Abstract: A pump arrangement (1) is provided comprising a driving shaft (2), cylinder drum means (3a, 3b) fixed to said shaft (2) in rotational direction and having a plurality of cylinders (6a, 6b), and a piston (7a, 7b) in each cylinder, each piston (7a, 7b) having a slide shoe (8a, 8b) in contact with driving surface means (8a, 8b). Such a pump arrangement should produce a pressure with low undulations. To this end said cylinder drum means (3a. 3b) comprise at least a first cylinder drum (3a) and a second cylinder drum (3b), said cylinder drums (3a, 3b) being fixed to said common shaft (2) in rotational direction, wherein the cylinder drums (3a, 3b) are offset with respect to each other in rotational direction.

Abstract: The invention relates to an axial valve comprising an actuator (15) and a center tube (19). The actuator comprises a stationary element (16) and a closing element (17), and the center tube (19) is placed axially in relation to an axial extension of the stationary element (16). The center tube (19) is in a fixed position relative to the stationary element (16). Fluid, such as refrigerant, is intended for flowing through the valve and through the center tube. The center tube (19) comprises orifices (22) for fluid passage. The closing element (17) is placed axially to an axial extension of the center tube (19) and is movable axially along the center tube between a first position, where the closing element closes the orifices (22) of the center tube, thereby not allowing fluid to pass the orifices, and a second position, where the orifices (22) are open, thereby allowing fluid to pass the orifices.

Abstract: A valve actuator device (1) for a heating or cooling system valve (2) includes a motor (10) and control means (11), said motor (10) driving actuating means (8) provided for actuating a valve element (6), said control means (11) comprising presetting means (14) for performing a presetting function. The operation possibilities of such a valve actuator device should be increased. To this end, said control means comprise flushing means for performing a flush function, said flush function overriding said presetting function.

Abstract: A method for controlling a vapor compression system, such as a refrigeration system, preferably an air condition system, comprising at least two evaporators. While monitoring a superheat (SH) at a common outlet for the evaporators, the amount of available refrigerant is controlled in response to the SH and in order to obtain an optimum SH value. The available refrigerant is distributed among the evaporators in accordance with a distribution key. The distribution key is preferably obtained while taking individual consideration to operating conditions for each of the evaporators into account. Thereby the vapor compression system can be operated in such a way that each of the evaporators is operated in an optimal manner, and in such a way that the system in general is operated in an optimal manner.

Abstract: A micro-channel heat exchanger includes an inlet manifold fluidly connected with an outlet manifold by a plurality of generally parallel tubes, further defining a plurality of generally parallel micro-channels therethrough. Refrigerant is introduced to the heat exchanger through a distributor tube disposed within the inlet manifold. The distributor tube includes a plurality of non-circular openings disposed along the length thereof which act as an outlet for refrigerant flow into the inlet manifold and eventually into and through the tubes and micro-channels. The openings are preferably slots arranged along the length of the distributor tube at an angle relative to the longitudinal direction of the distributor tube and oriented within the inlet manifold for a general direction of refrigerant flow at an angle relative to the general direction of refrigerant flow through the tubes. Alternative shapes for the openings are also considered.

Abstract: A valve comprising an inlet opening adapted to receive fluid medium and at least two outlet openings, each being fluidly connected to a flow path being arranged fluidly in parallel, is disclosed. The valve comprises a first valve part (1) and a second valve part (3). The first valve part (1) has at least two flow passages (2) formed therein, each flow passage (2) being fluidly connected to one of the outlet openings. The second valve part (3) has at least one primary flow passage (4) and at least one secondary flow passage (5, 6, 7) formed therein, the primary flow passage(s) (4) and the secondary flow passage(s) (5, 6, 7) being fluidly connected to the inlet opening.

Abstract: The invention concerns a vane cell machine with a stator and a rotor having radially displaceable vanes arranged in guides, said vanes bearing on an inside of the stator and bordering, together with the rotor, the stator and a side wall, work chambers at each axial end of the rotor. It is endeavored to provide a vane cell machine that has a good internal tightness, in which the wear is still kept small. For this purpose, in a radially internal area the side wall comprises an insert that is axially movable in the side wall and has a pressure application surface axially inside and axially outside.

Abstract: The present invention relates to a method and a system to reduce losses of energy due to ripples, especially at the power grid, the ripples being short term power shortages or excess power. The method is based on the idea of shutting off energy consuming devices during a period of power shortage, if their operation is not necessary, and optionally to turn on such energy consuming devices during periods of excess power, if energy may be stored in them, especially when energy may be stored as some physical parameter or variable, being a part of the operation of the energy consuming devices, such as the temperature of a freezer.

Abstract: A method for operating a vapor compression system is disclosed. The vapor compression system comprises a compressor, a condenser, at least one expansion device, an evaporator, said evaporator comprising at least two evaporator paths arranged fluidly in parallel, and a distribution device arranged to distribute refrigerant among the evaporator paths. The method comprises the steps of obtaining at least two predefined distribution keys, each distribution key defining a distribution of available refrigerant among the evaporator paths, detecting one or more operational settings of the vapor compression system, selecting one of the at least two predefined distribution keys, based on said detected operational setting(s), and distributing refrigerant among the evaporator paths in accordance with the selected predefined distribution key.

Abstract: A heat exchanger is provided comprising a stack of heat exchanger plates (1, 1a, 1b, 1c) formed of sheet metal having a three-dimensional structured pattern (2, 3), each heat exchanger plate (1,1a, 1b, 1c) having a groove (10), a gasket (9) being arranged in said groove (10) and resting against an adjacent heat exchanger plate (1a), said groove (10) having a bottom inner surface (11), said inner surface bottom (11) having at least a protrusion (14, 15) directed to said adjacent heat exchanger plate (1a). It is intended to minimize the risk of a leakage. To this end in the region of said protrusion (14, 15) said gasket (9) is compressed more than in a region out of said protrusion (14, 15).

Abstract: A magnetic valve (1) comprising a valve housing (2) defining an inlet opening (3) and an outlet opening (4), a valve seat (11), a valve closing element, and an armature tube (7) is disclosed. A piston (6) is arranged movably inside the armature tube (7), said piston (6) being connected to the valve closing element, and an armature (5) is arranged movably at least partly inside the piston (6). A coil (9) is arranged externally to the armature tube (7) in such a manner that at least a part of the armature (5) arranged inside the piston (6) is arranged inside the windings of the coil (9).

Abstract: A refrigeration system includes an expansion valve and a compressor, the expansion valve, the evaporator and the compressor being arranged in a refrigerant flow path having refrigerant flowing therein. A method for controlling a flow of refrigerant to an evaporator includes steps of increasing an opening degree of the expansion valve, thereby increasing a flow of refrigerant to the evaporator sufficiently to substantially eliminate a dry zone of the evaporator, decreasing the opening degree of the expansion valve, and repeating the steps of increasing and decreasing. This causes the superheat value of refrigerant leaving the evaporator to ‘toggle’ between a zero level and a low, but positive, level. Thereby the refrigeration capacity is utilized more efficiently. Additionally, sufficiently low amount of liquid refrigerant is allowed to pass through the evaporator to prevent damage to the compressor.

Abstract: A refrigerant compressor includes a housing providing a refrigerant outlet having a throat. An electric motor is provided in the housing to directly drive an impeller via a shaft about an axis in response to a variable speed command. The impeller includes an outlet end aligned with variable geometry diffuser. A magnetic bearing assembly rotationally supports the shaft relative to the housing in response to a magnetic bearing command. A member is arranged to adjust the throat area, and which can move in a direction generally parallel to the axis in response to an actuator receiving a compressor regulation command. A controller is configured to respectively provide the variable speed command, the magnetic bearing command and the compressor regulation command to the electric motor to vary throat area, the magnetic bearing assembly and the actuator to obtain a desired compressor operation without the need of variable inlet geometry.

Abstract: The invention relates to a thermal energy storage system comprising at least one thermal reservoir and at least one thermal energy transfer means that, at least at times, are able to transfer thermal energy from at least one first section of the thermal reservoir to at least one second section of the thermal reservoir. The invention also relates to a method changing the energy distribution of a thermal reservoir wherein thermal energy is transferred from at least one first section of the thermal reservoir to at least one second section of the thermal reservoir.

Abstract: An expansion valve for a vapor compression system comprises a first valve member and a second valve member. The first valve member and the second valve member are arranged movably relative to each other, and the relative position of the first valve member and the second valve member determines an opening degree of the expansion valve. The first valve member and/or the second valve member is/are automatically movable in response to changes in a differential pressure across the expansion valve, the opening degree of the expansion valve thereby being automatically altered in response to changes in the differential pressure across the expansion valve. It is ensured that the opening degree of the expansion valve is automatically adjusted to the actual operating conditions, thereby optimising the efficiency of the vapour compression system.

Abstract: This disclosure relates to a centrifugal compressor. In a first example, the compressor includes a first impeller provided in a main refrigerant flow path, a second impeller provided in the main refrigerant flow path downstream of the first impeller, and a recirculation flow path. In the first example, the recirculation flow path is provided between a first location and a second location along the main refrigerant flow path. The first location is downstream of the second location, and the second location is downstream of the first impeller. In a second example, the compressor includes an impeller provided in a main refrigerant flow path, and a recirculation flow path provided between a first location and a second location along the main refrigerant flow path. In the second example, the recirculation flow path includes a recirculation volute. Further disclosed is a method for operating a centrifugal compressor.