US2352031A - Telegraph transmitter - Google Patents

Telegraph transmitter Download PDF

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Publication number
US2352031A
US2352031A US405985A US40598541A US2352031A US 2352031 A US2352031 A US 2352031A US 405985 A US405985 A US 405985A US 40598541 A US40598541 A US 40598541A US 2352031 A US2352031 A US 2352031A
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Prior art keywords
lever
bail
key
transmitting
contact
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US405985A
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English (en)
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Steiner Otto
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Individual
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Individual
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L21/00—Apparatus or local circuits for mosaic printer telegraph systems
    • H04L21/02—Apparatus or local circuits for mosaic printer telegraph systems at the transmitting end

Definitions

  • FIG.1 57x7 ea 32 5s v I INVENTOR. v 33 02320 Steamer 'FIG..2A,, i
  • This invention relates to printing telegraph apparatus and particularly to keyboard controlled signal transmitting mechanism.
  • the invention pertains to the transmission of facsimile telegraph signals.
  • An object of the invention is to provide a key board controlled facsimile telegraph signal trans mitter in which the finger keys may be operated in overlap relation, any finger key being depressible before the transmission of the signal initiated by the previously depressed finger key has been completed.
  • Another object of the invention is to provide a keyboard controlled facsimile telegraph signal transmitter in which each finger key directly controlls a selectable signal transmitting element individual thereto.
  • keyboard transmitter devices In the operation of keyboard devices, it is desirable to aiford the operator as much freedom with regard to the timingof successive finger key operations as possible. This enables operators whose normal speed of operation may vary widely or whose timing may be irregular to operate the keyboard devices without special training or practice.
  • a keyboard transmitter device When a keyboard transmitter device is so arranged and timed that a key lever may not be depressed until the transmission of the signal represented by a previously depressed key lever has been completed or substantially completed an operator may be obliged to adopt a regular or rhythmic touch considerably at variance with that operators normal key lever operating technique and such compulsion may be a source of annoyance to the operator and possibly a source of errors in keyboard manipulation. This is particularly true if the system is designed to operate at a relatively low signaling frequency.
  • the obligation to employ a rhythmic keyboard technique may be minimized by so arranging the keyboard transmitter that as soon as the transmission of a signal combination has been initiated so that it may proceed to conclusion without further control from the keyboard mechanism, a second key lever may be depressed and the selective condition controlled thereby stored so that at the conclusion of transmission of the previously initiated signal combination, the transmission of the signal combination represented by the stored selective condition will follow immediately.
  • the keyboard mechanism is free to be operated during a large percentage of each interval allotted to the transmission of the signal combination and the keyboard transmitter approaches, in freedom of operation, the well known typewriter.
  • each key lever is arranged to rock into operated position a signal transmission controlling lever individual to the key lever.
  • the signal transmission controlling lever becomes latched in operated position and the keyboard mechanism becomes locked so that another key lever may not be immediately depressed.
  • the signal transmission controlling lever withdraws one of two detents from blocking relation to a transmitting contact lever which, however, remains held by a second detent.
  • Each of the transmitting contact levers is normaly held by the two detents in position to hold an associated transmitting contact out of engagement with a transmitting drum.
  • the drum is provided with circumferential rows of conductive' and nonconductive areas in alignment with each of the transmitting contacts.
  • the transmitting drum may be rotated in startstop manner or continuously and the shaft by which it is rotated is provided with a cam the first function of which is to release the second of the two detents holding the transmitting contact lever in normal position.
  • the transmitting contact lever Upon release of the second detent, the transmitting contact lever permits the transmitting contact to engage the circumferential alignment of conductive and nonconductive areas with which it is aligned at the proper point on the surfaceof the drum reg-ardless of whether the drum-has just been set in rotation or has been rotating continuously to efiect the transmission of the combination of impulses from beginning to end thereof.
  • the cam Immediately following the .release of the transmitting contact lever by retraction of the second detent, the cam performs its second function which is to unlock the keyboard mechanism. The unlocking of the keyboard mechanism places it in condition for the depression of another key lever and a. key lever may be depressed while the transmission of impulses of the preceding code combination is in progress.
  • Fig. l is an elevational view partly in section showing the keyboard facsimile transmitter according to the present invention
  • Fig. 2 is. an elevational view partly in section showing details of the keyboard locking mechanism
  • Fig. 2a is an enlarged detail of a portion of thestructure shown in Fig. 2, certain of the partsbeing broken away to show the norm-a1 position of locking bail pins in slots of a bail operating link;
  • FIG. 3 is an elevational view partly in section showing the relation of certain elements when a key lever is depressed.
  • Fig. 4 is a fragmentary perspective view supplementin the showing of the locking mechanism in Fig. 2.
  • FIG. 1 the reference numeral designates the supporting frame of the keyboard transmitter according to the invention.
  • 2 extending across frame II from one side of the keyboard transmitter to the other, and appearing at the right of Fig. 1, pivotally supports a plurality of key levers
  • Leaf springs I5 secured to the frame ll of keyboard transmitter engage the lower edges of the key levers l3 and urge the key levers to their uppermost positions. is provided at its foremost end with a finger key l4.
  • a cylindrical rod l6 which receives the bifurcated upper ends of vertically disposed slides or push bars I1.
  • slides or push bars I! there are key levers l3 and eachslide l1 extends downwardly past its associated key lever H3 in close proximity thereto.
  • Each slide I1 is provided with a forwardly extending lug or projection l8 and a laterally extending projection I9 of the key lever overlies the lug l8.
  • is distended obliquely between each slide I! and a frame member 20 and urges the slides upwardly and in clockwise direction as viewed in Fig. 1 so that their bifurcated portions rest a ainst the bar l6 and their lower ends rest against a stationary bar 22 se-- cu ed t the frame H of the transmitter.
  • each of the signal transmission controlling levers 23 is provided with a projection or lug 24 which underlies a rearwardly extending lug or projection 26 of the associated slide H.
  • the signal transmission controlling levers 23 are urged in clockwise direction to bring their, projections 24 into abutting relation with the projections 23 of slides I! by leaf springs 21 secured to the frame ll of the transmitter in the same manner as springs l5.
  • the slides are provided with notches, one on Each ofthe key levers I3 ends by arms 33 pivoted at 34.
  • the alignment of notches 28 is adapted to receive a lock bail 32 extending across the entire. bank of slides l1 and supported at its opposite Similarly, the alignment of notches 3
  • Lock bail 36 is provided with a blade 39 extending obliquely upwardly toward the rear of the transmitter from the rearmost edge of the lock bail 36 and the blade 39 normally abuts the rearmost edge (right-hand edge as viewed in Figs.
  • which is in the form of a pivoted vane extending across the bank of slides l1 and having its foremost edge, which is the left-hand edge as viewed in Figs. 1 and 3, disposed in the alignment of notches 29.
  • is shown in Fig. 1 in its normal position and in Fig. 3 in its operated position and when it is in the normal position it holds the lock bail 36 clear of the rear edges of the slides or push bars
  • At least one of the arms 33 which supports the lock bail 32 is provided with a laterally extending pin 42 (Figs. 2 and 4) and the adjacent one of the arms 31 which supports lock bail 36 is provided with a laterally extending pin 43.
  • a tension spring 44 interconnects the pins 42 and 43 so that look bail 32 is urged to the right as viewed in Figs. 1 and 2 seeking to enter the alignment of notches 28 and the lock bail 36 is urged to the left seeking to enter the alignment of notches 3
  • the pins 42 and 43 carried by the lock bail supporting arms 33 and 31 respectively, are disposed in elongated slots 46 and 4! respectively in a link 48.
  • Link 48 extends to the rear of the transmitter (to the right as viewed in Figs. 1 and 2) and is operable by a cam operated lever, as will. presently appear, which normally holds link, 48 in its foremost position (left-hand position as viewed in Figs. 1 and 2).
  • Spring 44 urges pin 42 toward the right-hand end of slot 46 and pin 43 toward the left-hand end of slot 41.
  • Pin 42 does in fact engage the right-hand end of slot 46 when link 48 is in its normal position and in this position the link 48 holds lock bail supporting arm 33 in position to hold lock bail 32 clear of the alignment of notches 28.
  • Pin 43 does not normally engage the left-hand end of slot 41 but is held toward the right of slot 41, as shown in Fig. 2a, by universal bail 4
  • lock bail 36 is no longer blocked out of the notches 3
  • the apparatus may even be arranged so that when lever 23 is rocked to extreme counterclockwise position its arm 52 will .cam lock bail 36 slightly to the right as-viewed in Fig. 1, bail 36 immediately returning to engagement with the edge of the depressed slide I! when arm 5?. of the operated lever 23 has been drawn clear of flange 5
  • will block the return path of arm- 52 of lever 23 and when lock bail 36 has entered the alignment of notches 3
  • Each of the signal transmission controlling levers E3 ' is also provided with an upstanding arm 53 the upper end of which isnormally presented to the left and in blocking relation to oneof two projections at the lower end of a transmitting contactlever 54 of'which there is one associated with each of the signal transmission controlling levers 23.
  • the transmitting contact levers 54 are pivoted at 56 and each lever 54 carries at its upper end an insulating cap 5'. which engages an individual. transmitt ng contact spring 58.
  • the transmitting drum 56 may be similar to that shown in Patent 2.046.328 granted July 7, 1936, to Edward E. Kleinschmidt et al.
  • Drum 59 may be rotatable continuously or may be operable upon the start-stop principle, being released for one revolution upon each operation a of a key lever l3 in well-known manner.
  • each of the transmitting contact control'levers 54 has two latching or detent projections" at its lower end, one of which is normally blocked by the projection 53 of the'associated signal transmission control lever 23.
  • the other of the detent projections is normally engaged and blocked by a bail 6
  • Shaft 64 to which transmitting drum 59 is fixed, has secured thereto a cam 66.
  • the periphery of cam 66 is engaged by follower rollers 61 and 68 carried by cam follower levers 69 and 1
  • pivotallyengages the rearmost end (right-hand end asviewed in Figs.
  • link 48 which engages, by means of slots 46 and 41, the pins 42 and 43 respectively, carried by the lock bail arms 33 and 31, respectively, all as previously described.
  • link 48 is provided with an elongated slot 13 through which extends a pin 14 carried by a link 16 which is pivotally connected to the cam follower lever 69.
  • has a sloping surface disposed in the path of pin l4, so that when link 16 is moved rightwardly as viewed in Fig. 1 pin 14 will engage the sloping surface of arm 62 and will cam the arm in counterclockwise direction, thus withdrawing bail 6
  • Upon the return of link 16 and its pin 14 bail 6
  • Link 16 supports at itsforemost end (left-hand end as viewed in Fig.
  • follower lever 69 is permitted to return to its normal or extreme counterclockwise position. Such return is accompanied by movement of restoring bail shall not move into blocking, relation to the transmitting contact levers 54 until the restoring bail H has returned toward its normal position a sumcient distance to permit the selected one of the transmitting contact levers 54 to escape from the bail 5
  • transmitting contact levers 54 or a selected one of them should not be enough to permit the associated transmitting'contact 58 to come into vided in the peripheral portions which a transengagement with drum 59, unless the drum is provided in the peripheral portions which a transmitting contact 58 would engage at the time with non-signal transmitting areas, so that no false signals will be applied to the communication channel.
  • cam follower rollers 51 and G8 are very close together and since both are operated by cam 96 the operation of cam follower lever H will lag only slightly behind that of cam follower lever 69.
  • the cam follower lever H moves its link 48 rightwardly as viewed in Fig. l to withdraw lock bail 35 clear of the alignment of notches 3
  • cam follower lever ll has been rocked to extreme clockwiseposition by the apex of cam 36, lock bail 38 has been retracted into position where its obliquely extending blade 39 is blocked by universal bail 4
  • the reason for locking the slides I! by means of the lock bail 32 at the time that lock bail 36 is withdrawn is that the operation of cam follower lever 1
  • the drum 59 If the transmitting drum 59 is operable upon the start-stop principle and another key lever has been depressed, the drum will not be arrested at the completion of a cycle but will continue to rotate for execution of the next cycle and the transmission of the signal combination representing the key lever depressed. If another key lever has not been depressed, the drum 59 will be arrested at the completion of the transmission of the signal combination for the last key lever depressed. If on the other hand the drum 59 rotates continuously, the cam 66 will again operate the cam follower lever 69 whether or not a key lever has been depressed. As the cam follower lever 69 is rocked to extreme clockwise position, bail 6
  • cam follower lever 69 if no key lever has been depressed will be merely to disengage bail 6
  • will be to lock momentarily the slides I! by lock bail 32, since lock bail 36 is held clear of slides H by universal bail ll.
  • cam follower lever 69 operates bails 6
  • a movable signal sending mechanism having keys biased to inoperative position, means for locking said keyboard said means being biased to locking position, two separate means for holding said locking means in inoperative position, means actuated by depressing a key for rendering one of said separate means operative and the other inoperative and means operable on release of said key for rendering said one means inoperative, means operated by depressing said key to initiate the movement of said signal sending mechanism and means responsive to the initial movement of said mechanism to unlock the keyboard.
  • a movable signal sending mechanism having keys biased to inoperative position, means for locking said keyboard said means being biased to looking position, two separate means for holding said locking means in inoperative position, means actuated by depressing a key for rendering one of said separate means operative and the other inoperative and means operable on release of said key for rendering said one means inoperative, means operated by depressing said key to initiate the movement of said signal sending mechanism, means responsive to the initial movement of said lever for normally and primarily blocking its mechanism to unlock the keyboard, means for storing signal originating conditions, and means actuated by a second key depressing for controlling the storing means.
  • a telegraph transmitter in a telegraph transmitter, a plurality of key levers, a slidein engag'ement,with each key lever, a storage'lever operable'by each slide, abail for locking all of the slides following operation of one, a bail for, holding the operatedstorage lever in operated position, a transmitting contact lever corresponding to each storage lever, a projection carried by each storage lever for normally and primarily blocking its contact lever, a bail for blocking secondarily any transmitting contact lever which has beenunblocked by its storage lever, a transmitting contact controlled by each contact lever, a driven transmitting drum to be engaged by said contacts individually, a cam driven with said drum, a lever controlled by said cam for actuating said blocking bail to release a primarily released contact lever and for subsequently restoring said contact lever to primarily and'secondarily blocked condition, and a lever also controlled by said cam for retracting said locklng bail to unlock said slides.
  • a telegraph transmitter a plurality of key levers, an escapable member in engagement with and operable by each key lever, a storage lever operable by each escapable member before it escapes from the key lever, a bail for looking all of the escapable members following escapement of the operated one, a bail for holding the operated storage lever in operated position, a transmitting contact lever corresponding to each storage lever, a projection carried by each storage contact lever, a bail for blocking secondarily any transmitting contact lever which has been unblocked by its storage lever, a transmitting contact controlled by each contact lever, a driven transmitting drum to be engaged by said contacts individually, a cam driven with said drum, a lever controlled by said cam for actuating said blocking bail to release a primarily released contact lever and for subsequently restoring said contact lever to primarily and secondarily blocked condition, and a lever also controlled by said cam for retracting said locking bail to unlock said escapable members.
  • a telegraph transmitter a plurality of key levers, an escapable member associated with and operable by each key lever, a storage element operable by each escapable member before it escapes from the key lever, a bail for locking all of the escapable members following escapement of the operated one, a bail for holding the operated storage element in operated position, a transmitting contact lever corresponding to each storage element, said lever being formed with two projections, said storage element being adapted to engage one ofsaid projections for normally and primarily blocking its contact lever, a bail for engaging said other projection for blocking secondarily any transmitting contact lever which has been unblocked by its storage element, a transmitting drum to be engaged by said contacts individually, a cam driven with said drum, a levercontrolled by said cam for actuating said blocking bail to release a primarily released contact lever and forsubsequently restoring 'said' contact lever to primarily and secondarily blocked condition, and a lever also controlled by said cam for retracting said locking bail to unlock said es
  • a telegraph transmitter a plurality of key levers, an escapable member associated with and operable by each key lever, a storage element operable by each escapable member before it escapes from the key lever, 'a bail for locking all of the escapable members following escapement of the operated one, a bail associated with said locking bail for holding the operated storage element in operated position, a transmitting contact lever corresponding to each storage element, each transmitting contact lever having two projections, means associated with each storage element to engage one of the projections for normally and primarily blocking its contact lever, a bail engaging the other projection for blocking secondarily any transmitting contact lever which has been unblocked by its storage element, a transmitting contact controlled by each contact lever, a driven transmitting drum for'completing a communication circuit through said contacts individually, a cam'driven with said drum, a lever controlled by said cam for actuating said blocking bail to release a primarily released contact lever and for subsequently restoring said contact lever to primarily and secondarily blocked condition, and
  • a telegraph transmitter 'a plurality of key levers, an escapable member in engagement with and operable by each key lever, a storage element operable by each escapable member before it escapes from the key lever, means for locking all of the escapable membersfollowing escapement of the operated one, and for holding the operated storage element in operated position, a transmitting contact lever corresponding to each storage element, means associated with each-storage element for normally and primarily blocking its contact lever, a bail for blocking secondarily said contact levers, a transmitting contact controlledby each contact lever, a driven transmitting drum for completing a communication circuit through said contacts individually, a cam driven with said drum, a lever controlled by said cam for actuating said blocking bail to release a primarily released contact lever, and for subsequently restoring said contact lever to primarily and secondarily blocked condition, and a lever also controlled by said cam for retracting said locking means to unlock said escapable member.
  • a telegraph transmitter a plurality of key levers, a storage element operable under the control of each key lever, a bail for locking the key levers and for holding an operated storage element in operated position, a transmitting contact lever corresponding to each storage element, means associated with said storage element for normally and primarily blocking its contact lever, means for blocking secondarily said contact levers, a transmitting contact controlled by each contact lever, a drum having circumferential areas representing character patterns with a pattern individual to each transmitting contact, a cam associated with said drum, means actuated by said cam during the initial signal transmitting movement for withdrawing the second mentioned blocking means to release a primarily released contact lever, and means also actuated by said cam for retracting said locking bail to unlock said key levers and to release said operated storage element.
  • a telegraph transmitter a plurality of key levers, a storage element operable under the control of each key lever, means for locking the key levers and for holding an operated storage element in operated position, a transmitting contact controlling member corresponding to each storage element, means associated with said storage element for normally and primarily blocking its contact controlling member, means for blocking secondarily said contact controlling members, a transmitting contact controlled by each contact controlling member, a drum havingcircumferential areas representing character patterns with a pattern individual to each transmitting contact, a cam associated with said drum, means actuated by said cam during the initial signal transmitting movement for Withdrawing the second mentioned blocking means to release a primarily released contact controlling member, and means also actuated by said cam for retracting said locking means to unlock said key levers and to release said operated storage element.
  • a plurality of selectively operable storage elements means for holding an operated storage element in operated position, a transmitting contact controlling member corresponding to each storage element and normally and primarily blocked thereby, means for blocking secondarily said contact controlling members, a transmitting contact controlled by each contact controlling member, a rotatable member having alignments of areas representing character patterns with a pattern individual to each transmitting contact, a cam associated with said rotatable member, means actuated bysaid cam for widthdrawing the second mentioned blocking means to release a primarily rleased contact controlling member, and means also actuated by said cam for retracting said locking means to release said operated storage element.
  • a plurality of selectively operable storage elements means for holding an operated storage element in operated position, a transmitting contact controlling member corresponding to each storage element and normally and primarily blocked thereby, means for blocking secondarily said contact controlling members, a transmitting contact controlled by each contact controlling member, a rotatable member having patterns with a pattern individual to each transmitting contact, means associated with said rotatable member, forwithdrawing the second mentioned blocking means to release a primarily released contact controlling member, and for retracting said locking means to release said operated storage element.
  • a telegraph transmitter a plurality of key levers, a storage element operable under control of each key lever, a bail for locking the key levers and for holding an operated storage element in operated position, a drum having circumferential areas representing character patterns with a pattern individual to eachstorage element, a transmitting contact and contact'opcrating levers corresponding to each storage element, means biasing said lever to contact making position, means on said storage lever engaging said contact lever for normally and primarily blocking its contact lever, operating meansfor actuating said drum, a second means engaging said contact lever for blocking secondarily the same and means actuated by the individual. movement of said operating means for withdrawing said second mentioned blocking means and retracting said bailtounlock the key levers.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Push-Button Switches (AREA)
US405985A 1939-12-17 1941-08-08 Telegraph transmitter Expired - Lifetime US2352031A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DES139561D DE765982C (de) 1939-12-17 1939-12-17 Telegraphischer Tastensender zur Aussendung von Impulsreihen, die vorzugsweise Buchstabenbildern entsprechen

Publications (1)

Publication Number Publication Date
US2352031A true US2352031A (en) 1944-06-20

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ID=5831193

Family Applications (1)

Application Number Title Priority Date Filing Date
US405985A Expired - Lifetime US2352031A (en) 1939-12-17 1941-08-08 Telegraph transmitter

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US (1) US2352031A (enrdf_load_stackoverflow)
BE (1) BE442791A (enrdf_load_stackoverflow)
CH (1) CH218236A (enrdf_load_stackoverflow)
DE (1) DE765982C (enrdf_load_stackoverflow)
FR (1) FR870167A (enrdf_load_stackoverflow)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2563355A (en) * 1947-04-07 1951-08-07 Donald B Murray Code transmitter
US2623118A (en) * 1948-10-08 1952-12-23 Creed & Co Ltd Keyboard controlled telegraph apparatus
US2712036A (en) * 1952-02-03 1955-06-28 Moser Otto Teletypewriter keyboard

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB423155A (en) * 1933-07-06 1935-01-25 Siemens Ag Improvements in keyboard impulse transmitters for use in teleprinting systems

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2563355A (en) * 1947-04-07 1951-08-07 Donald B Murray Code transmitter
US2623118A (en) * 1948-10-08 1952-12-23 Creed & Co Ltd Keyboard controlled telegraph apparatus
US2712036A (en) * 1952-02-03 1955-06-28 Moser Otto Teletypewriter keyboard

Also Published As

Publication number Publication date
BE442791A (enrdf_load_stackoverflow) 1941-10-31
FR870167A (fr) 1942-03-04
CH218236A (de) 1941-11-30
DE765982C (de) 1954-09-27

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