Patent Application
20130025829
1. Field of the Invention
The present invention relates to a vapor chamber, and in particular to a vapor chamber having a heated protrusion.
2. Description of Prior Art
A vapor chamber is a heat-conducting module that is widely used, which includes a flat casing, a working fluid filled in the flat casing, a wick structure formed on inner walls of the flat casing, and a supporting structure provided inside the flat casing. The supporting structure provides a sufficient strength to the flat casing to withstand external pressures, thereby protecting the flat casing from recessing due to the external pressures. In use, one surface of the vapor chamber contacting a heat-generating element is called as a heat-absorbing surface, and the other surface of the vapor chamber away from the heat-generating element is called as a heat-releasing surface. A portion of the working fluid in the vapor chamber adjacent to the heat-absorbing surface absorbs the heat generated by the heat-generating element to become vapor. The vapor-phase working fluid flows toward the heat-releasing surface on which it condenses to flow back to the heat-absorbing surface along the wick structure. With the vapor/liquid phase change and circulation of the working fluid in the wick structure, the heat generated by the heat-generating element can be conducted to the outside.
The inner walls of the vapor chamber are provided with the wick structure. The whole heat-absorbing surface can be used for conducting the heat. However, not the whole heat-absorbing surface is brought into thermal contact with the heat-generating element. Thus, a portion of the wick structure on the inner wall of the heat-absorbing surface not contacting the heat-generating element does not contribute to the heat conduction a lot. In other words, the remaining wick structure inevitably increases the production cost of the vapor chamber. If the wick structure could be concentrated on the heat-absorbing surface at a position corresponding to the heat-generating element, the efficiency of the wick structure will be increased and the production cost can be reduced.
On the other hand, with the advancement of science and technology, a plurality of heat-generating elements are arranged on a large printed circuit board. Since the thickness of each heat-generating element is different, the conventional vapor chamber having a flat heat-absorbing surface cannot surely contact every heat-generating element. As a result, several vapor chambers have to be disposed on the printed circuit board to correspond to the respective heat-generating element, which increases the production cost. Further, mounting these vapor chambers on the printed circuit board involves more steps.
Therefore, it is an important issue for the present Inventor to solve the above-mentioned problems.
The present invention is to provide a vapor chamber having a heated protrusion, in which a portion of the vapor chamber not contacting a heat-generating element is raised to facilitate the mounting and heat-dissipating of a heat-generating element.
The present invention is to provide a vapor chamber having a heated protrusion, in which a wick structure is provided at a position corresponding to the heat-generating element. By this arrangement, the heat-conducting efficiency of the wick structure is increased and the cost is reduced.
The present invention provides a vapor chamber configured to conduct heat generated by a heat-generating element and including:
a bottom plate, one side of the bottom plate having at least one heated protrusion brought into thermal contact with the heat-generating element, the other side thereof being formed with an accommodating trough corresponding to the heated protrusion;
a first wick structure provided in the accommodating trough;
a second wick structure disposed on the bottom plate, the second wick structure being provided with an opening corresponding to the accommodating trough and a plurality of airflow channels in communication with the opening;
a cover plate tightly covering the bottom plate;
a plurality of supporting posts located in the accommodating trough and sandwiched between the cover plate and the first wick structure; and
a working fluid filled between the cover plate and the bottom plate.
In comparison with prior art, the present invention has advantageous features as follows.
Since one side of the bottom plate has at least one heated protrusion brought into thermal contact with the heat-generating element, the peripheral dimension and thickness of the heated protrusion can be designed based on the peripheral dimension and thickness of the heat-generating element. In this way, the vapor chamber is formed with a plurality of heated protrusions of different thickness for conducting the heat generated by a plurality of heat-generating elements on a printed circuit board.
Since the other side of the bottom plate is formed with the accommodating trough corresponding to the heated protrusion, and the first wick structure is disposed in the accommodating trough, the size of the first wick structure can be controlled based on the peripheral dimension of the heat-generating element. Thus, the efficiency of the first wick structure is enhanced greatly, and the production cost is reduced.
Since the second wick structure has an opening corresponding to the accommodating trough and a plurality of airflow channels in communication with the opening, the vapor-phase working fluid in the first wick structure can rapidly flow through the opening and the airflow channels toward the cover plate, thereby conducting the heat generated by the heat-generating element to the cover plate rapidly.
Since the cover plate is formed with a plurality of supporting posts, and the second wick structure is provided between the cover plate and the bottom plate, the vapor-phase working fluid flowing toward the cover plate condenses on the cover plate, and then the condensed working fluid rapidly flows back to the first wick structure via the second wick structure and the supporting posts, thereby preventing the dry-out of the working fluid in the first wick structure and increasing the heat-conducting effect of the vapor chamber.
The bottom plate has an accommodating trough. The cover plate is formed with a plurality of supporting posts at a position corresponding to the accommodating trough. The supporting posts are configured to connect and support between the cover plate and the first wick structure. Thus, the supporting posts serve as a path for allowing the vapor-phase working fluid to flow back to the first wick structure. Further, the supporting posts provide a sufficient strength between the cover plate and the first wick structure, thereby preventing the cover plate from recessing into the accommodating trough.
The detailed description and technical contents of the present invention will become apparent with the following detailed description accompanied with related drawings. It is noteworthy to point out that the drawings is provided for the illustration purpose only, but not intended for limiting the scope of the present invention.
Please refer to
The bottom plate 10 is made of metallic material. One side of the bottom plate 10 has a heated protrusion 11 brought into thermal contact with the heat-generating element 100 (as shown in
The first wick structure 20 is provided in the accommodating trough 12. The first wick structure 20 is shaped as a plate to be flatly disposed in the bottom of the accommodating trough 12. By this arrangement, the heat generated by the heat-generating element 100 can be conducted to the accommodating trough 12 via the heated protrusion 11 of the bottom plate 10 and absorbed by the working fluid 50 in the first wick structure 20. The first wick structure 20 is an element made of sintered metal powder or metal woven mesh. However, the first wick structure 20 made of sintered metal power has a larger density.
The periphery of one surface of the bottom plate 10 on the same side as the accommodating trough 12 is formed with a flange 13. The thickness of the flange 13 is substantially the same as the thickness of the second wick structure 30, so that the second wick structure 30 can be flatly disposed on the bottom plate 10. The second wick structure 20 is made of metal woven mesh. The second wick structure 30 has an opening 31 corresponding to the accommodating trough 12 and a plurality of airflow channels 32 in communication with the opening 31. More specifically, the second wick structure 30 is shaped as a plate to be adhered to the bottom plate 10. The center of the second wick structure 30 is provided with an opening 31 corresponding to the accommodating trough 12. The periphery of the opening 31 is arranged with a plurality of wick pieces 33. An airflow channel 32 is formed between any two adjacent wick pieces 33. Thus, the airflow channels 32 are arranged to surround the opening 31. Similarly, the airflow channels 32 may be cross-linked to form cross-shaped channels as shown in
It should be noted that, the distal end of each wick piece 33 adjacent to the opening 31 is bent into a guiding section 331 toward the first wick structure 20. By this arrangement, the condensed working fluid 50 can rapidly flow into the first wick structure 20 in the accommodating trough 12 via the wick pieces 33 of the second wick structure 30 along the guiding sections 331, thereby preventing the dry-out of the working fluid 50 in the first wick structure 20.
The cover plate 40 is made of metallic materials and tightly covers the bottom plate 10. The profile of the cover plate 40 corresponds to the profile of the bottom plate 10. In this way, between the cover plate 40 and the bottom plate 10, a sealing space is generated, in which the liquid/vapor phase change and circulation of the working fluid 50 occur. The cover plate 40 is formed with a plurality of supporting posts 41 at positions corresponding to the accommodating trough 12. The supporting posts 41 may be made of sintered metal powder, metallic posts (as shown in
The working fluid 50 is filled between the cover plate 40 and the bottom plate 10. The liquid-phase working fluid 50 is naturally collected in the accommodating trough 12 and enters the first wick structure 20 due to gravity force.
Please refer to
Please refer to
The vapor chamber 1 of the present embodiment also includes the bottom plate 10, the first wick structure 20, the second wick structure 30, the cover plate 40, the supporting posts 41 and the working fluid 50. The same description of the present embodiment as that of the previous embodiment is omitted for simplicity.
As shown in
The first wick structure 20 is disposed in the accommodating trough 12 on the opposite side of the first heated protrusion 11. The cover plate 40 is formed with supporting posts 41 corresponding to the first wick structure 20. The first wick structure 20′ is disposed in the accommodating trough 12′ on the opposite side of the second heated protrusion 11′. The cover plate 40 is formed with supporting posts 41′ corresponding to the first wick structure 20′. The second wick structure 30 is formed with two openings (as shown in
Please refer to
Similarly, the second heated protrusion 11′ is brought into thermal contact with the second heat-generating element 120 to absorb the heat generated by the second heat-generating element 120. The heat absorbed by the second heated protrusion 11′ is conducted through the bottom plate 10 to enter the accommodating trough 12′, so that the working fluid 50′ in the first wick structure 20′ disposed in the accommodating trough 12′ evaporates and flows to the cover plate 40 along the airflow channels 32. The cover plate 40 is connected to a heat-dissipating fin set 200 for dissipating the heat in the cover plate 40 to the outside. After releasing the latent heat, the working fluid 50′ condenses and flows back to the first wick structure 20′ along the second wick structure 30 (as shown in
In this way, the vapor chamber 1 rapidly conducts the heat generated by the first heat-generating element 110 and the second heat-generating element 120 to heat-dissipating fin set 200, thereby dissipating the heat to the outside.
Although the present invention has been described with reference to the foregoing preferred embodiments, it will be understood that the invention is not limited to the details thereof. Various equivalent variations and modifications can still occur to those skilled in this art in view of the teachings of the present invention. Thus, all such variations and equivalent modifications are also embraced within the scope of the invention as defined in the appended claims.
