US Patent 7153112 Compressor and a method for compressing fluid

A compressor and a method for compressing fluid according to which a liner is disposed on the inner wall of a housing defining a bore. At least one slot and at least one discharge port are provided in the liner. A rotor is rotated in the housing with its outer surface in a closely spaced relation to the inner wall of the liner, and an additional rotor extends through the slot in the liner and intermeshes with the first rotor to compress fluid introduced between the rotors before it is discharged through the port.