Patent ID: 6837691

Claim:
A refrigeration suction mechanism used in a piston type compressor, wherein a cam member mounted on a rotary shaft for the integral rotation with the rotary shaft converts a rotation of the rotary shaft to a linear reciprocating movement of pistons in cylinder bores arranged around the rotary shaft, wherein a compression chamber is defined in each of the cylinder bores by the associated piston, and wherein refrigerant is introduced to, compressed, in and discharged from the compression chamber when the piston is in a suction stroke, a compressing stroke and a discharge stroke respectively, said compressor having a refrigerant passage for allowing the refrigerant to flow toward the compression chamber, said mechanism comprising: a rotary valve formed integrally with the rotary shaft, or fixed to the rotary shaft to be integral with the rotary shaft, said rotary valve including an introducing passage that is in communication with the refrigerant passage; suction passages, each corresponding to one of the cylinder bores and having a first end and a second end, said first end being connected to the corresponding cylinder bore, and said second end being selectively connected to and disconnected from the introducing passage in accordance with the rotation of the rotary valve; a means for transmitting a reaction force acting on the piston to the rotary valve, wherein said reaction force is generated in the compression chamber when the piston is in the discharge stroke, whereby the rotary valve is urged against the second end of the suction passage connected to the cylinder bore that is in the discharge stroke.