Fluidic pump for heat management

• US 7,398,818 B2
• Filed: 12/27/2005
• Issued: 07/15/2008
• Est. Priority Date: 12/28/2004
• Status: Expired due to Fees

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Gharib, Morteza, Rinderknecht, Derek, Tasooji, Matthew
• Primary Examiner(s): Flanigan; Allen J.
• Application Number:
  US11/320,167
• Publication Number:
  US 20060196642A1
• Time in Patent Office: 931 Days
• Field of Search: 165/80.4, 165/104.33, 361/699
• US Class Current: 165/80.4
• CPC Class Codes: H01L 23/473 by flowing liquids H01L23/4332, H01L23/4338 take precedence
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/3011 Impedance

Abstract

A heat producing device is placed in contact with a heat exchanger that is fluidically coupled to a fluid pump. The fluid pump operates to pumps fluid through a closed fluidic system between the heat exchanger and a spot where the heat can be dissipated. In an aspect, an actuator forces fluid to be pumped without passing through a wall of the pump. One aspect uses an impedance pump as the pumping element.

Claims

1. An apparatus, comprising:

an electronically operated device;

a fluid filled conduit, thermally in contact with at least a portion of said heat producing device, and includes a fluid therein;

a pump, of a type that pumps said fluid through the conduit, but does not extend through any outer walls of the conduit to the inside of the conduit; and

wherein said fluid filled conduit includes a first portion forming said thermally contact, and includes a second portion which releases heat, wherein said conduit is formed of a plurality of mechanical segments having different fluidic characteristics, and said pump is an impedance pump that causes fluid to flow based on fluidic impedance differences between different mechanical segments of the conduit, and which includes an actuator that reduces an internal area of at least one area of the conduit to cause said fluid to flow,

and further comprising a controller which controls said actuator to a resonance point of the system that creates a maximum pumping effect.

2. An apparatus as in claim 1, wherein said electronically operated device includes an electronic device.

3. An apparatus as in claim 1, wherein said actuator is one of electromagnetic, piezoelectric, ferroelectric, electrostatic, based on actuation of a shape memory alloy, or based on actuation of a conducting polymer.

4. An apparatus as in claim 1, wherein said fluid filled conduit includes a heat exchanger at said first portion, exchanging heat with said electronically operated device.

5. An apparatus as in claim 1, wherein said fluid filled conduit includes a heat sink, at said second portion, operating to release heat.

6. An apparatus as in claim 5, wherein said heat sink is an active heat sink.

7. An apparatus as in claim 1, further comprising at least one temperature sensor, and wherein said controller operates based on information received from said temperature sensor.

8. An apparatus as in claim 1, further comprising a microfluidic mixer, fluidly coupled to the fluid filled conduit, that maximizes an amount of thermal mixing within a fluid within the fluid filled conduit.

9. An apparatus, comprising:

a chip formed of a substrate with at least one electronically operated device thereon;

a fluid filled conduit, also formed on said chip, and having a first portion which is thermally in contact with at least one portion of said electronically operated device, and at least another portion forming a heat releasing portion; and

a pumping part, operating to pump fluid in the chip without having any portion extending inside walls of said fluid filled conduit, wherein said conduit is formed of a plurality of mechanical segments having different fluidic characteristics, and said pumping part includes an impedance based pump that causes fluid to be pumped based on fluidic impedance differences between different mechanical segments forming the conduit, wherein said impedance pump further includes an actuator that causes a pressure increase in at least one area of at least one of said mechanical segments; and

a controller, that controls a characteristic of said actuator, to change a characteristic of pumping, wherein said controller controls said actuaotor to operate said pumping part intermittently and in bursts.

10. An apparatus as in claim 9, further comprising a temperature sensor, sensing a temperature associated with several electronically operated device, and increasing an amount of pumping when said temperature increases.

14. An apparatus as in claim 9, further comprising a microfluidic mixer, fluidly coupled to the fluid filled conduit, and that maximizes an amount of thermal mixing within a fluid that is within the fluid filled conduit.

11. A method, comprising:

forming a fluid filled conduit having at least one portion in contact with a heat producing device;

pumping fluid through the conduit without using any part that extends inside walls of the conduit, to draw heat from said at least one portion, and to pump said heat to at least a second portion; and

cooling said fluid at said second portion, wherein said pumping comprises using a conduit having a plurality of mechanical segments with different fluidic characteristics,

actuating at least one of said mechanical segments to cause fluid to flow between the different mechanical segments based on said different fluidic characteristics; and

controlling said actuating to a resonant point of the system that produces a maximum pumping effect.

12. A method as in claim 11, further comprising sensing a heat associated with said heat producing device, and controlling an amount of said pumping based on said sensing.

13. A method as in claim 11, wherein said forming comprises forming a heat exchanger in contact with said heat producing device.

15. A method as in claim 11, further comprising mixing fluid within said fluid filled conduit.