Phase change heat sink for use in electrical solenoids and motors

• US 7,069,979 B2
• Filed: 04/17/2002
• Issued: 07/04/2006
• Est. Priority Date: 05/02/2001
• Status: Expired due to Fees

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Tobias, Lee A.
• Primary Examiner(s): CIRIC, LJILJANA V
• Application Number:
  US10/123,418
• Publication Number:
  US 20020164277A1
• Time in Patent Office: 1,539 Days
• Field of Search: 165/104.23, 165/10, 165/905, 62/31, 62/32, 417/322, 417/438
• US Class Current: 165/104.33
• CPC Class Codes: H02K 9/20 wherein the cooling medium vaporises within the machine casing
• CPC Class Codes: H02K 9/22 by solid heat conducting material embedded in, or arranged in contact with, the stator or rotor, e.g. heat bridges

Abstract

A method, and a system for reducing the internal temperature of an electrical solenoid or motor device involves placing a heat absorbing phase change material (PCM) in intimate contact with the device to reduce the internal temperature of the device. The PCM material reduces the internal operational temperature of the device by undergoing an endothermic phase transition in an operating temperature range of the device. The PCM material transitions between a solid phase and a liquid phase in the internal operational temperature range of the device, or between a liquid phase and a gaseous phase in the internal operational temperature range of the device. The PCM material can be affixed externally to the device. For example, the PCM material is affixed in the form of externally placed pads to the device. The PCM material can also be affixed inside of the device. For example, the PCM material is placed in a potted position around and inside of coil windings of the device, or within an outer structure of the device.

Claims

1. A method for reducing the temperature of an electrical solenoid device, an electric motor device, or both, comprising:

placing a heat absorbing phase change material (PCM) in contact with the windings of said device, wherein the PCM material is contained within a housing that further contains said electric solenoid device or said electric motor device; and

,

wherein said housing is a flexible, bellows-resembling structure which can expand or contract in response to changes in the state of the PCM to reduce the temperature of the device.

2. A method according to claim 1, wherein said PCM material reduces the operational temperature of the device by undergoing an endothermic (heat absorbing) phase transition in a predetermined operating temperature range that is determined for said device.

3. A method according to claim 2, wherein said PCM material transitions between a solid phase and a liquid phase in said predetermined operational temperature range.

4. A method according to claim 2, wherein said PCM material transitions between a liquid phase and a gaseous phase.

5. A method according to claim 1, wherein additional PCM material is further affixed externally to a housing of the device in a contact relationship that permits heat transfer.

6. A method according to claim 5, wherein said PCM material is affixed in the form of externally placed pads to the electric solenoid or electric motor.

7. A system for reducing the temperature of an electrical solenoid device, an electric motor device, or both, comprising:

an outer housing structure that contains said electrical solenoid or electric motor device;

one or more internal components contained within said outer housing structure; and

phase change material (PCM) material contained in said housing and in contact with said device to reduce the temperature of the device,

wherein said housing structure is a flexible, bellows-resembling structure which can expand or contract in response to changes in the state of the PCM.

8. A system according to claim 7, wherein said PCM material is a material that reduces the operational temperature of the device by undergoing an endothermic phase transition in an operating temperature range of the device, said operating temperature range being predetermined.

9. A system according to claim 8, wherein said PCM material is a material that transitions between a solid phase and a liquid phase in said predetermined operating temperature range of the device.

10. A system according to claim 8, wherein said PCM material is a material that transitions between a liquid phase and a gaseous phase in said predetermined operating temperature range of the device.

11. A system according to claim 7, wherein said PCM material is further affixed externally to said housing of device.

12. A system according to claim 11, wherein said PCM material is affixed in the form of externally placed pads to the device.