An improved air compressor is provided. The air compressor includes a cylinder block having a head deck that defines a piston bore for reciprocal movement of a piston therein. The head deck further includes first and second ramped surfaces that slope downward toward the peripheral edge of the piston bore. A valve plate is in direct contact with the upper surface of the head deck, the valve plate having a leaf valve. During an intake stroke of the piston, the leaf valve deflects downward into direct engagement with the first and second ramped surfaces. Because the air compressor lacks a lower gasket between the valve plate and the head deck, the cost and assembly time associated with the lower gasket are eliminated.

A swash plate compressor including a cylinder block accommodating a piston for compressing a refrigerant, a front housing coupled to the front of the cylinder block and having a crank chamber, a rear housing having a suction chamber and a discharge chamber and coupled to the rear of the cylinder block. The swash plate compressor includes a valve assembly with a valve plate inserted into the rear housing, a gasket in the cylinder block, a suction plate between the valve plate and the cylinder block, a variable orifice module having a first orifice hole for refrigerant passing, a second orifice hole communicating with the suction chamber to discharge the refrigerant passing through the first orifice hole to the suction chamber, and an intermediate passage connecting the orifice holes, the first orifice hole having a variable reed, a degree of opening of which is varied depending on the refrigerant pressure.

A direct drive air pump has a motor and a pumping mechanism connected to an end of the motor, and further has an auxiliary pumping mechanism connected to the other end of the motor, and a tube connected with the pumping mechanism and the auxiliary pumping mechanism. In each one of the pumping mechanism and the auxiliary pumping mechanism, a cylindrical body has a top plate having an exhaust hole. A single O-ring is used to seal between the cylindrical body and a cylindrical cover for reducing the sealing portions. A valve block of a non-return valve can co-work with a spring for opening and closing the exhaust hole. The valve block is soft for closing the exhaust hole well and reducing the noise of collision between the valve block and the top plate.

A valve plate assembly for a compressor according to the principles of the present disclosure includes a valve plate and a suction valve retainer. The valve plate is configured to separate suction-pressure working fluid entering a cylinder of the compressor from discharge-pressure working fluid exiting the cylinder of the compressor, the valve plate defining a discharge valve seat. The suction valve retainer is configured to retain a suction valve within a suction valve seat disposed about a central longitudinal axis of the cylinder and to extend radially outward from the central longitudinal axis of the cylinder without extending beyond a suction passage of the compressor.

A valve plate assembly for a compressor according to the principles of the present disclosure includes a valve plate and a suction valve retainer. The valve plate is configured to separate suction-pressure working fluid entering a cylinder of the compressor from discharge-pressure working fluid exiting the cylinder of the compressor. The valve plate defines a discharge valve seat. The suction valve retainer is configured to retain a suction valve within a suction valve seat disposed about a central longitudinal axis of the cylinder.

A piston for a compressor and a compressor including the same are disclosed. The piston is used in a compressor which compresses and discharges refrigerant suctioned into a cylinder. The piston includes a cylindrical slider and a head. The slider has an outer diameter corresponding to an inner diameter of the cylinder and defines a suction space in which the refrigerant suctioned in the cylinder is received. The head is coupled to the slider, in which a compression space is provided in the front and a suction space is provided in the rear, and in which a suction port communicating with the suction space and the compression space is formed, in which the head includes an inner body and an outer body surrounding the inner body, and the suction port is formed between the inner body and the outer body.

A compressor may include a housing, a piston, a valve plate, a discharge valve and a head cover. The housing defines a cylinder. The piston is disposed within the housing and is movable within the cylinder. The valve plate is mounted to the housing and may include a discharge passage extending through the valve plate and defined by a discharge valve seat. The discharge valve is movable between a first position in which the discharge valve is seated on the discharge valve seat to restrict fluid flow through the discharge passage and a second position in which the discharge valve is spaced apart from the discharge valve seat to allow fluid flow through the discharge passage. The head cover may include a guide post including a pocket that receives a valve stem of the discharge valve.

A piezoelectric pump includes a first faceplate, a second faceplate, a diaphragm, a first peripheral wall, and a second peripheral wall. The diaphragm includes a vibrating portion to which a piezoelectric device is attached, a frame portion, and a connecting portion. The connecting portion defines a third opening that allows a first pump chamber and a second pump chamber to communicate with each other. The first pump chamber is provided with an annular first valve surrounding a first opening at a distance from the first opening in plan view from a major surface of the first faceplate toward a major surface of the diaphragm.

A piezoelectric pump includes a first faceplate, a second faceplate, a diaphragm, a first peripheral wall, and a second peripheral wall. The diaphragm includes a vibrating portion to which a piezoelectric device is attached, a frame portion, and a connecting portion. The connecting portion defines a third opening that allows a first pump chamber and a second pump chamber to communicate with each other. The first pump chamber is provided with an annular first valve surrounding a first opening at a distance from the first opening in plan view from a major surface of the first faceplate toward a major surface of the diaphragm.

A swash plate compressor includes a cylinder block accommodating a piston for compressing a refrigerant, a front housing coupled to the cylinder block and having a crank chamber, a rear housing having a suction chamber and a discharge chamber and coupled to the cylinder block, and a suction reed plate inserted between a valve plate and the cylinder block. The swash plate compressor includes: a first orifice hole through which the refrigerant in the crank chamber passes; a second orifice hole communicating between the first orifice hole and the suction chamber; an intermediate flow path configured to connect the first orifice hole and the second orifice hole; and the valve plate inserted into the rear housing and having a suction chamber pressure-maintaining space connected to the suction chamber and configured to maintain a pressure equal to a pressure in the suction chamber.