Abstract: A heat exchanger plate (2) is described comprising an edge (7), a groove (8) running along the edge (7), a gasket arranged in the groove (8), and a corrugated area (10) having tops (12) and valleys (11) between the groove (8) and the edge (7), wherein tops (12) run substantially perpendicular to the edge (7). In such a heat exchanger plate the gasket should be reliably fixed without affecting the stability of the heat exchanger. To this end, in at least one valley (11) a raised section (14) extends from a bottom area (13) of the valley (11) and the gasket comprises a click-on extension arranged in the valley (11) and having a recess adapted to the raised section (14).

Abstract: The present invention relates to a plate-and-shell heat exchanger (100) having a stack of plate pairs (50, 60) positioned in a shell (20), where the stack of plate pairs (50, 60) includes a plurality of plate pairs of a first type (50) and a plurality of plate pairs of a second type (60). Each plate pair (50, 60) has two heat transfer plates (10) being connected to each other and forming a cavity (11) there between, and forming an inlet opening (13a, 13b) and an outlet opening (13?a, 13?b). First inner flow paths (12a) are formed through the first inlet openings (13a), the cavities (11) of the plate pairs of the first type (50) and the first outlets (13?a). Second inner flow paths (12b) are formed through the second inlet openings (13b), the cavities (11) of the plate pairs of the second type (60) and the second outlets (13?b). A third outer flow path (22) is defined within the shell and between plate pairs of the first type (50) and plate pairs of the second type (60).

Abstract: A heat exchanger plate (1) is described comprising an edge (2), a groove (3) running along the edge (2), and a corrugated area (4) having tops (5) and valleys (6) between the groove (3) and the edge (2), wherein the tops (5) run substantially perpendicular to the edge (2) and the groove (3) comprises an external wall (7) adjacent to the corrugated area (4) and an internal wall (8). Using such a heat exchanger plate (1) it should be possible to produce a reliable plate-type heat exchanger of simple construction. To this end the external wall (7) is in form of a wavy shape.

Abstract: A heat exchanger plate (1) is described comprising an edge (2), a groove (3) running along the edge (2), and a corrugated area (4) having tops (5) and valleys (6) between the groove (3) and the edge (2), wherein the tops (5) run substantially perpendicular to the edge (2) and the groove (3) comprises an external wall (7) adjacent to the corrugated area (4) and an internal wall (8). Using such a heat exchanger plate (1) it should be possible to produce a reliable plate-type heat exchanger of simple construction. To this end the external wall (7) is in form of a wavy shape.

Abstract: A plate-type heat exchanger is described comprising a stack of heat exchanger plates (2b) forming a first flow path and a second flow path, wherein each heat exchanger plate (2b) comprises an opening (7b) in an opening area (8b), the opening area (8b) being connected to one of the two flow paths and sealed against the other of the two flow paths by means of a gasket arrangement (11b). Such a plate-type heat exchanger should be suitable for high pressures without increasing the risk of leakages. To this end a support element (15) is arranged in the sealed opening area (8b).

Abstract: A heat exchanger plate (2) is described comprising an edge (7), a groove (8) running along the edge (7), a gasket arranged in the groove (8), and a corrugated area (10) having tops (12) and valleys (11) between the groove (8) and the edge (7), wherein tops (12) run substantially perpendicular to the edge (7). In such a heat exchanger plate the gasket should be reliably fixed without affecting the stability of the heat exchanger. To this end, in at least one valley (11) a raised section (14) extends from a bottom area (13) of the valley (11) and the gasket comprises a click-on extension arranged in the valley (11) and having a recess adapted to the raised section (14).

Abstract: The invention relates to a pump assembly with a pump and with an electrical drive motor, as well as an electronic control device. The electronic control device includes a rotation direction recognition module for recognizing the correct rotation direction (CW, CCW) of the drive motor and of the pump. The rotation direction recognition module detects at least one performance characteristic value (H, Q, P) of the pump assembly, and is designed in a manner such that on rotation of the drive motor, the rotation direction recognition module detects at least one performance characteristic value (H, Q, P) and determines the correct rotation direction (CW, CCW) by way of evaluation of the performance characteristic value (H, Q, P).

Abstract: The invention relates to a pump assembly with a pump (4) and with an electrical drive motor (6), as well as an electronic control device (8), wherein the electronic control device (8) comprises a rotation direction recognition module (14) for recognizing the correct rotation direction (CW, CCW) of the drive motor (6) and of the pump (4), the rotation direction recognition module comprising means (22, 24) for detecting at least one performance characteristic value (H, Q, P) of the pump assembly, and being designed in a manner such that on rotation of the drive motor (6), the rotation direction recognition module detects at least one performance characteristic value (H, Q, P) and determines the correct rotation direction (CW, CCW) by way of evaluation of the performance characteristic value (H, Q, P).

Abstract: The pump unit is provided, in particular for heating and cooling installations. The speed of the pump unit may be altered by changing the operating frequency of a frequency converter feeding the electric motor and which forms a structural unit with the pump unit. As soon as the pump unit has reached a parameter characterizing the thermal overload of the same, the frequency converter is controlled in a manner so as to reduce the speed, the reduced speed n' being greater or equal to half the normal speed n.

Abstract: The invention relates to a changeover discharge circuit for an electronic switching circuit of the type having a semiconductor switching element in series with a DC source and an inductive load. Initiation of the discharge current of a discharge capacitor is delayed upon the switching on of the switching element until the substantial termination of the load current by a commutation choke coil and a recovery diode in shunt with the load.