| 摘要 |
PURPOSE:To make it possible to keep car room temperature constant by preventing the action of a thermoswitch circuit by a load detecting circuit when evaporator surface temperature is above the second set level in an air conditioner turning a compressor off when accelerating. CONSTITUTION:When a pressure switch 2 is turned on with acceleration, an operational amplifier 11 output becomes H to be supplied to an operational amplifier 20 of a timer circuit 4 as a trigger pulse, and thereby a pulse with the width T is supplied to the non-inverting input side of an operational amplifier 30 in a thermoswitch circuit 5 allowing its output to be saturated to an H level to turn the compressor off via a transistor 40. When evaporator surface temperature drastically rises in this way to reduce the resistance of a sensor 6, the output of an operational amplifier 44 changes to L to cause a diode 47 to be turned off to absorb the trigger pulse, thereby allowing the output of the timer circuit 4 to restore to the L. Hereby, the compressor is turned on via the transistor 40. Consequently, acceleration and slope-climbing are smoothly performed while car room temperature is rapidly cooled down. |
