Clamping assembly having a pressure element

Abstract

A clamping assembly includes a configuration of mechanically clamped components disposed one on top of the other to form a stack. A clamping device generates a mechanical compressive force on the configuration of the components and a pressure element transmits the mechanical compressive force from the clamping device to the configuration. The pressure element contains a metal foam for a planar, homogeneous transmission of the compressive force. A sub module of a converter having at least one series circuit of power semiconductor switching units implemented as the clamping apparatus is also provided.

Claims

1. A clamping assembly, comprising: a configuration of mechanically clamped components positioned above one another in a stack; a clamping device for generating a mechanical compressive force on said configuration of said components; and a pressure element for transferring the mechanical compressive force from said clamping device to said configuration, said pressure element containing a metal foam material, said pressure element being conical.

2. The clamping assembly according to claim 1, wherein said metal foam material is one of a plurality of metal foam materials with different elastic properties in said pressure element.

3. The clamping assembly according to claim 1, wherein said configuration includes a semiconductor element.

4. The clamping assembly according to claim 3, wherein said configuration includes at least one cooling plate formed of conductive material, said at least one cooling plate lying against said semiconductor element and providing an electrical contact between said semiconductor element and said at least one cooling plate.

5. The clamping assembly according to claim 4, wherein said semiconductor element is one of a plurality of semiconductor elements of said configuration, at least one cooling plate is associated with each respective semiconductor element, and said semiconductor elements form an electrical series circuit.

6. The clamping assembly according to claim 5, wherein two cooling plates are associated with each respective semiconductor element and are disposed on both sides of said semiconductor element.

7. A sub module of a converter, the sub module comprising: at least one series circuit of power semiconductor switching units; each of said power semiconductor switching units including a respective power semiconductor configured to be switched on and off and configured to have the same forward conduction direction; said power semiconductor switching units being conductive in a direction opposite to said forward direction; an energy storage device connected in parallel with said at least one series circuit; and said at least one series circuit being implemented as a clamping apparatus according to claim 1.

8. A clamping assembly, comprising: a configuration of mechanically clamped components positioned above one another in a stack; a clamping device for generating a mechanical compressive force on said configuration of said components; and a pressure element for transferring the mechanical compressive force from said clamping device to said configuration, said pressure element containing a metal foam material, said metal foam material being one of a plurality of metal foam materials with different elastic properties in said pressure element; said configuration having an inside and an outside disposed along a central axis, said metal foam materials in said pressure element forming partial regions, and said partial regions each having a different stiffness rising from said inside to said outside along said central axis of said configuration.

9. The clamping assembly according to claim 8, wherein said central axis extends in a clamping direction of the clamping assembly.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) The invention is explained below in more detail with reference to an exemplary embodiment illustrated in FIGS. 1 to 2.

(2) FIG. 1 shows a schematic representation of a cross-section of an exemplary embodiment of a clamping assembly according to the invention.

(3) FIG. 2 shows a schematic representation of an exemplary embodiment of a sub module according to the invention.

(4) DESCRIPTION OF THE INVENTION

(5) A schematic side view of a clamping assembly 1 according to the invention is shown in particular in FIG. 1. The clamping assembly 1 comprises an arrangement 2 of components 3, 4, 5, 6, 7 arranged above one another in a stack which have to be clamped together mechanically. In the exemplary embodiment of the invention illustrated in FIG. 1, the components 4 and 6 are semiconductor elements. The components 3, 5 and 7 are cooling plates that are manufactured of an electrically and thermally conductive material. Between the components 3-7 of the arrangement 2 there is thus a conductive connection, so that the components, and in particular the semiconductor modules 4, 6, constitute an electrical series circuit. The components 3-7 of the arrangement 2 are clamped together, in that a mechanical force generated by a clamping apparatus 30, is exercised on the arrangement 2 from both face sides. The clamping apparatus can, for example, be implemented in the form of a screw mechanism. The direction of the mechanical force generated by the clamping apparatus is indicated in FIG. 1 through the reference signs 8 and 9. The transmission of the mechanical force to the clamping assembly 1 is performed by means of a pressure element 10 and a pressure counter-element 11. In the exemplary embodiment of the clamping assembly 1 illustrated in FIG. 1, the clamping assembly 1 has a circular base area. For this reason, the pressure element 10 and the pressure counter-element 11 have the form of truncated cones.

(6) The pressure element 10 contains metal foam materials, wherein the metal foam materials form five partial regions 12-16. The partial regions 12, 13, 14, 15 and 16 are arranged in such a way that they partially enclose each other. Partial region 12 is here partially enclosed by partial region 13, partial region 13 and partial region 14 and, correspondingly, partial region 15, by partial region 16. A metal foam material is assigned to each partial region 12-16, wherein the metal foam materials differ from one another in particular in their moduli of elasticity.

(7) The metal foam material in partial region 12 here has the lowest modulus of elasticity. This corresponds to a highest gas content, i.e. a lowest stiffness, of all the partial regions. Accordingly, the modulus of elasticity of the metal foam materials rises in partial regions 13-16 from inside to outside with respect to a central or symmetrical axis 17 of the clamping assembly.

(8) The pressure counter-element 11 is arranged opposite the pressure element 10. The construction of the pressure counter-element 11 mirrors that of pressure element 10. The pressure counter element 11 thus comprises partial regions 18, 19, 20, 21, 22, to each of which a metal foam material is assigned. The partial regions 18-22 differ from one another in the metal foam materials that they contain. Each of the metal foam materials exhibits a modulus of elasticity which, corresponding to that of pressure element 10, exhibits a rising value from the inside to the outside with reference to the axis 17.

(9) An exemplary embodiment of a sub module 23 according to the invention is illustrated in FIG. 2. The sub module 23 is constructed as a two-terminal network, wherein the poles (the terminals) of the sub module 23 are identified in FIG. 2 with reference signs 24 and 25 respectively. The sub module 23 constitutes a part of a converter, not shown graphically in FIG. 2, wherein a plurality of further sub modules 23, with the same construction as that of sub module 23, are connected in series to form a converter phase branch. Sub module 23 comprises a series circuit of power semiconductor switching units 26, wherein each of the two power semiconductor switching units 26 consists of a power semiconductor switch 27 and a diode 28 connected in parallel with it but in the opposite sense. The sub module 23 further comprises a storage capacitor 29, which is arranged in parallel with the series circuit of the power semiconductor switching units 26. The series circuit of the power semiconductor switching units 26 is implemented in the form of a clamping assembly 1 illustrated in FIG. 1.

LIST OF REFERENCE SIGNS

(10) 1 Clamping assembly 2 Arrangement of components 3-7 Component 8, 9 Arrow 10 Pressure element 11 Pressure counter-element 12-16 Partial region 17 Central axis 18-22 Partial region 23 Sub module 24, 25 Terminal 26 Power semiconductor switching unit 27 Power semiconductor switch 28 Diode 29 Energy store