The reciprocating compressor has a cylinder with a compression chamber where a piston can slide between a crank-side position and a head-side position; a piston rod is mechanically connected to the piston and during operation of the compressor, slides in a hole of the compression chamber; there is a small gap between the hole and the piston rod; in order to avoid leakage from this gap a jacket is arranged around the piston rod and is sealed on one side to the piston and on the other side to the cylinder at the gap.

A gas bearing is disclosed. The gas bearing may include a cylinder with an inner cylinder radius. The gas bearing may include a piston with a piston radius, wherein the inner cylinder radius is larger than the piston radius, wherein the piston is located within the cylinder. The gas bearing may include a gas bearing radius, wherein the gas bearing radius is greater than the piston radius and less than the inner cylinder radius. The gas bearing may include a gap that exists between the cylinder and the piston, wherein the gap contains a pressurized gas, the pressurized gas configured to prevent contact between the cylinder and the piston. The gas bearing may include a gas bearing interface, wherein the gas bearing interface is positioned to control a size of the gap.

A linear compressor is provided. The linear compressor may include a cylinder that defines a compression space for a refrigerant; a piston that axially reciprocates inside the cylinder; a motor configured to provide a drive force to the piston; a discharge valve configured to discharge the refrigerant compressed in the compression space; and a discharge cover having a discharge space in which the refrigerant discharged through the discharge valve flows. The discharge valve and the discharge cover may be arranged inside the motor.

A compressor crankcase assembly is provided for an air compressor. In one example, a compressor crankcase assembly includes a crankcase made of a material comprising at least 50% by weight aluminum and a crankcase liner disposed within the crankcase. The crankcase has a protrusion that is at least partially disposed within the groove of the crankcase liner.

An axial piston machine may include a a housing having vapor, cylinder chamber and wobble-plate chambers. The machine may have cylinders arranged annularly around a shaft in the cylinder chamber and having pistons arranged therein in a translationally movable manner, a valve disk connected to the shaft in a rotationally fixed manner and arranged in the vapor chamber, and a wobble plate connected to one of the pistons via a cup and ball bearing and to the shaft in a rotationally fixed manner, the wobble plate being arranged in the wobble-plate chamber. The housing may have steam-chamber, cylinder, and wobble-plate housing parts connected to one another. A cylinder sleeve having a radially protruding collar may be provided in at least one cylinder, wherein the cylinder sleeve may be retained via the collar in a cut-out in the cylinder housing part, which may adjoin a parting plane between the vapor-chamber and cylinder housing parts. The vapor chamber may be closed off by a first cover, which may be connected to the vapor-chamber housing part and which may be designed as a shaped sheet-metal part.

A compressor unit of a cryogenic refrigeration device includes a compression chamber that is connectable via a transfer line to an expander unit. A piston is configured to alternately compress and decompress a gaseous working agent in the compression chamber. An electromagnetic actuator includes a stator assembly with a driving coil that is wound about the longitudinal axis and that is enclosed within a toroidal back iron except for a coaxial cylindrical gap in a radially outward facing surface. A movable assembly connected to the piston includes two movable permanent magnets separated by a ferromagnetic spacer radially exterior to the stator assembly. The movable magnets are magnetized parallel to the longitudinal axis and opposite to one another such that an alternating electrical current in the driving coil causes the movable assembly to parallel to the longitudinal axis to periodically drive the piston into and out of the compression chamber.

A compression unit, for a volumetric compressor, includes at least one cylinder, at least one piston, a drive shaft, operable in rotation around a rotation axis and associated with the at least one piston through a connecting rod/crankshaft kinematic mechanism, a casing for supporting the at least one cylinder and for housing at least one portion of the drive shaft and of the connecting rod/crankshaft kinematic mechanism, and which includes at least one air intake in communication with the outside of the compression unit and defining at least one passage for the air to be drawn therein and to be supplied to the at least one cylinder; the air intake is in fluid communication with the interior of the at least one cylinder through a path which is extended inside the casing and through at least one section of a wall of the at least one cylinder.

A linear compressor is provided. The linear compressor may include a shell including a suction inlet, a cylinder provided in the shell to define a compression space for a refrigerant, a piston reciprocated in an axial direction within the cylinder, a discharge valve provided on or at one side of the cylinder to selectively discharge the refrigerant compressed in the compression space, at least one nozzle disposed in the cylinder to introduce at least a portion of the refrigerant discharged through the discharge valve into the cylinder, and a passage to guide the refrigerant discharged from the discharge valve to the at least one nozzle.

A linear compressor and a refrigerator including a linear compressor are provided. The linear compressor may include a shell coupled to a suction inlet, through which a refrigerant may be introduced, and a discharge outlet, through which the refrigerant may be discharged, a cylinder disposed within the shell to accommodate a piston reciprocated to compress the refrigerant introduced through the suction inlet, a frame that accommodates the cylinder, the frame being mounted inside the shell, and a discharge cover coupled to a front surface of the frame to discharge the refrigerant compressed by the piston to the discharge outlet. A front surface of the cylinder that faces the discharge cover may be spaced a predetermined distance from the discharged cover.

An air valve connecting device or attachment includes a casing extended from a housing, a mouth engaged in the casing and having a compartment for engaging with either a US or French inflation valve, a follower slidably engaged in the casing and the housing and engageable with the mouth for compressing the mouth to grasp either of the inflation valves, a tube slidably engaged in the follower and extendible into the mouth, an actuator engaged in the housing and having a space for engaging with the follower, and the actuator includes a cam member for engaging with the follower and for forcing the follower to compress the mouth and to grasp either of inflation valves to the casing.