A driving unit and a linear compressor including the same are provided. The driving unit includes an inner stator, a bobbin surrounding the inner stator in a circumferential direction, a coil wound on the bobbin, a plurality of stator cores surrounding the bobbin and spaced apart from each other in the circumferential direction, and a plurality of permanent magnets disposed between the inner stator and the plurality of stator cores. A cross section of the bobbin may include a pair of straight portions facing each other and a curved portion connecting the pair of straight portions.

An electric motor and a compressor having an electric motor. The electric motor may include a stator, and a rotor provided with a rotational shaft, a rotor core coupled to the rotational shaft, and permanent magnets coupled to the rotor core. The rotor core may include a first core to which the permanent magnets may be coupled, and a second core made of a magnetic material and coupled to an end of the first core in an axial direction. The second core may have outer surfaces disposed inside of extension lines extending in the axial direction from inner surfaces of the permanent magnets.

Variable volume ratio compressors may be controlled using a switching parameter based on compressor speed and suction density to improve the matching of compressor volume ratio to desired discharge conditions. Delay periods may be implemented in the determination of when to change volume ratio to control the frequency of changes to the volume ratio. The switching parameter may be a product of the compressor speed and suction density. The volume ratio of the compressor may be controlled by switching valves directing pressure to a piston of a variable volume ratio system of the compressor.

In order to increase the efficiency, in respect of the quantity of refrigerant to be compressed, of a reciprocating piston compressor for refrigerant, comprising a compressor housing having at least one compressor stage that has at least one cylinder unit, wherein a piston is movably arranged in the cylinder unit, a cylinder drive that is arranged in the compressor housing, for the at least one piston, a valve plate that closes off a cylinder chamber and is provided with at least one suction valve which, for its part, has a suction opening, arranged in the valve plate and closable by a suction vane, and has at least one outlet valve with an outlet opening, wherein the at least one suction valve and the at least one outlet valve are associated with the respective cylinder chamber, and a cylinder head that is arranged on an opposite side of the valve plate to the cylinder chamber, it is proposed that the valve plate should have, on its side facing the cylinder chamber, a recess, which is arranged inside an external contour of an abutment face of the suction vane that is associated with the suction opening and which extends from the suction opening and is open toward this abutment face.

In order to improve a refrigerant compressor of the type mentioned in the introduction such that it is ensured that, even in the event of a tilt along a longitudinal direction of the refrigerant compressor unit relative to a horizontal course of the longitudinal direction, lubricant can reliably be drawn off by suction out of the lubricant sump, in order to prevent excessive accumulation of lubricant in the lubricant sump, it is proposed that there should be provided on the bottom side of the motor compartment a receiving point that takes a form such that the receiving point supplies lubricant from the lubricant sump to the suction-removal unit.

A rotary compressor system includes a compressor housing that includes a compressor motor that draws in fluid from a suction side. The fluid is compressed within a compression chamber and discharged through a discharge side. The compression chamber is disposed between the suction side and the discharge side. An overload-protection switch is electrically coupled in series with the compressor motor and is adapted to cut power to the compressor motor responsive to an overload event. A solenoid valve is fluidly coupled between the compression chamber and a location upstream of the suction side and is electrically coupled in series with the overload-protection switch. An interruption of electrical current to the compressor motor also interrupts electrical current to the solenoid valve, which opens the solenoid valve to equalize pressure between the suction side and the discharge side.

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.

Embodiments of the present invention reduce the amount of energy required to operate air-conditioners and refrigerators by providing a vapor-compression system that harnesses a low- or no-cost source of energy, namely, heat, and uses the harnessed heat to power a new kind of compressor, called a “burst compressor” and a new kind of pump, called a “vapor pump.” The heat-driven burst compressor pressurizes the refrigerant, while also providing “push and pull” vapor refrigerant to the vapor pump. The vapor pump, actuated by the high pressure refrigerant in gaseous form provided by the burst compressor, is configured to pump a combination of gaseous, vaporous and liquid refrigerant out of the receiver tank and inject that low pressure refrigerant mix into the burst compressor, where it is heated to change the state of the refrigerant to a heated, pressurized gas. Then the heated, pressurized gas is released in bursts into the other components of the vapor compression cycle. Thus, embodiments of the present invention use heat to provide cold. Because of this arrangement, vapor-compression systems constructed and arranged to operate according to embodiments of the present invention are able to provide air-conditioning and/or refrigeration much more efficiently and with much less expense than traditional vapor compression systems for air-conditioning and refrigeration.

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 method for operating a variable capacity drive circuit of a compressor includes operating first and second four-quadrant switches in a first state in which the first four-quadrant switch is closed and the second four-quadrant switch is open such that a voltage seen by the motor is equal to an AC line voltage. The method also includes operating the first and second four-quadrant switches in a second state where the first four-quadrant switch is open and the second four-quadrant switch is closed such that the voltage seen by the motor is to zero. Further, the method includes providing a positive firing angle and a negative firing angle for defining when the first and second four-quadrant switches are operated in each of the first and second states. Moreover, the method also includes transitioning between the first and second states using the firing angles at a switching frequency determined by the AC line voltage frequency.