Thermally conductive assemblies with wedge blocks for contact heat conduction suitable for electrical devices such as load centers

• US 10,292,310 B2
• Filed: 10/04/2017
• Issued: 05/14/2019
• Est. Priority Date: 12/22/2016
• Status: Active Grant

• Current Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Original Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Inventors: Maloney, James Gerard, Gehlbach, James Lee
• Primary Examiner(s): Smith, Courtney L
• Application Number:
  US15/724,349
• Publication Number:
  US 20180184544A1
• Time in Patent Office: 587 Days
• Field of Search: None
• CPC Class Codes: F28F 21/04 of ceramic; of concrete; of natural stone
• CPC Class Codes: F28F 21/084 from aluminium or aluminium alloys
• CPC Class Codes: F28F 21/085 from copper or copper alloys
• CPC Class Codes: H02B 1/056 Mounting on plugboards
• CPC Class Codes: H02B 1/06 having associated enclosures, e.g. for preventing access to live parts
• CPC Class Codes: H02B 1/21 Bus-bar arrangements for rack-mounted devices with withdrawable units
• CPC Class Codes: H02B 1/56 Cooling; Ventilation
• CPC Class Codes: H02G 3/14 Fastening of cover or lid to box
• CPC Class Codes: H05K 2201/10272 Busbars, i.e. thick metal bars mounted on the printed circuit board [PCB] as high-current conductors
• CPC Class Codes: H05K 7/2039 characterised by the heat transfer by conduction from the heat generating element to a dissipating body arrangements for increasing/decreasing heat-transfer, e.g. fins details, F28F13/00

Abstract

Thermally conductive assemblies that provide a heat conduction path include at least one thermally conductive wedge block that can be held in a receptacle with a wall having sufficient flexibility to be able to expand outward in response to an outward force applied by the at least one thermally conductive wedge block. The wedge block can also be electrically resistive.

Claims

1. A thermally conductive assembly comprising:

at least one first wedge block, wherein the at least one first wedge block is thermally conductive and has an outer surface with an inclined plane;

a housing having at least one receptacle defining an open channel that holds the at least one first wedge block with the inclined plane residing external to the housing; and

at least one second wedge block, each of the at least one second wedge block comprising a respective inclined plane that faces the inclined plane of an aligned one of the at least one first wedge block, wherein, at 20 degrees Celsius, the at least one first wedge block conducts electricity at a value that is less than 50% that of the at least one second wedge block.

2. The assembly of claim 1, wherein the at least one first wedge block is a plurality of first wedge blocks, each having a respective inclined plane with an angle of inclination in a range of about 35-75 degrees, and wherein, measured at 20 degrees Celsius, the at least one first wedge block has a thermal conductivity in a range of about 50 W/m-K* to about 205 W/m-K*.

3. The assembly of claim 1, wherein the housing is electrically resistive, and wherein the at least one receptacle has a wall that is sufficiently flexible to be able to expand outward in response to an outward force applied by the at least one first wedge block.

4. The assembly of claim 1, wherein the at least one first wedge block is a plurality of spaced apart first wedge blocks, and wherein the plurality of first wedge blocks have an electrical resistivity ρ

(Ω

·

m) at 20 degrees Celsius of at least about 1×

10³ or about 1-100×

10¹³ or greater.

6. The assembly of claim 1, wherein the at least one first wedge block comprises boron nitride.

7. The assembly of claim 1, wherein the at least one receptacle is a plurality of spaced apart receptacles that are vertically or horizontally aligned, and wherein the at least one first wedge block is a plurality of first wedge blocks with a planar bottom surface that opposes an outer surface thereof with the inclined plane, with one first wedge block in a corresponding one of the receptacles.

5. A thermally conductive assembly comprising:

at least one first wedge block, wherein the at least one first wedge block is thermally conductive and has an outer surface with an inclined plane; and

a housing having at least one receptacle that holds the at least one first wedge block with the inclined plane residing external to the housing,

wherein the housing is rectangular, wherein the at least one receptacle is a plurality of spaced apart but adjacent receptacles, wherein the at least one first wedge block is a plurality of first wedge blocks, one in each of the receptacles, and wherein the first wedge blocks cooperate with the housing and, in use, each first wedge block can slidably move in a respective receptacle upon contact with a matable second wedge block.

8. A thermally conductive assembly comprising:

at least one first wedge block, wherein the at least one first wedge block is thermally conductive and has an outer surface with an inclined plane;

a housing having at least one receptacle that holds the at least one first wedge block with the inclined plane residing external to the housing; and

at least one second wedge block comprising a respective inclined plane that faces the inclined plane of an aligned one of the at least one first wedge block,

wherein the at least one second wedge block is electrically conductive and thermally conductive, and wherein the at least one second wedge block comprises a planar extension that projects outwardly a distance from the inclined plane of the second wedge block and comprises an aperture configured to receive a fixation member.

9. A thermally conductive assembly comprising:

at least one first wedge block, wherein the at least one first wedge block is thermally conductive and has an outer surface with an inclined plane;

a housing having at least one receptacle that holds the at least one first wedge block with the inclined plane residing external to the housing; and

at least one second wedge block comprising a respective inclined plane that faces the inclined plane of an aligned one of the at least one first wedge block,

wherein the at least one second wedge block comprises copper or aluminum, and wherein the at least one first wedge block comprises boron nitride.

10. A load center comprising:

an enclosure having an interior compartment;

a heat sink member in the interior compartment;

one or more bus bars attached to one or more bus terminals in the interior compartment;

a circuit breaker in the interior compartment electrically engaged with the one or more bus bars;

at least one first wedge block in the interior compartment thermally coupled to the heat sink member, wherein the at least one first wedge block is thermally conductive; and

at least one second wedge block thermally coupled to the one or more bus bars and cooperatively engaged with the at least one first wedge block,

wherein the at least one first wedge block and the at least one second wedge block each comprise an inclined plane, and wherein the inclined planes of pairs of the at least one first and second wedge blocks face each other.

12. The load center of claim 10, wherein the at least one first wedge block is a plurality of first wedge blocks, the load center further comprising a wedge block housing that comprises a plurality of spaced apart receptacles holding respective first wedge blocks of the plurality of first wedge blocks.

13. The load center of claim 10, wherein the at least one second wedge block is attached to the one or more bus terminals, wherein the at least one second wedge block comprises copper or aluminum, and wherein the at least one first wedge block comprises boron nitride.

14. The load center of claim 10, wherein the at least one first wedge block is a plurality of first wedge blocks, each having an inclined plane having an angle of inclination in a range of 35-75 degrees, and wherein the plurality of the first wedge blocks are electrically resistive.

15. The load center of claim 10, wherein the at least one first wedge block comprises boron nitride.

11. A load center comprising:

an enclosure having an interior compartment;

a heat sink member in the interior compartment;

one or more bus bars attached to one or more bus terminals in the interior compartment;

a circuit breaker in the interior compartment electrically engaged with the one or more bus bars;

at least one first wedge block in the interior compartment thermally coupled to the heat sink member, wherein the at least one first wedge block is thermally conductive; and

at least one second wedge block thermally coupled to the one or more bus bars and cooperatively engaged with the at least one first wedge block,

wherein the at least one first wedge block is held in a wedge block housing that has at least one receptacle with a wall that is sufficiently flexible to be able to expand in response to sliding movement of the at least one first wedge block relative to the second wedge block as the circuit breaker is tightened into position.

16. A load center comprising:

an enclosure having an interior compartment;

a heat sink member in the interior compartment;

one or more bus bars attached to one or more bus terminals in the interior compartment;

a circuit breaker in the interior compartment electrically engaged with the one or more bus bars;

at least one first wedge block in the interior compartment thermally coupled to the heat sink member, wherein the at least one first wedge block is thermally conductive; and

at least one second wedge block thermally coupled to the one or more bus bars and cooperatively engaged with the at least one first wedge block,

wherein the at least one second wedge block is electrically conductive and thermally conductive, and wherein the at least one second wedge block comprises a planar extension that projects outwardly a distance from a body portion with an inclined plane, wherein the planar extension comprises an aperture, and wherein the load center further comprises a fixation member extending through the aperture and attached to a respective one of the one or more bus terminals.

17. A method of installing a heat conduction device to an electrical device, comprising:

providing at least one first wedge block, wherein the at least one first wedge block is thermally conductive, and wherein the at least one wedge block is held in an electrically resistive housing having a receptacle with a wall that is flexible to be able to expand laterally;

providing at least one second wedge block, wherein the at least one second wedge block is thermally conductive and electrically conductive;

slidably engaging at least one pair of the at least one first and the at least one second wedge blocks with inclined planes of each pair facing each other; and

providing a heat conduction path between the at least one pair of the at least one first and second wedge blocks.

19. The method of claim 17, wherein the at least one first wedge block comprises boron nitride and the at least one second wedge block comprises copper or aluminum.

18. A method of installing a heat conduction device to an electrical device, comprising:

providing at least one first wedge block, wherein the at least one first wedge block is thermally conductive, and wherein the at least one wedge block is held in an electrically resistive housing having a receptacle with a wall that is flexible to be able to expand laterally;

providing at least one second wedge block, wherein the at least one second wedge block is thermally conductive and electrically conductive;

slidably engaging at least one pair of the at least one first and the at least one second wedge blocks with inclined planes of each pair facing each other; and

providing a heat conduction path between the at least one pair of the at least one first and second wedge blocks,

wherein the at least one first wedge block and the at least one second wedge block are each pluralities, and wherein the at least one pair comprises first, second and third pairs of the first and second wedge blocks, the method further comprising;

tightening a connection to a circuit breaker using a fixation member extending through the at least one second wedge block;

creating an interference fit between the pairs of wedge blocks in response to the tightening; and

sliding the first wedge block of the pairs of first and second wedge blocks based on the created interference fit while maintaining positive contact between the first, second and third pairs of first and second wedge blocks to provide the heat conduction path,

wherein the first wedge blocks comprise boron nitride and the second wedge blocks comprise copper or aluminum, and wherein the pairs are held in a load center and the heat conduction path is between bus bar terminals and a heat sink member of a back pan and/or metal panel through the first, second and third pairs of the first and second wedge blocks.