Ambient light and dust protection for a mechanically operated optical switch

摘要

An optical switch operating mechanism including a housing cooperatively preventing dust and light from easily reaching an optical switch supported within the housing. The housing includes integrally formed spaced apart slots for receiving the optical switch and an associated integrally formed tubular shaft for slidably receiving a switch operator, a portion of which extends outside the housing. The tubular shaft is positioned between the spaced apart slots such that the longitudinal axes of the shaft and it's associated pair of slots and are perpendicular to one another. A light passage, also integrally formed with the pair of slots and associated shaft, passes through the shaft connecting the associated pair of slots such that light from the optical switch emitter can be received by the optical switch receiver when a window in the switch operator is aligned with the light passage. The snug fit of the switch operator in the tubular shaft combined with the perpendicular alignment of the light passages with the shaft prevents any light or dust which might fall on that portion of the housing from which the switch operator extends from having a direct path to the optical switch. A circumferential flange integrally formed from an enclosed end of the switch operator and snugly received within an integrally formed extension of the housing prevents light and dust entering through an actuator access aperture in the housing from reaching the optical switch.