| 摘要 |
1,122,621. Feeding sheets. RANK XEROX Ltd. 2 Sept., 1965 [30 Sept., 1964], No. 37585/65. Heading B6B. A sheet registration device 45, described as applied to mechanism adapted to feed sheets to a printing drum in a xerographic apparatus, comprises front register stops 513 secured on the shaft 514 of one feed roller 511 which is driven and co-operates with an idler roller 512, which is biased towards the roller 511, the roller 511 being driven at a speed which varies cyclically by a shaft 517 which is freely mounted within the shaft 514 and is connected to the latter through a variablespeed drive. In this arrangement, the front stops 513 are rapidly advanced into the path of travel of a sheet, then rapidly retarded to effect alignment and registration of the sheet, and the two shafts are then driven at the same angular speed to cause the sheet to be fed towards the printing drum at a speed equivalent to the peripheral speed of the drum. The constantly-driven inner shaft 517, Fig. 2 and Figs. 3a to 3e (not shown), has secured thereon a drive arm 524 carrying a gear segment 523 which meshes with a gear segment 522 secured on the outer shaft 514, and a cam follower 525 on the segment 523 engages a fixed cam 526. The arm 524 is connected by a coil-spring 527 to the gear 522, so that the follower 525 is biased towards the cam 526. The shape of the cam 526 determines the speed variation between the two shafts 514, 517. The idler roller 512 is mounted on a shaft 531 journalled in arms 532 which are rocked about a rod 533 by cams 515 secured on the outer shaft 514, whereby the two feed rollers are separated during registration of a sheet. Both the feed rollers comprise a series of discs. The inner shaft 517 is driven from a clutch sprocket 551 (Fig. 2) by means of a drive arm 530 which is secured to the shaft and has a bent end engaging an aperture in the sprocket. The registration device 45, which forms a unit with feed means which deliver a sheet from the printing drum to a fuser device, can be readily disconnected fron the drive sprocket 551, and the whole unit can be removed from the machine. The sheets are separated from the top of a stack and forwarded to the registration device 45. |
