Piston type compressor with a rotary suction valve

A piston type compressor provided with a body, a drive shaft rotatably supported in the body, at least one gas receiving chamber formed in the body for receiving refrigerant gas mixed with lubricant oil before compression, at least one gas discharge chamber formed in the body for receiving compressed refrigerant gas, a plurality of axial cylinder bores formed in the body and arranged around an axis of rotation of the drive shaft, and a plurality of pistons slidably received in the plurality of cylinder bores and reciprocable in response to the rotation of the drive shaft, the pistons defining compression chambers in the cylinder bores, comprising:

• a rotary valve means arranged to be rotatable with said drive shaft and having an outer peripheral wall and opposing end portions;
• a recessed chamber disposed in the compressor body for receiving said rotary valve means, said recessed chamber being surrounded by an inner wall extending around the axis of rotation of said drive shaft, said outer peripheral wall of the rotary valve means being slidably disposed against the inner wall of said recessed chamber;
• a suction passageway formed in the rotary valve means for permitting suction of the refrigerant gas before compression from the gas receiving chamber into the respective compression chambers in timed relationship with the reciprocation of said pistons during rotation of said rotary valve means, the suction passageway having an inlet communicating with the gas receiving chamber and an outlet located on the outer peripheral wall of said rotary valve means for communication with the compression chambers;
• and
• a groove disposed in the outer peripheral wall of the rotary valve means, said groove being connected with said outlet of the suction passageway and extending in the direction of rotation toward one of said opposing ends of the rotary valve means along said outer circumferential wall, said groove supplying said lubricant oil within the refrigerant gas in the suction passageway to and between the outer peripheral wall of the rotary valve means and the inner wall of the recessed chamber during rotation of the rotary valve means.