US20050257916A1

US20050257916A1 - Heat conductive pipe

Info

Publication number: US20050257916A1
Application number: US11/014,427
Authority: US
Inventors: Charles Leu; Ga-Lane Chen; Tai-Cherng Yu
Original assignee: Hon Hai Precision Industry Co Ltd
Current assignee: Hon Hai Precision Industry Co Ltd
Priority date: 2004-05-18
Filing date: 2004-12-17
Publication date: 2005-11-24
Also published as: CN100383960C; CN1700455A

Abstract

A heat conductive pipe (1) includes a heat conductive body (3), a quantity of working fluid (4) contained in the body, and a chamber (610). The body defines a first end and a second end. The chamber is located at one end of the body. The volume of the chamber is changeable under control, wherein the working fluid flows from the first end to the second end when the volume is increasing and the working fluid flows from the second end to the first end when the volume is decreasing.

Description

TECHNICAL FIELD

The present invention relates to a heat conductive pipe, and particularly to a heat conductive pipe which can efficiently dissipate heat from an electronic component.

BACKGROUND

As computer technology continues to advance, electronic components such as central processing units (CPUs), power supply units (PSUs) of computers are made to provide faster operational speeds and greater functional capabilities. When a CPU/PSU operates at a high speed in a computer enclosure, its temperature increases greatly. It is desirable to dissipate the heat generated by the CPU/PSU quickly.
Heat pipes have been suggested for cooling electronic components. Conventionally, a heat pipe comprises an evaporator to take in heat and a condenser to expel heat. Working fluid is contained in the heat pipe to transfer heat from the evaporator to the condenser. The heat entering the evaporator of the heat pipe boils the fluid and turns it into a vapor. The vapor expands in volume and travels to the condenser where it condenses to a liquid and gives up its heat. The liquid is then returned to the evaporator by gravity or a wick and starts the process again.
A conventional heat pipe does not work until electronic components to be cooled reach a certain high enough temperature, in general, between 30° C. and 40° C., to evaporate the working fluid. Thus, the electronic components must operate at a temperature at least above 30° C. A solution to decrease the threshold temperature of the working fluid is to heighten vacuum inside of the heat pipe. However, this requires high rigidity materials for the heat pipe shell and increases manufacturing cost of the heat pipe, or else, the heat pipe is prone to be damaged and a leak may be formed to increase the vacuum pressure of the heat pipe. As a result, the heat pipe fails to work.
A conventional heat pipe has a variety of other limitations, such as capillary pumping limit, nucleate boiling limit and entrainment limit, constraining the ability of the heat pipe to cool the electronic components. The heat pipe stops operating when each of the limitations is reached.
Thus, an improved heat conductive pipe which can efficiently conduct heat from a heat generating component is desired.

SUMMARY OF THE INVENTION

Accordingly, an object of the present invention is to provide a heat conductive pipe which can efficiently conduct heat from a heat generating component.
To achieve the above-mentioned object, a heat conductive pipe comprises a heat conductive body, a quantity of working fluid contained in the body, and a chamber. The body comprises a first end and a second end. The chamber is located at one end of the body. The volume of the chamber is changeable under control, wherein the working fluid flows from the first end to the second end when the volume is increasing and the working fluid flows from the second end to the first end when the volume is decreasing.
Other objects, advantages and novel features of the present invention will be drawn from the following detailed description of two preferred embodiments of the present invention with attached drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partially cross section view of a heat conductive pipe in accordance with a preferred embodiment of the present invention, along an axis of the heat conductive pipe;
FIG. 2 is similar to FIG. 1, but showing next state disposed inside of the heat conductive pipe; and
FIG. 3 is a partially cross section view of a heat conductive pipe in accordance with another embodiment of the present invention.

DATAILED DESCRIPTION OF A PREFERRED EMBODIMENT

FIGS. 1-2 show a heat conductive pipe 1 in accordance with a preferred embodiment of the present invention. The heat conductive pipe 1 comprises an electromagnetism switch 2, a heat conductive body 3, and a quantity of working fluid 4 contained in the body 3.
The heat conductive body 3 comprises an evaporator 30 at one end thereof and a condenser 40 at the opposite end thereof. The body 3 further comprises a pump 60 (shown as in the broken line) located at one end, near the evaporator 30 or the condenser 40 of the body 3. For convenient description, the pump 60 will be described as being at the end near the evaporator 30. The pump 60 comprises a seat member 600 by which the pump 60 is fixed onto the body 3, and a first membrane 602. The first membrane 602 is secured to a side of the seat member 600, opposing inside of the body 3.
The seat member 600 comprises an upper seat 604, a lower seat 606, and a second membrane 608 sandwiched between the upper seat 604 and the lower seat 606. The first and second membranes 602, 608 corporately define a chamber 610 therebetween. A plurality of inlets 612 and outlets 614 extend through the upper seat 604, the lower seat 606 and the second membrane 608, to communicate the chamber 610 with an inside of the body 3. Furthermore, a plurality of baffles 616 extending from the lower seat member 606 are in front of each of the inlets 612 and the outlets 614 respectively. This precaution can protect the inlets 612 or the outlets 614 from being damaged by the impingement of the working fluid 4. Alternatively, the upper seat 604 can be omitted and the first membrane 602 can be directly attached to the second membrane 608 or the lower seat 606 to secure the first membrane 602 on the seat member 600.
The first membrane 602 is secured on the upper seat 604 with its outer periphery, shown as AB, CD. The first membrane 602 is made of magnetism material, such as FeNi, and is controlled by the switch 2 to move back and forth. Alternatively, other actuator can be used instead of the switch 2 to drive the first membrane 602 to move to change the volume of the chamber 610. The volume of the chamber 610 changes due to the movement of the first membrane 602. The working fluid 4 is sucked into the chamber 610 when the volume of the chamber 610 is inflated, and is impelled from the chamber 610 when the volume of the chamber is deflated. Simultaneously, the movement of the working fluid 4 between the evaporator 30 and the condenser 40 is accelerated.
In operation of the heat conductive pipe 1, the switch 2 generates a first magnetic field to magnetize the first membrane 602 towards a direction to increase the volume of the chamber 610. The chamber 610 is inflated so that the pressure in the chamber 610 becomes lower than that inside the body 3. The inlets 612 are opened, while the outlets 614 are closed. The working fluid 4 is pumped into the chamber 610 through the inlets 612, until an average pressure occurs inside the chamber 610 and the body 3. As a result, the working fluid 4 cooled in the condenser 40 is forced to flow to the evaporator 30.
Next state, the switch 2 generates a second magnetic field to magnetize the first membrane 602 towards a direction to decrease the volume of the chamber 610. The chamber 610 is deflated so that the pressure in the chamber 610 becomes higher than that inside the body 3. The outlets 614 are opened, while the inlets 612 are closed. The working fluid 4 is impelled from the chamber 610 through the outlets 614, until an average pressure occurs inside the chamber 610 and the body 3. As a result, the working fluid 4 pumped into the chamber 610 is forced to flow to the condenser 40.
In the present invention, the pump 60 is provided to drive the working fluid 4 to circulate between the evaporator 30 and the condenser 40. The working fluid 4 heated in the evaporator 30, evaporated or not, is accelerated to flow to the condenser 40 to dissipate the heat. The working fluid 4 cooled in the condenser 40 is accelerated to flow to the evaporator 30 to cool down the evaporator 30. Therefore, the present heat conductive pipe 1 can efficiently cool down an electronic components (not shown) at a desired low temperature even if the electronic components don't reach the temperature to vaporize the working fluid 4. The heat conductive pipe 1 can cool the electronic components more efficiently. Furthermore, the present invention can eliminate the heat pipe limits.
FIG. 3 illustrates an alternative heat conductive pipe 1′ of the present invention. The structure of the heat conductive pipe 1′ is substantially similar to that of the heat conductive pipe 1 in the preferred embodiment. The primary difference of the heat conductive pipe 1′ from the heat conductive pipe 1 is that the second membrane 608′ cooperating with the outlet 614′ is disposed beneath the seat member 600′.
It is understood that the invention may be embodied in other forms without departing from the spirit thereof. Thus, the present examples and embodiments are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein.

Claims

1. A heat conductive pipe comprising:

a heat conductive body comprising a first end and a second end;

a quantity of working fluid contained in the body; and

a chamber located at one end of the body, the volume of the chamber being changeable under control;

wherein the working fluid flows from the first end to the second end when the volume is increasing and the working fluid flows from the second end to the first end when the volume is decreasing.

2. The heat conductive pipe as claimed in claim 1, wherein the chamber further comprises at least one inlet and at least one outlet, wherein the chamber communicates with an inside of the body through the inlet and the outlet.

3. The heat conductive pipe as claimed in claim 1, wherein the chamber is defined by a seat member secured on the body, and a first membrane secured on the seat member.

4. The heat conductive pipe as claimed in claim 3, wherein the first membrane can move back and forth under control to cause the volume of the chamber to change such that the working fluid is accelerated to flow back and forth between the first end and second end of the body.

5. The heat conductive pipe as claimed in claim 4, wherein the first membrane is controlled by an actuator.

6. The heat conductive pipe as claimed in claim 3, wherein the first membrane is made from NiFe.

7. The heat conductive pipe as claimed in claim 3, wherein the seat member comprises an upper seat, a lower seat secured on the body, and a second membrane sandwiched between the upper seat and the lower seat.

8. The heat conductive pipe as claimed in claim 7, wherein the chamber further comprises at least one inlet and at least one outlet, the inlet and the outlet defined on the second membrane and the seat member, wherein the chamber communicates with an inside of the body through the inlet and the outlet.

9. The heat conductive pipe as claimed in claim 8, wherein the seat membrane further comprises:

at least one first baffle located before the inlet; and

at least one second baffle located before the outlet,

wherein the first baffle and the second baffle extend from the seat member protecting the inlet and the outlet from being damaged by the impingement of the working fluid.

10. The heat conductive pipe as claimed in claim 3, wherein the seat member comprises an upper seat, a lower seat secured on the body, and a second membrane attached on the seat, the second membrane comprising:

a first part, sandwiched between the upper seat and the lower seat; and

a second part, extending from a side of the lower seat opposing inside of the body.

11. A heat conductive pipe comprising:

a heat conductive body comprising a first end and a second end;

a quantity of working fluid contained in the body; and

a pump located within the body, the pump comprising:

at least one inlet; and

at least one outlet;

wherein the pump is capable of sucking the working fluid thereinto via the inlet to accelerate the working fluid to flow from the first end to the second end, and of discharging the working fluid therein via the outlet to accelerate the working fluid to flow back.

12. The heat conductive pipe as claimed in claim 11, wherein the pump further comprises:

a seat member, by which the pump is secured on the body; and

a first membrane attached on the seat membrane, wherein the seat member and the first membrane forms a chamber receiving the working fluid, and the volume of the chamber is changeable under control to provide a force to flow the working fluid.

13. The heat conductive pipe as claimed in claim 12, wherein the seat member comprises:

an upper seat;

a lower seat attached on the body; and

a second membrane sandwiched between the upper seat and the lower seat,

wherein the inlets and the outlets are defined by the upper seat, the lower seat and the second membrane.

14. A heat conductive pipe comprising:

a heat conductive body comprising a first end and a second end;

a quantity of working fluid contained in the body; and

means for accelerating the working fluid to flow back and forth between the first end and second end of the body.

15. The heat conductive pipe as claimed in claim 14, wherein the means comprises a pump located in the body, the pump comprising:

at least one inlet; and

at least one outlet, wherein the pump is capable of driving the working fluid to circuit between the first end and the second end in a manner that the working fluid is pumped into the chamber through the inlet when the volume is inflated, and then impelled out through the outlet to flow back when the volume is deflated.

16. The heat conductive pipe as claimed in claim 14, wherein the chamber is defined by a seat member and a first membrane attached on the seat membrane, wherein the first membrane can move back and forth under control to change the volume of the chamber.

17. The heat conductive pipe as claimed in claim 16, wherein the first membrane is made of NiFe, and is controlled to move by an actuator.

18. The heat conductive pipe as claimed in claim 17, wherein the actuator is an electromagnetism switch.