US1902943A - Keyboard transmitter - Google Patents

Description

March 28; 1933. E. P. BANCROFT 4 1,902,943 I KEYBOARD TRANSMITTER Filed May '1, 1931 2 Sheets-Sheet 1 INVENTOR ERWIN R BANCROFT ATTORNEY I March 28, 1933. E. P; BANCROFT 1,902,

KEYBOARD TRANSMITTER Filed Ma 1, 1931 2 Sheets-Sheet 2 A V -m I I--- h m, i m l'm-mm7 Wfifl Jami:

ATTORNEY Qi: I INVENTOR I 'ERWIN a Bmcaon' Patented 28, I 1933 UNITED STATES PATEN'II OFFICE ERWIN P. BAN OF BROOKLYN,v NEW ZOE K, ASSIGNOR T INTERNATIONAL GOI- MUNICATIONS LABORATORIES, INC., OF NEW YORK, N. Y., A CORPORATION OF NEW YORK KEYBOARD TRANSMITTER My invention relates to improvements in keyboard transmitter mechanism for transmitting code signals, and more especially for use in connection with rinting telegraphs.

In keyboard transmltters it has been customary when a key lever has been depressed to set up a code combination for transmission to lock either the key levers or the code bars, and maintain them in the locked condition until the transmission of the signal has been completed. Under these conditions a second key lever cannot be depressed to set up a succeeding combination until' the combination set up by the first key lever has been transmitted and the mechanism'released.

The result is that very little time is allowed between the unlocking of the mechanism and the time at which transmission of the succeeding character signal should start for the depression of the next key lever and difliculty is experienced by the operators in attaining a speed of operation closely approximating that at which the apparatus is set to operate.

The object of my invention is to eliminate this fault by providing a mechanism for reading off the code combination from the code bars at the beginning of the transmission period and thereafter leaving both the key and code bars free to be positioned in accordance with a new combination to be transmitted. I further provide means whereby the code combination to be transmitted after being read off from the code bars is stored in the mechanism until the signals cocrl'responding thereto have been transmitte Another object of my invention isto provide a starting mechanism such that the depression of a second key lever before the transmission of the signals corresponding to the first key lever depressed has been completed will'condition the same to start the mechanism a second time even though the second ke lever be released before the completion o the first signal period. This allows the second set of signals corresponding to the second key depressed to followthe transmission of the first set of impulses without loss of valuable line time. a

Still anotherobject of my invention is to arrange the code bars operated by the key with the selector bars or other part of transmittingmechanism.

a This provides a keyboard wherein the keys can be depressed rapidl and by a very light touch as friction'is r uced-to a minimum and the spring tensions to be overcome are extremely small being only such as to normally hold the key bars but of engagement with the code bars.

' Other features of m invention will be apparent in the description which follows.

Referring to the drawings Fig. 1 shows the startin mechanism;

Fig. 2 shows the essential features'of the code signalling mechanism;

Fig. 3 is a modific tion in part of Fig. 2.

Re erring to Fig. i

The shaft 22 upon which are mounted the various cams shown in Fig. 2 also carries a 34 pivoted at 36. his dog 32, for operating the clutch, corresponds to sto X of Fi 4 and 10 of United States atent No.

17,725 to F. G. Greed, granted July 8, 1930,

although other'forms of standard clutch mechanism may be used.

The stop arm 34 is operated by the counterclockwise movement of the lever 38 about the pivot'39 under the influence of a link 40 connected to the universal bail 31 on the keyboard. This bail is shown pivoted at points 45.

When the key lever 41 is depressed the projection 47 on the bail engages the inclined surface of the lever 40 at 48, causing the lever to rotate on the pivot 46 and thus causing the olperation of lever 38 and the engagement of t e pawl 49 with roller 35 on arm 34.: This pawl 49 is pivoted to the arm 38 at 50 and is held against the stop 51 by the tension spring 37. v

When the pawl 49 comes into engagement with roller 35 the opposite end of the sto arm 34 is forced out of engagement 22 to rotate. During the clockwise rotation released, thus releasing the universal bail 31, the pawl 49 rotates about pivot 50 and I does not depress roller 35. 5

A latch 44 pivoted at 54 is arranged to engage a projection 56 on stop arm 34 holding the transmission of the first code combina-.

it out of engagement with the stop dog 32 whenever the stop arm is operated by the depression of roller 35. Pin 55 carried.- on the clutch housing 32 is arranged to engage the bevelled surface 55 of latch'44 which causes the latch to unlock or disengage the PIO]0- tion 56 and allow the arm 34 to assume its normal position after the shaft 22 has rotated only a small fraction of a revolution.

The purpose of this latch is to lock the stop arm 34in a position so it will not engage stop dog 32 if the universal bail 31 is operated a second 'time before shaft 22 has completed its first revolution. I

An advanta e of this arrangement when applied to a eyboard transmitter of this type is that, not only is it possible to operate a second key lever before the transmission of the code impulse corresponding to the first key lever has been completed, but further that it is not necessary to hold the second key lever operated until the completion of tion. With such an arrangement it is possible to operate two key levers at an average speed in excess of five times the working speed of the transmitter, or three key levers at an average 'speed of approximately two and one-half times the working speed, or

v four key levers at something over one an one-half times the workin speed. While this advantage is apprecia le for a large number of letters, it is, of course, understood that over a period of time the average speed cannot exceed the normal operating speed of the transmitter. However, this mechanism will allow for a considerable unevenness in 45 the operation of the keyboard and permit at the same time the operator to approach very closely the operating speed at which the transmitter is set to operate.

Referring to Fig. 2, 42 represents one of fivecode bars having notches cut in such a manner that the depression of any .key bar or lever 41 will force them into the desired position in accordance with the code representingthat particular key lever. The code bars are five in number in the arrangement shown, although it should be understood that there will be one such for each element of the code with which the mechanism is desi ed to operate.

' hus, if the letter A-key bar is depressed,

the first'and second code bars may be moved to the right, and the third, fourth and fifth to the left. In front of each code bar is a lever or selector bar 2 all mounted on a pivot rod 3 supported in a cradle 5. In addition to the five code bars there is a sixth or unithe roller 4 carried by the shaft 3 upon which are mounted the levers 2 which engage the code bars 42.-

If one of the code bars is in front ofits corresponding lever 2, the left-hand end of 2 will be prevented from moving, thus forcing the right-hand'end of this lever downward. If, however, the. code bar is not in front of its associated lever 2, the left-hand end will move downward, while the right-hand end will be held in the position shown, by the tension spring 14'.

The shaft 22 carries two other cams 8, which engage rocker arms 18 pivoted at 19.

The two arms 18 support a locking bar or bail 9 arranged to pass over or under the ends of the levers 2 according to the position they have assumed. The operation of the bar 9 by cams 8 is such-that when levers 2 have taken their positions in accordance with the selection represented by the particular key lever depressed, levers 2 will be locked in that position. Thus, those levers 2 in front of which a code bar'42 has been placed will have their extreme right-hand end locked in the downward position, while those in front of which no code bar has been placed will be lockedin the position shown. Cam 8 is so arranged that levers 2 will remain locked until near the end of the revolution of the cam shaft 22 or until the completion of the code signal.

Cam 21 allows cradle 5' to return to normal as soon as levers 2 are locked in their selected positions and thereby freeingall selector bars 2 from contact with' code bars 42.

(lo-acting with these five cams and the five levers 2 are five levers 12 pivoted on the bearmg rod 10. The levers '12 are normally held in the position shown by the extensions on the levers 2 and the surfaces of cams 7 During the revolution of the shaft 22, the lower extremity of the five contact operating levers 12 will tend to move to the left or toward the code bars 42, under the tension of springs 14..

Those levers 12 in front of which a projection of lever 2 is found will be restrained from moving, while those having the exten sion on lever 2 out of their path will be allowed to move. Any of the five levers 12 in operating moves its associated arm 26. These arms are rigidly mounted on a common shaft they will operate their respective arms 26 and move lever 16in a counter-clockwise direction causing the tongue 60 to engage contact 61'. Those levers 12 not permitted to move will allow lever 16 to move in a clockwise direction under influence of "springs 28 causing the tongue 60' to engage contact 62. Since the five levers 12 operate in succession causing tongue 60 to engage contacts 61 and 62 in succession, these contacts will 1 be closed in accordance with the code combination representing the particular key lever depressed. In order that contact 62 may be closed after the signals representing each code combination have been transmitted a sixth lever 23 and a sixth cam 25' are provided. The cam has a detent or flat surface located so'the lever 23 is allowed to rotate clockwise to close contact 62 when the shaft 22 is in its stop position.

- substantially the same as the apparatus shown in Fig. 2, except that inFig. 3 the selector bars 2 control the operation of levers 12 through the medium of levers 7 7.

Corresponding parts of Fig. 3 are given the same reference numbers as in Fig. 2. V The operation of code bars 42 by key levers (not shown in Fig. 3) and the positioning of the selector bars 2 in their selected and nonselected positions is the same as in Fig. 2. When the selector bars 2 move to their selected positions, the locking bail 9 is operated to hold them in that osition. When those bars 2 whose ends 73 ave been forced downward the projection 80 of bail 9 will pass over the surfaces 82 and holdthe m in their downward 'positions.

. ,The selector bars 2 which have not been.

moved downward will be held in their normal positions by the projections 80 of the locking bail 9 moving into the notches 81 of the selector bars 2.

When the selector bars 2 are locked in their determined positions the cradle 5 is allowed to return to normal position thereby freeing the code bars42, which may then be set to other positions.

When the portion 73 of the selector bar 2 moves downward, the lower end 76 oflatch bar 77 pivoted at 78 moves inward under the influence of spring 87 and the upper end moves outward and disengages extensions 90 of lever 12 to allow lever 12 to. be controlled by cam 7 in the same manner as in Fig. 2. Forv those selector bars 2 which have not been operated, the latch 77 is not moved to release the portion 90 to allow lever osing of the contact tongue 60 on con- 1 1. A keyboard transmitter comprisin a plurality of depressible key levers for setting up signal combinations, means for transmitting signals corresponding to the combination set up by the depression of one of said key levers, means under control of the signal transmitting means for rendering another of said key levers depressible for transmitting signals corresponding to combinations set up by its depression and before all the signals corresponding to the first combination have been transmitted.

2. A keyboard transmitter comprisin a plurality of depressible key levers for setting k up signal'combinations, means for transmitting signals corresponding to the combination set up by the depression of one of said key levers, means under control of the signal transmitting means for rendering another ofsaidkey levers depressible for transmitting signals corresponding to the combination set up by its depression and immediately after the setting up of the first signal combination.

3. A keyboard transmitter .for transmitting signals comprising a plurality of keys, means for controllin the starting of the transmission of said signals, means for lockin g said starting means when one of said keys 1 is operated, means for unlocking said start-- ing means after the transmissionof impulses has started so it can again be locked by another key independent of the transmission of said signals.

4. A keyboard transmitter for transmitting signals comprising a plurality of keys, mechanism for controlling the transmission of said signals, means for starting said mechanism when one of said keys is operated, means for locking said starting means, and means for unlocking said starting means after the 'transmission of signals has started, so it may be locked again by a' second key independently of the transmission of said signals started by the operation of the first said key. 5. A keyboard transmitter comprising aplurality of depressible ke levers, a plurality of code bars engageabley said key levers when depressed, selector bars having no mechanical connection with said code bars,

means for causing said code bars to become associated with said selector bars in combinations according to the key lever depressed, and transmitting contact operating means controlled by the selector bars.

6. A keyboard transmitter comprising a plurality of movable selector bars, a 'plu- 'rality of movable code bars entirely disconpluralit ofmovable selector bars, a plurality 0 code barshaving unrestrainedrnovement in two directions, means for moving said code bars in one direction in the'pat-h of said selector bars and in another direction. away from saidselector bars, and transmitting contact operating means controlled by v the selector bars.

8. A device comprising a plurality of code bars and corresponding selector bars mechanically disconnected therefrom, means for selecting. a combination of said codebars, means fortransferring the combination selected to said selector bars, a transmitter contact ogeratinglever controlled byeach selector ar, and means for controlling said operating levers in sequence in accordance with {)he combination transferred to said selector ars.

9. A device comprising a plurality of movable code bars and corresponding movable selector bars mechanically disconnected therefrom, means for positioning said c'ode bars, means controlled by the positioning of said code bars to determine the position of said selector bars transmitting. contact operating means controlled by the selector bars, and. means to lock said selector bars in'their determined positions so said code bars maybe moved to other positions.

10. A- device comprising a plurality of movable code bars and a plurality of movable selector bars, means for positioning'said code bars, means to move said selector bars to positions determined by the positions of.

said code bars, and means to lock said selector bars in their determined positions so said code' bars may be movedto other positions. v

11. A device comprising an operating mechanism, means for controlling the operationof said mechanism, means for operating said controlling means to cause said mechanism tofperform one complete operation, and, means for allowing said controlling means to be again'operated before the mechanism has completed its first operation so both operations will be continuous.

12. device comprising an operating mechanism, means for starting the operation of said mechanism, means for stopping the operation of said mechanism afterit has.per-' 'formed'one complete operation, means for operating said starting means to caum the r' operation of said mechanism, and means. for

vallowing said starting means to be again opelated before the perforinairce of its firftopmeans for. setting up said means including a lock controlled by the ro- Y tary cam member to lock the selector elements in set position and free'the permutation elements for another setting during the transmission of the code combination locked on the selector elements.

14. A keyboard transmitter for transmitting signals made up ofa starting impulse, a plurality of selecting impulses and a stop impulse, comprising a plurality of keys, permutation code mechanism'set by the operation of any of the keys and controlling the combinations of selecting impulses 'to be transmitted, a driving shaft, a driven shaft, :1. single revolution clutch for coupling the shafts, means controlled by and during the rotation of the driven shaft to transmit the starting impulses, t e selecting impulses as determined by the se ting of the code mec anism and the stop impulse, a latch normally holding the clutch disengaged, means responsive to the operation of any key to operate the latch and allow the clutch to engage, means effective upon operation of the latch to lock it in operated position, means'controlled by the driven shaft to release the locking means before transmission of the stop impulse and allow the latch to return to normal position so that it may again be operated-and locked in response to the operation of any of the keys before completion of transmission of the selooting impulses.- I

15. A keyboard transmitter for transmitting signals made u of ,a starting impulse,

a plurality of selecting impulses and a stop (determined by the setting of the c e mechaholding the. clutch disen aged, means respom sive to the operation 0 any key to operate the latch. and allow the clutch to engage,

msm and the stop impulse, a latchnormally I means effective upon operationof the latch lecting impulses represented, by the to lock it in operated position, and means of the selectors. I

controlled by the driven shaft and operating In witness whereof, I hereunto subscribe during the transmission of the starting immy name this th da of April, 1931.

pulse to release the locking means thereb ER N P. BANCROFT;

allowing the latch to return to normal position so that it may a aiu be operated and locked in response to t e operation of any of the keys before completion of the transmission' of the selecting impulses.' p

16. A ke board transmitter comprisin a plurality 0? keys, a plurality of permutation.

asset in different combinations b operation of the various keys, a universa bar invariably operated by the operation of any of 86 the keys, selector bars correspondin in number to the number of permutation ars and pivotally mounted intermediate their ends, a rotary cam member started in rotation by operation of the universal bar and having a section for causing the selector bars to tilt in one direction or the other according to the setting of the permiltation bars, a locking bar positioned under control of the rotary cam member to lock the selector bars in their tilted position, a series of successivelyoperatcd sections on said rotary cam member corresponding respectively to the selector bars,

and transmitter contact means operated 'under control of thesuccessivel v operated sec- 1 tions as determined by the ti ted position of the res ective selector bars.

17. keyboard transmitter comprising a plurality of keys, a set of permutation members variously positioned by the operation of the keys, a pivotally mounted cradle, a set of selectorbars pivoted on said cradle,

' transmitter contacts, and a rotary cam set in operation upon actuation of any key and having a section for invariably rocking the cradle about its pivot thereby to cause the selector bars to assume positions determined b the setting of the permutation members'an having a series of successively operative sections 45 for controlling the operation of the transmitter contacts in accordance with the positioning of the selector bars.

18. A keyboard transmitter comprising a a s plurality of keys,a set of permutation memi i bers variously positioned by the operation of the keys, a pivotally mounted cradle, a set of selectors pivoted on said cradle, a rotary.

cam set in operation upon actuation of any 55 key to rock said cradle about its pivot there- 7 by to cause the selectors to assume set positions determined by the setting of the'permutation members, a locking bar controlled by the rotary cam to lock the selectors in set V a so position, transmitter contacts under control Y '125 of the rotary cam and the selectors, and means to restore the cradle to normal position with the selectors locked in set 'tion thereb to free the permutation mem rs for V as re-posltioning before transmission of the se I 139

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