US1843116A - Apparatus for producing screen printing - Google Patents

Description

Feb, 2,. 1932. R. B, ALDcRoFTT ET Al.. 1,8431 16 APPARATUS FOR PRODUCING SCR-EEN PRINTING Filed Feb. 11, 1929 5 Sheets-Sheet l Feb.. 2, 1932. R. B. ALDcRoFT-r ET AL 1,843,116

APPARATUS FOR `PHODUGING SCREEN PRINTING filed Feb. 11. 1929 5 sheets-sheet 2 Feb. 2, 1932.

R. B. ALDCROFTT ET AL APPARATUS FOR PRODUCING SCREEN PRINTING Filed Feb. l1. 1929 5 Sheets-Sheet 5 R. B. ,ALDcRoFT-.r ET AL. 1,843,116

APPARATUS FOR PRODUCING SCREEN PRINTING .Filed Feb.. ll, 1929 5 Sheets-Sheet 4 Feb. 2, 1932.

Feb- 2, 1932. R. B. ALDcRoFTT ET AL 1,843,116

APPARATUS FOR PRODUCING SCREEN PRINTING Filed Feb. ll, 1929 5 Sheets-Sheet 5 w S2 Q o5 N ZZor/zeg.

Patented Feb. 2, 1932 UNITED STATES PATENT OFFICE RICHARD B. ALD-CROFTT AND HERBERT RUBAL, F LOS ANGELES, CALIFORNIA APPARATUS FOR PRODUCING SCREEN PRINTING Application filed February 11, 1929. Serial No. 338,976.

Our invention relates, in a sense, to the the plastic paint to the cardboard, through printing art, yet, specifically, it pertains to the screen stencil, with a squeegee; and sepa more modern field of development in that arates and moves the printed product from art, sometimes known as stencil printing?, the stencil, so that the only manual operascreen printing, or the stencil printing tion necessary is the feeding and removal 55 process. of cards from the machine, as in the case of While it is more particularly a method of any ordinary printing press. stenciling, the term printing has generally Uur apparatus is characterized by its exbeen used to designate the work, primarily treme simplicity, few working parts for the 1.3 because it involves the transferl of impresaccomplishment of the several operations, 60

sions from one medium to another, somewhat and its efficiency in operation. as in printing, and because its most general We fully describe the principles of conand practical application has been in prostruction and operation o our apparatus in ducing posters, display cards, placards and the following specification, reference being the like, in the advertising field. Of course, made therein to the accompanying drawings, 65

it-s field of usefulness need not be so confined. wherein we have illustrated one of our pre- The principal distinctions between the ferred specific embodiments. It is to be printing art, asit is generally known, and understood, however, that in describing this this work-which we will term screen printspecific form of our invention, it is primarily 2o ing for Want of a better nameig that in for the purpose of teaching to those skilled in 70 the latter a transfer medium or stencil is the art the principles involved, and is not inprodueed, by masking out, 0n a, fabric tended as a limitation on the invention, as screen-such as coarse silk or the like-all We reserve to ourselves the right to make those portions outside the margins of the de- SllCh ChangeS-or modifications in form or S3 Sign 0r gure it is desired to reproduce, using structure as will come within the scope of the for this purpose a moisture resistant, im- ClalmS appended hereto.

ff pcrvious material, such as glue or lacquer. In the draWlIlgSI The result is a screen stencil, through which F 1g. l 1s a Side elevation of our apparatus, the printing material is passed in applying it Showing the Several moving parts in their 5f. to the background, usually a comparatively first position, at the Start Of the printing 30 heavy cardboard (which term we will hereoperation; inafter use to designate the surface on which Fig. 2 is a view similar to Fig. 1, showing the impression is made, although, obviously, the several moving parts in their second posiother grounds may be used). Instead of ink, tion, during the printing operation;

a suitable paint, vin paste or plastic form, is Fig. 3 is a view similar to F 1 1, showing 85 used to make the impressions; this being apthe several moving parts in their third posiplied by super osing the stencil screen on tion, during the printing operation, which the cardboard, epositing a suitable quantity position these parts occupy just prior to movof the paint on its surface and passing it ing back to the rst position as illustrated 13 through the screen with a squeegee. in Fig. l;

It is our primary object to produce an ap- Fig. 4 is a top plan view; paratus `for the production of this class of Fig. 5 is a central, longitudmal, vertical Work, which will not only facilitate increased section of the upper portion of the apparatus, production over the old hand method, but taken as indicated by the line 5 5 of Fig. 4;

correspondingly lower the cost. In this con- F ig. 6 is a top plan view, similar to Fig. nection, we have producedl a machine which 4, showing the apparatus with the platen automatically accomplishes the work of movand stencil screen removed; ing the cardboard to position; superposes the Fig. 7 is a transverse vertical section taken screen stencil thereover; moves the cardboard as indicated by the line 7-7 of Fig. 4;

C3 into proper contact with the stencil; applies Fig. 8 is an enlarged fragmentary sectional 1"" view showing the relative positions of the squeegee and stencil screen at the start of the squeegeeing operation; and

Fig. 9 is a fragmentary transverse sectional giewtaken as indicated by theline 9-9 of In connection with the following disclothe screen through which the impression is made; the term cardboard to designate the surface on which the impression is made; and

the term paint to designate the plastic -material used. for making the impression on the cardboard, although it is to be understood that more accurate or appropriate terms may be used by those skilled in-the'art.

Referring now to the drawings, the nu meral 10 designates generally a suitable frame-work. This may consist of a pair of longitudinally extending side rails 11, joined by transverse end members 12, these members I. being supported upon endlegs 13 and intermediate legs 14. Additional side rails 15 are secured to side rails 11, these being likewise joined by one of the transversely extending end rails 12, as shown in Fig. 6. Slde rails 11 and 15 may be formed integrally 1f f desired. The rails 15 extend a little above the top edges of the side rails 11, for a purpose which will hereinafter appear.

Tracks 16 extend parallel with and are secured to the inner faces of side rails 11, in spaced relation thereto. Preferably these are in the form of angle irons, as shown in Fig. 7.

A bed or platen 17, for supporting the cardboard during'the printing operation, 1s supported upon the tracks 16, for movement longitudinally of the frame 10. Non-friction rollers -18 are provided on the under side of the platen for engagement with the flange 19, of tracks 16, as shown in Fig. 7.

` The stencil 20 is suitably supported upon a frame 21, the latter being rigidly secured t'o the top edges 22 of side frame members 15, as by means of screws 23 i (Fig. 8). The iop edges of the side frame members 15 are positioned a little above the top edges of the side l f rame members 11, so that when the stencil screen frame is secured thereto the stencil will normally lie in a plane a short distance vabove the top face 24 of the platen 17, the intent being to permit the platen 17 to be moved beneath the stencil 20 Aand thereafter raised against it, as more fully hereinafter set forth.

A pair o f longitudinally extending rals25 are supported above and parallel with the side rails 15 by members 26. Rails 25 are made vertically adjustable, with reference to the surface of the stencil 20, by means of bolts 27 extending through slots 28 and provided withjwing nuts 29. l Rails25 are also spaced from and extend parallel with the top edge 30 of the stencil screen frame 21, so as to form longitudinally extending slots 31 at each side of the stencil screen.'

Referring now more particularly to Fig. 5, a pair of longitudinally extending, parallel tracks 32 and 33 are supported along the inner faces of the rails 25s Track 32 extends the full length of the rail 25, while track 33 terminates short of the ends of the screen, at each end. These tracks 32 and 33 support, and direct longitudinal reciprocating movement of, the squeegee, generally designated by the numeral 34 (Figs. 4 and 8).

The squeegee 34 may consist of a transversely extending bar 35, to the lower Iedge of whichl a scraper 36 is secured, for engagement with the top surface of the stencil screen 20. The scraper 36 will preferably be formed of a yielding material, such as rubber or the like. Pins 37, secured to the ends ofthe bar 35, carry pivot rollers ,38, which are positioned to ride upon the top faces of tracks 32. Pins 39, likewise secured to the ends of bar 35, carry control rollers 40 which are positioned to engage both the top .and bottom faces of the track 33 during forward and backward movement of the bar 35. Tracks 32 and 33 and rollers 38 and 40 are so spaced that the squeegee 34 is maintained in a forwardly inclined position, both during its forward and rearward movement,

as shown in Figs. 4, 5 and 8. This is to facilitate the squeegee or scraping function during forward movement of the squeegee and when in contact with the top surface of the stencil screen 20. The position of the squeegee, during this forward movement, is shown in Figs. 5 and 8, and its position during rearward movement is illustrated in dotted lines at the left in Fig. 5.

' In'the following description we will refer to any movement of the parts to the left, in the several figures of the drawings, as

.the forward movement, and any movement to the right,l as the rearward movement, whether these be movements of theplaten, squeegee or other parts.

During forward movement of the squeegee 34, control rollers 40 are in engagement with the lower face of track 33, as shown at the right in Fig. 5, and as shown in Fig. 9. As the squeegee approaches its extreme forward position control rollers 40 pass underl the yielding deflector 41, secured to the forward end of track 33. 'Upon subsequent rearward movement of the squeegee, ythe forward end of the deflector 41, which is normally lower than the. axis of control rollers 40, engages the under side of the roller, thereby deflecting it upwardly to the top face of track 33, as shown in dotted lines at the left in Fig. 5, further tilting the plate 35 and lifting the scraper 36 out of engagement with the top surface of the stencil screen.

A transversely extending spreader roller 42, which may be formed of rubber or the like, is supported between brackets 43, secured to the under face of the bar 35. This roller serves as a spreader for evenly distributingI the paint over the top surface of the stencil, just forward of the scraper 36.

. During rearward movement of the squeegee this roller is likewise lifted free of the top face of the stencil 20, as shown in dotted lines at the left in Fig. 5.

The rear end of track 33 is bent slightly upwardly, as at 44, so that upon subsequent forward movement roller` 40 will be deflected into engagement: with the under face of track 33.

Longitudinal reciprocating movement of the platen 17 is effected through the medium of a lever 45. This lever is pivotally mounted at its lower end upon a transversely extending shaft 46, journalled in suitable bearings 47, carried by bottom frame members 48. It is more or, less flexibly and movably connected to the platen 17, by means of a pm 49 extending through a longitudinally extending slot 50; the pin 49 being carried between the lower ends of depending brackets 51, secured to the under side of the platen 17. This form of connection permits swlnging movement of the lever 45, from theV position shown in Fig. 1 to that shown 1n F1g. 3. Lever 45 and brackets 51 are posit1oned vcentrally of the frame 10 to move longitudinally thereof, as shown in Fig. 6.

.Longitudinal reciprocating movement of the squeegee 34 is accomplished by means of a pair of levers 52, pivotally mounted at their lower ends, on each side of the frame 10, upon a transversely extending shaft 53; the latter being suitably journalled 1nv the bottom frame member 48. Levers 52 are joined at their upper ends by means of a transversely extending bar 54, to insure uniform and simultaneous movement. They are operatively connected with the squeegee 34 by means of pins 55, carried by the plate 35,'extending through slots 31 and into longitudinally extending slots 56 in the upper ends of levers 52. This form of connection4 permits swinging movement of the levers 52 from the position shown in Fig. 1 to that shown in Fig. 3.

arm 59 formed at its center, consisting of arms 60 and connecting pin 61; the latter serving as a cam member for engagement with cam surfaces 62, 62a, 62?) and 63 in effecting longitudinal swinging movement of the lever 45. During rotation of the crank arm 59, in the` direction indicated by the arrows in the several figures of the drawings, engagement of the pin 61 with the cam surface 63 will effect movement of the lever 45, from the position shown in Fig. 1 to that shown in Figs. 2 and 3, and engagement with the cam surfaces 62 and 62a will effect movement of this lever from the position shown in Figs. 2 and 3 to that shown in Fig. 1.

A cam wheel 64 is rigidly mounted on the outer end of shaft 57, for operative engagement with the adjacent lever 52, as shown in Figs. 1, 2 and 3. Cam wheel 64 has two different cam elements 65 and 66, the former serving to move lever 52 from the position illustrated in Fig. 3 to that illustrated in Figs. l and 2, and the latter serving to move lever 52 from the position shown in Figs. 1 and 2 to that 'shown in Fig. 3. In moving levers 52 from the position shown in Fig. 3 to that shown in Figs. 1 and 2, cam surface 65a, of the cam element 65, engages a cam surface 67 adjacent the lower end of the adjacent lever 52; and in effecting movement of levers 52 from the position shown in Figs. 1 and 2 to that shown in Fig. 3, a pin 68, carried by the cam element 66, engages in a longitudinally extending cam slot 69, carried by the adjacent lever 52.

As the platen 17 is moved, by lever 45, b eneath the stencil 20, being supported upon tracks 16, its top surface 24 is normally spaced a little below the' bottom face of the stencil screen. After moving it to proper position, it is then necessary to raise it, to bring the cardboard carried upon its surface into close contact with the stencil and to rigidly support it during the squeegeeing operation of passing the paint through the stencil screen, after which it is necessary to lower the platen and remove it from beneath the stencil, so the printed product may be removed and other cardboard supplied to repeat the operation. In effecting both the upward and downward movement of the platen 17 it is necessary that these movements be truly vertical and not in the least lateral, in order to avoid smearing the paint deposited thereon. In this connection, it is to be kept in mind that the plastic material utilized in making the impressions is thicker than the D usual printers ink, and, therefore, its applistencil 20 it passes between side frame mem- 13 bers 15,'which carry vertical guides 15a for it when raised from the tracks 16, into engage-` lmedium of toggle links 72 and 73 pivotally joined at 74 and 75; the toggle links 73 being supported at their lower ends upon block 76 and pivotally connected thereto at 77. Movement of the links 73 to the right, in Fi 1, will efect, through the medium of lin s 72, vertical movement off blocks 70, as

illustrated in Figs.l 2 and 3. Four of the bars 70 are provided, as shown in Fig. 6, for

engagement with the under face of the platen 17 at each corner, thereby insuring even and uniform movement. Links 7 2and 73 are operativel connected in pairs, at each` side of the mac ine, by means of connecting rods7 8 (Fig. 6), and the endmost pair of links 73 are also operatively connected by a transversely extending bar 79. Connecting rods 78 are pivotally connected with links 73 at 80, to permit free swinging movement.

Normally the blocks and links 72 and 73 are in the position shown in Fig. 1, which is the position they occupy when the platen 17 is moved to position beneath the stencil 20 and before upward movement is effected. Upward movement of blocks 70 is accomplished by means of pin 61, of crank arm 59, engaging the end 81 of a beam 82, at a certaln stage of its rotation, thereby efecting movement of the beam to the right in Fig. 1.. Beam 82, which is positioned centrally of the frame 10, as shown in Fig. 6, is Aoperatively connected with toggle links 73 by means of bars 83, 84 and 79, and the connecting rods 78. Thel bar 83 is pivotally connected at 85 with the transverse frame member 12 andits lower end engages in a recess 86 in the upper edge of the beam 82.

Beam 82 is normally in the position illustrated in Fig. 1. A downwardly extending projection 87, on the bottom edge of beam 82, normally rests in a notch in the upper edge of a iixed block 88. lProjection 87 forms a shoulder 89 adapted to engage one face of the block 88 (the right face in Fig. 1) when the beam 82 is moved rearwardly (to the right in Fig. 1) `by engagement of crank arm pin 61 with the beam end 81. When so moved rearwardly beam 82fdro s b its own 60 weight and shoulder 89 hol s t e beam 'against movement in the opposite direction. This movement of the beam 82 (to theright in Fig. 1) eliects simultaneous upward movement of the blocks 70, and consequent lifting,

of the platen 17 into engagement with the bottom face of the stencil 20, through the bars 83, 84 and 79, toggle links 73, connecting rods 78 and toggle links 72, these parts assuming the positions illustrated in Figs. 2 andV 3. Cushioning of the rearward movement of the beam 82 and the upward lift of the platen 17 may be accomplished through the medium of a shock absorber 90 connected between the beam end 91 and a transversely extending frame member 92. This shock absorber may be' of any of the well known types.

As'the platen is supported in the positions illustrated in Figs. 2, 3 and 5 by the toggle connections 72 and 73 and so held by engagement of the shoulder 89 with block 88,`the platen is lowered and the supporting elements returned to the position illustrated in Fig. 1, by raising'the inner end of beam 82 and releasing shoulder 89 from engagement with block 88. This is accomplished by-continued upward movement of the crank arm 59 (in the direction indicated by the arrows) and engagement of the pin 61 with the free end 93 of a bar 94, as shown in Fig. 3. Bar 94 is pivotally mounted upon the frame 10, as at 95, and is operatively connected with beam 82 by means of a connecting rod 96, so that upward movement of-bar 94 will lift beam 82 suicient for the shoulder 89 to pass over the upper edge of block 88. The weight of the 'platen 17 is suiicient to cause it to drop back u on the tracks 16 and to move the blocks 0, toggle links 72 and 73 and the other connecting parts, from the positions l shown in Figs. 2 and 3 to thatfshown in Fig. 1.

Cushioning of the platen 17 at the end of its forward and rearward movements is effected by brackets 51 engaging transversely extending bars 97. Bars 97 are interconnected by means of longitudinally extendin bars 98 and are slidably supported upon anges 99, of tracks 16, through the-medium of shoes 100. Shock absorbers 101 are provided intermediate the bars 97 and end frame members 12, which may be of any of the wellknown forms. Those here shown consist of the usual air cylinder type.

In the operation of the machine, assuming the parts to be in the positions illustrated in Fig. 1, which is the first position at the start of the printing operation,.and assuming the crank arm 59 to be rotated in the direction indicated by the arrows in Figs. 1, 2 and 3, the several movements are as follows: A

'sheet of cardboard is first placed upon the in Fig. 1 to that shown in Fig. 2, which is the second position. Just as the pin 6l, of crank arm 59, passes from engagement with the cam surface 63, it strikes the end 81 of beam 82, throwing it rearwardly (to the right in Fig. 1), causing it to drop down, of its own weight, and shoulder 89 to engage the rearward face of the block 88, which holds the beam in such rearward position. This rearward movement of beam 82, through the medium of bars 83, 84 and 79 and connecting rods 78 causes movement of the toggle links 73 (to the right in Fig. 1) and a consequent upward movement of toggle links 72 and blocks 70. As the platen 17 has been moved to its full rearward position before pin 61 strikes end 81 of beam 82, upward movement of blocks 70 will cause them to engage the under face of platen 17, carrying it upwardly so the cardboard carried thereon is in slight pressural engagement with the bottom surface of the stencil screen 20. During this time levers 52 have been in the positions illustrated in Figs. 1 and 2, holding the lsqueegee 34 at one end of the stencil 20, as illustrated in Fig. 4. Continued rotation of shaft 57 carries the cam element 66 forwardly and immediately after pin 61 has engaged beam 82 and moved it rearwardly, with a consequent raising of the platen 17 to printing position, as shown in Fig. 2, pin 68 engages in cam slot 69 and further rotation of shaft 57 effects movement of levers 52 from the position shown in Fig. 1 to that shown in Fig. 2. The start of this movement is shown in Fig. 2 and its finish is shown in Fig. 3, and in traveling between these two positions the squeegee 34 is carried across the stencil screen 20, with scraper 36 and spreader-roller 42 in contact with its top surface. During this movement roller 42 evenly distributes the paint while the scraper 36 forces it through the screen over the areas not rendered impervious. During movement of levers 52, from the position shown in Fig. 2 to that shown in Fig. 3, lever 45 remains in its second position, as shownin Fig. 3, the cam roller passing around the cam surface 62 to engage cam surface 62a, as shown in Fig. 3. Just before engaging the cam'surface 62a, pin 61 has engaged the free end 93 of the bar 94, raising the beam 82 so shoulder 89 is freed from block 88. The weight of the platen 17 then causes it to drop and force bars 70, toggle links 72 and 73 down to the positions shown in Fig. 1, and, through the medium of connecting rods` 78, bars 79, 84 and 83 causes a movement of the beam 82 from the position shown in Fig. 3 to that shown in Fig. 1.

As the levers 52 near the position shown in Fig. 3, control rollers 40, of the squeegee 34, pass under the flexible deflector 41, so that upon movement in the opposite direction these deflectors will pass under control rollers 40 and deflect them to the top surface of track 33, thus raising spreader-roller 42 and scraper 36 from engagement with the top surface of the stencil screen.

Continued rotation of the crank arm 59 moves the lever 45 from the position illustrated in Fig. 3 back to its first position, as shown in Fig. 1, moving the platen 17 out from under the stencil screen and back to its first position. In this position the printed card is removed from the platen and a new one substituted. During this movement pin 61 has been in engagement with the cam surfaces 62 and 62h of lever 45.

While the crank arm 59 is moving the lever '45 from the position shown in Fig. 3 to that shown in Fig. 1, the cam clement 65 is moving toward lever 52 and moving the cam surface 65a into engagement with the surface 67. By the time the platen 17 is returned to its first position, as shown in Fig. 1, levers 52, carrying the squeegee 34, as shown in dotted lines in Fig. 5, have been moved, by the cam member 65, from the position shown in Fig. 3 to that shown in Fig. 1, thus returning the squeegec to its first position.

As shaft 57 is continuously rotated, the above cycle of operations is completed in connection with each printing operation; the printed card being removed from the platen, and a new one, to be printed, to be substituted therefor each time the platen 17 reaches its forward or first position, as shown in Fig. 1.

Paint may be supplied to the upper surface of the stencil screen in any suitable manner, either byhand or by automatic feed. Having described our invention, we claim:

1. In a stencil printer, the combination of a frame; a stencil supported by the framel a squeegee reciprocating with respect to t e stencil; and means associated with the frame and squeegee, including a track and a controlroller in cti-operation, adapted to effect contact between the squeegee and the stencil during one movement of the reciprocation and to effect spaced relation during the return movement.

2. In a stencil printer, the combination of a frame; a stencil supported by the fame; a squeegee reciprocating with respect to the stencil; a spreader-roller attached to the squeeg'ee; and means associated with the frame and squeegee, including a track and a control-roller in co-operation, adapted to effect Contact between the stencil and both the squeegee and the spreader-roller during one movement of the reciprocation and to effect spaced relation during the return movement.

3. In a stencil printer, the combination of a frame; a stencil supported by the frame; a squeegee reciprocating with respect to the stencil; a track associated with the frame; and a control-roller associated with the squeegee, said track and control-roller being adapted to co-operate to eect contact between the squeegee and the stencil during one movement of the reciprocation and to eil'ect spaced relation during the return movement.

4. In a stencil printer, the combination of a frame; a stencil supported by the frame; a squeegee reciprocating with respect .to the stencil; a spreader-roller assoclated with the squeegee; a track associated with the frame;

and a control-roller associated with the squeegee, said track and said control-rollerI being adapted to co-operate to effect contact between the stencil and both the squeegee and spreaderroller during one movement of the reciprocation and to effect spaced relatlon during the return movement.

5. In a stencil printer, the combination of a frame; a stencil supported by the frame; a squeegeev associated with the stencil; means to reclprocate the squeegee; a track mounted on thea frame substantially parallel with the spreader-roller associated with the squeegee;

meansto reciprocate the squeegee and spreader-roller; a 4track mounted on thel Aframer substantially control-rol er associated with the squeegee .engaging the lower surface of the track' during one movement of the reciprocation there-- 40 by applying the squeegee and spreader-roller to t e stencil, and engaging theupper surface 'of the track during the return-molement of the reciprocation thereb maintaining both the squeegee and sprea er-roller in 45 spaced relation to the stencil.

7. Inf'a stencil printer, the combination of a frame; a stencl a squeegee associated wlth the stencil; means to reciprocate the squeegee.; a track mounted on the frame substantially parallel with the stencil, said track having a delector at each end oppositely disposed; and a controlroller associated with thesqueegee engaging the lower surface of the track during one movement of 'the reciprocation thereby ap-l plying` the squeegee to the stencil, and engagmg the upper surface of the track during the return movement of the reciprocation thereby maintaining the squeegee 1n spaced relation to the stencil. 1

8. In a vstencil rinter, the combination -of a frame; a stencil supported by theframe; a squeegee associated with the stencil; -a spreader-roller associated with the squeegee;

35 means to reciprocate the squeegee and spreadarallel with the stencil; and av supported by the frame; n

er-roller; a track mounted on the frame substantially parallel with the stencil, said track Having a deliector at each end oppositely disposed; and a control-roller associated with the squeegee engaging the lower surface of the track during one movement of the reciprocation thereby applying the squeegee and spreader-roller to the stencil, and engaging the upper surface of the track during the return movement of the reciprocation thereby maintaining both the squeegee and spreader-roller in spaced relation to the stencil. 'r

9. In a stencil printer, the combination of a frame; a stencil supported by the frame; a. squeegee associated with the stencil; means to reciprocate the squeegee; a track mounted on the frame substantially parallel with the stencil, said track having one end turned up and the opposite end turned down; and a control-roller associated with the squeegee engaging the lower surface of the' track durmg one movement of the reciprocation thereby applying the squeegee to the stencil, and engaging the upper surface of the track durlng the return movement of the reciprocation thereby maintaining the squeegee 1n spaced relation to the stencil.

10. In a stencil printer, the combination of a frame; a stencil supported by the frame; a squeegee associated with theM stencil; a spreader-roller associated with the squeegee;

means to reciprocate the squeegee and spreader-roller; a track mounted on the frame substantially parallel with the stencil,- said track having one end turned up and the opposite end turned dwn; and a control-roller associated with the squeegee engaging the lower surface of the track during one movement of the reciprocation thereby applying the squeegee and spreader-roller to the stencil, and engaging the upper surface oi the track during the return movement of the reciprocation thereby maintaining both the squeegee and the spreader-roller 4in spaced relation to the stencil.`

11. In a stencil printer, the combination of a frame; a stencil supported .by the frame; a

4squeegee associated with the stencil; means to reciprocate the squeegee; two tracks sub'- stantially parallel, one above the other, mounted to the Vframe; a pivot-roller associated with the squeegee reciprocating along one of the tracks; and a control-roller associated with the squeegee co-a'ctin'g with the second track thereby positioning the squeegee during one movement offthe reciprocation to an angle of contact with the stencil, and

at an angle of spaced relation during the returnmovement. f

12. In a stencil printer, the combination of a frame; a stencil supported by the frame; a squeegee associated with'y the stencil having a reader-roller associated therewith; power riven means to reciprocate the squeegee;

two tracks substantially parallel, one above the other, mounted to the frame; a pivotroller associated with the squeegee reciproeating along one of the tracks; and a controlroller associated with the squeegee co-acting with the second track thereby positioning the squeegee during one movement of the reciprocation at an angle of contact with the stencil, and at an angle of spaced relation during the return movement.

13. In a stencil printer, the combination of a frame; a stencil supported by the frame; a squeegee associated with the stencil; power` driven means adapted to reciprocate the squeegee; two tracks' substantially parallel,

one above the other, mounted to the frame; a pivot-roller associated with the squeegee reciprocating along one of the tracks; and a control-roller associated with-the squeegee engaging the lower surface of the secondA track during one movement of the reciprocation thereby maintaining the squeegee at an angle of contact with the stencil, and engagingthe upper surface of said second track during the opposite movement thereby maintaining the squeegee at an angle of spaced relation to the stencil.

14. In a stencil printer, the combination of a frame; a stencil supported by the frame; a squeegee associated with the stencil having a spreader-roller associated therewith; power driven means adapted to reciprocate the squeegee; two tracks substantially parallel, one above the other, mounted to the frame; a pivot-roller associated with. the squeegee reciprocating along one of the tracks; and a control-roller associated with the squeegee engaging the lower surface of the second track during one movement of the reciprocationthereby maintaining the squeesqueegee at an angle of spaced relation to the stencil.

16. In a stencil printer, the combination of a frame; a stencil supported by the frame; af squeegee associated with the stencil having a spreader-roller associated therewith; power drlven means` adapted to reciprocate the squeegee relative to the stencil; a track mounted on the frame substantially parallel with the stencil; a lower and shorter track mounted on the frame substantially parallel with the stencil, said lower track having one end turned up and one end turned down; a pivot-roller associated with the squeegee reciprocating along the upper track; a controlroller associated with the squeegee engaging the lower surface of the second track during one movement of the reciprocation thereby l maintaining the squeegee at an angle of contact with the stencil, and engaging the upper surface of said second track duringfthe op- A posite movement thereby maintaining the squeegee at an angle of spaced relation to the stencil.

In witness that We claim the foregoing we have hereunto subscribed our names this 4th day of February, 1929.

RICHARD B. ALDCROFTT. HERBERT RUBAL.

gee at an angle of contact with the stencil, and

engaging the upper surface of said second track during the opposite movement thereby maintaining the squeegee at an angle of spaced relation tothe stencil.

15. I-n a stencil printer, thecombination of a frame; a stencil supported by the frame; a squeegee associated with the stencil power driven means adapted to' reciprocate the squeegee relative to the stencil; a track mounted on the frame substantially parallel with the stencil; a lower and shorter track mounted on the frame substantially parallel with the stencil, said lower track having one end turned up and one end turned down; a

. pivot-roller associated with the squeegee reciprocating along the upper track; a controlroller associated with the squeegee engaging the lower surface of the second track during one movement of the reciprocation thereby maintaining the squeegee at an angle of contact with the stencil, and engaging the upper surface of said second trackiduring the lopposite movement thereby maintaining the

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