the signal line 45 to impress a start impulse over the line. The six apertures in the tape now having been advanced to be in register with the sensing pins 67 cause each of the segments 47 to 52 to be conditioned for energization, thus as the brush rotates over these segments, even though the shunt circuit is disrupted, a continuous marking or current condition exists in the signaling line 45 to maintain the receiving magnets 103 in a continually energized state and prevent the tripping of the receiving apparatus located at station 104. The contour of the cam 124 is such that the three arm member 108 which releases the shunt circuit is not actuated until the brush 59 has completed its travel over the start segment 46.

[n summation thereof it may be appreciated that the presence of six apertures in register with the pins 73 causes a shunt circuit to be completed for the period in which the brush 59 is spanning the start segment 46 of the transmitter 43. During the period in Which the six apertures are next positioned in register with the pins 67 the brush 59 spans the start segment 46 and in succession each other segment to apply continuous battery to the transmission line 4S to effectively prevent operation of the receiving equipment located at station 104.

lt is to be understood that the above described arrangement of apparatus and circuits and the construction of elemental parts are simply illustrative of the application of the invention and many other modifications may be made without departing from the spirit and scope of the invention.

What is claimed is:

l. In a telegraph transmitter, a first sensing means for controlling the generation of signals by the' transmitter in accordance with indicia in a control form, a second means for sensing the indicia, and means operated by the second sensing means ascertaining a predetermined indicia in the control form for precluding the generation of a signal by the transmitter.

2. In a telegraph transmitter, means for generating signals, a first sensing means for ascertaining permutations of indicia lin a control record, mean-s controlled by the first sensing means for operating the generating means, a second sensing means for ascertaining permutations in the control record, and means operated by the second sensing means upon the ascertaining of a predetermined permutation of indicia in the control record for rendering the generating means ineffective.

3. In a telegraph transmitting apparatus, a rotary brush type distributor adapted to generate signals, a-iirst means adapted to sense a tape having contiguous sets of permutative apertures, said first sensing means adapted to control the generation of signals by the distributor in accordance with each set of permutative apertures, a second means for sen-sing each set of permutative apertures prior to sensing by the first sensing means, and means operated by the second means sensing a predetermined set of permutative apertures for precluding the vgeneration of a signal by the distributor.

4. A transmitting apparatus comprising a rotating brush type distributor, means for continually rotating the brush to cause a continuous generation of signals, a first means for sensing permutatively apertured tape to control the generation of the signals, a second means for sensingtlie tape, and means operative by the second means sensing a predetermined permutation of apertures Ain the tape for precluding the generation Aof a signal by the rotating brush passing over the distributor.

5. In a communication apparatus, a start-stop distributor, a brush, means for continually rotating the brush over the distributor, a tape sensing apparatus adapted to sense perforations in a permutatively perforated tape and accordingly control the lgeneration of Vsignals by the distributor, an auxiliary tape sensing apparatus adapted to sense the perforations, and means controlled by the auxiliary sensing apparatus upon sensing of a predetermined permutation of perforations for precluding the distributor from'generating a start signal during one revolution of the brush.

6. In a telegraph transmitter, means for controlling the generation of signals by the transmitter in accordance with indicia in a control form, a signaling line connected to the transmitter, means for sensing the indicia, and means for shunting the signalling line upon the sensing means perceiving a predetermined indicia in the control form.

monete 7. In a rotary type telegraph transmitterhaving a commutator connected to a signaling channel, means for controlling the transmitter in accordance with permutations of apertures in a control form, means for sensing the permutations of apertures, and means operated by the sensing means ascertaining a predetermined permutation of apertures in the control form for shunting the commutator with respect to the signaling channel.

8. In a communication apparatus, a rotary type startstop distributor, means for controlling the generation of signals by the distributor in accordance with the permutations of apertures in a tape, a sensing means, means controlled by the distributor for cyclically rendering the sensing means elTect-ive to sense the apertures in the tape, a normally open contact adapted to shunt the distributor, latching means for holding the contact closed, and means operated by the sensing means ascertaining the presence of a predetermined permutation of apertures in the tape for rendering the latching means effective to close and hold the contact closed.'

9. In a telegraph transmitter, means for controlling the generation of signals by the transmitter in accordance with permutations of apertures in a control form, means for precluding the generation of signals by the transmitter, latching means for operating and holding the precluding means, and means controlled by t'he transmitter for ysensing each permutation of apertures in the control form, said sensing means adapted to actuate the latching means upon ascertaining a predetermined permutation of apertures in the control form.

10. ln a telegraph transmitter, means for controlling the generation of signal-s by the transmitter in accordance with permutations of apertures in `a control form, means for precluding the generation of signals by the transmitter,

latching means for operating and holding the precluding means, means controlled by the transmitter for sensing each permutation of apertures in the control form, said sensing means adapted to activate the llatching means upon ascertaining a predetermined permutation of apertures in the control. form, and means for releasing the latching means upon the sensing means sensing a permutation of apertures other than the predetermined permutation of apertures.

l1. In a tape controlled telegraph transmitter, means positionable in accordance with coded indicia formed in the tape, means controlled by the positionable means for generating signals according to the indicia in the tape, pre-set sensing means adapted to be cyclically moved into engagement with tape, and means controlled by the preset sensing means ascertaining a predetermined coded indicia in the tape for precluding the functioning of the signal generating means.

12. ln a telegraph transmitter, a rotary brush type distributor adapted to generate signals, a signalling line connected to the distributor, a first means for sensing sets of permutative apertures in a tape, said first sensing means adapted to control the signals generated by the distributor, a second means for sensing each set of permutative apertures prior to 4sensing by the rst sensing means, a shunt circuit having a normally open contact connected to the signalling line, and means operated by the second means sensing a predetermined permutation of apertures for closing the contact to shunt the signaling line.

' 13. In a telegraph transmitter, a rotary brush type distributor adapted to generate signals, a first means for sensing sets of permutative apertures in a tape, said iirst means adapted to control the generation of signals by the 8 distributor in accordance with each set of permutative apertures, a second means for sensing each set of permutative apertures prior to sensing by the iirst means, means for advancing the tape subsequent to each generation of a signal to successively present each successive set of permutative apertures to each sensing means, and means operated by the second means sensing a predetermined permutation in the tape for precluding the generation of a signal when the predetermined permutation is advanced to be sensed by the first means.

14. In a telegraph transmitter, a first sensing means for controlling the generation of signals by the transmitter in accordance with sets of indicia in a control form, a pre-set sensing means, means for cyclically rendering effective said pre-set sensing means to sense each set of indicia in the control form prior to the sensing of each set of indicia by said irst sensing means, a shunt circuit for said transmitter having a normally open contact therein, a movably mounted actuator, a first latch connected to said pre-set sensing means, said latch adapted to move said actuator when said pre-set sensing ascertains the presence of a predetermined set of indicia in said control form, and a second latch for holding said actuator when said set of predetermined indicia is sensed by said rst sensing means.

15. In a telegraph transmitter as defined in claim 14 having means for releasing said second latch during the period in which the rst sensing means is sensing said predetermined set of indicia.

16. In a telegraph transmitter as defined in claim 15 having means for preventing the operation of said releasing means when said pre-set sensing means senses another predetermined set of indicia 'following the first predetermined set.

17. ln a transmitting apparatus, a rotary brush type distributor having a start segment, a first sensing means adapted to sense permutations of apertures in a tape and accordingly control the generation of signals by the distributor, a shaft adapted to be rotated, a plurality of cams mounted on said shaft, a movably mounted frame, a set of pins mounted on said frame and arranged in a predetermined permutative yorder, means controlled by one of said cams for cyclically moving the frame to permit the lpins thereon .to probe the apertures in the tape, a shunt circuit having a normally open Contact, an actuator adapted to close said contact, Ia latch connected to said frame and adapted to engage said actuator when said pins ascertain a permutation of apertures which is the same as the permutative order of pins, said latch adapted to move said actuator to close said contact when the frame is moved to withdraw the pins from the apertures, a latch for holding said actuator during the next cyclic movement of the frame, and means controlled 4by another of said cams for releasing said latches after the rotary brush has passed over the start segment.

18. In a transmitting apparatus as defined in claim 17 having a blocking element on said frame for precluding the operation of said releasing means when the next permutation of apertures sensed by the pins is the same as the permutative order of pins.

References Cited in the tile of this patent UNITED STATES PATENTS 1,863,479 Hoover etal. June 14, 1932 2,296,845 Goetz Sept. 29, 1942 2,477,309 Maxwell July 26, 1949

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