GB829284A - Improvements in or relating to rotary duplicating machines - Google Patents

Abstract

829,284. Stencilling-apparatus. RONEO Ltd. April 24, 1956 [May 2, 1955], No. 12691/55. Class 100(2) Stopping-arrangements. In a power operated rotary duplicating machine of the kind having a printing drum which supports a stencil sheet and contains a supply of ink which passes through perforations which extend partly round the surface of the drum and through the stencil sheet during the printing process, there is provided a variable speed gear which, on operating a lever, knob or the like to stop the machine, or after a preselected number of copies have been duplicated, or when only a few sheets of paper remain on the feedboard, automatically engages the lowest operating speed before the power is switched off, at a predetermined point in the cycle of operation of the machine. Operation of a lever 17, Figs. 2 and 3, to start the machine causes a slide 8, Figs. 1, 2 and 3, connected to a lever 6 to move to the left until a stud 31 on lever 6 abuts a lever 4, where it is held by a catch 5, the lever 4 being adjustable by a knob 26 to control the speed of the machine. The movement of the slide 8 causes a catch 16 to display a roller 20 on a lever 21, whereupon a screw 22 on the lever 21 depresses a switch button 7 to start the machine. Movement of the slide 8 also acts through a rod 15 on arms 12, 36 to regulate the transmission ratio between variable diameter pulleys 39, 14, the former being a drive pulley and the latter connected to the printing drum 1. As the slide 8 moves, a hook lever 11 when depressed by a cam 2 rotated by the drum is hooked under a catch plate 19, lever 11 moving up and down while the machine is operated. To stop the machine, a manual lever 48 is operated to trip the catch 5, or the latter is tripped mechanically after a preselected number of copies have been duplicated or when only a few sheets of paper remain on the feed board, releasing lever 8. The return speed of lever 8 is controlled through the rod 15 and arms 12, 36, which return through spring 44 and the machine load transmitted through the belt 13. The complete return of slide 8 is prevented by a plate 23 attached thereto contacting the lever 11, until the cam 2 moves the lever 11 again to its lowest position where it is free to disengage from the plate 19, at which time the slide 8 completes its return, and the plate 23 displaces the lever 11 to a position where at the top of the stroke of the lever 11 a plate 50 thereon is located above a lever 10. On the next descent of the lever 11, the plate 50 rotates the lever 10, which is fixed to a spindle 25, whereupon a lever 24 on the spindle is rotated to depress a switch button to stop the machine, before which time the drum 1 has been brought to its lowest speed. When the catch 5 is released, the sheet feeding mechanism is disengaged by a bell-crank 49. The drum makes one or more revolutions after the catch 5 is tripped, thereby ensuring that the last copy completely passes through the machine before the latter stops.