JP2556435Y2 - Ground structure of heat sink - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grounding structure of a heat sink, for example, a heat-generating electronic component mounted on a printed circuit board incorporated in an electric or electronic device, for example, an IC or TR.
The present invention relates to a grounding structure of a radiator plate for mounting a radiator plate for holding a heating element on a printed circuit board and connecting to a ground.

[0002]

2. Description of the Related Art Heretofore, as a grounding structure of a radiator plate, since a radiator plate is generally made of aluminum and it is difficult to solder it, a grounding structure 11 described below has been adopted. For example, FIG.
As shown in FIG. 3, a heat radiating plate 13 holding an IC 12 that generates heat
Since an aluminum plate is used so that the heat and the radiation of the IC 12 are good, it is difficult to directly connect the printed circuit board 15 with the solder. For this reason, a rectangular through hole 15a is usually provided in the printed circuit board 15, and a mounting foot 13 that penetrates the through hole 15a is formed below the heat sink 13.
a is provided. The radiator plate 13 allows the mounting feet 13a to penetrate below the through holes 15a of the printed circuit board 15, and furthermore, the lower part of the mounting feet 13a is pliers or the like below the printed circuit board 15 in the longitudinal direction of the through holes 15a. The printed circuit board 15 is fixed between the lower portion 13b of the radiator plate 13 and the lower portion of the mounting foot 13a by being deformed substantially at a right angle by the jig.

The heat radiation plate 13 must be grounded in order not to generate noise in the line.
Because it is, the solder can not be used directly, usually with a lead wire 16, the heat radiating plate 13 is fixed by screws 17,
The ends of the lead wires 16 are fixed to the ground of the printed circuit board 15 with solder 18, and the heat sink 13 is connected to the ground to be grounded.

[0004]

2. Description of the Related Art As an improved technique described above, an electric connection between a heat sink and a ground of a printed circuit board is disclosed in
2995, a conductive elastic member was used instead of a lead wire, and the elastic member was elastically held by a facing piece of a heat sink. However, in order to maintain the conductive property for a long time, Therefore, it is necessary to use an elastic member such as phosphor bronze which does not easily rust.In addition, since the electrical resistance by elastic retention is unstable and tends to increase, a member with a large contact area to compensate for it It would be expensive to use, and in view of the complexity of the processing steps, it was inevitable to provide opposing projections on the heat sink or to make the shape of the elastic member special. .

[0005]

Therefore, there is a need for a grounding structure for a heat sink that can use an inexpensive inelastic member and that can stably maintain electrical resistance by performing electrical connection by mechanical pressure welding. Was.

Further, in order to simplify the processing steps, it is desired that the heat sink be capable of processing the shape of the grounding member by a general processing step without requiring any special processing steps other than the mounting portion. .

[0007]

In order to solve the above-mentioned problems, the present invention provides a grounding structure of a radiator plate in which a radiator plate holding a heating element is erected on a printed board and connected to the ground of the printed board. A mounting portion is provided on the heat sink, protruding to the back side through the through hole of the printed board,
A grounding member is disposed on the surface of the printed circuit board so as to be sandwiched between the heat sink and the printed circuit board. The heat sink and the grounding body are electrically stabilized by a pressing force generated by deforming the plurality of mounting portions to mechanically hold the heat sink to the printed circuit board at the side. And a grounding structure for the heat sink.

[0008]

In the grounding structure of the heat sink of the present invention, the grounding body made of a conductive member can be dipped and soldered at the same time as the components on the other printed circuit boards. The pressing force when the mounting portion is deformed later is stably maintained at a low value in order to maintain the state in which the heat sink is pressed against the grounding body.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall exploded perspective view showing an embodiment of a grounding structure of a heat sink according to the present invention. FIG. 2 is an enlarged view of the mounting piece and the grounding body. In FIG. 2, the grounding body 2 is connected to the ground pattern 7 on the back surface of the printed circuit board 3. First, the configuration will be described. 1 and 2, 100
Is a grounding structure of the heat radiating plate, grounding structure 100 of the heat sink and the heat radiating plate 1 made of aluminum, disposed on the printed circuit board 3 having a thickness t ₁ of about 1.6mm conductive members immediately below the heat radiating plate 1 , For example, a copper-plated grounding body 2. The grounding body 2 is a foot 2 whose both ends are bent downward.
As shown in FIG. 3, the printed circuit board 3 is disposed at a position connectable to the ground 7 of the printed circuit board 3, and the foot 2 a passes through a through hole 3 a formed in the printed circuit board 3.
And is connected to ground 7 by solder 8. The heat radiating plate 1 has a crooked shape so that it can be stably erected, and an IC 4 that generates a large amount of heat is fixed to a side wall by a screw 5. The heat radiating plate 1 is disposed so that the pressure contact portion 1a at the lower end thereof intersects and contacts the upper surface 2b of the grounding body 2, and penetrates through the through hole 3b formed in the printed circuit board 3 at the lower side to be below the printed circuit board 3. It has a protruding mounting portion 1b. The mounting portion 1b includes a main body 1A of the heat sink 1, a narrow neck portion 1c extending downward from the main body 1A, and a neck portion 1c.
The shoulder portion 1d has a wider width on the lower side and a torso portion 1e having substantially the same width further below the shoulder portion 1d. The neck portion 1c, the shoulder portion 1d, and the torso portion 1e are integrally formed. ing. The length t ₂ of the downward neck portion 1c is less than the thickness t ₁ of the printed circuit board 3. As shown in FIG. 3, the mounting portion 1b can be deformed in the direction of arrow A with respect to the main body 1, and this deformation allows the upper surface of the shoulder portion 1d to engage with the lower edge of the printed circuit board 3 to form a heat sink. Is fixed on the printed circuit board 3. Next, the operation will be described. The foot 2a of the grounding body 2 is inserted into the through hole 3a of the printed circuit board 3, and is connected to a predetermined position of the printed circuit board 3 at the same time with other electronic components such as ICs and Trs by soldering or the like.
At this time, the foot 2a is connected to the ground 7 of the printed circuit board 3. Next, the mounting portion 1a of the heat radiating plate 1 in which the IC 4 is fixed by the screw 5 is inserted into the through hole 3b on the printed circuit board 3, and then the trunk portion 1c of the mounting portion 1a protruding downward from the printed circuit board 3. Is rotated about 90 °. At this time ,
Since the thickness t ₁ > the thickness t ₂ , the torso portion 1 e enters the lower side of the printed circuit board 3 while the mounting portion 1 b is deformed, and the shoulder portion 1
d largely deforms and engages with the lower edge of the printed circuit board 3.
Since the width of the shoulder portion 1d is larger at the lower side and the upper edge is inclined, as the deformation becomes larger, a force for pulling the main body 1A downward acts, and the main body 1A is fixed to the printed circuit board 3. At this time, the pressure contact portion 1a of the heat sink 1 is pressed against the upper surface 2a of the grounding body 2 and is electrically connected. Therefore, the heat radiating plate 1 can be fixed to the printed circuit board 3 only by a simple operation of rotating and deforming the mounting portion 1a by about 90 °. In this case, it is preferable that the grounding body 2 is slightly raised from the upper surface of the printed circuit board 3. In the present embodiment, there are two mounting pieces 1a for the heat radiator, but it is preferable to provide several suitable places together with the grounded body 2 according to the size of the heat radiator plate 1. Further, the cutout shape of the mounting piece 1a is not limited to this, but may be any as long as it generates a force for pulling the main body 1A downward, thereby ensuring the grounding.

[0010]

[Effects of the Invention] As described above, according to the present invention,
The earth plate provided on the grounding body can be soldered at the time of dipping together with other electronic components, so that the number of steps can be reduced. The radiator plate has both functions of mounting and pressure contact, and the simple operation of bending the mounting portion exerts a force on the radiator plate to ensure pressure contact with the grounded body. Also,
Skill is not required for the mounting work, so that productivity can be improved and manufacturing costs can be reduced by reducing the number of steps.

[Brief description of the drawings]

FIG. 1 is an overall exploded view showing one embodiment of a grounding structure of a heat sink of the present invention.

FIG. 2 is an enlarged view showing a pressure contact state between a heat sink and a grounded body of the embodiment shown in FIG.

FIG. 3 is a top view showing a state where a mounting portion of the embodiment shown in FIG. 1 is bent.

FIG. 4 is an explanatory view of a conventional ground structure of a heat sink.

[Explanation of symbols]

1 radiating plate 1a contact portion 1b attachment portion 2 the grounding member 3 printed circuit board 4 shots Netsutai 5 bis 6 leads 7 earth pattern

Claims (1)

(57) [Scope of request for utility model registration] 1. A grounding structure for a heat radiating plate, wherein a heat radiating plate holding a heating element is erected on a printed circuit board and connected to the ground of the printed circuit board. A mounting part protruding to the side is provided,
A grounding member is disposed on the surface of the printed circuit board so as to be sandwiched between the heat sink and the printed circuit board. The heat sink and the grounding body are electrically stabilized by a pressing force generated by deforming the plurality of mounting portions to mechanically hold the heat sink to the printed circuit board at the side. A grounding structure for a heat sink, characterized by being connected to a heat sink.