Patent ID: 9695691
Date: 2017-07-04
CPC Classifications: F01C,F04C

Claim:
1. A gas compressor, comprising: a compressor body; and a housing which covers the compressor body, the compressor body, including: a rotor which has an approximately cylindrical shape, and rotates around a shaft; a cylinder which has an inner circumferential surface having an outline shape surrounding the rotor from an outside of an outer circumferential surface of the rotor, and in which a first discharge part and a second discharge part are formed; a plurality of plate-like vanes which receive a back pressure from vane grooves formed in the rotor and freely protrude outward from the rotor; and two side blocks, a first of the two side blocks being provided on a first end surface side of the rotor and the cylinder and a second of the two side blocks being provided on a second end surface side of the rotor and the cylinder, wherein the compressor body is formed such that a plurality of compression chambers divided by the rotor, the cylinder, the side blocks and the vanes are formed inside, and each of the plurality of compression chambers performs only one cycle of intake, compression and discharge of gas through the first discharge part in a period of one rotation of the rotor, and an outline shape of a cross section of the inner circumferential surface of the cylinder is formed such that in the period of the one rotation of the rotor, regions (1) to (4) are consecutively provided in order of the regions (1) to (4) as follows: (1) a region in which a capacity of one of the compression chambers increases, (2) a region in which the capacity of the one compression chamber reduces, (3) a region in which a capacity reduction rate of the one compression chamber becomes smaller than a capacity reduction rate of the region (2), and (4) a region in which the capacity reduction rate of the one compression chamber becomes larger than a capacity reduction rate of the region (3); wherein the second discharge part is configured to discharge gas in the one compression chamber in a state in which a pressure of the gas in the one compression chamber reaches a discharge pressure at a stage before the one compression chamber faces the first discharge part by rotation of the rotor; and wherein a communication passage connects the second discharge part to the first discharge part such that the gas discharged through the second discharge part must flow through the communication passage to join with gas discharged through the first discharge part and then flow to a discharge passage to an outside of the compressor body.