The invention relates to a device and a method for compressing a working medium, comprising: compressing a drive medium in a compressor; moving a drive piston within a first cylinder by means of the compressed drive medium; moving a high-pressure piston, which compresses the working medium, within a second cylinder by means of the drive piston; and transferring heat from the compressed working medium to the compressed drive medium before the compressed drive medium enters the first cylinder of the drive piston.

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 compressor is disclosed. The compressor compressing and discharging a refrigerant sucked inside a cylinder includes a frame configured to support the cylinder, and a discharge cover assembly disposed in front of the frame. A gas layer is formed between the discharge cover assembly and the frame.

An assembly includes a housing including a first assembly portion and a cover including a second assembly portion. One of the first assembly portion and the second assembly portion includes: (i) a small diameter inner circumferential wall, a large diameter inner circumferential wall, and an inner stepped portion; or (ii) a large diameter outer circumferential wall, a small diameter outer circumferential wall, and an outer stepped portion. A method for manufacturing the assembly includes a press-fitting step of fitting the housing and the cover by press-fitting to form a circumferential gap that is open in an axial direction and a welding step of welding the housing and the cover at the circumferential gap.

A movable core-type reciprocating motor and a reciprocating compressor having a movable core-type reciprocating motor are provided. The motor may include a stator including an inner stator and an outer stator; a magnet coil wound between the inner stator and the outer stator; a magnet fixed to at least one of the inner stator or the outer stator so as to be at least partially positioned within a range of the air gap; and a mover including a movable core disposed in the air gap and made of a magnetic material to perform a reciprocation movement with respect to the stator.

A linear compressor includes a shell, a frame in the shell, a cylinder defining a compression space, a piston in the cylinder, a motor assembly configured to drive the piston, a discharge cover unit defining a discharge space, a discharge valve configured to selectively open and close the compression space, and a valve spring assembly configured to provide elastic force that causes the discharge valve to contact the cylinder. The discharge cover unit includes a cover housing that defines an opening configured to communicate with the discharge space, a discharge cover that inserts into the cover housing through the opening, that contacts an inner surface of the cover housing, and that covers the opening, and a fixing ring configured to be positioned at an inner surface of the discharge cover. A thermal expansion coefficient of the fixing ring is greater than that of the discharge cover.

A multi-cylinder reciprocating compressor, especially suitable for carbon dioxide frigorific circuits, wherein the high-pressure chambers of the heads are connected via an external manifold, comprising a high-pressure cock which, in co-operation with the casing, defines a channel which environmental air flows through to remove heat.

Systems, devices, and methods of manufacture are provided for a cylindrical compressor with a standardized shell and core. The compressor including a cylindrical cast metal shell having a shell bore extending longitudinally therethrough and configured to receive a cylindrical cast metal core. The core having a core bore extending longitudinally therethrough defining a core bore diameter within a predefined range of diameters and corresponding to a shell bore diameter. The core having an outer diameter configured to provide an interference fit between the core and the shell when the core is disposed within the shell. The compressor including a plurality of valve assemblies extending through the shell and the core so as to interface a valve of the valve assembly with the core bore and further including cylinder head coupled to the shell, a piston rod assembly configured within the core bore, and a packing case coupled to the core.

An air sampling pump includes a reciprocating piston for operating a diaphragm assembly. The diaphragm includes a valve head including a fluid inlet and a fluid outlet and a fluid chamber defining a fluid path between the inlet and outlet. A diaphragm sealing engages the valve head and encloses the fluid chamber. The diaphragm includes a piston diaphragm membrane portion coupled to the piston for reciprocating with the piston and reciprocation of the piston causes a change in air pressure within the fluid chamber to cause air to move from the fluid inlet toward the fluid outlet. The diaphragm includes a damper membrane portion, which cooperate to reduce an amplitude of pulsation in the airflow at the fluid inlet and fluid outlet.

A linear compressor includes a frame including a frame body, a frame head that extends from a front end of the frame body, a flange groove defined in the frame head, and a body hole that passes through the frame body; a cylinder including a cylinder body inserted into the body hole, a cylinder flange, and a cylinder head provided on a front end of the cylinder flange; and a lock ring press-fitted to be coupled to the flange groove and provided in a space defined between the cylinder head and an inner circumferential surface of the flange groove.