Patent ID: 8117960

Claim:
A water-cooled piston compressor comprising: at least one piston configured to axially compress air that is movably accommodated in a cylinder casing that is closed at an end side by a cylinder head, the cylinder head including a valve plate engaging an end face of the cylinder casing, the cylinder casing being double-walled, the end face including a plurality of cooling openings via which coolant flowing through the double-walled cylinder casing comes into contact with the valve plate, the valve plate having single inlet corresponding to one of the cooling openings of the cylinder casing for transferring the cooling water into the region of the cylinder head, at least one coolant port configured as an inlet for the coolant and being arranged on the outside of the cylinder casing, and a further coolant port configured as an outlet for the coolant and being arranged on one of the cylinder head and the cylinder casing such that the coolant, starting from the coolant port that forms the inlet, flows around the cylinder casing on both sides to effect a uniform cooling action, wherein the cylinder casing includes more than four cooling openings that are substantially in the shape of segments of a ring.