Variable displacement wobble plate type compressor with a wobble angle

Abstract

A variable displacement wobble plate type compressor with a variable angle non-rotary wobble plate, having a suction chamber for refrigerant returning from a refrigerating circuit via an evaporator, a discharge chamber for refrigerant after compression, suction and compression cylinder bores formed in a cylinder block, pistons reciprocating in the cylinder bores, a crankcase attached to the end of the cylinder block and receiving therein a drive and a wobble plate mechanism mounted about a drive shaft connectable to a rotary drive source, connected to the pistons to cause reciprocating motion of the pistons and capable of changing the wobble angle thereof and thereby change the strokes of the pistons, a first passageway for communicating the crankcase interior chamber with a discharge chamber to supply pressure acting as a back-pressure applied to the pistons, a control valve unit for closing and opening the first passageway, a second passageway extending through the drive shaft for communicating the crankcase interior chamber with the suction chamber to enable an extraction of the refrigerant from the crankcase interior chamber into the suction chamber, via a plurality of vent holes formed in and axially separately arranged in the circumference of the drive shaft, an annular sleeve element operatively connected to the drive plate and slidable on the drive shaft to cover a variable number of the plurality of the vent holes thereby changing the amount of extraction of the refrigerant in response to a change in the cooling load.