Capacity modultion system for a compression system for a heat pump/refridgerator

摘要

Disclosed is a capacity modulation apparatus for compressor to provide more effective adjustment of the compressor output to the load. The apparatus comprises a compression mechanism; a valve plate associated with the compression mechanism and including at least one port in fluid communication with the compression mechanism. A manifold is disposed adjacent to the valve plate. A cylinder is formed in the manifold; a piston disposed within the manifold and movable relative to the manifold between a first position separated from the valve plate and a second position engaging the valve plate. A valve element is disposed within the piston and movable relative to the piston and the manifold, the valve element movable between an open position spaced apart from the valve plate and permitting flow through the port and into the compression mechanism and a closed position engaging the valve plate and restricting flow through the port and into the compression mechanism. The piston includes an inner volume having a pressurized fluid or discharge pressure gas received from the compressor disposed therein, which imparts a force on the valve element to move the valve element against one end of the piston.