A linear compressor includes: a frame comprising a body portion, a flange portion extending from a front side of the body portion along a radial direction of the body portion, and a bearing communication hole that is in fluid communication with a front surface of the flange portion and an inner circumferential surface of the body portion, a cylinder coupled to the body portion, a piston that is disposed in the cylinder and that is configured to reciprocate along an axial direction of the cylinder, and a valve member that is disposed at the frame and that is configured to open and close the bearing communication hole based on a pressure of air between the cylinder and the piston.

A linear compressor includes a mover which linearly reciprocates, a stator generating a driving force to allow the mover to linearly reciprocate and having a cylinder space formed on an inner circumferential surface thereof, a cylinder inserted into the cylinder space of the stator and having a compression space compressing a refrigerant, a piston reciprocating in an axial direction inside the cylinder, a frame provided on one side of the stator in an axial direction and supporting the stator in the axial direction, and a cylinder support member separated from the frame, provided between an inner circumferential surface of the stator and an outer circumferential surface of the cylinder, having one end fixed to the stator and the other end fixed to the cylinder, and supporting the cylinder with respect to the stator in the axial direction.

A linear compressor includes a cylinder that defines a compression space of a refrigerant and has a cylindrical shape, and a piston disposed in the cylinder and reciprocating along an axis of the cylinder. The cylinder includes a supply port radially passing through the cylinder, and a recess formed on an inner circumferential surface of the cylinder and communicating with the supply port. The supply port includes a first supply port and a second supply port disposed in a rear of the first supply port, and the recess includes a first recess and a second recess disposed in a rear of the first recess. The first recess and the second recess are formed in different shapes.

A compressor includes: a driving unit including a stator, a rotor, and a rotary shaft provided in the rotor, having an oil guide path formed at an inner side in a radius direction; a compression unit coupled to the rotary shaft, having a cylinder and a piston reciprocating in the cylinder by a driving force of the driving unit; and an oil supply unit coupled to a lower end of the rotary shaft, supplying oil toward the compression unit. The oil supply unit includes a rotary portion for supplying oil toward the oil guide path while being rotated together with the rotary shaft and a fixed portion having an inner space partitioned to accommodate at least a portion of the rotary portion, and the oil guide path is formed to pass through the rotary shaft along a length direction.

A refrigerating apparatus using a non-azeotropic mixed refrigerant may include a compressor operable in a continuous operation mode and configured to compress the non-azeotropic mixed refrigerant, a condenser configured to condense the refrigerant compressed by the compressor, an expander configured to expand the refrigerant condensed by the condenser, and an evaporator configured to evaporate the refrigerant expanded by the expander. A pressure difference (ΔP) of the non-azeotropic mixed refrigerant has a value included in a range of 340 kPa<ΔP<624.7 kPa. Therefore, reliability of components, such as a piston, in the refrigerating apparatus using the non-azeotropic mixed refrigerant may be further improved.

A linear compressor includes a housing defining a sump for collecting a lubricant and a pump for circulating a flow of lubricant within the housing. A heat dissipation or heat exchange assembly includes a plate mounted on a lower portion of the housing to define one or more fluid passageways between the plate and the housing. Hot oil is collected from the working components of the linear compressor and is passed through the one or more fluid passageways to discharge heat through the housing before the oil is returned to the sump.

A system for starting an air compressor in a low-temperature state includes a motor configured to generate rotation force according to a control signal of a controller, a piston configured to compress air through reciprocating motion using rotation force of the motor, an oil pump configured to provide oil stored in an oil pan to a rotation axis of the motor, an oil supply line configured to connect the oil pan to the oil pump, a recovery line configured to connect a discharge port of the oil pump to the oil supply line, and a valve connected to the recovery line and controlled by the controller, where the controller controls an on/off state of the valve based on a temperature of the motor, revolutions per minute (RPM) of the motor, or a pressure of the oil pump.

A linear compressor includes a mover which linearly reciprocates, a stator generating a driving force to allow the mover to linearly reciprocate and having a cylinder space formed on an inner circumferential surface thereof, a cylinder inserted into the cylinder space of the stator and having a compression space compressing a refrigerant, a piston reciprocating in an axial direction inside the cylinder, a frame provided on one side of the stator in an axial direction and supporting the stator in the axial direction, and a cylinder support member separated from the frame, provided between an inner circumferential surface of the stator and an outer circumferential surface of the cylinder, having one end fixed to the stator and the other end fixed to the cylinder, and supporting the cylinder with respect to the stator in the axial direction.

Apparatus for compressing cryogenic fluid in at least one compression stage comprising at least one piston and at least one sleeve delimiting at least one compression chamber, a shaft that is able to move in translation along a longitudinal axis (A), the shaft being connected to the piston(s) or sleeve(s) and being able to move with an alternating movement in two opposite directions to ensure phases of compression and intake of fluid into the at least one compression chamber by moving the at least one piston and the at least one sleeve in a relative manner, characterized in that the shaft comprises a portion of reduced cross section in the longitudinal direction (A), said portion of reduced cross section separating two adjacent parts of the shaft, the shaft also comprising at least one linking element made of material that is less thermally conductive than the constituent material of the shaft, in particular a composite material, said at least one linking element having two ends connected respectively to the two adjacent parts of the shaft.

A linear compressor includes a housing defining a sump for collecting a lubricant and a pump for circulating a flow of lubricant within the housing. A heat dissipation or heat exchange assembly includes a plate mounted on a lower portion of the housing to define one or more fluid passageways between the plate and the housing. Hot oil is collected from the working components of the linear compressor and is passed through the one or more fluid passageways to discharge heat through the housing before the oil is returned to the sump.