US2016855A - Stencil printing apparatus - Google Patents

Description

Oct. 8, 1935.

H. P. ELLIOTT STENCIL PRINTING APPARATUS 9 Sheets-Sheet 1 Filed NOV. 10, 1933 I, I dvnulllllllllllJlll 11km! I INVENTOR HARMON R ELL/OTT ATTORNEY Oct. 8, 1935. H. P. ELLIOTT STENCIL PRINTING APPARATUS 9 Sheets-Sheet 2 Filed Nov. 10, 1955 INVENTOR HARMON P. ELLIOTT ATTORNEY Oct. 8, 1935. H. P. ELLIOTT STENCIL PRINTING APPARATUS Filed Nov. 10, 1956 9 Sheets-Sheet 5 INVENTOR HARMON P. ELL/0 TT ATTORN EY 9 Sheets-Sheet 4 Filed Nov. 10, 1933 INVENTOR HARMON F. ELL/0T7 W ATTORNEY Oct. 8, 1935.

H. P. ELLIOTT STENCIL PRINTING APPARATUS Filed NOV. 10, 1933 Q 9 Sheets-Sheet 5 INVENTQR HARMON I? ELL /0 T7' BY ATTORNEY Oct. 8, 1935. ELLIOTT I 2,016,855

STENCIL PRINTING APPARATUS Filed Nov. 10, 1933 9 Sheets-Sheet 6 INVENTOR HARMON E ELL/0T7 [55 BY ATTONEY IE Oct. 8, 1935. H. P. ELLIOTT 2,016,855

STENCIL PRINTING APPARATUS Filed Nov. 10, 1953 9 Sheets-Sheet '7 INVENTOR HARMON F. ELL/0 7'7' ATTORNEY Oct. 8, 1935. H, P. ELLIOTT STENCIL PRINTI NG APPARATUS Filed Nov. 10, 1935 9 Sheets-Sheet 8 INVENTOR HARMON B ELLIOTT wagm ATTORNEY Oct. 8, 1935.- H; P. ELLIOTT 4 STENCIL PRINTING APPARATUS 9 Sheets-Sheet 9 Filed Nov. 10, 1933 IIIIIIIIIIII;

lail/1111111111110 I INVENTOR HARMON F, ELLIOTT ATTORNEY Patented Oct. 8, 1935 UNITED STATES PATENT OFFICE Application November 10, 1933, Serial No. 697,407

12 Claims.

This invention relates generally to addressing or other printing apparatus comprising a flat stencil, or more usually, a. series of card stencils.

The object of the present invention is the production of a selective stencil printing apparatus of the utmost flexibility in use, in that it maybe easily adjusted (1) to print consecutively from each successive stencil fed from the magazine, or, (2) to select certain stencils only and print 11 once from each of such stencils, skipping all others, or (3) to print two or more times from all the stencils fed from the magazine, or (4) to select certain stencils only and print two or more times from each of those, skipping all others, each of 1 such varied methods of operation resulting from a simple readjustment of one or more elements of the entire combination constituting the operating unit. While this apparatus can be used on any kind of an addressing machine, I have herein 20-, illustrated it as applied to a novel form of flat pad mechanism, on which an application Ser. No. 5944 for patent on an addressing machine, and which is a continuation in part of the present application, has been filed under date of Feb. 11, 1935.

The best form of apparatus at present known to me for practicing my invention as above outlined and obtaining the results above recited, is illustrated in the accompanying nine sheets of T drawings, in which:

Fig. 1 is a partial plan view of the apparatus, with parts removed and others broken away.

Fig. 2 is a supplemental plan view showing most of the remaining portions of the. apparatus with parts broken away and others in section.

Fig. 3 is a partial rear view of the apparatus showing portions of the selective and repeatprinting mechanisms.

Fig. 4 is an end elevation showing the same parts appearing in Fig. 3.

Fig. 5 is a detail cross section on line 5-5 of Fig. 3; and,

Fig. 6 is a detail end elevation taken at the point indicated by the arrow 6 in Fig. 3.

Fig. 7 is a cross section of the essential portions of the printing mechanism taken on line 'l'I of Fig. 8.

Fig. 8 is .a front elevation of the same parts.

Fig. 9 is another detail section of the essential parts or the printing mechanism, taken on line 3-9 of Fig. 8, the printing platens being shown separated.

Fig. 10 is a similar View with the platens in closed position, i. e. that of completed contact.

Fig. 11 is a detail section of a portion of the inking mechanism, taken on line II--II of Fig. 7; and,

Fig. 12 is a detail cross section on a larger scale taken on the same plane as that of Fig. 10, but showing the printing platens at the moment of 5 their initial contact.

Fig. 13 shows a camfor triplicate printing.

Throughout the drawings like reference characters refer to like parts.

Referring to Figs. 7, 9, 10, and 11, which illus- 10 trate the printing mechanism, the same may be described as follows:

i is the table of the machine supported in any desired manner, as by legs, one of which is shown at 3i. On this table is pivoted at 3 a vibrating 15 frame generally indicated at 2. The pivot shaft 3 is mounted on bracket 4 fastened to the under side of table I, and projecting up through the opening 2| therein, one of the holding bolts for bracket 4 being shown at 5. A pressure arm 6 is cast on frame 2, and carries at its free end the platen I which has a flat face composed of rub ber or other elastic composition. 8 is an arm de pending from the frame 2 and connected by pivoted link 9 to the swinging member II! which is pivoted at II on the supporting strut I50, alsomounted in the bracket 4.

The usual grooved stencil guides along which a series of stencils S are slid into the printing zone between the lower platen I3 and the upper platen I are shown at I2, I2. Platen I3 is sup ported on the free end of the swinging arm I4 pivoted to bracket 4 at I5, and I6 is a roller, the journal of which serves as a pin to connect I3 to It, and which roller is supported on the cam arm ll which is pivoted at I I, being integral with the arm Ill.

The swinging frame 2 has a horizontally extending slot I8 registering with a wider slot I9 in the housing 23 behind it and through which a sheet of paper P or other article on which printing has been done may be fed by means of fric-' tion feed wheels 22, operated by mechanism generally indicated at I in Fig. 1, which constitutes no part of the present invention. The lower 45 platen I3 is intermittently lifted by cam I! through the opening 20 in table I to meet the desceriding platen I, compressing the stencil S and the sheet P to be printed between them.

Ink is supplied to the under surface of platen 'I by roller 32 which is mounted in housing 34 pivoted on the lower end of vibrating frame 33 which latter is pivoted at 25, such pivot being supported by arm 23. A frame 24 also swings from pivot 25 and carries a series of inkdistribut- 66 ing rolls 28, the lower one of which comes into contact with roller 32 when the matter is moved to the right across the face of the platen I, and the upper one of which is in contact with the ink carrying drum 26 which is journalled at 21 on the arm 23. Frame 24 has a projecting lug 35 which rests against the adjustable stop screw 3I under the pull of spring 35. Spring 35 anchored on the swinging frame 33 and connected to the free end of pivoted housing 34 holds roll 32 up against the face of the platen 1 during its transit across the same. The vibrating frame 2 has a depending arm 3 which is connected by pivoted link 9 to the swinging member II], which has a stop lug I35 adapted to engage the stationary strut E55, when the pull of spring i8 anchored on bracket 4 rotates frame 2 in a counterclockwise direction. When, however, the member I0 is swung on pivot ii in a clockwise direction, it gives a similar swinging motion to frame 2 and forces the upper platen l down while the cam I? engaging roller It forces the lower platen I3 upward. When t. e platen I rises on a reverse movement of the apparatus, partly under urge of said spring I8, the adjustable contact screw 35 on slotted connecting rod 44 rises with 4| and strikes the slide block 38' which is pivoted on frame 33 and located in slot 40 in said connecting rod, serving as a guide for the upper end of 4|. This gives a clockwise rotation to frame 33 and, when the platen i descends again, the spring 31 gives a reverse swinging motion to frame 33, these two motions reciprocating the ink roller 32 across the face of platen i.

As the arm 5 is subjected to great strains in this operation, which are transmitted to the skeleton casting forming a part of frame 2, I provide the additional bearing rollers 43 for frame 2, carried in the overhead housing 44, to take up some of these strains. 45 is a cover for the inking mechanism pivoted at 49 on the housing 48 and having a stop lug 46 which rests against the projecting end of arm 23. A distributing roll and an ink fountain shown at 4? together constitute a source of ink supply of the usual type as best shown in Fig. "I, depositing such ink on the cylindrical surface of drum 2B.

The mechanism for controlling the operation of the printing platens l and I3 is substantially the same as that illustrated and described in my copending application Ser. No. 704,440, filed December 29, 1933, and in Patent No. 1,183,385 granted to Sterling Elliott, April 23, 1916, as further modified and improved in the form shown :in my Patent No. 1,883,643, granted October 18,

1932. The prime moving mechanism comprises the hereinbefore mentioned swinging cam plate 55 pivoted at I I and oscillated by pitman 5| from a motor, not shown. 52 is a latch pivoted on swinging member I9 at 53 and carrying ,a lug I45 which is adapted to engage the notch I54 in the cam plate 53, then locking the swinging memher it] to the oscillating cam plate 55 and causing reciprocation of the'printing platens, as before described.

' stop 95 on the end of member ill. The movements and successive positions of the latch 52 are mainly controlled by the swinging trip-arm 59 which bears against the anti-friction roller 58 carried on the end of the latch. This trip-arm is mounted on shaft 69 and has two upwardly extending branches, one of which carries anti-friction roller I49 cooperating with cam I39 on plate 50, to give the arm 59 a counterclockwise rotation when the cam plate rises. This movement takes place against the resistance of spring 62. Another upwardly extending arm 53 integral with 59 cooperates with the latch 54 loosely carried by shaft 66. Latch 54 extends through an opening in 53, and, when its latch projection 65 engages the right hand surface of 63, it holds the arm 59 in contact with roller 58 and so forces the latch 52 out of engagement as shown in Fig. 4, with the result that the cam plate 50, when then rising and falling, operates the stencil feed mechanism only, and not the printing mechanism. Shaft 6!! is supported from bracket 5|.

If the latch 64 is held up so that the arms 63 and 59 are free to swing, the latter will be held during the greater portion of each cycle of operations away from latch roller 58 by spring 62 and the member It will be locked to cam plate 50 because spring !52 has pulled latch 52 into engagement with notch I64 in said cam plate 59. This will produce a printing operation during each cycle of operations and, if the stencils are fed continuously, there will be one printing operation performed with each. If, however, the printing operation is interrupted while the stencil feeding continues, certain of the stencils will be skipped, that is, will go through without being printed. Latch 64 may be thus held up by either one of two mechanisms, as follows:. Referring to Figs. 2 and 3, cam disk I9 is there shown journaled at H in housing 18 and cooperates with the cam nose 99 on the free end of latch 54. A ratchet wheel M is rigidly connected to cam 79 by the intervening notched lockingdisk I31, and all three are turned as a unit tooth by tooth by the pawl 13 carried by pawl lever 12 also journaled on pin II and oscillated by slotted pitman 15, to which 12 is pivotally connected. A crank arm I6 is rigidly mounted on the pivot pin 53 of latch 52 so as to swing with said latch and carries a pin H which slides in the slot shown in pitman 55, said slot being of such length that the pin I? will strike its upper end slightly before the conpletion of the upward movement of member l9, if latch 52 is in engagement, thereby vibrating pawl lever 72.' A spring locking pawl E38 bears on the locking disk I31, and the parts are so proportioned that by each operation of the ratchet mechanism the cam H3 will be moved far enough to shift the registration of the cam and nose 5;?! from low to high or vice versa. Consequently the latch 54 is allowed to drop into engagement with the arm 63, by one cycle of operations and lifted out of engagement at the n xt, if latch 52 is in engagement with notch I64, otherwise the pawl 13 is not operated and cam disk H3 remains at rest. Similarly the printing operation may be controlled by a selector apparatus of the general character described in my above noted co-pending application, comprising a frame I41 mounted on a vertical slide I48 and carrying one or more contact pins I49 which may or may not register with certain holes punched in the frame of each stencil S as such stencil comes under frame I41 and pins I49 are lowered into contact with the stencil. The slide I48 is raised and lowered by the oscillation of the crank 261 which is fast on shaft 266 (see Fig. 4.), and is connected by link 68 to crank 61 fast on shaft 66. Shaft 66 carries a dependent crank arm I26, on the free end of which is journaled the anti-friction roller I25 which cooperates with the cam I21 carried by the cam plate 56, so that the above described linkage is oscillated once during the latter part of each upward motion of the cam plate 56. An electric circuit is provided, one terminal of which, shown at I53 in Fig. l, is connected to the mechanism carrying and operating pins I49, all of which mechanism is insulated from the main frame of the machine including the stencil guides I2. If, therefore, the pin or pins I49 all pass through perforations In the frame of certain stencils, they will come in contact with the guides 12 and establish a circuit which includes the magnet 82 which, when energized, vibrates the armature lever 86 pivoted at 8 I the other arm of said lever extending under latch 64, as best shown in Fig. 3. This lifts the latch free from arm 63 so that spring 62 can pull arm 59 away from roller 58, and permit latch 52 to engage cam plate 56, so that on the next cycle of operations, when that particular stencil has been fed into the printing zone, the platens 1 and I3 will grasp the stencil and any sheet to be printed between them. I22 is a laterally proiecting lug on depending arm I26 to which spring I23 is connected so as to normally hold roller I25 in engagement with cam I21.

The cooperation of these two sets of mechanism produces the following results: The latch nose 69 resting on a depression in cam 16, the arm 59 is held against roller 58 and latch 52 is held out of engagement with cam plate 56, and no printing occurs, the stencils being skipped until one comes under the frame I41 having holes registering with pins I49, whereupon magnet 82 is energized and latch 64 is lifted, thus allowing latch 52 to engage so as to cause printing during the next cycle. The consequent raising of pin 11, resulting from the inwardly swung position of latch 52 and the upwardly swung position of crank arm 16 causes a lifting of pitman 15 and pawl 13 is actuated to rotate cam 16 and bring a high portion thereof under latch nose 69, thus continuing to hold up latch 64 and thereby leaving arm 59 free to be pulled to the left by spring 12, permitting latch 52 to remain in engagement during another cycle and print again from the same stencil. At the next cycle, however, a low portion of cam 16 is turned under latch nose 69, latch 64 again engages 63, and printing is stopped until another stencil with the same arrangement of holes comes along.

The stencils are fed along the grooved guides I2, I2 by means of a reciprocating slide 89 moving in and out under the stencil magazine 88 (best shown in Fig. 2), said slide having a projecting toe 99 on which the rear end of the bottom stenoil in the magazine will rest while the slide 89 forces it out along the guides I2 to the left under the pull of the slotted connecting rod 83, if the pin 81, carried by the slide 89, is in engagement with the offset portion 85 of the L- slot 84, 85, in connecting rod 83. The other end of 83 is pivoted to one arm of the bell-crank 56 which is directly operated and actuated by the engagement of head 55 with the cam slot 54 in cam plate 56. If the offset portion 85 of the slot is not in engagement with pin 81 the other portion 84 of the slot will permit connecting rod 83 to reciprocate idly on pin 81 and the stencil then in the printing zone will remain there, so that if the p1atens'1 and I3 are then actuated the repeat printing above described can be done.

83 is normally held in position to produce reciprocation of the slide by spring I6I, but can be forced into the position shown in Fig. '2 by cooperation of the friction rollers I66, I66 carried on the free end of swinging member 91 pivoted at 98 on an extension I64 from plate I44 which is fastened to the under side of table I. Member 91 is so swung intermittently, when desired, by cam disk II2, which is journaled on pin I63 set in housing I32, also carried by plate I44. On pin I63 are also mounted a ratchet disk I65 and a locking disk I I9, on which latter bears the spring locking pawl I26 mounted on plate I44. A pawl I66 carried by a swinging lever I61 cooperates with ratchet disk I65 to turn both cam disks I62 and I I2, with a step by step movement, whenever I61 is oscillated by reason of the fact that the pin I68, carried by its free end, engages the offset portion of the L-slot I69 in the fiat connecting rod II6, the other end of which is pivoted to the bell-crank 56.

Referring more particularly to Figs. 2, 3, 4, and 5, two oppositely extending crank arms H6 and I36 are shown pinned on shaft 66. The upper one, H6, is pivoted at its free end to a slide bar I I 5, moving on idling roll I3I between guides I2I and carrying on its free end anti-friction roll I I4 which bears on connecting rod II 6. When the arm 63 is released by latch 64 to produce a printing operation shaft 66 is allowed toturn slightly in a clockwise direction (looking at Figs. 4 and 5) and arm I I6 then moves in the same direction so that roll II4 pulls II6 away from pawl lever I61 (see Fig. 2) against the resistance of springs I21, so that the notch in L-slot I69 engages pin I68, and at the next vibration of bell-crank 56 pawl I66 and ratchet disk I65 rotate lower cam disk I I2 far enough to swing an elevation of such cam disk against the adjacent friction roller I66. This swings frame 91 toward connecting rod 83 against the tension of spring I6I and holds the longitudinal portion 84 of the slot in said connecting rod in line with pin 81 on stencil feeding slide 89. Consequently the rod 83 then reciprocates idly and the line of stencils in guides I2, I2 do not move, the one in the printing zone staying there for the second, or duplicate, printing operation. During such second printing, however, cam disk I I2 is again turned so that the roll I66 bearing on it drops into a depression under the urge of spring I6 I, and upon the succeeding operation the notch 85 in the connecting rod slot engages pin 81, and thereafter the feeding of stencils is resumed but no printing occurs if the next stencil to come under frame I41 does not have the combination of holes punched in it which have been punched in all stencils which are to be used in printing. This results because the magnet 82 is then not energized, latch 64 is left down, and arms 63, and 59 are held in position to disengage latch 52, for skipping such stencil and all succeeding stencils of the same character. The resultant position of shaft 66 also moves roll II4 away from connecting rod H6 and spring I21 pulls it over so that the notch in slot I69 is disengaged from pin I68 and the pawl I66 is no longer vibrated to turn cam disk II2 further, but leaves it with a low point against roll I66, so that the feeding of stencils continues until arm 63 is released by the co-action of another selected stencil and pins I49, another printing operation is initiated, and the stencil feed slide 69 is again'disabled for one cycle to again permit the duplicate printing therefrom above described.

While the apparatus shown and described produces duplicate printing, a mere substitution for cam .disks I0, I02, and H2 of similar disks having high portions of double width, such as disk I'I0, shown in Fig. 13, would produce triplicate printing, and sets of cams having crowns of still greater widths would increase the number of printings to any desired extent.

Upper cam disk I02 turns with H2 and, as a result, when the parts are in position shown in Fig. 2 and the stencil feed is temporarily disabled to permit duplicate printing, the roll I90 journaled on twisted connecting rod I I I is left on a high point of cam disk I02, and, such twisted connecting-rod III pivoted at its free end to crank II3 on shaft 66, holds the selector frame I 41 in raised position. This returns roller I25 on depending arm I26 out of contact with cam I2'I in spite of the pull of spring I23. The other end of III is guided by pin I03 which engages slot 90 on that end portion of II I.

Pawl I3 is fast on its pivot-pin H2 which carries an eccentrically located pin 9 (Figs. 3 and 6) which is connected by spring 93 with an anchorage pin 92'on pawl lever l2. This spring can be swung to either side of the axis of pin H2 with a snap-over action, serving in one position to hold the pawl in engagement with ratchet disk 14, and in the other position to hold the pawl out of such engagement. Similar adjustments of pawl Hi5 are rendered possible by snap-over spring I 30 anchored at one end to pin 229 on pawl lever IE1, and at the other end to pin I29 set eccentrically in pawl pivot pin i253. The movement of pawl lever I2 is limited by its stop pin I33 engaging one or the other end of notch I64 cut in journal II, as shown in Fig. 6.

The shaft 60 may be manually oscillated by link I I8 connected at its upper end to crank arm I36, and at its lower end to a skip pedal (not shown).

While I have hereinbefore described the platen 'I broadly as carried by arm 6, I prefer to employ a special mounting for it shown more in detail in Figs. 10 and 11, where the rubber pad is cemented to a plate 935 slidable in undercut grooves I51 in housing plate I55 which is hinged on pin H35 set in sub-frame i551 carried by arm 6. Plate H55 can be pulled out by grasping pin I72, and plate I56 can be given slight swinging adjustments on its hinge pin I60 by turning pressure screw I58 and holding screw ifil. The inking roll 32 has anti-friction rollers 55 journaled on sub-frame 34 and running on track rails 454 fast on plate I56.

ihe detail view, Fig. 6, of the ratchet-mechanism-operating cam-disk 76, shows a stop pin I53 carried on the boss of the pawl lever 72 and moving in the wide, shallow notch I62 cut in a cap plate I66 which is held on the end of the journal pin 'II of the cam and is prevented from rotating by the dowel pin I57. This limits the counterclockwise rotation of pawl lever 12 and holds up the slotted p-itman I 5 after the downward movement of the latch 52 has lowered pin ii away from the upper end of the long slot in said pitman.

The various methods of operation of the above described apparatus may be concisely explained as follows:

If both pawls l3 and M6 are swung back out of operative position all the cam mechanisms will be disabled, and if the cam disk I is then so turned that a high point will come under the nose 69 of the latch 64, the selector mechanism will also be disabled, and when the machine is started up it will operate as a. standard addressing apparatus after the manner of the mechanism described in the before mentioned patent to Sterling Elliott No. 1,186,385, by printing once for each stencil fed out of the magazine.

Again, if both pawls are turned back from operative position but cam disk to is turned so that the nose 55 of latch 5:3 rests on a low point, the selector mechanism will become operative and, when the machine is started, it will skip all stencils except those having the predetermined arrangement of holes, but will print only once from 15 each of such stencils, functioning as a straight selective addressing machine after the manner of the apparatus described in my hereinbefore noted co-pending application Serial No. 704,440.

If, however, pawl '13 alone is turned back out of operative position and earn it is turned so that a high point comes under the latch nose 69, while pawl m6 is left in operative position, the selector apparatus will again be disabled so that there will be printing at every operation of the machine, all the stencils being used. But inasmuch as the continual movement of the arm 59 into the posi tion permitting engagement of the latch 52 for effecting printing operates to pull. the connecting rod lie away from ratchet disk 505 so that the pin see on the ratchet lever i0? is continually engaging the offset notch in the L-shaped slots 4% in said connecting rod, this ratchet I 05 is continuously operated, thereby rotating, during each cycle, the lower cam disk H2 a distance of half a tooth, so that the stencil feeding slide connecting rod 83 is disabled after every other cycle, thereby disabling the stencil feed apparatus and leaving each stencil in the printing zone for a repetition of the printing operation therewith. As aresult every name and address will be printed twice.

Finally, if both pawls i3 and I05 are left in operative position, as previously described and shown in the drawings, the apparatus will automatically operate in the manner heretofore explained in detail, and duplicate printing with each selected stencil will be performed, while all others will be skipped.

The use of the upper. cam disk i112 and the twisted connecting rod ill actuated thereby to disable the selector apparatus whenever duplicate printing is being done is not absolutely necessary, as the second lowering of the pins its for a second engagement with the stencil'in selective position, while the second printing is being done with the stencil ahead of it in. the printing zone, does not interfere with the desired operation of the mechanism, The disabling of the selector mechanism at this time, however, saves a certain amount of wear on the apparatus and drain on he batteries supplying current to the selector circuit, and also diminishes the possibilities of the occurrence of sparking at the contacts. I am aware, of course, that in the construction of addressing mechanisms comprising an ink-applying mechanism operating in a. printing zone to which a series of legend-bearing elements, either card stencils or type bearing plates, are fed in succession for cooperation in the printing operation, 7 means have heretofore been provided for skip ping some or such stencils or plates, either by manual control or by the actuation of an automatic selector mechanism, or for repeat printing from some or all of such legend-bearing elements under manual control, but the present invention is believed to embody the first successful attempt to produce a machine which will run continuously and do one or another or several of these things automatically whenever first manually adjusted for the particular purpose selected bythe operator.

The particular method of operation of the swinging platens which produces the progressive increase of the area of contact between them and the stencil and paper, which renders the fiat pad printing with stencils possible and constitutes an important feature of my invention, (not herein claimed) is illustrated in somewhat exaggerated form in Fig. 12. This result is attained in two ways; which are cumulative in the apparatus here shown.

Evidently, if the two platens were swung from the same hinge axis, or from two axes both of which lay in the plane of contact of the two platens, and the slight thickness of the film of ink on one platen were disregarded, the two platen surfaces would come into complete contact throughout their opposing areas at the instant that both, or the latest one to arrive, came into such plane of contact, and the same difficulty with the trapping of air bubbles would occur substantially as though one platen were stationary and the other one was forced down on it by a plunger traveling on a line at right angles to the surface planes of the two platens.

This result I avoid according to my invention by using an elastic surfacing material (such as shown at l) for at least one of the pads, and then so adjusting the parts that the common plane of contact is parallel to the surface of the elastic platen only when that elastic material has been compressed by contact pressure to the extent desired for satisfactory printing. As a result, when the platens are approaching one another and the initial contact occurs, they are (due to the swinging motion of one or both) in relative positions such that their surface planes are slightly inclined one to another and the initial contact then occurs only along the mathematical line at one edge of at least one platen surface, and from there extends progressively to the other edge as the movement of compression of the elastic material forming platen l is completed.

Furthermore, I exaggerate the above action to a certain extent, and also produce a slight wiping action of one platen on the other, by separating their respective hinge axes 3 and I5 (see Fig. 9) in a direction substantially at right angles to their common plane of ultimate completed contact. It will be seen on looking at Fig. 9 that as the platen l3 rises toward the stencil S (which must be in the plane of final contact between is and. 1) not only will the lefthand edge of platen l3 touch the stencil before the rest of its surface comes into contact after the completion of such contact, but during the completion of its upward movement there is a slight component of horizontal movement of said platen to the left due to the axis !5 about which it is pivoting being considerably below the plane of stencil S. This slight wiping'motion of the platen l3 also tends to squeeze out and wipe away the air bubbles by dragging them to the left, as distinguished from being slapped up on them simultaneously at all points, as would be the result if the platen I3 were being lifted up on a vertical plunger.

The particular advantage of having the operative portion of the upper platen I removable in through the machine will then be printed. Thus, 1t)? if it were desired to make up a list of all the names, omitting the addresses, it would not be necessary to make up a whole new set of stencils, but the addressing stencils could be used with a rubber pad l which had been cut away so that 15 only the line of the stencil which prints the name would come into use at each operation. 7

Having described my invention, I claim: 1. In a stencil printing apparatus comprising a swinging ink-carrying platen, a series of card 2i) stencils, means for swinging said platen into, and out of, contact with any stencil then in the printing zone, and mechanism for feeding said stencils one by one into said zone, together with a device for causing said platen to effect printing opera- 25 tions only when selected stencils come into said zone, the combination, with said above described apparatus, of mechanism manually adjustable so as to produce repeat printing with each of such selected stencils automatically while in such 30 adjusted condition.

2. An apparatus such as defined in claim 1 combined with additional mechanism manually adjustable so as to disable said selective device during each such repeat printing operation auto- 35 matically while in such adjusted position.

3. A combination such as defined in claim 1 in which said platen swinging means is controlled jointly by said selective device and by a constituent element of said platen swinging means, 40 whereby, whenever said selective device initiates a printing operation, said last mentioned element will automatically repeat it.

4. A combination such as defined in claim 1 in which said automatic mechanism for producing 45 repeat printing includes a cam disk which may control said selective device, and a pawl and ratchet mechanism for rotating said cam disk.

5. A combination such as defined in claim 1 in which said adjustable mechanism for producing 50 repeat printing includes a cam disk which may control said selective device, and a pawl and ratchet mechanism for rotating said cam disk, said pawl being temporarily adjustable at will into an inoperative position; whereby said cam 55 may be left at rest while other portions of the entire machine continue in operation.

6. A combination such as defined in claim 1 in which said adjustable mechanism for producing repeat printing comprises means for tem- 60 porarily disabling said stencil feeding mechanism; whereby the stencil then in the printing zone is permitted to remain there for such repeated printing operation.

'7. A combination such as defined in claim 1 in which said adjustable mechanism for producing repeat printing comprises means for temporarily disabling said stencil feeding mechanism; whereby the stencil then in the printing 70 zone is permitted to remain there for such repeated printing operation, said last mentioned means comprising a continuously reciprocating member, a stencil feeding slide, a connecting-rod permanently pivoted to said member but detach- 7 ably connected to said slide, and a means adapted to make or break said connection.

8. A combination such as defined in claim 1 in which said adjustable mechanism for producing repeat printing comprises means for temporarily disabling said stencil feeding mechanism; whereby the stencil then in the printing zone is permitted to remain there for such repeated printing operation, said last mentioned means comprising a continuously reciprocating member, a stencil feeding slide, a connectingrod permanently pivoted to said member but detachably connected to said slide, and a means adapted to make or break said connection, comprising a cam disk and a pawl and ratchet mechanism for intermittently rotating said disk.

9. A combination such as defined in claim 1 in which said adjustable mechanism for producing repeat printing comprises means for temporarily disabling said stencil feeding mechanism; whereby the stencil then in the printing zone is permitted to remain there for such repeated printing operation, said last mentioned means comprising a continuously reciprocating member, a stencil feeding slide, a connecting-rod permanently pivoted to said member but detachably connected to said slides, and a means adapted to make or break said connection, comprising a cam disk and a pawl and ratchet mechanism for intermittently rotating said disk, said pawl being manually movable temporarily into and out of operative position.

10. A stencil printing machine having a printing zone, a device for successively feeding a series of legend bearing elements one after the other into said zone, mechanism adapted to cooperate with such element while in said zone to print the legend borne thereby, and means for disabling said mechanism whenever selected members of such series approach said zone, combined with apparatus for causing said mechanism to repeatedly print each of such legends, each said disabling means and said repeat printing apparatus being manually adjustable to inoperative condition; whereby said machine may be adjusted to print from all stencils once, or to repeat printing from all stencils, or to select stencils and print one, or more times from each of those.

11. An apparatus such as defined in claim 10 in which each said disabling means and said repeat printing apparatus comprises a pawl and ratchet wheel mechanism in which each pawl is provided with a snap-over spring for holding it in either operative or inoperative positions.

12. An apparatus such as defined in claim 10 in which each said disabling means and said repeat printing apparatus comprises a pawl and ratchet wheel mechanism in which each pawl is provided with a snap-over spring for holding it in either operative or inoperative positions, and also comprises a rotary cam disk moving with its associated ratchet wheel; whereby, after either pawl has been placed in inoperative position, the cam otherwise actuated by it may be manually adjusted so as to cooperate in producing the desired result while at rest.

HARMON P. ELLIOTT.

Images