PURPOSE: To easily provide a shaft seal device to meet the purpose of the use without executing the surface working on a rotary shaft by providing a first shaft seal device arranged on the outer circumferential part of the rotary shaft, and a second shaft seal device which is provided between the first shaft seal device and the rotary shaft, and driven by the rotary shaft.

CONSTITUTION: In a compressor to be used for the refrigeration cycle, a plurality of pistons 23 are reciprocatingly slid with the time difference in a cylinder 40, and the fluid such as a gaseous refrigerant in a suction chamber 32 is discharged in a discharge chamber 33 by swaying a swaying plate 19 around a rigid ball 21 along the inclined surface of a rotor 24. The sealing between a rotary main shaft 2 and a boss part 1 of a front housing 10b is realized by a lip seal 11 which is a first shaft seal device. An auxiliary shaft seal device 26 provided with a hollow part where the rotary main shaft 2 is penetrated, and a thick wall part 26a for fixing the shaft on one end is provided as a second shaft seal device through an O-ring, and the second seal shaft device is driven by the rotary main shaft 2.