| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a toner quantity detecting device which makes optical detecting by using photocouplers which enable steady detection of toner concentration over a long period of time. <P>SOLUTION: In the toner quantity detecting device, a shutter blade 92 which can be opened/closes is provided in front of the photocouplers (PA, PB). The shutter is provided with a reflecting member 93 which moves integrally or together with the shutter. Adjustment control is exerted so that a sensor output becomes a predetermined value, by using the light reflected from the reflecting member 93 with the shutter closed. Thereafter, the shutter is opened to detect the quantity of the toner. <P>COPYRIGHT: (C)2004,JPO |
