Abstract: A rotary vane gas compressor has a cylinder, a rotor in the cylinder, and vanes slidably disposed in radial vane grooves in the rotor to define compression chambers for intaking, compressing and discharging compressed gas during rotation of the rotor. A flat groove communicates with bottom portions of the vane grooves during intaking and compression of the gas in the compression chambers, and a high pressure supplying hole communicates with the bottom portions of the vane grooves during end stage compression of the gas at times when the bottom portions of the vane grooves are not in communication with the flat groove. A communication passage establishes communication between the flat groove and the high pressure supplying hole at the start of operation of the gas compressor to supply high pressure gas to the vane groove bottom portions during start-up to quickly urge the vanes into contact with the cylinder.

Abstract: To provide a gas compressor improved in terms of the vane projectability at the start of the compressor. To achieve the above object, there is provided a communication passage establishing communication between a high pressure supplying hole and a flat groove at the start of the compressor, and high pressure refrigerant gas discharged into the high pressure supplying hole at the start of the compressor is supplied to the flat groove, whereby high pressure refrigerant gas is supplied to vane groove bottom portions, making it possible to improve the projectability of vanes.

Abstract: To provide a gas compressor that is suitable for reducing cost for the overall compressor without degrading the oil separation performance needed for the compressor and that may keep the oil separation performance constant for a long period of time. An oil separator having a pipe structure composed only of a discharge pipe formed integrally with a side block as a means for separating a lubricant oil component contained in high pressure cooling medium gas is adapted. In this case, the discharge pipe is adapted to form a discharge route for the high pressure cooling medium gas without any bypass immediately before an inner wall of a compressor case from a first discharge chamber. The separation of the lubricant oil component is performed by collision of the high pressure cooling medium gas, immediately after discharged from a cylinder discharge port to the first discharge chamber, against the inner wall of the compressor case through the discharge pipe without reducing a high flow rate.

Abstract: To provide a gas compressor that is suitable for reducing cost for the overall compressor without degrading the oil separation performance needed for the compressor and that may keep the oil separation performance constant for a long period of time. An oil separator having a pipe structure composed only of a discharge pipe formed integrally with a side block as a means for separating a lubricant oil component contained in high pressure cooling medium gas is adapted. In this case, the discharge pipe is adapted to form a discharge route for the high pressure cooling medium gas without any bypass immediately before an inner wall of a compressor case from a first discharge chamber. The separation of the lubricant oil component is performed by collision of the high pressure cooling medium gas, immediately after discharged from a cylinder discharge port to the first discharge chamber, against the inner wall of the compressor case through the discharge pipe without reducing a high flow rate.