| 摘要 |
PURPOSE:To improve heating start performance and prevent fogging from occurring on a window by providing the damper switching control circuit of inside and outside switching dampers that open and close inside and outside air introduction ports provided in a ventilating duct. CONSTITUTION:Since a sensor 21 detects that the temperature within a car room is below a preset temperature and a relay coil 29 is excited and then a movable contact 25 is switched to the 25b side, a motor 23 starts rotation and an inside and outside air switching damper 5 is set from the 5b to 5a side. When a movable section 26f is separated from a contact 26c, the relay coil 29 is not excited and the rotation of the motor 23 is stopped. In this case, the damper 5 is stopped in 5c that simultaneously introduces air A inside a car room and air B outside it, the exhaust air amount outside the car room is small. Thus, the heating effect is improved and fogging is prevented from occurring on a window. Then, when the air temperature within the car room reaches a preset temperature, the motor 23 is rotated by the excitation of a coil 27 and the damper 5 is moved to the 5b side. Since the coil 27 is not excited and the motor stops its rotation, the damper 5 is set to the air B introduction position. |
