Orientation independent evaporator

• US 5,761,037 A
• Filed: 02/12/1996
• Issued: 06/02/1998
• Est. Priority Date: 02/12/1996
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Chrysler, Gregory Martin, Anderson, Timothy Merrill, Chu, Richard Chao-Fan
• Primary Examiner(s): Tolin, Gerald P.
• Application Number:
  US08/598,593
• Time in Patent Office: 841 Days
• Field of Search: 165/80.3, 165/185, 165/80.4, 165/104.21, 165/104.14, 165/104.26, 165/104.23, 62/225, 62/515, 62/516, 62/259.2, 174/15.2, 257/714, 361/690, 361/698, 361/699, 361/700, 361/717-719
• US Class Current: 361/700
• CPC Class Codes: F28D 15/0266 with separate evaporating and condensing chambers connected by at least one conduit; Loop-type heat pipes; with multiple or common evaporating or condensing chambers F28D15/043 takes precedence
• CPC Class Codes: F28D 15/04 with tubes having a capillary structure
• CPC Class Codes: H01L 2224/16 of an individual bump connector
• CPC Class Codes: H01L 23/427 Cooling by change of state, e.g. use of heat pipes by liquefied gas H01L23/445

Abstract

In accordance with a preferred embodiment of the present invention, an orientation independent evaporator includes a wicking member which also operates as a manifold which possesses a number of surface accessible channels preferably via grooves cut in either side of a slab of wicking material at right angles to one another. The evaporator is, because of the structure of this wicking member, able to be operated in any orientation with respect to a gravitational field. The invention provides an improved evaporator for use in thermosyphons, and in particular, provides an improved mechanism for cooling electronic components.

Claims

1. An orientation independent evaporator for cooling a body, said evaporator comprising:

a housing for containing an evaporatable cooling fluid, said housing having an extended surface for thermal contact with said body which is to be cooled, said extended surface having at least a portion thereof exposed to interior portions of said housing which also includes an inlet port;

a wicking layer in thermal contact with said extended surface and disposed within the interior of said housing; and

a wicking member in contact with said wicking layer, said wicking member also being disposed in said housing, said wicking member having a plurality of surface accessible channels, said channels being regularly shaped and sufficiently wide for the passage of liquid phase cooling fluid therethrough without capillary action, said channels not being pores, and which also permit passage of cooling fluid vapor generated at said wicking layer through said wicking member to an exhaust port in said housing.

2. The evaporator of claim 1 in which said wicking member channels comprise grooves on one side extending in a first direction and grooves on an opposite side thereof extending in a direction at an angle to said first direction, said grooves on each side being in fluid communication with said grooves on said opposite side.

3. Evaporator of claim 2 in which said first and second directions are at right angles to one another.

4. Evaporator of claim 1 in which said wicking layer comprises a material selected from the group consisting of sintered copper, aluminum foam, silicon carbide, vitreous carbon, copper mesh and copper screen.

5. Evaporator of claim 1 in which said wicking member comprises a material selected from the group consisting of sintered copper, aluminum foam, silicon carbide, vitreous carbon, copper mesh and copper screen.

6. The evaporator of claim 1 further including a spreader wick disposed against said wicking member on the opposite side thereof from said wicking layer.

7. A thermosyphon system comprising:

a housing for containing an evaporatable cooling fluid, said housing having an extended surface for thermal contact with said body which is to be cooled, said extended surface having at least a portion thereof exposed to interior portions of said housing which also includes an inlet port;

a wicking layer in thermal contact with said extended surface and disposed within the interior of said housing; and

a wicking member in contact with said wicking layer, said wicking member also being disposed in said housing, said wicking member having a plurality of surface accessible channels, said channels being regularly shaped and sufficiently wide for the passage of liquid phase cooling fluid therethrough without capillary action, said channels not being pores, and which also permit passage of cooling fluid vapor generated at said wicking layer through said wicking member to an exhaust port in said housing;

a condenser;

flow communication means connecting said exhaust port to an inlet of said condenser; and

flow communication means connecting an outlet of said condenser to said inlet port.

8. The thermosyphon of claim 7 wherein said wicking member comprises material selected from the group consisting of sintered copper, aluminum foam, silicon carbide, vitreous carbon, copper mesh and copper screen.

9. The system of claim 7 wherein said system includes a coolant fluid selected from the group consisting of water, refrigerant and fluorocarbon.

10. A system cooled by thermosyphon means comprising:

a housing for containing an evaporatable cooling fluid, said housing having an extended surface for thermal contact with said body which is to be cooled, said extended surface having at least a portion thereof exposed to interior portions of said housing which also includes an inlet port;

a wicking layer in thermal contact with said extended surface and disposed within the interior of said housing; and

a wicking member in contact with said wicking layer, said wicking member also being disposed in said housing, said wicking member having a plurality of surface accessible channels, said channels being regularly shaped and sufficiently wide for the passage of liquid phase cooling fluid therethrough without capillary action, said channels not being pores, and which also permit passage of cooling fluid vapor generated at said wicking layer through said wicking member to an exhaust port in said housing;

a condenser;

flow communication means connecting said exhaust port to an inlet of said condenser;

flow communication means connecting an outlet of said condenser to said inlet port; and

an electronic package heat source in thermal contact with said extended surface of said housing.

11. The system of claim 10 wherein said system includes a coolant fluid selected from the group consisting of water, refrigerant and fluorocarbon.

12. The system of claim 10 wherein said wicking layer comprises material selected from the group consisting of sintered copper, aluminum foam, silicon carbide, vitreous carbon, copper mesh and copper screen.