Abstract: A method for controlling a variable capacity ejector unit (7) arranged in a refrigeration system (1) is disclosed. An ejector control signal for the ejector unit (7) is generated, based on an obtained temperature and an obtained pressure of refrigerant leaving a heat rejecting heat exchanger (3), or on the basis of a high pressure valve control signal for controlling an opening degree of a high pressure valve (6) arranged fluidly in parallel with the ejector unit (7). The ejector control signal indicates whether the capacity of the ejector unit (7) should be increased, decreased or maintained. The capacity of the ejector unit (7) is controlled in accordance with the generated ejector control signal. The power consumption of the refrigeration system (1) is reduced, while the pressure of the refrigerant leaving the heat rejecting heat exchanger (3) is maintained at an acceptable level.

Abstract: A pump device (1) is provided comprising: a shaft (2), rotor means (3a, 3b) fixed to said shaft (2) in rotational direction, said rotor means (3a, 3b) having pressure chambers (5a, 5b) the volume of which varying during a rotation of said rotor means (3a, 3b), port plate means (15a, 15b) having a through going opening (16a, 16b) for each of said pressure chambers (5a, 5b) and being connected to said rotor means (3a, 3b) in rotational direction, and valve plate means (17a, 17b) cooperating with said port plate means (15a, 15b). It is intended to pressurize a high volume of fluid, in particular water, within a limited space.

Abstract: A valve (9) for use in a vapour compression system (1) is disclosed. The valve (9) comprises a first inlet (13) arranged to be connected to a gaseous outlet (11) of a receiver (6), a second inlet (14) arranged to be connected to an outlet of an evaporator (8), a first outlet (15) arranged to be connected to an inlet of a compressor unit (2), a non-return valve arrangement (19) arranged to allow a fluid flow from the second inlet (14) towards the first outlet (15), but to prevent a fluid flow from the first outlet (15) towards the second inlet (14), and a control valve mechanism (20) arranged to control a fluid flow from the first inlet (13) towards the first outlet (15).

Abstract: A level sensor is configured to provide a receiver level indicating an amount of the refrigerant present in the receiver and a level model provides a heat rejecting heat exchanger estimate indicating an amount of the refrigerant present in the heat rejecting heat exchanger based on a temperature of the refrigerant. From the sensor and the model, a loss of refrigerant from the refrigerant vapor compression system is estimated.

Abstract: This disclosure relates to a control system and method for the centrifugal compressor. The system, for example, includes a controller configured command an adjustment of at least one of (1) a flow regulator and (2) a speed of a shaft in order to provide safe, efficient compressor operation. Centrifugal compressors are used to circulate refrigerant in a chiller via a refrigerant loop. Centrifugal compressors operate efficiently before reaching a condition known as surge.

Abstract: A bulb (5) for a thermostatic expansion valve is provided, said bulb (5) comprising a chamber (7), said chamber (7) being located within a metallic casing of said bulb and being filled with a filling adapted to influence a valve element of said thermostatic expansion valve. Service of a temperature controlled valve connected to a bulb should be facilitated. To this end said bulb (5) comprises a connection geometry (10) adapted to be connected to a capillary member (6) and said casing being provided with a closed opening zone located within said connection geometry (10), said opening zone being adapted to be opened upon mounting a counterpart (15) to said connection geometry (10).

Abstract: A method for controlling a vapor compression system (1) is disclosed, the vapor compression system (1) comprising an ejector (5). The method comprises controlling a compressor unit (2) in order to adjust a pressure inside a receiver (6), on the basis of a detected pressure of refrigerant leaving an evaporator (8). The portion of refrigerant leaving the evaporator (8) which is supplied to a secondary inlet (15) of the ejector is maximized and the portion of refrigerant supplied directly to the compressor unit (2) is minimized, while ensuring that the pressure of refrigerant leaving the evaporator (8) does not decrease below an acceptable level.

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 surfacebottom (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 vapour compression system (1) includes an ejector (6) and a liquid separating device (10) arranged in a suction line. At least one evaporator (9) is allowed to be operated in a flooded state. A flow rate of refrigerant from the liquid separating device (10) to the secondary inlet (15) of the ejector (6) is detected, and it is determined whether or not the flow rate is sufficient to remove liquid refrigerant produced by the evaporator(s) (9) from the liquid separating device (10). In the case that it is determined that the flow rate of refrigerant from the liquid separating device (10) to the secondary inlet (15) of the ejector (6) is insufficient to remove liquid refrigerant produced by the evaporator(s) (9), the flow rate of refrigerant from the liquid separating device (10) to the secondary inlet (15) of the ejector (6) is increased, and/or a flow rate of liquid refrigerant from the evaporator(s) (9) to the liquid separating device (10) is decreased.

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: A valve arrangement according to the present disclosure includes a valve module and a drain valve. The valve module includes first and second functional spaces, and an attachment interface defining a passage into one of the first or second functional spaces. The drain valve includes a fluid inlet and a fluid outlet formed through a common connector part that is connectable to the attachment interface to connect the fluid inlet of the drain valve to the second functional space and the at least one fluid outlet to the first functional space.

Abstract: The invention relates to a plate heat exchanger (9) with a plurality of heat exchanger plates (1, 13), each comprising at least one section showing indentations (2, 3, 14, 15), intended to be placed against corresponding indentations (2, 3, 14, 15) of a heat exchanger plate (1, 13) of a corresponding design. The heat exchanger (9) has a first type of indentations (2, 14) and a second type of indentations (3, 15), wherein the number of said first type of indentations (2, 14) and said second type of indentations (3, 15) are differing.

Abstract: The invention relates to a pilot valve arrangement (1) comprising a pilot valve device (2) which comprises a pilot valve element (13), a pilot valve seat (14) cooperating with the pilot valve element (13) and a presetting mechanism for presetting an opening pressure of the pilot valve element (13), the pilot valve arrangement (1) further comprising a presetting mechanism actuating device (3) which comprises an actuator element (17) adapted to create an actuating force in order to actuate the presetting mechanism in the pilot valve device so as to preset the opening pressure. According to the invention, the pilot valve arrangement (1) comprises a contactless force coupling arrangement adapted to transfer the actuating force from the presetting mechanism actuating device (3) to the pilot valve device (2). An inventive pilot valve device (2) is disclosed and claimed as well. The invention allows to improve maintenance and safety concerning the devices mentioned above.

Abstract: The invention relates to an actuator for a valve in a refrigeration system. The invention also relates to a valve with such actuator, and to a refrigeration system with such valve. The actuator comprises an elongated Shape Memory Alloy (SMA) element extending along two or more string-like extensions from a distant end to a proximate end in relation to a valve element of a valve. The SMA element, when forming part of the valve, may extend from the distant end to the proximate end connected to a housing of the SMA element, however, electrically insulated from the housing. An encapsulation may provide a thermal resistance, a thermal conductor and/or an electrical resistance between the SMA element and other elements or the surroundings of the SMA element.

Abstract: A hydraulic device 1 comprises a first member 2 movable relative to a second member 5. In such a device the risk of cavitation noise and cavitation damage should be minimized. To this end said first member 2 having a pressure chamber 3 opening in a face 7 of said first member 2 which face 7 is in contact with a contact face 6 of said second member 5, said second member 5 having a low pressure area 9, wherein a throttling flow path is provided in a groove 11 connecting said pressure chamber 3 and said low pressure area 9 when pressure chamber 3 is approaching said low pressure area 9, characterized in that a throttling resistance of said groove 11 increases in a direction of the flow through said groove 11.

Abstract: A vane cell machine is provided comprising a housing having a stator bore with an outer limitation formed by a circumferential wall and two axial end faces (5), a rotor mounted rotatably in said stator bore, a plurality of vanes moveable in radial direction relative to said rotor and sliding along said circumferential wall, and sealing means (12) at least at one of said end faces (5), said sealing means (12) acting on said rotor in axial direction. Such a vane cell machine should have a simple construction. To this end said end face (5) is formed at an end plate (11) of said housing wherein said end plate (11) comprises a recess in which said sealing means (12) are rotated.