| 摘要 |
PURPOSE:To detect a fault mode due to the disconnection of wire or a short- circuit, etc., by providing slit-shape cut parts at plural positions in conductive patterns which constitute an encoder, and providing resistances which connect optional selected cut parts. CONSTITUTION:The encoder used for the rotation angle position detector for a motor consists of concentric conductive patterns 42 and 43, a power source pattern 44, and a contactor 45 which slides in contact with the patterns 42-44 while rotating synchronizing with the rotation of the motor. The patterns 42 and 43 are provided with slit-shape cut parts 42a and 42b, and 43a and 43b respectively, and the cut parts 42b and 43b are connected together by the resistance R. Electrodes A and B of the patterns 42 and 43 are grounded through resistances Ra and Rb and a power source E is connected to the electrode of a pattern C. The encoder is divided into four areas (c)-(f) and the potential when the contactor 45 is positioned in respective areas is set to a specific value by the values of resistances R, Ra, and Rb, and the power source E. Therefore, the potential of each area is measured to detect easily the separation, wire disconnection, short-circut, etc., of the contactor 45. |
