US20130020050A1

US20130020050A1 - Heat Sink Adaptor

Info

Publication number: US20130020050A1
Application number: US13/554,613
Authority: US
Inventors: Jonathan Robert Holman
Original assignee: Nidec Control Techniques Ltd
Current assignee: Nidec Control Techniques Ltd
Priority date: 2011-07-21
Filing date: 2012-07-20
Publication date: 2013-01-24
Also published as: CN102889817A; GB2493019A; GB201112598D0

Abstract

An adaptor is provided for use with the heat sink, said heat sink comprising a base for contacting a heat source and a plurality of protrusions extending from said base. The adaptor itself comprises a base and a structure projecting therefrom. The structure is arranged to mate with one or more protrusions on the heat sink to enable heat transfer by conduction from the heat sink to the adaptor.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of British Patent Application No. GB 1112598.6 filed on Jul. 21, 2011, the entire disclosure of which is incorporated herein by reference.

FIELD

The invention relates to an adaptor for a heat sink.

BACKGROUND

Heat sinks are well known devices that are used in a range of industries for cooling other devices that generate high temperatures. The term “heat sink” is generally used to describe any component or apparatus that transfers heat generated within a solid device to a fluid such as a liquid or air by convection. Heat sinks are used in refrigeration and air conditioning systems as well as for cooling a range of electronic and opto-electronic devices including computer central processing units (CPU's) and other processors.
FIG. 1 shows a typical heat sink 100. It comprises a base 102 and a series of fins 104 projecting outwardly therefrom. In the heat sink 100 shown in FIG. 1, the fins 104 project substantially perpendicularly from an upper face of the base 102. Each fin 104 is relatively thin so that a plurality of fins 104 can be arranged on the upper face of the base 102 with a gap between adjacent fins 104. Each fin 104 comprises first and second large substantially flat faces opposite one another. In FIG. 1 the large faces are substantially rectangular.
Other configurations of heat sink that differ from the one shown in FIG. 1 are well known. For example the fins in a heat sink may not project substantially perpendicularly from the base. They may instead project at different angles to create a flared or fanned fin arrangement. Alternatively or additionally, a plurality of pins may be used to replace the essentially planar fins shown in FIG. 1. In general, the purpose of the fins or pins in a heat sink is to create as large a surface area as possible within a given volume. That surface area is used for heat transfer from the heat sink to a surrounding fluid.
In operation, the base of a heat sink is placed in contact with a device that acts as a heat source and generates high temperatures, from which heat is to be directed away. The base can be placed in direct physical contact with the heat source. Optionally, a thermal adhesive or thermal grease may be added to the base of the heat sink to improve its thermal performance. Heat is conducted away from the heat source into the base and through the fins of the heat sink. That heat can then travel by convection from the heat sink to the surrounding fluid. The increased surface area of the fins aids transfer of heat to the surrounding fluid. Furthermore, the heat transfer by convection to the surrounding fluid can be enhanced by flow of the fluid around the heat sink, in particular in the gaps between the fins of the heat sink. Fluid can be forced between the fins of a heat sink, for example using a fan.
Whilst existing heat sinks are widely utilised and can be very useful in cooling heat generating devices, they are nonetheless limited to cooling by thermal convection. They are unable to operate in any other cooling mode without significant changes being made to their fundamental design. Cooling systems which include a heat sink are difficult to configure for use in different modes of operation without replacement of the heat sink. Therefore the range of suitable applications for conventional heat sinks is limited.
For example, conventional heat sinks are unsuitable for use in environments where the air used to provide ‘forced air cooling’ contain particulates (wood, stone, fibres etc.), as such particulates are likely to clog the fan circulating the air and the fins of the heat sink over time, reducing the efficiency of the heat sink. They also conventionally are unsuitable for use in environments where a high degree of protection is required from water, gas or dust as this necessitates installation of the heat sink in a sealed enclosure, limiting the supply of cool air to supply to the heat sink and thus reducing its efficiency.

SUMMARY

According to an aspect there is provided an adaptor for use with a heat sink, said heat sink comprising a base for contacting a heat source and a plurality of protrusions extending from said base. The adaptor itself comprises a base and a structure projecting from that base wherein the structure is arranged to mate with one or more protrusions on a heat sink to enable heat transfer by conduction from the heat sink to the adaptor. Preferably at least one surface of the structure on the adaptor can come into direct contact with a surface of a protrusion on the heat sink in order to enable the heat transfer by conduction from the heat sink to the adaptor. The structure may comprise projections, fins or pins extending from the base of the adaptor. Alternatively the structure may be substantially solid with recesses or channels therein into which protrusions on a heat sink can insert. The adaptor can channel heat which it collects from a heat sink to another location or cooling system by a range of different heat transfer means.
According to an aspect there is provided a cooling system for a heat source. The cooling system includes a heat sink comprising a base for contacting the heat source and channelling heat away therefrom as well as a plurality of protrusions extending from said base of the heat sink. The cooling system further comprises an adaptor comprising a base and a structure projecting from the base wherein the structure on the adaptor is arranged to mate with one or more of the protrusions on the heat sink to enable heat transfer by conduction from the heat sink to the adaptor.
According to another aspect there is provided a method of adapting a heat sink, said heat sink comprising a base for contacting a heat source and a plurality of protrusions extending from that base. The method comprises fitting an adaptor to the heat sink wherein that adaptor comprises a base and a structure projecting from said base. When the adaptor is fitted to the heat sink the structure on the adaptor is mated with one or more of the protrusions on the heat sink to enable heat transfer by conduction from the heat sink to the adaptor. Heat can then be channelled away from the adaptor using any suitable heat transfer technique.
According to another aspect there is provided a method of transferring heat away from a heat source. The method comprises putting a heat sink in contact with the heat source, said heat sink comprising a base for contacting the heat source and a plurality of protrusions extending from said base. The method further comprises fitting an adaptor to the heat sink wherein the adaptor comprises a base and a structure projecting from said base wherein fitting the adaptor to the heat sink includes mating the structure on the adaptor with one or more of the protrusions on the heat sink to enable heat transfer by conduction from the heat sink to the adaptor. Optionally the method may also comprise bringing the base of the adaptor, which is distal to the heat source when the heat sink is in contact therewith, into connection with an external component. That external component may be a cooling device.

FIGURES

Embodiments and examples will now be described with respect to the appended figures of which:

FIG. 1 shows an example of an existing finned heat sink;

FIG. 2 shows an example of a heat sink adaptor for use in conjunction with the heat sink of FIG. 1;

FIG. 3 shows the adaptor of FIG. 2 in connection with a heat sink; and

FIG. 4 shows a plan view of the adaptor of FIG. 2 in connection with a heat sink.

OVERVIEW

In overview there is provided an adaptor for use with a heat sink. In particular the adaptor can be used with a finned heat sink. The adaptor mates with the heat sink to enable heat transfer by conduction from the heat sink into the adaptor. Preferably at least one surface of the adaptor should directly contact a surface of the heat sink to enable such conduction. Increasing the size of the surface area over which the adaptor directly contacts the heat sink increases the extent of heat transfer therebetween. The adaptor has a structure which can include fins or other projections that insert into the gaps between protrusions such as fins on a heat sink so that heat can travel from those protrusions into the adaptor.
The physical configuration of the adaptor is largely dictated by the physical size and shape of the heat sink with which it is to be used. The adaptor must be able to mate with the heat sink and preferably it should be possible to lock the adaptor and heat sink together. At its distal end, away from the heat source which contacts the heat sink, the adaptor has a base. Preferably the outermost face of the base is substantially flat. Such an arrangement enables the adaptor to be connected to other external components such as other cooling devices. The adaptor may also comprise built-in cooling or heat transfer components such as liquid filled pipes.

DETAILED DESCRIPTION

The heat sink adaptor disclosed herein can be better understood with respect to the figures. As discussed above in the background section, FIG. 1 shows a typical existing finned heat sink 100. FIG. 2 shows such a heat sink aligned with an adaptor 200 for use therewith.
The adaptor 200 shown in FIG. 2 comprises a base 202 and a series of fins or other projections 204 extending therefrom. In the adaptor shown in FIG. 2 the projections 204 extend substantially perpendicularly from a face of the base 202. Each projection 204 is substantially rectangular in cross section and is relatively thin, with two large faces opposite one another, similar to the fins 104 described above with respect to the known heat sink 100. Because the adaptor 200 shown in FIG. 2 is for use with an existing finned heat sink such as the one shown in FIG. 1, the thickness of the projections 204 therein should ideally be sized to fit into the gaps between adjacent fins 104 in the heat sink 100. This can further be understood from FIGS. 3 and 4 which show the adaptor 200 in connection with the heat sink 100.
The adaptor 200 can include enough projections 204, appropriately sized and spaced, as to fit into every other gap between fins 104 in the heat sink 100, as shown in FIGS. 2 to 4. This ‘every other’ fin arrangement between the heat sink 100 and the adaptor 200 allows for the fins 104 of the heat sink 100 to move slightly as they receive the approaching projection 204 from the adaptor. Alternatively the adaptor 200 could have enough projections 204 as to fit into every gap between fins 104 in the heat sink 100 or only to fit into some of the gaps.
The projections 204 in one embodiment provide a friction fit between the adaptor 200 and a heat sink 100 to ensure good surface area contact. Any suitable configuration of the projections 204 could be implemented, provided sufficient surface area contact is ensured between the heat sink 100 and the adaptor 200 to allow the adaptor 200 to conduct enough heat from the heat sink 100 for a given situation.
The adaptor 200 can be aligned with the fins of a heat sink 100 as shown in FIG. 2 and inserted into the heat sink 100 as shown in FIGS. 3 and 4 to form a mating connection. The heat sink 100 and adaptor 200 combine to form a cooling system.
According to an embodiment, when the adaptor 200 is mated with the heat sink it will not occupy all of the gaps between the fins of the heat sink, so that there will still be some space for air or other fluid to flow through the cooling system. This allows the cooling system to cool at least partially using convection and so not rely entirely on conduction of heat from the heat sink 100 to the adaptor 200 in order to direct heat away from the heat sink 100.
The faces of the projections 204 on the adaptor 200 should fit as closely as possible to the respective fins 104 of the heat sink, via which heat is conducted out of the heat sink into the adaptor 200. The shape and orientation of the projections 204 on the adaptor 200 should also be matched as closely as possible with the shape and orientation of the fins 104 of the heat sink so that the adaptor 200 and heat sink can fit together easily and so that a large common surface area is provided for conduction of heat from the fins 104 of the heat sink to the projections 204 of the adaptor 200.
The adaptor 200 should be designed to provide as large a contact surface as possible for the heat sink with which it is to be used, to maximise heat transfer by conduction from the heat sink to the adaptor 200. For example, as shown in FIG. 4, the adaptor 200 shown in FIGS. 2 and 3 provides three contact surfaces for each fin 104 of the heat sink, via which heat can travel by conduction into the adaptor 200 out of the heat sink.
As shown in FIG. 3, the adaptor 200 can be fixed to the heat sink 100 by any suitable means such as bolts 206. The method of attachment should preferably be temporary, i.e. reversible, rather than permanent so that the adaptor 200 can be fitted to an existing heat sink when appropriate for certain applications and removed therefrom at other times without requiring any significant adaptation of either device. According to an embodiment, screws are used for fixing the adaptor 200 to the heat sink wherein the thread of the screw can form a thread in the walls of the fins of the heat sink during insertion.
In addition to the projections 204 described above, the adaptor 200 as shown in FIGS. 2 to 4 comprises a base 202. Each of the projections 204 terminates at the base 202 therefore the majority of the heat which is conducted into the adaptor 200 from the heat sink will be directed towards the base 202. As shown in FIG. 4, ideally the base 202 should have a substantially flat outer face, opposite the face from which the projections 204 extend. That substantially flat face can act as a flat surface for contact between the adaptor 200 and an external component such as a cooling device. Or another type of physical connection can be made between the adaptor 200 and the cooling device. For example that cooling device could be a water cooled heat sink, an air cooled plate or a “cold plate” cooling device. As is known in the art, such cooling devices cannot be used in direct contact with a conventional heat sink such as the one shown in FIG. 1 which transfers heat by convention to fluid only. However if an adaptor 200 such as the one shown in FIGS. 2 to 4 is used in conjunction with a conventional heat sink, intermediate the heat sink and the cooling device, those cooling devices (and other components) can be successfully used in conjunction with the conventional heat sink without having to permanently alter the design of either the heat sink or the cooling device itself. Therefore the adaptor increases the usefulness of the heat sink and the range of applications for which it can be used.
As well as being able to connect to external cooling devices for directing heat away therefrom, the adaptor 200 can include built in components to manage the removal of heat that the adaptor 200 collects from the heat sink. According to an embodiment, one or more pipes is embedded within the adaptor 200. The pipes can contain liquid or other fluid which can flow through the pipes out of the adaptor 200, thereby removing the heat therefrom. An arrangement of pipes within the adaptor 200 may also be part of a gas compression system to provide cooling due to fluid phase change. The energy requirements of a phase change from a liquid to a gas within the pipes efficiently draws heat away from the adaptor.
For situations where the product to be cooled must be contained within a sealed enclosure, the heat sink adaptor can provide a physical cooling ‘bridge’ to the outside of the enclosure where a greater supply of air, liquid or other cooling medium can be available.
The adaptor 200 may be fabricated from any suitable material or combination of materials. The material(s) should offer good thermal conductivity. For example the adaptor may comprise aluminium, copper, other ferrous or non-ferrous metals or glass.
The particular adaptor described above and shown in FIGS. 2 to 4 is a cold plate adaptor which is designed to fit with a finned heat sink as shown in FIG. 1 which has substantially rectangular fins extending generally at a right angle from a base of the heat sink. However other adaptors can be designed and can operate according to the same principles in conjunction with other designs of heat sink. For example if the heat sink has flared or irregularly angled fins projecting from its base, the size, shape and orientation of the projections of the adaptor can be appropriately configured to match the flared or irregularly angled fins, so that the projections fit well into the gaps between adjacent fins and have a large amount of surface area in common with the fins to provide thermal contact surfaces for conduction of heat from the heat sink to the adaptor. Similarly, if the heat sink comprises another type of protrusion, for example pins extending from the base, the adaptor can include suitably sized and shaped projections to match those protrusions. For example cylindrical projections, into which the pins of the heat sink can insert for conduction of heat from the heat sink to the adaptor, can be provided. Alternatively, the adaptor could comprise a substantially solid block with slots or channels therein into which the protrusions from the heat sink can insert.
As mentioned above, the base of the adaptor can be fitted to or can otherwise contact an external component such as another cooling device in any appropriate manner. For example, pipes or other conduits may be used to transfer heat from the adaptor 200 to an air cooled heat sink somewhere else, a water cooled system, a condensed gas system or any other suitable cooling device. As a result, a conventional heat sink (when used with the adaptor 200) can be more versatile. For example, instead of using forced air for cooling a conventional heat sink in environments where the air used contains particulates that are likely to clog the fins over time and thus reduce efficiency of the heat sink, the adaptor can be mated into the gaps between the fins of the heat sink and used to channel heat away from the heat sink, without needing to force particle-filled air around the heat sink. And in environments where a high degree of protection is required from water, gas or dust necessitating installation of the heat sink in a sealed enclosure, limiting the supply of cool air to supply to the heat sink and so reducing its efficiency, the adaptor can be used to remove heat from the heat sink using conduction instead of convection and channel it elsewhere without replacing the existing heat sink.
So it can be seen that the adaptor is highly useful for updating existing cooling systems which rely on conventional heat sinks and making them more useful and efficient without having to replace the heat sink. Therefore the adaptor is a cost effective solution which avoids physical disruption to existing systems. It can also be conveniently manufactured in conjunction with a new heat sink, hence increasing the heat sink's potential usefulness. The adaptor can include internal cooling components and/or can connect to external cooling components to direct heat away from the heat sink and associated heat source in any suitable manner, depending on the particular application or environment in which it is to be used. Therefore the adaptor enables an existing device which includes a heat sink to be used in a wider range of environments.
Whilst some specific examples of the uses of heat sinks have been given above, the adaptor described herein can be used in conjunction with a heat sink for any appropriate application in which heat must be transferred away from the heat source. The adaptor can be of any suitable size, shape and configuration in order cooperate with the heat sink physically and to meet the requirements for thermal transfer therefrom. The adaptor can be designed, manufactured and/or supplied with a co-operating heat sink, or can be retrofitted to an existing heat sink. By enabling heat to be conducted out of a conventional heat sink, rather than relying on convection, and by doing so in a simple and straightforward manner which does not require permanent adaptation of the existing heat sink, a highly useful and practical solution is provided by the adaptor.

Claims

1. An adaptor (200) for use with a heat sink, said heat sink comprising a base for contacting a heat source and a plurality of protrusions extending from said base, wherein said adaptor (200) comprises:

a base (202); and

a structure (204) projecting from said base (202);

wherein said structure (204) is arranged to mate with one or more protrusions on a heat sink to enable heat transfer by conduction from the heat sink to the adaptor (200).

2. An adaptor (200) as claimed in claim 1 wherein said structure (204) comprises a plurality of projections extending from said base (202) of the adaptor (200).

3. An adaptor (200) as claimed in claim 2 wherein said projections (204) comprise fins.

4. An adaptor (200) as claimed in claim 3 wherein said fins (204) are substantially rectangular in cross section.

5. An adaptor (200) as claimed in claim 2 wherein said projections (204) extend substantially perpendicularly from a face of said base (202).

6. An adaptor (200) as claimed in claim 2 wherein the projections (204) extend from a face of said base (202) in a flared arrangement.

7. An adaptor (200) as claimed in claim 1 wherein at least one surface of the structure (204) is arrange to contact at least one surface of the plurality of protrusions extending from the base of heat sink, to enable heat conduction from the heat sink to the adaptor (200).

8. An adaptor as claimed in claim 2 wherein at least one of said projections (204) is arranged to fit into a gap between adjacent protrusions on a heat sink, to provide a mating fit between the heat sink and the adaptor (200).

9. An adaptor (200) as claimed in claim 1 wherein said adaptor further comprises a built in cooling component.

10. An adaptor (200) as claimed in claim 9 wherein said built in cooling component comprises a fluid filled conduit.

11. An adaptor (200) as claimed in claim 1 wherein said base (202) is arranged to connect to an external cooling component for heat transfer from the adaptor (200) to said external cooling component.

12. A cooling system for a heat source, said cooling system including:

a heat sink (100) comprising a base (102) for contacting the heat source and a plurality of protrusions (104) extending from said base (102); and

an adaptor (200) as claimed in claim 1 in mating contact with said heat sink (100).

13. A method of adapting a heat sink (100), said heat sink (100) comprising a base (102) for contacting a heat source and a plurality of protrusions (104) extending from said base (102), wherein said method comprises fitting an adaptor (200) to the heat sink (100), said adaptor (200) comprising a base (202) and a structure (204) projecting from said base (202), wherein said fitting includes mating the structure (204) on the adaptor (200) with one or more protrusions (104) on the heat sink (100) to enable heat transfer by conduction from the heat sink (100) to the adaptor (200).

14. A method as claimed in claim 13 wherein the step of mating the structure (204) on the adaptor (200) with one or more protrusions (104) on the heat sink (100) comprises bringing at least one surface of the structure (204) into contact with at least one surface of the plurality of protrusions (104).

15. A method as claimed in claim 13 wherein the structure (204) on the adaptor (200) comprises a plurality of projections and wherein the step of mating said structure (204) with one or more protrusions (104) on the heat sink (100) comprises inserting at least one of said plurality of projections into a gap between adjacent protrusions (104) on the heat sink (100).

16. A method as claimed in claim 15 wherein said at least one projection (204) is sized and shaped so that, when it is inserted into said gap between adjacent protrusions (104) on the heat sink (100), an upper surface of the projection (204) comes into contact with the base of the heat sink (100).

17. A method as claimed in claim 15 wherein said at least one projection (204) is sized and shaped so that, when it is inserted into said gap between adjacent protrusions (104) on the heat sink (100), a side surface of the projection (204) comes into contact with a side surface of one of said adjacent protrusions (104) on the heat sink (100).

18. A method as claimed in claim 13 further comprising connecting said adaptor (204) to an external cooling component for transfer of heat from the adaptor (200) to said external cooling component.