| 摘要 |
PURPOSE:To provide a temperature controlling system for automotive air conditioner, which is capable of keeping a desired temperature, by detecting the temperature change of suction air at the point after cooler and compensating the control characteristics of control circuit according to said temperature change. CONSTITUTION:Variable resistance 21 for determining a desired temperature is provided on the control panel in the cabin such that it can be operated by hand, Potentiometer 22 is interconnected with damper to transmit the motion of damper to the input of control circuit 23 by way of negative feedback. Temperature sensitive element 24 is used for detecting the temperature in the cabin, whereas temperature sensitive element 25 is used for detecting the atmospheric temperature. Here, thermistors having a negative characteristic are used for the above two temperature sensitive elements. In case that temperature in the cabin becomes lower than the desired set temperature, resistance of element 24 is increased to raise voltage V1 until it becomes larger than V2, and electromagnetic valve 13 is opened,thus increasing the negative pressure acted in diaphragm actuator, moving the damper to the high-temperature side, and increasing the heating rate of heater, whereby temperature of air diffused into the cabin is raised. However, if V2 becomes larger than V1 as resistance of potentiometer 22 is decreased with movemrnt of damper to the high-temperature side, valve 13 returns to its closed position. Thus, temperature of air in the cabin can be always kept at a desired temperature. |
