US2787212A - Solvent operated duplicating machine - Google Patents

Description

April 2, 19579 M. A. DELPLANQUE SOLVENT OPERATED DUPLICATING momma 4 Sheets-Sheet 1 Filed May 21, 1954 IllHlllllYl I Hlll April 2, 1957 M. L- A. DELPLANQUE 2,787,212

SOLVENT OPERATED DUPLICATING MACHINE 4 Sheets-Sheet 2 Filed May 21, 1954 April 2, 1957 ML. A. DELPLANQUE 2,787,212

SOLVENT OPERATED DUPLICATING MACHINE Filed May 21, 1954 4 Sheets-Sheet s April 2, 1957 M. L. A. DELPLANQUE SOLVENT OPERATED DUPLICATI [NG MACHINE 4 Sheets-Sheet 4 Filed May 21, 1954 dsets. Pam O SOLVENT OPERATED DUPLICATING MACHINE Marcel Louis Alexandre Delplanque, Paris, France, assignor to Ormig-Urganisations-Mittel G. in. b. H., Berlin-Tempeihof, Germany, a corporation of Germany Application May 21, 1954, Serial No. 431,523

Claims priority, application France April 7, 1954 8 Claims. (Cl. 101 1325) The present invention relates to a solvent operated duplicating machine more particularly of the type described in the U. S. Patent No. 2,660,112 to the inventor.

It has been found that, using such a duplicating machine, it may be required that only a portion or some portions of a hectographic transfer sheet be reproduced. The transfer sheet, for instance may include firstly a heading comprising the general information to be reproduced upon a series of forms and thus constituting a constant portion and secondly some data or a number of lines some of which are to be reproduced upon a given number of said forms while others are to be reproduced upon another restricted number of forms. Such a selection has to be made, for instance, in connection with invoices, partial delivery bills, work bills, planning and many other applications.

The main object of the present invention is to make it possible to reproduce selected portions of a hectographic transfer sheet by means of a novel selecting device which is particularly applicable to a solvent operated duplicating machine.

Another object of the invention is to provide a duplieating machine of the kind described in which means are provided for readily changing the selected portion or portions of the transfer sheet that is or are to be printed onto the blank sheet.

A further object of the invention is to provide a duplieating machine of the kind described which makes it possible to reproduce on a blank sheet one or several selected lines of a transfer sheet, the location of these lines on the blank sheet being precisely the same as the location of the corresponding lines on the transfer sheet.

Still another object of the invention is to provide a duplicating machine of the kind described which makes it possible to reproduce on a blank sheet one or several selected lines of a transfer sheet, the location of this or these lines on the blank sheet being predetermined at will, regardless of the location of the corresponding lines on the transfer sheet.

According to the main feature of the invention, the blank sheet to be printed is wetted and pressed against the printing or transfer sheet carrying roller only on the portions of said blank sheet that are to receive printed matter.

Other and further objects and advantages of the invention will be apparent to those skilled in the art, from a consideration of the following description of two specific embodiments of the invention, shown by way of example, in the accompanying drawings, in which:

Fig. 1 is a side elevational view of a portion of a duplicating machine according to the invention,

Fig. 2 is a section made substantially along line I l-H of Fig. 1,

Fig. 3 is a fragmentary section on line TIL-I'll of Fig. 2,

Fig. 4 is a fragmentary section on line IV-- IV of Fig. 1,

Fig. 5 is a fragmentary section similar to Fig. 4, but

wherein the individual parts are shown in different positions,

Fig. 6 is a fragmentary front elevational view of a detail as seen in the direction of the arrow 6 in Fig. 1,

Fig. 7 is a side elevational view similar to Fig. l of a modification,

Fig. 8 is a fragmentary section on line VIII-VI II of Fig. 7,

Fig. 9 is a fragmentary section on line IX-IX of Fig. 10,

Figs. 10 and 11 illustrate the relative positions of the rollers and the cores of the solenoids for the driving pressure and the printing pressure in their driving and printing positions respectively, and

Fig. 12 illustrates a detail of a brake for the driving roller.

Referring first to Fig. 1, C is a transfer sheet carrying roller rigid on a shaft 11 adapted to be rotated at a uniform rate in the direction of the arrow f by suitable conventional power means (not shown). The roller C may be engaged by a pressure. roller P carried by a spindle 51 rotatably supported at each end thereof in flanges 52 one of which only is visible in the drawing (see also Fig. 2). The flanges 52 are rigid with an arm 53 which is pivotally supported at one end thereof by a horizontal pivot 54 and which is adapted to rest on a stationary stop 55. The other end of the arm 53 is connected to the plunger core 57 of a solenoid E2 by means of a link-56.

As shown in Figs. 1 and 2, a rubber-like disc D is secured to the shaft 11 which carries the transfer sheet roller and another rubber-like disc D2 is secured to the pressure roller P. The diameters of these rubber-like discs are so dimensioned that when the rollers are in the positions illustrated in the drawing, that is to say they do not engage each other and the arm 53 is resting upon the stop 55, the rubber discs, however, are in mutual engagement so that the shaft 11 of the transfer sheet carrying roller causes the pressure roller also to rotate. When the solenoid E2 is energized, it attracts the core 57 which lifts the pressure roller P and presses it strongly against the transfer sheet carrying roller C while the rubber discs are somewhat distorted or crushed on their peripheral face.

The paper sheet 1 to be printed is laid upon a guiding table 4%; it is then carried away between the two rollers 44 and P. When it comes out from between the two rollers, a guide member 46 flexes it and causes it to be passed between the pressure roller P and the transfor sheet carrying roller C. As the paper sheet moves round together with the pressure roller, the locations of this paper sheet which are to be printed are subject to a wetting operation, as will be seen further on, by means of a wetting device F adapted to be actuated by a wetting solenoid E1.

Secured either to the shaft 11 of the transfer sheet carrying roller or to a shaft rotatably connected to said shaft 11 and revolving at the same rate is a selector carrying drum 15 which is provided near its peripheral portion with a plurality of cylindrical recesses 1 spaced apart preferably uniformly and for instance by a distance which corresponds to the line spacing of the typewriter in which the hectographic transfer sheet adapted to be secured to the roller C was established. In each of said recesses or in a given number thereof only, as will be seen further on, selecting keys 2 are arranged and adapted to be shifted longitudinally within said recesses in order to be able to assume either of two positions, namely an operative position as indicated as at 2 in Fig. 2, or an inoperative or rest position as indicated at 2' in the same figure.

Each key 2 carries two radial fingers 2a and 2b which are accommodated in slots 1a cut out into the peripheral zone of the drum 15 and which open into the cylindrical recesses.

When a key 2 is in its operative position, its finger 2a is, during the rotational movement of the drum l5, able to cooperate with a brush 3 carried by an arm 5 which is pivotably mounted on a pin 6 and which is urged to turn clockwise under the bias of a coil spring 7 wound around the pin 6. The length of the brush 3 is substantially equal to the arcuate distance between the two fingers 2a of two successive selecting keys. The brush 3 carries a finger 32 adapted to press a movable contact 34 against a stationary contact 36 when the brush is lifted.

In a similar manner, the fingers 2b of the keys 2 are adapted to cooperate with a brush 4 carried by a lever 5a which is also pivoted on the pin 6. The brush 4 carries a finger 38 adapted to press a movable contact 40 against a stationary contact 42.

The fingers 2a control the wetting device F and to this aim one terminal of a source of electric power S is directly connected to one end of the winding of the solenoid E1, the other end thereof being connected to the other'terminal of the source S through the two contact 34 and 36.

The fingers 2b control the device which presses the paper sheet to be printed against the transfer sheet and to this aim one terminal of the source S is similarly connected to one end of the winding of the solenoid E2, the other end thereof being connected to the other terminal of the source S through the two contacts 40 and 42.

It will be appreciated that it is, of course, impossible to wet the paper sheet on the location situated at the point Where the pressure is applied against the transfer sheet, i. e. on the generatrix of contact between the transfer sheet carrying roller and the pressure roller. Therefore, this paper sheet should be wetted somewhat ahead of this contact generatrix and be pressed against the transfer sheet at the moment the wetted portion is in engagement with the transfer sheet. This is the reason why the brush 3 which controls the wetting operation is located somewhat ahead of the brush 4 which controls the application of the pressure.

The desired selecting keys may be pushed-in individually in order to be brought into their operative position as hereinabove explained.

The keys may be brought back into their inoperative positions also individually by hand, but it is more convenient to provide a common restoring device such as the device which will now be described.

Slidably mounted on the shaft 11 of the transfer sheet carrying roller is the hub 22 of a restoring disc 21 (see also Fig. 3) the diameter of which is substantially equal to that of the selector drum 15, said disc 21 being adapted to engage the inner ends of the selecting keys 2. The restoring disc 21 is urged away from the selector drum 15 by a coil spring 24. An operating rod 26 is axially slidably mounted in the shaft 11 which is formed with a slot 28 to accommodate a pin 30 driven through the operating rod 26 and the hub 22 of the restoring disc 21. It will be readily understood that when the operating rod is pulled toward the left (looking at Fig. 2), the restoring disc 21 is carried toward the left against the action of the spring 24 and all the selecting keys that protrude inwardly are carried by the disc 21 from their operative to their inoperative position.

In order to reproduce the heading on the paper sheet, that is to say the constant portion without it being necessary for each new selection to reset into their operative positions the keys corresponding to this constant portion, suitable segments may be removably mounted on the drum 15. Segments of this type may be seen in Figs. 1 and 6 as indicated at 9 and 10, and secured as by means of small countersunk screws 61 screwed into dummy keys arranged in the same recesses 1 as the slidable selecting keys. These segments are equal in height to the fingers 2a and 2b of the selecting keys and operate in the same manner as these fingers. Any suitable number of such segments may be mounted end to end according to the size of the heading or constant portion to be printed. If desired, segments of different lengths could also be provided.

The operation of the selecting device for a duplicating machine above described is as follows:

Segments 9, 10 which correspond to the height of the heading to be printed on each paper sheet are permanently mounted on the drum 15. Should not the selecting keys be all in their inoperative position, the rod 26 is pulled in order to bring them into such position and then the various keys corresponding to the lines of the transfer sheet to be reproduced pushed-in. Assuming the transfer sheet comprises for instance, besides the heading, 25 lines and that it is desired to reproduce the lines numbers 3, 7 and 15, it merely suffices to press upon the selecting keys which correspond to these three lines.

The transfer sheet carrying roller C may now be set into rotary motion while a paper sheet I is introduced between the rollers 44 and P (Fig. 1). Right at the start, the segments 9, 10 are located near the brush 3 so that, as soon as the sheet has passed the wetting device F, the latter is applied against the sheet by the solenoid E1 under the effect of the two contacts 34, 36 coming into mutual engagement (see Fig. 2). Then, at the moment the wetted portion of the paper sheet reaches under the transfer sheet, the solenoid Ez gets energized due to the closing of the contacts 40, 42 (see Fig. 5). The wetting device is kept applied upon the sheet during a time which corresponds to the height of the heading, that is to say to the curvilinear length of the segments 9, 10 and the pressure is kept applied precisely as long as said wetted portion passes under the transfer sheet. The solenoids are then deenergized due to the contacts coming apart, the blank sheet, however, further progresses as the transfer sheet rotates by virtue of the connection ensured by the rubber discs D1, D2. Every time a pushed-in key passes under the electric contacts, the wetting device is activated and the pressure is applied so that the selected line is printed onto the blank sheet at the precise location on said sheet which corresponds to the location where said line is placed on the transfer sheet.

It is readily understood that the keys that are not selected have no action upon the mechanisms since their fingers 2a, 2b are positioned in a path outside the brushes 3 and 4 (see Fig. 4).

If it is desired that all the lines in the transfer sheet be printed upon the blank sheet, this may be achieved by pushing-in all the keys, or permanently energizing the pressing and wetting solenoids, taking care, however, that the wetting device is not applied upon the presser roller at the moment the blank is introduced into the machine, otherwise such introduction would be impossible. This may be achieved, for instance by designing the machine so that the cam which controls the wetting operation for the heading acts upon the solenoid E1 through a time delayed device which allows the current to be circulated during an interval of time which corresponds to the time required for the transfer sheet carrying roller to achieve one complete revolution.

This selecting device may be used for instance in the preparation of invoices and fractionated delivery bills.

A modification will now be described which allows not only the printing of lines selected as desired said printing taking place on the blank at locations corresponding to the locations of said lines on the transfer sheet, in the same manner as when using the embodiment above described, but also the printing of one or several lines at a given location on the blank whatever may be the location of these lines on the transfer sheet. This feature is quite valuable for establishing work-bills for instance in the heading of which will always appear all the data pertaining to a given workpiece, whereas one (or several) line relating to one (or several) machining operation to be 7 guide cylinder 44.

carried out on the workpiece will have to be printed below said heading. On some bills a turning operation will appear for instance, whereas on others it will be a milling or a drilling operation.

This modification will now be described with reference to Fig. 7 and the following ones. Most of the members already described with reference to Fig. 1 are also illustrated in Fig. 7 and like members are indicated by like reference numerals. Therefore, it is sufficient to describe only what is ditferent in the modification as compared to the previous embodiment.

First, in the device illustrated in Pig. 1, when the lever 53 rests upon the stop 55, the two rubber discs D1 and D2 are in mutual engagement whereas in the modification of Fig. 7, said two discs are some distance apart in order to eliminate any driving connection in this position. When the pressure controlling solenoid E2 is energized (see also Fig. 11) as in the case of Fig; l, the two rubber discs D1 and D2 flatten sufficiently one against the other to make it possible for the pressure roller P to engage the transfer sheet carrying roller C.

Now, provision has been made for a third solenoid Es which will be called hereinafter driving solenoid the core 63 of which is connected to the lever 53 through a link 64 provided with an elongated eye 65 traversed by a pin 66 rigid with the lever 53. The arrangement is such that when the solenoid E3 is energized, it lifts the lever 53 (Fig. by such an amount that both rubber discs D1 and D2 are in mutual engagement under a pressure which is sufficient for driving the pressure roller P as well as the blank sheet introduced between this cylinder and the it will be noted that from this position on (Fig. 10), the pressure controlling solenoid E2 is not hindered in its operation since the pin 66 on the arm 53 is able to rise in the elongated eye 65' of the link 64 now stationary, as indicated in Fig. ii.

The driving solenoid E3 is energized from the source S through a circuit including a stationary contact 71 and a movable contact '72 adapted to be actuated by an extension of the lever of the wetting device F when the latter is in operation. I

73 denotes a segment for controlling the wetter F and "7d a segment for control-ling the pressure solenoid E2.

The object of the above described arrangement is the following: Apart from the printing of the heading which takes place in the same manner as in the embodiment of Fig. 1, it is desired to let the transfer sheet rotate Without the blank progressing, until the line which is required to be printed appears in register with the blank; it is at this very moment that the wetting action is achieved, as well as the rotation of the blank by a length of one line spacing and the application of the pressure upon the zone related to this line.

The operation is as follows:

Assuming it is desierd to print below the heading, for instance the seventh line of the transfer sheet, the selecting key which corresponds to this seventh line is depressed. The machine is set in motion and the heading is printed as previously. The assembly of the movable rollers then falls down for the solenoids are no longer energized, the transfer sheet, however, further rotates, whereas the blank keeps stationary on the pressure roller P which is not rotatively driven. As the seventh line selecting key actuates the contact 34, the wetting device it engages the blank under the effect of the solenoid E1 being energized, it wets the location of the line that follows the heading, and simultaneously closes the contacts '71--72, thus ensuring the energization of the solenoid Es which drives the blank through the temporary connection achieved by the rubber discs D1 and D2 now in rollengagement, The ringer on the selecting key frees then the brush 3 thus releasing the wetter F and the driving roller; prior to this event, however, the finger 2b of the same finger had lifted the brush 4 and, therefore, caused the pressure solenoid E2 to be energized and this seventh line of the transfer sheet to be printed below the heading on the paper sheet I.

It is appreciated that it is possible to print below the heading any desired line of the transfer sheet and that for this purpose it merely sufiices to depress the correspondin g selecting key.

if desired, it is possible to thus print a plurality among any lines of the transfer sheet, one after another on the blank, even though such lines are not successive adjacent lines on the transfer sheet, since there is the possibiiity for the transfer sheet to be continuously rotated while the blank may be kept stationary between two line prints.

In order that the momentum of the parts in motion be unable to interfere with the progression of the blank by one line spacing only, there is provided an automatic brake intended to absorb the kinetic energy stored within the pressure roller I. To this aim, secured to the spindle 51 of this roller is a brake roller 77 (see Fig. 12), preferably knurled, which comes and rests upon a stationary rubber block 78 as soon as the movable assembly of the rollers falls down.

It will be noted that after the last line has been printed, the pressure roller P sinks and that if no particular step were taken, the printed sheet would stay within the machine. This is the reason why provision has been made for a so-called ejection cam (segment 79 in Fig. 8) which, new the completion of the rotational movement of the transfer sheet carrying roller, ensures the energization of the solenoid E2 for causing the pressure roller to rotate and hence the printed sheet to be thrown out of the machine.

Using the device which has just been described with reference to Fig. 7, it is also possible, providing a very light modification is achieved, to carry out, as with the device of Fig. 1, the printing of selected lines of the transfer sheet onto locations on the blank sheet which precisely correspond to the location of these lines on the transfer sheet. For this purpose, the blank sheet should therefore be permanently driven simultaneously with the transfer sheet and, therefore, the driving solenoid E3 should be permanently energized, for instance by means of an additional switch 81 (Fig. 7) which short-circuits the contacts 71-72. The operation is then the same as for the device described with reference to Fig. l. v

I Moreover, if it is desired to print upon the blank all the lines of the transfer sheet, this may be achieved in depressing all the selecting keys. However, the same result may be obtained by permanently energizing the pressure solenoid E2, for instance by means of an additional switch 82 which short-circuits the contacts 4042. Nevertheless, the wetting device should not be left permanently in engagement with the pressure cylinder P because this would prevent inserting the blank sheet under the transfer sheet. It is therefore necessary to release the wetter for a short time after each complete revolution of the transfer sheet for enabling the blank sheet to be inserted. In order to achieve this result, use may be made for instance of the heading wetting cam 73 and the solenoid E1 may be energized through a time-delayed device 83 (Fig. 7) which keeps the electric current flowing during a time nearly equal to the time required for the transfer sheet carrying roller to achieve one complete revolution.

For a more comprehensive description, an example is now given of the printing of a series of invoices.

Assuming an order includes twelve articles and necessitates three deliveries, the device will make it possible to reproduce the constant (general information) comprising four lines to be printed by providing four segments 9 mounted in the first four recesses and ensuring a continuous normal operation of the duplicating machine according to the corresponding circular arc.

Assuming the first delivery includes three articles on the lines numbered 6, 9 and 10, respectively, the keys 7 inserted in the recesses 6, 9 and should be depressed. The transfer sheet carrying roller is continuously rotated and will carry the blank sheet 1, without soiling it, by virtue of the disc train D1, D2 until after the finger of the key corresponding to the line number 6 has actuated through engagement with the brushes the solenoids that will ensure the wetting and the printing of the line 9 and further of the line 10 by virtue of the length of the brushes. After lines 9 and 10 have been printed the sheet will be further carried Without any printing effect upon it.

The same will be true for the series of sheets upon which the heading and the lines corresponding to the second delivery will have to be printed, and so on.

As many changes could be made in the above construction, and many apparently widely different embodiments of this invention would be made without departing from the scope of the claims, it is intended that all matter contained in the above description and following claims or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. Thus the electrical contacts may be replaced by any electronic device or others.

What I claim is:

1. A solvent operated duplicating machine including wetting means for wetting the blank sheet to be printed and effective across the entire blank sheet, pressing means for pressing said blank sheet against the transfer sheet and also effective across the entire blank sheet, a drum rigid with the conventional rotary transfer sheet carrying roller, and two adjacent peripherally arranged series of fingers, a pair of adjacent fingers consisting of one from each series being placed to correspond with the printed lines on the transfer sheet, one of said series of fingers being adapted to control said wetting means while the other series of fingers is adapted to control said pressing means, each finger of both said series of fingers being adapted to be selectively placed either into an operative or into an inoperative position on said drum, a wetting means activating member positioned in the path of said series of fingers adapted to control said wetting means when said fingers are in operative position, a pressing means activating member positioned in the path of said other series of fingers adapted to control said pressing means when said latter fingers are in operative position, said pressing means activating member being peripherally offset with respect to said wetting means activating member so that said pressing means activating member is actuated by a finger of any pair of fingers a predetermined time after said wetting means activating member has been actuated by the other finger of said pair of fingers, whereby pressure is applied on thesheet on the previously wetted portion of said sheet.

2. A solvent operated duplicating machine including wetting means for wetting the blank sheet to be printed and effective across the entire blank sheet, pressing means for pressing said blank sheet against the transfer sheet and also effective across the entire blank sheet, a drum rigid and coaxial with the conventional rotary transfer sheet carrying roller, a plurality of cylindrical recesses extending in said drum parallel with. the axis of said drum and located close to the periphery of said drum, each of said cylindrical recesses opening outwardly through a radial slot provided in the peripheral surface of said drum, a plurality of cylindrical keys mounted for sliding fit in said cylindrical recesses respectively, two fingers rigid with each of said keys and extending outwardly radially of said drum through said slots, said two fingers being spaced apart longitudinally of said keys, said keys being adapted to occupy in said cylindrical recesses two longitudinal positions, namely an operative position and an inoperative position, all the keys set into their operative position having their fingers intwo distinct operative planes at right angles to the drum axis and all the. keys set into their inoperative position having their fingers in two other distinct inoperative planes also at right angles to the drum axis, the fingers in one of said operative planes being adapted to control said wetting means while the fingers in the other of said operative planes are adapted to control said pressing means, a wetting means activating member positioned in said operative plane containing said fingers adapted to control said wetting means in the path of said fingers, a pressing means activating member positioned in said other operative plane containing said fingers adapted to control said pressing means in the path of said fingers, said pressing means activating member being peripherally offset with respect to said wetting means activating member so that said pressing means activating member is actuated by a finger of any of said keys a predetermined time after said wetting means activating member has been actuated by the other finger of said key concomitantly with rotational movement of said drum, the fingers positioned in said inoperative planes having no effect upon said activating members, whereby pressure is applied on the sheet on the previously wetted portion thereof.

3. A solvent operated duplicating machine including a transfer sheet carrying roll adapted. to be rotatively driven, wetting means for wetting the blank sheet to be printed and effective across the entire blank sheet, a pressing roll for pressing said blank sheet against the transfer sheet and also effective across the entire blank sheet, a plurality of wetting cam means adapted to control said wetting means, a plurality of pressing cam means adapted to control the pressure action of said pressing roll, said cam means being adapted selectively to assume two positions, namely an inoperative position and an operative position in which they effectively control the corresponding wetting means and pressing roll in timed relation with respect to the position of said sheet to be printed relative to said wetting means and pressing roll, and a permanent rotational driving connection between said transfer sheet carrying roll and said pressing roll, said connection consisting of two rubber-like discs respectively secured on the spindles of said two rolls in a common radial plane and having diameters slightly in excess of the respective diameters of said rolls, the arrangement being such that, when said pressing roll is pressed against said transfer sheet carrying roll, said rubber-like discs are slightly crushed and said rolls come into mutual pressing engagement, whereas, when said pressing roll is not pressed against said transfer sheet carrying roll, a gap is left between said two rolls while said rotational driving connection, however, is maintained, whereby the sheet to be printed is continuously fed through the machine and pressed against the transfer sheet only at locations of the lines selected by said wetting and pressing cam means.

4. A solvent operated duplicating machine including a transfer sheet carrying roll adapted to be rotatively driven, wetting means for wetting the blank sheet to be printed and effective across the entire blank sheet, a pressing roll for pressing said blank sheet against the transfer sheet and also effective across the entire blank sheet, a plurality of wetting cam means adapted to control said wetting means, a plurality of pressing cam means adapted to control the pressure action of said pressing roll, said cam means being adapted selectively to assume two positions, namely an inoperative position and an operative position in which they effectively control the corresponding wetting means and pressing roll in timed relation with respect to the position of said blank sheet relative to said wetting means and pressing roll, feeding means adapted to feed the blank sheet between said transfer sheet carrying roll and said pressing roll, and feed cam means to feed the blank sheet selectively during printing and non-printing intervals in the rotation of the transfer sheet carrying roll adapted to control said feed means in predetermined relation to the position of said blank sheet with respect to particular locations on the periphery of said transfer sheet carrying roll, whereby selected portions of said transfer sheet may be printed at predetermined locations on said blank sheet.

5. A solvent operated duplicating machine as defined in claim 4, wherein said blank sheet feeding means include a feed roll in permanent rolling engagement with said pressing roll, said blank sheet being adapted to be inserted between said feed and pressing rolls whence it is thereafter fed between said pressing and transfer sheet carrying rolls, the spindles of said transfer sheet carrying roll and said pressing roll respectively having secured thereon two rubber-like discs in a common radial plane and of diameters slightly in excess of the respective diameters of said rolls, said pressing-roll being adapted to assume three selective positions, namely a first or printing position in which said pressing roll is pressed against said transfer sheet carrying roll under the control of said pressing cam means, said rubber-like discs being slightly crushed and ensuring a rotational drive between said transfer sheet carrying roll and said pressing roll and hence said feeding roll, a second so-called feeding position in which said pressing roll is positioned a very short distance away from said transfer sheet carrying roll while said rubberlike discs are still in driving rolling engagement, whereby said pressing cam means being in inoperative position no matter is printed onto the blank sheet which, however, is still being fed on, and a third position in which said pressing roll is positioned a somewhat longer distance away from said transfer sheet carrying roller when said feed cam means are in inoperative position, whereby, upon continued rotational movement of said transfer sheet carrying roll, said pressing roll and hence, said feed roll are 10 not rotatively driven by said rubber-like discs now sepa rated.

6. The combination of claim 2 with a circular disc manually shiftable on the drum spindle and adapted to axially engage endwise said keys for moving said keys from their operative position to their inoperative position when said disc is manually shifted in the proper direction.

7. The combination of claim 2 wherein said wetting means activating member and said pressing means activating member are electrical contacts, and wherein said wetting and said pressing means each include a control solenoid arranged in an electrical circuit adapted to be completed by said contacts respectively for energization of said solenoids from a source of electric power.

8. The combination of claim 2 wherein said wetting means activating member and said pressing means activating member are adapted to be actuated by the respective fingers through the medium of arcuate members the length of which is equal to the distance between the tips of two successive fingers in said planes.

References Cited in the file of this patent UNITED STATES PATENTS 615,107 Schwarzchild Nov. 29, 1898 2,034,208 Ritzerfeld Mar. 17, 1936 2,380,004 Wilderson July 10, 1945 2,536,276 Gretchikhine J an. 2, 1951 2,536,604 Jagger Ian. 2, 1951 2,539,839 Jagger Jan. 30. 1951

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