Variable displacement swash plate type compressor

A variable displacement swash plate type compressor comprising:

• a casing having a bore, a suction chamber, a discharge chamber, and a crankcase;
• a rotating shaft which is supported rotatably on the casing;
• a swash plate which is rotated within the crankcase in conjunction with the rotating shaft;
• a piston which reciprocates within the bore in conjunction with the swash plate and forms, together with the bore, a compression chamber;
• and
• an inclination adjustment mechanism which has a first flow path which communicates the discharge chamber with the crankcase, and a second flow path which communicates the crankcase with the suction chamber, in order to adjust an inclination angle of the swash plate with respect to the rotating shaft,
• wherein, in the second flow path, an orifice hole which decompresses a fluid passing through the second flow path, and an orifice control mechanism which controls an effective flow cross-sectional area of the orifice hole are formed,
• wherein, the orifice hole and the orifice control mechanism are formed such that when a differential pressure between a pressure in the crankcase and a pressure in the suction chamber is increased, the effective flow cross-sectional area changes from zero to a first area that is larger than zero and when the differential pressure is further increased, the effective flow cross-sectional area becomes a second area that is larger than zero and less than the first area,
• wherein the orifice hole comprises a first orifice hole which is in communication with the crankcase, a third orifice hole which is in communication with the suction chamber, and a second orifice hole which is formed between the first orifice hole and the third orifice hole,
• wherein the orifice control mechanism comprises a valve chamber which is in communication with the first orifice hole and the second orifice hole, and a valve core which reciprocates along the valve chamber and controls an opening amount of the first orifice hole, an opening amount of the second orifice hole, and an opening amount of the third orifice hole,
• wherein the valve chamber comprises a valve chamber inner circumferential surface which guides the reciprocating motion of the valve core, a valve chamber first front end surface which is located at one end side of the valve chamber inner circumferential surface, and a valve chamber second front end surface which is located at the other end side of the valve chamber inner circumferential surface,
• wherein the first orifice hole is in communication with the valve chamber at the valve chamber first front end surface,
• wherein the second orifice hole is in communication with the valve chamber at the valve chamber second front end surface,
• and wherein the third orifice hole is in communication with the second orifice hole at a position facing the valve chamber, so that the first orifice hole, the valve chamber, the second orifice hole, and the third orifice hole are formed sequentially according to a direction of the reciprocating motion of the valve core.