US3017825A - Multiple printing squeegee moving mechanism of an automatic screen printing machine - Google Patents

Description

Jan. 23, 1962 HISAKICHI ICHINOSE 3,017,825 MULTIPLE PRINTING SQUEEGEE MOVING MECHANISM OF AN AUTOMATIC SCREEN PRINTING MACHINE Filed Dec. 15, 1959 2 Sheets-Sheet l HIS/1 KICHI IcHz/vosE INVENTOR.

A TTORNE V5 HISAKICHI ICHINOSE 3, INTING NG MECHANISM OF AN AUTOMATIC SCREEN PRINTING MACHINE I Filed Dec. 15, 1959 2 Sheets-Sheet 2 Jan. 23, 1962 MULTIPLE PR SQUEEGEE MOVI lilllilav'i HISAKICHI ICHINosE INVENTOR.

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3,017,825 MULTIPLE PRINTING SQUEEGEE MOVING MECHANISM OF AN AUTUMATEC SCREEN PRINTING MACHINE Hisakichi Ichinose, 175 Z-chome, Koushieguchi Hyogo Prefecture, Koushien, Nishinomiya City, Japan Filed Dec. 15, 1959, Ser. No. 859,610 Claims priority, application Japan May 27, 11959 3 Claims. (Cl. ll123) The present invention relates to an improvement in means for raising and lowering squeegees in an automatic screen printing machine of the type having a driving roller at one end of an endless belt and a follower roller at the other end, and means for intermittently driving the driving roller to intermittently move the belt between the rollers, and on which machine there are a plurality of printing frames in which the squeegee printing means are installed such that they can be reciprocated transversely of the direction in which the belt moves. During the operation of such a machine, the squeegees are reciprocated to print on the cloth on the belt by spreading ink thereover through a pattern in the screens mounted on the printing frames during the times that the belt is not moving between positions. I 7

It is not uncommon in the screen printing art to have to move a single or double squeegee back and forth across a screen several times in order to produce the necessary image on the cloth being printed. As this is done, there is the possibility that the screen will be creased Or that the screen will be moved slightly thus causing the printed images to overlap on the cloth. It would be possible to move a larger number of squeegees across the screen only once or twice, but when a larger number of squeegees is used, the problem of lifting them from contact with the screen and again lowering them so that they contact the screen at the proper pressure becomes quite serious.

It is an object of the present invention to provide means for raising and lowering a plurality of printing squeegees simultaneously and such that they contact the printing screen at equal pressures so as to permit the use of a plurality of squeegees greater than two while at the same time not unduly complicating the apparatus. The means for accomplishing this object comprise a plurality of pairs of elevating members on which the ends of the squeegees are mounted, and a cam member is positioned under the elevating members at one end of the squeegees and a similar cam member is positioned under the elevating members at the other end of the squeegees. The cam members are movable in a direction perpendicular to the direction in which the belt on the machine moves as well as to the direction in which the squeegees extend over the belt, and these cam members have a plurality of grooves therein extending transversely to the direction in which the cam members are movable. There is one groove for each elevating member, and each groove of the portion of said grooves has an inclined surface on one side thereof and a surface perpendicular to the length of the cam member on the other side thereof. while each groove in the remainder of the grooves has an inclined surface on the other side thereof and a perpendicular surface on the one side thereof. The elevating members have inclined surfaces on the ends thereof which bear on the inclined surfaces on the sides of the grooves. The cam members are mounted on a reciproeating bed which is reciprocable in the direction in which the cam members extend. Spring means bear on the squeegees to urge them downwardly against the cam members.

The invention will now be more fully described with reference to the accompanying drawings, in which:

3,l7,825 Patented Jan. 23, 1962 FIG. 1 is a partial side view of the automatic screen printing machine with a multiple printing squeegee moving mechanism of this invention;

PEG. 2 is a side-view of the remaining part of the said automatic screen printing machine, the figures to be joined at line T-T at the right end of FIG. 1 and line T-T at the left end of FIG. 2;

FIG. 3 is the plan view of FIG. 1;

PEG. 4 is the plan view of FIG. 2, FIGS. 3 and 4 to be joined at line U-U at the right end of FIG. 3 and line U-U at the left end of FIG. 4;

FIG. 5 is a sectional elevation view, on an enlarged scale, of the principal parts of the multiple printing squeegee moving mechanism of this invention; and

F G. 6 is a sectional side-view taken on line XX in FIG. 5.

FIGS. 1 to 4 show the automatic screen printing machine to be equipped with this invention. Frame 1 extends the entire length of the machine, at one end of which is a driving roller 2 at the other end is a following roller 3. Between these rollers is stretched an endless belt 4 in such a way that the said belt 4 may be intermittently advanced in the direction shown by the arrow mark by intermittent revolutions of a driving roller 2. In this way, the following roller 3 is also revolved intermittently. On this endless belt 4, a plurality of printing frames 5 are arranged (FIGS. 2 and 4 show 10 printing frames) and all of them are held by main frame 6. Extending in the transverse direction of the said main frame 6 are several guide rails 7 (FIGS. 2 and 4 show 6 guide rails), on which squeegee holders 8 are placed so as to be movable reciprocally in the transverse direction of printing frames at the required time. These squeegee holders can be joined to each other throughout the full length of the frame, or occasionally a few of them can be mounted to move independently of the others. From these squeegee holders, two or more squeegees are hung in each printing frame so as to come in contact with screens which are stretched across the bottom of each printing frame. Color paste is stored between the said squeegees to print cloth through the screens 56 when the squeegees slide on the screens. At the entry end of the frame 1, the feeding device 9 for cloth 12 to be printed is installed so that the cloth 12 is continuously fed from the entry to the exit, being agglutinated on the endless belt in accordance with the advances of endless belt. At the exit of the frame, the dryer 10 is installed for the after-treatment of printed cloth as shown in FIGS. 1 and 3. The dryer it? is equipped with a cloth discharge apparatus fl.

H68. 5 and 6 illustrate the multiple printing squeegee moving mechanism of this invention. Parts 13, 14, 15, i6, 17 and 18 are printing squeegees. Part 19 is a beam rail, along which reciprocating bed 20 moves. Parts 21 are cam members having therein grooves 22, 23, 24, 25, and 27 respectively, each groove having one side thereof inclined as at 49, 50, 51, 52, 53 and 54. There are two cam members for each printing frame 5, one on each side of the said frame and extending parallel with guide rails 7. In grooves 22, 23, 24, 25, 26 and 27 of each cam member 21, are positioned elevating members 28, 29, 3t), 31, 32 and 33 each having an inclined face on the end thereof bearing on inclined sides 49, 50, 51, 52, 53 and 54 so that the said elevating members slide freely in the vertical direction in the slots of the reciprocating bed, there being two elevating members for each of printing squeegees l3, 14, 15, l6, l7 and 18 respectively. On the tops of elevating members 28, 29, 3t], 31, 32 and 33, are mounted side-wings 3 3-, 35, 36, 37, 33 and 39 on the respective printing squeegees.

As illustrated in FIG. 6, on both outside ends of reciprocatingbed 20 are mounted inner cylinders 41, being pivoted on pins 40, the said pins serving as fulcra. Spring 42 is positioned in each inner cylinder 41, and the upper part of each inner cylinder 41 is positioned in an exterior cylinder 44. Screw spindle 43 extends through each inner cylinder 41 and exterior cylinder 44 and is engaged with spring 42, the end part of screw spindle 43 projecting above exterior cylinder 44 having nut 45 threaded thereon. A projection 46 is provided on the exterior cylinder 44 which interlocks with concave groove 47 on the tops of both sidewings 34, 35, 36, 37, 38 and 39 of the printing squeegees. All printing squeegees 13, 14, 15, 16, 17 and 18 are thus pressed down so as to contact with the surface of screen 56 with the required pressure. This pressure may be easily controlled by adjusting nuts 45.

Furthermore, in case it becomes necessary to pull out printing squeegees for washing, etc., the dismantling of the printing squeegees may easily be accomplished by swinging exterior cylinders 44 in the direction of the arrow after lifting the said cylinders slightly so that projections 46 of exterior cylinder 44- may be removed from concave grooves 47 on both side-wings of each printing squeegee. The angle through which each exterior cylinder 44 can swing is limited since the lower end of inner cylinder 41 touches the side of reciprocating bed 20 when exterior cylinder 44 is swung in the direction of the arrow.

Referring to FIGS. and 6, the motion of the apparatus of this invention will be explained in more detail. In the position illustrated in FIG. 5, endless chain 48 coupled with both ends of cam member 21 is moving toward the left as indicated by the arrow. Elevating members 28, 29, 3t), 31, 32 and 33 are always pressed on corresponding inclined planes 49, 50, 51, 52 and.53 of cam member 21 by respective thrust springs 42. In FIG. 5, three elevating members 29, 31 and 33 are in the lower position in the bottom of grooves 25, 26 and 27. The three inclined planes 49, 50 and 51 in the remaining grooves 22, 23 and 24 on cam member 21 are causing the oppositely inclined planes of elevating members 28, 30 and 32 to slide upwardly so as to lift them. Consequently, printing squeegees 13, 14 and arranged on elevating members 28, 30 and 32 are lifted, thereby compressing corresponding thrust springs 42. In this state, the three printing squeegees mentioned above are separated from the surface of screen 56, and the other printing squeegees 16, 17 and 18 apply the color paste on the surface of screen 56, the said paste penetrating through the screen so as to accomplish the desired printing. Elevating members 29, 31 and 33 are never lowered below this elevation, since they are located at the bottoms 25, 26 and 27 of their respective grooves. Consequently, printing squeegees corresponding to elevating members 29, 31 and 33 always touch the surface of the screen 56 with the appropriate pressure. Furthermore, the vertical surfaces at the right side of grooves 25, 26 and 27 on cam member 21 come in contact with the vertical surfaces of the interlocked elevating members, so that reciprocating bed may be moved toward the left by the movement of cam member 21. Moreover, the arrangement of the printing squeegees shown in FIG. 5 is designed to equalize the feed of color paste at each printing squeegee by making the intervals between the printing squeegees which are in motion uniform. This arrangement and the number of the printing squeegees may be varied in any situation. (For example, the three squeegees to the left may be arranged to form one group and other three squeegees at the right a second group.)

When reciprocating bed 20 reaches the end of the leftward stroke, the three elevating members 28, and 32 may be lowered and other three elevating members 29, 31 and 33 may be raised by moving chain 48 slightly to the right. (Tolerance c is the difference between intervals a and b, interval a being the distance between the external sides of elevating members 28 and 33, and interval b being the distance between the outside vertical surfaces of cam member 21. This tolerance c is designed to make the elevating members slide smoothly in the grooves of the cam member.) In this way, when the bottom of groove 22 on the left end of cam member 21 is formed so as to have a dimension equal to the tolerance c, and the chain is moved a distance equal to /2c to the right, a clearance having a length /2c is formed at the bottom of concave groove 27 on the right end of cam member 21, thereby positioning every printing squeegee at the same elevation. In this position, all printing squeegees are in a condition of such light contact with the screen that the spreading out of colour paste may satisfactorily be checked by slight touching of printing squeegees on the surface of screen 56 and yet the screen will not be damaged by the said touching.

When chain 48 is moved further to the right when reciprocating bed 20 is moved toward the right, it should be understood that the cloth on the endless belt is moved forward one pitch by a separate driving mechanism, the position of the printing squeegees are the reverse of that in the leftward stroke described above. In other words, inclined planes 52, 53 and 54 press against the inclined planes of elevating members 29, 31 and 33, thereby elevating members 29, 31, 33 and printing squeegees 16, 17, 18 are lifted. Elevating members 28, 30, 32 and printing squeegees 13, 14, 15 are lowered. The reciprocating bed 20 may be moved to the right by the vertical surfaces 55 of grooves 22, 23, 24. Contacting the ver tical surfaces on elevating members 28, 30 and 32. In this way, printing during the return stroke may be accomplished satisfactorily by printing squeegees 13, 14, 15. By repeating the reciprocating motion mentioned above, printing may automatically and intermittently be carried out repeatedly. FIG. 5 shows an example of a six squeegee mover. The number of printing squeegees, however, may be varied as the occasion demands.

This invention, with the construction and operation as described above prevents overlapped printing due to reciprocating printing for one color and a result corresponding to that produced by several reciprocating strokes of conventional double printing squeegee systems may easily be accomplished within a shorter period of time in a single stroke. Furthermore, at the time when the motion of the squeegees is stopped, all printing squeegees may be placed in contact with the surface of the screen at a moderate pressure regardless of their motion at the ends of the stroke or intermediate of the ends of the stroke, thereby satisfactorily preventing spread of the color paste from the printing squeegees.

Iclaim:

1. In an automatic screen printing machine, the combination of a plurality of printing squeegees each having side wings projecting from the ends thereof, said squeegees being positioned in the vertical position and being substantially parallel to each other and parallel to the longitudinal direction of the machine, a plurality of pairs of elevating members, the elevating members of each pair being under the respective side wings of a printing squeegee and supporting the squeegee, a pair of cam members, one cam member being beneath the elevating members at one end of the squeegees and the other cam member being beneath the elevating members at the other end of the squeegees, said cam members being movable perpendicular to the longitudinal direction of the machine and to the direction in which the squeegees extend, said cam members each having a plurality of grooves therein extending transversely to the direction in which the cam members are movable, there being one groove for each elevating member, each groove in a portion of said grooves having an inclined surface on one side thereof and a surface perpendicular to the length of the cam member on the other side thereof, and each groove of the remainder of said grooves having an inclined surface on the other side thereof and a surface perpendicular to the length of the cam member on the one side thereof, said elevating members having inclined surfaces on the ends thereof bearing on the inclined surfaces of the sides of said grooves, and a reciprocating bed reciprocating in the direction in which said cam members are movable and on which 5 said cam members are mounted, and spring means hearing on said Squeegees urging said elevating members downwardly against said cam members.

2. The combination as claimed in claim 1 in which each of said spring means comprises a first cylinder pivoted on said machine for movement outwardly of the Squeegees at each end of each squeegee, a second cylinder s-lidably concentrically engaged with said first cylinder, a spring Within said cylinders, a piston rod extending through the end of the second cylinder and connected to said spring and having a nut threaded thereon, said second cylinder having a projection thereon bearing on said squeegee.

3. The combination as claimed in claim 1 in which said second cylinder has a hook-like member thereon and said first cylinder has an extension projecting beyond the pivotal mounting thereof, whereby said second cylinder can be lifted so the projection is lifted from the squeegee and then the spring means can be pivoted outwardly away from the machine for only a limited distance until the extension on said first cylinder abuts the 10 machine.

References Cited in the file of this patent UNITED STATES PATENTS Fordyce Nov. 7, 1950 2,651,988 Thomas Sept. 15, 1953

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