GB1434220A - Photocopying machines and apparatus - Google Patents

Abstract

1434220 Electro-photographic apparatus RICOH KK 30 July 1973 [31 July 1972 (2) 3 Aug 1972 (2)] 36102/73 Heading G2H The length of electro-photographic copying material 2 supported on the peripheral surface of a drum 1 of a copying apparatus is periodically changed as the material becomes worn by driving a take-up reel 4 mounted inside the drum so that a fresh length of material is drawn from a feed reel 6 also mounted inside the drum. The drive means for the take-up reel is mounted outside the drum and preferably comprises a main drive gear 55 for rotating a shaft 3 and the drum 1 and being itself driven from a chain 70 through a gear 51, a transmission gear 57 driven by gear 55 and connected to a connection gear 61 through a solenoid operated spring clutch, a sun gear 68 arranged to be driven by the connection gear and mounted for free rotation about shaft 3 and a take-up reel advancing gear 69 meshing with the sun gear. The arrangement is such that with the spring clutch disengaged the gear 69 is not rotated by the sun gear but with the clutch engaged (by actuation of solenoid M) the clutch is engaged and the sun gear is rotated to drive the gear 69 and thus the take-up reel. The chain 70 also oscillates a pawl 78 which advances a ratchet 73 by one tooth for every rotation of the drum 1 (i.e. each cycle). After a predetermined number of copies has been made the solenoid M is energized to transmit drive to the take-up reel. A solenoid M, is also energized to release a control member 72 for rotation with ratchet 73. This control member actuates a pawl 93 to move a ratchet 92 by one tooth when a fresh length of copy material has been driven into place. The control member then actuates a switch S, to de-energize solenoids M and M 1 and so disable the drive to the take-up reel. The movement of ratchet 92 is indicated on a dial 100 by a pointer 99 so that the number of lengths of copy material remaining on the supply reel is indicated. Every time the control member 72 is actuated the switch S 1 waves for a different position around the periphery of the control member to compensate for the effective increase in size of the take-up reel (and thus the amount of material taken up per revolutions) as the copy material is wound thereon. When the supply of copy material is exhausted a switch S 2 is actuated to activate an alarm.