Housing for an electronic circuit

• US 7,508,682 B2
• Filed: 09/19/2005
• Issued: 03/24/2009
• Est. Priority Date: 09/19/2005
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Badarinarayan, Harsha, Okamoto, Kazutaka, Hunt, Frank
• Primary Examiner(s): Bui; Hung S
• Application Number:
  US11/230,099
• Publication Number:
  US 20070064403A1
• Time in Patent Office: 1,282 Days
• Field of Search: 361/790, 361/797, 361/800, 361/737, 361/727, 312/223
• US Class Current: 361/797
• CPC Class Codes: B23K 20/1265 Non-butt welded joints, e.g. overlap-joints, T-joints or spot welds
• CPC Class Codes: H05K 5/0052 characterized by joining features of the housing parts
• CPC Class Codes: H05K 5/066 sealed by fusion of the joining parts without bringing material; sealed by brazing

Abstract

A housing for an electrical circuit having a metal base with an open top and a metal lid which overlies the open top of the base and forms an interior chamber adapted to contain an electronic circuit. The outer periphery of the lid is attached to the base by friction stir welding to thereby form a hermetically sealed chamber dimensioned to contain an electronic circuit. An electronic port is electrically connected to the electronic circuit and accessible exteriorly of the housing.

Claims

1. A housing comprising:

a metal base having an open top and forming a chamber, an electronic circuit positioned in said chamber,

a metal lid overlying said open top of said base so that said electronic circuit is entirely contained in said chamber between said metal base and said metal lid and so that an outer periphery of said metal base flatly abuts against an outer periphery of said metal lid, said lid being attached to said base continuously around said outer periphery of said lid and said outer periphery of said base by a friction stir weld to thereby hermetically seal said chamber containing said electronic circuit,

an electrical port electrically connected to said electronic circuit and accessible exteriorly of the housing; and

wherein said base includes a support ledge around said open top of said base, said lid having an outer peripheral portion abutment with and supported by said ledge.

2. The invention as defined in claim 1 wherein said base includes a plurality of opposed sidewalls and comprising an intermediate wall extending between two sidewalls of said base, said lid abutting against and secured to said intermediate wall by friction stir welding.

3. The invention as defined in claim 1 and comprising a thermal isolator disposed between said base and the electronic circuit.

4. The invention as defined in claim 1 and comprising a separator wall sandwiched between said lid and said base and secured to said base and said lid by said friction stir weld.

5. The invention as defined in claim 1 wherein said base comprises a bottom and side walls extending outwardly from said bottom.

6. A method for constructing a housing comprising the steps of:

forming a metal base having an open top and defining a chamber,

placing an electronic circuit in said chamber,

forming a metal lid dimensioned to overlie and cover said open top of said base and said chamber and so that an outer periphery of said lid flatly abuts against an outer periphery of said housing,

friction stir welding said lid to said base continuously around said outer periphery of said lid and said outer periphery of said base, to thereby hermetically seal said electronic circuit in said chamber,

providing an electrical port electrically connected with the electronic circuit and accessible exteriorly of the housing; and

forming said base includes a support ledge around said open top of said, said lid having an outer peripheral portion abutment with and supported by said ledge.

7. The invention as defined in claim 6 wherein said base has at least one sidewall and a bottom and further comprising the step of cooling at least a portion of the sidewall during said welding step.

8. The invention as defined in claim 7 and further comprising the step of cooling at least a portion of the bottom during said welding step.

9. The invention as defined in claim 8 and wherein said step of cooling at least a portion of the bottom during said welding step further comprises the step of cooling the entire bottom during said welding step.

10. The invention as defined in claim 7 wherein said cooling step comprises the step of placing a chill having an internal fluid passageway in contact with the sidewall and flowing a coolant through the fluid passageway.

11. The invention as defined in claim 10 wherein said coolant comprises a liquid.

12. A housing comprising:

a metal base having an open top and an open bottom for an electronic circuit and forming a first chamber,

a first electronic circuit positioned in said chamber,

a metal lid overlying said open top of said base so that said electronic circuit is entirely contained in said first chamber between said metal base and said metal lid and so that an outer periphery of said metal base flatly abuts against an upper outer periphery of said metal lid, said lid being attached to said base by a friction stir weld continuously around said upper outer periphery of the lid to thereby form a hermetically sealed chamber containing said first electronic circuit,

a metal bottom overlying said open bottom of said base and forming a second chamber between said metal bottom and said metal base, a second electronic circuit positioned in said second chamber, said bottom having an outer periphery which flatly abuts against a lower outer periphery of said metal base around said bottom, said bottom being attached to said base by a friction stir weld continuously around said lower outer periphery to thereby hermetically seal said second electronic circuit in said second chamber,

an electrical port electrically connected to at least one of said first and second electronic circuit and accessible exteriorly of the housing.

13. The invention as defined in claim 12 wherein said base includes a support ledge around said open top of said base, said lid having an outer peripheral portion in abutment with and supported by said ledge.

14. The invention as defined in claim 13 wherein said base includes a plurality of opposed sidewalls and comprising an intermediate wall extending between two sidewalls of said base, said lid abutting against and secured to said intermediate wall by friction stir welding.

15. The invention as defined in claim 12 wherein said base includes a support ledge around said open bottom of said base, said bottom having an outer peripheral portion in abutment with and supported by said ledge.

16. The invention as defined in claim 12 wherein one of said electronic circuits comprises a circuit for an automotive vehicle.

17. The invention as defined in claim 16 wherein one of said circuits comprises an electronic control unit (ECU) for the vehicle.

18. The invention as defined in claim 12 and comprising a second electronic circuit contained in said second housing chamber.

19. The invention as defined in claim 18 wherein said second chamber is hermetically sealed.

20. The invention as defined in claim 12 and comprising a fluid coolant in said second housing chamber.