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: The invention concerns a valve arrangement (7) comprising a flow path (11) connecting an inlet (9) and an outlet (10), a closing means (12) arranged in said flow path (11), a resetting means and a first pressure in a first pressure chamber (14) acting in a closing direction on said closing means (12), a pressure of said outlet (10) and a second pressure in a second pressure chamber (18) corresponding to a pressure of said inlet (9) when said closing means (12) is closed acting in opening direction on said closing means (12), said first pressure chamber (14) being connectable to the outlet (10) via an auxiliary valve (13). It is intended to keep small a pressure pulse when opening the valve arrangement (7). This is achieved in that the closing means (12) having a first opening state (A) and a second opening state (B), a flow resistance of said closing means (12) in said first opening state (A) being larger than a flow resistance of said closing means in said second opening state (B).

Abstract: A compressor and a method of assembling the compressor are provided. The compressor includes: a shell; a motor arranged in the shell, the motor having a stator, a spacer mounted with a first bearing therein, a drive shaft supported by the first bearing and a rotor fixed onto the drive shaft; a low bearing support; a positioning member positioning the second bearing and being connected to the low bearing support; and a second bearing connected to the positioning member and/or the low bearing support and supporting the drive shaft. Furthermore, the positioning member may be removed from or maintained in the compressor after it is assembled. The present invention can avoid the adverse effects of the gravity of the rotor and the drive shaft and/or the magnetic force between the rotor and the stator on positioning the bearings and the drive shaft and can improve positioning accuracy and assembling efficiency.

Abstract: This compression device comprises first and second compressors mounted in parallel, a suction line intended to be connected to an outlet of an evaporator, first and second suction conduits arranged for putting the suction line respectively in communication with the admission orifices of the first and second compressors, and an oil level equalization conduit connecting the oil pans of the first and second compressors. The compression device further comprises an oil separator mounted on the suction line or on the second suction conduit, and an oil return conduit arranged for connecting an oil outflow orifice of the oil separator to the oil pan of the first compressor.

Abstract: The invention relates to a neutral setting device of an adjustable hydraulic machine, in particular the adjustment of the neutral setting of a servo valve. The present invention relates in particular to servo adjustment devices with mechanically adjustable control pistons, wherein the necessary force can be applied mechanically, electromagnetically, pneumatically or hydraulically. The invention relates to a neutral setting device of an adjustable hydraulic machine with a housing in which a mounted input shaft is arranged, at which on one end a torque can be applied for turning the input shaft around an axis. On a second end a cylindrical extension is arranged eccentrically parallel to the axis. An adjustable control piston for opening and closing hydraulic fluid openings for application of pressure of a servo piston adjusts the hydraulic machine with respect to its delivery volume.

Abstract: The oil injection device according to the invention includes an oil pump designed to be rotationally coupled to the electric motor of a compressor and including inlet and outlet ports, an oil injection duct connected to the first outlet port and designed to supply a compression stage of the compressor with oil, and an oil return duct connected to the first outlet port and designed to return the oil into an oil sump of the compressor. The pressure losses in the oil injection duct are primarily singular pressure losses proportional to the square of the oil flow rate passing through the oil injection duct. The pressure losses in the oil return duct are primarily pressure losses due to friction proportional to the oil flow rate passing through the oil return duct.

Abstract: The compressor includes a sealed enclosure containing a compression stage, an electric motor having a stator and a rotor, an oil pump rotationally coupled to the rotor, including an oil inlet port connected to an oil sump, and control means arranged to command the operation of the motor in a start-up mode in which the rotor is rotated at a first speed of rotation included in a first speed range, and a normal operating mode in which the rotor is rotated at a second speed of rotation included in a second speed range higher than the first speed range. The compressor includes an oil injection device having an oil injection duct connected to a first oil outlet port of the oil pump and arranged to supply the compression stage with oil.

Abstract: The scroll refrigeration compressor according to the invention includes a sealed enclosure at least partially defining a discharge chamber designed to be connected to a discharge line, and a discharge valve attached on the sealed enclosure and fluidly connected to the discharge chamber. The discharge valve includes a valve body, a valve seat, and a discharge check valve movable between a covering position and a released position. The discharge valve includes deflection means positioned in the valve body and arranged to orient the flow of refrigerant coming from the discharge line at least partially toward the periphery of the discharge check valve.

Abstract: A compression device includes a first compressor and a second compressor mounted in parallel, each compressor including a leakproof enclosure including a low pressure portion containing a motor and an oil sump, an oil level equalization conduit putting into communication the oil sumps of the first and second compressors, and control means adapted for controlling the starting and the stopping of the first and second compressors. The first compressor includes first detection means coupled with the control means and adapted for detecting an oil level in the oil sump of the first compressor. The control means are adapted for controlling the stopping of the second compressor when the oil level detected by the first detection means falls below a first predetermined value.

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 endeavoured 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 refrigeration compressor according to the invention includes a sealed enclosure containing a compression stage and provided with a refrigerant inlet and outlet, the compressor being configured such that under usage conditions, a flow of refrigerant circulates through the refrigerant inlet, the compression stage, and the refrigerant outlet. The compressor has an oil pan and oil recirculation means arranged to orient the oil contained in the oil pan into the flow of refrigerant when the oil in the oil pan exceeds a predetermined oil level. The recirculation means include a recirculation line housed in the sealed enclosure and including an inlet port situated at a height substantially corresponding to the predetermined oil level, an outlet port emerging in the refrigerant flow, and an intermediate part connecting the inlet and outlet ports. The intermediate part includes a first portion extending below the predetermined oil level.

Abstract: In open-circuit hydraulic systems (1), the cross-sections of the supply lines (6) and input valves of the hydraulic pump (3) have to be large, so that sufficient flow flux can be provided. This hinders a reduction of the size of the pump and the whole hydraulic system. It is suggested that the supply flow (7) of a hydraulic pump (3) is charged by a second, charging pump (2), to a mid-pressure level (7). The cross-sections of the supply flow areas can thus be decreased.