US3425344A - Rotary screen decorating machine - Google Patents

Description

Feb. 4, 1969 B. E. JAEGER ROTARY SCREEN DECORATING MACHINE Sheet Filed Oct. 20, 1965 R 5 R E N 06 N E mm E w m 4N N\ RN Q 3 f\\ N o o WW/ Q 3 E Feb. 4,, 1969 B. E. JAEGQER 3,425,344

ROTARY SCREEN DECORATING MACHINE Filed Oct. 20, 1965 Y I Sheet 2 of 2 I INVENTOR. BENJAMIN 5. JA 5652 ATTORNEYS.

United States Patent 2 Claims ABSTRACT OF THE DISCLOSURE A silk screen stencil decorating apparatus for bottles wherein the stencil is an arcuate surface consisting of a portion of the peripheral wall of a continuously rotating vertical drum with the articles moved bodily continuously past the drum at the same speed as the surface speed of the drum. A vertical squeegee inside of the drum at the line of tangency presses ink through the stencil against the bottle and ink is flowed downwardly along the squeegee and continuously returned from a well at the bottom of the drum to the upper end of the squeegee.

This invention relates to the application of surface ornamentation or indicia by the silk screen process and to novel apparatus for effecting such application.

The art of silk screen printing is well known and widely practiced. As conventionally performed, the surface to be printed or decorated is placed flat on a table or other support and the silk screen, which serves as a stencil, is stretched in a rectangular frame which is disposed horizontally above and close to the surface to be decorated. A supply of ink or other coloring material is deposited on the upper surface of the screen and a squeegee is passed over such upper surface to spread the liquid or semi-liquid coloring material and squeeze it through portions of the silk screen which have not been masked over by coating or the like and against the surface to be decorated.

Virtually all silk screen printing or decorating is carried on by means of a horizontally disposed flat screen which is disposed above the surface to be printed or decorated. I have found that important advantages of silk screen printing or decorating are attained by employing a cylindrical silk screen unit disposed on a vertical axis, the printing being applied in a vertical plane against a vertically disposed surface to be printed or decorated.

In the prior art there is an isolated instance of apparatus for silk screen printing by means of a silk screen supported on a cylindrical drum, the drum being mounted for rotation on a horizontal axis and the surface to be printed comprising a continuous web or strip of textile fabric adapted to pass beneath the drum. This patent is to Stein et al., No. 2,928,340 dated Mar. 15, 1960. A further prior art patent, Jackson et al., No. 2,461,281 dated Feb. 8, 1949, proposes the practice of silk screen printing or stencilling by means of a flat rectangular stencil mounted in a vertical plane with a squeegee which is adapted to reciprocate vertically across the surafec of the flat silk screen. Neither of these prior art patents disclose apparatus capable of producing the results aimed at herein.

While the apparatus of the present invention may be variously employed in effecting silk screen printing, the following discussion relates particularly to the employment of the apparatus in connection with printing or decorating the surfaces of objects such as bottles and jars while such bottles and jars are disposed upright. Furthermore, while the principles of the present invention are applicable to printing upon or decorating surfaces of bottles of various shapes, the particular instance illustrated herein by way of example involves printing or decorating of bottles having a fiat or nearly flat surface to be printed since certain special problems are presented in printing on generally flat bottle surfaces.

As stated heretofore, silk screen printing and decorating as commercially practiced is substantially universally performed in a horizontal plane. Bottles coming from a fabricating machine and passing through an annealing lehr and automatic inspection machines are always in an upright position since they stand firmly on their own bottoms in such position without other support and are generally easiest to convey, inspect and otherwise handle and deal with in an upright position. Accordingly, in the commercial decoration or printing of bottles by the silk screen method, it has heretofore always been required that the bottles or jars or similar objects, which approach the decorating or printing machine in an upright position on a conveyor, be tipped over onto their sides and oriented with respect to the printing or decorating apparatus in this position. :Following the conclusion of the printing or decorating step, in order to handle the bottles or jars in the conventional manner for inspection, packing, lfilling or such other manipulations as may be desired, it is necessary to again set the bottles upright for passage along the usual conveyors.

Since these tipping over and setting up operations of the bottles, jars or the like must be carried on automatically to be commercially practicable, machinery required for performing these functions is in many instances more costly and more complicated than the usual decorating or printing machinery itself. Despite the foregoing difiiculties of printing bottles in a horizontal plane and the fact that these difliculties are vexacious and well recognized, no satisfactory means for printing or decorating bottles by the silk screen method while such bottles are in an upright position has heretofore been devised or proposed.

Apart from the difficulties incident to orienting articles for printing in a horizontal plane as now conventionally practiced, the continuous printing of a succession of articles by means of a flat silk screen usually involves the employment of a reciprocating screen or a reciprocating squeegee. Bottles and jars, for instance, are usually printed or decorated by employing a horizontal flat reciprocating silk screen frame. Since printing or decorating on articles of this kind must be carried on at a high rate of speed to be commercially practicable, the employment of a reciprocating screen with the jarring and wear and tear incident to rapid acceleration and deceleration of the screen and its supporting mechanism at a velocity of possibly several hundred times a minute greatly reduces the efliciency of operation of decorating apparatus of this character.

In the apparatus of the present invention the silk screen stenciling surface is applied to a drum or cylinder and the drum or cylinder is rotated continu'busly on a vertical axis, thus avoiding the rapid accelerations and decelerations which greatly reduce the efficiency of currently employed reciprocating silk screen apparatus and also dispensing with the necessity for tipping upright articles to their sides for eifectin g the printing operation.

While the vertical cylinder or drum principle of silk screen stenciling may be employed in various adaptations the particular apparatus set forth herein is designed particularly for printing or decorating on the side walls of articles which are flat or nearly flat. In the specific apparatus disclosed the fiat bottles or bottles having fiat portions to be pri1tted or decorated are moved past the stencil cylinder or drum in a straight line in substantial tangency therewith a d at the same surface speed as that of the rotating stencil drum or cylinder. In the case of articles having an arcuate surface to be decorated wherein the radius of curvature is fairly large compared to the cross-sectional size of the bottle, the bottle may similarly be moved past the drum along an arc corresponding to the curvature of the bottle surface to be printed whereby such surface is similarly moved past the drum surface in tangency therewith and at the same surface speed as the drum.

While a single specific embodiment of the principles of the present invention is illustrated in the accompanying drawings and described in detail in the following specification, it is to be understood that such embodiment is by way of example only and that various mechanical modifications may be made without departing from the spirit of the invention, the scope of which is limited only as defined in the appended claims.

In the drawings:

FIG. 1 is a general somewhat fragmentary top plan view of one form of the apparatus of the present invention; and

FIG. 2 is a cross sectional view taken approximately on the line IIII of FIG. 1.

Like characters of reference denote like parts in the several figures of the drawings. In general, the machine disclosed herein by way of illustrating the novel principles of the present invention comprises two main interrelated and cooperating components, a printing and decorating component designated generally by the reference numeral in FIGS. 1 and 2 and an article conveying and positioning component designated generally by the reference numeral 11 in FIGS. 1 and 2.

In the form of the present invention set forth herein by way of example, and still referring generally to the structure shown in the drawings, the article handling portion of the machine comprises a continuous belt conveyor 12 which carries a row of articles to be decorated to and away from the decorating component 10. As the articles approach the printing or decorating component 10 they will, in order to assure an adequate supply of articles for the machine, be spaced relatively closely along the conveyor 12.

Accordingly, means are provided for receiving bottles or similar articles and spacing them at proper intervals for delivery to a bottle clamping apparatus designated generally by the reference numeral 13. Such spacing means comprises a horizontal feed screw 15 mounted above conveyor belt 12 and an opposed spring backed vertical plate 16 is mounted parallel to the feed screw 15 and spaced therefrom so that bottles on the conveyor approaching the decorating component pass between the feed screw 15 and plate 16. As shown in FIG. 1, plate 16 is attached to rods 17 which project from fixed casings 18 which contain springs for urging the rods 17 and plate 16 toward feed screw 15.

The bottle clamping apparatus 13 comprises vertically spaced pairs of sprockets shown at 20 and 21 in FIG. 1 connected by chains 22. The pairs of sprockets 20 and 21 are fixed to operating shafts 23 and 24 and bottle clamping means are carried by the links of chains 22. As shown in FIGS. 1 and 2, plate members 26 are attached to the upper and lower chains 22 and vertically spaced pairs of bottle clamping jaws 27 project from the vertical mounting plates 26.

As the chains pass about the sprockets the radial di vergence of the clamp jaws 27 causes them to assume an open unclamping position as clearly shown in FIG. 1, Whereas as the jaws 27 move to the straight part of the chains 22, they move to a generally parallel position in which they are adapted to engage opposite sides of bottles 29, likewise as shown in FIG. 1.

Feed screw 15 is timed to relase bottles 29 to conveyor belt 12 at such frequency that they pass to the open jaws 27 of the clamp means as such jaws move toward the straight parts of the chains 22 which lead to and past the printing component 10. Thus individual bottles 29 are engaged by the jaws and move to and past the printing component 10 and the surfat c p ed Of the chains 22 and bottles 29 is timed to match the surface speed of a rotating printing drum designated generally by the reference numeral 55.

In FIG. 2 the reference numeral 30 designates a drive shaft which may comprise the output shaft of a conventional speed reducer which is driven from the usual electric motor. Such drive means is well known and neither the electric drive motor nor the speed reducer are illustrated herein. In the alternative, shaft 30 may merely comprise a countershaft driven from the output shaft of a speed reducer.

A chain and sprocket connection 31 connects drive shaft 30 with a shaft 32 which comprises the pulley or sprocket shaft of conveyor 12 at the delivery end thereof. As shown in FIG. 2, drive shaft 30 connects with a shaft 33 of a mitre gear box 34 by a chain and sprocket connection 35. Shaft 33 is connected by a chain and sprocket connection 37 with a mitre gear box 38 which has a vertical output shaft 39 which drives sprocket shaft 24 of the clamping mechanism 13 by means of a chain and sprocket connection 40.

Feed screw 15 is driven from the companion sprocket shaft 23 by means of a chain and sprocket connection 41 which extends to a mitre gear box 42 from which feed screw 15 is driven.

As also illustrated in FIG. 2, drum 55 of the printing or decorating component is fixed to the upper end of a drive shaft 56 which is supported in bearings 57 and 58 carried by the machine framework and shaft 56 is operated by a chain and sprocket connection 59 from mitre gear box 34. The printing component 10 of the present invention may be substantially identical with the corresponding printing component of my concurrently filed application on apparatus for printing on round articles and reference may be had to that application as to any details of construction of the printing component 10 which may not be fully illustrated herein.

Drum 55 comprises a vertical hollow cylindrical member 65 having three rectangular openings 66 in its peripheral side wall, the openings 66 being equally spaced in a circumferential direction. The silk scren stencil members are mounted over such openings as at 68 in FIG. 2. The bottom end of cylindrical member 65 is closed as at 69 whereby the drum 55 comprises a well for receiving a supply of liquid or semi-liquid printing material.

The means for supplying such printing material continuously to the printing zone of the silk screen stencils 68 will now be described. The printing material may be referred to herein generically as ink although in printing and decorating on glass bottles, for instance, the same will usually comprise a ceramic slip which may be fired to a vitreous condition after application to the surface of the bottle. Any other fluid or semi-fluid printing material may be employed, including organic inks such as epoxy resins and others.

It is conventional to wipe a squeegee against one surface of a silk screen stencil while the opposite surface of the stencil lies against the surface to be printed or decorated. The squeege presses the printing ink through the stencil onto the surface to be printed. In the present instance a similar operational relationship is employed although the relative movements of the three component elements, namely, the stencil, the squeegee, and the work surface, are novel.

In the present invention the stencil lies in an arcuate plane and, during the actual printing operation, the stencil and the surface to be printed upon are supported in tangency with respect to each other. The aforesaid squeegee is disposed vertically at the interior of the cylindrical stencil so as to bear thereagainst along the line of tangency between the stencil surface and the surface to be printed upon. The surface of the bottle or other article which is to be printed upon is moved past the drum in such tangency and at a speed equal to the surface speed of the rotating cylindricalstencil. The squeegee itself is stationary during the printing operation although, as will presently appear, means are provided whereby the squeegee is periodically moved bodily toward and away from engagement with the interior surface of the cylindrical squeegee so as to be in engagement therewith only during the actual printing operation.

The squeegee and ink feeding mechanism is designated generally by the reference numeral 72 in FIG. 2, and is mounted as a uint on an inverted L-shaped bracket 73 which is pivoted to the machine framework as at 75 in FIG. 2. By means of this pivotal mounting the entire squeegee and ink feeding mechanism may be swung upwardly out of the drum 55 for cleaning, setting up, and for various other purposes.

Referring particularly to FIG. 2, the squeegee itself comprises the usual rubber or other strip 76 mounted upon a block 78 which is carried by a bracket 79, the bracket 79 being mounted for horizontal movement from left to right as viewed in FIG. 2 for moving the squeegee cyclically against the interior of the cylindrical stencil to effect successive printing operations. For this purpose bracket 79 is fixed to a pair of slide bearing members 80 which are slidably mounted on a pair of shafts 82 which are fixedly mounted to the underside of the horizontal protion of L-shaped bracket 73.

An extension coil spring 84 normally urges the carriage structure comprising bracket 79 and slide bearings 80 to the left as viewed in FIG. 2 to urge squeegee 76 against the silk scren members 68 and a cam mechanism is provided for retracting the squeegee between printing operations. Coil spring 84 connects between the extreme left hand portion of bracket 73 and a point on bracket 79 between the slide bearings 80.

The cam for withdrawing the squeegee from the screen stencil surface between successive printing operations comprises an internal flange formation at the upper end of the cylindrical member 65 of drum 55, such camming flange being designated 85 in FIGS. 1 and 2. A cam follower roller 86 fixed to the under side of a forward portion of the carriage comprising bracket 79 and bearings 80 is held in peripheral engagement with cam flange 85 by the action of coil spring 84. In FIG. 1 cam 85 is illustrated in a position midway in a printing operation whereas in FIG. 2 the parts are illustrated midway between successive printing operations wherein the squeegee is withdrawn from engagement with the interior of the stencilling screen surface.

The means for maintaining a continuous supply of ink at the interior surface of each of the silk screen stencil portions 68 of the drums '55 in the vicinity of the printing zone and more particularly ahead of the vertical operative edge of the squeegee 76 will now be described. An ink feeding belt 90 extends about a pulley 91 carried by bracket 73 and a pulley 92 carried by an arm 93 extending downwardly from bracket 73. Pulley 91 is driven by belt connection with a pulley 95 on the output shaft of a reducer unit 96 which is driven by an electric motor 97. Motor 97 and reducer 96 are mounted as a unit on bracket 73 for pivotal movement therewith.

A channel or chute member 100 carried by the upper end of arm 93 has its upper end lying closely adjacent to or in scraping relation with the periphery of belt 90 as it passes about upper pulley 91 and the lower end of the inclined channel member 100 lies closely adjacent to the upper end of squeegee 76. A supply of liquid or semiliquid decorating material, such for instance as a ceramic slip in the case of ceramic stencilling of bottles, is maintained in the interior bottom of drum 55. Pulleys 91 and 92 rotate in a counterclockwise direction as viewed in FIG. 2 and belt picks up a supply of ink on its surface and carries the same upwardly whereupon it is scraped into channel and flows downwardly to a deflector plate 101 carried by squeegee block 78 which guides the ink to the operating edgeof squeegee 76. The ink flows downwardly along or closely adjacent to squeegee 76 at the side thereof which is toward the viewer in FIG. 2 and since drum- 55 rotates in a clockwise direction as viewed in FIG. 1, the ink is fed to the stencil and squeegee mechanism in a highly eflicient manner for distribution along the effective portion of the interior of stencils 68.

Means are provided for holding the squeegee mechanism in an extreme right-hand position as viewed in FIG. 2 to facilitate pivotal movement thereof about pivot shaft 75 to raise the same drum 55 without interference with interior portions of drum 55. Such means comprises a latch mechanism shown in my aforesaid copending application which also illustrates a toggle clamp arrangement for selectively locking the squeegee mechanism in its operative position within the drum 55.

The drum 55 may be provided with one or more peripheral wall openings 66. In the present instance three such openings are employed, merely byway of example. The sprockets 20 and 21 are timed to rotate at such speed that the outer surfaces of the clamping jaws 27, which are substantially in the plane of printing, move at a surface speed equal to the surface speed of drum 55 and the stencils 68. Also the center to center distance between each pair of clamp jaws 27 is equal to the peripheral distance between the centers of the stencil openings in drum 55. If only one stencil opening is employed then the pitch of the pairs of clamp jaws will be equal to the circumference of drum 55.

Various means may be employed for interchangeably applying stencils to the exterior of drum 55. By way of example, each stencil 68 may be attached to a flat sheet metal frame, the framing portions being of substantial width in the plane of the stencil to provide rigid support for the stencil while the relatively thin sheet metal of the frame flexes readily to permit the same to be flexed arcuately against the periphery of the drum 55, to which the sheet metal frame of the stencil may be detachably secured by screws or in various other ways.

It is to be understood that the term ink as used herein and in the appended claims is intended to cover any fluid or semi-fluid printing or decorating medium capable of being applied by a stencilling process.

It is further to be understood that the term squeegee as used herein embraces any wiping or ink expressing means which may be employed at the interior of the stencil.

While the stencilling drum is referred to herein as having a generally vertical axis, it is to be understood that this position of the drum axis is relative and the drum axis may vary somewhat from the vertical, as in printing on tapered bottles and tumblers and other inclined surfaces.

What is claimed is:

1. Apparatus for imprinting side wall surfaces of a series of articles comprising imprinting means and article presenting means, said imprinting means comprising a cylindrical drum having a generally vertical axis and stencil means disposed in a peripheral wall portion thereof to form an arcuate continuation of said wall portion, means for continuously rotating said drum, and a relatively stationary vertical squeegee within said drum engageable against the interior surface of said stencil means along a vertical line for wiping action against said stencil means upon rotation of said drum, said article presenting means comprising means for successively engaging each of a series of articles and means for continuously moving said articles bodily along a path generally tangent to said drum at said squeegee, said moving means being synchronized with said drum rotating means to move said articles at a surface speed equal to the surface speed of said drum, the lower interior of said drum comprising an ink well, and means for raising ink from said well and discharging the same in the vicinity of the upper end of said squeegee for gravity flow downwardly adjacent thereto for application through said stencil means and whereby the excess ink returns to said well 2. Apparatus according to claim 1 wherein said article engaging and moving means is adapted to maintain said series of articles at a spacing substantially equal to the pitch of said stencil means whereby successive articles engage the stencil means in predetermined registry therewith.

References Cited UNITED STATES PATENTS Lafiitte 101-120 Zeitinger 101-120 Smith et al. 101-124 Simonton 101-124 Davies 101-35 Hakogi 101-40 McKay 101-37 Rudolph et a1 101-40 Rossi 101-126 WILLIAM B. PENN, Primary Examiner.

US. Cl. X.R.

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