JP2014179382A - Heat sink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce pressure loss of a heat sink while ensuring necessary cooling performance at a part where high cooling performance is necessary.SOLUTION: A heat sink comprises a heat sink body 1 having a base 11 on which heat generating elements 21 and 22 are mounted and a heat radiating portion 3 configured to include a plurality of fins 31 and a restricting section (duct 61) that restricts the flow direction of cooling air to a main stream direction. The heat sink body is divided into a first part where high cooling performance is necessary and a second part where cooling performance lower than that for the first part is permissible based on the thermal load and location of the heat generating body with respect to the main stream direction. The restricting section has an opposed wall surface that is disposed so as to face the base in a standing direction over the whole range of the main stream direction of the heat radiating portion. A first opposite wall surface (plate material 64) at a position corresponding to the first part is set to have a small gap from the base and a second opposite wall surface at a position corresponding to the second part is set to have a gap from the base which is wider than the gap of the first part.

Description

  The technology disclosed herein relates to a heat sink that cools a heating element.

  Patent Documents 1 and 2 describe a traveling wind heat sink. This heat sink is mounted on a railway vehicle and cools a heating element that is a power converter using cooling air as traveling air generated as the railway vehicle travels. Specifically, the heat sink has a plurality of fins attached to a base to which a heating element is attached, and heat is transmitted through each fin by cooling air flowing through slit-like channels formed between adjacent fins. Thus, the heat of the heating element is dissipated. Patent Document 3 describes a so-called forced air cooling heat sink in which a heat sink is arranged in a duct and cooling air from a blower is supplied to the heat sink through the duct.

JP 2007-134471 A International Publication No. 2010/109799 Japanese Patent Laid-Open No. 11-354694

  By the way, in the heat sink as described in Patent Documents 1 and 2, a plurality of heating elements are arranged side by side in the main flow direction of the cooling air (that is, the direction in which the slit-shaped flow path extends). In this configuration, the heat sink has a high cooling performance in the mainstream direction due to the fact that the distance from the entrance of the slit-shaped flow path varies depending on each heating element and the heat load of each heating element is different. It can be divided into a required part and a part where a relatively low cooling performance is allowed.

  Here, in the design of the heat sink, it is common to set various parameters such as the number of fins and the area of the fins so that desired cooling performance is ensured in a portion where high cooling performance is required. is there. However, when the number of fins is set on the basis of such a part that requires high cooling performance, for example, as a result of an increase in the number of fins, the slit-like flow path formed between adjacent fins In some cases, the width becomes narrow and the pressure loss of the entire heat sink increases. The increase in the pressure loss causes a disadvantage that the power of the blower must be increased in the forced air cooling heat sink as described in Patent Document 3.

  The technology disclosed herein has been made in view of such a point, and the object is to reduce the pressure loss of the heat sink while ensuring the desired cooling performance in a portion where high cooling performance is required. There is to do.

  In the heat sink in which a plurality of heating elements are arranged side by side in the main flow direction of the cooling air, the inventors of the present application allow a portion requiring high cooling performance and a relatively low cooling performance in the main flow direction as described above. However, only for parts that require high cooling performance, the cooling air flow rate is locally increased to increase cooling performance, while relatively low cooling performance is allowed. With regard to, if the configuration is such that the flow velocity of the cooling air is relatively lowered to reduce the pressure loss, the pressure loss of the entire heat sink is reduced while ensuring the desired cooling performance in the part where high cooling performance is required. Focusing on the fact that this is possible, the present invention has been completed.

  The technology disclosed herein includes a base configured to have a heating element attached to one surface, and a heat radiating unit configured to include a plurality of fins standing on the other surface of the base. The present invention relates to a heat sink comprising: a main body; and a restricting portion configured to restrict a flow direction of cooling air supplied to the heat sink main body in a main flow direction passing through the heat radiating portion.

  The fin extends in a standing direction from the proximal end that contacts the other surface of the base toward the distal end, and extends from a front end corresponding to the upstream end in the main flow direction to a rear end corresponding to the downstream end. The plurality of fins are arranged at predetermined intervals in the arrangement direction orthogonal to the main flow direction in the heat radiating portion, so that the fins are arranged between the adjacent fins. A plurality of slit-like flow paths that open at the front end, the rear end, and the front end of the fin are partitioned so as to extend in the main flow direction, and a plurality of the heating elements are formed in the base in the main flow direction. The heat sink body is mounted in a predetermined arrangement side by side, whereby the heat sink body is a first part that requires high cooling performance based on the heat load and arrangement of the heating element in the mainstream direction. When, is divided into a second portion where the lower cooling performance than the first region is allowed.

  And the regulation part has an opposing wall surface arranged so as to face the standing direction with respect to the base over the entire region in the mainstream direction of the heat dissipation part on the fin tip side of the heat dissipation part, The first opposing wall surface at a position corresponding to the first part has a narrow interval with the base, and the second opposing wall surface at a position corresponding to the second part has an interval with the base, It is set wider than the interval between the first portions.

  Here, the “first part” and the “second part” are the level of the thermal load of the plurality of heating elements attached to the base, the distance from the front end inlet of the slit-shaped flow path formed in the heat radiating part, Is set according to Specifically, the part where the heating element having a relatively high heat load is arranged can be a first part that requires a relatively high cooling performance. In addition, even if the heating elements have high heat loads, the heating elements arranged near the front end inlet can be sufficiently cooled because the temperature of the cooling air is low in the first place, but far from the front end inlet. At the position, since the temperature of the cooling air is relatively increased, the temperature of the heating element disposed therein is likely to be high, and higher cooling performance is required. Therefore, the part corresponding to the heating element arranged at a position far from the front end entrance can be the first part. Such a first part may be set at only one place (for example, a part having the highest temperature) or at a plurality of places in the heat sink body.

  According to the above configuration, the flow direction of the cooling air supplied to the heat sink body is regulated by the regulating unit so as to flow in the mainstream direction passing through the heat radiating unit. Specifically, the restricting portion has an opposing wall surface disposed so as to face the base in the standing direction over the entire region in the mainstream direction of the heat sink body on the fin tip side of the heat radiating portion. That is, the cooling air flows between the base of the heat sink body and the opposing wall surface. The heat of each heating element attached to the base is radiated from the base through each fin.

  A plurality of heating elements are arranged side by side in the main flow direction of the cooling air on the base, and the heat sink body is a first part that requires high cooling performance based on the heat load and arrangement of each heating element in the main flow direction. And a second part that allows lower cooling performance than the first part.

  Thus, in the above configuration, the first opposing wall surface at the position corresponding to the first portion requiring high cooling performance has a relatively narrow distance from the base, while low cooling performance is allowed. The second opposing wall surface at a position corresponding to the two parts is relatively wide from the base. With this configuration, as described above, the cooling air flows between the base and the opposing wall surface, but the cross-sectional area of the flow path through which the cooling air flows is relatively narrow at the position corresponding to the first portion. Since they are equivalent, the flow velocity of the cooling air is increased, which is advantageous for improving the cooling performance. As a result, high cooling performance is ensured in the first part. On the other hand, the position corresponding to the second part is equivalent to a relatively large cross-sectional area of the flow path through which the cooling air flows, so that the flow velocity of the cooling air is reduced and the cooling performance is It becomes low compared with. On the other hand, the pressure loss decreases. As a result, the second portion contributes to a decrease in pressure loss as the entire heat sink body. Accordingly, by appropriately setting the first part and the second part and setting the positions of the first and second opposing wall surfaces so as to correspond to the first part and the second part, in the heat sink, at a necessary part (that is, the first part). This ensures both high cooling performance and reduced pressure loss for the entire heat sink. Here, the length in the main flow direction of each heating element and the length in the main flow direction of the first part and the second part may be matched, but it is not always necessary to match.

  The restricting portion accommodates the heat radiating portion and is disposed at a position corresponding to the first portion of the heat sink main body in the duct extending in the main flow direction and constituting the second opposing wall surface. And a wind regulating portion that constitutes the first opposed wall surface at a position closer to the base than the second opposed wall surface of the duct, and the wind conditioned portion passes through the duct in the main flow direction. The flow direction of the cooling air is changed from the second opposing wall surface of the duct toward the heat radiating portion on the upstream side of the first opposing wall surface by interfering with the cooling air flowing through It is good as it is.

  By doing so, cooling air is supplied to the heat sink body through the duct. The flow direction of the cooling air is regulated by the inner peripheral surface of the duct, and a part of the inner peripheral surface of the duct is disposed so as to face the base of the heat sink body, so that the second opposing wall surface extending in the main flow direction. Configure.

  In the duct, a wind control portion constituting the first opposing wall surface is also disposed at a position corresponding to the first portion of the heat sink body. The first facing wall surface of the air conditioning section is disposed at a position closer to the base than the second facing wall surface of the duct. Thereby, the distance between the first opposing wall surface of the air conditioning unit and the base is relatively narrow, and the distance between the second opposing wall surface of the duct and the base is relatively wide. Further, the air conditioning unit interferes with the cooling air flowing in the main flow direction in the duct, so that the flow direction of the cooling air flows from the second opposing wall surface of the duct toward the heat radiating unit on the upstream side of the first opposing wall surface. Change to That is, the air conditioning unit has a function of forcibly changing the flow direction of the cooling air by blocking that the cooling air flowing in the main flow direction flows in the main flow direction as it is. Thus, in the first portion where the air conditioning section is arranged, the cooling air flows between the first opposing wall surface and the base, and the cross section of the flow path is temporarily restricted. The cooling air flowing in the mainstream direction temporarily increases at this first portion. As a result, relatively high cooling performance is ensured in the first part.

  In addition, you may make it change the shape of a duct itself instead of arrange | positioning an air conditioning part in a duct. That is, the cross-sectional shape of the duct is set so that the opposing wall surface at the position corresponding to the first part of the opposing wall surface constituted by the duct is closer to the base than the opposing wall surface at the position corresponding to the second part. You may make it squeeze temporarily in the middle. Even in such a configuration, it is possible to reduce the pressure loss as a whole of the heat sink while ensuring relatively high cooling performance in the first portion.

  A gap extending in the main flow direction may be provided between the heat radiating part and the second opposing wall surface of the duct, and the air conditioning part may be disposed in the gap.

  By providing a gap between the heat dissipating part and the second opposing wall surface of the duct, the pressure loss as a whole heat sink is reduced, while at the position corresponding to the first part, an air conditioning part is arranged in the gap. Thus, as described above, it becomes possible to temporarily narrow the cross section of the flow path to increase the cooling air speed, and it is possible to ensure a relatively high cooling performance for the first part.

  The air conditioning unit includes a plate member that extends in the main flow direction in the vicinity of the fin tip of the heat radiating unit at a position corresponding to the first part and forms the first opposing wall surface, and the plate member and the second of the duct. It is good also as having a connection part which obstruct | occludes between the said board | plate material and the said 2nd opposing wall surface by connecting between these opposing wall surfaces.

  In the air conditioning unit having this configuration, the connecting part that connects the plate material and the second opposing wall surface of the duct closes the space between the plate material and the second opposing wall surface of the duct so that the cooling air passes. Therefore, the cooling air flowing in the duct in the main flow direction passes between the first opposing wall surface constituted by the plate material and the base at the position of the first portion where the air conditioning section is disposed. Become. Therefore, in the first portion, the flow passage cross section is temporarily restricted and the cooling air speed is increased, so that high cooling performance is ensured.

  Moreover, since the wind control part of this structure is comprised by a board | plate material and a connection part, weight reduction is achieved. This is an advantageous configuration when the heat sink is mounted on a moving body such as a railway vehicle.

  The air conditioning unit may be arranged to extend from one end to the other end of the heat radiating unit in the duct.

  As described above, the air conditioning unit interferes with the cooling air flowing in the main flow direction in the duct, so that the pressure loss increases as the air conditioning unit is disposed in the duct. Here, if the air conditioning section is arranged only in a part of the fin arrangement direction in the duct, the pressure loss is not uniform in the arrangement direction, and a distribution of the pressure loss occurs. This causes the cooling air flowing in the duct to flow in an uneven direction, and may adversely affect the cooling performance of the heat sink depending on the arrangement of the heating elements.

  On the other hand, the arrangement of the air conditioned part extending from one end to the other end in the duct in the duct makes the pressure loss even in the line direction, and as a result, ensures the cooling performance of the heat sink appropriately. to enable.

  The heat sink body may be a forced air cooling type to which the cooling air from a blower is supplied.

  In the forced air-cooled heat sink, the reduction in pressure loss has the advantage that the power of the blower can be reduced. Further, the pressure loss can be reduced by, for example, narrowing the fin pitch in the heat dissipating section, thereby securing an increase in cooling performance. That is, there is an advantage that the degree of freedom in designing the heat sink is increased.

  As described above, according to the heat sink described above, in the first portion where high cooling performance is required, the cooling air speed is increased by narrowing the distance between the opposing wall surface and the base, and the desired high cooling performance. In the second portion where low cooling performance is allowed while securing the above, it is possible to reduce the pressure loss of the entire heat sink by widening the gap between the opposing wall surface and the base.

(A) Partial sectional view of heat sink, (b) Bottom view of heat sink. It is II-II sectional drawing of FIG. (A)-(c) It is a modification which concerns on the structure of an air conditioning part. (A)-(d) It is another modification which concerns on the structure of an air conditioning part. It is a modification which concerns on arrangement | positioning of a wind regulation part. It is another modification which concerns on arrangement | positioning of a wind control part. It is a modification which concerns on the structure of a duct. (A) (b) It is a modification which concerns on the structure of a heat sink main body. (A) (b) It is a side view which shows the structural example of a fin. It is a figure which shows the relationship between the air volume and pressure loss which concern on an Example. It is a figure which shows the relationship between the distance from the inlet_port | entrance of the heat sink main body which concerns on an Example, and a temperature rise value.

  Hereinafter, an embodiment of a heat sink will be described based on the drawings. In addition, the following description of preferable embodiment is an illustration. 1A is a partial sectional view of a heat sink, FIG. 1B is a bottom view of the heat sink, and FIG. 2 is a sectional view taken along the line II-II in FIG. The heat sink 1 is a cooler for cooling the heating elements 21 and 22 such as a power semiconductor element used for driving a railway vehicle. However, it may be used for other purposes.

  The heat sink 1 includes a heat sink body and a duct 61 that houses the heat sink body. In the following description, the heat sink body is simply referred to as a “heat sink” and is given the reference numeral 1. The duct 61 is connected to a blower (not shown), and the cooling air from the blower is ducted as shown by arrows in FIG. 1 (solid arrows in FIG. 1 (a) and dashed-dotted arrows in FIG. 1 (b)). Through 61, the heat sink 1 is supplied. In the following, the flow direction of the cooling air in the duct 61 is referred to as a main flow direction, which is the direction from the left to the right in FIG. The heat sink 1 is a forced air cooling type heat sink 1, and the heat sink 1 radiates heat of the heat generating elements 21 and 22 to cool the heat generating elements 21 and 22. The heat sink 1 includes a base 11 to which the heating elements 21 and 22 are attached, and a heat radiating unit 3 including a plurality of fins 31 erected with respect to the base 11.

  The base 11 is a flat plate having a predetermined thickness while extending in the front-rear direction (that is, the mainstream direction) corresponding to the direction of the duct 61 and the arrangement direction orthogonal to the front-rear direction. The base 11 has a mounting surface (that is, a lower surface in FIG. 1A) 111 to which the heating elements 21 and 22 are mounted, and a heat dissipation surface (that is, an upper surface in FIG. 1A) 112 on which the fins 31 are erected. , And is configured in the thickness direction. A plurality of heating elements 21 and 22 are attached to the attachment surface 111 of the base 11 in contact with the attachment surface 111 with grease having high thermal conductivity interposed therebetween. In the illustrated example, a total of 16 heating elements 21 and 22 are arranged in a matrix so that there are four in the front-rear direction and four in the arrangement direction. Among these heating elements 21, 22, the heating elements 21 arranged in the two rows on the front side have a relatively high heat load, and the heating elements 22 arranged in the two rows on the rear side have a relatively high heat load. Has been lowered. Thus, the heat loads of the heating elements 21 and 22 arranged side by side in the mainstream direction are different, and the distance from the front end inlet of each slit-like flow path 30 of the heat radiating unit 3 described later is the heating elements 21 and 22. In this heat sink 1, as shown in FIG. 1B, the heat sink 1 is relatively different from the portion (that is, the first portion) that requires relatively high cooling performance in the mainstream direction. Even if the cooling performance is very low, it is classified into an allowable part (that is, the second part). Here, the part where the heat generating element 21 having a high heat load is disposed can be the first part, but even if the heat load is the same, the position close to the front end inlet of the slit-like flow path 30 (that is, the front and rear) The heating element 21 arranged in the first row in the direction has a relatively low temperature of the cooling air, so that the required cooling performance is easy to secure, whereas the heating element 21 is located far from the front end entrance (that is, in the front-rear direction). Since the temperature of the cooling air is relatively high, the heating elements 21 arranged in the second row are difficult to ensure the required cooling performance, and become the first part that requires particularly high cooling performance. . In this example, the portion having the highest temperature in the heat sink 1 is set as the first portion. Note that the length in the front-rear direction of the first part and the length in the front-rear direction of the heating elements 21 and 22 do not necessarily match, and at least a part of the first part and the heating element overlap in the mainstream direction. Set to In the illustrated example, only one first part is set, but there may be a case where a plurality of first parts are set. Furthermore, FIG. 1 is only an example of the arrangement of the heating elements, and the arrangement of the heating elements is appropriately set. Since the first part and the second part are set according to the arrangement of the heating elements, the setting of the first part and the second part may be different from FIG.

  Each fin 31 is a flat plate having a certain thickness, and extends in a direction orthogonal to the heat radiating surface 112 from the base end that contacts the heat radiating surface 112 of the base 11 (that is, in the standing direction). It is erected on the heat radiating surface 112 so as to extend, and is disposed extending in the front-rear direction. The shape of each fin 31 is not limited to the illustrated example, and the ratio of the height, the length in the front-rear direction, and the thickness can be set as appropriate.

  The plurality of fins 31 are arranged in parallel with the heat dissipating surface 112 of the base 11 at predetermined equal intervals in the arrangement direction. In the illustrated example, 23 fins 31 are arranged side by side, but the number of fins 31 of the heat dissipating unit 3 is not limited to this. A slit-like flow path 30 extending along the front-rear direction is defined between the side surfaces of adjacent fins 31 in the heat radiating unit 3 (see FIG. 2). Each slit-like channel 30 opens at each of the front end (left end in FIG. 1A), rear end (right end in FIG. 1A), and tip (upper end in FIG. 1A) of the fin 31. It will be. In addition, the channel width of the slit-shaped channel 30 can be set to an appropriate width, and is not limited to the illustrated example.

  The heat sink 1 is formed of a material having high thermal conductivity, such as aluminum or an aluminum alloy. The heat sink 1 may be formed by joining the fins 31 to the base 11 by various appropriate means such as welding, brazing, and adhesive.

  Here, although not shown in FIG. 1 and the like, as shown in FIG. 9A or 9B, one side of each fin 31, that is, one side, protrudes from the side of the fin 31, A plurality of convex portions 51 are provided in a predetermined arrangement. 9A and 9B, the arrangement pattern of the convex portions 51 is different. Such a convex part 51 may be formed by press molding, for example.

  The plurality of convex portions 51 have a function of promoting heat transfer by making the flow in the slit-shaped flow path 30 turbulent. Further, the plurality of convex portions 51 provided in a predetermined arrangement are arranged so that the cooling air flowing in from the front end inlet of the slit-shaped flow path 30 is the base end side of the fin 31 as indicated by an arrow in FIG. To increase the flow velocity in the vicinity of the base 11 of the heat sink 1. This is advantageous in enhancing the cooling effect of the heating elements 21 and 22.

  By providing the convex portion 51 in this manner, increasing the flow velocity in the vicinity of the base 11 is combined with the air conditioning unit 63 described below to narrow the cross section of the flow path, thereby greatly improving the cooling performance of the heat sink 1. In addition, it is also possible to omit the formation of the convex portion 51.

  Returning to FIGS. 1 and 2, a mounting seat 62 is attached to the fin tip of the heat radiating portion 3 of the heat sink 1, and the duct 61 is fixed to the heat sink 1 through the mounting seat 62.

  In the illustrated example, the mounting seat 62 has a rectangular cross section and a rectangular bar shape that extends across the entire region from one end to the other end in the direction in which the heat dissipating units 3 are arranged. The mounting seats 62 are disposed at the front end, the rear end, and the central three places in the heat radiating section 3. The mounting seat 62 can be joined to the heat radiating portion 3 by various appropriate means such as welding, brazing, and adhesive. For example, when the fins 31 are brazed to the base 11, the three mounting seats 62 may be brazed to the fins 31 at the same time.

  As shown in FIG. 2, the duct 61 is formed in a substantially hat-like cross section, and is disposed so as to cover the heat radiating portion 3 of the heat sink 1, and is joined to each of the mounting seat 62 and the base 11. ing. Thus, the duct 61 and the heat sink 1 are coupled to each other in a state in which the heat radiation portion 3 of the heat sink 1 is housed in the duct 61. The coupling of the duct 61 and the heat sink 1 via the mounting seat 62 has an advantage that the two can be coupled without requiring high dimensional accuracy. Further, the mounting seat 62 increases the strength of the heat sink 1 and contributes to the improvement of the overall rigidity.

  Here, the ceiling surface in the duct 61 is arranged away from the fin tips in the heat dissipating part 3 of the heat sink 1 by the amount of the mounting seat 62 interposed. Thus, a predetermined gap is provided between the heat radiating portion 3 and the ceiling surface of the duct 61 so as to extend in the main flow direction along the duct 61, and the gap extending in the main flow direction is It is closed by each of the mounting seats 62 arranged at the three positions of the front end, the center, and the rear end. Thus, the clearance is closed by the mounting seat 62 (hereinafter also referred to as the front end mounting seat) attached to the front end of the heat radiating portion 3, so that the cooling air flowing in the duct 61 opens at the front end of the heat radiating portion 3. Although flowing into each slit-shaped flow path 30, on the downstream side of the front end mounting seat 62, a part of the cooling air flows through the opening at the front end of each slit-shaped flow path 30, and the ceiling surface of the heat radiating unit 3 and the duct 61. And flows in the mainstream direction in the gap.

  Similarly, since the central mounting seat 62 mounted at the center of the heat radiating section 3 also closes the gap, the cooling air flowing in the main flow direction in the gap enters each slit-like channel 30 through the opening at the tip. It flows in and flows between the central mounting seat 62 and the base 11 in each slit-like flow path 30. In addition, on the downstream side of the central mounting seat 62, a part of the cooling air flows in the gap, and all the cooling air flows again in the slit-like flow passages 30 in the rear end mounting seat 62. It flows between the rear end mounting seat 62 and the base 11.

  Accordingly, in the heat sink 1, the cooling air flows between the front end mounting seat 62 and the central mounting seat 62, and between the central mounting seat 62 and the rear end mounting seat 62, respectively, and the ceiling surface of the duct 61 and the base 11. In the mounting positions of the front end mounting seat 62, the central mounting seat 62 and the rear end mounting seat 62, they pass between the mounting seat 62 and the base 11. The duct 61 constitutes a restricting portion configured to restrict the flow direction of the cooling air supplied to the heat sink 1 to the main flow direction passing through the heat radiating portion 3, and the ceiling surface of the duct 61 is a fin of the heat radiating portion 3. On the front end side, a part of the opposing wall surface is arranged across the entire region in the mainstream direction of the heat radiating portion 3 so as to face the base 11 with the heat radiating portion 3 interposed therebetween (that is, the second wall surface). Corresponds to the opposite wall).

  In such a configuration, although a part of the cooling air passes through the gap between the heat radiating unit 3 and the ceiling surface of the duct 61, the pressure loss is reduced, but the cooling performance can also be lowered. As a result, there may be a case where the desired cooling performance cannot be ensured in the first portion where high cooling performance is required.

  In view of this, in the heat sink 1, the air conditioning unit 63 is disposed in the duct 61 so as to partially improve the cooling performance in the first part. In the example of FIGS. 1 and 2, the air conditioning unit 63 is disposed in a part corresponding to the second row of heating elements 21 (in other words, the first part). It is comprised by the board | plate material 64 which continues to the center attachment seat 62. FIG.

  As shown in FIGS. 1 and 2 (in FIG. 1B, the plate member 64 is indicated by a one-dot chain line), the plate member 64 has a predetermined distance from the front end of the central mounting seat 62 (at the first part). It is configured to extend over the entire region from one end to the other end in the arrangement direction of the heat dissipating section 3, as well as the central mounting seat 62. In the illustrated example, the plate member 64 is disposed in contact with the tips of the fins 31 of the heat radiating unit 3, thereby closing the tip openings of the slit-like channels 30. It should be noted that a slight gap may be provided between the plate member 64 and the tip of each fin 31, and in this case as well, it is possible to achieve substantially the same operational effect as the speed increasing effect described later.

  Basically, the plate material 64 is not required to have heat conductivity, so there is no particular restriction on the material thereof, and the plate material 64 can be made of an appropriate material. The plate member 64 may be attached to the central mounting seat 62 using, for example, mechanical coupling means such as screwing, bonding, and caulking, or at the same time as the central mounting seat 62 is brazed, You may make it braze with respect to the center attachment seat 62. FIG.

  The cooling air flowing through the gap between the heat radiating section 3 and the ceiling of the duct 61 on the downstream side of the front end mounting seat 62 by the air conditioning section 63 configured as described above is because the central mounting seat 62 blocks the gap. As shown by the white arrow in FIG. On the upstream side of the front end of the plate member 64, the flow direction is changed in the direction from the ceiling surface of the duct 61 toward the heat radiating unit 3, and flows into the slit-shaped flow paths 30 through the opening at the front end. Then, at the position where the air conditioning unit 63 is disposed, cooling air flows between the lower surface of the plate member 64 and the base 11. As a result, in the first portion where the air conditioning unit 63 is disposed, the cross section of the flow path through which the cooling air flows is narrowed, so that the cooling air temporarily increases. Thus, high cooling performance can be ensured in the first part. Therefore, the lower surface of the plate member 64 is disposed in the vicinity of the fin tip of the heat radiating portion 3 so as to extend in the mainstream direction, and constitutes a first opposing wall surface facing the base 11 with the heat radiating portion 3 interposed therebetween, The mounting seat 62 connects the plate member 64 and the ceiling surface of the duct 61 (that is, the second opposing wall surface), thereby forming a connecting portion that closes the space between the plate member 64 and the second opposing wall surface. To do.

Further, the air conditioning unit 63 is provided only at a position corresponding to the first part, and at the position corresponding to the second part, the cooling air is a gap between the ceiling surface of the duct 61 and the tip of the heat radiating unit 3. In other words, it flows between the ceiling surface and the base 11. This is equivalent to the fact that the cross section of the flow path through which the cooling air flows is relatively wide, so that the speed of the cooling air is relatively reduced and the pressure loss is also reduced. Therefore, in the first part, it is possible to suppress the pressure loss as a whole of the heat sink 1 while ensuring high cooling performance. This has an advantage that the power of the blower can be reduced in the forced air-cooled heat sink 1. Reducing the power of the blower is advantageous in reducing power consumption and noise, and also has the advantage that an inexpensive blower can be used. Further, the pressure loss can be reduced by, for example, narrowing the fin pitch in the heat dissipating section 3 to ensure an increase in cooling performance.

(Modification)
FIG. 3 shows a modification of the air conditioning unit 63. In addition, illustration of a heat generating body is abbreviate | omitted in FIG. As shown in FIG. 5A, the plate member 64 may be configured to extend a predetermined distance from the rear end of the mounting seat 62 toward the rear. In this configuration, the flow direction of the cooling air is changed in the direction from the ceiling surface of the duct 61 toward the heat radiating portion 3 on the upstream side of the front end of the mounting seat 62, as indicated by the white arrow in the figure, Thereafter, the cooling air flows between the lower surface of the plate 64 and the base 11. That is, the air conditioning unit 63 shown in FIG. 3A also has substantially the same effect as the air conditioning unit 63 shown in FIG.

  3 (b), the plate member 64 is attached so as to extend a predetermined distance from the front end of the mounting seat 62 toward the front, and from the rear end of the mounting seat 62 to the rear. It is attached so as to extend a predetermined distance toward it.

  Further, in the modification shown in FIG. 3C, the plate member 64 is omitted, while the length of the mounting seat 62 in the main flow direction is increased, whereby the first opposing wall surface is formed by the lower surface of the mounting seat 62. This is an example of configuration. Such a wind control portion (that is, the mounting seat 62 itself) has the same effect. However, since the air conditioning unit 63 using the plate material 64 described above can be reduced in weight, it is advantageous for a heat sink mounted on a moving body such as a railway vehicle.

  The configuration shown in FIGS. 1 to 3 uses the mounting seat 62 for the duct 61 to form the wind regulating portion 63, but the wind regulating portion 63 is attached to the front end side of the fin 31 like the mounting seat 62. Thus, it is possible to use a rigid member for increasing fin rigidity.

  The modification shown in FIG. 4 has shown the structural example of the air conditioning part 65 which does not utilize an attachment seat. In FIG. 4, the heating element is not shown. That is, as shown in FIG. 4A, the air conditioning unit 65 includes a plate member 651 and a connecting portion 652 that connects the plate member 651 and the ceiling surface of the duct 61. The connecting portion 652 is integrated with the plate member 651 at the front end of the plate member 651, and the air conditioning unit 65 has an L-shaped cross section as a whole. The air conditioning unit 65 having such a configuration also has the same effects as the air conditioning unit 63 described above because the connecting unit 652 blocks the space between the heat radiation unit 3 and the ceiling of the duct 61. Since the air conditioning unit 65 can be disposed in the duct 61 independently of the mounting seat 62, the position of the first portion determined by the layout of the heating elements 21 and 22 and the mounting seat 62 is determined. This is effective in the case where the deviation occurs.

  As shown in FIG. 4B, the air conditioner 65 may be configured by disposing the connecting portion 652 at the rear end of the plate member 651. As shown in FIG. 4C, the connecting portion 652 is provided. You may arrange | position in the center of the board | plate material 651 and may comprise reverse T shape. Further, as shown in FIG. 4D, the connecting portions 652 and 652 may be arranged at the front end and the rear end of the plate member 651, respectively, and may be configured in a U shape.

  FIG. 5 shows a modified example related to the arrangement in the arrangement direction of the air conditioning unit. The air conditioning unit 63 shown in FIG. 1 is arranged at the same position in the front-rear direction in the arrangement direction, but the air conditioning unit 66 shown in FIG. 5 is divided into two on one side and the other side in the arrangement direction. Therefore, they are displaced in the front-rear direction. This is because, as shown in FIG. 5, the arrangement of the heat generating elements 21 having a relatively high heat load is different from the one side and the other side in the arrangement direction, and thus the first portion where high cooling performance is required is This is effective when there is a shift in the front-rear direction between one side and the other side of the arrangement direction. For example, if the length of the air conditioning unit in the front-rear direction is increased, the two first parts that are displaced in the front-rear direction can be handled by one air conditioning unit. The area will be enlarged. This can increase the pressure loss. The configuration described above is advantageous in setting the pressure loss of the entire heat sink 1 as low as possible because the region where the air conditioning unit 66 is disposed is minimized in the entire heat sink 1.

  FIG. 6 shows still another modified example related to the arrangement in the arrangement direction of the air conditioning unit. As shown virtually in the figure, for example, the air conditioning unit 67 is not arranged over the entire region from one end to the other end in the arrangement direction, but has a relatively high thermal load as shown in FIG. Corresponding to the fact that the heating elements 21 are arranged in a part of the arrangement direction, they may be arranged only in a part of the arrangement direction. In the illustrated example, the air conditioning unit 67 is disposed only in the center portion in the arrangement direction. This also increases the cooling air speed at the portion where the air conditioning unit 67 is disposed, thereby improving the cooling performance. However, in the configuration in which the air conditioning unit 67 is arranged only in a part of the arrangement direction, the pressure loss in the duct 61 becomes uneven with respect to the arrangement direction. The configuration shown in FIG. 6 is preferably applied in a configuration in which the influence of the drift of the cooling air does not become a problem.

  The modified example shown in FIG. 7 does not have the air conditioning part disposed in the duct, but has the same effect as the air conditioning part by changing the shape of the duct itself. That is, the duct 68 shown in FIG. 7 is provided with a recess 681 in the ceiling wall at a location corresponding to the first part, and the recess 681 extends in the alignment direction, which is a direction orthogonal to the paper surface in FIG. Is provided. By the recess 681, the ceiling surface in the duct 68 constitutes both the first opposing wall surface and the second opposing wall surface. Accordingly, in the duct 68, the cooling air flowing in the mainstream direction between the ceiling surface constituting the second opposing wall surface of the duct 68 and the tip of the heat radiating portion 3 is indicated by a white arrow in the figure, The flow direction is changed on the upstream side of the recess 681, and at the position of the recess 681, the flow between the first opposing wall surface and the base 11 flows in a place where the flow path cross-section is temporarily restricted. Become. Thus, in the first part, it is possible to reduce pressure loss while ensuring high cooling performance.

  FIG. 8 shows a modification regarding the fins of the heat sink 1. In this modification, the tip of the fin 32 is in contact with the ceiling surface of the duct 61 without providing a gap between the ceiling surface of the duct 61 and the tip of the heat radiating unit 3. Further, in each fin 32, a concave portion 321 that is recessed from the distal end toward the proximal end is formed at a location corresponding to the first portion. In the example shown in FIG. 8A, the air conditioning unit 65 having the same configuration as that shown in FIG. 4B is disposed in the recess 321. In such a configuration, in the heat sink 1 shown in FIG. 4B, the height of the fin 31 is increased at a location other than the location where the air conditioning unit 65 is provided, so that the ceiling surface of the duct 61 and the heat radiating unit 3 In other words, it is a configuration in which the gap is eliminated. In the example shown in FIG. 8B, an air conditioning unit 62 (a mounting seat in FIG. 3C) having the same configuration as that shown in FIG. 3C is disposed in the recess 321 provided in the fin 32. Yes. Any of the configurations shown in FIGS. 1, 3 (a) to 3 (c) and FIGS. 4 (a) to (d) may be adopted for the air conditioning unit disposed in the recess 321.

  In the heat sink 1 shown in FIGS. 8 (a) and 8 (b), the cooling air flowing in each slit-like flow path of the heat radiating section 3 cannot pass through the recess 321 in which the air conditioned sections 62 and 65 are disposed. The cross section of the flow path is temporarily restricted, and the cooling air speed increases. As a result, the pressure loss of the entire heat sink can be reduced while ensuring high cooling performance in the first part. In the modification shown in FIG. 8, the heat transfer area of the fin 32 is made as wide as possible.

  In the configuration shown in FIG. 8, the concave portions 321 are formed in the fins 32, and the air conditioning portions 62 and 65 extending in the alignment direction are not disposed, but individually in each slit-like flow path, You may employ | adopt the structure which arrange | positions an air conditioning part.

  In each of the above-described configurations, the present technology is applied to a forced air-cooled heat sink. However, the technology disclosed herein can also be applied to a traveling-air heat sink.

  Next, practical examples regarding the pressure loss and cooling performance of the heat sink 1 will be described. First, heat sink models according to the conventional example, the comparative example, and the example were created, and the relationship between the air volume and the pressure loss was compared (see FIG. 10). In any model, as shown in FIG. 1B, a total of 16 heating elements are arranged by arranging four heating elements in each of the main flow direction and the arrangement direction, and the two heating elements in the front row are relative to each other. The heat load was set high, and the rear two rows of heating elements were set relatively low. Therefore, the arrangement position of the heating elements in the second row from the front is set as the first part that has the highest temperature. In the embodiment shown by white circles in FIG. 10, as shown in FIGS. 1 and 2, the air conditioning unit 63 including the plate material 64 is disposed between the ceiling surface of the duct 61 and the heat radiating unit 3 at a position corresponding to the first part. The conventional example shown by the black square is an example in which the air conditioning part is not arranged in the gap between the ceiling surface of the duct 61 and the heat radiating part 3, and the comparative example shown by the white triangle is the duct. This is an example in which no gap is provided between the ceiling surface of 61 and the heat radiating portion 3.

  According to FIG. 10, the pressure loss is the lowest in the conventional example, and the pressure loss is the highest in the comparative example, while the pressure loss is between the conventional example and the comparative example in the example. That is, an increase in pressure loss of the entire heat sink 1 is suppressed.

  Next, for each of the conventional example, the comparative example, and the example, the relationship between the distance from the front end inlet of the slit-like flow path 30 in the heat sink 1 and the temperature rise value was compared (see FIG. 11). Here, the temperature increase value is a value obtained by subtracting the temperature at the front end inlet from the temperature of the mounting surface of the heating elements 21 and 22 at each position of the heat sink 1. According to the figure, although the pressure loss is low as described above in the conventional example indicated by the black square, the temperature rise value is the highest, and the required cooling performance cannot be ensured particularly in the first part. On the other hand, in the comparative example shown by the white triangle, although the temperature rise value is the lowest, the pressure loss becomes high as described above.

  On the other hand, in the example, the temperature rise value in the first part is lower than that in the conventional example, and the required cooling performance can be ensured. In addition, in the example, particularly on the outlet side (second part) of the slit-like flow path 30, the temperature becomes as high as that of the conventional example, but the allowable cooling performance is ensured in the second part. . Therefore, the embodiment can reduce the pressure loss of the entire heat sink while ensuring the required high cooling performance in the first part.

  As described above, the heat sink disclosed here can reduce the pressure loss of the heat sink while ensuring the desired cooling performance in a portion where high cooling performance is required. Useful as a heat sink to perform.

1 Heat sink (heat sink body)
11 Base 3 Radiating section 30 Slit-shaped flow path 31 Fin 32 Fin 61 Duct (Regulator, second facing wall surface)
62 Mounting seat (connecting part)
63 Air conditioning unit 64 Plate material (first facing wall surface)
65 Air Conditioning Unit 651 Plate Material 652 Connection Unit 66 Air Conditioning Unit 67 Air Conditioning Unit 68 Duct (Regulator, first opposing wall surface, second opposing wall surface)

Claims (6)

A heat sink body having a base configured to attach a heating element to one surface, and a heat radiating portion configured to include a plurality of fins standing on the other surface of the base;
A heat sink comprising: a restricting portion configured to restrict a flow direction of the cooling air supplied to the heat sink body in a main flow direction passing through the heat radiating portion;
The fin extends in a standing direction from the proximal end that contacts the other surface of the base toward the distal end, and extends from a front end corresponding to the upstream end in the main flow direction to a rear end corresponding to the downstream end. Extending in the mainstream direction,
A plurality of the fins are arranged at predetermined intervals in the arrangement direction orthogonal to the mainstream direction in the heat radiating portion, so that the front end, the rear end, and the front end of the fins are adjacent to each other between the fins. A plurality of slit-like flow paths that are open in each of them are partitioned to extend in the front-rear direction,
A plurality of the heating elements are attached to the base in a predetermined arrangement in the main flow direction, whereby the heat sink body is based on the heat load and arrangement of the heating elements in the main flow direction. Are divided into a first part that requires high cooling performance and a second part that allows lower cooling performance than the first part,
The restricting portion has an opposing wall surface disposed so as to face the base in the standing direction over the entire region in the main flow direction of the heat radiating portion on the fin tip side of the heat radiating portion,
The first opposing wall surface at a position corresponding to the first part has a narrow interval with the base, and the second opposing wall surface at a position corresponding to the second part has an interval with the base, A heat sink that is set wider than the interval between the first portions. The heat sink according to claim 1.
The regulation part is
A duct that houses the heat dissipating part and extends in the mainstream direction to form the second opposing wall surface;
The wind control which is arrange | positioned in the said duct in the position corresponding to the said 1st site | part of the said heat sink main body, and comprises the said 1st opposing wall surface in the position near the said base rather than the said 2nd opposing wall surface of the said duct. And
The air conditioning unit interferes with the cooling air flowing in the main flow direction in the duct, thereby changing the flow direction of the cooling air to the second opposing wall surface of the duct on the upstream side of the first opposing wall surface. A heat sink configured to change in a direction toward the heat radiating portion. The heat sink according to claim 2,
A gap extending in the mainstream direction is provided between the heat radiating portion and the second opposing wall surface of the duct,
The air conditioning unit is a heat sink disposed in the gap. The heat sink according to claim 2 or 3,
The air conditioning unit includes a plate member that extends in the main flow direction in the vicinity of the fin tip of the heat radiating unit at a position corresponding to the first part and forms the first opposing wall surface, and the plate member and the second of the duct. A heat sink comprising: a connecting portion that closes between the plate member and the second opposing wall surface by connecting between the opposite wall surfaces. The heat sink according to any one of claims 2 to 4,
The air conditioning unit is a heat sink that extends from one end to the other end of the heat dissipating unit in the duct. The heat sink according to any one of claims 1 to 5,
The heat sink body is a heat sink that is a forced air cooling type to which the cooling air from a blower is supplied.

Images