| 摘要 |
PROBLEM TO BE SOLVED: To improve the durability of a thrust bearing and reduce the power loss by regulating the pressure of a crank chamber according to the sliding quantity of a drive shaft, and controlling the relation of the pressure of a cylinder bore with the pressure of the crank chamber so as to keep the average value of the thrust fluctuating load at zero. SOLUTION: In a single head reciprocating fixed displacement type compressor, an axially forward thrust fluctuating load acts on a drive shaft 16 through a piston 35 and a swash plate 31 according to the intermittent compressing motion of coolant gas, and the load is received by a thrust bearing 32. On the other hand, the blowby from a cylinder bore 33 or a high-pressure coolant gas passed through feed passages 18, 12a, 44 is supplied to a crank chamber 15, and its pressure works an axially backward thrust load to the drive shaft 16. The relation of the pressure of the cylinder bore 33 with the pressure of the crank chamber 15 is controlled by a control valve device 46 having a valve part 47 so as to keep the average value of the thrust fluctuating load at zero. |
