US2214631A - Automatic responding arrangement for use in telegraphic printers - Google Patents

Description

1Q, 1940. BECClO I 2,214,631

AUTOMATIC RESPONDLN'G ARRANGEMENT FOR USE IN TEIJEGRAPHIC PRINTERS Filed April 23, 1958 2 Sheets-Sheet l AT TQFEN KEY ET FORUSE m TELEGRAPHIC PRINTERS AUTOMATIC RESPONDING ARRAi-IGEME 2 Sheets-Sheet 2 Filed April 25, 1938 N v E N TOR Giuseppe fiecc/o. WW

ATTORNEY.

Patented Sept. 10, 1940 AUTOMATIC RESPONDING ARRANGEMENT FOR USE IN TELEGRAPHIC PRINTERS Giuseppe Beccio, Ivrea, Italy, assignor to the firm Ing. C. Olivetti & C. S. A., Ivrea, Italy Application April 23,, 1938, Serial No. 203,770 In Italy January 10, 1938 v In telegraphic printing installations operating from a central station which may be either a manually or automatically operated station any one of the pieces of apparatus may be connected at will with any other piece of apparatus in a manner similar tothat of a telephone exchange; Furthermore the machine which is responsive to the call may receive the message even Without I, the intercession of an operator since once the machine has been started up in synchronism it operates automatically to "print the message. If however, there is no operator to respond to the call it is .necessary to provide some assurance for the transmitting operator that he has actually obtained a connection with the required station before the message is transmitted. v

To provide forthis exigency automatic responsive devices are provided which as a result of the reception of an appropriate signal sent by the calling machine puts into action mechanism forming part of the called machine which serves to send a numberof signals or letters which form the characteristic call sign of the called machine. The object of the present invention is to provide an automatic responding means whichis of exceptional certainty in operation, and which though very simple is well adapted to sen the call sign with greatrapidity. e

The apparatus is particularly well adapted to operate with telegraphic printers of the kind known as start-stop operating upon the basis of a code involving five impulses which areimpressed upon the double or single current lines.

The invention is illustrated by way of example in the accompanying drawings as applied to a transmitter embodying an interrupter using simple current. In the drawings: H

Fig. 1 is a sectional elevation of the .arrange-. ment,

4 Fig. 2 is a view showing details of the couplin arrangement, v

Fig. 3 is a plan view,

Figs. 4 and 5 are views of the mechanism to which are transmitted the movement of a universal controlling member and by;,which such movements are transmitted to .theassembly,

Figs. 6 to 8'show details of the mechanism for the transmission of movements from the control, v

Fig. 9 illustrates a safety arrangement for the crank-pin which is to engage with a toothe wheel operated by theassembly,

Fig. 10 shows an arrangement of control lever 5 for the code bladescarried by the drum.

with. As these levers are depressed they operate 10 upon inclined teeth, provided upon six parallel and co-related bars, in such a manner as to eifect a longitudinal displacement thereof. Five of these bars 2 are concerned with the impulses to be transmitted, whilst the sixth which is'always 15 moved in the same manner whatever the pressure of'the touch applied thereto may be, serves to operate the coupling which brings the group of transmission cams into movement. These cams I make one complete revolution for each letter or 20 sign transmitted after which they come to rest even though the key should be kept depressed.

Fig. 2 is solely concerned to illustrate the con- I trol of the coupling. The universal bar 3 is moved towards the left (or in the direction of the arrow) as a result of the depression of anyone of the character levers l and serves to rotate a lever 5 through a small angle about a pivot 4.

This lever 5 is pivotally connected at its upper end with a link lithe free end of which is con- 30 nected with a tension spring 8 whichserves to draw it against a further lever l0 pivoted upon ashaft ll.- Upon'theshaft II is rigidly mounted alever I 2; the free end of which serves as an abutment for astop tooth 13 on the coupling 30 I4 mounted upon a shaft [6. The tension spring 8 is connected with the lever ill in such a manner that it tends to rotate the system of levers in a clock-wise direction thus maintaining the lever l2 in engagement with the tooth I3 on the 40 coupling. The link 6 is provided with .a tooth l, and this, tooth, when the bar 3 is displaced as the result of the depression of a key serves to rotate lever I0 together with lever l2 in the opposite direction thus disengaging lever H from 45 the tooth IS on thecoupling l4 and the shaft I6 commences to rotate in the direction of the arrowv in Fig. 2.

In order to prevent the shaft Hi from making more than one complete revolution, should a key 50 be maintained depressed, the shaft l6 carries a cam I! which during the rotation acts upon the link 6 to lower it in such a manner that the tooth I is disengaged from lever l0 and the latterpermitted to return to its position of rest under the pull of spring 8, the lever I2 at the same time moving back into the path of the tooth I3 of the coupling. When the key is freed the bar 3 is returned to its position of rest under the pull of a spring not shown and the link 6 engages afresh with the lever l (Fig. 2).

Upon the shaft I6 is mounted a group of five cams H! with which engage projections 22 upon levers 20 rotatably mounted upon a shaft 2|, these levers being maintained in engagement with the cams under the influence of springs l9.

The cams "are provided with slight depressions into which the projections 22 may enter to produce oscillation of the levers 29. I The depressions of the various cams are angularly spaced from one another in such a manner that the various levers 28 make oscillatory movements in succession to bring their extremities 23 into contact with a frame 24 pivoted upon a shaft 25, this frame carrying one of the contacts of a contact breaker 26 arranged in the transmission line and normally held closed by means of a spring 2?. The spring 21 is overcome by the levers 23 as they make the contact with the frame and thus bring about the opening of the contact breaker and the interruption of the transmission current. The

five code bars 2 are provided in known manner with teeth inclined either to the right or to the left, against which the key levers l engage to bring about displacements of the bars to the right or the left according to the inclination of these teeth, The bars 2 are provided with angular projections 29 upon which are formed teeth 30 of a form suitable for engagement with the end of the lever-20 when a bar is moved to the left. As a consequence of this, the levers 20 which correspond to bars displaced to the left, cannot respond to springs it upon the passage of a depression in the cam, and as a consequence they do not oscillate and do not have an effect upon the circuit breaker. On the other hand levers corresponding to those bars which are displaced to the right, may oscillate and operate the circuit breaker; By virtue of the various combinations which can be obtained of positions of the five bars, it is possible to obtain in known manner combinations which correspond with impulses imposed upon the transmission line. v

Having considered the :manner in which the transmission of impulses is eifected under normal conditions of operation of the machine, we may now consider the automatic responding arrangement. Upon a pivot i rigidly mounted upon the chassis frame of the machine (Fig. 1) are freely mounted five levers 52 each provided with a beak 53 and having a lateral projection upon its free end which contacts with the extension of one of the levers Z8 and the movements of which it each of which is inserted a blade which is fixed follows. Parallel to the cam shaft 96 is mounted a drum 54 having a series of radial notches in in a suitable manner and is of a length sufiicient to extend over the five levers 52, and provided at points opposite to each of these levers withparts shaped in such a manner as to project from the periphery of the drum or tocoincide with this periphery. The gaps and the projecting parts represent the code of a letter, and in consequence each blade corresponds to a letter.

Assuming for the moment that the drum 54 is turning in such a manner that one of the blades has been brought opposite the beaks 53 of the levers 52; after having moved all the code levers to the right, in order that the levers 2!! shall not be acted upon, the group of cams may be caused being rigid with the chassis of the machine.

to make a rotation. When the recess of each cam comes into a position opposite the'projection 22 of the corresponding lever 2%, this lever rises and causes the end of the lever 52 to rise also as a result of its rotation in a clockwise di rection. If, however, a projecting portion of a blade 55 should lie opposite a beak 531 the lever cannot rise and consequently the lever 28 also is held immovable. All the parts move under the urge of a spring l9 if a re-entrant part of a blade 55 is located opposite the beak 53. In this ay the circuit breaker 26 is operated in the usual manner and transmits impulses to the line which correspond to the code determined by the blade and consequently to the required letter. In the rest position drum E l-is provided with a free zone opposite the beaks 53 in such a manner that oscillations of the levers 52 and in consequence the ordinary transmission, are not interfered with.

The mechanical operation of the system may now be considered. Telegraphic printingqreceivers usually employ a universal member which upon the reception of code signals is'caused to oscillate and thereby operate the printing or any other operable part of the mechanism producing for example the combinations of letters and signs, the spacing of the letters or the lines, etc. This operation is effected through the intermediaryof a connecting member-which is selected in accordance with the received code and which is moved into engagement with the said universal operating member. The connecting member selected by. the settled code for determining the operation of the machine consists .of a drawbar. 28 (Fig. 4) which upon arrival of the said code is moved inthe direction of the arrow. The manner in which this drawbar is controlled is not illustrated in the drawings since this'may be carriedout in various ways according to the type of machine employed. The free-end of the draw bar 28 is pivotally mounted upon a link-zfiitself pivotally mounted at 58, thelast mentioned pivot The drawbar 28 is provided with a'tooth-or projection 30' which cooperates with a-- hookon one. extremity of a further drawbar so that the latter is moved by the first.- The other end of the last mentioned drawbar 3i is pivotally'connected with one arm on a cranked lever 34, this cranked lever also being pivoted as shown at 59 upon the chassis of the machine. Engagement of the hooked end of drawbar 3| with the tooth 30, is maintained through the medium of a'vertical link .tzwhich is pivotally connected at its lower end to one of the keyboard levers 33. The operationv of this connection will now be described.

Displacement of the drawbar-23 causes cranked lever 34 to rotate about its pivot, and this movement serves to impart a downward thrust to the extremity 35 of a lever 36 pivoted at 31 upon the chassis of the machine (Fig. 5). During this movement the pull of spring .38 is overcome, the lever turning in a counter-clockwise direction. The movement is transmitted through a link 39 to an arm 4]] whichisfixedly connected with a shaft 4| and as a consequence thisshaft. is caused to rotate but in a clockwise direction. The shaft scribed below, this toothed wheel'being' rigidly connected with shaft 59, Figs. 3, 6 and '7. Upon the arm 42 is carried a pawl consisting of a member 43 pivoted at 44 upon the arm and provided with a tailpiece which contacts with an abutment member 45 under the action of a spring. In the position of rest as shown in Fig. 7 the pawl rests upon a claw 41 carried by the toothed wheelegrd is able in consequence to transmit the small angt lar rotational movement made by the shaft 4| at the instant of arrival of a call signal, to the toothed wheel 48. The pawl cannot, however, prevent advance rotation of the wheel 48 since when the claw 41 is in the position shown in Fig. 6 and rotation of the wheel continues, the re- 'sistance of spring 46 is overcome, the pawl turned so that it is passed as the rotation continues.

The teeth of the wheel 48 are given a suitable form to enable them to enmesh with a crank-pin or stud 49 on an arm carried by the flange 55 mounted upon the cam shaft IS. The arrangement is such that a Maltese cross type of coupling is obtained, so that as a result of each rotation of the shaft IS the wheel 48 is rotated one tooth. One tooth is missing from the periphery of the toothed wheel however, so that when the wheel 48 reaches its rest position (Fig. 7) rotation of shaft l6 has no effect upon it and neither does it have any effect upon the drum of the automatic response device. Upon the shaft 59 carrying the drum, there is also fixed a wheel having upon the periphery thereof teeth shaped as the teeth of a saw 68 (Fig. 8) which correspond with the teeth of the wheel 48, and a roller 6! carried upon a pin on a lever 62 is adapted to engage in these saw teeth. The lever 62 carrying the roller 61 is pivoted at 63 and is biased by a spring 64 which serves to maintain the roller iii in engagement with a space between teeth on the wheel 59, thus serving to hold the shaft 59 against rotation. The. same shaft also carries two cams 65 and 66 (Figs. 1 and 3). The cam 55 is provided with a recess in which when the parts are at rest a lever 51 carried at one end of a shaft 68 engages. At the other end of shaft 68 there is carried a lever 69 which acts upon the stop tooth of the coupling member l4 operating the cam shaft I6. cam shaft to commence its rotation if the lever 61 is lifted by the cam 65. The cam 66 is also provided with a recess in which engages the end of a lever I2 pivoted upon the shaft and carrying a universal frame 1|. Thus, as a result of the rotation of cam 66 the lever is caused to emerge from the recess therein and the universal frame operates to move all the code bars 2 towards the right, and prevents any operation of the levers 20.

Assuming that the apparatus is at rest, a call embodying-the call sign of the machine brings about a rotation of the shaft '4l and this is transmitted through the pawl 43 to the automatic reponse mechanism. The toothed wheel 48 rotates and brings the first tooth into the path of the stud 49. The frame "H moves the bars 2 and renders them inoperative, whilst the lever ,6! becomes disengaged from the recess in the cam 65 and disengages the coupling l4 so that the group of cams commences to rotate until the first of the blades 55 is brought opposite the beaks 53 of the levers 52. Transmission of the call sign now commences since the lever 51 is held raised by the cam, the coupling I4 is open and shaft I6 continues to rotate. For each complete rotation This mechanism serves to cause the.

the stud 49'advance's one tooth around the wheel 48, and since each tooth corresponds to one of the blades 55 the corresponding codes are successively transmitted.

The lever B! can only fall back and enter the recess in cam 55 when the drum 54 has made a complete rotation. As this lever 5'5 falls it actuates the coupling and arrests the rotation of shaft l5 whilst the universal frame H moves tofree the code bars 2. It is necessary to observe that at the instant when movement commences the action of the drawbar 28 ceases and the whole of the system of control for the pawl 45, and also the pawl itself, return to their positions of rest. As a consequence, upon completion of the rotation the projection 47 on the wheel 48 moves past the pawl which thereupon returns to the latching position and the mechanism is now in condition to respond to a further call.

It has already been stated that the apparatus is characterized by great promptitude and rapidity of operation, and in fact the shaft 16 is in continuous rotation so that the transmission is made at the greatest speed of which the machine is capable without any delay between successive letters.

It has been indicated that the drawbar 3| ,(Fig. 4) which isadapted to be moved by the teeth 30 is maintained in the position of engagement by a vertical link 32 pivoted at its lower end upon a lever 33 which carries one of the finger buttons of the keyboard. If this finger button is depressed the drawbar 3! is disengaged from the tooth 39 and is no longer able to respond to the movements of drawbar 28. This arrangement is necessary for the reason that it is the lever 33 which under the control of the operator determines the transmission of the code call sign of the corresponding machine, and consequently since the transmitted electrical impulses act upon each of the two machines the drawbar 28 of the calling machine is also moved, and if it had not been disconnected from the drawbar 3| it also would set the automatic responsive arrangement of the calling machine in operation simultaneously with the making of a call, thus rendering any transmission impossible.

The blades 55 are mounted in such a manner that they may be readily removed and substituted by others for the purpose of changing the call sign of each station.

The arrangement which has so far been described would be subject to the danger that the various parts might be subjected to abnormal stress which would result in their derangement if as a result of an accidental and incorrect operation the toothed wheel 48 which operates the drum carrying the code blades were displaced from its position of rest whilst the machine is in operation and the wheel 59' is moving. In such an event the stud 49 could strike against the tip of a tooth of the wheel 48 and cause a sudden stopping of the machine with disastrous results. The arrangement shown in Fig. 9 is directed to avoiding this risk. In this construction the projection 49 is not fixed directly upon the wheel 58 but is carried by a lever 15 which is pivoted upon the wheel at 16, and this lever is biased by a spring Ti in such a manner as to tend to maintain the lever in the position shown where it lies in contact with the hub of the wheel 5|]. Under normal operative conditions, during which the projection 49 actuates the toothed wheel 48, the tension upon the spring holds the lever stationary and the operation is without risk.

Fig. 10 shows a further arrangement of levers controlled by the code blades carried by the drum M. This arrangement permits the angle between successive blades to be reduced, and this permits an increase in the number of letters or signs which may be embodied in the reply, for a given size of drum. In place of the levers 52 which are described above as being thrust by levers 28 against the code blades, and which are capable of making movements of relatively large extent, there are employed in the alternative construction levers 18 which tend to be drawn against the drum 541 under the urge of a spring F9. The levers are provided with projections having an inclined surface and they tend to en gage the blades with these surfaces. During the rotation of the drum the code blades operate by their projecting portions against these inclined surfaces and the levers it are thus caused to oscillate upon their pivots 79. The levers 18 are arranged normal to the levers 28 and in such a manner that their lower ends 84! when displaced rest upon the teeth iii of levers 2H, and thus prevent any upward movement of the latter. As the result of this arrangement the levers 213 may be latched and unlatched as a result of slight oscillations of the levers 78, this desirable result being enhanced by the shape given to the pointed form of the projection and permitting a very considerable reduction in the angular spacing between the successive code blades.

'What I claim is:

1. In an automatic responding arrangement for use in telegraphic printers having a rotatable drum for signalizing the response and carrying a number of blades for the purpose of reproducing the code corresponding to the letters to be successively transmitted; a toothed wheel for controlling the rotation of said drum, transmission cams having a shaft, and means on said shaft carrying an abutment, said wheel engageable with said abutment upon advancement of said toothed wheel and said drum for a distance corresponding to one tooth during each complete revolution of. said shaft carrying the transmission cams. I

2. Arrangement according to claim 1 including a resilient coupling on said cam shaft, said abutment being carried by said coupling whereby upon engagement of said toothed wheel with said abutment the latter being moved out of engagement with the toothed wheel.v

3. Arrangement according to claim 1 wherein said toothed wheel is provided with a gap between two adjacent teeth which gap is greater than that between any two other adjacent teeth, providing a period of rest for said arrangement, said abutment being in the path of said greater gap whereby said shaft may rotate independent of said toothed wheel.

4. Arrangement according to claim 1 wherein a transmission mechanism is provided for transmitting an angular rotation to said drum as to bring the first tooth of said toothed wheel into the path of said abutment, a universal member, and means adapted to bring said member into action upon reception of the call sign of said arrangement to selectively control movements of said arrangement including said mechanism.

GIUSEPPE BECCIO.

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