摘要 |
A switch includes a substrate including a main body and a cylindrical portion protruding upright from the main body and defining a transverse groove in the outer surface thereof, a light emitter fixed on the cylindrical portion to receive light beams from the light emitter and produce three electrical outputs respectively, and a dial member including a cylindrical dial and two arms protruding upright from the cylindrical dial and forming two engagement portions on the inner surfaces thereof respectively. The engagement portions are engaged in the groove so that the cylindrical dial is rotatable to a number of orientations in which the produced electrical outputs are coded into a number of different switch signals by selectively blocking the radiated light beams using the two arms.
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