Abstract: The invention provides a servo valve with a main piston and a servo piston. The servo piston controls a pressure in a servo chamber and thereby controls movement of the main piston based on a pressure difference between two chambers of the valve. To facilitate opening of the valve by relatively small pressures even in high pressure systems, the servo chamber according to the invention is provided inside the armature.

Abstract: The invention concerns a refrigerant compressor (1), particularly a semi-hermetic refrigerant compressor, with a housing (2), having in its bottom part (3) an oil sump (4), a compressor block (5) having at least one cylinder (6), in which a piston (7) is arranged, a crankshaft (11), which is supported in the compressor block (5) and in driving connection with the piston (7), and an oil pump arrangement (27), which is at least partly submerged in the oil sump. Also with varying speeds, good oil lubrication must be ensured. For this purpose, the crankshaft (11) has at its lower end a diameter extension (19), through which an oil channel (35) extends eccentrically to the crankshaft axis (36), said channel (35) connecting the oil pump arrangement (27) to a closed oil pressure chamber (21) between the crankshaft (11) and the compressor block (5), said chamber (21) being connected to the inside (37) of the housing (2) via a vent path (40, 41).

Abstract: A method of analysing a refrigeration system (1) comprising at least one compressor (4), at least one condenser (5) and at least two refrigeration entities (2), each comprising at least one evaporator (9). Based on information relating to the gas production by the evaporators (9) it is determined whether or not two or more evaporators (9) are running in a synchronized manner, i.e. are switching between an active and an inactive state at least substantially simultaneously. In case two or more evaporators (9) are running in a synchronized manner, the refrigeration system (1) may be controlled in order to desynchronize the evaporators (9). This may, e.g., be done by changing a cut-in temperature and/or a cut-out temperature for one of the corresponding refrigeration entities (2). Synchronization causes undesired variations in the suction pressure, and preventing synchronization therefore results in a more appropriate control of the refrigeration system (1). Reduces wear on the compressors (4).

Abstract: An actuator assembly for actuating a valve includes an extensible bellow having an open end and a closed end, a stem operable to contact the closed end and to actuate a stopper mechanism, and a driver configured to move the bellow. The movement of the bellow effects movement of the stem to actuate the valve. In one embodiment, the driver acts to compress the bellow, the compression causing movement of the stem to open the valve. The bellow may be hermetically sealed to the valve housing, thereby allowing a higher range of fluid pressures.

Abstract: An expansion valve (1) is disclosed which comprises an inlet opening (2), at least one outlet opening (3) and first and second valve parts. The inlet opening (2) is adapted to receive fluid medium in a liquid state. The outlet opening(s) (3) is/are adapted to deliver fluid medium in an at least partly gaseous state to a flow path. The valve parts are arranged movable relative to each other in such a manner that the mutual position of the first valve part and the second valve part determines a fluid flow between the inlet opening (2) and the outlet opening(s) (3). During normal operation, a resulting force acts upon the first valve part and/or the second valve part to press the first and second valve parts towards each other. The expansion valve (1) comprises means for reducing the resulting force acting upon the valve part(s). Thereby the valve parts can easier be moved relative to each other, and the force required in order to operate the valve (1) is thereby reduced.

Abstract: A method of visually investigating a coated surface of an object, the coating comprising a metal or an alloy, in order to determine whether or not the coating is tight. An increasing potential is applied to the object until a desired current level has been obtained or until a maximum potential has been reached. In case the coating is tight this results in a change in color of the coating. This may be due to a polarization of the coating material and/or due to an increase in thickness of a naturally occurring metal oxide layer. In case the coating is tight the desired current level can not be obtained, and the potential is increased to the maximum level resulting in a change in color. In case pinholes are present it is possible to obtain the desired current level, and the increase in potential is stopped before it is high enough to cause the change in color. Provides a dramatic visual effect allowing an immediate determination of whether or not pinholes are present.

Abstract: A method for calibrating a superheat sensor (5) for a refrigeration system is provided. The method comprises the following steps. Increasing an amount of liquid refrigerant in the evaporator (1), e.g. by increasing an opening degree of the expansion valve (3). Monitoring one or more parameters, e.g. the temperature of refrigerant leaving the evaporator (1), said parameters reflecting a superheat value of the refrigerant. Allowing the value of each of the parameter(s) to decrease. When the value(s) of the monitored parameter(s) reaches a substantially constant level, defining the superheat value corresponding to the constant level to be SH=0. The superheat sensor (5) is then calibrated in accordance with the defined SH=0 level. When the parameter(s) reaches the substantially constant level it is an indication that liquid refrigerant is allowed to pass through the evaporator (1), and thereby that the superheat of the refrigerant leaving the evaporator (1) is zero.

Abstract: A method for controlling a flow of refrigerant to an evaporator (1) arranged in a refrigeration system is disclosed. The refrigeration system further comprises an expansion valve (12) and a compressor, the expansion valve (12), the evaporator (1) and the compressor being arranged in a refrigerant flow path having refrigerant flowing therein. The method comprises the steps of increasing an opening degree of the expansion valve (12), thereby increasing a flow of refrigerant to the evaporator (1) sufficiently to substantially eliminate a dry zone (3) of the evaporator (1), decreasing the opening degree of the expansion valve (12) after a period of time has lapsed, and repeating the steps of increasing and decreasing the opening degree of the expansion valve (12). Thus, the opening degree of the expansion valve (12) is ‘pulsated’. This causes the superheat value of refrigerant leaving the evaporator (1) to ‘toggle’ between a zero level and a low, but positive, level.

Abstract: The invention concerns a reverse osmosis system (1) with a membrane unit (2) comprising an inlet (3), a permeate outlet (4) and a concentrate outlet (5), a high-pressure pump (8) that is connected to the inlet (3), a pressure exchanger (11) connected on its concentrate side (10) to the concentrate outlet (5), and a booster pump between the pressure exchanger (11) and the inlet (3). It is endeavoured to make the energy consumption as small as possible. For this purpose, the booster pump is made as a displacement pump.

Abstract: A superheat sensor (1) for sensing superheat of a fluid flowing in a flow channel (3) is disclosed. The sensor (1) comprises a flexible wall defining an interface between an inner cavity (5) having a charge fluid (6) arranged therein and the flow channel (3). The flexible wall is arranged in the flow channel (3) in thermal contact with the fluid flowing therein, and the flexible wall is adapted to conduct heat between the flow channel (3) and the inner cavity (5). Thereby the temperature of the charge fluid (6) adapts to the temperature of the fluid flowing in the flow channel (3), and the pressure in the inner cavity (5) is determined by this temperature. A first wall part (7, 14) and a second wall part (9, 16) are arranged at a variable distance from each other, said distance being defined by a differential pressure between the pressure of the charge fluid (6) and the pressure of the fluid flowing in the flow channel (3), i.e.

Abstract: A method of analyzing a refrigeration system (1) comprising at least one compressor (4), at least one condenser (5) and at least two refrigeration entities (2), each comprising at least one evaporator (9). Based on information relating to the gas production by the evaporators (9) it is determined whether or not two or more evaporators (9) are running in a synchronized manner, i.e. are switching between an active and an inactive state at least substantially simultaneously. In case two or more evaporators (9) are running in a synchronized manner, the refrigeration system (1) may be controlled in order to desynchronize the evaporators (9). This may, e.g., be done by changing a cut-in temperature and/or a cut-out temperature for one of the corresponding refrigeration entities (2). Synchronization causes undesired variations in the suction pressure, and preventing synchronization therefore results in a more appropriate control of the refrigeration system (1). Reduces wear on the compressors (4).

Abstract: The invention concerns a control cabinet arrangement (1) with a control cabinet (2), a mounting plate (6) having a front face (14), a rear face (13) and an opening (8), in which the control cabinet (2) is arranged, a frame and a retainer device. The invention is based on the task of providing a simple assembly of a control cabinet arrangement. For this purpose, the retainer device comprises several bolts (16) abutting the rear face (13) of the mounting plate (6), at least one bolt (16) being displaced into a spacing on the rear face (13) of the mounting plate (6) by the interaction of the control cabinet (2) and the frame (7).

Abstract: A tubular elastomer actuator with a shape in a cross-sectional view which shape exposes at most one single axis of symmetry of a specific length, e.g., an oval shape. The actuator could be made from a sheet made from a plurality of plate shaped elements which are laminated together and rolled. Each plate shaped element may have a corrugation that gives the element an anisotropic structure, and contains an electrode on only one surface. The actuator displacement is the result of shrinkage displacement of the plate shaped elements upon the application of electrical field across their thickness.

Abstract: Motor start circuit for an induction motor, particularly a single-phase AC induction motor, with a main winding (4) and an auxiliary winding (5), which are supplied with current, particularly alternating current, via current supply connections (24, 25), and with a start switching device (15) serving the purpose of interrupting the current flow through the auxiliary winding (5) after the start of the motor, the start switching device (15) being connected to a control device (20) via a connector (18), the control device (20) being connected between the current supply connections (24, 25), and with a winding protection switch (28), which is normally closed and which opens on the occurrence of a fault. The invention is characterized in that the control device (20) is connected to the winding protection switch (28) via at least one further connector (22, 17), preferably via at least one further connector (22, 17) and the auxiliary winding (5).

Abstract: The invention concerns a hydraulic piston machine, in particular a water hydraulic machine, with at least one cylinder, in which a piston (4) is arranged to reciprocate, the piston (4) comprising a hollow that is surrounded by an annular wall and has one open end. It is endeavoured to keep cavitations small. For this purpose, a filling member (13) is arranged in the hollow (12), the filling member (13) having at least a radial projection (22) and the annular wall (16) having at least a radial depression (17) in the inside facing the hollow (12), or the annular wall (16) having a radial projection and the filing member (13) having a radial depression, the depression having a restraint (19), at least at the end adjacent to the open end (18) of the hollow (12), and the projection (22) and the depression (17) engaging each other.

Abstract: An improved method for detection of engine faults especially suited for use on ships. The method is in particular related to the detection of a fault in an internal combustion engine having within the housing a crankshaft connected to a piston. The method includes determination of a pressure difference between the housing and the area outside the housing. If comparison of the pressure difference with a fault indicating pressure difference limit shows that the pressure difference is greater than the fault indication pressure difference limit then the presence of the fault is indicated. According to the method is in the pressure difference determined by comparing the pressure existing in the housing with the pressure of the area outside the housing, while attenuating pressure changes of the area outside the housing, so that pressure changes having a duration equal to or less than a defined fault characteristic period of time are supposed.

Abstract: A composite for a transducer facilitates an increased actuation force as compared to similar prior art composites for transducers. The composite facilitates increased compliance of the transducer in one direction, an improved reaction time as compared to similar prior art composites for transducers, and provides an increased lifetime of the transducer in which it is applied.