PURPOSE: To obtain the titled louver, temperature response thereof is excellent to a sudden heating-temperature change, by setting up thermostats to a bimetal driver and a body to be temperature-controlled and opening or closing a heater for driving a bimetal.

CONSTITUTION: The heater 8 is installed to a housing 7, the thermostats 91, 92 are each set up to an electronic apparatus 1 and the housing 7, and the heater 8 and the thermostats 91, 92 are connected in series and connected to a power supply 10. The heater 8 is opened or closed according to a predetermined method in response to the combination of the temperatures of the thermostats 91, 92. The thermostat 91 detects non-response of the bimetal even when the bimetal cannot respond to a temperature rise of T°C or more due to thermal resistance between the apparatus 1 and the bimetal 4 at that time, a response delay is detected by the thermostat 92 and the heater 8 is turned ON, and the opening of a blade 5 is increased and radiation efficiency is improved. The thermostat 92 is operated by a small time delay, and the heater 8 is turned OFF and the blade 5 is opened or closed. According to the constitution, the thermal louver of excellent temperature response is obtained.