US2355930A

US2355930A - Stencil printing mechanism

Info

Publication number: US2355930A
Authority: US
Publication date: 1944-08-15
Anticipated expiration: 1961-08-15

Description

Aug. 15, 1944. w. THORNE STENCIL PRINTING MECHANISM Filed April 11, 1941 6 Sheets-Sheet l Aug. 15, 1944. w. THORNE STENCIL PRINTING MECHANISM Filed April 11,

MMM

Aug. 15, 1944.

w. THORNE STENCIL PRINT ING MECHANI SM Filed April 11, 1941 6 Sheets-Sheet 3 INVENTOR \N RRD Maw E BY \WMW ATT RNEYS Aug. 15, 1944. w. THORNE STENCIL PRINTING MECHANISM 6 Sheets-Sheet 4 Filed April 11, 1941 11/ III! 111/111 ILLLFII 11/11 1 11M INVENTOR N RED {\m E -L OR E115 ,I v if a Aug. 15, 1944. w. THORNE 2,355,930

STENCIL PRINTING MECHANISM Filed April 11, 1941 6 Sheets-Sheet 5 INVENTOR WARD H4 5 BY E i u A TToRNEY Aug. 15, 1944. w. THORNE 2,355,930

STENCIL PRINTING MECHANISM Filed April 11, 1941 6 Sheeis-Sheet 6 INVENTOR Wm 10v m;

H K FI ORNEYS Patented Aug. 15, 1 944 I -2,355,93oi

2,355,930 s'rnncn. PRINTING micnam'sm Ward Theme,

mesne York. N.

Westport, Conn, assignor, by

to Linen Guild, Inc., New,

Y., a corporation of New York Application April 11, 1941, Serial No. 388,017 18 Claims- (Cl. 101-123) The present invention relates to stencil printing mechanism and embodies, more specifically, an improved form of stencil printing device wherein stationarily located material to be printed upon is traversed by a printing mechanism that is advanced periodically and located auto- I matically in successive printing positions. A device of this character is shown and described in the application of Wierk and Montague Serial No. 319,856 and the present invention embodies certain structural and operating improvements upon the foregoing mechanism.

More specificall an object of the present invention is to provi e an improved driving mechanism by means of which the movements of the stencil mechanism may be effected with precision and alacrity. v

A further object'of the invention is to provide an improved device by means of which the movable stencil carriage may be located accurately in a series of printing positions.

Yet another object of the invention is to provide an improved stencil operating mechanism by means of which the movements of the stencil with respect to the material to be printed may be efiectively controlled.

A further object of the invention is to. provide an improved mounting mechanism for the carriage upon which the carriage is mounted, by means of which the carriage may be located transversely of its direction of movement.

A further object of the invention is to provide an improved color applying mechanism by'means of which the application of color to the material to be printed is accomplished effectively.

The foregoing objects are attained by means 01 fluid driving mechanism for actuating not only the movement of the carriage along the material t6 be printed but also the raising and lowering of the stencil frame and the locating mechanism by means 01' which the carriage is located in successive printing positions. Further structural improvements are embodied that will be described in greater detail hereinafter and that attain the objects hereinabove recited, as well as other objects that will be apparent to those skilled in the art upon reading the following specification in connection with the accompanying drawings, wherein:

Fig. i is a plan view of a machine constructed in accordance with the present invention.

Fig. 2 is a viewin side elevation, partly broken away and in section, showing the device of Fig. 1.

P18. 3 is a'view in longitudinal section, taken on the line 3-4 of Fig. 1 and looking in the direction of the arrows.

Fig. 4 is an enlarged detail view, showing a part of the carriage moving mechanism of Fig. 2.

Fig. 5 is a view in section, taken on the line 55 of Fig. 4 and looking in the direction of the arrows.

Fig. 6 is an enlarged view in section, taken on line 6- of Fig. 1 and looking in the direction of the arrows.

Fig. 'I is a view in section, taken on the line 1-1 0! Fig. 4 and looking in the direction of the arrows.

Fig. 8 is an enlarged view in section, taken on the line I--8 of Fig. 1 and looking in the direction of the arrows. 4

Fig. 9 is an enlarged view, taken on the line 9-8 of Fig. 1 and looking in the direction of the arrows.

Fig. 10 is a view in section, taken on the line Ill-ll oi Fig, 1 and looking in the direction of the arrows.

Fig. 11 is a view in section, showing one of the valves of the fluid system utilized by the present invention.

Fig. 12 is an enlarged detail view, in section, showing the cushioning mechanism provided for the carriage drive.

Fig. 13 is a view in section, taken on the line, |a-|: of Fig. 12 and looking in the direction of, the arrows.

Fig. 14 is a diagrammatic view of the electrical system used by the present invention.

Fig. 15' is a diagrammatic view of the fluid system used by the present invention.

Referring to the above drawings and particularly to Figs. 1 and 2, it will be observed that an elongated table I is provided upon which the fabric 2, to be printed upon, is secured in a suitable fashion. At opposite sides of the table i, rails 3 are secured, these rails being formed of inverted V-shape as illustrated in Figs. 5 and 'Z, in order that a movable carriage 4 may be suitably positioned and accurately located upon the tablej The rails are formed with flanges 3' which are suitably secured to the table and are engaged by rollers 5, mounted upon brackets 6, mounted upon the bottom of the frame of the carriage l.

These brackets 6 are located at the four corners of the frame and the axes of the rollers preferably lie parallel to the angular sides of the track 1 as illustratedin Fig. 7. The foregoing mounting of the carriage upon the rails provides lateral stability for the carriage and insures proper location upon the table.

.i'ormed with sleeves is to slide on the The boss Within the carriage 4 there is provided a stencil frame 1 which is pivoted at one end upon a pivot shaft 8 carried the carriage 4.

upon the fabric 2. The stencil box may be located upon channels 12 carried by the frame 1 and color is may be applied through the stencilby means of paddles I4 and II in a manner to be described hereinafter. I

In order that the carriage 4 may be advanced along the table to successive printing positions, the'carriage is provided with upper and lower guide rods i6, secured to the carriage by means of front and rear brackets l1 (Figs. 2 and 4). Slidable upon the guides I3 is a cross-head l3 guides II. The cross-head I8 is formed with a boss 20 (Fig. thatis formed with a vertical channel within which a vertically slidable plate- 2| is received. 20 is also formed with a horizontal within which a plate 23 is slidable, the plate 23 being formed with slots 24, receiving pins 25 that are carried by the boss 23, in order that the plate maybe suitably guided. The plate channel 22 23 is also formed with an angular slot 26 receiving a pin 21 formed on the plate 2i. In this fashion, longitudinal movement of the plate 23 will cause vertical movement of the plate 2| between the limits afforded by the extremities of slot 26 The plate 2| is formed, at its lower extremity, with one or more teeth 23 that are adapted to engage between the rollers 23 carried by links 33 of a chain that is secured to the table at the side of one of the tracks 3. Certain of the links 33 are formed with flanges 3| in order that the chain may be secured effectively in position.

The cross-head i3 is moved slidably along the guides It by means of-a connecting rod 32 formed with a piston 33 (Fig. 2) received within an elongated cylinder 34. Fluid is introduced into the cylinder 34 through )DZ ction 35 at one end of the cylinder and connection 33 at the other end thereof. In this fashion, the piston 33 may be moved to the right as viewed in Fig. 2, and with respect to the carriage, at which time the crossupon a. platform. 3 formed upon head i3 is moved on the guides it. In the next phase of operation, the piston and crcssqhead are locked with respectto the track and the cylinder moves to the right, advancing. the carriage and guides with respect to the cross-head. Inasmuch as movement 01' the cross-head II to the left as viewed in Fig. 4 will first result in the lowering of the teeth 23 to engage the chain 30, continued movement to the left will result in'advancing the entire carriage to the right in the desired fashion.

Movement of the carriage to the right as above descrbied is limited by means of a collar 31 (Fig. 4) carried upon a control rod 33,. slidably received in bosses 33 formed upon the cross-head it. A bracket 43 is adjustably mounted upon the uides l3 and secured clamping bolts 4i. ceives the control against which the in position by means of The bracket 40 slidably rerod 33 and serves'as a limit collar 31 engages to arrest the pin illustrated in Fig. 9. at 44 and is formed with a piston .43 received:

moving the control rod 33 into supplementary cylinder 42 (Fig. 12).. Continued movement or the piston'in the cylinder 34 advances the control rod 33 into the cylinder 42 to progressively cut oil ports 43 and thus restrict the escape of fluid from the left-hand end of the cylinder 34 into the fitting 33. This provides a. cushioning effect to absorb the shock of arresting carriage.

A flow of fluid in the reverse direction, that is,

entering the cylinder 34 through the fitting 33 causes a slow return movement of the piston 33 until the cross-head it strikes a collar 31' on the control rod 33 to move the control rod to the right as viewed in Fig. '12. This causes the apertures 43 to b opened and ready for the cushioning operation on the next return of the crosshead.

The bracket in cooperates with a scale 40 that is mounted on the carriage and, by means of an indicator arm 43, indicates the movement of the carriage during each cycle of operation. The travel of the carriage can be adjusted by adjusting the position of the bracket 40 as well as the collar 31.

Upon initial movement of the piston 33 to the right in the cylinder 34 as viewed in Fig. 2, the pin 21 will beraised bythe slot 23 and the teeth 28 will be disengaged from the chain 30. Continued movement of the the cross-head it along the guide rods II to the position illustrated in Fig. 4, at which time the carriage will be maintained in such position during the, printing operation'by means of a locking This locking pin is shown within a cylinder 48. Fluid may be introduced into the cylinder by means of

fittings

41 and 43 in order that the piston 45 may be moved in opposite directions. The pin 44 is provided with a tooth 49 that is adapted to engage between the adjacent rollers of the chain 30 so that the carriage will be locked in the desired position. The chain thus serves as a locating mechanism for the carriage.

In. order that the mechanism may be sealed effectively against the escape of fluid from the fluid system, the cylinder 46 is provided with a sleeve to threadedly engaged therewith, formed with a chamber 5i within which multiple seals 62 may be received.

parent. Beneath the seals 52 there is provided a plate 53 having a peripheral groove 54 connected to a discharge fitting 55 that is connected to a sump as hereinafter described. A lower seal 53 is provided beneath the plate 53 to prevent the The operation of the locking pin 44 will be described in greater detail hereinafter in connection with the cycle of operation of the machine.

In order that the color l3 may be applied effectivelyio the stencil by means of the paddles i4 and II, the paddles are mounted upon rods II that are siidably received in sleeves 59 pivoted at Oil on a frame 6|. Spring 62 normally urge the paddles downwardly against the stencil I i and the sleeves "are formed with arms 33 that are provided with set screws 64 adapted to engage against stops 3! in order to limit the angular movement oi the sleeves 33 about the pivots 34.

As will be apparent from Figs. 3 and 8, movethe movement of the piston will advance paddles in the positions shown in these figures and the paddle I4 will thus apply the color to the stencil. After the frame 4| reaches the extreme right-hand position and its movement is reversed (as will be described in greater detail hereinafter) the paddles will pivot about the pivot pins '3 and the right-hand paddle II will apply the color to the stencil during the movement of the frame I to the left as viewed in these figures. The paddles thus alternately serve to apply the color to the stencil and remain in parallel relationship during all such operations.

The frame is provided with upper rollers 34 (Fig. 6) and lower rollers 31. Upper rollers ride on a track 88 while rollers 31 engage the lower surface of a track 80. In this fashion. the vertical movement of the frame II is limited.

Through rods (Fig, 8) space the frame elements properly and, in order to mount the frame OI thereon, the through rods are located by means of plates H, the frame 6| being iournalled upon the lower through rod 10 and secured to the side through rods bymeans of straps 12.

The paddle frame assembly is moved longitudinaliy along the

guides

63 and 33 by means of an endless chain 13 that is connected to the opposite ends of the plates 1I, passing over the

sprockets

14 and 15. The lower stretch of the chain 13 is received between the guides 83 and 69. as illustrated in Fig. 6.

Sprockets '15 are mounted upon a drive shaft that is driven by means of a sprocket 11 which is driven by a chain 13 (Figs. 1 and 3) that is driven by a drive sprocket 13 mountedupon a shaft 80. The shaft is driven by means of a sprocket 0I that is driven by shafts 32 and 0 3 which, in turn, are driven by a worm and'worm wheel connection 04 that is driven by an electric motor 85.

The forward end 01' the stencil frame (the right-hand end as viewed in Figs, 1, 2.and 3) is raised and lowered by means of mechanism shown in Fig. 10. This mechanism includes a cylinder 06 that ispivotally carried by the carriage frame 4 at 01 and is supplied with

fluid fittings

33 and 39. A piston 50 is slidably mounted within the cylinder 06 and is connected to a connecting rod 3| that is pivotally connected at 92 to the stencil frame 1. A seal and return mechanism may be provided at the upper end of the cylinder as described in connection with the structure shown in Fig. 9 and the details need not be expanded at this point. It will be apparent that, depending upon the application of fluid pressure to either of the fittings 00 and 00, the piston and stencil frame will be raised or lowered. The manner in which this fluid pressure'is applied will be described hereinafter.

The rear end of the stencil frame is provided with brackets 93 (Figs. 1 and 2), these brackets being journalled upon the shaft 00 that is supported in eccentrics 94, pivoted at 05 upon brackets 00, carried upon the table 9. The eccentrics 04 are moved about the pivots 95 by means of a piston 91 that'is received within a cylinder 93 provided with fittings 93 and I00 which receive fluid in a manner to be described hereinafter. By controlling the application of fluid pressure sides of the iston 91 the eccentrics 94 raised and lowered.

One of the eccentrics 04 is provided with shoulders IIII and I02 to actuate respectively limit switches A and F as will be described in greater may be I20 between the bushings H5 and H1.

. associated mechanism thus provide a means for raising the rear end of the stencil box or frame during predetermined periods in the cycle of op-'- eration of the mechanism.

In order that the various operations hereinabove referred to may be accomplished, the present invention utilizes a fluid system which, in the device shown and described herein, consists of an oil system illustrated diagrammatically in Fig, 15 and including apressure tank or accumulator I03 within which a body of oil I04 is received, a column of air I05 being maintained above the oil. The oil I04 is maintained under pressure by means of a pump I03 driven by an electric motor I01 that is preferably reversible and may be controlled manually so that the tank may be emptied as it becomes oil-bound.

From the tank I03 a pressure line I08 supplies the oil under pressure to a plurality of valves I03, III, III and H2. These valves are all of similar design and are illustrated in Fig. 11 wherein valve I09 is shown as being formed with a casing I I3 and a valve rod I I4. The valve rod is formed with a central bushing H5 and bushings H8 and H1. Each of the bushings H6 and H1 may be provided with grooves III! to serve as seals in a manner which will be readily understood.

A reduced portion II! is thus formed between the bushings H5 and IIS and a reduced portion The valve rod I I4 is normally maintained in one position by means of a spring I2I that is seated upon a disc I22 carried by the rod and within a spring seat I23 which is formed in the casing I I3. Movement of the valve into the position shown in Fig. 11 is caused by the energization of an electromagnetic coil II as will be described in' greater to opposite detail hereinafter. The eccentric plates 04 and 13 casing II3 by means of detail hereinafter.

Fluid under pressure is introduced into the a conduit I24 and is adapted to be discharged therefrom through either of the conduits I25. Conduits I26 and I21 (Fig. 15) establish communication between the interior of the valve casing and cylinder through the fittings 59 and I00.

It will thus be seen that when the electromagnetic coil 11 is energized, the valve rod II4 will be moved into the position shown in Fig. 11 and fluid under pressure will flow from the conduit I24 throughthe reduced portion II9 to the conduit I26. This will cause the piston 91 to be moved. to the left as viewed in Fig. 15 and to elevate the rear of the stencil box. When the valve rod H4 is in its normal position, the fluid pressure is introduced through the conduit I21 to cause a movement of the piston 91 in the reverse position to lower the rear of the stencil box. In each such instance, the conduit I26 or I21 which does not receive fluid under pressure is connected to either of the discharge conduits I25 in a manner which will be readily apparent, thus relieving the appropriate side of the piston 91 from fluid pressure. 1

Connections of the above character are provided for each of the valves IIO, III and II2, the normal positions of the valve stems of these valves being such that fluid under pressure normally is maintained in conduits I20, I30 and I33, while conduits I29, I3I and I32 are connected to exhaust connections I25. A sump I34 is provided to' collect the fluid discharged from the several valves and pump I05 supplies the fluid from such sump to the tank I03 by means of a. pipe I35.

The electrical connections by means of which by means of a wire Ill;

relay coil V by means of a the fluid system above described may be controlled are lllustrated'ln, Fig. 14 wherein a rotary step switch is shown at I and provided with a rotor'lt having three contact arms'r, r and)". These arms are spaced equi-distantly about the rotorand are adapted to make connection with conducting segments s, s ands. The segments s and s are connected together by means of a wire I" and to a source of current by means of a wire Ill. The segment s is connected to a stepping relay Ill and to a suitable source of current by means of a wire Ill. For purposes of simplification, the source of current is assumed to be grounded in order that the circuits hereinafter described may be conveniently completed. The stepping relay I rangement by means of which the rotor B. may be advanced periodicallyto successive positions upon successive energization of the stepping switch.

The stepping switch I" is provided with con-' tacts that are connected in such fashion as to cause the rotor contactcrs r, 1- and r to advance through eight successive positions upon corresponding contacts before completing one cycle of operation. I

The stepp g switch is provided with a plurality 01' contacts, twenty-four in all. spaced circumferentially about the switch and arranged in three groups insofar as their cemed. The first group'of eight contacts is illustrated as contacts a, b, c, d, e, f, a and h. The

, second group of contacts is indicated at a, b, c,

d, e, I, g and k The third group of contacts is shown at 'ahb, c, d, c, f, and h. 1

It will be seen that contacts b, c'and d, and contacts I, a and )t'are connected together.

Contacts b, c and d are contacts 1. tr and h to relay coil II by means of a wire I; contacts d! to relay coil VI by means of a wire I; and contacts c and h to relay coils III and IV by means of wires Ill and Ill, respectively.

Contacts a, b, c, d, e", 1', a and h are connected to the respective limit switches A) B, C. D, E, F, G, and H by means of wires I41, I, I, "0,. III, III, I" and III. The relay coils V is provided with a drive arfunctions are conconnected to relay coil I a,sss,oso

' thus causes the relay .the conduit ill so that the rear pivot of the stencilboxislowered.

As soon as the rear pivot'ofthe stencil box is.

closes the limit switch lowered, the shoulder Ill A toenergise th coil Ill and step the arms of the switch It into the next position. In this position. arm renga'ges contact bto energize relay coil 1; r engages dead contact 11 and arm r engages contact b to connect the limit switch 28 with coil IIO. Energization of relay coil I causes the valve I II to supply fluids under pressure through conduit I to iitting 89, causing the front end of th stencil box to .be lowered. When the box is lowered, limit switch B is closed again energizing the. coillil .and stepping the switch R to the next tacts engage the series of c contacts. Arm 1' coil I tomaintain the front end of the stencil box down while arm r engages contact 1: to energize the circuit of motor it to advance th paddle frame steadily over the stencil. Arm engages contact 0' thus connecting the limit switch 0 in the coil Ito step the wire I42; contact c to E with the 0011 I".

and VI control a reversing switch R.S. to control said fleld windings may be connected to a source of current indicated at I! are illustrated in Fig.-

14 and need not be described in detail inasmuch as they are conventional connections forcircuit's oi thischaracter.

The operation of the mechanism is as follows: With therotary switch R. in the position illustrated in Fig. 14, switch arm 1' connects limit switch H to the stepping coil I while the carriage and stencil mechanism is advancing along the table toward the next printing position. When it reaches such position. the limit switch H is closed, energizing the coil I 39 and stepping the switch arms to the next position at which time arm r is on dead contact 0, arm r on dead contact a and arm r' on contact a, so that the of oil through conduit Ill. Moreover. relay coil II is deenerslzed to cause oil to be supplied to 76 reached the desired de-energized, th locating pin circuit with the coil I39 and, frame completes its forward motion, limit switch 0 is closed, again stepping the contacts of switch B into the at position. In such position, arm, 1' engages contact if to continue toenergize the relay coil I: arm 1' engages contact (1 to energize the relay coil VI to. reverse the direction of rotation of the motor II,- and arm 1- engages contact d to connect limit switch the motor ll; brings arms of the switch R into thee position. Since contact e is dead, the front end of the stencil box is elevated by reason of the normal position of the valve III. is also dead and contact e connects limit switch When the front end'of the stencil box is elevated. the limit switch E is closed. again stepping the switch Rinto the I position wherein arm r engages contact I to energize the relay coil 11; contact limit, switch l' to the; II and valve Ill cause directed to the cylinder nection of the box to fluid under pressure to be II .to cause the pivot conbe elevated to close the limit switch F and step the switch R around to the 0 Position.

In the a position, to maintain the relay coil II energized; the arm r engages contact a to energize relay coil IIIrand arm 1" engages contact a to connect the limit switch G to the coil III.

rear' pivot of the stencil box gis maintained elevated by the continued energization ofthe coil to energize coil III; and the arm r engages the limit switch H tothe contact 'h' to connect the coil Ill. In such position, the relay coil IV causes the valve III to be actuated to introduce fluid under pressure into the cylinder 34 andthus fiance the carriage toward the next printing It will be observed that, after the carriage has printing. position. and the position so that the conthe relay coil V- and close when the "paddle D in circuit, with the Contact e r engages dead contact and contact r eng gescontact P to connect the relay coil III. -Relay coil the arm 1' engages contact a In this position, the a is is raised the limit to advance the switch R to the de-energized. This permits the valve Ill tomove to its normal position and to supply fluid under pressure to the left-hand end of the cylinder 34 to advance the cross-head ii to the right in order that it will be ready for the next operation.

It will thus be apparent that the invention provides a completely automatic mechanism for advancing the stencil along the material to be printed, locating the stencil, applying. the ink, raising the stencil and advancing it to the next position.

While the invention has been described with specific reference to the structure described in the attached drawings, it is not to be limited, save as defined in the appended claims.

I claim:

1. Stencil printing mechanism comprising a work supporting surface, a carriage movable along said surface, stencil printing means on said carriage, an assembly comprising a piston element and a cylinder element, means to connect the assembly to the carriage, means on the assembly to engage the supporting surface, and means tointroduce a fluid under pressure into the cylinder to move the carriage with respect to the supporting surface.

2.-- Stencil printing mechanismcomprising a work supporting surface, -a carriage movable along said surface, stencil printing means on said carriage. an assembly comprising a piston element and a cylinder element, means to connect the assembly to the carriage, means on the assembly to engage the supporting surface, and means to introduce a fluid under pressure into one end of the cylinder to move the carriage with respect to the supporting surface and into the other end of the cylinder to move the said engaging means with respect to the supporting surface.

3. Stencil printing mechanism comprising a work supporting surface, a carriage movable along said surface, stencil printing means on said carriage, an assembly comprising a piston element and a cylinder element, means to connect the assembly to the carriage, means on the assembly to engage the supporting surface, means to lock the carriage with respect to the supporting surface, and means to introduce a fluid under pressure into one end of the cylinder to move the carriage with respect to the supporting surface and into the other end-of the cylinder to move the said engaging means with respect to the supporting surface while the lock means locks the carriage with respect to the supporting surface.

4. Stencil printing mechanism'comprising a work supporting surface, a carriage movable along said surface, stencil printing means on said carriage, a cylinder on the carriage, a piston and connecting rod in the cylinder, fluid connections on the cylinder tomove the piston in opposite directions, and means on the connecting rod to engage the supporting surface.

5. Stencil printing. mechanism comprising a work supporting surface, a carriage movable along said surface, stencil printing means on said carriage, anassembly comprising a piston element and a cylinder element, means to connect one element of the assembly fixedly to the carriage, a guide on the carriage, means to mount the other assembly element slidably on the guide, and means carried by the guide to engage the supporting surface.

6. Stencil printing mechanism comprising a work supporting surface, a carriage movable along said surface, stencil printing means on said carriage, an assembly comprising a piston element and a cylinder element, means to connect one element of the assembly fixedly to the carriage, a guide on the carriage, means to mount the other assembly element slidably on the guide,

a vertically slidable member on the guide to engage the supporting surface, and means to actuate the vertically slidable member by the said other assembly element.

'1. Stencil printing mechanism comprising a able vertically in the crosshead to move into and v out of engagement with the supporting surface, and a connection between the vertically slidable member and the said other assembly element whereby initial movement of the said other assembly element with respect to the guide effects movement of the vertically slidable element with respect to the crosshead and continued movement of the said other assembly element 'moves the crosshead with respect to the guide.

8. Stencil printing mechanism comprising a I work supporting surface, a carriage movable along said surface, stencil printing means on said carriage. a chain secured to the supporting surface, means on the carriage for engaging links of the chain, and means to move the engaging means with respect to the carriage whereby said chain serves as a means for locating the carriage in desired position.

9. Stencil printing mechanism comprising a work supporting surface, a carriage movable along said surface, stencil printing means on said carriage, a circular pitch chain secured to the supporting surface, means on the carriage for engaging links of the chain, and means to move the engaging means with respect to the carriage whereby said chain serves as a means for locking the carriage in desired position.

10. Stencil printing mechanism comprising a work supporting surface, a stencil frame adapted to support a stencil, means to mount the frame on the supporting surface, a squeegee frame mounted on the stencil frame for movement back and forth across the stencil, squeegee elements, spaced fixed pivot means to mount said elements on the frame, and means to mount the elements on the first means with capacity for yielding movement with respect thereto.

11. Stencil printingmechanism comprising a work supporting surface, a stencil frame adapted to support a stencil, means to mount the frame on the supporting surface. a squeegee frame mounted on the stencil frame for movement back and forth across the stencil, squeegee elements, spaced fixed pivot mountings for said elements on said squeegee frame and means for mounting said elements on said pivot mountings yield- -ably with capacity for independent operating spaced fixed pivot mountings for said elements work on said squeegee frame, means for mounting said elements on said pivot mountings with capacity for independent operating movement, and means ments in at least one direction.

13. Stencil printing mechanism comprising a work supporting surface, a stencil frame adapted to limit pivotal movement of said squeegee elevto support a stencil, means to mount the frame spaced flxed pivot mountings for'said elements on said squeegee frame, means for mounting said element on said pivot mountings withcapacity for independent'operating movement, means ;to

limit pivotal movement of said squeegee elements along said surface. stencil printing means on said carriage, an assembly comprising a piston ,element and a cylinder element, means to connect the assembly to the carriage, means on the assembly to engage the supporting surface, means to introduce a fluid under pressure into the cylinder to move the carriage with respect to the supporting surface, and means to restrict gradually the flow of said fluid at one end of movement of the carriage. v v i i 15. Stencil printing mechanism comprising-a work supporting surface, a carriage movable along said surface, stencil printing means on said carriage, an assembly comprising a piston element and a cylinder element, means to connect the assembly to the carriage, means on the as-. sembly to engage the supporting surface, means to introduce a fluid under pressure into the cyl supporting surface, a carriage movable.

lnder tomove the carriage with respect to the CERTIFICATE or coRRsci-Iou.

, the. cylinder element ,able on the supplementary cylinder on having a plurality of ports communicating with the cylinder element and a port communicating with a fluid system, a control, rod in the supplementary cylinder, and means to actuate the control rod by an element H mechanismcomprising a work supporting surface. a carriage movable along said surface, stencil printing means movable on carriage, separate fluid operated supporting surface, a

means to move the carriage and the stencil, a

source of fluid under pressure, valve mechanism to controlthe flow of fluid from the source to the separate means, and selective mechanism to actuate the valve mechanism.

in at least one direction, and means to urge the 1'1. Stencil printing mechanism comprising a squeegee elements toward the stencil. a work supporting surface, a carriage movable 14. Stencil printing mechanism comprising a along said surface, stencil printing meansmovcarriage, separate fluid operated means to move thecarriage and the stencil, a source of fluid under pressure, valve mechanism to control the flow of fluid from the source to the separate means, and selective mechanism controlled by movements of the carriage and frame to actuate the valve'mechanism.

l8. Stencil printing mechanism comprising a work supporting surface, a carriage movable along said surface, stencil printing means movable on the carriage," parate fluid operated means to move the carriage and the stencil, a

sourceof fluidunder pressure, valve mechanism to .control the flow of fluid from th source to the separate means, electromagnetic mechanism to actuate the-valve mechanism, and means operated by the printing means to control-the electromagnetic mechanism. 1

, i WARDTHOBNE.

August: 15," 191 1,.

a Patent No. 2.555.959,

WARD THORNE.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 5, second column, line l claim 9, forthe word "locking" read locatingpage 6, first column, 'line'lh', claim 13, for "element" read "elements"; and that the said Letters Patent should beread with this correction therein that the same may conform to the record or the case :in the Patent 01'- iice.

- Signed and sealed this 26th day of September, A. D. 191-114.

Leslie Frazer (Seal) Acting Commissioner of Patents.

work on said squeegee frame, means for mounting said elements on said pivot mountings with capacity for independent operating movement, and means ments in at least one direction.

limit pivotal movement of said squeegee elements along said surface. stencil printing means on said carriage, an assembly comprising a piston ,element and a cylinder element, means to connect the assembly to the carriage, means on the assembly to engage the supporting surface, means to introduce a fluid under pressure into the cylinder to move the carriage with respect to the supporting surface, and means to restrict gradually the flow of said fluid at one end of movement of the carriage. v v n i i 15. Stencil printing mechanism comprising-a work supporting surface, a carriage movable along said surface, stencil printing means on said carriage, an assembly comprising a piston element and a cylinder element, means to connect supporting surface, a carriage movable.

, the. cylinder element ,able on the supplementary cylinder on having a plurality of ports the cylinder element and a with a fluid system, a consupportingsurface, a

communicating with port communicating ,trol, rod in the supplementary cylinder, and

means to actuate the control rod by an element means to move the carriage and the stencil, a

18. Stencil printing mechanism comprising a work supporting surface, a carriage movable along said surface, stencil printing means movable on the carriage," parate fluid operated means to move the carriage and the stencil, a

sourceof fluidunder pressure, valve mechanism to .control the flow of fluid from th source to the separate means, electromagnetic mechanism to actuate the-valve mechanism, and means opinder tomove the carriage with respect to the erated by the printing means to control-the electromagnetic mechanism. v

i i i a WARD THOBNE.

CERTIFICATE or coRRsci-Ior. I Patent No. 2,355,939. August1l5," 191 1,.

i WARD moans.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 5, second column, line l claim 9, forthe word "locking" read locatingpage 6, first column, 'line'll claim 13, for "element" read "elements"; and that the said Letters Patent should beread with this correction therein that the same may conform to the record or the case :in the Patent 01'- iice.

- Signed and sealed this 26th day of September, A. D. 19%.

Leslie Frazer (Seal) Acting Commissioner of Patents.