Patent ID: 8192187

Claim:
A compressor comprising: a disc-shaped screw rotor arranged to rotate about a center axis, the screw rotor having a plurality of spirally extending groove portions disposed radially outwardly from the center axis of the screw rotor, with the groove portions being formed in at least one end face of the screw rotor facing a direction parallel to the center axis of the screw rotor; and a gate rotor arranged to rotate about a center axis and which has a plurality of tooth portions circumferentially arranged on an outer circumference of the gate rotor, with the groove portions of the screw rotor and the tooth portions of the gate rotor being engaged with each other to form a compression chamber, the screw rotor and the gate rotor being configured and arranged such that a first plane contains the screw rotor center axis, a second plane orthogonally intersects the screw rotor center axis, and a third plane orthogonally intersects the first plane and the second plane, the gate rotor center axis is on the third plane, at least one of the tooth portions of the gate rotor does not overlap with the first plane as viewed in a direction orthogonal to the third plane, and the gate rotor center axis is inclined relative to the second plane so that the tooth portions of the gate rotor closer to the screw rotor than other tooth portions are closer to the screw rotor center axis than the other tooth portions of the gate rotor farther from the screw rotor as viewed in the direction orthogonal to the third plane.