Abstract:
The present invention provides a power window apparatus that, even if a CPU (IC2) causes malfunction or becomes uncontrollable upon submergence, can prevent windows from performing unexpected operations and enables the windows to be opened without fail if desired. The power window apparatus comprises: a driving part that has two current input-output ends, and opens or closes automobile open/close parts, depending on the direction of a flowing current; two relays which respectively have exciting coils and switching contacts, wherein, when a current is fed to the exciting coils, the switching contacts connect the current input-output end to a positive or negative pole of power; a submergence detecting sensor that drops in resistance value between both ends thereof when exposed to water; and a submergence-time escape switch that forcibly drives the open/close parts open upon submergence, wherein transistors are provided which are connected in series with the exciting coils and feed a current to the exciting coils, and the bases of the transistors are grounded via the submergence detecting sensor.
Abstract:
Disclosed is a motor control circuit having a motor protective circuit of a simple configuration having a small number of cheap component parts. A motor control circuit has: a current detecting resistor connected to a motor in series; a series circuit of an operation switch, a switching device, and a relay winding connected between a power source and a reference potential point; a bias circuit including a temperature dependent resistor for supplying a bias voltage to the switching device; a switching state self-holding circuit including an automatic operation switch; and an overvoltage detecting circuit. When the operation switch is switched on or when the operation switch and the automatic operation switch are simultaneously switched on, the switching device is switched on to energize the relay winding and a contact in the relay is switched to drive the motor. When an overcurrent is passed to the current detecting resistor and a temperature rise in the current detecting resistor is detected by the temperature dependent resistor and/or when a rise in a voltage across terminals of the current detecting resistor is detected by the overvoltage detecting circuit at the time of driving the motor, the switching device is switched off via the bias circuit to thereby stop the driving of the motor.