| 摘要 |
PURPOSE:To enable a stepping motor to be driven even when a coil winding is disconnected by providing a stepping motor driving section with each coil winding having each inversion phase and controlling the inversion phase of this winding and the rest of the coil winding when the coil winding is disconnected. CONSTITUTION:When A and B phase excitation signals EA and EB (H signals) are output from a driving controller at normal state of coil winding, A and B phases are excited to an S pole and subsequently two phases are excited to an A pole and subsequently two phases are excited like (B, A')... and then a motor is driven. When A' phase coil winding 61A' is disconnected, an A' phase disconnection sensing signal DA' is set to an L signal. In this case, when A' phase excitation signal EA' is output, a current direction switching signal CAA' is switched to H. Therefore, reverse current Ia flows to A phase coil winding 61A and the A phase is excited to an N pole. Since the A phase is the inversion phase of the A' phase, the A phase plays the part of the A' phase and the motor is driven without any hindrance. As a result, even when another coil winding is disconnected, the motor is driven in the same way. |
