Cleaning device for drum of copying machine - has spiral spring to lift belt biassing cam clear of drum if current to drive motor fails

摘要

The drum (TR) of an electro-static copying machine is cleaned by a fabric belt (BA). The belt is unrolled from a spool (RI) and rolled onto a spool (R2) after passing round and guide pulley (AR). The spools and guide pulley are mounted on pivoted arm (ER) which is raised or lowered so that the belt touches the drum by means of a cam (NOS). The cam is driven by an electric motor (MO) but in the event of an electrical failure a spiral (SF) lifts the arms and it the pulley clear of the drum.