JPS57122458A - Scanner in copying machine - Google Patents

Abstract

PURPOSE:To obtain a device which is simple to change scanning distances and of which moving parts are light in weight with respect to a mangle mechanism performing lens driving. CONSTITUTION:If an effective linear distance is defined as l1 in the case of narrow scanning width, this is the length of the rack teeth combining mangle racks 1, 2. As a motor 21 runs, a timing pulley 20 turns in an arrow direction, and a pulley 10 turns simultaneously as well. A pinion gear 3 is turned, and a slide 13 is guided by guide rods 16, 17 and moves closer to the side of the motor 21. An arm 23 for extension is turned in the direction (b). Further, when the gear 3 is turned to complete the shifting of the turned l1, it meshes with the tooth profile in the curved part of the rack 1. During this time, the guide roller rotated and moved in contact with the bottom surface of a guide plate 38 moves along the curved surface of the guide plate along with the rotating movement of a shaft 4, and passes the curved part integrally with the meshing of the gear 3 with the internal teeth of the rack 1. In this way, the required movement is transmitted to the slide 13.