| 摘要 |
PURPOSE:To enhance detection reliability by smoothing the rotation of a rotor, by providing the coil spring provided between the rotor and a casing to the outer periphery of the rotor so as not to allow the same to slide with the outer surface of a shaft support part as possible. CONSTITUTION:A rotary position detection apparatus having a spring 2 for return rotation is equipped with a lever 3, a cashing 4, a rotor 5, a bearing 6, a substrate 7 and a brush contact 8. When the rotor 5 rotates with the rotation of a body to be detected, the rotor 5 rotates while involves the spring 2 and also rotates by the unwinding force of the spring 2. At this time, one end part 22 of both end parts of the spring 2 is supported by a casing side guide part 4a in a closely contacted state and the other end part 23 thereof is supported by a lever side guide part 3a in a closely contacted state but the central part 21 of the spring 2 other than both ends thereof surrounds the rotor 5 so as to be separate by a predetermined space from the outer surface of the shaft support part 4d integrated with the casing 4. Therefore, because the central part 21 is not contacted with any part at the time of rotation, torque of return rotation is obtained by the smooth rotation of the rotor 5 and the stable spring 2.
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