| 摘要 |
PURPOSE:To suppress the overspeed of a motor by switching a quasi-encoder signal when an encoder signal is interrupted. CONSTITUTION:A quasi-encoder pulse generator 20 which contains a circuit for generating a quasi-encoder pulse and having a circuit for discriminating whether the encoder signal from a photoreceptor 6 is interrupted or not, and a gate 30 which selects the output signal of the photoreceptor 6 or the quasi-encoder pulse on the basis of the discriminated result of the generator 30 and outputting to a speed feedback circuit 2a. When the output signal of the encoder is stopped, the quasi-encoder signal output from the generator 30 is input to a motor controller. |
