Heat exchange device

Abstract

A heat exchange device includes a tubular outer body having an outer wall confining a receiving space, a tubular inner body disposed in the receiving space and having an inner wall with an inner wall surface, a liquid chamber containing a heat transfer liquid, a ventilating space defined within the inner wall, and a plurality of inner fins projecting into the ventilating space from the inner wall surface of the inner body.

Description

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority of Taiwanese Application No. 92115557, filed on Jun. 9, 2003.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The invention relates to a heat exchange device, more particularly to a heat exchange device that can dissipate heat quickly.

[0004] 2. Description of the Related Art

[0005] Referring to FIG. 1, a conventional heat exchange device 1 includes a main body 11 with an inner chamber 111, a top cover (not shown) and a flat bottom seat (not shown) respectively sealing the inner chamber 111, a filling tube (not shown) positioned at the center of the top cover and in fluid communication with the inner chamber 111, and a heat transfer fluid (not shown) disposed in the inner chamber 111. A plurality of fins 112 extend from the outer periphery of the main body 11 and extension parts 114 that radiate from the main body 11. In use, the bottom seat is seated on a heat source, such as a central processing unit (CPU) or an integrated circuit (IC). The heat from the heat source is transmitted toward the main body 11 through the bottom seat.

[0006] As the fluid absorbs heat, it vaporizes and carries the heat away from the heat source. The fins 112 serve to dissipate the heat from the fluid, the main body 11, and the extension parts 114.

[0007] Although the aforesaid heat exchange device 1 can achieve its intended purpose, there is a need to provide a heat exchange device with a more reliable structure.

SUMMARY OF THE INVENTION

[0008] Therefore, the object of the present invention is to provide a heat exchange device that can dissipate heat quickly and that has a more reliable structure.

[0009] According to this invention, a heat exchange device comprises a tubular outer body having an outer wall confining a receiving space, a tubular inner body disposed in the receiving space and having an inner wall, a liquid chamber defined between the outer wall and the inner wall and containing a heat transfer liquid, a ventilating space defined within the inner wall of the inner body, and a plurality of inner fins. The inner wall is spaced apart from the outer wall, and includes an outer wall surface confronting the outer wall, and an inner wall surface opposite to the outer wall surface. The ventilating space is open at two axially opposed ends of the inner wall. The inner fins project into the ventilating space from the inner wall surface of the inner body.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiments with reference to the accompanying drawings, of which:

[0011] FIG. 1 is a perspective view of a main body of a conventional heat exchange device;

[0012] FIG. 2 is an exploded perspective view of the first preferred embodiment of a heat exchange device according to the present invention;

[0013] FIG. 3 is a perspective view of the first preferred embodiment in an assembled state;

[0014] FIG. 4 is a sectional view of the first preferred embodiment taken along line 4-4 of FIG. 3;

[0015] FIG. 5 is a fragmentary sectional view of FIG. 4, illustrating how heat transfer fluid changes phase after being stimulated by a heat source;

[0016] FIG. 6 is a perspective view of an inner body of the second preferred embodiment of a heat exchange device according to the present invention;

[0017] FIG. 7 is a perspective view of an inner body of the third preferred embodiment of a heat exchange device according to the present invention;

[0018] FIG. 8 is a perspective view of an inner body of the fourth preferred embodiment of a heat exchange device according to the present invention;

[0019] FIG. 9 is a perspective view of an inner body of the fifth preferred embodiment of a heat exchange device according to the present invention;

[0020] FIG. 10 is a fragmentary sectional view of a first sealing ring of the sixth preferred embodiment of a heat exchange device according to the present invention that incorporates a sealing member; and

[0021] FIG. 11 is a schematic view of the seventh preferred embodiment of a heat exchange device according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Before the present invention is described in greater detail, it should be noted that like elements are denoted by the same reference numerals throughout the disclosure.

[0023] Referring to FIGS. 2 to 5, the first preferred embodiment of a heat exchange device 3 according to the present invention is shown to comprise a tubular outer body 5, a tubular inner body 6, first and second sealing rings 8, 9, a filling tube 100, a heat transfer fluid 110, and a fan unit 120.

[0024] The tubular outer body 5 is adapted to be mounted on a heat source 4 (see FIG. 5), and is made of a good heat conductive material, such as aluminum, copper or a metal alloy. The outer body 5 has an outer wall 55 confining a receiving space 551. The outer wall 55 has a flat contact surface 51 that is adapted to be mounted on the heat source 4, a serrated surface 53 (see FIG. 4) formed opposite to the contact surface 51, and a plurality of outer fins 57 projecting outwardly from the outer wall 55.

[0025] The tubular inner body 6 is disposed in the receiving space 55, and is made of a good heat conductive material, such as aluminum, copper or a metal alloy. The inner body 6 has an inner wall 61 spaced apart from the outer wall 55. The inner wall 61 includes an outer wall surface 63 confronting the outer wall 55 of the outer body 5, an inner wall surface 64 opposite to the outer wall surface 63, a ventilating space 66 defined within the inner wall 61, and a plurality of inner fins 65 projecting into the ventilating space 66 from the inner wall surface 64. The outer and inner wall surfaces 63, 64 are formed respectively with a plurality of capillary grooves 631, 641 that extend axially of the inner body 6. In this embodiment, each of the capillary grooves 631 in the outer wall surface 63 has a triangular cross-section. The ventilating space 66 is open at two axially opposed ends of the inner wall 61. The inner fins 65 project radially from the inner wall surface 64, and have innermost ends 652 which define cooperatively an axial hole within the ventilating space 66. Each of the inner fins 65 is formed with a plurality of capillary grooves 651 in surfaces thereof that extend axially of the inner body 6 so as to enhance the heat transfer effect. The contact surface 51 of the outer wall 55 extends along an axial direction of the ventilating space 66.

[0026] Two spacer elements 56, 56′ are disposed between the outer wall 55 of the outer body 5 and the inner wall 61 of the inner body 6. In this embodiment, each spacer element 56, 56′ projects from the outer wall 55 to the inner wall 61. The spacer element 56 is tapered and serrated, and is formed integrally with the serrated surface 53 of the outer wall 55. The spacer element 56′ is semi-circular in cross-section, as best shown in FIG. 4, and is disposed opposite to the tapered spacer element 56. The inner wall 61 is further formed with two recesses 62, 62′ (see FIG. 4) for engaging respectively the spacer elements 56, 56′ so that the inner body 6 is positioned relative to the outer body 5. One of the recesses 62 is formed with serrations to engage the serrations of the tapered spacer element 56. As such, a liquid chamber 7 (see FIG. 4) is defined between the outer wall 55 of the outer body 5 and the inner wall 61 of the inner body 6. The liquid chamber 7 is formed with a liquid accumulating portion 73 that is proximate to the contact surface 51 of the outer wall 55 of the outer body 5.

[0027] The first and second sealing rings 8, 9 seal respectively two axially opposed ends of the liquid chamber 7. Each of the first and second sealing rings 8, 9 has a T-shaped cross-section.

[0028] The filling tube 100 is connected to the first seal ring 8, and has a first end section 101 extending into the liquid chamber 7, and a second end section 102 projecting out of the first seal ring 8.

[0029] The heat transfer fluid 110 is a conventional fluid that vaporizes when heated and that condenses when cooled. The fluid 110 is introduced into the liquid chamber 7 through the filling tube 100, and is accumulated in the liquid accumulating portion 73 of the liquid chamber 7, after which, a filling hole (not shown) in the filling tube 100 is sealed by a spot welding process. The fan unit 120 is connected fixedly to one end of the outer body 5 by means of a plurality of screws 150, and is associated with the ventilating space 66. A retaining hole 121 is formed in a frame 122 of the fan unit 120 for engaging and limiting the second end section 102 of the filling tube 100 therein.

[0030] The heat exchange device 3 further comprises a semi-circular guide block 130 engaging the innermost ends 652 of the inner fins 65 and covering the axial hole within the ventilating space 66. The guide block 130 guides air currents from the fan unit 120 to blow toward the inner fins 65 so as to carry the heat away from the inner fins 65.

[0031] When the heat source 4 generates heat, the heat transfer fluid 110 in the fluid accumulating portion 73 changes phase quickly, that is, from liquid to high-pressure vapor form, as shown by upward arrows in FIG. 5. Then, through the capillary action of the capillary grooves 631 in the outer wall surface 63 of the inner wall 61 of the inner body 6, the vaporized fluid falls into the capillary grooves 631, as shown by the arrows pointing to the capillary grooves 631 in FIG. 5, exchanges heat with the ambient space by convection, and subsequently condenses and flows downward due to gravity to the liquid accumulating portion 73, as shown by downward arrows in FIG. 5.

[0032] Furthermore, the presence of the capillary grooves 631 in the outer wall surface 631 of the inner body 6 not only can expedite cooling of the vaporized fluid, but can also enhance the heat transfer effect. Moreover, due to the outer fins 57 which can exchange heat with the surrounding air to dissipate heat outwardly, and due to the fan unit 120 which blows air towards the inner fins 65 so as to dissipate the heat within the inner body 6 of the heat exchange device 3, the heat from the heat source 4 is rapidly dissipated from the heat exchange device 3 of the present invention, thereby achieving a good heat exchanging effect.

[0033] Referring to FIG. 6, the second preferred embodiment of a heat exchange device according to the present invention is shown to be substantially similar to the first preferred embodiment. However, in this embodiment, the outer wall surface 63′ of the inner body 6′ is serrated, and is formed with a plurality of capillary grooves 631′, as shown in FIG. 6.

[0034] Referring to FIG. 7, the third preferred embodiment of a heat exchange device according to the present invention is shown to be substantially similar to the first preferred embodiment. Unlike the first preferred embodiment, each of the capillary grooves 631″ in the outer wall surface 63″ of the inner body 6″ has a trapezoidal cross-section.

[0035] Referring to FIG. 8, the fourth preferred embodiment of a heat exchange device according to the present invention is shown to be substantially similar to the first preferred embodiment. However, in this embodiment, the capillary grooves 631a in the outer wall surface 63a of the inner body 6a extend spirally of the outer wall surface 63a.

[0036] Referring to FIG. 9, the fifth preferred embodiment of a heat exchange device according to the present invention is shown to be substantially similar to the first preferred embodiment. However, in this embodiment, the capillary grooves 631b in the outer wall surface 63b of the inner body 6b extend circumferentially of the outer wall surface 63b.

[0037] Referring to FIG. 10, the sixth preferred embodiment of a heat exchange device 3 according to the present invention is shown to be substantially similar to the first preferred embodiment. However, in this embodiment, the first seal ring 8 has a hole 81 and a cover member 140 sealing the hole 81. The cover member 140 has an inner side 142 facing the liquid chamber 7, an outer side 141 opposite to the inner side 142, and a filling hole 143 formed in the cover member 140, in fluid communication with the liquid chamber 7, and extending through the outer side 141. The filling hole 143 is formed as a blind hole 144 which opens at the outer side 141 and which has a closed end 145 adjacent to the inner side 142. The cover member 140 further has a seat part 146 at the inner side 142 to bound the closed end 145. The seat part 146 has a first needle hole 147 extending through the inner side 142 and communicated with the blind hole 144.

[0038] In this embodiment, the heat exchange device 3 is not provided with the filling tube 100, but further comprises an elastic sealing member 150 fitted within the filling hole 143, and a securing member 160 disposed fittingly in the blind hole 144 and outwardly of the sealing member 150 so that an outer surface 161 of the securing member 160 is flush with the outer side 141 of the cover member 140. The securing member 160 has a shape in conformity with that of the blind hole 144, and includes a second needle hole 162 in alignment with the first needle hole 147, and an insert piece 180 disposed sealingly in the second needle hole 162. To fill the heat exchange device 3 with the heat transfer fluid 110, a needle 170 is extended into the liquid chamber 7 by passing through the second needle hole 162, the sealing member 150, and the first needle hole 147, and subsequently evacuates air from within the liquid chamber 7 and introduces a predetermined amount of the heat transfer fluid 110 into the liquid chamber 7. When the needle 170 is withdrawn from the sealing member 150, the latter, because of its elasticity, contracts to seal the passage of the needle 170 in the sealing member 150. Afterwards, the securing member 160 is fitted sealingly into the blind hole 144, thereby sealing the first needle hole 147 and preventing air from entering the liquid chamber 7 in the heat exchange device 3. At this time, the second needle hole 162 is closed by the insert piece 180 for enhanced airtight sealing. The insert piece 180 may be a welding spot formed by a spot welding machine (not shown).

[0039] Referring to FIG. 11, the seventh preferred embodiment of a heat exchange device 3 according to the present invention is shown to be substantially similar to the first preferred embodiment. However, in this embodiment, the heat exchange device 3 has two ends connected respectively to a water inlet pipe 190 and a water outlet pipe 200. The heat generated by the heat source 4 is rapidly transferred to the water (not shown) that enters the inner body 6 (see FIG. 2) through the inlet pipe 190, so that warm water exits the heat exchange device 3 through the outlet pipe 200. Such a structure can be employed in a water heater.

[0040] While the present invention has been described in connection with what is considered the most practical and preferred embodiments, it is understood that this invention is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.

Claims

1. A heat exchange device comprising:

a tubular outer body having an outer wall confining a receiving space;

a tubular inner body disposed in said receiving space and having an inner wall, said inner wall being spaced apart from said outer wall and including an outer wall surface confronting said outer wall and an inner wall surface opposite to said outer wall surface;

a liquid chamber defined between said outer wall and said inner wall and containing a heat transfer liquid;

a ventilating space defined within said inner wall of said inner body, said ventilating space being open at two axially opposed ends of said inner wall; and

a plurality of inner fins projecting into said ventilating space from said inner wall surface of said inner body.

2. The heat exchange device as claimed in claim 1, further comprising a spacer element disposed between said outer wall and said inner wall.

3. The heat exchange device as claimed in claim 2, wherein said spacer element projects from said outer wall to said inner wall, said inner wall having a recess to engage said spacer element.

4. The heat exchange device as claimed in claim 1, further comprising a plurality of outer fins projecting outwardly from said outer wall of said outer body.

5. The heat exchange device as claimed in claim 1, further comprising a fan unit disposed at one of said axially opposed ends of said inner wall and associated with said ventilating space.

6. The heat exchange device as claimed in claim 5, wherein said inner fins project radially from said inner wall surface of said inner wall and have innermost ends which define cooperatively an axial hole within said ventilating space, said heat exchange device further comprising a guide block covering said axial hole and engaging said innermost ends.

7. The heat exchange device as claimed in claim 6, wherein said outer wall has a contact surface which is adapted to be mounted on a heat source and which extends along an axial direction of said ventilating space.

8. The heat exchange device as claimed in claim 1, further comprising first and second sealing rings to seal respectively two axially opposed ends of said liquid chamber.

9. The heat exchange device as claimed in claim 8, further comprising a filling tube that is connected to said first seal ring and that extends into said liquid chamber, the heat transfer liquid being introduced into said liquid chamber through said filling tube.

10. The heat exchange device as claimed in claim 1, further comprising a plurality of capillary grooves formed in said outer wall surface of said inner wall.

11. The heat exchange device as claimed in claim 10, wherein said capillary grooves extend axially of said inner body.

12. The heat exchange device as claimed in claim 10, wherein said capillary grooves extend spirally of said inner body.

13. The heat exchange device as claimed in claim 10, wherein said capillary grooves extend circumferentially of said inner body.

14. The heat exchange device as claimed in claim 1, further comprising a plurality of capillary grooves formed in said inner wall surface of said inner wall and in a surface of each of said inner fins.

15. The heat exchange device as claimed in claim 14, wherein said capillary grooves extend axially of said inner body.