Abstract: An expansion valve includes a valve element, a valve seat as well as a biasing member. The valve element and the valve seat are arranged in a first fluid passage of the expansion valve. The expansion valve further includes a shape memory alloy actuator that exerts a force on the valve element towards an open valve position when the shape memory alloy actuator is heated by an electric current. An expansion valve for a vapour compression system of the above type may be controlled externally but also be self-regulating. The shape memory alloy actuator is arranged in a second fluid passage of the expansion valve and the shape memory alloy actuator is in thermal contact with fluid in the second fluid passage, such that the shape memory alloy actuator actuates the valve element towards a closed valve position when the shape memory actuator is cooled by the fluid.

Abstract: A method for controlling a vapour compression system (1) is disclosed, the vapour compression system (1) comprising at least one compressor (2, 16), a heat rejecting heat exchanger (3), a high pressure expansion device (4, 15, 17), a receiver (5), an evaporator expansion device (6), an evaporator (7) and a gas bypass valve (8), arranged in a refrigerant path. It is registered that the gas bypass valve (8) is malfunctioning or saturated, and a pressure value for a pressure prevailing inside the receiver (5) is obtained. Finally, the vapour compression system (1) is controlled in order to control a gaseous refrigerant supply to the receiver (5) to adjust the pressure prevailing inside the receiver (5) to reach a target pressure level.

Abstract: A valve arrangement comprising a valve housing, a valve inlet, a valve outlet and a diaphragm assembly for controlling a fluid flow through the valve housing from the valve inlet to the valve outlet, the diaphragm assembly comprising a diaphragm and a diaphragm plate at least partially covering the diaphragm, the diaphragm comprising one or more equalization holes passing through the diaphragm and the diaphragm plate comprising one or more equalization openings passing through the diaphragm plate, the equalization holes being aligned with the equalization openings. The diaphragm assembly comprises an engagement zone engaging the diaphragm in order to rotationally fix the diaphragm and the diaphragm plate with respect to each other so that the equalization holes will keep aligned with the equalization openings to ensure proper function of the valve arrangement at all times.

Abstract: A method for controlling a vapour compression system, the vapour compression system including a compressor unit with one or more compressors. At least one of the compressors is connectable to a gaseous outlet of a receiver, and at least one of the compressors is connectable to an outlet of an evaporator. A parameter of the vapour compression system is measured, an enthalpy of refrigerant leaving the heat rejecting heat exchanger being derivable from the measured parameter. A setpoint value for a pressure inside the receiver is calculated, based on the measured parameter, and the compressor unit is operated in accordance with the calculated setpoint value, and in order to obtain a pressure inside the receiver which is equal to the calculated setpoint value. The vapour compression system is operated in an energy efficient manner over a wide range of ambient temperatures.

Abstract: A method for operating a vapour compression system (1) comprising a heat recovery heat exchanger (4) is disclosed. The heat recovery system requests a required level of recovered heat to be provided by the heat recovery heat exchanger (4) to the heat recovery system, generates a signal indicating the required level of recovered heat, and supplies the generated signal to a control unit of the vapour compression system (1). A setpoint value for at least one control parameter of the vapour compression system (1) is calculated, based on the generated signal, and the vapour compression system (1) is operated in accordance with the calculated setpoint value(s).

Abstract: An example refrigerant system according to an exemplary aspect of this disclosure includes, among other things, a refrigerant loop having at least a condenser, an evaporator, and a compressor. The compressor includes a motor in communication with a variable speed drive. The system further includes a cooling circuit including a pressure regulator downstream of a heat exchanger, the heat exchanger absorbing heat from the variable speed drive.

Abstract: A method for controlling a vapour compression system in an energy efficient and stable manner, the vapour compression system (1) including at least two evaporator groups (5a, 5b, 5c), each evaporator group (5a, 5b, 5c) including an ejector unit (7a, 7b, 7c), at least one evaporator (9a, 9b, 9c) and a flow control device (8a, 8b, 8c) controlling a flow of refrigerant to the at least one evaporator (9a, 9b, 9c). For each evaporator group (5a, 5b, 5c) the outlet of the evaporator (9a, 9b, 9c) is connected to a secondary inlet (12a, 12b, 12c) of the corresponding ejector unit (7a, 7b, 7c).

Abstract: A method for attaching an object, such as a sight glass (3) or an electrical connector (4), to a structure, such as a valve housing (1), the object (3, 4) comprising an annular flange (6, 11). The object (3, 4) is mounted in an opening (7, 12) of the structure (1) with the annular flange (6, 11) in abutment with an annular edge (8, 13) of the opening (7, 12). The object (3, 4) is attached to the structure (1) by performing welding of the annular edge (8, 13) and the annular flange (6, 11) and displacing the welding beam along the annular flange (6, 11).

Abstract: The invention relates to an ejector arrangement (1, 40) comprising a housing (11) and at least two ejectors (2, 3, 41, 42) arranged in said housing (11) along a common axis (13). Each ejector (2, 3, 41, 42) has a motive inlet (4, 5), a suction inlet (6, 7), an outlet (8, 9) and a valve element (23, 24, 43, 44). The task of the invention is to provide an ejector arrangement that allows for a good control of the mass flow of fluid through the ejector arrangement while keeping the construction simple. According to the invention the above task is solved in that the ejector arrangement (1, 40) comprises a common actuator (25, 55), that is arranged to engage at least two of the valve elements (23, 24, 43, 44) to open the motive inlets (4, 5).

Abstract: A method of operating a reciprocating compressor for a vapour compression system is disclosed. The reciprocating compressor comprises at least two cylinders and at least two unloaders, each unloader can be operated in an idle mode or in an active mode and therefore the reciprocating compressor can run in more than two capacity states. The capacity states alternates periodically between states in such a way that a substantially continuous range of effective capacities can be obtained while the individual cylinders are evenly loaded.

Abstract: A method for controlling a vapour compression system having an ejector includes, in the case that a pressure difference between a pressure prevailing in the receiver and a pressure of refrigerant leaving the evaporator decreases below a first lower threshold value, the pressure of refrigerant leaving the heat rejecting heat exchanger is kept at a level which is slightly higher than the pressure level providing optimal coefficient of performance.

Abstract: The invention relates to a valve (1) comprising a main valve (2), a pilot valve (3), a housing (4), an inlet (5) and an outlet (8). Opening and closing of the main valve (2) is controlled by the pilot valve (3). A pilot valve seat (10) is arranged in a diaphragm (6). A pilot chamber (11) is arranged in the housing (4) separated from the inlet (5) and the outlet (8) by the diaphragm (6). Task of the invention is to provide a valve with a lower cost. According to the invention a support member (17) supports the diaphragm (6), wherein the support member (17) is guided in the housing, and wherein a radial gap (26) is arranged between the radially outer end of the diaphragm (6) and the housing (4) in a radial direction perpendicular to the opening direction of the pilot valve (3). Thereby, a cheaper, less resistant material for the diaphragm can be used.

Abstract: The axial bearing arrangement comprises a first axial bearing plate (12) and a second axial bearing plate (13) each having an annular ring shape, the first axial bearing plate (12) having a first surface (12.1) axially facing the second axial bearing plate (13) and a second surface (12.2) opposite to the respective first surface (12.1), the second axial bearing plate (13) having a first surface (13.1) axially facing the first axial bearing plate (12) and a second surface (13.2) opposite to the respective first surface (13.1); a spacer ring (14) clamped between the first surfaces (12.1, 13.1) of the first and second axial bearing plates (12, 13), the spacer ring (14) defining an axial distance between the first and second axial bearing plates (12, 13); and a bearing sleeve (15) abutting the second surface (13.2) of the second axial bearing plate (13) and being secured to a compressor block (16).

Abstract: A method for controlling a fan (6) of a vapour compression system (1) is disclosed, the fan (6) being arranged to provide a secondary fluid flow across a heat rejecting heat exchanger (3). A temperature difference, ?T=Tout?Tamb, between a temperature, Tout, of refrigerant leaving the heat rejecting heat exchanger (3) and a temperature, Tamb, of ambient air of the heat rejecting heat exchanger (3) is established. A setpoint value, ?Tsetp, for the temperature difference, ?T, is obtained, the setpoint value, ?Tsetp, being dependent on the fan speed of the fan (6) in such a manner that the setpoint value, ?Tsetp, increases as the fan speed increases. The fan speed of the fan (6) is controlled in order to control the temperature difference, ?T, in accordance with the obtained setpoint value, ?Tsetp.

Abstract: A hydraulic machine is described having a first part (2) and a second part (3) moveable relative to said first part (3), one of said first part (2) and said second part (3) having a first land (9) resting against the other one of said second part (3) and said first part (2), having a predetermined first height (H1), and being arranged between a high pressure area (7) and a low pressure area (8). Such a machine should have a long working life. To this end a second land (10) having a predetermined second height (H2) smaller than said first height (H1) is located adjacent to said first land (9).

Abstract: A method for controlling suction pressure in a vapour compression system (1) comprising one or more cooling entities (5) is disclosed. For each cooling entity (5), a maximum required suction pressure and/or a required change in suction pressure for maintaining a target temperature in the refrigerated volume is obtained. A most loaded cooling entity (5) among the one or more cooling entities (5) is identified, based on the maximum required suction pressures and/or the required changes in suction pressure. The suction pressure of the vapour compression system (1) is controlled in accordance with the maximum required suction pressure and/or required change in suction pressure for the identified most loaded cooling entity (5).

Abstract: A solenoid valve (1) is described comprising a first port (2), a second port (3), a valve element (4) and a valve seat (5) arranged between said first port (2) and said second port (3), a coil (12) and a yoke arrangement (14-16), said coil (12) being magnetically linked to said yoke arrangement (14-16), said yoke arrangement (14-16) having a movable armature (16). In such a solenoid valve the generation of noise should be kept low.

Abstract: A method for controlling a supply of refrigerant to an evaporator of a vapour compression system, such as a refrigeration system, an air condition system or a heat pump. During normal operation, the opening degree of the expansion valve is controlled on the basis of an air temperature, Tair, of air flowing across the evaporator and/or on the basis of superheat of refrigerant leaving the evaporator. If at least one sensor used for obtaining Tair or the superheat is malfunctioning, operation of the vapour compression system is switched to a contingency mode. A reference temperature, Tout, ref, is calculated, based on previously obtained values of a temperature, Tout, of refrigerant leaving the evaporator, during a predefined previous time interval, and subsequently the opening degree of the expansion valve is controlled on the basis of the obtained temperature, Tout, in order to reach the calculated reference temperature, Tout, ref.

Abstract: The centrifugal compressor includes an hermetic housing; a drive shaft (4); a first and a second compression stage (8, 9) configured to compress a refrigerant, the first and second compression stages (8, 9) respectively including a first and a second impeller (18, 19), the first and second impellers (18, 19) being connected to the drive shaft (4) and being arranged in a back-to-back configuration; a radial annular groove (27) formed between the back-sides (25, 26) of the first and second impellers (18, 19); an inter-stage sealing arrangement (35) provided between the first and second compressor stages (8, 9) and in the radial annular groove (27); a radial bearing arrangement configured to rotatably support the drive shaft (4); and a thrust bearing arrangement configured to limit an axial movement of the drive shaft (4) during operation.

Abstract: The invention relates to a pressure sensor (1) comprising a pressure sensing arrangement (8) and a housing. The housing comprises an intermediate member (2) and a bottom part (3), wherein the intermediate member (2) comprises an aperture (4). The aperture (4) extends through the intermediate member (2), wherein the aperture (4) is on a first end (5) covered by a diaphragm (6) connected to the intermediate member (2). A second end (7) of the aperture (4) is covered by the bottom part (3) comprising the pressure sensing arrangement (8). Task of the invention is to provide a pressure sensor which allows a simplified and cost effective assembly and mounting. The task is solved in that the intermediate member (2) comprises a gripping surface (16) on an outer surface of the housing.