Patent GB-925248-A (GB)
Title: Duplicating machine
Inventor: SPRINGER EDWARD MICHAEL
IPC: B41L19/00
Filed: 1961-03-13
Abstract: 925,248. Feeding sheets. HEYER Inc. March 13, 1961, No. 9072/61. Class 100 (1). A duplicating machine comprises a support for copy sheets, a rotatable drum for carrying a master, means for feeding copy sheets successively from the support through the machine, an electric motor for driving the feed means and drum, an electric circuit for controlling the motor, the machine operating through a succession of cycles in each of which one copy sheet is fed through the machine, means responsive to the exhaustion of the pile of sheets on the support, and means actuated by said responsive means for de-energizing the circuit and stopping the motor. Copy sheets 20, Figs. 1 and 6, are fed in succession from the top of a stack on a support 22 by feed rollers 74 through a passage 78 between baffles 76 to the nip between a driven moistening roller 42 and idler roller 44, and thence to the printing drum 36 and impression roller 40, each roller drive being discontinued and the rollers free-wheeling after the sheet has reached the following drive nip. The rollers 74, 44 and the drum 36 are driven by an electric motor 102. The rollers 74 are mounted on a shaft 72 carried on side arms 86 pivoted at 92, the rollers 74 resting on the sheet pile by gravity. When no sheet is present the rollers fall into depressions 82. One arm 86 has an extension 294, Fig. 18, having pivoted thereto at 300 an arm 298 having a part formed with a cam surface 308 and a lower face 309 which is supported by a pin 292 on a pivoted starter arm 260 to hold the rollers 74 in there top position. The drum shaft 132, Figs. 6 and 8, is connected to a coaxial shaft 114, Fig. 9, provided with a brake 196 applied when a solenoid 214 is energized, and latched by a lever 228. Pressing a button 262 moves the arm 260 to release the feed mechanism from the pin 292 and to actuate a start switch for the motor and release the latch lever 228 to take off the brake. While the machine is operating and the rollers 74 descend, the pin 292 rides up the side of the arm 298. When the rollers fall into the depressions 82, the pin 192 enters a recess 314 to release the arm 260. When the rollers 74 are in the depressions or in their uppermost position, a roller 358, Fig. 8, enters a low point 354 or 352 of a cam arm 346 secured to one of the arms 86, and a cam on the drum acts, at a particular angular position of the drum, on a roller 374 or 378 and through a linkage 360, 318, 336 closes a switch 342 to energize the solenoid 214 to stop the motor and apply the brake. The drum can be stopped in either of two angular positions according to the copy sheet length, by setting a slide 400 by a button 410 to position the selected one of the rollers 374, 378 in the path of the cam on the drum. Before replenishment of the sheet stack, the arms 86 are raised by means of a bar 90, the pin 292 camming the arm 298 outwards until it passes below the surface 309. The roller 374 (for long sheets) may be replaced by a trip arm engaged by a trip element stationary with respect to the drum shaft. For single cycle operation, a button 426 causes a latch 419 to hold the feed means in its uppermost position so that the motor is stopped after each cycle. A button 426 can be used to release the brake without re-starting the machine.