US2909116A

US2909116A - Adjustable silk screen device

Info

Publication number: US2909116A
Application number: US603198A
Authority: US
Inventors: Earl D Moore; Richard J Reed
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-08-09
Filing date: 1956-08-09
Publication date: 1959-10-20
Anticipated expiration: 1976-10-20

Description

Oct. 20, 1959 E. D. MOORE ET AL 2,909,116 ADJUSTABLE snx SCREEN DEVICE Filed Aug. 9, 1956 i I I I 4/ 43 Z6 4 l 'I I/ \\4J INVENTOR. 54,91. 0, M0035 RICH/4E0 J. ?Ff0 BY The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

The present invention relates to a silk screen device and more particularly to an adjustable device for accommodating diiferent sizes of workpieces that are to .be marked.

Various kinds and shapes of duplicating devices are known in the printing art and many employ a'stenciling screen formed of open meshed silk through which pigment is forced. The most common type of silk screening device presently employed in the art consists of a work supporting element and 'a silk screening element that is hingedly connected to the work supporting element. Heretofore, the work supporting element has been grooved or contoured to accommodate one particular size and shape of workpiece and the two elements have been permanently hinged together. While this arrangement has been widely used and has been quite successful, it has the main disadvantage of being a very costly item and when only a few items are to be marked or stenciled the cost per unit of production is high.

The invention disclosed herein is for a silk screening device that is readily adaptable to run small production quantities at a most economical cost. The customary supporting element heretofore employed in like devices is no longer required, and an electro-magnetic element is used to hold various sizes and shapes of workpieces. The silk screening lid is hingedly connected to a platform which can be raised or lowered, and workpieces of various heights can be readily accommodated by the device.

It is therefore a general object of the present invention to provide a silk screening fixture that will accommodate multiple sizes and shapes of workpieces that are to be marked or painted.

Another object is to provide an adjustable fixture for silk screening workpieces wherein said workpieces are held in position by electro-magnetic means.

Other objects and advantages of the present invention will be more readily appreciated as the invention becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawing wherein:

Figure 1 is a perspective view showing the complete invention; and

Figure 2 is a side view of a device constructed in accordance with the present invention.

Referring now to the drawing wherein like reference characters designate like or corresponding parts throughout the several views, there is shown in Figure 1 a base plate 11 having four upstanding brackets 12-15, inclusive, attached thereto by means such as screws 16. A top flange plate 17 is attached to the top of each upstanding bracket, and a screw 18 is rotatably mounted between each flange plate 17 and the base plate 11. A sprocket 19 is attached to each screw 18, and a continuous sprocket chain 21 engages each sprocket 19. A

Patented Oct. 20, 1959 shaft 22 is also rotatably mounted adjacent to bracket 12 between the top plate flange 17 and the base plate '11, and a handwheel 23 and a spur gear 24 are attached to the end portions of said shaft 22. Gear 24 engages with gear 25 that is attached to screw 18, and it can readily be understood that when handwheel 23 is rotated,

all four screws 18 will be rotatably driven thereby.

Referring now to Figures 1 and 2 of the drawing, there 'is shown a rectangular frame 26 that is threadedly engaged at the four corners with the four screws 18. It

should be obvious that by turning the handwheel 23, this frame 26 can be raised or lowered in height. As better shown in Figure 2, a hinge plate 27 is slidably attached to frame 26, and can be locked in any desired position by means of locking screw 28. One-half of a pianotypeghinge 29 is attached to hinge plate 27 and the mating half-hinge 31 is attached to a silk screen frame 32 by means of hinge pin 33.

'The silk screen frame may be any conventional type well known in the art, and might consist of a wooden framework covered by a silk screen on which is formed the design desired to be printed. When it is desired to change silk screen frames, the hinge pin 33 can be removed from the two hinge halves, thus separating the silk screen frame from the hinge plate 27. Another frame can then be placed in position and, upon replacing the hinge pin, the newly inserted frame is ready for operation. As the hinge plate 27 is slidably adjustable along the frame 26, various sizes of silk screen frames can be accommodated and therefore savings in material can be had, as the frame need only be of the size as required by the design to be printed.

Referring again to Figure l of the drawing, it can be seen that a magnetic chuck 34 is attached to base plate 11 and fits within the frame 26 so that there is clearance between the frame 26 and the chuck 34, thus permitting the frame 26 to be raised or lowered. The magnetic chuck 34 might be of any conventional type well known in the art, and might be either the permanent magnetor electro-magnetic type. The top surface of the magnetic chuck 34 serves as the work surface for mounting the workpieces that are to be marked or painted. For purposes of illustration, there are shown two

small parts

35 and 36 which are positioned between guide plates 37. The guide plates 37 can be made of any suitable magnetic material, and of course their sizes and shapes will be dependent upon the nature of the workpieces that are to be marked. The illustration shown in Figure 1 is best suited for non-magnetic workpieces such as nonmetallic terminal boards and the like. These types of parts will not be affected by the magnetism of the chuck and can be removed therefrom without demagnetizing the chuck 34. Thus once the guide plates 37 are placed in the desired position the current to the chuck 34 can be left on, thus assuring that the guide plates 37 will stay in the proper position throughout a production run. However, metallic parts could be marked equally well on the device herein described, as commercial demagnetizers are commonly employed with various magnetic chucks.

In operation, the half-hinge 31 on silk screen lid 32 is connected with the half-hinge 29 on hinge plate 27 by means of hinge pin 33. The hinge plate 27 is then moved forwardly until the tang 38 on silk screen lid 32 can be engaged with the slot 39 on locking bar 41. It can be seen that the front rail of the frame 26 is provided with a longitudinal slot 42 and that locking bar 41 can be moved along this slot so that the tang 38 will engage slot 39. A screw 43 is provided to lock the locking bar 41 in a fixed position. The locking bar 41 is provided in order to more firmly hold the silk screen lid in position so that on application of the ink or dye to the silk screen no movement will take place and thus blurring or smearing of the ink on

parts

35 and 36 will be avoided.

The next step of the operation is to position a

sample part

35 or 36 on the magnetic chuck and then raise or lower frame 26 by means of handwheel 23 until the silk screen is properly positioned over the sample part. The guide plates 37 are then positioned so that the sample part will be in the proper position to receive the design or lettering that is to be applied. When the guide plates 37 are in proper position, the magnetic force of the chuck is applied and this force will then hold the guide plates 37 in position. Once the frame 26 is adjusted in height to accommodate a particular part no further adjustment is required for a production run involving that particular part, and thus a large quantity of parts can be readily marked or painted.

As illustrated in the drawing, two difierent parts are mounted on the magnetic chuck at the same time. Of course, the thickness or height of these parts should be substantially equal in order that the silk screen lid 32 can be properly positioned over these parts.

It can thus be seen that the invention disclosed herein readily accomplishes its objects and that in order to mark or paint different designs, only the silk screen lid need be changed. This change can be made very quickly as ,it merely entails unhinging one lid and hinging another in place.

Obviously many modifications and variations of the present invention are possible, and it should be understood that the foregoing disclosure relates to only a preferred embodiment of the invention.

What is claimed is:

A silk screen device comprising, a base plate, a magnetic chuck attached to said base plate, metallic holding means adaptable for positioning on said magnetic chuck parts to be silk screened, a plurality of brackets attached to said base plate, a plurality of screws rotatably support by said brackets substantially perpendicular to said :base plate, a rectangularly shaped frame threadedly attached to said screws, said frame comprising front and back rails and two side rails, said front rail having a longitudinal slot substantially the entire length thereof, the inside dimensions of said frame being larger than the outside dimensions of said magnetic chuck whereby said frame is positionable around said magnetic chuck, at least one locking bar slidably attached to said front rail of said frame through said longitudinal slot, a hinge plate slidalbly connected to the two side rails of said frame and movable in a plane parallel with the top surface of said base plate, and a silk screen lid hingedly connected to said hinge plate and having a tang thereon adaptable for engaging said locking bar. 7

References Cited in the file of this patent UNITED STATES PATENTS Lindley et a1 Nov. 16, 1897 1,840,073 Williams Jan. 5 1932