WO2016122601A1

WO2016122601A1 - Fan and fin assembly

Info

Publication number: WO2016122601A1
Application number: PCT/US2015/013792
Authority: WO
Inventors: Robert L. Crane
Original assignee: Hewlett-Packard Development Company, L.P.
Priority date: 2015-01-30
Filing date: 2015-01-30
Publication date: 2016-08-04

Abstract

A fan has an exhaust surface or edge from which air is expelled. A fin assembly has fins extending from the exhaust surface or edge of the fan. Air expelled from the fan is guided between the fins. The fins are of differing lengths, from a shortest fin towards a first end of the exhaust surface or edge to a longest fin towards a second, opposite end of the exhaust surface or edge.

Description

FAN AND FIN ASSEMBLY

BACKGROUND

[0001] Electronic devices, such as laptop and notebook computers generally include heat-generating components. Examples of such heat- generating components include integrated circuits (ICs), such as processors like central processor units (CPUs) and graphical processor units (GPUs). To prevent heat from excessively building up within the housings or enclosures of electronic devices within which these heat-generating components are located, the devices can include one or more fans, or blowers, to expel the heat outside their housings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0002] FIG. 1 is a diagram of a top view of an example electronic device including a fan and a fin assembly.

[0003] FIG. 2 is a diagram of a back view of the example electronic device of FIG. 1 .

[0004] FIG. 3 is a diagram of a cross-sectional side view of the example electronic device of FIG. 1 .

[0005] FIG. 4 is a flowchart of an example method for assembling an example electronic device including a fan and a fin assembly. DETAILED DESCRIPTION

[0006] As noted in the background, electronic devices can include fans to expel heat. If the heat were not removed from the devices, the internal temperature can become too high, adversely affecting heat-sensitive

components of the devices, which may be the same components that generate the heat. For example, integrated circuits (ICs) may have an upper temperature limit past which they may perform improperly or even fail.

[0007] The real estate within the enclosure of an electronic device such as a laptop or notebook computer is, however, a scarce commodity. Therefore, fans may have to be located within such a device at places and at orientations where there is available space, regardless of whether these locations and orientations are most optimal for removing heat from the device. Furthermore, fans may have to be located and oriented to ensure that they do not interfere with other components of the device, such as the mechanical hinge of a laptop computer by which the upper half of the computer is opened and closed relative to the computer's lower half.

[0008] In one configuration of a laptop or notebook computer, for example, the fan is rotated relative to, and located away from, the edge of the computer's case at which air is exhausted from the computer. A rectangular heat sink in the form of a fin stack having a series of equal length heat-absorbing fins is attached at one end adjacent to this edge. The fan has an enclosing or flow-directing shroud that is longer on one side than another, so that the edge of the fan at which air is exhausted is still parallel to the edge of the computer's case to which the fin stack is attached. This edge of the fan is thus attached to the opposite edge of the fin stack. In this way, the fan expels air from inside the case through the series of fins of the fin stack and outside the case.

[0009] Disclosed herein are fan and fin assemblies that improve on these existing configurations. In particular, for a fan that is rotated relative to the edge of a computer's case at which air is exhausted from the computer, the edge of the fan at which air is expelled from the fan is non-parallel to this edge of the case. Instead, the fin stack is non-rectangular so that the fan still expels air through the series of fans of the fin stack, and so that opposite ends of the stack are still adjacent to the aforementioned (non-parallel) edges of the case and the fan. The fin stack may be trapezoidal or triangular in shape, for example.

[0010] Such a fan and fin assembly provides for certain technological advantages. For example, because the fins at one side of the non-rectangular fin stack are shorter than the fins at the opposite side of the stack, air has paths of varying length along which to travel before exiting the computer's case. By comparison, in a rectangular fin stack, air has paths of equal length to travel along before existing the case. The varying length paths can provide for different frequencies of noise being generated by the airflow, resulting in perceptively less noise as compared to equal length paths.

[0011] As another example, where the shortest fin of the non-rectangular fin stack has a length equal to that of every fin of a corresponding rectangular fin stack, this means that the overall surface area provided by the fins is greater in the non-rectangular stack than in the rectangular stack. The heat absorbing capability of a fin stack generally increases with surface area. As such, the cooling effectiveness when employing a non-rectangular fin stack is improved. Increasing cooling capability also can reduce noise generation, since the fan may be able to operate at shorter periods of time and/or at lower speeds to achieve the same cooling effect.

[0012] FIG. 1 shows a top view of a portion of an example electronic device 100, such as a laptop or a notebook computer. The electronic device 100 includes a housing 102, which may also be referred to as an enclosure or a case. In the implementation where the device 100 is a laptop or notebook computer, for instance, the housing 102 may be the housing for the bottom half of the computer. The electronic device 100 includes a logic board 104 on which a fan 106 and a fin assembly 108 can be attached or disposed. The fan 106 can also be referred to as a blower, and the fin assembly 108 can also be referred to as a fin stack. The electronic device 100 can further include a heat-generating component 1 10 attached or disposed to the logic board 104, and a heat pipe 1 12. The device 100 can and typically does include other mechanisms and components in addition to those depicted in FIG. 1 . Furthermore, although just one fan 106 and one fin assembly 108 are depicted, there can be more than one fan 106 and one fin assembly 108.

[0013] The housing 102 has an edge 1 14, which also may be referred to as a surface, at which heated air is expelled outwards from the housing 102 of the electronic device 100, at the location 1 16 that may include an appropriate slot or other type of aperture. As such, the edge 1 14 is a housing exhaust or outlet edge. The logic board 104 is the board on which electronic and other

components of the electronic device 100 can be mounted to realize the

functionality of the device 100. The heat-generating component 1 10 may be one such component, such as a processor, for instance.

[0014] The fan 106 includes an impeller 1 18 that is rotated to move air within the housing 102 of the electronic device 100. The fan 106 includes a shroud 120 that guides the air moved by the impeller 1 18 to expel the air from the fan 106 at an edge 122 of the fan 106. As such, the edge 122 is a fan exhaust or outlet edge. The shroud 120 may also be referred to as an enclosure, and the edge 122 may also be referred to as a surface. The fan 106 is disposed relative to the housing 102 such that the edge 122 of the fan 106 is non-parallel to the edge 1 14 of the housing 102. For instance, where the shroud 120 has a symmetrical shape as in FIG. 1 , the fan 106 may be considered as having a rotated orientation relative to the housing 102.

[0015] The fin assembly 108 includes a number or series of fins 124 extending from the fan edge 122 to the housing edge 1 14. The fins 124 guide the air expelled from the fan 106 at the fan edge 122 outwards from the housing 102 at the housing edge 1 14. Stated another way, the fan 106 moves or forces heated air between or through the fins 124, where the air exits the electronic device 100 at the edge 1 14 of the housing 102. While there are six fins 124 depicted in the example of FIG. 1 , there can be more or fewer fins 124. The fins 124 are of varying or differing lengths, from a shortest fin 124A at one end of the fin assembly 108 to a longest fin 124N at the other end of the assembly 108. Stated another way, the shortest fin 124A is located towards or at the end of the fan edge 122 closest to the housing edge 1 14, and the longest fin 124N is located towards or at the end of the fan edge 122 farthest from the housing edge 1 14.

[0016] In the example of FIG. 1 , therefore, the fin assembly 108 is trapezoidal in shape. More generally, the fin assembly 108 is non-rectangular in shape. For example, if the fan 106 were located so that one end of the fan edge 122 touched the housing edge 1 14, the fin assembly 108 would be triangular in shape. More generally, then, the fin assembly 108 can be sized and positioned within the housing 102 so that the fins 124 each extend from adjacent to the fan edge 122 to adjacent to the housing edge 1 14.

[0017] The heat pipe 1 12 is attached at one end to the heat-generating component 1 10, and at another end to the fins 124 of the fin assembly 108. The fins 124 of the fin assembly 108, as well as the heat pipe 1 12, are generally made from a heat-absorbing material, such as a metallic material like copper. The fins 124 thus absorb heat from within the housing 102 that is expelled by the airflow generated by the fan 106. Similarly, the heat pipe 1 12 absorbs heat generated by the heat-generating component 1 10, which travels by convection to the fins 124, at which this heat is also expelled by the airflow generated by the fan 106.

[0018] FIG. 2 shows a back view of the electronic device 100 with respect to the arrow 126 in FIG. 1 , and FIG. 3 shows a cross-sectional side view of the electronic device 100 with respect to the cross-sectional line 128 in FIG. 1 . In FIG. 2, the housing edge 1 14 of the housing 102 is depicted, including the location 1 16 at which heated air exits the electronic device 100. Specifically, the housing edge 1 14 includes a slot 202 at the location 1 16 through which heated air leaves the device 100.

[0019] In FIG. 3, the housing edge 1 14 of the housing 102 is again shown, as are the logic board 104, the fan 106 and its fan edge 122, the shortest fin 124A of the fins 124 of the fin assembly 108, and the heat pipe 1 12. Also depicted in FIG. 3 is another heat-generating component 302 of the electronic device 100, which is different than the heat-generating component 1 10 of FIG. 1 . The fan 106 in example of FIG. 3 is positioned over the heat-generating component 302, at one of two fan intake or inlet edges 304 of the fan 106. The fan 106 draws air at the intake edges 304 and expels the air at the fan edge 1 12. There may just be one fan intake edge 304 in another implementation. The example of FIG. 3 thus shows how the fan 106 may be positioned to provide extra cooling capability in relation to a particular heat-generating component 302 of the electronic device 100.

[0020] FIG. 4 shows an example method 400 for assembling the electronic device 100. The method 400 includes disposing the logic board 104 within the housing 102 of the electronic device 100 (402). The logic board includes at least the heat-generating component 1 10, and can also include the heat-generating component 302. The method 400 includes disposing the fan 106 within the housing 102 in such a way that the fan exhaust edge 122 is non-parallel to the housing exhaust edge 1 14 (404). In an implementation in which the logic board 104 includes the heat-generating component 302, the fan 106 may be disposed within the housing 102 so that one of the fan intake edges 304 is positioned over the heat-generating component 302. The method 400 includes disposing the fin assembly 108 within the housing 102 between the edges 1 14 and 122 and adjacent to each edge 1 14 and 122 (406). In one implementation, the fin assembly 108 may be disposed within the housing 102 prior to the fan 106. The method includes attaching one end of the heat pipe 1 12 to the heat-generating component 302, and the other end of the heat pipe 1 12 to the fin assembly 108.

Claims

We claim:

1 . An electronic device comprising:

a fan having a fan exhaust edge from which air is expelled;

an enclosure in which the fan is disposed and having an enclosure exhaust edge non-parallel to the fan exhaust edge; and

a fin assembly having a plurality of fans extending from the fan exhaust edge to the enclosure exhaust edge to guide the air expelled from the fan outwards from the enclosure at the enclosure exhaust edge.

2. The electronic device of claim 1 , wherein the fins are of differing lengths, from a shortest fin towards an end of the fan exhaust edge closest to the enclosure exhaust edge to a longest fin towards an opposite end of the fan exhaust edge farthest from the enclosure exhaust edge.

3. The electronic device of claim 1 , wherein the fin assembly is non- rectangular in shape.

4. The electronic device of claim 1 , wherein the fin assembly is trapezoidal in shape.

5. The electronic device of claim 1 , further comprising a heat pipe mounted to the fin assembly, the air guided by the fins expelling heat absorbed by the heat pipe within the enclosure.

6. The electronic device of claim 5, further comprising a heat-generating electronic component to which the heat pipe is mounted.

7. The electronic device of claim 1 , further comprising a heat-generating electronic component over which a fan intake edge of the fan is positioned.

8. A cooling assembly comprising:

a fan having an exhaust surface from which air is expelled; and

a fin sub-assembly having a plurality of fins extending from the exhaust surface of the fan and between which the air expelled from the fan is guided, wherein the fins are of varying lengths, from a shortest fin towards a first end of the exhaust surface to a longest fin towards a second, opposite end of the exhaust surface.

9. The cooling assembly of claim 8, wherein the fan has an intake surface at which air is drawn into the fan, the intake surface substantially perpendicular to the exhaust surface and in contact with the exhaust surface.

10. The cooling assembly of claim 8, wherein the fin sub-assembly is non- rectangular in shape.

1 1 . The cooling assembly of claim 8, wherein the fin sub-assembly is trapezoidal in shape.

12. A method comprising:

disposing a blower within a housing for an electronic device such that a blower outlet surface of the blower is non-parallel to a housing outlet surface of the housing; and

disposing a fin stack within the housing between the blower outlet surface and the housing outlet surface,

wherein the fin stack has a plurality of fins of differing lengths, from a shortest fin towards an end of the blower outlet surface closest to the housing outlet surface to a longest fin towards an opposite end of the blower outlet surface farthest from the housing outlet surface.

13. The method of claim 12, further comprising:

disposing a logic board including a heat-generating electronic component within the housing.

14. The method of claim 13, further comprising:

attaching a first end of a heat pipe to the fin stack; and

attaching a second end of a heat pipe to the heat-generating electronic component.

15. The method of claim 13, wherein disposing the blower within the housing comprises disposing the blower in relation to the heat-generating electronic component such that a blower inlet surface of the blower is positioned over the heat-generating electronic component.