GB435376A - Method and apparatus for decorating surfaces - Google Patents

Abstract

435,376. Printing-machines. OXVAR, Ltd., 3, Lower Regent Street, London.- (Assignees of Casto, L. V.; 4084, West Philadelphia Avenue, Detroit, Michigan, U.S.A.) May 20, 1935, No. 14659. Convention date, June 14, 1934. [Class 100 (ii)] Rotary machines; printing on curved surfaces; tripping-arrangements.-A method of surfacedecorating objects having straight and curved surfaces comprises passing the object between a printing-roll and a pressure roll and varying the rate of movement of the object as it is being printed, whereby the straight surfaces of the object are printed at one speed and the curved surfaces of the object are printed at a different speed. Articles W, Fig. 1, such as frames and boxes having straight surfaces joined by curved surfaces are decorated with wood grains and other patterns by passing them between a pressure roll 13 and a transfer roll 12 which are both driven by gearing from a speed-reduction gear unit 73 which is driven by a motor 70 through a speed-changing gear unit 71. The unit 71 is manually operated so that when the curved surfaces are to be printed the speed of the rolls 12, 13 is reduced. The transfer roll 12, as shown, receives ink &c. impressions from an intaglio pattern roll 10, but the transfer roll is not essential. The rolls 10, 12 are supported on a base 6, the shaft ends of the roll 12 being eccentric whereby on turning a knob 27 the pressure between the two rolls may be adjusted. The lower end of the shaft 17 of the roll 10 has a spigot connection with an extension on which are mounted two bevel gears 78, 90, the gear 78 being driven from a shaft which is driven by chain and sprocket means direct from the reduction unit 73, and the other gear 90 driving a shaft 62 from which, by bevel gears 93, 94, the pressure roll 13 is driven. The pressure roll 13 is adjustable towards the roll 12 by means of a handle-operated screw shaft 63 with which a screwed bearing bracket 61 of the roll engages. The rolls 10, 12 are connected by a pivoted arm 19, and are geared together by gear rings 85, 86 on their upper ends. The speed-changing device 71 is preferably integral with the frame of the motor 70, and comprises a short hollow shaft, constantly driven by gears from the motor shaft, which has loosely mounted thereon a number of gears which mesh with similar gears on a shaft which is in alignment with the motor shaft, and which is coupled by a coupling 140 to the shaft 72 of the reduction unit 73. A member is movable along the inside of the hollow shaft to clutch any of the gears to the shaft, by depressing a pivoted control lever 155 which actuates the member by segmental rack-and-pinion means 157, 153. In a modification shown in Fig. 3, the bracket 61 of the pressure roll 13 is slidable along a shaft 63a for adjustment towards the roll 12, and is connected at two opposite sides to weights 170, 184. The weight 184, tending to pull the roll 13 towards the roll 12, is greater than the weight 170, and is supported on a block 190. The block 190 rests on a compression spring 191 supported on a bracket on the machine, and is connected by a link to a pivoted control lever 155a of the speed-changing unit, so that when the lever 155a is depressed, the weight 184 is allowed to fall to pull the roll 13 towards the roll 12. When the roll 13 engages the workpiece, the extension 200 of the control lever 155a engages a pin on a segmental rack 157a which operates the clutch member inside the hollow shaft of the speed-changing unit. The speed-changing unit in both constructions runs idly until the control lever is depressed. Inking-apparatus; set-off, preventing.-The roll 10 is supplied with ink or colour from a well by means of a vertical screw driven from the roll 10 and discharging ink through a slot in the casing surrounding the screw, the casing being adjustable towards the roll 10. The rolls 10, 12 are scraped by doctors which are both mounted pivotally on one supporting bar, and connected together at their ends beyond the pivot by a spring which presses them into contact with their respective rolls. Specification No. 392,384 is referred to.