Swash plate type compressor with a central discharge passage

A swash plate type compressor comprising:

• a cylinder block having opposite ends, a central axial bore, a plurality of working bores extending parallel to each other around the central axial bore, a suction inlet, and a swash plate chamber intersecting the central axial bore and the working bores;
• valve plates attached to the ends of the cylinder block, respectively, the valve plates having valve ports and associated valve elements to cover and uncover the valve ports;
• first and second housings attached to the ends of the cylinder block over the valve plates, respectively;
• each of the first and second housings having at least a discharge chamber formed between each of the first and second housings and each of the valve plates;
• a drive shaft inserted in the central axial bore of the cylinder block and rotatably supported therein;
• a swash plate accommodated in the swash plate chamber and fixed to the drive shaft for rotation therewith;
• a plurality of double headed pistons inserted in the respective working bores for forming compression chambers in each of the working bores on either side of each of the double headed pistons and engaged with the swash plate via shoes so that the pistons reciprocally move in the respective working bores upon a rotation of the swash plate;
• at least one suction passage for introducing a medium from the suction inlet to the compression chambers via the swash plate chamber;
• and
• a discharge passage for connecting the discharge chamber in one of the first and second housings to the other housing;
• wherein the discharge passage is arranged at least partly in the drive shaft.