BACKGROUND
1. Technical Field
The present disclosure relates to plate-type heat pipes, and more particularly, to a plate-type heat pipe having stable and reliable performance and a method for manufacturing such plate-type heat pipe.
2. Description of Related Art
Generally, plate-type heat pipes are used to absorb heat generated by electronic components and transfer and/or dissipate the heat elsewhere. A typical plate-type heat pipe includes a plate-shaped container, a wick structure formed on inner surfaces of the container, and working fluid sealed inside the container. The container is prone to be deformed when it is pressed accidentally or when the working fluid is vaporized, thereby adversely affecting the stable performance of the plate-type heat pipe.
What is needed, therefore, is a plate-type heat pipe which can overcome the limitations described, and a method for manufacturing such a plate-type heat pipe.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded, isometric view of a plate-type heat pipe in accordance with an embodiment of the present disclosure.
FIG. 2 is an assembled, side cross-sectional view of the plate-type heat pipe of FIG. 1.
FIG. 3 is a side cross-sectional view showing a first mold accommodating a condensing plate of the plate-type heat pipe of FIG. 1.
FIG. 4 is similar to FIG. 3, but showing a first wick structure of the plate-type heat pipe of FIG. 1 being formed on the condensing plate.
FIG. 5 is an isometric view of a first mold portion of a second mold, which is used for forming a second wick structure of the plate-type heat pipe of FIG. 1.
FIG. 6 is an isometric view of a second mold portion of the second mold, showing the second mold portion inverted.
FIG. 7 is a side cross-sectional view showing the first and second mold portions of the second mold coupled together and accommodating an evaporating plate of the plate-type heat pipe of FIG. 1.
FIG. 8 is similar to FIG. 7, but showing a second wick structure of the plate-type heat pipe of FIG. 1 being formed on the evaporating plate.
DETAILED DESCRIPTION
A method for manufacturing a plate-type heat pipe in accordance with an embodiment of the present disclosure includes steps of: a) providing a first metallic sheet, a second metallic sheet, and a supporting portion; b) arranging the supporting portion between the first metallic sheet and the second metallic sheet; and c) welding the first and second metallic sheets together, thereby obtaining a hermetical container, the supporting portion abutting against and connecting with the first and second metallic sheets. Exemplary details of the method are given below.
Referring to FIGS. 1-2, in a typical application, the method is used to manufacture a plate-type heat pipe which includes an elongated condensing plate 11, a tray-shaped evaporating plate 13, a first wick structure 12, a second wick structure 14, and a plurality of supporting portions 15. The condensing plate 11 hermetically contacts the evaporating plate 13. The evaporating plate 13 is adapted for absorbing heat generated by one or more components (not shown) such as electronic devices. The condensing plate 11 dissipates heat, transferred from the evaporating plate 13, to the ambient environment. The first wick structure 12 is adhered on an inner surface of the condensing plate 11. The second wick structure 14 is adhered on an inner surface of the evaporating plate 13. Each of the supporting portions 15 is a sphere and abuts against the inner surfaces of the condensing plate 11 and the evaporating plate 13, respectively. The condensing plate 11, the evaporating plate 13 and the supporting portions 15 are formed from metallic material which can be soldered and which transfers heat well. In this embodiment, the condensing plate 11, the evaporating plate 13 and the supporting portions 15 are made of copper.
The evaporating plate 13 includes a rectangular heat absorbing portion 131, four sidewalls 133, and two extending portions 135. The sidewalls 133 perpendicularly extend upwardly from four edges of the heat absorbing portion 131. The extending portions 135 extend outwardly along opposite horizontal directions from top portions of two opposite sidewalls 133, respectively. The extending portions 135 are perpendicular to the sidewalls 133. Top surfaces of the extending portions 135 and top ends of two corresponding sidewalls 133 interconnecting the extending portions 135 are all coplanar with one another.
The second wick structure 14 includes a first wick portion 141 and four second wick portions 143. The first wick portion 141 is adhered on an inner surface of the heat absorbing portion 131. The second wick portions 143 are adhered on inner surfaces of the sidewalls 133, respectively. The top surfaces of the extending portions 135 and the top ends of the two corresponding sidewalls 133 hermetically connect a periphery of a bottom surface of the condensing plate 11. Four lateral side edges of the first wick structure 12 connect with inside surfaces of top ends of the second wick portions 143 of the second wick structure 14, respectively. The supporting portions 15 extend through the first wick structure 12 and the first wick portions 141 to directly abut against the condensing plate 11 and the heat absorbing portion 131 of the evaporating plate 13, respectively.
Referring also to FIGS. 3-4, the first wick structure 12 is sintered copper powder made in a first mold 20, and the second wick structure 14 is sintered copper powder made in a second mold 40, as shown in FIGS. 5-8.
The first mold 20 includes a first mold portion 21, and a second mold portion 23 matching with the first mold portion 21. The first mold portion 21 includes a top plate 213 and four elongated, spaced pressing walls 215 extending perpendicularly downwardly from an inner surface of the top plate 213. The second mold portion 23 is a rectangular container, and includes a supporting plate 231 and four baffling plates 233 extending perpendicularly upwardly from four edges of the supporting portion 231. A space (not labeled) is thus defined among the baffling plates 233 over the supporting plate 231.
The condensing plate 11 is received in the second mold portion 23, with lateral side edges of the condensing plate 11 abutting against inner surfaces of the baffling plates 233. Top ends of the baffling plates 233 protrude up beyond the condensing plate 11. The first mold portion 21 is coupled to the second mold portion 23, with the pressing walls 215 received in the space and engaging with inner sides of the baffling plates 233, respectively. The top ends of the baffling plates 233 abut against a periphery of the inner surface of the top plate 213. In such a state, bottom ends of the pressing walls 215 contact peripheral portions of the condensing plate 11. The pressing walls 215, the top plate 213 and the condensing plate 11 cooperatively define a rectangular first receiving chamber 30.
The copper powder is filled in the first receiving chamber 30 and is sintered to form the first wick structure 12 on a main central portion of the inner surface of the condensing plate 11.
The second mold 40 includes a first mold portion 41 and a second mold portion 43. Referring to FIG. 5, the first mold portion 41 includes an engaging plate 413, and a cuboid protruding portion 415 protruding from a central portion of the engaging plate 413. Therefore each of opposite lateral ends of the engaging plate 413 exposed beyond the protruding portion 415 forms a first pressing portion 414, and each of two opposite front and rear ends of the engaging plate 413 exposed beyond the protruding portion 415 forms a second pressing portion 416. A size of each first pressing portion 414 is larger than that of the corresponding extending portion 135 of the evaporating plate 13. A size of each second pressing portion 416 is larger than that of the top end of the corresponding sidewall 133. A plurality of cylindrical receiving holes 4151 is defined in the protruding portion 415 to receive the supporting portions 15 therein. A height of the protruding portion 415 is less than a height of the sidewalls 133 of the evaporating plate 13. A length of the protruding portion 415 is less than a distance between the two corresponding sidewalls 133 of the evaporating plate 13. A width of the protruding portion 415 is less than a distance between the two corresponding sidewalls 133 of the evaporating plate 13. A diameter of each receiving hole 4151 is substantially equal to or slightly greater than a diameter of each supporting portion 15, and a depth of the receiving hole 4151 is less than the diameter of the supporting portion 15.
As shown in FIG. 6, the second mold portion 43 includes a supporting plate 431, two first extending plates 433 and two second extending plates 435. The first extending plates 433 are elongated, parallel to each other and extend upwardly from two opposite front and rear ends of the supporting plate 431. The second extending plates 435 are elongated, parallel to each other and extend upwardly from two opposite left and right lateral ends of the supporting plate 431. The second extending plates 435 perpendicularly interconnect the first extending plates 433. A height of the second extending plates 435 is less than that of the first extending plates 433. The difference between the heights of the second extending plates 435 and first extending plates 433 is generally equal to a thickness of the extending portions 135 of the evaporating plate 13. The supporting plate 431, the first extending plates 433 and the second extending plates 435 cooperatively define a receiving chamber 437 to receive the evaporating plate 13.
Referring to FIGS. 6 and 7, to form the second wick structure 14, the evaporating plate 13 is received in the receiving chamber 437 of the second mold portion 43 of the second mold 40, with the heat absorbing portion 131 of the evaporating plate 13 contacting the supporting plate 431 of the second mold portion 43. Bottom ends (as viewed in FIG. 7) of the second extending plates 435 abut against the extending portions 135 of the evaporating plates 13, respectively; and inner sides of the second extending plates 435 contact the two sidewalls 133 from which the extending portions 135 extend. The other two sidewalls 133 contact inner sides of the first extending plates 433, respectively. Bottom ends (as viewed in FIG. 7) of the extending portions 135, said other two sidewalls 133, and the first extending plates 433 are all coplanar with one another.
Referring to FIGS. 5 and 7, the supporting portions 15 are received in the receiving holes 4151 of the protruding portion 415 of the first mold portion 41.
Referring to FIG. 7, the first mold portion 41 and the second mold portion 42 are then coupled together. In this state, the first pressing portions 414 of the first mold portion 41 contact the extending plates 135 of the evaporating plate 13, respectively. The second pressing portions 416 press the bottom ends of said other two sidewalls 133 and the first extending plates 433. The protruding portion 415 is spaced from the heat absorbing portion 131, while the supporting portions 15 contact the heat absorbing portion 131. The sidewalls 133 of the evaporating plate 13 surround and are spaced from the protruding portion 415. A second receiving chamber 50 is thus defined between the evaporating plate 13 and the first mold portion 41.
Referring to FIG. 8, copper powder is then filled in the second receiving chamber 50 and is sintered to form the second wick structure 14. The supporting portions 15 also connect with the second wick structure 14 by the sintering of the copper powder. In one embodiment, the supporting portions 15 become integrally connected with the second wick structure 14.
After the first wick structure and the second wick structure 14 are formed, the first mold 20 and the second mold 40 are opened to obtain the condensing plate 11 and the evaporating plate 13. The condensing plate 11 and the evaporating plate 13 are then attached together by welding. The condensing plate 11 and evaporating plate 13 are brought into contact with each other, and then subjected to high temperature and high pressure for a period of time. As a result, the supporting portions 15 penetrate through the first wick structure 12, with opposite ends of the supporting portions 15 thereby abutting against both the condensing plate 11 and the evaporating plate 13.
It is to be understood, however, that even though numerous characteristics and advantages of various embodiments have been set forth in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
Patent Application
20110240264
