GB769707A - Improvements in sheet feeding devices for rotary duplicating and the like machines - Google Patents

Abstract

769,707. Feeding sheets. BLOCK & ANDERSON, Ltd. May 5, 1955 [June 1, 1954], No. 16247/54. Class 100(1) In a rotary duplicating machine, sheets are separated from a pile 4 by a pair of friction rollers 6 which always rest on the pile and are driven positively and continuously, each roller having a portion 19 of its cylindrical surface of rubber or other friction-producing material and the other portion 20 being smooth, and each top sheet of the pile is fed into the bight of a pair of intermittently-driven feed rollers 30, 31 which feed it to the printing drum 1 and impression roller 2. The separating rollers 6 are secured on a shaft 8 connected by chain-and-sprocket gearing to a counter shaft 10 which is driven by similar gearing from the shaft 34 of the drum 1. The feed roller 31, which is also a moistening roller, is driven intermittently by an oscillating gear segment which is operated by a cam on the shaft 34, substantially as described in Specification 682,842, this mechanism includes means for adjusting the length of the feed stroke of the gear segment so that accurate .register of the sheet and the drum 1 can be obtained during printing. The separating rollers 6 can be swung about the shaft 10 into, and retained in, an upper inoperative position. Friction pads 23 bear against the sheet pile 4 to prevent more than one sheet being separated therefrom at a time. The feed rollers 30, 31 pick up a sheet fed forward by the rollers 6 when the latter have finished their feed motion on the sheet.