Piston type variable displacement compressor

A compressor having a refrigerant gas passage connected to a refrigerant circuit separately provided from the compressor, said compressor having a plurality of reciprocable pistons for compressing refrigerant gas, said compressor comprising:

• a housing having a refrigerant discharge chamber and a refrigerant suction chamber;
• a crank chamber disposed in the housing;
• a plurality of cylinder bores disposed in the housing, said cylinder bores communicating the discharge chamber and the suction chamber, and each of said cylinder bores accommodating one of the pistons;
• a drive shaft rotatably supported by the housing;
• a swash plate supported on the drive shaft for integral rotation with inclining motion with respect to the drive shaft in the crank chamber to drive the pistons, said swash plate being movable between a maximum inclined angle and a minimum inclined angle;
• disconnecting means for disconnecting the refrigerant circuit from the refrigerant gas passage when the swash plate is at the minimum inclined angle;
• and
• bleeding means for allowing the refrigerant gas to bleed from the refrigerant gas passage to the refrigerant circuit to avoid rapid increase of the inclined angle when the disconnecting means operates.

A compressor operated in accordance with operation conditions computed by a computer electrically connected to the compressor, and having a refrigerant gas passage connected to a refrigerant circuit separately provided from the compressor, said compressor having a plurality of reciprocable pistons for compressing refrigerant gas, said compressor comprising:

• a housing having a refrigerant discharge chamber and a refrigerant suction chamber;
• a crank chamber disposed in the housing;
• a plurality of said cylinder bores disposed in the housing, said cylinder bores communicating the discharge chamber and the suction chamber, and each of cylinder bores accommodating one of the pistons;
• a drive shaft rotatably supported by the housing;
• a swash plate supported on the drive shaft for integral rotation with inclining motion with respect to the drive shaft in the crank chamber to drive the pistons, said swash plate being movable between a maximum inclined angle and a minimum inclined angle;
• a first passage for connecting the crank chamber and the suction chamber to deliver the refrigerant gas from the crank chamber to the suction chamber;
• a second passage for connecting the discharge chamber and the crank chamber to deliver the refrigerant gas from the discharge chamber to the crank chamber;
• a suction passage for connecting the refrigerant circuit and the suction chamber for supplying the refrigerant gas from the refrigerant circuit to the suction chamber;
• a discharge port for connecting the discharge chamber and the refrigerant circuit for discharging the refrigerant gas from the discharge chamber to the refrigerant circuit;
• control means for controlling the drive the swash plate in accordance with electric signals indicative of the operating conditions of the swash plate, said computer outputting said electric signals;
• disconnecting means for disconnecting the refrigerant circuit from the refrigerant gas passage when the swash plate is at the minimum inclined angle;
• bleeding means for allowing the refrigerant gas to bleed from the refrigerant gas passage to the refrigerant circuit to avoid rapid increase of the inclined angle when the disconnecting means operates;
• and
• a circulating passage including the first passage and the second passage, said circulating passage being formed upon disconnection of the refrigerant circuit and the refrigerant gas passage.