Thermally conductive covers for electric circuit assemblies

• US 7,778,033 B2
• Filed: 10/30/2008
• Issued: 08/17/2010
• Est. Priority Date: 10/30/2008
• Status: Active Grant

• Current Assignee: Astec International Limited (Emerson Electric Company)
• Original Assignee: Astec International Limited (Emerson Electric Company)
• Inventors: Kretman, Matthew D.
• Primary Examiner(s): Thompson; Gregory D
• Application Number:
  US12/261,803
• Publication Number:
  US 20100110640A1
• Time in Patent Office: 656 Days
• Field of Search: 361/703, 361/715
• US Class Current: 361/703
• CPC Class Codes: H05K 7/209 Heat transfer by conduction from internal heat source to heat radiating structure H05K7/20909 takes precedence

Abstract

A method of producing a thermally conductive cover for an electric circuit assembly having a plurality of heat dissipating components is disclosed. The thermally conductive cover including a top surface, a bottom surface, and at least one rib extending downwardly from the bottom surface. The method includes selecting a plurality of dimensions for the thermally conductive cover such that the bottom surface will be spaced above and extend over top sides of the plurality of heat dissipating components when the thermally conductive cover is installed over the electronic circuit assembly. The at least one rib will extend over and be spaced from the plurality of heat dissipating components when the thermally conductive cover is installed over the electronic circuit assembly. The method further includes producing the thermally conductive cover with the selected dimensions. Thermally conductive covers are also disclosed.

Claims

1. An electronic circuit assembly comprising:

a plurality of heat dissipating components, each component having a top side; and

a thermally conductive cover having a top surface, a bottom surface, and at least one rib extending downwardly from the bottom surface, the bottom surface spaced above and extending over the top sides of the plurality of heat dissipating components, the at least one rib extending over and thermally coupled to the top side of at least one of the plurality of heat dissipating components for conductive transfer of heat from said at least one of the plurality of heat dissipating components to the at least one rib .

2. The assembly of claim 1 further comprising a circuit board supporting the plurality of heat dissipating components.

3. The assembly of claim 2 wherein the at least one rib is spaced from the circuit board.

4. The assembly of claim 2 wherein the circuit board has a top side and the bottom surface of the thermally conductive cover extends over an entirety of the circuit board'"'"'s top side.

5. The assembly of claim 4 wherein the circuit board includes a plurality of side edges, the thermally conductive cover includes a plurality of sides extending downwardly from the top surface, and the plurality of sides extend around and cover the plurality of side edges.

6. The assembly of claim 2 wherein the electronic circuit assembly is a power supply module configured to produce an output current or voltage from an input current or voltage.

7. The assembly of claim 6 wherein the plurality of heat dissipating components include an inductor, a transistor, and a controller for the transistor.

8. The assembly of claim 2 wherein the rib includes at least a first portion extending above and thermally coupled to the top side of a first one of the plurality of heat dissipating components and a second portion extending above and thermally coupled to the top side of a second one of the plurality of heat dissipating components.

9. The assembly of claim 2 wherein the thermally conductive cover is made of a polymer resin.

10. The assembly of claim 9 wherein the polymer resin includes a thermally conductive filler.

11. The case of claim 9 wherein the polymer resin is polyplenylene sulfide.

12. The assembly of claim 1 wherein the top surface of the thermally conductive cover is substantially planar.

13. The assembly of claim 1 wherein the at least one rib directly contacts the top side of said at least one of the plurality of heat dissipating components.

14. The assembly of claim 1 further comprising a thermally conductive material positioned between and contacting the at least one rib and the top side of said at least one of the plurality of heat dissipating components.

15. The assembly of claim 2 wherein the thermally conductive cover is mounted to the circuit board.

16. A method of producing a thermally conductive cover for an electric circuit assembly having a plurality of heat dissipating components, the thermally conductive cover including a top surface, a bottom surface, and at least one rib extending downwardly from the bottom surface, the method comprising:

selecting a plurality of dimensions for the thermally conductive cover such that the bottom surface will be spaced above and extend over top sides of the plurality of heat dissipating components and the at least one rib will extend over and be thermally coupled with a top side of at least one of the plurality of heat dissipating components when the thermally conductive cover is installed over the electronic circuit assembly to conductively transfer heat from said at least one of the plurality of heat dissipating components to the at least one rib; and

producing the thermally conductive cover with the selected dimensions.

17. The method of claim 16 wherein the thermally conductive cover is made of a polymer resin.

18. The method of claim 17 wherein producing the thermally conductive cover includes producing the thermally conductive cover by injection molding.

19. The method of claim 17 wherein the polymer resin includes a thermally conductive filler.

20. In a method of using a power supply module including producing a first maximum output current, the first maximum output current being thermally limited due to one or more heat dissipating components in the power supply module, the improvement comprising:

installing a thermally conductive cover over the power supply module, the thermally conductive cover including a bottom surface extending over and thermally coupled to top sides of the one or more heat dissipating components for conductive transfer of heat from the one or more heat dissipating components to the thermally conductive cover; and

producing a second maximum output current that is greater than the first maximum output current with the thermally conductive cover installed over the power supply module.

21. The method of claim 20 wherein the first maximum output current is about 10 amperes and the second maximum output current is about 20 amperes.

22. The method of claim 20 wherein the thermally conductive cover includes at least one rib extending downwardly from the bottom surface, and over the one or more heat dissipating components, the at least one rib thermally coupled to said one or more heat dissipating components to conductively transfer heat from said one or more heat dissipating components to the at least one rib.

23. The method of claim 22 wherein the thermally conductive cover is made of a polymer resin including a thermally conductive filler.

24. The method of claim 22 wherein the at least one rib includes at least a first portion extending above and thermally coupled to a first heat dissipating component of the one or more heat dissipating components and a second portion extending above and thermally coupled to a second heat dissipating component of the one or more heat dissipating components.