US2202799A

US2202799A - Stenciling apparatus

Info

Publication number: US2202799A
Application number: US244430A
Authority: US
Inventors: Albert S Jackson; Clarence A Heyne
Original assignee: Owens Illinois Glass Co
Current assignee: OI Glass Inc
Priority date: 1938-12-07
Filing date: 1938-12-07
Publication date: 1940-05-28
Anticipated expiration: 1957-05-28

Description

May 28, 1940- A. s. JAcKsoN ET AL v 2,202,799 sTENcILING APPARATUS Filed Dec. 7, 1938 7 `Sheets-Sheet l May 28, 1940 A. s. JACKSON Er Al. 2,202,799

s'rENcILING APPARATUS Filved Deo.

7, 1938 7 Sheets-Sheet 2 May 28, 1940. A. s. JACKSON ET AL STENCILING APPARATUS Filed Dec. .7, 1938 7 Sheets-Sheet 3 May 28, 1940.

A. s. JACKSON ET AL STENCILINGr APPARATUS Filed-Dec. 7, 1938 '7 Sheets-Sheet 4 May 28 1940- A. SQ JACKSON Er A1. 2,202,799

STFNCILING APPARATUS Filed Dec. 7, 1938 7 Sheets-Sheet 5 ATTO May 23, 1940- A. s. JAcKsoN ET A1.v

sTENcILING APPARATUs Filed Dec. '7, 1938 7 Sheets-Sheet 6 INVENPORS f1.5. UqcKso/vm BY LL/Yawn:

A TTO My 2s, 1940.

A. s. JACKSON Er AL s'rENcILING AFPARATUS 7 Sheets-Sheet 7 Filed Dec. 7, 1938 'Patented PATENT ori-lcs 13 claims. (ci. rc1-124) *uflsuTl-:D- STATES The improved stenciling apparatus comprising the presentinvention is primarily adapted for use in4 applying a vitreous enamel composition mechanism by means vor paint to the tapered shoulder Aportions of articles of glassware such as bottles or jars in the lettering'or decorating thereof by a stenciling process. f The principal object of the invention is to provide a -stenciling apparatus which will generally simplify the setting up operations for bottles of different sizes or for bottles havingtapered shoulder portions that differ in slope and which will also generally simplify and improve the operation of applying the vitreous enamel composition to such articles, thus improving the quantity of the work performed as well as the quality anduniformity thereof and also lessening the labor or skill otherwise required in performing the same type of stenciling operations. I

The Ainventin is embodied in an apparatus of the type employing a reciprocable stencil screen capableof oscillatory movement .relative to the article undergoing decoration together with a relatively stationary squeegee by means of which the enamel compositionv is forced through the screen and onto the surface of the article undergoingM decoration. A further object of the invention is to provide an apparatus of the character referred to in'which there is incorporated an improved means for varying the extent lor amplitude of screen oscillation to accommodate-bottles having varying characteristics.

Another object of the invention is to provide an improved squeegee supporting assembly in which the squeegee is adjustable relative to the stencil screen and from which it is readily ref along the line 22-22 of Fig. 19.

movable.

Other objects of the invention, not at this time enumerated, will become readily apparent as the nature of the invention-is better understood.

In the accompanying drawings:

Fig. l is a side elevational view of a stenciling apparatus constructed in accordance with the principles of the present invention;

Fig. 2 is an enlarged detailedV side elevational View, partly in section, of the apparatus proper; Fig. 3 is an enlarged vertical sectional view taken through a. chuck supporting .and driving mechanism employed in connection with the present invention; Fig. 4 is a front ratllS;

Fig. 5 is a top plan view thereof; Fig. 6 is a sectional view taken substantially along the line 6-6 of Fig. 2; l v

Fig. 7 is a side elevational view illustrating the of which the bottle supporting instrumentaiities may be adjusted:

elevational view of the appa- Fig. 8 is a sectional View) taken substantially along'the line 8-8 of Fig. 2; I Fig. 9 isa sectional view taken substantially along the line 9-9 ofI Fig. 3;

Fig. 10 is a sectional view taken substantially along the line IIJ-l0 of Fig. 9;

Fig. l1 is a sectional View taken substantially `along the line II-II of Fig. 9',

Fig. 12 isf'a sectional view taken substantially along the line I2- I2 of Fig. 1;

Fig. 13 is a fragmentary side elevational View,

partlyA in section, of theinstrumentalities shown in Fig. 12;

Fig. 14 is a sectional view taken substantially along the line H `|4 of Fig. 12;

i Fig. 15 is a fragmentary end elevational view of the mechanism by means ofwhich the ystencil screen assembly is raised and lowered;

Fig. 16 is a diagrammatic View illustrating the pneumatic control mechanism for the stenciling apparatus when the stencil l.screen is in one extreme position thereof;

Fig. 1'7 is a' diagrammatic view similar to Fig. 16 with the screen in its other extreme position;' y

Fig. 18 is an end elevational View of a control valve employed in connection with the invention;

Fig. 19 is a vertical sectional view taken. through the valve of Fig. 18;

Fig. 20 is a fragmentary side elevational view, partly in section y,of an actuating valve employed in connection with the invention;

Fig. 21 is another fragmentary elevational View of theactuating valve showing the valve plunger in a different position; and

`Fig. 22 is a sectional View taken substantially BRIEF DESCRIPTION including a table portion 3| upon which are mounted the various decorating instrumentalities proper. A tiltable Abottle supporting assembly 32, also mounted on the table `portion 3|, includes a base chuck 33 and a head chuck 34 adapted to support therebetween a bottle B or other article to be decorated. Means is provided for adjust- `ing the inclination of the bottle supporting assembly 32 and for clamping the same in any de-A sired adjusted position in order that the tapered shoulder portion of the bottle B may be broughtinto tangential rolling line contact with the underneath surface of a horizontally oscillatable stenbil screen S forming a part of a stencil screen assembly 35.

The head chuck\34 is movable toward and away from the base chuck 33, such movement \be ing effected by a piston notor 36 whichl is actuated by a control valve 31 (Fig. 4). Upon initial depression of a foot treadle 38 the control valve 31 is actuated and the head chuck 34 is moved toward the base chuck 33 to clamp the bottle B between the two chucks during decora.- tion thereof. Further depression of the foot treadle causes a control valve 39 to be actuated to operate a piston motor 40 (Fig. 1) Vand impart osc atory movement in one direction to the sten il screen S while at the same time the base chuck 33 is rotated so that the bottle B will make tangential rolling line contact with the moving Screen. During oscillation of kthe screen S, a squeegee S forming part of a squeegee assembly 4| is maintained in contact with the screen along the line of contact between the screen and bottle. Upon completion of the decorating stroke, means is provided for elevating the squeegee out of contact with the screen to clear the pool of decorating enamel placed thereon. Upon release of the treadle, the head chuck 34 is movableaway from the base chuck 33 to release the decorated bottle.

THE BofrrLE SUPPORTING ASSEMBLY (a) The head chuck and base chuck mountings Referring now to Figs. 1, 2, 6 and 7, the bottle supporting assembly comprises an elongated support which is clamped as at 46 for axial adjustment on a tiltable cradle 41, the latter being pivoted as at 48 (Figs. 6 and 7) `to a standard 43 bolted as at 50 to the table portion 3| of the carrier 30. A sector plate 5| depends from the cradle 41 and the lower edge 52 thereof cooperates with a clamping member 53 for clamping the plate 5| and consequently the cradle 41 in any desired adjusted position.

'I'he head chuck 34 is carried at the outer end of a piston rod 55, the piston 56 for which is disposed in a cylinder 51 clamped as at 58 for axial adjustment on the support 45 adjacent one end thereof. A coil spring 53 normally urges the piston rod 55 to a retracted position. The other end of the support 45 terminates in a plate 60 (see also Fig. 3) to which there is secured a frame 3| having a cover plate E2 associated therewith. 'Ihe base chuck 33 is provided Vwith a shank 63 which is rotatably journaled in the plate SI1 and from which there extends a stub shaft 3,4. A.

" sprocket 35 is mounted `on and keyed' to the stub shaftA 34 and forms one element of a train of driving mechanism which will be described presently and by means of which the base chuck is periodically rotated in opposite' directions inl order that the bottle B sup rted between the head and base chucks 34 and 33 respectively may make tangential rolling line contact with the oscillatable stencil screen S.

It is apparent that by virtue of the clamping means 33 thehead'chuck 34 may be adjusted toward and away from the base chuck 33 in order to accommodate bottles of different lengths. Also, the positions of the base and head chucks 33 and 34maybeadjstedinunisonaxiallyin order to bring the shoulder portions of the bottles B into accurate register with the sweep of the decorating portions of the screen S to Droperly locate the decorations on the bottles.

(b) The 'control valve for the head chuck In order to periodically move the head chuck 33 from its retracted position against the action ofthespring 33andthus clampa bottleBbetween the two chucks. means-is provided'or periodically supplying air under pressure to the cylinder31 toimpeltbepistonthereinfor- Ward. Toward this end, the interior of the cylinder 51 communicates through a flexible conduit 66 with th'e control valve 31 (Fig. 4) through which compressed air is supplied from a compressed air tank 61 suitably mounted on the carrier 30 beneath the table portion 3|.

v4The control valve 31 (Figs. 4, 1'7. 20 and 21) comprises a cylinderl which depends from the table portion 3| and' which is formed with aligned ports 1| and 12 therein and an exhaust port 13. The port 1| communicates with the conduit 6G while the port 12 communicates through a conduit 14 with the compressed air tank 61. A piston valve member 15 disposed within the cylinder 10 is provided with an annular groove 16 and communicating

longitudinal grooves

11 and 18 respectively, which grooves are adapted, to establish communication between the exhaust port 13 and port 1| when the valve member 15 is extended as shown in Fig. 20 and. to establish communication between the ports 1| and 12 when the valve member 'is elevated as shown in Fig. 2l.

The valve member 15 is connected through a thrust link (Fig. 4) to a lever 8| secured to a rock shaft 82 supported in brackets 83 suspended from the carrier 30. The rock shaft is connected through levers 84 to the-A foot treadle 38 and is adapted to be actuated thereby. A spring 85 serves to elevate thefoot treadle 38 and maintain the valve 31 in the position shown in Fig. 2O wherein the cylinder 51 is exhausted to the atmosphere and thehead chuck 34 is in its retracted position.

It is apparent that upon initial depression of the treadle 38, the valve 31, through the medium of the rock shaft 32,1ever 8| and link 30. is moved to the position shown in Fig. 2l and air is supplied to the cylinder 51 tonove the head chuck 34 to its bottle engaging position.

(c) Base chuck rotating instrumentazities Referring now to Figs. 2 and 3 wherein the train of mechanism previously mentioned for rotating the base chuck 33 in opposite directions is shown, a bracket 93 suspended from the support 43 serves torotatably support one end of an elongated spline shaft 9|, the other end of which is rotatably ypiournalled in the plate 33 and carries a sprocket 32. A chain 33 passing over the sprockets 32 and 63, having a tightening mechanism 34 associated therewith, serves to drive the base chuck 33 from the shaft 3|.

The shaft 3| is adapted to be rotated in the opposite direction as periodically and toward this end a superstructure 33 secured to the table portion 3| of the carrier 33 serves to slidably support a horizontally l/reciprocable lrack 33 which meshes with ,a gear/ 91 mounted on a shaft 33 (see also Fig. 6) rotatably journalled in the superstructure 33. A pair of bevel gears 33 and |33 connect the shafts 33 and 3|. The rack 33 is adjustably secured as at |3| to a piston rod |33 and is axially adjustable with respect to the latter, the'adjustable connection being provided in order to compensate for any arbitrary adjustment of the angularityof the article supporting assembly 32 to insure that the rack 33 will not become disengaged from the gear 31 during nor'- mal reciprocation of the former. A, piston |33 mounted on the rod |32 is slidably disposed in a main operating cylinder |34 secured in the superstructure 33 and the piston is adapted to be reciprocated by the admission of air throughthecontrolvalvealternntelytothers vvscrew |50 and may be clamped in any desired adopposite .sides of the cylinder |04 in a manner "subsequently to be described.

A pointer |05 (Figs. 2 and 3) secured to Athe frame 6| overlies the bottle B when supported in the

chucks

33 and 34 and facilitates insertion of the bottle in the apparatus properly oriented for application of theA decoration to the shoulder portions I'thereof on opposite sides of the usual moldseams occurring on the bottle.

THE STENCIIL ScaEEN ASSEMBLY (a) The stencil screen mouniings Referring now to Figs. 1 and 2, a hollow standard ||0 extends upwardly from the base portion of the superstructure 95 and has secured thereto adjacent the top thereof a hollow horizontal arm which in part overlies the bottle supporting assembly 32. The forward end of the arm-I II is provided with a web I|2 and a removable cover plate ||3 providing a gear box or chamber ||4. Extending vertically through the gear box ||4 and journalled in bearings I I5 therein is a tubular sleeve ||6, the lower end of which depends from the arm I'II and has secured thereto an inverted U-shaped frame ||1, the legs ||8 of which have slidably mounted therein vertically adjustable rack bars I I9 (Fig. 4) that mesh with pinions |20 mounted on a shaft I2I extending across the frame. An adjusting screw |22 controls the elevation of the rack bars ||9 whilel a tightening screw I 23 locks the shaft I2I and consequently the rock bars I I9 in any desired adjusted position. A stencil screen frame |24 is suspended from the lower ends of the rack`bars I9 and, upon manipulation of the screws |22 and |23 is adjustable to the proper height for cooperation ofthe screen S supported thereby with the tapered shoulder portion of the bottle B positioned between the chucks- 33 and 34.

(li) Instrumentalities for reciprocating the stencil screen `a`guide I3| provided between the table portion 3| of the carrier 30 and the superstructure 95.

The rack bar |30 meshes with a pinion |32 mounted on a vertical shaft |33 disposed within the standard IIO. A bevel gear |34 at the upper end of the shaft |33 meshes with a similar bevel 'gear |35 mounted on the inner end of a shaft |36 mounted within the horizontal arm The outer end of the shaft |36 carries a bevel gear |31 whichimeshes with a bevel gear |38 mounted on the tubular sleeve I6 within the gear box I4. Thus it will be seen that reciprocation of the rack bar |30 causes oscillation of the entire stencil screen. assembly 35 about the axis of the tubular sleeve ||6 and the amplitude of such oscillation is dependent upon the extent of reciprocation of the rack bar |30.

Thus it will be seen that the nearer the position of the b1oci:,|41 to the axis of the pin |45, the

smaller will be the extent of reciprocation of the rack |32 when the beam |44 is oscillated uniformly. A pointer |53 (Figs. 9 and 10) is secured to the block |41 and overlies a scale |54 on the beam |44 and facilitates proper adjustment of the parts for varying the amplitude of oscillation of the block |41, and consequently for Varying the am- THE SQUEEeEn ASSEMBLY I y (a) The squeegee assembly mountings y Still referring to Fig. 2, a bracket |60 depends from the horizontal arm 'and carries at its lower end a horizontal rock shaft |6I on which the squeegee assembly 4| per se is pivoted. The squeegee assembly' 4| includes a slotted tubular4 member |62 or support having a bifurcated portion |63 pivoted to the rock shaft `|6I. A clamp |64 or squeegee holder support (see also Figs. 13 and `14) surrounds the member |62 andis adapted to be adjustably clamped in any desired axial position thereon by means of a clamping bolt |65. The squeegee holder support |64 is formed with a vertically extending recess |66 or guideway thereinwhich is covered by a plate |61.A A squeegee fholder |68 is vertically adjustable in the recess |66 by means of an adjusting screw |69, a clamping nut |59 being provided for locking the holder in any desired adjusted position. The lower end squeegee S is pivotally supported between' the `furcations of the holder by means of a spring of the holder |68 is bifurcated as at |10 andthe pressed pin |1| which extends through a hole |12 formed in the squeegee S. The pin |1| is retractable from the hole |12 .to permit the squeegee S to be readily removed from the holder and to permit substitution ci squeegees.

(b) Mechanism for elevating the squeegee at the end of each stroke of the stencil screen Returning to Fig. 3, a spring pressed plunger |15 extends through the tubular member |62 and is provided with a head |16 which is selectively receivable in one of a pair of notches |11 and .|18 provided in a lifting member |19 pivoted |6|. A rod |8| extends through the sleeve ||6 and is radjustably secured as at |82 to one end of alever |83 which is pivoted as at |84 medially of its ends to a -l`lower end of the link |86 is connected to a lever |88 which is pivoted medially of its ends to an extension |89 formed on a bracket |90 secured to the superstructure 95. A coil spring |94 normally urges the link |86 upwardly to tilt the lever |83 in such a manner that a downward impetus is applied to the squeegee S. The other end of the lever |88 carries a cam roller |9| 'I'he other which bears against a` reciprocable runway |92 or slide member which is formedas an extension of the rack bar 96; A pair of wedge-like mem-7 bers |93 or cams is adapted .upon reciprocation of the rack bar 86 to pass under the cam roller |9| as the stencil screen S approaches the limit of itsV stroke in either direction tol actuate the train of mechanism just described leading from the roller ISI to thesqueegee vi5 lto elevate the latteras the stencil screen'S moves to its limiting positions.

be tilted rupwardly/and the plunger |15 released to allow the head \|16 to enter the notch |18 and maintain thef assembly in lsuch a position that the stroke 0f the. link |86 vis of insufficient amplitude to cause the squeegee to contact the screen.

THE CONTROL v'VALVE Foa THE MAIN GPERATING CYLINDER Referring now to Figs. 16, 17, 18, 19 and 22, the control valve 31` is connected by means of a link 200 to a lever 20| (Fig. 4) mounted on the rock shaft 82 and thus the valve 31 is operable from the foot treadle 38.

Conduits

203 and 204 connect' the valve 31 with opposite ends of the r cylinder |04 while a conduit 205 leading from the compressed air tank 61 establishes communication through branch conduits 206 and'201 with the valve 31.

The valve 31 is substantially identical in construction with the control valve for the main operating cylinder of the structure shown` and described in detail in a, copending application for United States Letters P'tent filed by J. `E.

McLaughlin and A. S.'Jac 231,888,1led September`27, 1938, for Stenciling apparatus, and reference may be had to said application for a full disclosure thereof. It is deemed suiiicient `to state that the conduits 203,

204, 206 and 201 are so connected'to the valve 31 that' upon depression of` the.y foot treadle 38.

slightly beyond an initial movemenathereof, the

valve becomes operative to drive the piston |03 in the main operating cylinder |04 in one direction by admitting compressed air to one end of 4the cylinder. Upon the next succeeding operation of the treadle mechanism, the valve 31 be'- comes operative to drive the piston in the opposite direction. In this manner the stencil screen and bottle are actuated in unison in the manner f tive to the lifting member, a squeegee holder sepreviously described so that they make' tangential Y horizontally reciprocable on, Serial Number or other articles. In the appended claims, the `term,reciprocation" is intended to'mean a toand-fro motion. of the stencil screen whether this motion be in a straight path or in a. curved one. Other modifications may be resorted to within the spirit of the appended claims.

We claim:

1. In an apparatus for decorating the curved surfaces of articles by a stenciling process, a stencil screen, a squeegee support positioned above the screen, a squeegee holder mounted on the support, said holder having a bifurcated lower end, ya retractable pin projecting through one of the furcations of said lower end and engaging the other furcation thereof and bridging the said iurcations, a squeegee'pivotally suspended from the pin, and spring means normally maintaining the pin in position against dislodgment.

2. In an apparatus for decorating the curved surfaces of articles by a stenciling process, a horizontally: reciprocable stencil screen, a substantially horizontally disposed squeegee support positionedabove the screen, a clamp mounted for axial adjustment on the horizontal support, there being a vertical guideway in the clamp, a. squeegee holder disposed in the guideway and vertically movable therein, means for adjusting the position of the holder in the guideway, clamping means for releasably securing the holder in the guideway in any desired adjusted position, and a squeegee pivotally suspended from the lower end of the holder.

3. In an apparatus for decorating the curved surfaces of articles by a' stenciling process, a horizontally reciprocable stencil screen, a horlzontally disposed squeegee support positioned above the screen, a clamp mounted for axial adjustment on the horizontal support; there boing a vertical guideway in the clamp, a squeegee holder disposed in the guideway and vertically movable therein, means for adjustingthe posi- .tion of the holder in the guideway, said holder having a bifurcated lower end, a retractable pin projecting through one of the nfurcations of said lower end and engaging vthe other furcation thereof and bridging the furcations, a. squeegee 'pivotally suspended from the, pin, and spring means normally maintaining the pin in position against dislodgment.

4. In an apparatus for decorating the curved surfaces of articles by a stenciling process, a horizontally reciprocable stencil screen, a horizontally disposed rock shaft disposed above the screen, a lifting member pivoted'to the shaft,

means for swingingithe lifting member through;

a. limited arc, a squeegee support pivoted to the shaft and capable ofswinging movement relacured to the support, a squeegee carried by the rollingllne Contact with each other at each i holder, and means releasably locking the support decorating stroke of the screen. However, .the

`decorative stroke of the screenv on alternate bottles is performed in opposite directions. I From* the above description it is thought that th'e versatility of vadjustment of the 'stenciling apparatus to accommodate all Amanner of bottles or other ware, as well as the many advantages thereof, will be fully understood without further elaboration. While the invention has beenillustrated and described in connection with an apparatus for decorating the curved tapered shoulder portions of the bottles, it obvious that-b`y slight modification thereof, the apparatus may serve to decorate the cylindrical sides of bottles tions therein, a retractable plunger carried by the supportl and selectively receivable in said notches, and a squeegee mounted on the support.

6. In an apparatus for decorating the curved surfaces of articles, a horizontally reciprocable stencil screen, a horizontally disposed rock shaft disposed above the screen, a lifting member pivoted to the shaft, said lifting member being capable of swinging movement on the `shaft through a limited arc from a lowered position to an elevated position and vice versa, means for reciprocating the screen, cam means for elevating the lifting member as the screen approaches the end of its stroke in either direction, a squeegee support pivoted to the shaft, means connecting the support to the lifting member, and a squeegee mounted on the support.

. 7. In an apparatus for decorating the curved surfaces of articles, a horizontally reciprocable stencil screen, a horizontally disposed rock shaft vdisposed above the screen, a lifting member pivoted to the shaft, said lifting member being capable of swinging movement Aon the shaft through a limited arc from a lowered position to an elevated position and vice versa, means for reciprocating the screen, 4cam means for elevating the lifting member as the screen approaches the end of its stroke in either direction, a squeegee support pivoted to theshaft, means releasably locking the support to the lifting member -in a pluralityof adjusted positions, and a squeegee mounted on the support.

8. In an apparatus forr decorating the curved surfaces of articles, a horizontally reciprocable stencil screen, a horizontally disposed rock shaft disposed above the screen, la lifting member pivoted to the shaft, said lifting member being capable of swinging movement Aon the shaft through a limited arc from a lowered position to an elevated positionand viceversa, a piston motor including a reciprocable piston lfor actuating the screen, a'vertically movable cam member for elevating the lifting member, a slide member connected to the piston for reciprocation therewith, and a pair of cams mounted on the slide member and alternately movable upon movement of the slide member into engagement with the cam member to elevate the latter.

9. In an apparatus for decorating the tapered shoulder portions of bottles and like articles byy a stenciling process, a support, a stencil screen mounted for oscillation in a horizontal plane above the support, a standard on the support beneath the screen, a tiltable cradle pivoted to' the standard, means for clamping the cradle-to the standard in a plurality of adjusted positions, a bottle support mounted on the cradle, a rotatable chuck on the bottle support, means 'for 'adjusting the position of the bottle support on the vcradle axially of the chuck, a splined shaft rotatably mounted von the bottle support-means connecting the chuck and shaft in driving relationship, a gear slidable on the shaft, a driving gear meshing with the .other gear, and means for rotating the driving gear alternately in opposite beneath the screen, atiltable cradle pivoted to the standard, means for. clamping the cradle to the standard in a plurality of adjusted positions, a bottle support mounted on the cradle, a rotatable chuck on the bottle support, means for adjusting the position of the bottle supporton` port, a stencil screen mounted for reciprocation .'in a horizontal plane above the support, a rotatable bottle supporting chuck disposed beneath the scre'en, a reciprocable rack, means for reciprocating the rack, means translating reciprocal motion of the rack to alternate rotation oi' the chuck, a second reciprocable rack, an oscillatable beam mounted on the support for swinging movement about a vertical axis, means translating reciprocation of the first rack to oscillation of the beam, means translating oscillation of the beam to reciprocation of the second rack, and means translating oscillation of the second rack to reciprocation of the screen.

12. In an apparatus for decorating the curved Isurfaces of articles Vby a stenciling process, a

support, a stencil screen mounted for oscillation in a horizontal plane above the support, a rotatable bottle supporting chuck disposed beneath the screen, a reciprocable rack, means for reciprocating the rack, means translating reciprocal motion of the r'ack to alternate rotation of the chuck, a second reciprocable rack, an oscillatable beam mounted on the support for swinging movement about a horizontal axis, a'cam member adjustably mounted on the beam for movement toward and away from the axis of oscillation thereof, a cam groove on the second rack in which the cam member travels to translate oscillationl of lthe beam to reciprocation of the second rack, and means translating reciprocation of the second rack to oscillation of the screen.

13. In an apparatus for decorating the curved surfaces of articles by a stenciling process, a support, a stencil screen mounted for oscillation in a horizontal plane above the support, a rotatable bottle supporting chuck disposed beneath the screen, a reciprocable rack, means for reciprocating the rack, means translating reciprocal motion of the rack to alternate rotation of the chuck in opposite directions, a second reciprocable rack, an oscillatable beam mounted on the support for swinging movement about a' ,horizontaP axis, a cam member adjustably mounted on the beam for movement toward and awayrfrom the center of oscillation thereof, means connecting the cam member and second rack to effect reciprocation of the latter, and means translating reciprocation of the second rack to oscillation of the screen.

' ALBERT S. JACKSON.

' CLARENCE A. HEYNE.