Toner level detector for developing unit of photocopier, facsimile, printer, providing sensor signals changing according to changes in toner amount

摘要

Toner level detector has light path creating unit, a reflector (58), projecting from one wall of toner container into interior of container. Light sensor continuously provides signals corresponding to amount of toner in light path. Light sensor (200) has light emitting unit (60) and light receiver (61) with reflector (58) to create light path. Reflector has transparent sections (66a,b) forming concave section (66) which protrudes into toner container. Section has reflective surface (67a) which reflects light from emitter (60) to transparent part (66a) of wall of recess. If toner is in light path, in concave section (66), then light is blocked or reduced according to amount of toner. Light passes through transparent part (66a), into transparent part (66b) of recess opposite light receiver (58b) and is reflected (67b) to light receiver (61). Light sensor emits output signal according to amount of light.