| 摘要 |
PURPOSE:To make compact a DC motor driver by providing a pulse modulator producing a pulse corresponding to a torque command signal, a Hall effect element corresponding to an exciting coil onto which a pulse signal is applied from the pulse modulator, and a power amplifier for amplifying an output from the Hall effect element and applying onto the exciting coil. CONSTITUTION:A torque command signal is fed from an input terminal 1 through an absolute value circuit 6 to a pulse width modulator 3. Pulse output from the pulse width modulator 3 is fed through a direction switch 7 to Hall effect elements 2a-2c corresponding with exciting coils 5a-5c. Outputs from the Hall-effect elements 2a-2c are applied onto power amplifiers 4a-4c corresponding with the exciting coils 5a-5c. At the same time, polarity of torque command signal being applied on the input terminal 1 is decided through a polarity decision circuit 8 and the direction switch 7 is switched depending on the decision result. Consequently, the number of necessary pulse width modulator and associated absolute value circuit, polarity decision circuit, and direction switching circuit can be set, respectively, at once. |
