Patent Description:
A circuit board with complex functions, for example, a graphics card and a motherboard, usually have a plurality of chips that easily generate heat. Taking the motherboard an example, besides a CPU with a high thermal power, chips such as power chips, on-board memory chips, on-board graphics chips, and the like with high thermal power may be disposed around the CPU. Since heights of these chips are different, it is necessary to dispose a plurality of heat sinks to contact the chips of different heights, to dissipate heat for different chips.

When the chips are densely arranged, the adjacent space between the chips is reduced accordingly. In this case, fixing structures between different heat sinks are likely to interfere with each other, which cause the heat sinks to be redesigned according to the arrangement of the chips. In addition, plural heat sinks arranged densely cause the assembly procedure to become complicated and affect the assembly efficiency. Each of <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT> discloses a heat dissipation device, comprising: a heat conductor, including a heat dissipation side and a heat absorption side opposite to each other; wherein the heat absorption side is formed by at least two contact planes; wherein the heat dissipation device is characterized in that the at least two contact planes are arranged in parallel to each other, and a height difference exists between the at least two contact planes. <CIT>, and <CIT> disclose some further designs.

According to the present invention, a heat dissipation device as defined by claim <NUM> is provided. The dependent claims show some examples thereof. In view of the above problems, this disclosure provides a heat dissipation device for simultaneously satisfying heat dissipation requirements of a plurality of heating elements.

This disclosure proposes a heat dissipation device, including a heat conductor. The heat conductor includes a heat dissipation side and a heat absorption side opposite to each other. The heat absorption side is formed by at least two contact planes, the at least two contact planes are arranged in parallel to each other, and a height difference exists between the at least two contact planes.

In at least one embodiment, the heat dissipation device further includes a plurality of heat-conducting medium respectively disposed on one of the at least two contact planes, and the plurality of heat-conducting medium are deformable.

In at least one embodiment, the heat dissipation device further includes a heat dissipation structure disposed on the heat dissipation side.

In at least one embodiment, the heat dissipation structure is a water cooled heat sink, a plurality of heat dissipation fins, or a heat pipe.

In at least one embodiment, the heat dissipation device further includes a heat pipe with one end of the heat pipe disposed in the heat conductor.

According to the present invention, the at least two contact planes are capable to move relative to each other, to change the height difference.

According to the present invention, the heat conductor includes at least two blocks, the at least two blocks respectively correspond to one of the at least two contact planes, and the at least two blocks are connected through a sliding guide structure, so as to move relative to each other to change the height difference.

In at least one embodiment, the at least two blocks are respectively a water cooled heat sink and the at least two blocks are connected by at least a pipeline.

According to the present invention, the heat dissipation device further includes a heat-conducting member having two ends respectively connected to the at least two blocks.

In at least one embodiment, the heat dissipation device further includes at least two bumps respectively disposed on the at least two contact planes, and at least one of the at least two bumps is detachable.

In at least one embodiment, one of the at least two contact planes includes a positioning dent configured to position the bump which is detachable.

In at least one embodiment, the heat dissipation device further includes a plurality of fixing members passing through the heat conductor.

In at least one embodiment, the heat dissipation device further includes a back plate and a plurality of fixing members, wherein the back plate is connected to the heat absorption side through the plurality of fixing members, and the back plate is spaced apart from the heat absorption side.

The heat sink of this disclosure has a plurality of contact planes of different heights, and may be respectively in contact with heating elements of different heights. Therefore, the heat sink of this disclosure can easily achieve the effect of heat dissipation by a plurality of heating elements at the same time. In at least one embodiment, according to this disclosure, through different structural changes, a first height difference between the contact planes and a second height difference between the heating elements are compensated, further solving the problem that the first height difference and the second height difference cannot be matched due to manufacturing tolerances or heating elements being replaced with heating elements of different specifications.

This disclosure will become more fully understood from the detailed description given herein below for illustration only, and thus not limitative of this disclosure, wherein:.

Referring to <FIG> and <FIG>, a heat dissipation device <NUM> disclosed in a first example of this disclosure is shown, which is suitable for a circuit board <NUM> having a plurality of heating elements HS1, HS2. The plurality of heating elements HS1, HS2 have at least two different heights on the circuit board <NUM>.

As shown in <FIG> and <FIG>, the heat dissipation device <NUM> includes a heat conductor <NUM>. The heat conductor <NUM> is made of a material with good thermal conductivity. The heat conductor <NUM> is usually made of metal such as copper or aluminum, and other non-metallic materials with high thermal conductivity are not excluded.

As shown in <FIG>, <FIG>, and <FIG>, the heat conductor <NUM> has a heat dissipation side 110a and a heat absorption side 110b. The heat absorption side 110b is formed by at least two contact planes S1, S2, the at least two contact planes S1, S2 are arranged in parallel to each other. A first height difference D1 exists between the at least two contact planes S1, S2. As shown in <FIG>, the plurality of heating elements HS1, HS2 have two different heights on the circuit board <NUM>. In one specific example, one of the heating elements HS1, HS2 is a central processing unit (CPU), and the remaining heating elements HS1, HS2 are memory chip modules. The memory chip module is fixed onto the circuit board <NUM> by surface mounting or other welding techniques. The CPU and the memory chip module have different heights on the circuit board <NUM>, and there is a second height difference D2.

As shown in <FIG>, the first height difference D1 and the second height difference D2 are similar and preferably the same. The heat absorption side 110b is respectively in contact with the heating elements HS1, HS2 of different heights with different contact planes S1, S2, so that the heat absorption side 110b can make surface contact with the heating elements HS1, HS2 of different heights at the same time, and absorb heat generated by the plurality of heating elements HS1, HS2 during operation. Generally, the same type of heating elements HS1, HS2 are concentrated in the same area for configuration. For example, after the CPU is separately arranged, a plurality of memory chip modules are concentrated in an area adjacent to the CPU for arrangement. Therefore, a single one of the contact planes S1, S2 may be in contact with a plurality of heating elements HS1, HS2 with the same height (for example, memory chip modules) at the same time, which is not limited to a single one of the contact planes S1, S2 in contact with a single one of the heating elements HS1, HS2.

As shown in <FIG>, in order to solve the tolerance problem, that is, when differences exist between the first height difference D1 and the second height difference D2 and different, the heat dissipation device <NUM> further includes a plurality of heat-conducting mediums TM1, TM2. The heat-conducting mediums are respectively disposed on one of a plurality of contact planes S1, S2, so that each of the contact planes S1, S2 is in indirect contact with the heating elements HS1, HS2 through the heat-conducting medium TM1, TM2. The heat-conducting medium TM1, TM2 are deformable, for example, the heat-conducting mediums TM1, TM2 may be heat-conducting foam tapes or a heat-conducting paste. The deformable heat-conducting medium TM1, TM2 are capable to be pressed to change the thickness, to compensate the difference between the first height difference D1 and the second height difference D2, so that the plurality of contact planes S1, S2 can be reliably in contact with the heating elements HS1, HS2.

As shown in <FIG>, <FIG>, <FIG>, the heat conductor <NUM> further includes a plurality of fixing through holes <NUM> penetrating the heat dissipation side 110a and the heat absorption side 110b. The fixing through hole <NUM> is preferably arranged near an edge of the heat conductor <NUM>, so that the fixing through hole <NUM> can be in communication with different contact planes S1, S2 on the heat absorption side 110b. The heat dissipation device <NUM> further includes a plurality of fixing members <NUM> configured to pass through the heat conductor <NUM>. The plurality of fixing members <NUM> pass through the fixing holes <NUM> and are fixed onto the circuit board <NUM>, to fix the heat conductor <NUM> of the heat dissipation device <NUM> to the circuit board <NUM>, and cause the heat conductor <NUM> to press the heating elements HS1, HS2 appropriately, thereby strengthening the contact between the contact planes S1, S2 and the heating elements HS1, HS2.

The above fixing member <NUM> may be directly fixed to the circuit board <NUM> through screw locking, or may be indirectly fixed to the circuit board <NUM> through the combination of other elements.

As shown in <FIG>, and <FIG>, a heat dissipation structure <NUM> may be selectively disposed on the heat dissipation side 110a for cooling the heat conductor <NUM>.

As shown in <FIG>, the heat dissipation structure <NUM> may be a plurality of heat dissipation fins to cool the heat conductor <NUM> by air cooling. In addition to natural convection air cooling, the heat dissipation device <NUM> may further include a fan <NUM> fixed onto the heat dissipation fins, to cool the heat conductor <NUM> by forced air cooling.

As shown in <FIG>, the heat dissipation structure <NUM> may be an external water cooled heat sink. The water cooled heat sink is fixed onto the heat dissipation side 110a. The water cooled heat sink has a cooling passage <NUM>, and the cooling passage <NUM> is connected to a pump through a pipeline, to pump cooling water or other coolant liquid to circulate in the cooling passage <NUM>, to cool the heat conductor <NUM>.

As shown in <FIG>, the heat conductor <NUM> may be directly configured to be a water cooled heat sink, and is connected to the pump by using the cooling passage <NUM> through a pipeline.

As shown in <FIG>, the heat dissipation structure <NUM> may be a heat pipe, one end of the heat pipe is disposed on the heat dissipation side 110a or in the heat conductor <NUM>, and the other end of the heat pipe is connected to a cooling unit (such as a fin assembly).

As shown in <FIG>, <FIG>, a heat dissipation device <NUM> disclosed in a second embodiment of this disclosure is shown. In the second embodiment, at least two contact planes S1, S2 are configured to be capable to move relative to each other, to change the first height difference D1, so that the first height difference D1 is capable to match the change of the second height difference D2. The change of the second height difference D2 may be derived from the dimensional tolerance between the heating elements HS1, HS2, or may be derived from the replacement of the heating elements HS1, HS2 with heating elements HS1, HS2 of different dimensions.

As shown in <FIG>, <FIG>, in the second embodiment, the heat conductor <NUM> includes at least two blocks <NUM>, and the at least two blocks <NUM> respectively correspond to a contact plane S1, S2. The at least two blocks <NUM> are connected through a sliding guide structure <NUM>, and the at least two blocks <NUM> can move relative to each other, causing the at least two contact planes S1, S2 to move relative to each other to change the first height difference D1, so that the first height difference D1 is capable to match the second height difference D2.

As shown in <FIG>, <FIG>, the at least two blocks <NUM> respectively have a joint surface 118a, two joint surfaces 118a are configured to be in contact with each other, and the joint surface 118a is approximately perpendicular to the contact planes S1, S2. The sliding guide structure <NUM> is a combination of a guide groove 119a and a guide rail 119b, and the guide groove 119a and the guide rail 119b are respectively disposed on two joint surfaces 118a. The directions in which the guide groove 119a and the guide rail 119b extend are perpendicular to the contact planes S1, S2. The guide rail 119b is slidably disposed in the guide groove 119a, so that the two joint surfaces 118a are at least partially in contact with each other, and the guide rail 119b and the guide groove 119a guide the two blocks <NUM> to move relative to each other, to change the first height difference D1.

As shown in <FIG>, the heat dissipation device <NUM> of the second embodiment is also fixed by using a plurality of fixing members <NUM>, and each of the blocks <NUM> is provided with a fixing through hole <NUM> for the fixing members <NUM> to pass through. The heat dissipation device <NUM> may further include a back plate <NUM>. The back plate <NUM> is connected to the heat absorption side 110b through the plurality of fixing members <NUM>, and back plate <NUM> is spaced apart from the heat absorption side 110b. The circuit board <NUM> and the heating elements HS1, HS2 are located between the back plate <NUM> and the heat absorption side 110b, so that the contact planes S1, S2 are pressed against the heating elements HS1, HS2 by clamping. In addition, the back plate <NUM> may be configured to reinforce the circuit board <NUM>, to avoid bending and deformation of the circuit board <NUM>.

As shown in <FIG>, the at least two blocks <NUM> may be two water cooled heat sinks, that is, each of the blocks <NUM> has a cooling passage <NUM> therein. The cooling passage <NUM> between the at least two blocks <NUM> is connected to a pump by using at least one pipeline <NUM>, so that the cooling liquid can circulate in the two blocks <NUM>.

As shown in <FIG>, in order to enhance the thermal equilibrium between the two blocks <NUM> and avoid the overheating of the corresponding block <NUM> caused by the excessive thermal power of the individual heating elements HS1, HS2, the heat dissipation device <NUM> further includes a heat-conducting member <NUM>, for example, a heat pipe or a metal strip. Two ends of the heat-conducting member <NUM> are respectively connected to the two blocks <NUM>, to transfer heat between the two blocks <NUM>. The heat-conducting member <NUM> may be deformed appropriately to match the movement between the two blocks <NUM> relative to each other.

As shown in <FIG>, a heat dissipation device <NUM> disclosed in a third embodiment of this disclosure is shown. The heat dissipation device <NUM> of the third embodiment further includes two bumps <NUM>. The two bumps <NUM> are respectively disposed on two contact planes S1, S2. At least one of the two bumps <NUM> is detachable. One of the at least two contact planes S1, S2 includes a positioning dent P configured to receive and position the detachable bump <NUM>. The two bumps <NUM> are configured to be in contact with the heating elements HS1, HS2, so that the contact planes S1, S2 are indirectly connected to the heating elements HS1, HS2.

As shown in <FIG>, a compensation height difference D3 is formed between the two bumps <NUM>, and the compensation height difference D3 matches a second height difference D2 between the heating elements HS1, HS2. When the heating elements HS1, HS2 on the circuit board <NUM> change, and the second height difference D2 changes, the detachable bump <NUM> can be replaced by another detachable bump <NUM> to change the compensation height difference D3, so that a new compensation height difference D3' between the two bumps <NUM> can match the changed second height difference D2.

Claim 1:
A heat dissipation device (<NUM>) for an electronic device, comprising:
a heat conductor (<NUM>), including a heat dissipation side (110a) and a heat absorption side (110b) opposite to each other; wherein the heat absorption side (110b) is formed by at least two contact planes (S1, S2);
wherein the at least two contact planes (S1, S2) are arranged in parallel to each other, and a height difference (D1 or D2) exists between the at least two contact planes (S1, S2);
wherein the at least two contact planes (S1, S2) are configured to move relative to each other, so as to change the height difference (D1 or D2), the heat conductor (<NUM>) comprises at least two blocks (<NUM>), the at least two blocks (<NUM>) respectively correspond to a respective one of the at least two contact planes (S1, S2), and two of the at least two blocks (<NUM>) are connected through a sliding guide structure (<NUM>), so as to move relative to each other to change the height difference (D1 or D2);
wherein said two of the at least two blocks (<NUM>) respectively include a joint surface (118a), the two joint surfaces (118a) are in contact with each other, the sliding guide structure (<NUM>) is a combination of a guide groove (119a) and a guide rail (119b), the guide groove (119a) and the guide rail (119b) are respectively disposed on the joint surfaces (118a) of said two of the at least two blocks (<NUM>), and directions in which the guide groove (119a) and the guide rail (119b) extend are perpendicular to the at least two contact planes (S1, S2);
wherein the heat-dissipation device further comprises a heat-conducting member (<NUM>) which has two ends respectively connected to said two of the at least two blocks (<NUM>) and the heat-conducting member (<NUM>) is deformable to match the movement between said two of the at least two blocks relative to each other.