US2259681A - Signal transmission device - Google Patents

Description

Oct. 2 1, 1941. v c. J. cLAYETrE 2,259,631

SIGNAL TRANSMISSION DEVICE Filed Feb. 25; 1939 yz 7% /w 5///////%/ l////// Patented Oct. 21, 1941 U N T E D STATE S PAT EN T UFF-IIC E l SIGNAL TaANsMls sIcNfDsvrcE Claude. Jean Ciayette, Paris," France Applieatinfrebruary 23, 19s9 ,-.seria1 No. 258,090

A (clima-L35) 1 4 Claims.

The present invention relates to telegraphic printing systems for arhythmic transmission.

The object ofthe present inventicn'is toprovide a transmitting system in `which the position of each character is defined by means of a relatively small number of signals-the relationship of which with the displacementsof Athe character carrier is simple.

A preferred embodiment ofthe present invention will be hereinafter described, with reference to the accompanying drawing, given merely by Way of example, and in which:

Fig. 1 diagrammatically shows a developed cylindrical surface on which the characters `are arranged in a system ofrectangular coordinates, beingall located on the same sideof the diagonal line at 45 passing through the origin. in order to avoid any ambiguity; Y

Fig. 2 is a diagrammatical View showing, in perspective, a particular embodiment of anapparatus according to the invention.

As the transmission of the signals corresponding to a character in a `given code ise'ffected through means which are alwaysthesame in all telegraphic systems, I will not describe'the emitting means, which are-Well knownto any person skilled in the art.

At the receiving station, a relay- I,\fitted with an armature 2, which receives the linesignals, controls the movement of shaft 3, driven by a motor 4 through the intermediate of a friction clutch 5.

Shaft 3, through the intermediate of escapement 6, turns through an angle corresponding to one-half of arevolution for each movement of thearmature 2 of relay I. Shaft 3carries a caml on which bear the noses 8a and 8b of sliding members Qa and 9b provided, at I their respective ends, with hooked levers' Illa and` 10b.

Under the action of the respectiveY springs IIa or IIb, each of theselevers Illa and IDb, When its end 8a or 8b is released-'by cam 1, engages its other end in the threads `of =a screw-I2 which turns with a continuous movement of rotation.

It Will be readily understood that, if one of thenosesof levers Illa and Ib'dropsiintofone of the threads of l2, sliding member '9a=or y9b1 is moved toward the lefthand side ofthe device, for the Whole of the time of transmission of a signal. Then, atl the-end of the signal, it is released by cam 1 which lwill have turned through an angle corresponding to half a turn, andit is brought back to its-initial position by the corresponding spring I3a orv I3b.

The lower ends of Ia, Ib are thereforemoved distances proportional to the duration of the signals. Y

"For all signals, they will vbemoved at least asfar-as 'abutments IlIa,'I4b. Only for the long signalsfwill they be moved asfaras Athe abutments I5a and I5b. Y

:It will be readily .understood rthat .onlyone ofv the sliding members canbe driven .at atime, the other lbeing then `at rest.

'The shaft I6 of cylinder I'1Whichicarries the printing characters, is driven, through friction clutch I8, by a .shaft I9, Whichisgivena continuousfmovement'through motor 4,'.pinions 20, 2l, and shaft 22 and pinions;23;=and..24.

On Vshaft I6, there .is fixed an escapement wheel 25y which includes a numberVA of teethzequal to the number off angular positionsofthe printf ing cylinder. Shaft It alsoincludes ansquare portion -26 on which is slidable a sleeve 21 :rigid vwith the printing cylinder .I1. The rear part of this sleevecarriesia screwthread adapted'to cooperate V.With vthe pointedI end of a leverl30," andthe middle part carries ya plurality of annular grooves corresponding'to the number of axial positionsof the printing cylinder.

rThe Whole ofsleeve 21 andicylinder I1 Lcan bemoved inthe rearward direction by .aspring 28 Sand `a liever 46. Abutments 14a, aI4b, .aprovided onapiece-.provided with aiprojection 29, andaetua'ted Aby levers Illa, I Bb, respectively; will permit .the escape of one tooth of 'ratchet Wheel25.l

VOpposite screw thread 21, therel is valever 30 thepointed end'. offwhich constitutes 1a ykind of nut element .engaged in said vscrew threads. Duringthe 'rotation of IS, sleeve 21;:andrcylinder I1 are therefore .driven with a helical movement as` long Sas-3S engages v21.

,'At-.thetime of the rst long signal, one of the sliding members 9a or 9b actsl on abutments I-5a, 15b' which carry nose 3|. 'Shaft 32 is driven by1motor4 through pinions 20, 2|,shaft 22, pinions 36 and35, shaft34, and" friction clutch33.

ffSliaft'BZ carries a two-position stopping disc 31, Areleased for half a turn bythe movement of abutments I5a and I5b.

'During the rst half-turn, a cam -38 actsfon the nose of lever 39, so that-the nose of this last mentioned lever is released from the-screw thread 21, and a second nose39 -comes tolengage the correspond-ing groove`A of sleeve 21.

The movement of theprinting cylinder I1 f'for' the following signals will be reduced to a rotary displacement.

The second long signal which indicates the end of the combination and corresponds to the printing, and which acts on abutments I5a, I5b, as above, releases shaft 32 for a second halfrevolution.

During this rotation, a cam acts upon the end of a lever 4I carrying the printing wheel 42 which carries the paper ribbon on which the character is to be marked. Consequently, this character is printed when the cylinder I1 is nally stopped.

Simultaneously, a cam 43, acting on lever I4a, disengages the nose 29 of the escapement 25, the latter engaging on the upper end of lever 44.

The shaft I6 of the printing cylinder I1 can then turn freely until cam releases the nose 29 of pawl 44 on which it rested, thus stopping, through its escapement, shaft I6 in its starting position.

Simultaneously, as shaft 32 has finished its second half-turn, it has moved levers 30 and 39 through cam 38, thus releasing sleeve 21, which is=rigid with the printing cylinder I1, and the latter is moved backward under the Vaction of its spring 28 and lever 46. .Y In'order to maintain the relativeipositions of shafts 32 and I6, the latter, that is to say shaft IB, carries a cam 4.1 which actuates the stopping lever 48, on which the cam 49 of shaft 32 comes tobe stopped.

The operations of inking the paper, moving it forward, and reverting, can be ensured through any suitable conventional means.

I will now describe, by way of example, the printing of a letter transmitted to the receiving device, say, for instance, letter O. l

As shown by Fig. 1, which diagrammatically illustrates the developed surface of cylinder I1, the coordinates of this letter are:

In the direction of the axis of ordinates, 3, since the ordinates of all the letters of the flrst lower rowv (including A, B, C, D, E, F, G) are. I; In the direction of the axis of abscissas, 5, since the abscissa of the first Vvertical column on the left (including only letter A) is .2. ...'Iherefore, thecoordinates of letter O being 5 4in abscissas and 3 .in ordinates, I will rst transmit a series of three signals (corresponding tothe smaller of these two coordinates), and then'a series of two signals (corresponding to the difference between these two coordinates).

The first series of signals will move. cylinder I1 helically (owing to .the engagement of the endv oflever 3Il.in screw thread 21) a distance corresponding to three rows of characters thus bringing opposite printing member 42 the point n preceding the printing character N.

On the other hand, as above explained, the last signal of each series is a long signal, so that the-last signal of this series of three willbe a long signal, which disengages vthe end of lever 30'from screw thread 21 and engages the end ofjnger 39 into one of the annular grooves of the sleeve rigid with cylinder I1, so that now, this cylinder can only turn about itsjaxis, without any axial movement. y

The second series of signals is then transmitted, As above stated, it is of two signals. It Aproduces an angular displacement of cylinder I1 ofk an amplitude corresponding to two columns of characters, andthe character positioned opposite printing member`42 becomes O.

The succession of the operations which produce this result is the following:

Initially, all the parts are in the position shown by Fig. 2 (with the difference that the origin of the coordinates of cylinder I1 is located opposite printing member 42). The first series of signals is transmitted, including two short signals and a long signal.

At the beginning of the rst signal, arm 8a drops onto the portion of smaller diameter of cam 1. Under the effect of its spring I Ia, rod 9a pivots about its axis so that the upper end of I 0a comes to engage the helical grooves of cylinder I2, which is also rotating.

At the same time, arm. 8b (corresponding to the other sliding member 9b) is lifted by cam 1, against the action of its spring IIb, and the end of lever IIJb is withdrawn from the helical groove of cylinder I2. Sliding member 9b is then released, and, under the effect of spring I3b, it is caused to :slide-along its axis toward the right hand side ofthe figure.

D ueto thev engagement of I 0a with I2, member 9a is vcaused to slide toward the left hand side ofthe drawing, and it comes into contact with abutment I4a. 'Ihis releases escapement wheel25 from'projection'29. Then as the movement proceeds, the escapement wheel is again caught automatically by projection'29.

The rotation of shaft IS- that has been thus produced has caused a helical displacement of cylinder I 1 (3Ilbeing engaged in the screw thread groove 21) corresponding to one step, so that the point now located opposite printing member 4 2 is'now point a preceding A.

.--Thef-y second short signal is now transmitted. It produces the same result as just above explained, with the difference that sliding member 9a. is released and pulled back by spring I3a, while,-on theY contrary, sliding member 9b is brought intddriving engagement with cylinder I2 `and caused to strike finger I4b to produce the displacement of projection 29 away from escapement'wheel 25.

Therefore, as a result of this second short signal; cylinder I1 is again vmoved forward with a helical movement of an amplitude corresponding toone step, so that the point now brought oppoiIte printing member 42 is now point h preceding The third, and last, signal of the series is a long signal.

The beginning of the operation is of course unchanged. In otherv words, sliding member 9b 17s released, sliding member 9a is brought into engagement withdriving cylinder I2. The end of thisv sliding member 9a acts on abutment I 4a, andcauses it to lift projection 29 away from .thel escavpement wheel 25 for the time necessary fora further angular displacement of shaft I6. Cylinder I1 lis again advanced helically a distanceI corresponding to one step and the point brought opposite printing member 42 is now point n preceding character N. I

But, as this signal is a long signal, sliding member liaA is movedV toward the left to a greater distanceV and its end'comes to act on nger I5a, rigid-*.withgnose 3I.' A(It should be well understood that, if the number of signals transmitted hadbeen even, say'four instead of three, the sliding memberin action would have Ybeen 8b, adaptedY to jact von finger 15b, rigid with I 5a, andnose -3HI would also have been pivoted.) As agresultofthe lifting of nose 3|, wheel 31 is released, `and itV turns throughY 180, to-

v'getherwith shaft. 32. Ehen, the other projection offwheel 31 fis caught by nose 3I and shaft 32 is stopped in this new position. 'As above explained, owing to this rotation of shaft 32, .a cam 38 has come toact on lever 39 so thattheipointed upper end of said lever is withdrawn from the screw-thread groove of sleeve 21, vwhereas a finger 39, rigid with lever 39, is V.engaged into one ,of the annular grooves of sleeve 21.' From this time on, a rotation of shaft I6 will produce a rotation of cylinder I1 about its` axis, without any axial displacement.

The next series of signals is now'transmitted. As.' above stated, in the Aexamplel chosen, it correspondsto ashort signal and a long signal. .Theshort signal'produces the following results, in a manner analogous to that above fully described.A I

Sliding member 9a is released, and sliding member 9b brought into operative connection s with cylinder I2. Finger IlIb is actuated, producing the disengagement of projection 29 from escapement wheel 25. Shaft I6 is allowed to turn through an angle corresponding to one step. In view of the engagement of finger 39 in the annular groove of sleeve 21, cylinder I1 turns about its axis, without any axial displacement. The letter brought opposite printing member I2 is now N.

The next signal is a long signal. During the first part of this long signal, the above described operations are again repeated, and this finally brings character O opposite printing member 42. as desired.

The second part of this long signal produces, as above, a further displacement of sliding member 9a, which acts on abutment IEa, releases wheel 31 for one half revolution and permits shaft 32 to turn through one half revolution.

The operations resulting from this operation have been fully described above. Briefly stated, they are the following:

Cam. 49 causes the printing member 42 to cooperate with character U, to print this letter;

Cam 43 causes escapement wheel 25 to be temporarily disengaged from projection 29, thus permitting free rotation of shaft I6 for a short time;

Cam 38 has caused arm 39 to be withdrawn from the corresponding groove of sleeve 21.

Spring 28 can thus bring back cylinder I1 into its initial position.

Of course, cylinder I1 can bring characters corresponding not only to letters but also to all kinds of signs.

In the above description, it has been assumed that the coordinates of the different characters to be printed or otherwise recorded are rectangular coordinates. But of course this has no limitative value. Any system of coordinates may be employed according to the present invention.

Likewise, instead of using, for transmission, series of signals the number of which characterizes the transmission, I might, without departing from the principle of the invention, characterize the signals by their lengths. Each letter or other sign transmitted would be characterized by a different length of signal.

When the letters or signs transmitted are characterized by the numbers of signals transmitted, a considerable simplification is obtained as a consequence of the fact that there are only two diierent lengths of signals, to wit short signals and long signals, as above described. The mechanisms to be used are then much simpler.

It isagainponted out that the .system according to the invention ensures a reduction of the length or .number ofsignals to be transmitted since, instead of transmitting two values, corresponding to two coordinates, I transmit only the smaller' of these two values, and the difference between .the smaller and the greater.

Of course the apparatus, instead of printing the message transmitted on a paper band, might print it on pages.4

In a general manner, while I have, in the above description, disclosed what I deem to be practical and efficient embodiments of the present invention, it should Ibe well understood that I do not .Wish to. be limited thereto as there might be changes made in the arrangement, disposition, and form ofthe partswithout departing from the principle of the present invitation `as comprehended within the scope of the appended claims.

What I claim is:

l. The method of telegraphic transmission of coordinates corresponding to signs in accordance to a code, which comprises, transmitting iirst by means of electric signals the smaller of the two coordinates, and producing, at the receiving station a simultaneous increase of both of the two coordinates of a marking means, corresponding to the Value of said smaller coordinate, transmitting by electric signals the difference between the two coordinates in question, and producing, at the receiving station, an increase of the corresponding coordinate proportional to this difference.

2. In a telegraphic transmission system, a receiving device which comprises, in combination, a cylinder having, on its surface a plurality of characters each defined by its coordinates in a rectangular system of coordinates having an axis parallel to the axis of the cylinder and another axis of coordinates perpendicular thereto, said characters being all located on the same side of a line which is the geometrical locus of al1 the points of equal coordinates of said surface, motor means for driving said cylinder, transmission means interposed between said motor means and said cylinder, including guiding means for said cylinder adapted to cause it to move helically with a pitch corresponding to that of said line of the system of coordinates, and other guiding means for said cylinder adapted to cause it to move with a simple rotation about its axis always in the same direction, for bringing the two guide means into and out of action, exclusively of each other, means, operative by a series of signals for moving said cylinder proportionally to the smaller of the two coordinates to be transmitted, With said first mentioned guiding means in action, means, operative by a longer signal forming the end of said series of signals, for bringing the rst mentioned guiding means out of action and the second mentioned guiding means into action, and means operative by a second series of signals, corresponding to the difference between the two coordinates to be transmitted, for moving said cylinder proportionally to said diiierence.

3. In a telegraphic transmission system, a receiving device which comprises, in combination, a cylinder having, on its surface, a plurality of characters each defined by its coordinates in a rectangular system of coordinates having an axis parallel to the axis of the cylinder and another axis of coordinates perpendicular thereto, said characters being all located on the same side of a line which is the locusof all .the pointsV of equal coordinates of said surface,l motor means for driving said cylinder, transmission means interposed between said motor means and'said cylinder, including guiding means for saidcylin- 5 der adapted to cause itto move helically vwith a pitch corresponding to that of said line of the system of coordinates, and other guiding means for said cylinder adapted to cause it to move with a simple rotation about its axis alwaysin l0 short. Asignals for bringing the rst mentioned guiding means out of action and the second mentioned guiding means into action, means, operative byra secondseries of short signals for moving said cylinder proportionally. to the difference between thesetwo coordinates to be transmitted, with saidsecond mentioned guiding means in action, andmeans, operative `by a second long signal forming the end of said second mentioned series of short signals, for restoring the parts to their initial position.

. 4. A device according to claim 3 further including recordy supporting means, the means operative by the second long signal being adapted to effectthe printing operation by the cooperation of said record supporting means with said cylinder.

CLAUDE JEAN CLAYEITE.

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