EXTERNAL CONTROL DEVICE FOR VARIABLE DISPLACEMENT COMPRESSOR

PURPOSE:To improve running performance during the adjustment of height and the operating performance of a height adjusting device as the essential function of a variable displacement compressor is utilized by properly controlling the capacity or the variable displacement compressor from the outside according to the state of an engine load. CONSTITUTION:During the normal operation in which the adjustment of a height is unnecessary, and a hydraulic pressure generating source 104 for adjusting the ground clearance is not operated, the bypass quantity of a refrigerant toward an intake side in the compression stroke of a compressor 2 forming an air conditioning device is adjusted by a variable capacity mechanism 50 to perform cooling operation effectively. On the other hand, when the adjustment of the height is required, and the actuation of the hydraulic pressure generating source 104 has been therefore done, a detecting means 106 for the adjustment of the ground clearance detects the actuation, and then a capacity control means 110 causes a bypass passage 39 to fully open to control the minimum capacity setting mechanism SV so as to make the compressor 2 attain to the minimum discharge capacity. A load for the compressor 2 can be therefore reduced to distribute an engine output to the hydraulic pressure generating source 104.