| 摘要 |
PURPOSE:To prevent destruction caused by motor locking and to reduce the size and weight of the device, by permitting an actuator that drives a temperature control plate with a positive and negative rotation motor to contain in itself a maximum position detecting switch to cut a current at the maximum cooling and heating positons. CONSTITUTION:Signal voltage Vi from a detecting section lies between the setting voltage VC and VH during cooling/heating process. When fresh air temperature or room temperature drops to cuase the relation. Vi>VH while an air mixing damper 12 stops at point A, a comparator 16 is actuated to turn a relay 24 on. The actuator 3 shifts the damper 12 to the HOT side and at the same time it also decreases a resistance value of a potentiometer 5, so that the Vi also decreases and the actuator stops at a position B where the relation VH>= Vi>=VC is applicable. Otherwise, the relay 24 on the HOT side keeps an on- state, but electrodes 15a and 15b of the maximum position detecting switch are turned off causing the current to a motor to be cut off so that the motor may not be locked even at the time of the maximum heating. |
