Refrigeration lubricants with at least one thiophosphorus additive for use in hydrofluorocarbon refrigeration systems. The thiophosphorus additives may improve the stability and metals and/or refrigerant compatibility of the refrigeration lubricant.

The present disclosure relates to a reciprocating-piston compressor (10), including a control device (12), which control device is designed to control a flow rate of the reciprocating-piston compressor (10), in particular in a continuously variable manner, and which control device has an input (18) for feeding input information, in particular suction pressure or high pressure of a corresponding compressor (10), and has at least one output (20) for controlling a control element (16), wherein the control device (12) is designed to generate a digital output signal, wherein the control element has a digitally controllable control valve (16), wherein the reciprocating-piston compressor (10) has at least one suction-gas volume (22) and at least one high-pressure volume (24), wherein a connection (26) is formed between the at least one suction-gas volume (22) and the at least one high-pressure volume (24) of the reciprocating-piston compressor (10), wherein the digitally controllable control valve (16) is arranged in the connection (26), wherein the reciprocating-piston compressor (10) has a shut-off device, in particular a valve, further in particular a check valve (28), which is arranged downstream of the high-pressure volume (24), as regarded in a flow direction of the refrigerant during normal operation of the reciprocating-piston compressor (10), wherein the at least one suction-gas volume and the at least one high-pressure volume and the control valve (16) are integrated into the reciprocating-piston compressor (10). The disclosure further relates to a refrigerating or air-conditioning installation or heat pump having a corresponding compressor (10), and to a corresponding control method.

A method for operating a linear compressor includes measuring a current induced in a motor of the linear compressor and calculating an observed current of the motor of the linear compressor using at least an electrical dynamic model for the linear compressor and a robust integral of the sign of the error feedback. The method also includes detecting a head crash within the linear compressor if an error between the observed current of the motor of the linear compressor and the measured current induced in the motor of the linear compressor is greater than a crash threshold.

In an interior permanent magnet motor, a magnet insertion hole of a rotor core is curved into an arc shape, and a convex portion side of the arc shape is arranged on a center side of a rotor. The magnet insertion hole has a first line, a second line, and a pair of third lines. The first line is located on the radially outer side of the second line. Each of the third lines connects the first line and the second line to each other. The first line includes an arc portion and a pair of concave portions. Each of the concave portions is located at an end of the arc portion of the first line.

A linear compressor comprising a cylinder part including a cylinder bore. A piston disposed in, and is slidable within, the bore. A main spring connects the cylinder part directly or indirectly to the piston. A connecting rod connects between the main spring and the piston. A stator has an air gap, and the connecting rod passes through the air gap. At least one armature pole is located along the connecting rod.

A compressor according to an embodiment includes: a cylinder; a piston configured to be reciprocable in the cylinder; a suction space capable of communicating with a working chamber formed by the cylinder and the piston; a discharge space capable of communicating with the working chamber; a partition wall portion disposed so as to surround the working chamber, and separating the suction space and the discharge space; and a cooling medium path formed in the partition wall portion.

The present invention describes a valve mechanism for refrigerating machines compressors. More specifically, the valve mechanism operates to allow the equalization of pressure between the compression chamber of a reciprocating compressor and the discharge volume of the same compressor. This equalization is aimed at reducing the torque required for departure. The present invention lies in the field of mechanical engineering, more specifically in the field of fluid and cooling mechanics.

In a sealed compressor, electrically-operated element and compressive element driven by electrically-operated element are housed in the inside of sealed container. Compressive element includes shaft formed of main shaft and eccentric shaft, and cylinder block having: bearing which pivotally supports main shaft of shaft; and cylinder. Further, the sealed compressor includes piston which is movable in the cylinder in a reciprocating manner, and connecting portion which connects eccentric shaft and piston to each other. Electrically-operated element is an outer-rotor-type motor which includes stator, and rotor which surrounds an outer periphery of stator and is disposed coaxially with stator. Further, stator is fixed to outer peripheral surface of bearing by adhesive agent.

A reciprocating compressor with a head-holding turret in the upper portion of which one or more recesses, open to the outside, are defined, which reduce as much as possible the contact surface with the valve carrier plate above.

In order to operate as energy-efficiently as possible a refrigerant compressor, comprising a reciprocating piston compressor and an electric motor, an overall housing having a motor housing portion for the electric motor and a compressor housing portion for the reciprocating piston compressor, a suction connector connected to a low-pressure side of the reciprocating piston compressor, a pressure connector connected to a high-pressure side of the reciprocating piston compressor, wherein provided in the compressor housing portion is at least one cylinder of the reciprocating piston compressor, which has a piston that is movable in a cylinder bore formed in the compressor housing portion, a valve plate closing the cylinder bore, and a cylinder head that spans the valve plate and forms part of the compressor housing portion, it is proposed that a mechanical performance control unit should be provided by which the low-pressure side and the high-pressure side are connectable to one another for the purpose of reducing performance, and that there should be provided in the region of the cylinder head a nonreturn valve that is held against the cylinder head and that allows a refrigerant stream exiting therefrom on the high-pressure side and blocks a refrigerant stream counter to this refrigerant stream.