| 摘要 |
An optical transducer for indicating the angular position of a rotating body with respect to a fixed structure comprising a housing 25, 26 of plastics mateial inside which a rigid disc 12 is rotatably mounted, this disc being connected to the rotating body and being provided with radial slots 36 arranged in two concentric annular tracks. At a position corresponding to the slots in the disc, the outer walls of the housing have seats 53, 54 provided in them during the moulding operation and these receive, in a detachable manner, a series of light sources 54 provided on one side, and on other side a corresponding series of light detector devices 56. In order to provide light beams which are orthogonal to the plane of the disc, windows 62, 63 having dimensions which are substantially equal to those of the radial slots 36 in the disc are formed in the housing at positions corresponding to those of the light sources and light detector devices. The periphery of the disc is furthermore provided with teeth 40 which partially extend outside the housing, a positioning mechanism 41 for the rotating body being adapted to cooperate with the teeth. |
