WO2019138564A1 - Heat-sink - Google Patents

Abstract

This heat-sink (1) comprises a base section (3), gap-securing members (5), thermal radiation fins (7), and top plate metal pieces (9). Each of the thermal radiation fins (7) has a width (W) in the X-direction and a length (H) in the Z-direction. Each of the thermal radiation fins (7) has a first edge portion (7a) and a second edge portion (7b) opposing one another across the length (H). Of the thermal radiation fin (7), the first edge portion (7a) is fixed to the base section (3), and the second edge portion (7b) side serves as an open edge side. In a mode that links the second edge portion (7b) of one of the thermal radiation fins (7) to the second edge portion (7b) of another thermal radiation fin (7), each of the top plate metal pieces (9) is connected to the second edge portions (7b) of the thermal radiation fins (7). The top plate metal pieces (9) extend in the Y-direction.

Description

heatsink

The present invention relates to a heat sink, and more particularly to a heat sink provided with heat dissipating fins.

In recent years, electronic components such as large-scale integrated circuits (LSI) represented by central processing units (CPUs) have become popular as electronic devices have become extremely dense or high in frequency. The heat generated by parts is a concern at the time of design. Heat sinks are utilized to dissipate the heat generated from the electronic components.

While the heat generated can be dissipated by the heat sink, the heat sink may cause an electrical resonance at a frequency of the wavelength due to the length of the heat dissipating fin which dissipates the heat. Heretofore, it has been limited that the frequency of the clock signal of the system has an electrical influence on the heat sink.

However, in recent systems, with the progress of multiple clock signals and high frequency, the heat sink has come to behave as a radiation source of electromagnetic noise. That is, noise is superimposed on the heat sink by conducting the noise of the printed circuit board to the heat sink, or, for example, by coupling the component or wiring on the printed circuit board with the heat sink, the heat sink acts as an antenna, and the noise is secondary. The radiation may cause a system malfunction.

In addition to being a source of noise, the heat sink may also act as a good noise receiving antenna. For this reason, it may become impossible to satisfy the standard value of various EMC (Electro-Magnetic Compatibility) certification tests. For this reason, in the design of the heat sink, not only securing of the heat dissipation which is the original purpose, but also a design in consideration of electromagnetic noise is required, and various proposals have been made.

For example, Patent Document 1 proposes a heat sink in which the length of the radiation fin is not matched with the signal frequency of the system or the half wavelength of the harmonic frequency of the signal frequency. Moreover, in patent document 2, the heat sink provided with the radiation fin which disperse | distributed the resonant frequency is proposed.

Unexamined-Japanese-Patent No. 2000-156578 (patent 300982) Japanese Patent Laid-Open No. 2000-305273

As mentioned above, in recent systems, operation is performed by a large number of clock signals. Moreover, transmission and reception of data are performed based on the fundamental frequency of various digital I / F (Inter Face). Therefore, it is difficult to design the length of the radiation fin so as not to match the reference signal such as a clock signal or its harmonic frequency.

Specifically, when the length of the heat dissipating fin is shortened, the heat dissipating property, which is the original purpose of the heat sink, may be impaired. On the other hand, when the length of the radiation fin becomes long, for example, it may be necessary to redesign the housing. For this reason, in the heat sink proposed in Patent Document 1, it is assumed that if both heat dissipation and electromagnetic noise reduction are attempted, design restrictions increase and it becomes difficult to design with a high degree of freedom. Be done.

On the other hand, in the heat sink proposed in Patent Document 2, since it is necessary to design a radiation fin having different lengths and metal materials, it is assumed that the design and manufacture of the heat sink become complicated.

The present invention has been made in view of the above-described problems, and an object thereof is to provide a heat sink capable of achieving design freedom and reducing electromagnetic noise.

The heat sink according to the present invention has a base portion and a plurality of heat radiation fins. The base portion is mounted on the printed circuit board and electrically connected to any of the signal ground potential, the frame ground potential and the ground of the printed circuit board. The plurality of heat dissipating fins are spaced apart from each other on the base portion and electrically connected to the base portion. Among the plurality of heat dissipating fins, the portion of one of the heat dissipating fins and the portion of the other heat dissipating fin are electrically conductive members on the open end side of the plurality of heat dissipating fins opposite to the side attached to the base portion. Are electrically connected.

According to the heat sink of the present invention, at the open end side of the plurality of radiation fins, the portion of one of the plurality of radiation fins and the portion of the other radiation fin are electrically connected by the conductive member It is done. Thus, in the heat sink, the impedance on the open end side of the plurality of heat radiation fins can be reduced, and the electromagnetic noise can be returned to any of the signal ground potential, the frame ground potential and the ground of the printed circuit board. As a result, as a heat sink, the degree of freedom in design can be achieved and the strength of the electromagnetic noise can be reduced without being restricted by the wavelength of the electromagnetic wave and without being restricted by the material of the radiation fin.

It is a perspective view which shows an example of the state in which the heat sink which concerns on Embodiment 1 of this invention was mounted in the printed circuit board. In the same embodiment, it is a side view showing an example of a state where a heat sink was mounted in a printed circuit board. In the embodiment, it is a partially enlarged perspective view showing a connection aspect between the heat radiation fin and the upper sheet metal. It is a perspective view which shows the state in which the heat sink which concerns on a comparative example was mounted in the printed circuit board. It is a perspective view which shows an example of the state in which the heat sink which concerns on Embodiment 2 of this invention was mounted in the printed circuit board. It is a perspective view which shows an example of the state in which the heat sink which concerns on the 1st example of Embodiment 3 of this invention was mounted in the printed circuit board. In the embodiment, it is a partial enlarged perspective view of a radiation fin. In the embodiment, it is a partially expanded perspective view which shows the connection aspect of a radiation fin and a projection part. It is a perspective view which shows an example of the state in which the heat sink which concerns on the 2nd example of Embodiment 3 of this invention was mounted in the printed circuit board. In the embodiment, it is a partially expanded perspective view which shows the connection aspect of a radiation fin and a projection part. It is a perspective view which shows an example of the state in which the heat sink which concerns on Embodiment 4 of this invention was mounted in the printed circuit board. In the embodiment, it is an expansion perspective view showing an example of a connection member. FIG. 16 is an enlarged perspective view showing another example of the connection member in the embodiment. It is a perspective view which shows an example of the state in which the heat sink which concerns on Embodiment 5 of this invention was mounted in the printed circuit board.

Embodiment 1
The heat sink according to the first embodiment will be described.

As shown in FIGS. 1 and 2, the heat sink 1 is mounted on, for example, a printed circuit board 51. An electronic component 53 is mounted on the printed circuit board 51. The heat sink 1 is disposed in contact with the electronic component 53. The heat generated from the electronic component 53 such as a large scale integrated circuit is dissipated through the heat sink 1. The structure of the heat sink 1 will be described in detail.

The heat sink 1 includes a base portion 3, a gap securing member 5, a plurality of heat radiation fins 7, and an upper sheet metal 9 as a conductive member. The base portion 3 is flat and has a constant thickness. The gap securing member 5 secures a space between the base portion 3 and the printed circuit board 51 such that the base portion 3 contacts or approaches the electronic component 53. When metal gap securing member 5 can not be applied, base member 3 and printed circuit board 51 can be electrically connected by separately providing a conductive member such as a screw, an on-board contact or a gasket. It may be connected to

Each of the plurality of heat dissipating fins 7 has a width W in the X direction, and has a length H extending in the Z direction. Each of the plurality of heat dissipating fins 7 has a first end 7 a and a second end 7 b opposite to each other across the length H. The plurality of radiation fins 7 are disposed in the base portion 3 at an interval from each other in the Y direction. The first end 7 a of the radiation fin 7 is fixed to the base 3. The second end 7 b side of the radiation fin 7 is an open end side.

The plurality of heat dissipating fins 7 are formed of the same metal material, which has high thermal conductivity and high conductivity. Moreover, as for several radiation fin 7, it is desirable to form from the same size. The same size is not intended to be completely the same, but includes a manufacturing error. The heat dissipating fins 7 are preferably made of, for example, aluminum, an aluminum alloy, copper or the like.

The upper sheet metal 9 is connected to the second ends 7 b of the plurality of heat dissipating fins 7 in such a manner that the second end 7 b of one of the heat dissipating fins 7 adjacent to each other and the second end 7 b of the other heat dissipating fins 7 are connected. It is done. The upper sheet metal 9 extends in the Y direction. In addition, even if one radiation fin 7 and another radiation fin 7 are not adjacent to each other, the open end side of the plurality of radiation fins 7 may be electrically connected by the upper sheet metal 9 as a whole. Good.

Similar to the radiation fin 7, the base portion 3, the gap securing member 5 and the upper metal plate 9 are formed of a metal material having high thermal conductivity and high conductivity, and formed of, for example, aluminum, aluminum alloy or copper. Is desirable.

The open end sides of the plurality of heat radiation fins 7 are electrically connected by the upper metal plate 9. On the open end side of the radiation fin 7, the upper metal plate 9 needs to be connected at at least one place. In order to reduce the impedance of the heat dissipating fins 7, it is desirable that the heat dissipating fins 7 be connected by the upper sheet metal 9 at a plurality of locations. Further, as described later, it is also desirable to expand the width of the upper sheet metal 9. Here, as shown in FIG. 3, the two upper sheet metals 9 are connected to the end face 7bb of the second end 7b.

The upper sheet metal 9 is connected to the second end 7 b of the heat dissipating fin 7 by, for example, soldering or a conductive adhesive. Further, the upper sheet metal 9 and the heat dissipating fins 7 may be formed by integral molding.

The plurality of heat radiation fins 7 are electrically connected to, for example, the ground wiring 55 formed on the printed circuit board 51 through the base portion 3 and the space securing member 5. The base 3 (the gap securing member 5) and the ground wiring 55 need to be connected at at least one place. In order to reduce the impedance of the heat sink 1 with respect to the ground potential (earth) of the ground wiring 55, it is desirable that the base 3 and the ground wiring 55 be connected at a plurality of points.

In each embodiment, although the case where a plurality of radiation fins 7 are electrically connected to the ground wiring 55 (earth) is described as an example, the plurality of radiation fins 7 are electrically connected to the ground potential. It should just be connected. The ground potential depends on the ground design of the system with the heat sink, which includes the signal ground potential, the flame ground potential and the ground. The signal ground potential is a ground potential that is a reference of the circuit. The frame ground potential is the ground potential of the housing including the heat sink 1. Therefore, the plurality of heat radiation fins 7 may be electrically connected to any of the signal ground potential, the frame ground potential and the ground.

In the heat sink 1 described above, the open end sides of the plurality of heat radiation fins 7 are electrically connected by the upper sheet metal 9. Thereby, the intensity of the electromagnetic noise can be reduced. This will be described in comparison with the heat sink according to the comparative example.

FIG. 4 shows a general heat sink 1 in which the upper sheet metal is not disposed as a heat sink according to the comparative example. Here, the length in the Z direction of the radiation fin 7 of the heat sink 1 according to the comparative example is H, and the wavelength of the electromagnetic wave is λ. Then, the heat sink 1 (the plurality of heat radiation fins 7) is considered to be equivalent to a λ / 4 monopole antenna in which resonance occurs at a frequency corresponding to λ = 4 L and a frequency that is an odd multiple of the frequency. From the radiation fin 7, electromagnetic noise having high spectrum intensity is radiated at a frequency corresponding to the wavelength and its harmonic frequency.

Compared to the comparative example, in the heat sink 1 according to the first embodiment, the open end sides of the plurality of heat radiation fins 7 are electrically connected by the upper sheet metal 9. Further, the plurality of heat dissipating fins 7 are electrically connected to the ground wiring 55 of the printed circuit board 51 via the base portion 3 and the space securing member 5.

For this reason, in the heat sink 1, the impedance at the open end side of the plurality of heat radiation fins 7 can be reduced. Furthermore, the electromagnetic noise conducted to the heat sink 1 can be returned to the ground through the base portion 3 and the gap securing member 5.

Thereby, the radiation of the electromagnetic noise can be suppressed and the intensity of the electromagnetic noise can be reduced even if the length relationship of the heat radiation fin 7 is equivalent to the λ / 4 monopole antenna. it can. That is, as the heat sink 1, the degree of freedom in design can be achieved without being restricted by the wavelength of the electromagnetic wave and without being restricted by the material of the radiation fin 7, and the strength of the electromagnetic noise can be reduced. .

Moreover, when performing forced air cooling in the heat sink 1 which concerns on a comparative example, the case where a fan (not shown) is arrange | positioned so as to oppose the radiation fin 7 is assumed. In this case, the radiation fin 7 may vibrate due to the flow of air generated by the fan, and this vibration may be transmitted to the electronic component through the printed circuit board.

Compared to the comparative example, in the heat sink 1 according to the first embodiment, the open end sides of the plurality of heat radiation fins 7 are electrically and physically connected by the upper sheet metal 9. Thereby, even if the flow of air is generated by the fan (not shown), the vibration of the radiation fin 7 can be suppressed as a secondary effect of the upper plate metal 9.

Second Embodiment
A heat sink according to the second embodiment will be described.

As shown in FIG. 5, a wide upper sheet metal 11 is disposed in the heat sink 1 as a conductive member. The upper sheet metal 11 connects the second end 7b of one heat dissipating fin 7 and the second end 7b of the other heat dissipating fin 7 in the X direction at the second end 7b of the heat dissipating fin 7. From the one end to the other end, it is arranged to close the air gap between one radiation fin 7 and the other radiation fin 7 on the open end side.

The upper sheet metal 11 is connected to the second end 7 b of the heat radiation fin 7 by, for example, soldering or a conductive adhesive. Further, the upper sheet metal 11 may be formed integrally with the base portion 3 and the heat dissipating fins 7 by integral molding. The other components are the same as those of the heat sink 1 shown in FIG. 1 and the like, and therefore, the same members are denoted by the same reference numerals, and the description thereof will not be repeated unless necessary.

In the heat sink 1 described above, the wide upper metal plate 11 is disposed so as to cover the open end side from one end in the X direction to the other end of the second end 7 b of the heat radiation fin 7. For this reason, compared with the upper metal plate 9 (FIG. 1 etc.) with a narrow width | variety, the impedance at the open end side in the radiation fin 7 can be reduced more. Further, as described above, the electromagnetic noise conducted to the heat sink 1 can be returned to the ground via the base portion 3 and the gap securing member 5.

Thereby, even if the length H of the radiation fin 7 is a dimension equivalent to a λ / 4 monopole antenna, the radiation of the electromagnetic noise is reliably suppressed and the intensity of the electromagnetic noise is reduced. Can.

That is, in the heat sink 1 according to the second embodiment, the degree of freedom in design is achieved without being restricted by the wavelength of the electromagnetic wave and without being restricted by the material of the radiation fin 7, and the intensity of the electromagnetic noise Can be reduced.

Further, as in the heat sink 1 according to the first embodiment, in the heat sink 1 according to the second embodiment, the open end sides of the plurality of heat radiation fins 7 are electrically and physically connected by the upper sheet metal 11. Thereby, even if the flow of air is generated by the fan (not shown), the vibration of the radiation fin 7 can be suppressed as a secondary effect by the upper sheet metal 11.

Third Embodiment
(First example)
A first example of the heat sink according to the third embodiment will be described.

As shown in FIG. 6, the heat sink 1 is provided with a projection 13 with a relatively narrow width as a conductive member. As shown in FIG. 7, the protrusion 13 is provided on the second end 7 b of the heat radiation fin 7 so as to protrude in the Y direction. The protrusion 13 is provided with, for example, a passing portion 13a, an opening 13b, and a locking portion 13c.

As shown in FIG. 8, the passing portions 13 a are disposed so as to pass between one heat radiation fin 7 and another heat radiation fin 7 adjacent to each other. By inserting the locking portion 13 c of the protrusion 13 of one heat dissipating fin 7 into the opening 13 b of the protrusion 13 of the other heat dissipating fin 7, the protrusions 13 are mutually caulked, and one heat dissipating fin and the other heat dissipating fin And the radiation fins of the two are locked to each other. Hereinafter, in the same manner, the open end sides of the plurality of radiation fins 7 are locked to each other. The other components are the same as those of the heat sink 1 shown in FIG. 1 and the like, and therefore, the same members are denoted by the same reference numerals, and the description thereof will not be repeated unless necessary.

In the heat sink 1 described above, the open end sides of the plurality of heat radiation fins 7 are locked to each other by the projections 13 with a relatively narrow width. For this reason, the impedance at the open end side of the radiation fin 7 can be reduced. Further, as described in the first embodiment, the electromagnetic noise conducted to the heat sink 1 can be returned to the ground through the base portion 3 and the gap securing member 5.

Thereby, even if the length H of the radiation fin 7 is a dimension equivalent to the λ / 4 monopole antenna, the radiation of the electromagnetic noise is suppressed and the intensity of the electromagnetic noise can be reduced. .

That is, in the heat sink 1 according to the first example of the third embodiment, freedom of design is achieved without being restricted by the wavelength of the electromagnetic wave and without being restricted by the material of the radiation fin 7, and The intensity of electromagnetic noise can be reduced.

Further, as in the heat sink 1 according to the first embodiment, in the heat sink 1 according to the first example of the third embodiment, the open end sides of the plurality of radiation fins 7 are electrically and physically connected by the protrusions 13. It is done. Thereby, even if the flow of air is generated by the fan (not shown), the vibration of the heat dissipating fins 7 can be suppressed as a secondary effect by the protrusion 13.

In the heat sink 1 described above, the two protrusions 13 are provided at an interval in the X direction as an example, but at least one of the protrusions 13 at a desired position in the X direction. It should just be provided.

(Second example)
A second example of the heat sink according to the third embodiment will be described.

As shown in FIG. 9, the heat sink 1 is provided with a protrusion 15 having a relatively wide width as a conductive member. As shown in FIG. 10, the protrusion 15 is provided on the second end 7b of the heat radiation fin 7 so as to protrude in the Y direction. The protrusion 15 is provided with, for example, a passing portion 15a, an opening 15b, and a locking portion 15c.

The passing portion 15a is disposed so as to pass between one heat radiation fin 7 and another heat radiation fin 7 adjacent to each other. The passing portion 15a is disposed from one end to the other end of the second end 7b of the radiation fin 7 in the X direction so as to close a gap between the one radiation fin 7 and the other radiation fin 7 on the open end side. ing.

By inserting the locking portion 15 c of the protrusion 15 of one heat dissipating fin 7 into the opening 15 b of the protrusion 15 of the other heat dissipating fin 7, the protrusions 15 are caulked, and one heat dissipating fin and the other heat dissipating fin And the radiation fins of the two are locked to each other. Hereinafter, in the same manner, the open end sides of the plurality of radiation fins 7 are locked to each other. The other components are the same as those of the heat sink 1 shown in FIG. 1 and the like, and therefore, the same members are denoted by the same reference numerals, and the description thereof will not be repeated unless necessary.

In the heat sink 1 described above, the open end sides of the plurality of heat radiation fins 7 are engaged with each other so as to close the open end sides of the plurality of heat radiation fins 7 by the projections 15 having a relatively wide width. Thereby, the impedance at the open end side of the radiation fin 7 can be further reduced. Further, as described in the first embodiment, the electromagnetic noise conducted to the heat sink 1 can be returned to the ground through the base portion 3 and the gap securing member 5.

Thereby, even if the length H of the radiation fin 7 is a dimension equivalent to a λ / 4 monopole antenna, the radiation of the electromagnetic noise is reliably suppressed and the intensity of the electromagnetic noise is reduced. Can.

That is, in the heat sink 1 according to the second example of the third embodiment, the degree of freedom in design is achieved without being restricted by the wavelength of the electromagnetic wave and without being restricted by the material of the radiation fin 7, and The intensity of electromagnetic noise can be reduced.

Further, as in the heat sink 1 according to the first embodiment, in the heat sink 1 according to the second example of the third embodiment, the open ends of the plurality of heat radiation fins 7 are electrically and physically connected by the protrusions 13. It is done. Thereby, even if the flow of air is generated by the fan (not shown), the vibration of the heat dissipating fins 7 can be suppressed as a secondary effect by the protrusion 13.

Fourth Embodiment
A heat sink according to the fourth embodiment will be described.

As shown in FIG. 11, the heat sink 1 is provided with a connection member 17 as a conductive member. An example of the connection member 17 is shown in FIG. The connecting member 17 shown in FIG. 12 is provided with a passing portion 17a, a locking portion 17b and a locking portion 17c.

As shown in FIG. 11 and FIG. 12, the connection member 17 is disposed so as to straddle between one heat dissipating fin 7 and another heat dissipating fin 7 adjacent to each other. The passing portion 17 a is disposed so as to pass between one heat dissipating fin 7 and the other heat dissipating fin 7. The locking portion 17 b locks one radiation fin 7, and the locking portion 17 c locks another radiation fin 7.

The plurality of connecting members 17 are disposed at X-direction positions that do not interfere with each other. The other components are the same as those of the heat sink 1 shown in FIG. 1 and the like, and therefore, the same members are denoted by the same reference numerals, and the description thereof will not be repeated unless necessary.

In the heat sink 1 described above, the open end sides of the plurality of radiation fins 7 are mutually locked by the connection member 17. For this reason, the impedance of the open end side in the radiation fin 7 can be further reduced. Further, as described above, the electromagnetic noise conducted to the heat sink 1 can be returned to the ground via the base portion 3 and the gap securing member 5.

Thereby, even if the length H of the radiation fin 7 is a dimension equivalent to a λ / 4 monopole antenna, the radiation of the electromagnetic noise is reliably suppressed and the intensity of the electromagnetic noise is reduced. Can.

That is, in the heat sink 1 according to the fourth embodiment, the degree of freedom of design is achieved without being restricted by the wavelength of the electromagnetic wave and without being restricted by the material of the radiation fin 7, and the intensity of the electromagnetic noise Can be reduced.

Further, in the heat sink 1 according to the fourth embodiment, the open end sides of the plurality of heat radiation fins 7 are electrically and physically connected by the protrusions 13 as in the heat sink 1 according to the first embodiment. Thereby, even if the flow of air is generated by the fan (not shown), the vibration of the radiation fin 7 can be suppressed as a secondary effect by the connection member 17.

In addition to the connection member 17 shown in FIG. 12, the connection member 17 may be, for example, a connection member 17 in which the locking portion 17b and the locking portion 17c are arranged symmetrically as shown in FIG. .

Embodiment 5
A heat sink according to the fifth embodiment will be described.

As shown in FIG. 14, in the heat sink 1, a pair of side surface metal plates 19 is disposed as a conductive member. Each of the plurality of radiation fins 7 has a third end 7 c and a fourth end 7 d opposite to each other across the width W. One side surface metal plate 19 of the pair of side surface metal plates 19 is disposed at a portion of the third end 7 c of each of the plurality of heat radiation fins 7 located on the open end side. The other side surface metal plate 19 is disposed at a portion of the fourth end 7 d of each of the plurality of heat radiation fins 7 located on the open end side.

Here, one side surface metal plate 19 is disposed with a desired width from the portion connected to the second end 7 b in the third end 7 c to the first end 7 a side. The other side surface metal plate 19 is also disposed with a desired width from the portion of the fourth end 7 d connected to the second end 7 b to the first end 7 a side. The side surface metal plate 19 is connected to the third end 7 c and the fourth end 7 d of the heat radiation fin 7 by, for example, soldering or a conductive adhesive. The other components are the same as those of the heat sink 1 shown in FIG. 1 and the like, and therefore, the same members are denoted by the same reference numerals, and the description thereof will not be repeated unless necessary.

In the heat sink 1 described above, the third end 7 c and the fourth end 7 d of the plurality of heat radiation fins 7 are electrically connected by the side surface metal plate 19. For this reason, the impedance at the open end side of the radiation fin 7 can be reduced. Further, as described above, the electromagnetic noise conducted to the heat sink 1 can be returned to the ground via the base portion 3 and the gap securing member 5.

Thereby, even if the length H of the radiation fin 7 is a dimension equivalent to a λ / 4 monopole antenna, the radiation of the electromagnetic noise is reliably suppressed and the intensity of the electromagnetic noise is reduced. Can.

That is, in the heat sink 1 according to the fifth embodiment, the degree of freedom in design is achieved without being restricted by the wavelength of the electromagnetic wave and without being restricted by the material of the radiation fin 7, and the intensity of the electromagnetic noise Can be reduced.

In addition, since the side surface metal plate 19 is an alternative to the upper surface metal plates 9 and 11, etc., it is desirable that the upper portion of each of the third end 7c and the fourth end 7d of the radiation fin 7 be a position to arrange the side surface .

From the viewpoint of lowering the impedance of the radiation fin 7, even if the side plate 19 is disposed at the center of each of the third end 7c and the fourth end 7d of the radiation fin 7, the effect of reducing the electromagnetic noise can be obtained. it is conceivable that. Therefore, as a position which arrange | positions the side surface metal plate 19, the inside of the range of the center part in a 3rd end part 7c of the radiation fin 7 and the upper end part in each of the 4th end part 7d is desirable.

Further, as in the heat sink 1 according to the first embodiment, in the heat sink 1 according to the fifth embodiment, the open end sides of the plurality of heat radiation fins 7 are electrically and physically connected by the side surface metal plate 19. Thereby, even if the flow of air is generated by the fan (not shown), the vibration of the radiation fin 7 can be suppressed as a secondary effect by the side surface metal plate 19.

In each of the embodiments, the plate-like member is mainly described as an example of the conductive member, but it is not limited to the plate-like member as long as a plurality of heat radiation fins can be electrically connected. For example, it may be in the form of a tape having conductivity.

About the heat sink 1 provided with the upper sheet metal etc. as a conductive member demonstrated in each embodiment, it is possible to combine variously as needed.

The embodiment disclosed this time is an example and is not limited thereto. The present invention is not the scope described above, is shown by the claims, and is intended to include all modifications in the meaning and scope equivalent to the claims.

The present invention is effectively used for a heat sink provided with a plurality of radiation fins.

DESCRIPTION OF SYMBOLS 1 heat sink, 3 base part, 5 space | interval securing member, 7 radiation fin, 7a 1st end part, 7b 2nd end part, 7bb upper end surface, 7c 3rd end part, 7d 4th end part, 9, 11 upper sheet metal, 13, 15 Protrusions, 13a, 15a Crossing portions, 13b, 15b Openings, 13c, 15c Locking portions, 17 Connecting members, 17a Crossing portions, 17b Locking portions, 19 Side sheet metal, 51 Printed circuit boards, 53 Heating parts, 55 Ground wiring.

Claims (15)

A base portion mounted on a printed circuit board and electrically connected to any of the signal ground potential, the frame ground potential and the ground of the printed circuit board;
And a plurality of heat dissipating fins which are spaced apart from each other on the base portion and electrically connected to the base portion,
Among the plurality of heat dissipating fins, the portion of one of the heat dissipating fins and the portion of the other heat dissipating fin are on the open end side opposite to the side attached to the base portion in the plurality of heat dissipating fins; A heat sink electrically connected by a conductive member. Each of the plurality of heat dissipating fins has a width in a first direction and extends in a second direction intersecting the first direction,
The plurality of heat radiation fins are disposed on the base portion at an interval from each other in a third direction intersecting the first direction and the second direction,
Each of the plurality of radiation fins is
A first end attached to the base;
The first end has a distance in the second direction, and has a second end located on the open end side.
The heat sink according to claim 1, wherein the second end of the one radiation fin and the second end of the other radiation fin are electrically connected by the conductive member. The second end has an end face extending in the first direction,
The heat sink according to claim 2, wherein the conductive member is connected to the end surface. The heat sink according to claim 3, wherein the conductive member is plate-shaped. The heat sink according to claim 2, wherein the conductive member includes a first member and a second member spaced apart from each other in the first direction. The conductive member covers a gap between the one heat dissipating fin located on the open end side and the other heat dissipating fin from one end to the other end in the first direction at the second end. The heat sink of claim 2 connected to the second end. The heat sink according to claim 6, wherein the conductive member is plate-shaped. The conductive member is
A first protrusion provided at the second end of the one heat dissipating fin so as to project in the third direction and locking the other heat dissipating fin;
And a second protrusion provided at the second end of the other radiation fin so as to project in the third direction and for locking the further radiation fin adjacent to the other radiation fin. The heat sink according to claim 2. The first protrusion and the second protrusion are formed by the one heat dissipating fin and the other heat dissipating fin positioned on the open end side from one end to the other end in the first direction at the second end. 9. The heat sink according to claim 8, wherein the heat sink is provided at the second end to close an air gap therebetween. The heat sink according to claim 2, wherein the conductive member includes a connection member disposed so as to straddle the one radiation fin and the other radiation fin. Each of the plurality of heat dissipating fins has a width in a first direction and extends in a second direction intersecting the first direction,
The plurality of heat radiation fins are disposed on the base portion at an interval from each other in a third direction intersecting the first direction and the second direction,
Each of the plurality of radiation fins is
A first end attached to the base;
The third end and the fourth end face the first end at a distance in the second direction and face the second end located on the open end side at a distance in the first direction. Have a department,
The conductive member electrically connects the portion at the open end of the third end of the one heat dissipating fin with the portion at the open end of the third end of the other heat dissipating fin. The heat sink of claim 1, wherein the heat sink is The heat sink according to claim 11, wherein the conductive member is plate-shaped. And an interval holding member attached to the base and maintaining an interval between the base and the printed circuit board.
The plurality of heat dissipating fins are electrically connected to any of the signal ground potential of the printed circuit board, the frame ground potential, and the ground via the base portion and the spacing member. Heat sink. The heat sink according to claim 1, wherein the plurality of heat dissipating fins are formed of the same material. The heat sink according to claim 1, wherein the plurality of radiation fins are the same size.

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