Sliding vane compressor

A sliding vane compressor, particularly for use in freon refrigeration system, comprising a rotatable hollow shaft having an interior;

• a cylindrical compressor rotor surrounding said shaft and having a set of first end faces;
• end covers enclosing said compressor rotor and having a set of second end faces abutting said first end faces, said end faces of said first and said second set each having a center and an outer periphery, said rotor being associated with a low pressure region of the compressor, said interior of said shaft being associated with a high pressure region of the compressor;
• and at least two vanes disposed in said rotor and adapted to compress a working medium, said vanes having valve means to control a medium flowing from the low pressure region, the end faces of at least one of said sets being formed with a plurality of grooves, said grooves being curved in the direction of rotation of said shaft and extending substantially radially from the outer periphery of the respective end face toward but short of the respective center to thereby prevent leakage of the working medium between the low pressure region and the high pressure region.