Slant plate type compressor with variable displacement mechanism

Abstract

A slant plate type compressor, such as a wobble plate type compressor, with a variable displacement mechanism for use in a refrigeration circuit is disclosed. Two passageways communicate between the crank chamber and the suction chamber in the cylinder block. A bellows is disposed in a first passageway and controls communication between the crank chamber and the suction chamber in the first passageway. The bellows operates in accordance with the crank chamber pressure. A control valve is disposed in the second passageway and controls communication between the crank chamber and the suction chamber in the second passageway in response to signal from an external sensor. This configuration enables the compressor to be operated at maximum capacity when the refrigeration circuit is turned on until the temperature in the passenger compartment of a car reaches a desired temperature without input from the pressure in the crank chamber. After the temperature in the passenger compartment of the car reaches the desired temperature, the compressor operation is controlled by the bellows based on the crank chamber pressure. Therefore, the cooling characteristics of the compressor are improved and the temperature in the passenger compartment of the car can be controlled better.