CN111567155B

CN111567155B - Heat radiator

Info

Publication number: CN111567155B
Application number: CN201880076912.3A
Authority: CN
Inventors: 平田干人; 石坂哲
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2018-01-15
Filing date: 2018-01-15
Publication date: 2022-11-08
Anticipated expiration: 2038-01-15
Also published as: KR102434571B1; JPWO2019138564A1; KR20200095542A; TW201933977A; TWI664896B; CN111567155A; JP7004746B2; WO2019138564A1

Abstract

A heat sink (1) is provided with a base (3), a gap securing member (5), a heat radiating fin (7), and an upper metal plate (9). The fins (7) each have a width (W) in the X direction and a length (H) extending in the Z direction. The heat sink (7) has a 1 st end (7 a) and a 2 nd end (7 b) that are opposed to each other with a distance (H) therebetween. The heat sink (7) has a 1 st end (7 a) fixed to the base (3) and a 2 nd end (7 b) side serving as an open end. The upper metal plate (9) is connected to the 2 nd end (7 b) of the heat sink (7) in such a manner that the 2 nd end (7 b) of one heat sink (7) is connected to the 2 nd end (7 b) of the other heat sink (7). The upper metal plate (9) extends in the Y direction.

Description

Heat radiator

Technical Field

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

Background

In recent years, with the remarkable increase in density and frequency of electronic devices, in electronic components such as Large-Scale integrated circuits (LSIs) represented by Central Processing Units (CPUs), heat generated from the electronic components is a concern in designing. In order to dissipate heat generated from the electronic component, a heat sink is sufficiently utilized.

The heat sink can dissipate the generated heat, and on the other hand, the heat sink may generate electrical resonance at a frequency of a wavelength due to the length of the heat sink that dissipates the heat. Conventionally, there is a limit to the electrical influence of the frequency of the clock signal of the system on the heat sink.

However, in recent systems, a high frequency has been developed with a large number of clock signals, and the heat sink operates as a radiation source of electromagnetic noise. That is, noise of the printed circuit board may be transmitted to the heat sink, or noise may be superimposed on the heat sink due to, for example, coupling between a component or a wiring on the printed circuit board and the heat sink, and the heat sink may operate as an antenna to secondarily radiate the noise, thereby causing malfunction of the system.

In addition, the radiator may operate not only as a radiation source of noise but also as a reception antenna of good noise. Therefore, the standard value of various EMC (Electro-Magnetic Compatibility) certification tests may not be satisfied. Therefore, in designing a heat sink, it is required to secure heat radiation which is an original purpose, and design in consideration of electromagnetic noise is also required, and various proposals have been made.

For example, patent document 1 proposes a heat sink in which the length of a heat sink is set so as not to coincide with the length of 1/2 wavelength of a signal frequency of a system or a harmonic frequency of the signal frequency. Further, patent document 2 proposes a heat sink including fins for dispersing a resonance frequency.

Documents of the prior art

Patent literature

Patent document 1: japanese patent laid-open publication No. 2000-156578 (Japanese patent No. 3008942)

Patent document 2: japanese patent laid-open No. 2000-305273

Disclosure of Invention

As described above, in recent systems, operation is performed using a large number of clock signals. Data is transmitted and received at the fundamental frequency of various digital I/F (interface). Therefore, it is difficult to design the length of the heat sink so as not to match the frequency of the reference signal such as the clock signal or the harmonic thereof.

Specifically, if the length of the heat sink is short, the heat dissipation performance, which is an original purpose of the heat sink, may be impaired. On the other hand, when the length of the heat sink is long, for example, redesign of the housing may be necessary. Therefore, in the heat sink proposed in patent document 1, when both securing heat radiation performance and reducing electromagnetic noise are intended to be achieved, it is expected that the design constraint increases, and it is difficult to design with a high degree of freedom.

On the other hand, in the heat sink proposed in patent document 2, since it is necessary to design the heat sink having different lengths and metal materials, it is expected that the design and manufacturing of the heat sink become complicated.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a heat sink which achieves a degree of freedom in design and a reduction in electromagnetic noise.

The heat sink of the present invention has a base and a plurality of fins. The base is mounted on the printed circuit board and electrically connected to any one of a signal ground potential, a frame ground potential, and a ground of the printed circuit board. The plurality of heat sinks are arranged on the base at intervals and electrically connected with the base. At an open end side of the plurality of heat radiating fins on a side opposite to a side attached to the base, a part of one of the plurality of heat radiating fins and a part of the other heat radiating fin are electrically connected by a conductive member.

According to the heat sink of the present invention, at the open end side of the plurality of fins, a part of one fin and a part of another fin of the plurality of fins are electrically connected by the conductive member. Thus, in the heat sink, the impedance of the open end sides of the plurality of fins can be reduced, and electromagnetic noise can be returned to any one of the signal ground potential, the frame ground potential, and the ground of the printed circuit board. As a result, the heat sink can be designed with a degree of freedom without being restricted by the wavelength of the electromagnetic wave and the material of the heat sink, and the intensity of the electromagnetic noise can be reduced.

Drawings

Fig. 1 is a perspective view showing an example of a state in which a heat sink according to embodiment 1 of the present invention is mounted on a printed circuit board.

Fig. 2 is a side view showing an example of a state where the heat sink is mounted on the printed circuit board in this embodiment.

Fig. 3 is a partially enlarged perspective view showing a connection form of the heat sink and the upper metal plate in the embodiment.

Fig. 4 is a perspective view showing a state in which the heat sink of the comparative example is mounted on a printed circuit board.

Fig. 5 is a perspective view showing an example of a state in which the heat sink according to embodiment 2 of the present invention is mounted on a printed circuit board.

Fig. 6 is a perspective view showing an example of a state in which a heat sink of embodiment 1 of embodiment 3 of the present invention is mounted on a printed circuit board.

Fig. 7 is a partially enlarged perspective view of the heat sink in this embodiment.

Fig. 8 is a partially enlarged perspective view showing a connection form of the heat sink and the protrusion in the embodiment.

Fig. 9 is a perspective view showing an example of a state in which the heat sink of embodiment 2 of embodiment 3 of the present invention is mounted on a printed circuit board.

Fig. 10 is a partially enlarged perspective view showing a connection form of the heat sink and the protrusion in the embodiment.

Fig. 11 is a perspective view showing an example of a state in which the heat sink according to embodiment 4 of the present invention is mounted on a printed circuit board.

Fig. 12 is an enlarged perspective view showing an example of the connecting member in this embodiment.

Fig. 13 is an enlarged perspective view showing another example of the connecting member in this embodiment.

Fig. 14 is a perspective view showing an example of a state in which the heat sink according to embodiment 5 of the present invention is mounted on a printed circuit board.

(description of reference numerals)

1: a heat sink; 3: a base; 5: a gap ensuring member; 7: a heat sink; 7a: 1 st end part; 7b: a 2 nd end portion; 7bb: an upper end surface; 7c: a 3 rd end portion; 7d: a 4 th end portion; 9;11: an upper metal plate; 13. 15: a protrusion portion; 13a, 15a: a bridge portion; 13b, 15b: an opening part; 13c, 15c: a fastening part; 17: a connecting member; 17a: a bridge portion; 17b: a fastening part; 19: a side metal plate; 51: a printed substrate; 53: a heat-radiating member; 55: and a ground wiring.

Detailed Description

Embodiment 1.

The heat sink of embodiment 1 will be described.

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

The heat sink 1 includes a base 3, a gap securing member 5, a plurality of fins 7, and an upper metal plate 9 as a conductive member. The base portion 3 is flat and has a certain thickness. The gap securing member 5 secures a space between the base 3 and the printed substrate 51 to bring the base 3 into contact with or close to the electronic component 53. In addition, when the metal gap securing member 5 cannot be used, a conductive member such as a screw, an on-board contact (on-board contact), or a spacer may be separately provided to electrically connect the base 3 and the printed circuit board 51.

Each of the plurality of fins 7 has a width W in the X direction, extends in the Z direction, and has a length H. The plurality of fins 7 have a 1 st end 7a and a 2 nd end 7b that are opposed to each other with a distance H therebetween. The plurality of fins 7 are disposed on the base 3 at intervals in the Y direction. The 1 st end 7a of the fin 7 is fixed to the base 3. The second end 7b of the heat sink 7 is open.

The plurality of heat sinks 7 are formed of the same metal material having high thermal conductivity and high electrical conductivity. Further, the plurality of fins 7 are preferably formed with the same size. Moreover, the same dimensions are not meant to be identical, including manufacturing tolerances. The heat sink 7 is preferably formed of, for example, aluminum, an aluminum alloy, or copper.

The upper metal plate 9 is connected to the 2 nd end portions 7b of the plurality of fins 7 in such a manner that the 2 nd end portions 7b of one fin 7 and the 2 nd end portions 7b of the other fin 7 adjacent to each other are connected. The upper metal plate 9 extends in the Y direction. Even when one heat sink 7 and the other heat sink 7 are not adjacent to each other, the open end sides of the plurality of heat sinks 7 may be electrically connected to each other through the upper metal plate 9.

As with the heat sink 7, the base 3, the gap securing member 5, and the upper metal plate 9 are preferably made of a metal material having high thermal conductivity and high electrical conductivity, for example, aluminum, an aluminum alloy, or copper.

The open end sides of the plurality of fins 7 are electrically connected by the upper metal plate 9. The upper metal plate 9 needs to be connected at least at one location on the open end side of the heat sink 7. In order to reduce the impedance of the heat sink 7, it is preferable that the heat sink 7 is connected at a plurality of portions by the upper metal plate 9. As described later, the width of the upper metal plate 9 is preferably increased. Here, as shown in fig. 3, two upper metal plates 9 are connected to the end face 7bb of the 2 nd end portion 7b.

The upper metal plate 9 is connected to the 2 nd end 7b of the heat sink 7 by, for example, welding or using an adhesive having conductivity. Further, the upper metal plate 9 and the heat sink 7 may be formed by integral molding.

The plurality of heat sinks 7 are electrically connected to, for example, a ground wiring 55 formed on the printed board 51 via the base 3 and the gap securing member 5. The base 3 (gap securing member 5) and the ground wiring 55 need to be connected at least at one place. In order to reduce the impedance of the heat sink 1 with respect to the ground potential (ground) of the ground wiring 55, the base 3 and the ground wiring 55 are preferably connected at a plurality of locations.

In the embodiments, the case where the plurality of heat sinks 7 are electrically connected to the ground wiring 55 (ground line) is described as an example, but the plurality of heat sinks 7 may be electrically connected to the ground potential. The ground potential differs depending on the ground design of the system on which the heat sink is mounted, and includes a signal ground potential, a frame ground potential, and a ground. The signal ground potential is a ground potential serving as a reference of the circuit. The frame ground potential is a ground potential of the housing including the heat sink 1. Therefore, the plurality of heat sinks 7 may be electrically connected to any one of the signal ground potential, the frame ground potential, and the ground.

In the heat sink 1, the open ends of the plurality of fins 7 are electrically connected to each other through the upper metal plate 9. This can reduce the intensity of electromagnetic noise. This case will be described in comparison with the heat sink of the comparative example.

Fig. 4 shows a general heat sink 1 in which an upper metal plate is not disposed, as a heat sink of a comparative example. Here, the length of the heat radiating fins 7 of the heat sink 1 of the comparative example in the Z direction is H, and the wavelength of the electromagnetic wave is λ. Then, the heat sink 1 (the plurality of fins 7) is considered to be equivalent to a λ/4 monopole antenna that generates resonance at a frequency corresponding to λ =4L and a frequency that is an odd multiple of the frequency. Electromagnetic noise having high spectral intensity at a frequency corresponding to the wavelength and its higher harmonic frequencies is emitted from the heat sink 7.

In contrast to the comparative example, in the heat sink 1 of embodiment 1, the open end sides of the plurality of fins 7 are electrically connected by the upper metal plate 9. The plurality of heat sinks 7 are electrically connected to the ground wiring 55 of the printed circuit board 51 via the base 3 and the gap securing member 5.

Therefore, in the heat sink 1, the impedance of the open end sides of the plurality of fins 7 can be reduced. Further, the electromagnetic noise conducted to the heat sink 1 can be returned to the ground line via the base 3 and the gap securing member 5.

Accordingly, even if the length H of the heat sink 7 is in a dimensional relationship equivalent to that of a λ/4 monopole antenna, radiation of electromagnetic noise can be suppressed, and the intensity of electromagnetic noise can be reduced. That is, the heat sink 1 is not restricted by the wavelength of the electromagnetic wave and is not restricted by the material of the heat radiating fin 7, and thus the degree of freedom in design can be achieved and the intensity of the electromagnetic noise can be reduced.

In the case where forced air cooling is performed in the heat sink 1 of the comparative example, a fan (not shown) is assumed to be disposed so as to face the heat radiation fins 7. In this case, the heat sink 7 may vibrate due to the flow of air generated by the fan, and the vibration may be transmitted to the electronic component via the printed circuit board.

In contrast to the comparative example, in the heat sink 1 of embodiment 1, the open end sides of the plurality of fins 7 are electrically and physically connected by the upper metal plate 9. Thus, even if air flows by a fan (not shown), vibration of the heat sink 7 can be suppressed as an additional effect by the upper metal plate 9.

Embodiment 2.

The heat sink of embodiment 2 will be described.

As shown in fig. 5, the upper metal plate 11 having a wide width is disposed on the heat sink 1 as a conductive member. The upper metal plate 11 is disposed so as to extend from one end to the other end in the X direction of the 2 nd end 7b of the fin 7 and close the gap between the one fin 7 and the other fin 7 on the open end side, in a state where the 2 nd end 7b of the one fin 7 and the 2 nd end 7b of the other fin 7 adjacent to each other are connected.

The upper metal plate 11 is connected to the 2 nd end 7b of the heat sink 7 by, for example, welding or using an adhesive having conductivity. The upper metal plate 11 may be formed by integral molding together with the base 3 and the heat sink 7. The other configurations are the same as those of the heat sink 1 shown in fig. 1 and the like, and therefore the same members are given the same reference numerals, and the description thereof will not be repeated unless necessary.

In the heat sink 1, the upper metal plate 11 arranged to be wide extends from one end to the other end of the 2 nd end portion 7b of the heat sink 7 in the X direction and closes the open end side. Therefore, the impedance of the open end side of the heat sink 7 can be further reduced as compared with the upper metal plate 9 (fig. 1 and the like) having a narrow width. As described above, the electromagnetic noise conducted to the heat sink 1 can be returned to the ground line via the base 3 and the gap securing member 5.

Thus, even if the length H of the heat sink 7 is equivalent to a λ/4 monopole antenna, radiation of electromagnetic noise can be reliably suppressed, and the intensity of electromagnetic noise can be reduced.

That is, in the heat sink 1 of embodiment 2, the degree of freedom of design can be achieved without being restricted by the wavelength of the electromagnetic wave and the material of the heat radiating fins 7, and the intensity of the electromagnetic noise can be reduced.

In the heat sink 1 of embodiment 2, the open end sides of the plurality of fins 7 are electrically and physically connected to each other by the upper metal plate 11, as in the heat sink 1 of embodiment 1. Thus, even if air flows by a fan (not shown), vibration of the heat sink 7 can be suppressed as an additional effect by the upper metal plate 11.

Embodiment 3.

(example 1)

A heat sink 1 of embodiment 3 will be described.

As shown in fig. 6, the conductive member is a protrusion 13 having a relatively narrow width and disposed on the heat sink 1. As shown in fig. 7, the protrusion 13 is provided on the 2 nd end 7b of the heat sink 7 so as to protrude in the Y direction. The protrusion 13 is provided with, for example, a bridge portion 13a, an opening portion 13b, and an engagement portion 13c.

As shown in fig. 8, the bridging portion 13a is arranged to bridge between one heat sink 7 and the other heat sink 7 adjacent to each other. The engagement portions 13c of the protrusions 13 of one heat sink 7 are inserted into the openings 13b of the protrusions 13 of the other heat sink 7, and the protrusions 13 are crimped to each other, thereby engaging the one heat sink with the other heat sink. Hereinafter, similarly, the open end sides of the plurality of fins 7 are engaged with each other. The other configurations are the same as those of the heat sink 1 shown in fig. 1 and the like, and therefore the same members are given the same reference numerals, and the description thereof will not be repeated unless necessary.

In the heat sink 1, the open end sides of the plurality of fins 7 are engaged with each other by the relatively narrow projections 13. Therefore, the impedance of the open end side of the heat sink 7 can be reduced. As described in embodiment 1, the electromagnetic noise conducted to the heat sink 1 can be returned to the ground line via the base 3 and the gap securing member 5.

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

That is, in the heat sink 1 of example 1 of embodiment 3, the degree of freedom in design is achieved and the intensity of electromagnetic noise can be reduced without being restricted by the wavelength of electromagnetic waves and the material of the heat radiating fins 7.

In addition, in the heat sink 1 of example 1 of embodiment 3, the open end sides of the plurality of fins 7 are electrically and physically connected by the protruding portions 13, as in the heat sink 1 of embodiment 1. Thus, even if air flows by a fan (not shown), vibration of the heat sink 7 can be suppressed as an additional effect by the protrusion 13.

In the heat sink 1, two protrusions 13 are provided at intervals in the X direction, but at least 1 protrusion 13 may be provided at a desired position in the X direction.

(example 2)

A 2 nd example of the heat sink of embodiment 3 will be described.

As shown in fig. 9, the conductive member is a protrusion 15 having a relatively wide width and disposed on the heat sink 1. As shown in fig. 10, the projecting portion 15 is provided on the 2 nd end portion 7b of the heat sink 7 so as to project in the Y direction. The protrusion 15 is provided with, for example, a bridge portion 15a, an opening portion 15b, and an engagement portion 15c.

The bridge portion 15a is configured to bridge between one heat sink 7 and the other heat sink 7 adjacent to each other. The bridge portion 15a is disposed so as to extend from one end to the other end of the 2 nd end portion 7b of the fin 7 in the X direction and to close a gap between the one fin 7 and the other fin 7 on the open end side.

The engagement portions 15c of the protrusion 15 of one heat sink 7 are inserted into the openings 15b of the protrusion 15 of the other heat sink 7, and the protrusions 15 are caulked to each other, so that the one heat sink and the other heat sink are engaged with each other. Hereinafter, similarly, the open end sides of the plurality of fins 7 are engaged with each other. The other configurations are the same as those of the heat sink 1 shown in fig. 1 and the like, and therefore the same members are given the same reference numerals, and the description thereof will not be repeated unless necessary.

In the heat sink 1, the open ends of the plurality of fins 7 are engaged with each other so that the open ends of the plurality of fins 7 are closed by the relatively wide protrusion 15. This can further reduce the impedance of the open end side of the heat sink 7. As described in embodiment 1, the electromagnetic noise conducted to the heat sink 1 can be returned to the ground line via the base 3 and the gap securing member 5.

That is, in the heat sink 1 of example 2 of embodiment 3, the degree of freedom in design is achieved and the intensity of electromagnetic noise can be reduced without being restricted by the wavelength of electromagnetic waves and the material of the heat radiating fins 7.

In addition, in the heat sink 1 of example 2 of embodiment 3, the open end sides of the plurality of fins 7 are electrically and physically connected by the protruding portions 13, as in the heat sink 1 of embodiment 1. Thus, even if air flows by a fan (not shown), vibration of the heat sink 7 can be suppressed as an additional effect by the protrusion 13.

Embodiment 4.

The heat sink of embodiment 4 will be described.

As shown in fig. 11, the connecting member 17 is disposed on the heat sink 1 as a conductive member. Fig. 12 shows an example of the connecting member 17. The connecting member 17 shown in fig. 12 is provided with a bridge portion 17a, an engagement portion 17b, and an engagement portion 17c.

As shown in fig. 11 and 12, the connecting member 17 is disposed so as to bridge between one heat sink 7 and the other heat sink 7 adjacent to each other. The bridge portion 17a is configured to bridge between one heat sink 7 and the other heat sink 7. The engaging portion 17b engages with one heat sink 7, and the engaging portion 17c engages with the other heat sink 7.

The plurality of connecting members 17 are disposed at positions in the X direction where they do not interfere with each other. The other configurations are the same as those of the heat sink 1 shown in fig. 1 and the like, and therefore the same members are given the same reference numerals, and the description thereof will not be repeated unless necessary.

In the heat sink 1, the open end sides of the plurality of fins 7 are engaged with each other by the connecting member 17. Therefore, the impedance of the open end side of the heat sink 7 can be further reduced. As described above, the electromagnetic noise conducted to the heat sink 1 can be returned to the ground line via the base 3 and the gap securing member 5.

That is, in the heat sink 1 of embodiment 4, the degree of freedom in design can be achieved and the intensity of electromagnetic noise can be reduced without being restricted by the wavelength of electromagnetic waves and the material of the heat dissipating fins 7.

In addition, in the heat sink 1 of embodiment 4, the open end sides of the plurality of fins 7 are electrically and physically connected by the protruding portions 13, as in the heat sink 1 of embodiment 1. Accordingly, even if air flows by a fan (not shown), vibration of the heat sink 7 can be suppressed as an additional effect by the connecting member 17.

Note that, as the connecting member 17, in addition to the connecting member 17 shown in fig. 12, for example, as shown in fig. 13, the connecting member 17 may be such that the engaging portions 17b and the engaging portions 17c are symmetrically arranged.

Embodiment 5.

A heat sink of embodiment 5 will be described.

As shown in fig. 14, a pair of side metal plates 19 as conductive members are disposed on the heat sink 1. Each of the plurality of fins 7 has a 3 rd end 7c and a 4 th end 7d facing each other with a width W therebetween. One side metal plate 19 of the pair of side metal plates 19 is disposed in a portion located on the open end side at the 3 rd end portion 7c of each of the plurality of fins 7. The other side metal plate 19 is disposed in a portion of each of the plurality of fins 7 located on the open end side at the 4 th end 7d.

Here, the one side surface metal plate 19 is disposed from the portion of the 3 rd end portion 7c connected to the 2 nd end portion 7b toward the 1 st end portion 7a side by a desired width. The other side metal plate 19 is also disposed from the 4 th end 7d to the 1 st end 7a with a desired width from the portion connected to the 2 nd end 7b. The side metal plates 19 are connected to the 3 rd end portion 7c and the 4 th end portion 7d of the heat sink 7 by, for example, welding or using an adhesive having conductivity. The other configurations are the same as those of the heat sink 1 shown in fig. 1 and the like, and therefore the same members are given the same reference numerals, and the description thereof will not be repeated unless necessary.

In the heat sink 1, the 3 rd end portion 7c and the 4 th end portion 7d of the plurality of fins 7 are electrically connected by the side metal plate 19. Therefore, the impedance of the open end side of the heat sink 7 can be reduced. As described above, the electromagnetic noise conducted to the heat sink 1 can be returned to the ground line via the base 3 and the gap securing member 5.

That is, in the heat sink 1 according to embodiment 5, the degree of freedom in design can be achieved without being restricted by the wavelength of the electromagnetic wave and the material of the heat dissipating fins 7, and the intensity of the electromagnetic noise can be reduced.

Since the side metal plates 19 are replaced with the upper metal plates 9 and 11, the side metal plates 19 are preferably disposed at positions above the 3 rd end portion 7c and the 4 th end portion 7d of the heat sink 7, respectively.

From the viewpoint of reducing the impedance of the heat sink 7, it is considered that even if the side metal plates 19 are disposed at the central portions of the 3 rd end portion 7c and the 4 th end portion 7d of the heat sink 7, the effect of reducing electromagnetic noise can be obtained. Therefore, the position of the side metal plate 19 is preferably within the range from the center to the upper end of each of the 3 rd end 7c and the 4 th end 7d of the fin 7.

In the heat sink 1 of embodiment 5, the open end sides of the plurality of fins 7 are electrically and physically connected by the side metal plates 19, as in the heat sink 1 of embodiment 1. Thus, even if air flows by a fan (not shown), vibration of the heat sink 7 can be suppressed as an additional effect by the side metal plates 19.

In the embodiments, the conductive member is mainly a plate-shaped member as an example, but the conductive member is not limited to a plate-shaped member as long as the plurality of fins can be electrically connected, and may be a strip-shaped member having conductivity, for example.

The heat sink 1 described in each embodiment and including the upper metal plate or the like as the conductive member can be variously combined as necessary.

The embodiments disclosed herein are illustrative, and not restrictive. The present invention is defined by the claims rather than the above description, and is intended to include all modifications equivalent in meaning and scope to the claims.

Industrial applicability of the invention

The present invention is effectively used for a heat sink having a plurality of fins.

Claims

1. A heat sink, having:

a base portion mounted on a printed circuit board and electrically connected to any one of a signal ground potential, a frame ground potential, and a ground of the printed circuit board; and

a plurality of heat dissipation fins disposed at the base portion at intervals from each other and electrically connected to the base portion,

a part of one of the plurality of heat dissipating fins and a part of another heat dissipating fin are electrically connected to each other through a conductive member at an open end side of the plurality of heat dissipating fins opposite to the side attached to the base,

a plurality of the heat dissipating fins each having a width in a 1 st direction and extending in a 2 nd direction intersecting the 1 st direction,

a plurality of the heat dissipation fins are arranged on the base portion at intervals in a 3 rd direction intersecting the 1 st direction and the 2 nd direction,

the plurality of heat dissipation fins each have:

a 1 st end portion attached to the base portion; and

a 2 nd end portion located on the open end side and opposed to the 1 st end portion with a distance therebetween in the 2 nd direction,

the 2 nd end portion of the one heat radiation fin and the 2 nd end portion of the other heat radiation fin are electrically connected through the conductive member,

the conductive member includes:

a 1 st protrusion provided on the 2 nd end of the one heat radiation fin so as to protrude in the 3 rd direction, and engaging with the other heat radiation fin; and

a 2 nd protrusion provided at the 2 nd end of the other heat radiation fin so as to protrude in the 3 rd direction, and engaging with another heat radiation fin adjacent to the other heat radiation fin,

the 1 st projection is provided with a bridging part, an opening part and an engaging part,

the 2 nd protrusion is provided with a bridge portion, an opening portion, and an engaging portion,

the bridge is configured to bridge between the one and the other heat sinks that are adjacent to each other,

in a state where the one heat radiation fin and the another heat radiation fin are arranged at the base portion, the engaging portion of the 1 st projecting portion is inserted into the opening portion of the 2 nd projecting portion and the one heat radiation fin and the another heat radiation fin are engaged with each other,

the width of the 1 st projecting portion in the 1 st direction is shorter than the width of the one heat dissipating fin in the 1 st direction,

the width of the 2 nd protrusion in the 1 st direction is shorter than the width of the other heat dissipating fin in the 1 st direction,

two of the 1 st protrusions are disposed on the one heat dissipation fin at a distance in the 1 st direction.

2. The heat sink of claim 1,

the heat sink includes a space holding member attached to the base portion and holding a space between the base portion and the printed circuit board,

the plurality of heat dissipation fins are electrically connected to any one of the signal ground potential, the frame ground potential, and the ground line of the printed circuit board via the base portion and the spacer.

3. The heat sink according to claim 1,

a plurality of the heat dissipation fins are formed of the same material.

4. The heat sink according to claim 1,

the plurality of radiating fins have the same size.