Heat sink   

Abstract: The present disclosure pertains to a heat sink having a base, a heat exchanger being thermally coupled to a top surface of the base, a housing having a chamber formed therein and being placed over the base with the heat exchanger enclosed within the chamber, an inlet connected to the inlet chamber for directing heat transfer medium into the heat sink, and an outlet connected to the outlet chamber for discharging the heat transfer medium from the heat sink, wherein the heat exchanger has a plurality of plates and a plurality of spacers, thereby providing for a plurality of channels.

This application claims the benefit of priority to U.S. Provisional Application No. 61/519,866, filed on Jun. 1, 2011, which is incorporated herein by reference in its entirety.

Electronic devices generate a high concentration of heat. Increased computing speeds have resulted in a corresponding increase in the power density of the electronic devices. Existing heat sinks for heat sources such as microelectronics components have generally used air to directly remove heat from the heat source. However, air has a relatively low heat capacity. Such forced air cooling assemblies are suitable for removing heat from relatively low power heat sources. Heat dissipation devices employing high heat capacity liquid like water and water-glycol solutions are more particularly suited to remove heat from high power density heat sources. The cooling liquid used in these heat sinks removes heat from the heat source and then transfers heat to a remote location where the heat can be easily dissipated.

SUMMARY

The present disclosure pertains to a heat dissipation device having a base, a heat exchanger being thermally coupled to a top surface of the base, a housing having a chamber formed therein and being placed over the base with the heat exchanger enclosed within the chamber, an inlet connected to the inlet chamber for directing liquid into the heat sink, and an outlet connected to the outlet chamber for discharging the liquid from the heat sink, wherein the heat exchanger has a plurality of plates and a plurality of spacers, thereby providing for a plurality of channels.

One aspect of the disclosure is a heat dissipation device wherein the plates and spacers are alternatively superposed. One aspect of the disclosure is a heat dissipation device wherein the base and the plates are made of a thermally conductive material. One aspect of the disclosure is a heat dissipation device wherein the spacers are made of a thermally conductive material. One aspect of the disclosure is a heat dissipation device wherein the heat exchanger further has a core, the plates have a hole, and the spacers have a hole, wherein the holes of the plates and spacers receive the core. One aspect of the disclosure is a heat dissipation device wherein the core is made of a thermally conductive material. One aspect of the disclosure is a heat dissipation device wherein the plates are annular.

One aspect of the disclosure is a heat dissipation device wherein the chamber has an inlet chamber, outlet chamber, and heat exchanger chamber. One aspect of the disclosure is a heat dissipation device having a gasket and a slot for receiving the gasket. One aspect of the disclosure is a heat dissipation device having mounting brackets. One aspect of the disclosure is a heat dissipation device having a pump for circulating the flow of liquid to the heat sink.

With those and other objects, advantages and features on the invention that may become hereinafter apparent, the nature of the invention may be more clearly understood by reference to the following detailed description of the invention, the appended claims, and the drawings attached hereto.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated herein and form part of the specification, illustrate various embodiments of the present invention and together with the description, further serve to explain the principles of the invention and to enable a person skilled in the pertinent art to make and use the invention. In the drawings, like reference numbers indicate identical or functionally similar elements. A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:

FIG. 1 is a perspective view of a heat sink according to an exemplary embodiment.

FIG. 2 is a perspective view of a heat sink according to an exemplary embodiment.

FIG. 3 is a side view of a heat sink according to an exemplary embodiment.

FIG. 4 is an exploded view of a heat exchanger according to an exemplary embodiment.

FIG. 5 is a perspective view of a heat sink according to an exemplary embodiment.

FIG. 6 is a perspective view of a heat sink according to an exemplary embodiment.

DETAILED DESCRIPTION

In the following detailed description, reference is made to the accompanying drawings which form a part hereof and in which is shown by way of illustration specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural or logical changes may be made without departing from the scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.

A heat dissipation device or heat sink 100 can be incorporated into a heat dissipation system by way of example for cooling a heat source, for example, without limitation, an electronic device, hydraulic system, water heater, light emitting diode, laser, mold, solar collector, or the like. A pump moves a heat transfer medium, for example, without limitation, a liquid or gas, through a heat sink 100 to dissipate heat from the heat transfer medium. The liquid can be any liquid suitable for removing heat from a heat source, for example, without limitation, water, water-glycol solutions, or the like. The cooling system can have a fan and a radiator to further reduce the heat of the liquid.

In one embodiment, as shown in FIG. 1, the heat sink 100 has a base 200 having a top surface and a central axis A substantially normal thereto. While the base 200 can be any shape, the base 200 is preferably rectangular in shape with the central axis A disposed at the center of the base 200. The base 200 can have a contact surface for contacting the electronic device and absorbing heat produced thereby.

In one embodiment, a housing 300 is fastened to the base 200 by conventional fasteners for example, without limitation, bolts. As shown in FIG. 2, the housing 300 has a top wall 310 and a peripheral sidewall 320 extending from the perimeter of the top wall 310 between the bottom surface of the top wall 310 of the housing 300 and the top surface of the base 200. The top wall 310 and sidewall 320 define a chamber. The chamber preferably has a heat exchange chamber 410, an inlet chamber 420, and an outlet chamber 430. In one embodiment, the bottom surface 321 of the sidewall 320 has a slot 330 to receive a gasket 600. The gasket 600 ensures a tight seal of the chamber between the base 200 and the bottom surface 321 of the sidewall 320, thereby preventing heat transfer medium from passing between the base 200 and the sidewall 320.

As shown in FIGS. 3 and 4, a heat exchanger 500 can be received by the heat exchange chamber 410 of the housing 300 with a bottom surface of the heat exchanger 500 thermally coupled to a top surface of the base 200, a top surface 501 of the heat exchanger 500 in contact with a bottom surface of the top wall 310 of the housing 300, and a central axis A in a position substantially normal to the top surface of the base 200. The inner periphery of the sidewall 320 can be in spaced relationship with the outer edge 502 of the heat exchanger 500 so that heat transfer medium may circulate between the inner periphery of the sidewall 320 and the outer edge 502 of the heat exchanger 500. The bottom surface of the top wall 310 can be in spaced relationship with the top surface 501 of the heat exchanger 500 so that heat transfer medium may circulate between the bottom surface of the top wall 310 and the top surface 501 of the heat exchanger 500.

The heat exchanger 500 can be substantially cylinder-shaped and has a plurality of plates 510 and spacers 520. The heat exchanger 500 can be mechanically and/or thermally coupled to the base 200 thereby allowing conduction of heat from the base 200 to the heat exchanger 500. While the plates 510 are preferably annular, the plates 510 can be any shape, for example, without limitation, elliptical, rectangular, teardrop, or the like. While the surface of the plates 510 is preferably smooth, the surface of the plates 510 can have, for example, without limitation, an undulated or wave-like surface, or a rough or rigid surface. In one embodiment, the annular plates 510 and spacers 520 are coaxially superposed, where the radius of the annular plates 510 is greater than the radius of the spacers 520. In one embodiment, the annular plates 510 are in spaced relationship with the inner periphery of the sidewall 320 allowing heat transfer medium to circulate between the inner periphery of the sidewall 320 and the annular plates 510. In one embodiment, as shown in FIGS. 3 and 4, the annular plates 510 and spacers 520 are alternatively superposed thereby defining channels 540 between the annular plates 510, thereby increasing the heat dissipation rate without increasing the footprint size of the heat exchanger 500. For example, a first annular plate 510 is stacked on the base 200, a spacer 520 is stacked on the first annular plate 510, a second annular plate 510 is stacked on the spacer 520, and so forth until all the annular plates 510 and spacers 520 are alternatively superposed. In one embodiment, the annular plates 510, spacers 520, and channels 540 run in a horizontal plane substantially normal to the central axis A. The channels 540 allow for the heat transfer medium to travel around the annular plates 510, spacers 520, and base 200 thereby removing heat from the annular plates 510, spacers 520, and base 200.

The inlet chamber 420 and the outlet chamber 430 are in heat transfer medium communication with each other through the heat exchange chamber 410 and the channels 540 formed within the heat exchanger 500.

In one embodiment, the heat exchanger 500 has a core 530 that can be mechanically and/or thermally coupled to the base 200 thereby allowing for the conduction of heat from the base 200 to the core 530. As shown in FIG. 4, the base can have a hole 220 for receiving the core 530 so that the bottom surface of the core 530 substantially lies in the same plane as the bottom surface of the base 200. As shown in FIGS. 3 and 5, the plates 510 and spacers 520 can be mechanically and/or thermally coupled to the core 530 thereby allowing for the conduction of heat from the core 530 to the plates 510 and spacers 520. As shown in FIG. 4, the annular plates 510 and spacers 520 can have a hole 511 for receiving the core 530. The annular plates 510 can be flattened between the spacers 520 when pressed onto the core 530, thereby preventing the annular plates 510 from becoming damaged when pressed onto the core 530 and allowing for the annular plates 510 to have a thin thickness. In one embodiment, the annular plate 510 has a thickness of 0.4 mm and the spacer 520 has a thickness of 0.4 mm. The annular plates 510 and spacers 520 are mechanically and thermally coupled to the core 530 thereby allowing for the conduction of heat from the core 530 to the annular plates 510 and spacers 520.

An inlet 700 can be disposed in the housing 300 for directing the heat transfer medium to the inlet chamber 420 and to the heat exchanger 500. An outlet 800 can be disposed in the housing 300 of the heat sink 100 for discharging the heat transfer medium. The inlet 700 and/or outlet 800 can be disposed on the top wall 310 of the housing 300 or the sidewall 320 of the housing 300. The heat transfer medium flows through the inlet 700, into the inlet chamber 420, through the channels 540 in the heat exchanger 500, into the outlet chamber 430, and through the outlet 800 where the heat transfer medium exits the heat sink 100. In one embodiment, the heat transfer medium flows substantially normal to the heat exchanger 500 to enhance heat dissipation from the heat exchanger 500. The inlet 700 and outlet 800 can have a compression fitting 710 for sealing the engagement of an inlet tube 720 to the inlet 700, and outlet tube 820 to the outlet 800, respectively, in a manner that prevents or reduces the heat transfer medium from flowing between the inlet tube 720 and the inlet 700 or the outlet tube 820 and the outlet 800.

Mounting brackets 900 engage the heat sink 100 and allow for the heat sink 100 to be secured in a manner that allows for the heat sink 100 to engage the heat source. In one embodiment, the mounting brackets 900 juxtapose the base 200 and the bottom surface 321 of the sidewall 320. The mounting brackets 900 can be secured to the heat source by conventional fasteners for example, without limitation, bolts.

During operation, heat generated by a heat source is first conducted to the base 200. The inlet tube 720 directs the heat transfer medium through the inlet 700 into the inlet chamber 420. The heat is transferred to the heat transfer medium as the heat transfer medium impinges the top surface of the base 200, annular plates 510, and spacers 520. The heat transfer medium flows through the channels 540 and into the outlet chamber 430 resulting in an upwelling of the heat transfer medium through the outlet 800. The heated heat transfer medium exits the heat sink 100 through the outlet 800 and, after being cooled, the heated heat transfer medium is returned to the heat sink 100 to perform another working cycle.

The base 200, heat exchanger 500, core 530, annular plates 510, and spacers 520 can be constructed of a thermally conductive material, such as copper, aluminum, silver, silver alloy, copper alloy, aluminum alloy, ferrous alloy, carbon based, ceramic or polymeric materials, or the like. However, any thermally conductive material suitable for absorbing and transferring heat may be utilized. Accordingly, the scope of the invention should not be limited to the type of material utilized for the base 200, heat exchanger 500, core 530, annular plates 510, or spacers 520.

The foregoing has described the principles, embodiments, and modes of operation of the present invention. However, the invention should not be construed as being limited to the particular embodiments described above, as they should be regarded as being illustrative and not as restrictive. It should be appreciated that variations may be made in those embodiments by those skilled in the art without departing from the scope of the present invention.

Modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that the invention may be practiced otherwise than as specifically described herein.