Patent ID: 6639238
Filing Date: 2003-10-28
Classification: B41J,G01V,G03G

Abstract:
A photo interrupter with dual-direction detection ability, comprising:main body for detecting light interruption and having a light emitter, a light receiver, a recess between the light emitter and the light receiver, and two retainers respectively disposed on both sides of the recess; a pointer having two rotational pivots respectively disposed on both sides thereof and pivotally arranged on the retainers, the pointer having a baffle on a front end thereof and a pendulum end on a rear end thereof, wherein the baffle is placed in the recess; a first spring looped on the rotational pivot on one side of the pointer and having a movable end disposed on the main body and a fixed end clamped in the pointer, the first spring providing a first predetermined torque in a first direction; a second spring looped on the rotational pivot on another side of the pointer and having a movable end disposed on the main body and a fixed end clamped in the pointer, the second spring providing a second predetermined torque in a second direction, the second direction being opposite the first direction and the second predetermined torque being different than the first predetermined torque.