| 摘要 |
PURPOSE:To protect an actuator more effectively by detecting the amount of heat to be produced in the actuator based on an input signal to the actuator and limiting the input signal according to the detection results. CONSTITUTION:Amount of heat produced in the coil of an actuator is calculated by means of a multiplier 10 and integrated in an integrator 11 thus calculating temperature rise rate of the coil. The calculation results are fed to a comparator 12. The comparator 12 produces an output 120 when thus calculated temperature rise rate exceeds a predetermined value. Since detection results appear at an output terminal 2 upon occurrence of overheated state, the detection results are employed in negative feedback to a drive circuit thus protecting the actuator against breakdown. |
