Screen printing machine with single-sided rack-and-pinion drive

Claim 2

In a screen printing machine including a table for supporting blanks to be printed and a screen overlying the blank, the improvement comprising: a squeegee drive bar extending across said table above said screen and carrying a squeegee assembly beneath the drive bar for contact with said screen; a pair of laterally spaced relatively thick support bars for supporting said drive bar on opposite sides of said table; a rack fixed to one of said support bars and extending parallel thereto; a drive bar motor mounted on said squeegee drive bar and carrying a spur gear driven thereby in mesh with said rack for causing said squeegee drive bar to move relative to said rack, said support bar carrying said rack further carrying a ball bushing rod fixed thereto and extending parallel to said rack, and open sided ball bushing means carried by said squeegee drive bar and embracing said rod with the surface of the rod contacted by said bushing means being the surface most remote from said rack, and the teeth of the rAck extending from the surface of said rack which is most remote from said support bar to absorb the reactive force created by opposition to movement of said squeegee assembly over said screen.

Claim 3

A screen printing machine as claimed in claim 1, wherein said rack is fixed to the outside of said one support bar, said ball bushing rod is cantilever supported throughout its length on the inside of said one support bar and said open sided ball bushing means has a C-shaped contact surface which contacts the periphery of said rod in excess of 180*.

Claim 4

The screen printing machine as claimed in claim 2, wherein said other support bar is F-shaped in cross sectional configuration defining an internal groove, and the end of said squeegee drive bar carries at least one roller bearing positioned within said groove and movable therealong.

Claim 5

The screen printing machine as claimed in claim 1, wherein said other support bar is F-shaped in cross sectional configuration with an internal groove within the inside surface thereof, and the end of said squeegee drive bar carries at least one roller bearing positioned within said groove and movable therealong.

Claim 6

In a screen printing machine including a table carrying a blank to be printed and a screen overlying the same and a squeegee drive bar horizontally movable across the table and parallel thereto and carrying a squeegee holding bar including at least one blade depending therefrom for contact with the screen, the improvement comprising: mounting plates on each side of the squeegee drive bar extending downwardly toward said screen, aligned circular openings within respective plates, a rotatable cylindrical adjustment knob carried within each opening and means carried by each knob for coupling respective ends of said squeegee holding bar to said cylindrical adjustment knobs at points eccentric of the knob axis; whereby independent rotation of either knob effects simultaneous two-dimensional shifting of the squeegee holding bar pivot axis.

Claim 7

In a screen printing machine including a table carrying a blank to be printed and a screen overlying the same and a squeegee drive bar horizontally movable across the table and parallel thereto and carrying a squeegee holding bar including at least one blade depending therefrom for contact with the screen, the improvement comprising: mounting plates on each side of the squeegee drive bar extending downwardly toward said screen, aligned circular openings within respective plates, a rotatable cylindrical adjustment knob carried within each opening and means carried by each knob for coupling respective ends of said squeegee holding bar to said cylindrical adjustment knobs at points eccentric of the knob axis; whereby independent rotation of either knob effects simultaneous two-dimensional shifting of the squeegee holding bar pivot axis.

Claim 8

The screen printing machine as claimed in claim 9, wherein said means rotatably couple said blade holder at its end to respective cylindrical adjustment knobs comprising pins eccentrically carried by each cylindrical adjustment knob and axially aligned recesses within opposite ends of said squeegee holding bar to define the pivot axis of the same and receiving said eccentrically positioned pins.

Claim 9

The screen printing machine as claimed in claim 5 wherein said squeegee holding bar includes, at each end, aligned cylindrical holes extending partially along the direction of the major axis of said bar, and each rotatable adjustment knob carries eccentrically positioned cylindrical extensions with said cylindrical extensions received within the cylindrical holes of said squeegee holding bar.

Claim 10

The screen printing machine as claimed in claim 7 wherein said cylindrical extensions are longitudinally curved to effect line contact between the eccentric extensions and the cylindrical holes receiving the same to facilitate individual adjustment of the support bar pivot axis at each end of the squeegee holding bar.

Claim 11

In a screen printing machine including a table carrying a blank to be printed and a screen overlying the same and a squeegee drive bar horizontally movable across the table and parallel thereto and carrying a squeegee holding bar including at least one blade depending therefrom for contact with the screen, the improvement comprising: mounting plates on each side of the squeegee drive bar extending downwardly toward said screen, aligned circular openings within respective plates, a rotatable cylindrical adjustment knob carried within each opening and means said cylindrical adjustment knobs to define a pivot axis for said squeegee holding bar eccentric to the axis of said aligned adjustment knobs; whereby independent rotation of said knobs effects simultaneous two-dimensional shifting of the squeegee holding bar pivot axis, said sqUeegee holding bar being further provided with a longitudinally extending keyway slot inclined with respect to the plane of said screen, said keyway slot having its side wall nearest the screen provided with angled, keyway surfaces and having a flat opposite side wall, and wherein said blade is carried by a slotted blade holder, said blade holder having keyway grooves within the sides of the same on the end opposite that carrying said blade, said keyway grooves interfitting with said keyway surfaces of said slot, and at least one adjustable clamping member carried by said squeegee holding bar for contact with said keyway groove facing said flat side wall after insertion of said blade holder therein and constituting the only means for holding said blade holder within said slot when the blade is out of contact with the screen.

Claim 12

In a screen printing machine including a table carrying a blank to be printed and a screen overlying the same and a squeegee drive bar horizontally movable across the table and parallel thereto and carrying a squeegee holding bar including at least one blade depending therefrom for contact with the screen, the improvement comprising: mounting plates on each side of the squeegee drive bar extending downwardly toward said screen, aligned circular openings within respective plates, a rotatable cylindrical adjustment knob carried within each opening and means said cylindrical adjustment knobs to define a pivot axis for said squeegee holding bar eccentric to the axis of said aligned adjustment knobs; whereby independent rotation of said knobs effects simultaneous two-dimensional shifting of the squeegee holding bar pivot axis, said sqUeegee holding bar being further provided with a longitudinally extending keyway slot inclined with respect to the plane of said screen, said keyway slot having its side wall nearest the screen provided with angled, keyway surfaces and having a flat opposite side wall, and wherein said blade is carried by a slotted blade holder, said blade holder having keyway grooves within the sides of the same on the end opposite that carrying said blade, said keyway grooves interfitting with said keyway surfaces of said slot, and at least one adjustable clamping member carried by said squeegee holding bar for contact with said keyway groove facing said flat side wall after insertion of said blade holder therein and constituting the only means for holding said blade holder within said slot when the blade is out of contact with the screen.

Claim 13

The screen printing machine as claimed in claim 9 wherein said blade holder is symmetrical and includes narrow pressure point protruding ridges extending longitudinally along both sides thereof, intermediate of its ends, for contact with the flat side wall of said keyway slot, said ridges constituting the sole areas of application of pressure to the side of said slotted blade holder facing said flat side wall; whereby, when said blade is pressed against said screen, the reaction force tends to pressure the diagonally opposite keyway surfaces.

Claim 14

In a screen printing machine including a table, a blank to be printed carried by said table, and a screen overlying the same, and a squeegee holding bar positioned for movement across said screen and parallel thereto, the improvement comprising: a keyway slot carried by said holding bar facing said screen and inclined with respect thereto, the side wall of the slot nearest the screen including angled keyway surfaces and including a flat opposite side wall, a blade holder including keyway grooves carried on opposite sides thereof adjacent the inserted end for interfitting contact with the keyway surfaces of said slot, and at least one adjustable clamping member carried by said squeegee holding bar for contact with the keyway groove of said holder facing the flattened side wall of said holding bar slot after blade holder insertion and constituting the only means for holding said blade holder within the slot when the blade is out of contact with said screen.

Claim 15

In a screen printing machine including a table, a blank to be printed carried by said table, and a screen overlying the same, and a squeegee holding bar positioned for movement across said screen and parallel thereto, the improvement comprising: a keyway slot carried by said holding bar facing said screen and inclined with respect thereto, the side wall of the slot nearest the screen including angled keyway surfaces and including a flat opposite side wall, a blade holder including keyway grooves carried on opposite sides thereof adjacent the inserted end for interfitting contact with the keyway surfaces of said slot, and at least one adjustable clamping member carried by said squeegee holding bar for contact with the keyway groove of said holder facing the flattened side wall of said holding bar slot after blade holder insertion and constituting the only means for holding said blade holder within the slot when the blade is out of contact with said screen.

Claim 16

The screen printing machine as claimed in claim 11, wherein said blade holder is symmetrical in cross sectional configuration and includes longitudinally extending pressure point protruding ridges along each side of said holder intermediate of its ends for contact with the flat side wall of the blade holder slot after insertion therein, said ridges constituting the sole area of application of pressure to the side of said slotted blade holder facing said flat side wall, whereby; the reaction force, due to contact between the blade and the screen acting on the ridge pressurizes the diagonally opposite keyway surfaces.