JP5177794B2 - Radiator - Google Patents

Description

  The present invention relates to a radiator that is used in various electric equipments typified by, for example, a switching power supply device and radiates heat generated by a heating element such as a semiconductor element.

  In recent years, as the performance and size of electronic components have increased, the degree of integration and mounting density has increased, and the heat generation of electronic components has increased. Since the temperature rise in the apparatus affects the life of each electronic component and the reliability of operation, cooling measures are an issue. A semiconductor element that generates heat, for example, directs heat to a heat-dissipating part such as a heat-dissipating fin through a heat receiving plate that contacts the heat-generating element and receives heat from the heat-generating element. The radiator has reduced the temperature rise by cooling.

  3A and 3B show the structure of a conventional radiator. In the figure, 51 is a wiring pattern (not shown) such as a copper foil formed on one or both sides of a base material made of an insulator, and a conductive plated through hole 52 is provided at an appropriate position of the wiring pattern. Printed circuit board. Reference numeral 53 denotes a heating element having a plurality of lead terminals. Each lead terminal 54 of the heating element 53 is inserted into the corresponding through hole 52, and solder is melted and adhered between the lead terminal 54 and the through hole 52, so that the electrical connection between the printed circuit board 51 and the heating element 53 is achieved. Connection is made.

  On the other hand, 61 is a radiator for dissipating heat from the heating element 53. The heat radiator 61 includes a heat receiving plate 62 erected on the printed circuit board 51 so as to be aligned with the heat generating body 53, and heat radiating fins 63a as a plurality of heat radiating portions integrally formed on one side surface 62A of the heat receiving plate 62. , 63b, 63c. The heat radiating fins 63a, 63b, 63c are provided so as to protrude from the side surface 62A in the thickness direction of the heat receiving plate 62 at equal intervals, and are formed with the same protruding length L4 '. The heating element 53 is in contact with one side surface 62A of the heat receiving plate 62 and is fixed by screws 64.

As described above, in the conventional radiator 61, the heat of the heating element 53 made of a semiconductor element is quickly transferred from the heat receiving plate 62 to the radiation fins 63a, 63b, 63c by the radiator 61 made of a material having excellent thermal conductivity. Here, the heat from the blower is applied to the radiating fins 63a, 63b, and 63c to perform heat exchange, thereby cooling the heating element 53 and radiating heat into the air. The heat transfer action to the heat radiating fins 63a, 63b, and 63c first transfers heat to the heat radiating fins 63c located near the heating element 53, where it is radiated into the air by the air blown from the blower, and further radiated at this part. The heat that did not exist is transferred to the heat dissipating fins 63b and the heat dissipating fins 63a that are gradually separated from the heating element 53, and dissipated by blowing air (see Patent Document 1).
JP 2005-175225 A

  In the heat radiator 61 configured as described above, the heat generated from the heating element 53 is transmitted radially through the heat receiving plate 54 with the heating element 53 as the center. Specifically, heat is first transferred from the base of the heat receiving plate 54 to the heat dissipating fins 63c closest to the heat generating body 53, where heat is exchanged with the air passing around the heat dissipating fins 63c to dissipate heat. Further, the heat that could not be radiated by the radiating fin 63c is transferred from the heating element 53 to another radiating fin 63b that is the second closest to the heat radiating fin 63b. To do. Further, the heat that could not be radiated by the radiating fin 63b is transferred to the radiating fin 63a located farthest from the heating element 53, and similarly, heat is exchanged with the air passing around the radiating fin 63a to radiate it into the air. It is like that.

  However, both sides in the width direction of the radiating fins 63a and 63b are located farthest from the heating element 53, which is a heat source, so that heat from the heating element 53 is difficult to reach and is difficult to contribute to heat dissipation. For this reason, the radiation fins 63a and 63b in this portion are wasted, and the miniaturization of an electric device incorporating the radiator is hindered.

  In addition, when forced air is sent from one direction of the radiator 61 by the blower, the cooling performance may be lowered depending on the direction of the blow. For example, referring to FIG. 3A, the cooling air A from a blower (not shown) is not obliquely above the radiating fins 63a, 63b, 63c but obliquely above the radiating fins 63a, 63b, 63c as indicated by arrows. In a situation where the air is fed from the direction, the cooling air A is concentrated on one side in the width direction of the radiating fin 63a farthest from the heating element 53. When this happens, one side in the width direction of the heat radiating fin 63a, which is a part that hardly contributes to heat radiation, obstructs the cooling fin 63c from which heat from the heating element 53 is first transmitted, and the cooling air is less likely to hit effectively. There was a problem that the heat dissipation performance as the heat radiator 61 deteriorated.

  Therefore, an object of the present invention is to provide a radiator that can be reduced in size without deteriorating heat dissipation performance by effectively applying cooling air to a heat radiating portion close to a heating element.

  A radiator according to claim 1 of the present invention includes a heat receiving plate that contacts the heat generating element and receives heat from the heat generating element, and a plurality of heat dissipating parts that are arranged side by side along the width direction of the heat receiving plate. The length in the width direction of the heat receiving plate and the heat radiating portion is gradually shortened as the distance from the heating element increases.

  In the heat radiator according to claim 2 of the present invention, at least one heat radiating portion is also installed on the other side surface of the heat receiving plate.

  In the first aspect of the present invention, a plurality of heat radiating portions are arranged in parallel on one side of the heat receiving plate that is transferred to heat by contacting a heating element such as a semiconductor element, and the length in the width direction of the heat receiving plate and the heat radiating portion. However, the distance from the center of the heating element is gradually shortened. In this way, the cooling air is sent from an oblique direction of the heat radiating part by cutting the heat receiving plate and the heat radiating part which are located away from the center of the heat generating element and hardly contribute to heat radiation. However, the cooling air is effectively applied to the radiating fin to which the heat from the heating element is first transmitted, and the heat transmitted from the heating element can be effectively cooled to increase the heat radiation efficiency.

  In fact, the heat transmitted from the heat generating element to the heat radiating part through the heat receiving plate is less likely to be transmitted as the position from the heat generating element to the heat radiating part increases, and it is difficult to contribute to heat dissipation. Therefore, even if the heat receiving plate and the heat radiating portion that are unlikely to contribute to heat radiation are shortened, the heat radiating function is hardly affected. By cutting such a portion, the radiator can be miniaturized. Therefore, it is possible to provide a radiator that can be reduced in size without deteriorating the heat dissipation performance by effectively applying cooling air to the heat radiating portion close to the heating element.

  Further, in the invention of claim 2, since the heat radiating portion is similarly installed not only on one side of the heat receiving plate but also on the other side, the heat radiating performance as a radiator, that is, the cooling efficiency can be further enhanced. In addition, for example, when mounting on an electronic device, it is necessary to suppress the height of the radiator in terms of space, by providing a heat radiating part on the other side of the heat receiving plate, while maintaining the heat radiation performance, The height can be suppressed.

  Hereinafter, preferred embodiments of a radiator according to the present invention will be described with reference to the accompanying drawings. In the following embodiments, the same portions are denoted by the same reference numerals, and description of common portions is omitted as much as possible to avoid duplication.

  1A and 1B show a radiator 1 according to a first embodiment of the present invention. The radiator 1 is for radiating heat from the heating element 53, and is integrally formed on the heat receiving plate 2 standing on the printed circuit board 51 and one side surface 2A of the heat receiving plate 2 in the thickness direction. A plurality of heat radiation fins 3a, 3b, 3c are provided. The heat radiating fins 3a, 3b, 3c and the heat receiving plate 2 are integrally formed of a member such as aluminum that is lightweight and excellent in thermal conductivity. Further, the heat radiation fins 3a, 3b, 3c are provided in a comb-like shape from one side 2A of the heat receiving plate 2 so as to protrude in parallel at a predetermined pitch from the upper part of the heat generating body 53 to the upper end of the heat receiving plate 2. , Are formed with the same protruding length L4. The heating element 53 is in contact with one side surface 2A of the heat receiving plate 2 and is fixed by screws 64.

  As in the conventional example, the printed circuit board 51 is formed with a wiring pattern (not shown) such as a copper foil on one or both surfaces of a base material made of an insulator, and further, a conductive plated-through is placed at an appropriate position of the wiring pattern. A hole 52 is provided. Each lead terminal 54 of the heating element 53 is inserted into the corresponding through hole 52, and solder is melted and adhered between the lead terminal 54 and the through hole 52, so that the electrical connection between the printed circuit board 51 and the heating element 53 is achieved. Connection is made.

  The heat receiving plate 2 of the radiator 1 has a predetermined height from the portion in contact with the printed circuit board 51 to the upper end, and integrally forms the radiation fins 3a, 3b, 3c on the upper portion in the height direction, A heating element 53 is arranged at the bottom. Furthermore, in the present embodiment, the printed circuit board 51 and the printed circuit board 51 are arranged so that the radial distance from the heating element 53 to the edge of the heat receiving plate 2 is as equal as possible, with the heating element 53 thermally connected to the heat receiving plate 2 as the center. The lengths L1, L2, and L3 in the width (lateral) direction of the parallel heat receiving plate 2 and the heat radiation fins 3a, 3b, and 3c are gradually shortened as the distance from the heating element 53 increases. Here, by cutting the left and right end surfaces of the rectangular heat receiving plate 2 in an oblique direction and linearly, the length L1 in the width direction of the heat dissipating fin 3a located farthest from the heat generating element 53 becomes the heat dissipating fin. The length L2 in the width direction of the heat dissipating fin 3b located near the heat generating body 53 is shorter than 3a, and the length L2 in the width direction of the heat dissipating fin 3b is closer to the heat generating body 53 than the heat dissipating fin 3b. Is formed shorter than the length L3 in the width direction of the radiating fin 3c. Thus, by cutting in advance an unnecessary portion that is far from the heating element 53 as the heat radiator 1 and does not contribute to heat radiation, the heat radiation performance of the entire heat radiator is not affected, and the size can be reduced as compared with the conventional one. Can be realized.

  In the above configuration, the heat receiving plate 2 is configured such that the lengths L1, L2, and L3 in the width direction of the radiating fins 3a, 3b, and 3c are gradually shortened from both sides as the distance from the heating element 53 increases. The left and right end faces may be formed stepwise. In order to make the radial distance from the heating element 53 to the edge of the heat receiving plate 2 as equal as possible, the left and right end surfaces of the heat receiving plate 2 may be formed in a curved shape instead of a straight line. Also in this case, the lengths L1, L2, and L3 in the width direction of the heat receiving plate 2 and the heat radiation fins 3a, 3b, and 3c are maintained in a relationship of L1 <L2 <L3. Further, a thermal compound or the like may be interposed between the heating element 53 and the heat receiving plate 2 in order to increase the thermal conductivity between the heating element 53 and the heat receiving plate 2.

  Next, the effect | action is demonstrated about the heat radiator 1 of the said structure. The heat of the heating element 53 made of a semiconductor element is quickly transferred from the heat receiving plate 2 to the heat radiating fins 3a, 3b, 3c by the heat radiator 1 made of a material having excellent heat conductivity, and here, the heat from the blower is radiated. Heat exchange is applied to the fins 3a, 3b, 3c to cool the heating element 53 and dissipate heat into the air. The heat transfer action to the heat radiating fins 3a, 3b, 3c first transfers heat to the heat radiating fins 3b located near the heat generating body 53, where the heat is radiated into the air by air blown from a blower (not shown) and further radiated at this portion. The heat that could not be exhausted is transferred to the heat dissipating fins 3b and the heat dissipating fins 3a that are gradually separated from the heat generating body 53, and is dissipated by blowing air. When the cooling air from the blower flows in the lateral direction along the radiation fins 3a, 3b, 3c, the heat transmitted to the radiation fins 3a, 3b, 3c can be taken evenly.

  On the other hand, as shown in FIG. 1A, the cooling air A from the air blower is not parallel along the radiation fins 3a, 3b, 3c, but from diagonally above the radiation fins 3a, 3b, 3c as indicated by arrows. It is also assumed that it will be sent. However, in this case, the lengths L1, L2, and L3 in the width direction of the heat receiving plate 2 and the heat radiation fins 3a, 3b, and 3c are gradually shortened as the distance from the heating element 53 increases. Since the left and right end surfaces of the heat radiation fins 3a, 3b, 3c are obliquely cut, the cooling air flows without resistance around the left and right end surfaces of the heat radiation fins 3a, 3b, 3c, and the heat radiation fins are located in the vicinity of the heating element 53. Cooling air easily hits 3c. Therefore, the cooling air effectively strikes the heat dissipating fins 3c to which heat from the heat generating element 53 is transmitted first, and the heat dissipating device 1 can be downsized without deteriorating the heat dissipating performance.

  As described above, the heat radiator 1 in this embodiment is arranged side by side along the width direction of the heat receiving plate 2 and the heat receiving plate 2 that contacts the heat generating member 53 and receives heat from the heat generating member 53. It consists of heat radiation fins 3a, 3b, 3c as a plurality of heat radiation portions, and the length L1, L2, L3 in the width direction of the heat receiving plate 2 and the heat radiation fins 3a, 3b, 3c is more distant from the heating element 53. It gradually becomes shorter.

  In this case, a plurality of heat radiation fins 3a, 3b, 3c are arranged in parallel on one side surface 2A of the heat receiving plate 2 that is in contact with the heat generating body 53 such as a semiconductor element to transfer heat, and the heat receiving plate 2 and the heat radiation fin 3a. , 3b, 3c, the lengths L1, L2, L3 in the width direction are gradually formed shorter as the distance from the center of the heating element 53 increases. As described above, the heat receiving plate 2 and the heat radiating fins 3a, 3b, and 3c that are located away from the center of the heat generating body 53 and do not contribute to heat radiation are cut so that the heat radiating fins 3a, 3b, and 3c are inclined. Even when the cooling air is sent from the direction, the cooling air is effectively applied to the radiation fins 3c to which the heat from the heating element 53 is first transmitted, and the heat transmitted from the heating element 53 is effectively transmitted. Cooling can improve the heat dissipation efficiency.

  In fact, the heat transmitted from the heat generating body 53 to the heat radiation fins 3a, 3b, 3c through the heat receiving plate 2 is less likely to be transmitted as the distance from the heat generating body 53 to the heat radiation fins 3a, 3b, 3c increases, and it is difficult to contribute to heat radiation. Therefore, even if the heat receiving plate 2 and the heat radiation fins 3a, 3b, and 3c, which do not easily contribute to heat radiation, are shortened, the heat radiation function is hardly affected. Miniaturization is possible. Therefore, it is possible to provide a heat radiator that can be reduced in size without deteriorating the heat radiation performance by effectively applying cooling air to the heat radiation fins 3a, 3b, 3c close to the heating element 53.

  2A and 2B show a radiator 1 in the second embodiment of the present invention. The structure of the radiator 1 is almost the same as that of the first embodiment, and the difference is that not only the one side surface 2A in the thickness direction of the heat receiving plate 2 but also the other side surface 2B in the thickness direction is the radiation fins 3d, 3e. Is integrally formed in the same manner. That is, in the first embodiment, the plurality of heat radiation fins 3a, 3b, 3c are provided only on one side surface 2A of the heat receiving plate 2. However, the heat radiator 1 here has a plurality of heat radiation fins on one side surface 2A of the heat reception plate 2. In addition to the provision of 3a, 3b, 3c, a plurality of heat radiation fins 3d, 3e are also provided on the other side 2B of the heat receiving plate 2 in the same manner. The heat radiation fins 3d and 3e are provided in a comb-like shape from the other side surface 2B of the heat receiving plate 2 so as to protrude in parallel at a predetermined pitch, and here are formed with the same protrusion length L7. The plurality of heat radiation fins 3d and 3e may be provided at any position on the other side surface 2B of the heat receiving plate 2 as long as the pitch is a predetermined pitch.

  Also in this embodiment, the length L1, L2, L3, L5, L6 in the width (lateral) direction of the heat receiving plate 2 and the radiation fins 3a, 3b, 3c, 3d, 3e parallel to the printed circuit board 51 are the heating elements 53. The closer to the position, the shorter it is formed. Here, the left and right end surfaces of the rectangular heat receiving plate 2 are cut obliquely and linearly, so that one side of the heat receiving plate 2 in the width direction of the heat dissipating fins 3a located farthest from the heating element 53 is used. The length L1 is shorter than the length L2 in the width direction of the heat dissipating fin 3b located in the vicinity of the heat generating element 53, and the length L2 in the width direction of the heat dissipating fin 3b is shorter than the heat dissipating fin 3a. The heat dissipating fin 3c is formed shorter than the length L3 in the width direction of the heat dissipating fin 3c located near the heat generating element 53 rather than 3b, and is located farthest from the heat generating element 53 on the other side of the heat receiving plate 2. The length L5 in the width direction of 3d is formed to be shorter than the length L6 in the width direction of the heat radiation fin 3e located in the vicinity of the heat generating body 53 than the heat radiation fin 3d. Thus, by cutting in advance an unnecessary portion that is far from the heating element 53 as the heat radiator 1 and does not contribute to heat radiation, the heat radiation performance of the entire heat radiator is not affected, and the size can be reduced as compared with the conventional one. Can be realized. The rest of the configuration as the radiator 1 is common to the first embodiment.

In this embodiment, since the heat receiving plate 2 of the radiator 1 is connected to the heat generating body 53, the heat from the heat generating body 53 is located closest to the heat generating body 53 from the portion connected to the heat receiving plate 2. Heat is transferred to the heat dissipating fins 3c, where heat is exchanged with the air passing through the periphery of the heat dissipating fins 3c to dissipate heat, and the heat that could not be dissipated by the heat dissipating fins 3c is gradually dissipated from the heating element 53. Heat is transferred to the fins 3e, 3b, 3d, and 3a in order to radiate heat. Here, when the cooling air from the blower flows in the lateral direction along the radiation fins 3a, 3b, 3c, 3d, 3e, the heat transmitted to the radiation fins 3a, 3b, 3c, 3d, 3e is evenly distributed. Although it is possible to take away, as shown in FIG. 2A, the cooling air A from the air blower is sent from the diagonally upward direction of the radiation fins 3a, 3b, 3c, 3d, 3e as indicated by arrows. In addition, the lengths L1, L2, L3, L5, and L6 in the width direction of the heat receiving plate 2 and the heat radiation fins 3a, 3b, 3c, 3d, and 3e are gradually shortened as the distance from the heating element 53 increases. Since the left and right end surfaces of the heat receiving plate 2 and the radiation fins 3a, 3b, 3c, 3d, 3e are cut obliquely, there is no resistance to the cooling air around the left and right end surfaces of the radiation fins 3a, 3b, 3c, 3d, 3e. Flow, located near the heating element 53 Cooling air easily hits the heat dissipating fins 3c and the heat dissipating fins 3d. Therefore, also in this case, it is possible to effectively reduce the size of the radiator 1 without reducing the heat radiation performance by the cooling air effectively hitting the radiation fins 3c and the radiation fins 3d to which the heat from the heating element 53 is first transmitted. become.
Moreover, since the heat radiating fins 3d and 3e are provided not only on the one side surface 2A of the heat receiving plate 2 but also on the other side surface 2B of the heat receiving plate 2, the heat radiating performance as the heat radiator 1, that is, the cooling efficiency can be further enhanced. In addition, for example, in mounting on an electronic device, even if it is necessary to suppress the height of the radiator in terms of space or if it is necessary to suppress the height in terms of space, the heat radiation fins 3d and 3e are received by heat. By providing on the other side 2B of the plate 2, the height of the radiator 1 can be suppressed while maintaining the heat dissipation performance.

  As described above, in the second embodiment, at least one radiation fin 3d, 3e is also installed on the other side surface 2B of the heat receiving plate 2. Therefore, heat exchange is performed by using the radiation fin 3d, 3e. Thus, it is possible to provide a radiator that can further improve the heat dissipation performance, that is, the cooling efficiency. Furthermore, even when it is necessary to suppress the height in terms of space, the height of the radiator 1 can be suppressed while maintaining the heat dissipation performance by providing the radiation fins 3d and 3e on the other side 2B of the heat receiving plate 2. Can do.

  As another modification, for example, the heat radiation fins 3a, 3b, 3c and the heat radiation fins 3d, 3e may be provided symmetrically on the one side surface 2A and the other side surface 2B of the heat receiving plate 2, respectively. Further, in common with the first embodiment and the second embodiment, the heating element 53 may be attached to the other side surface 2B of the heat receiving plate 2, and in this case as well, the same effects as the above-described embodiments are exhibited. can do.

  In addition, a present Example is not limited to said each embodiment, A various deformation | transformation implementation is possible. For example, as the heat radiating portion, a plate in which a plurality of pins are arranged at a predetermined density may be applied instead of the plate-shaped heat radiating fins in the embodiment.

It is a front view of the heat radiator which shows 1st Example of this invention. It is a side view of the heat radiator which shows 1st Example of this invention. It is a front view of the heat radiator which shows 2nd Example of this invention. It is a side view of the heat radiator which shows 2nd Example of this invention. It is a front view of the heat radiator which shows the conventional Example. It is a side view of the heat radiator which shows the conventional Example.

Explanation of symbols

2 Heat receiving plate 2A One side 2B Other side 3a, 3b, 3c, 3d, 3e Radiation fin (heat radiation part)
53 Heating element

Claims (2)

  A heat receiving plate that contacts the heat generating element and receives heat from the heat generating element, and a plurality of heat radiating portions arranged in parallel on one side surface along the width direction of the heat receiving plate, the heat receiving plate and the heat radiating portion The heat radiator characterized by being formed so that the length of the width direction is gradually shortened, so that it is in the position away from the said heat generating body.   The heat radiator according to claim 1, wherein at least one heat radiating portion is installed on the other side of the heat receiving plate.

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