| 摘要 |
PURPOSE: To avoid an abuse caused by the heating of a driving transistor while the power consumption is reduced. CONSTITUTION: First and second stepping motors 12 and 14 which transmit power to a driven part 10 with a rated driving output corresponding to the load torque of the driven part, first and second motor driving control units 15 and 16 which supply power to the first and second stepping motors 12 and 14 and perform their driving control, a temperature detector 7 which detects the heating temperatures of the respective motor driving control units 15 and 16 and an allocation function which allocates one of the first and second stepping motors 12 and 14 as a main driving unit and allocates the other as an auxiliary driving unit are provided. Further, an exchanging function which exchanges the allocation of the main driving unit and the auxiliary driving unit when it is decided that the temperature of the first or second motor driving control unit 15 or 16 exceeds a predetermined reference temperature is provided. |
