MIXTURE COMPOSITION MONITOR

摘要

1292243 Weighing apparatus INTERNATIONAL BUSINESS MACHINES CORP 28 June 1971 [28 July 1970] 30105/71 Heading G1W [Also in Divisions G2-3] Electro-photographic developer comprising toner and carrier particles is fed through a tube 40 at such a rate that the tube is kept full of developer, and the weight of the tube of developer is used to monitor the rotation proportions of toner and carrier. As shown, tube 40 is pivoted at 63 by a system of wires Figs. 4 and 6 (not shown) and has a counterbalance arm bearing a counterweight 46. As toner is depleted the weight of the tube increases, the tube pivots downwards and a magnet 47 operates a toner replenishing switch 45. In Fig. 8 (not shown) the tube is pivoted on jewelled bearings. Arrangements are described for adjusting the biasing torque applied to the balancing system to select the density at which the developer must be held.