Drive control apparatus for electric actuator

摘要

In a drive control apparatus for an electric actuator to be activated under control of a changeover switch, the drive control apparatus including a power transistor arranged to supply therethrough the power to the electric actuator from an electric power source in response to operation of the changeover switch, a presumptive temperature of the power transistor is previously memorized and renewed in consideration with an increment of temperature change caused by consumption of the power when the electric actuator has been activated. The presumptive temperature is further renewed in consideration with a decrement of temperature change caused by lapse of time after the electric actuator has been deactivated. The power supply to the electric actuator is permitted only when the presumptive temperature is lower than a predetermined value. When the presumptive temperature becomes higher than the predetermined value, the power supply to the electric actuator is prohibited.