US20060207749A1

US20060207749A1 - Multi-layer wick structure of heat pipe

Info

Publication number: US20060207749A1
Application number: US11/082,803
Authority: US
Inventors: Hul-Chun Hsu
Original assignee: Jaffe Ltd
Current assignee: Jaffe Ltd
Priority date: 2005-03-18
Filing date: 2005-03-18
Publication date: 2006-09-21

Abstract

A multi-layer wick structure attached to a tubular member of a heat pipe includes a first weaving mesh of wick layer attached to an interior surface of the tubular member, and a second weaving mesh of wick layer encircled by the first wick layer so that the first wick layer is sandwich between the tubular member and the second wick layer. The first and the second weaving meshes of the wick layer include a plurality of first and second weaving wires, respectively, and the first weaving wire has the diameter smaller than that of the second weaving wire.

Description

BACKGROUND OF THE INVENTION

The present invention relates in general to a multi-layer wick structure of a heat pipe, and more particularly, to a multi-layer wick structure providing excellent capillary force and attachment to an interior surface of a heat pipe.
The heat pipe has been applied in various types of electronic products for delivering large amount of heat without consuming significant power because of the characteristics of high thermal transmission capacity, high thermal transmission speed, high thermal conduction efficiency, light weight, none mobile element, simple structure and versatile applications. Conventional heat pipe includes a wick structure attached to an interior surface of a heat-pipe body. The wick structure includes weaving mesh that has capillary effect, such that a working fluid filled in the heat-pipe body can be used to deliver heat. To improve the capillary force and the amount of heat to be transferred by the wick structure, multi-layer structure has been adapted in the heat pipe.
FIG. 1 shows a conventional weaving mesh of a wick structure la which is curled into a multi-layer structure. When the curled wick structure la is inserted into the heat pipe body 2 a, a sintering process is required to attach the curled wick structure 1 a to the internal surface of the heat-pipe body 2 a. However, as the weaving mesh of the wick structure 1 a is typically too soft to support itself. The multi-layer portion A formed by curling process makes the attachment worse. As there provides no additional support structure, the wick structure 1 a is easily softened and collapsed due to the heat generated in the high-temperature sintering process.
To resolve the problems caused by the conventional heat pipe structure as described above, the Applicant, with many years of experience in this field, has developed a shrinkage-free sealing method and structure of heat pipe as described as follows.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a multi-layer wick structure of a heat pipe with a finer weaving mesh of first wick layer attached inside the heat pipe and a coarser weaving mesh of the second wick layer supporting the first wick layer. Such that the multi-layer wick structure can provide the excellent capillary force and attachment to an interior surface of a heat pipe.
Accordingly, the multi-layer wick structure attached to a tubular member of a heat pipe includes a first weaving mesh of wick layer attached to an interior surface of the tubular member, and a second weaving mesh of wick layer encircled by the first wick layer so that the first wick layer is sandwich between the tubular member and the second wick layer. The first and the second weaving meshes of the wick layer include a plurality of first and second weaving wires, respectively, and the first weaving wire has the diameter smaller than that of the second weaving wire.
The objectives of the present invention will become obvious to those of ordinary skill in the art after reading the following detailed description of preferred embodiments.
It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The above objects and advantages of the present invention will be become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:
FIG. 1 shows an a cross sectional view of a conventional heat pipe;
FIG. 2 shows the process of winding a multi-layer wick structure;
FIG. 3 shows the process for inserting the wick structure into a tubular member of a heat pipe;
FIG. 4 shows the open circular profile of the winded multi-layer wick structure; and
FIG. 5 shows an enlarged view of a portion A in Figure.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
Referring to FIGS. 2-4, a multi-layer wick structure of a heat pipe is provided. The heat pipe includes a tubular member 1, a first wick layer 2 and a second wick layer 3.
As shown in FIG. 2, the first and the second wick layers 2 and 3 include a first and a second weaving meshes 20 and 30, respectively. In one preferred embodiment, the first wick layer 2 includes two first weaving meshes 20, and the second wick layer 3 includes one first weaving mesh 30. However, the first and the second wick layers 2 and 3 can both include a plurality of weaving meshes. After the first and the second wick layers 2 and 3 overlaying each other, the wick structure is winded with the first weaving meshes 20 encircling the second weaving mesh 30.
As shown in FIGS. 3 and 4, the winded first and the second wick layers 2 and 3 are disposed into the hollow tubular member 1. Such that the first wick layer 2 is sandwiched between the tubular member 1 and the second wick layer 3 and securely attached to an interior surface 10 of the tubular member 1.
Further referring to FIG. 5, the first and the second weaving meshes 20 and 30 includes a plurality of first and second weaving wires 200 and 300, respectively. Moreover, the diameter of the first weaving wire 200 is smaller than the diameter of the second weaving wire 300. The smaller weaving wires 200 are finer and softer to make the first weaving mesh 20 capably of providing excellent attachment to the interior surface 10 of the tubular member 1 and better capillary force to the working fluid filled in the tubular member 2, while the larger weaving wires 300 are coarser and harder to make the second weaving mesh 30 capably of providing better support effect of the wick structure. Therefore, during the high-temperature annealing process, the second weaving mesh 30 of the second wick layer 3 can provide sufficient support to the first weaving mesh 20 so that the first wick structure 2 is not easily softened and peeled from the interior surface 10 of the tubular member 1. Meanwhile, the second wick layer 3 can also provide more capillary force to transport the working fluid.
As the first wick layer 2 has the finer weaving wires 200 compared to the coarser weaving wires 300 of the second wick layer 3, the capillary force of the heat pipe is enhanced, while second wick layer 3 provides better support to the first wick layer 2 to ensure the first wick structure 2 can still attach on the interior surface 10 of the tubular member 1 without peeling at annealing.
While the present invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those of ordinary skill in the art the various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.

Claims

1. A multi-layer wick structure attached to a tubular member of a heat pipe, comprising:

a first wick layer having a plurality of first weaving meshes attached to an interior surface of the tubular member; and

a second wick layer having at least a second weaving mesh, which is encircled by the first wick layer so that the first wick layer is sandwiched between the tubular member and the second wick layer, wherein the first weaving mesh comprises a plurality of first weaving wires and the second weaving mesh comprises a plurality of second weaving wires, and the first weaving wire has the diameter smaller than that of the second weaving wire.

2. (canceled)

3. The structure of claim 1, wherein the second wick layer has a plurality of weaving meshes.