Electronic component module assembly and method for assembling electronic component module assembly

Abstract

To provide a cooling mechanism for an electronic component mounted on a printed wiring board.SOLUTION: An electronic component module assembly includes a printed wiring board, and a stiffener assembly affixed to a first side of the printed wiring board. The stiffener assembly includes an outer stiffener secured to the printed wiring board, and an inner stiffener removably located in an opening of the outer stiffener. The inner stiffener has one or more inner stiffener pockets formed therein, and one or more electronic components are installed in one or more inner stiffener pockets, and electrically connected to the printed wiring board.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to the art of electrical power systems, and in particular to the assembly, disassembly and cooling of such systems. [Background technology]

[0002] A power system, for example, may comprise one or more half-bridge modules secured to a printed wiring board (PWB). A half-bridge module is a package of silicon carbide field effect transistors (SiCFETs) and diodes. Thermal management of half-bridge modules presents unique challenges. One of the two large faces of the half-bridge module is secured to the PWB to establish an electrical connection. However, heat dissipation from the half-bridge module occurs through the face opposite the face in contact with the PWB. Heat dissipation in such a structure occurs through the faces of the four half-bridge modules that are opposite the face of the half-bridge module that is secured against the PWB. Summary of the Invention [Problem to be solved by the invention]

[0003] As such power systems, such as those for space applications, become increasingly power dense, solutions are needed to adequately cool the components of the power system. Additionally, it is desirable to improve the modularity of such systems, thereby making them easier to assemble and easier to disassemble or replace components. [Means for solving the problem]

[0004] In one embodiment, an electronic component module assembly includes a printed wiring board and a stiffener assembly attached to a first side of the printed wiring board. The stiffener assembly includes an outer stiffener secured to the printed wiring board and an inner stiffener removably disposed in an opening in the outer stiffener. The inner stiffener has one or more inner stiffener pockets formed therein, and one or more electronic components are mounted in the one or more inner stiffener pockets and electrically connected to the printed wiring board.

[0005] Additionally or alternatively, in this or other embodiments, the inner stiffener includes a tapered inner stiffener end and the outer stiffener includes a complementary tapered inner stiffener end, the tapered inner stiffener end and the tapered outer stiffener end defining a guide for placement and attachment of the inner stiffener to the outer stiffener.

[0006] Additionally or alternatively, in this or other embodiments, the inner and outer stiffeners are formed from an aluminum material.

[0007] Additionally or alternatively, in this or other embodiments, one or more wedge lock rails are disposed on the outer stiffener and the inner stiffener, and a wedge lock is disposed on each wedge lock rail of the one or more wedge lock rails to secure the inner stiffener to the outer stiffener.

[0008] Additionally or alternatively, in this or other embodiments, a first cover is secured to the stiffener assembly on a side of the stiffener opposite the printed wiring board.

[0009] Additionally or alternatively, in this or other embodiments, a second cover is secured to the printed wiring board on a side of the printed wiring board opposite the stiffener assembly.

[0010] Additionally or alternatively, in this or other embodiments, the first cover and the second cover are formed from an aluminum material.

[0011] Additionally or alternatively, in this or other embodiments, the top cover is in thermal contact with one or more stiffener ribs of the stiffener assembly.

[0012] Additionally or alternatively, in this or other embodiments, the outer stiffener is secured to the printed wiring board by an adhesive.

[0013] Additionally or alternatively, in this or other embodiments, the printed wiring board is secured to the outer stiffener on a first side of the outer stiffener and the inner stiffener is attached to a second side of the outer stiffener opposite the first side of the outer stiffener.

[0014] Additionally or alternatively, in this or other embodiments, the one or more electronic components include one or more of a half-bridge module, a MOSFET, a diode, or a transistor.

[0015] In another embodiment, a method of assembling an electronic component module assembly includes attaching one or more electronic components to a first inner stiffener side of an inner stiffener and attaching the inner stiffener to an opening defined in an outer stiffener, the inner stiffener being attached to the first outer stiffener side of the outer stiffener. A printed wiring board is secured to a second outer stiffener side of the outer stiffener opposite the first outer stiffener side. The securing places the one or more electronic components in electrical contact with the printed wiring board.

[0016] Additionally or alternatively, in this or other embodiments, the inner stiffener includes a tapered inner stiffener end and the outer stiffener includes a complementary tapered inner stiffener end, the tapered inner stiffener end and the tapered outer stiffener end defining a guide for placement and attachment of the inner stiffener to the outer stiffener.

[0017] Additionally or alternatively, in this or other embodiments, the wedge locks are attached to one or more wedge lock rails disposed on the outer stiffener and the inner stiffener, thereby securing the inner stiffener to the outer stiffener.

[0018] Additionally or alternatively, in this or other embodiments, the first cover is secured to the inner stiffener on a second inner stiffener side of the inner stiffener opposite the first inner stiffener side.

[0019] Additionally or alternatively, in this or other embodiments, a second cover is secured to the printed wiring board on a side of the printed wiring board opposite the outer stiffener.

[0020] Additionally or alternatively, in this or other embodiments, the top cover is in thermal contact with one or more stiffener ribs of the inner stiffener.

[0021] Additionally or alternatively, in this or other embodiments, the outer stiffener is secured to the printed wiring board by an adhesive.

[0022] Additionally or alternatively, in this or other embodiments, the one or more electronic components include one or more of a half-bridge module, a MOSFET, a diode, or a transistor.

[0023] Additionally or alternatively, in this or other embodiments, the inner and outer stiffeners are formed from an aluminum material.

[0024] The following description should not be taken as limiting in any way.With reference to the accompanying drawings, like elements are numbered likewise. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1 is a perspective view of an embodiment of an electronics assembly module. [Diagram 2]1A and 1B are diagrams of an embodiment of a stiffener assembly of an assembled module. [Diagram 3] FIG. 13 is another view of an embodiment of a stiffener assembly of the assembled module. [Figure 4] 1A-1D are diagrams of an assembly process for an embodiment of a stiffener assembly. [Diagram 5] 1A-1D are diagrams of an assembly process for an embodiment of an assembled module. [Figure 6] FIG. 13 is a diagram of thermal energy transfer in an embodiment of an assembled module. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] A detailed description of one or more embodiments of the disclosed apparatus and methods is presented herein, by way of example and not limitation, with reference to the drawings.

[0027] 1, there is shown a perspective view of an electronics assembly module 10. The assembly module 10 includes a printed wiring board (PWB) 12, a stiffener assembly 14 secured to the PWB 12, a first cover 16 disposed over the stiffener assembly 14 on a first side 18 of the PWB 12, and a second cover 20 disposed on a second side 22 of the PWB 12 opposite the first side 18. Wedgelocks 24 or other fastening mechanisms are utilized to secure the assembled module 10 within an electronics box.

[0028] 2 and 3, a partially exploded view of the assembled module 10 is shown. FIG. 2 shows the stiffener assembly 14 mounted to the PWB 12. The stiffener assembly 14 includes an outer stiffener 26 and an inner stiffener 28 mounted within the outer stiffener 26. The outer stiffener 26 and the inner stiffener 28 are formed from a highly thermally conductive material, such as aluminum or an aluminum alloy. As shown, the inner stiffener 28 is disposed inside the outer stiffener 26 in the longitudinal direction 30 of the stiffener assembly 14. The stiffener assembly 14 includes a bottom surface 32 and a top surface 34 opposite the bottom surface 32, and the outer stiffener portion 36 of the bottom surface 32 is bonded to the PWB 12, for example, by an adhesive between the outer stiffener portion 36 and the PWB 12. The inner stiffener 28 is not in adhesive contact with the PWB 12 and is easily removable from the outer stiffener 26 and the PWB 12. The inner stiffener 28 is secured to the outer stiffener 26 via wedgelocks 24. The inner stiffener 28 and outer stiffener 26 include a longitudinally extending wedgelock rail 38 to which the wedgelocks 24 are attached.

[0029] 3, a view of the stiffener assembly 14 is shown removed from the PWB 12 with the first cover 16 attached to the top surface 34 of the stiffener assembly 14. As shown in FIG. 3, the stiffener assembly 14 includes a plurality of inner stiffener ribs 40 on the inner stiffener 28 defining a plurality of inner stiffener pockets 42 therebetween. Similarly, the outer stiffener 26 includes a plurality of outer stiffener ribs 44 defining a plurality of outer stiffener pockets 46 therebetween. The inner stiffener 28 may include a center rail 48 that extends across the inner stiffener 28 in a width direction 50 perpendicular to the length direction. In some embodiments, the inner stiffener 28 is symmetrical about the center rail 48. Additionally, in some embodiments, the center rail 48 has a larger cross-sectional area than the inner stiffener ribs 40.

[0030] When the assembled module 10 is completed, one or more electronic components are mounted in the plurality of inner stiffener pockets 42 such that the one or more electronic components are electrically connected to the PWB 12. For example, in the embodiment of FIG. 3 , the electronic components are four half-bridge modules 52. Each of the half-bridge modules 52 is secured to the inner stiffener pocket 42, for example, with one or more screws or other fasteners. Although four half-bridge modules 52 are shown mounted in the inner stiffener pocket 42, one skilled in the art of printed wiring board design will readily appreciate that additional electronic components and / or components other than the half-bridge assemblies 52 may be mounted in the inner stiffener pocket 42. Examples of such other electronic components include MOSFETs, diodes, transistors, etc.

[0031] The assembled module 10 is configured to facilitate assembly of the half-bridge modules 52 to the assembled module 10 and to facilitate replacement of the half-bridge modules 52 by installation and removal of the inner stiffeners 28. To assemble the assembled module 10, and with reference to FIG. 4, the half-bridge modules 52 are attached to the bottom surface 54 of the inner stiffener. The inner stiffener 28 is then attached to the outer stiffener 26. The inner stiffener 28 includes a tapered inner stiffener end 56, and the outer stiffener 26 includes a complementary tapered outer stiffener end 58. The tapered outer stiffener end 58 defines an opening 62 through which the inner stiffener 28 is attached, and the tapered outer stiffener end 58 and the tapered inner stiffener end 56 function as guides for aligning and attaching the inner stiffener 28 to the outer stiffener 26.

[0032] 5, after the inner stiffener 28 is attached to the outer stiffener 26 to form the stiffener assembly 14, the stiffener assembly 14 is attached to the PWB 12 and the outer stiffener 26 is secured to the PWB 12 by an adhesive to define a bonded, inseparable joint between the PWB 12 and the outer stiffener 26. Each half-bridge module 52 is electrically connected to the PWB 12 via a number of fasteners. The first cover 16 and the second cover 20 are then attached to the stiffener assembly 14 and the PWB 12. The wedgelocks 24 are attached to the wedgelock rails 38 to complete the assembled module 10.

[0033] 6, a cross-sectional view of the assembled module 10 is shown illustrating conductive heat transfer within the assembled module 10 for dissipating thermal energy from the half bridge modules 52. The half bridge modules 52 generate heat during operation, and the heat is conducted upward from the half bridge modules 52 into the inner stiffener 28. From the half bridge modules 52, the thermal energy is conducted, for example, through the inner stiffener rib 40 into the inner stiffener 28 and the outer stiffener 26, and through the outer stiffener rib 44 into the outer stiffener 26. The thermal energy is conducted toward and into the wedge lock rail 38, where it is removed from the assembled module 10 by a heat removal device 60, such as, for example, a cold plate or fan. Additionally, a small portion of the thermal energy from the half bridge modules is conducted through the first cover 16 toward the wedge lock rail 38 for additional heat removal capability from the half bridge modules 52.

[0034] The assembled module 10 and stiffener assemblies 14 described herein provide a unique thermal management solution for the half-bridge modules 52. Additionally, this structure improves the ease of assembly and disassembly of the half-bridge modules 52 within the assembled module 10, thus improving the ease of repair and / or replacement of the half-bridge modules 52. Additionally, the assembled module 10 may be utilized in a myriad of applications, such as deep space, ground-based, or underwater-based applications.

[0035] The term "about" is intended to include the degree of error associated with measurement of the particular quantity based on the equipment available at the time of filing.

[0036] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the present disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms unless the context clearly indicates otherwise. It will be further understood that the terms "comprise" and / or "comprising", as used herein, specify the presence of stated features, integers, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0037] Although the present disclosure has been described with reference to one or more exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for the elements thereof without departing from the scope of the present disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from the essential scope of the present disclosure. Therefore, it is not intended that the present disclosure be limited to the particular embodiment disclosed as the best mode contemplated for carrying out the disclosure, but rather, the present disclosure is intended to include all embodiments falling within the scope of the appended claims.

Claims

1. A printed wiring board; a stiffener assembly attached to a first side of the printed wiring board; 1. An electronic component module assembly comprising: an outer stiffener fixed to the printed wiring board; an inner stiffener removably disposed in the opening of the outer stiffener, the inner stiffener forming one or more inner stiffener pockets therein; one or more electronic components mounted in one or more inner stiffener pockets and electrically connected to the printed wiring board; Equipped with the inner stiffener comprises a tapered inner stiffener end; and the outer stiffener includes complementary tapered outer stiffener ends, the tapered inner stiffener end and the tapered outer stiffener end defining a guide for placement and attachment of the inner stiffener to the outer stiffener; one or more wedge lock rails disposed on the outer and inner stiffeners; a wedge lock disposed in each wedge lock rail of the one or more wedge lock rails to secure the inner stiffener to the outer stiffener; The electronic component module assembly further comprises:

2. The electronic component module assembly of claim 1 , wherein the inner and outer stiffeners are formed from an aluminum material.

3. 10. The electronic component module assembly of claim 1, further comprising a first cover secured to the stiffener assembly on a side of the stiffener assembly opposite the printed wiring board.

4. 4. The electronic component module assembly of claim 3, further comprising a second cover secured to the printed wiring board on a side of the printed wiring board opposite the stiffener assembly.

5. The electronic component module assembly of claim 4 , wherein the first cover and the second cover are formed from an aluminum material.

6. The electronic component module assembly of claim 3 , wherein the first cover is in thermal contact with one or more stiffener ribs of the stiffener assembly.

7. The electronic component module assembly of claim 1 , wherein the outer stiffener is secured to the printed wiring board by an adhesive.

8. 10. The electronic component module assembly of claim 1 , wherein the printed wiring board is secured to the outer stiffener on a first side of the outer stiffener and the inner stiffener is attached to a second side of the outer stiffener opposite the first side of the outer stiffener.

9. The electronic component module assembly of claim 1 , wherein the one or more electronic components include one or more of a half-bridge module, a MOSFET, a diode, or a transistor.

10. attaching one or more electronic components to a first inner stiffener side of the inner stiffener; attaching the inner stiffener to an opening defined in an outer stiffener, the inner stiffener being attached to a first outer stiffener side of the outer stiffener; fastening a printed wiring board to a second outer stiffener side of the outer stiffener opposite the first outer stiffener side, said fastening placing said one or more electronic components in electrical contact with said printed wiring board; Equipped with the inner stiffener comprises a tapered inner stiffener end; and the outer stiffener includes complementary tapered outer stiffener ends, the tapered inner stiffener end and the tapered outer stiffener end defining a guide for placement and attachment of the inner stiffener to the outer stiffener; 13. The method of assembling an electronic component module assembly, further comprising attaching wedgelocks to one or more wedgelock rails disposed on the outer stiffener and the inner stiffener, thereby securing the inner stiffener to the outer stiffener.

11. 11. The method of claim 10, further comprising securing a first cover to the inner stiffener on a second inner stiffener side of the inner stiffener opposite the first inner stiffener side.

12. The method of claim 11 , further comprising securing a second cover to the printed wiring board on a side of the printed wiring board opposite the outer stiffener.

13. The method of claim 11 , wherein the first cover is in thermal contact with one or more stiffener ribs of the inner stiffener.

14. The method of claim 10 , wherein the outer stiffener is secured to the printed wiring board by an adhesive.

15. The method of claim 10 , wherein the one or more electronic components include one or more of a half-bridge module, a MOSFET, a diode, or a transistor.

16. The method of claim 10 , wherein the inner and outer stiffeners are formed from an aluminum material.

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