GB1011936A - Device for the control of a roll of paper exposure installation - Google Patents

Abstract

1,011,936. Feeding webs. PENTAGON DRESDENUND KINOWERKE DRESDEN VEB. July 30, 1963, No.30178/63. Heading B6B. [Also in Division G2] The paper-advancing mechanism in a photocopying apparatus comprises a lever having a toothed segment which is coupled by gearing to a transport drum, the lever being actuated by an arm thereof which bears against a cam, the camshaft also controlling a switch to shut off the driving motor. In the form shown, the toothed sector 3 is journalled to the main housing, and biased clockwise by a spring 2. On being turned anti-clockwise, it engages with gearing 35, 37 and so operates drum 38 which feeds the photo-sensitive paper strip 39 across the exposure aperture 40. An integral arm extending from sector 3 has at its lower end a wheel 4, which is caused by biasing spring 2 to bear against one of a series of differently-sized cams 5, 6, 7 mounted on a hollow shaft 10. Shaft 10 can slide on a spindle 11, and by operating a pinion 12 a selected one of the cams can be brought into engagement with wheel 4, by this means altering the length of paper advance. The shape of the cams is such that the acceleration and deceleration of the paper movement is sinusoidal, and each has a fairly wide " rest '' position (Fig. 2, not shown) so that even if the cam rotates a little further as the switched-off motor runs down, no further movement is imparted to the wheel 4, and hence the papermoving sector 3. Spindle 11 also carries contact discs 22, 23 which engage with blades 24, 25 of a switch in the circuit of the drive motor 21. The operation of the machine is started by closing switch 59. An image of the film 32 is projected so as to be reflected by a hinged inclined mirror 31 on to a ground glass inspection plate 34. Switch 57 is now closed, which causes mirror 31 to swing to a vertical position, allowing the projected image to fall on the paper 39 and so effect the exposure. Mirror 31 now pivots back into its inclined position, during which movement it actuates switch 29, so starting motor 21. This is geared to spindle 11, and so drives cam 5, 6 or 7 to operate the paper advance. After one full revolution of spindle 11 motor 21 is switched off by the action of contact disc 22 on switch blade 24. The action of contact disc 23 on switch blade 25 now energizes motor 48 which controls a paper-cutting operation via cam disc 44 and lever 43; a knife 42 on a pivoting plate 41 cuts off the end section of paper strip 39. After one rotation of cam disc 44, motor 48 is also switched off.