JP4687357B2 - Heat sink device - Google Patents

Description

  The present invention relates to a heat sink device provided with a mechanism for adjusting a gap between a semiconductor element and a radiator to a constant value when a radiator is attached to the semiconductor element.

As shown in FIG. 4, the heat sink in the related art has a column 113 having at least a height dimension of the semiconductor element 112 mounted on the printed circuit board 111 with respect to the semiconductor element 112 mounted on the printed circuit board 111. It is well known that the radiator 114 having the above is attached by filling the heat radiation sheet 115 or the heat radiation grease from the upper part of the semiconductor element 112 to the top of the semiconductor element 112.
There are two methods for dealing with the case where the height dimensions of the semiconductor elements 112 mounted on the printed circuit board 111 are different. One method is to compress the heat dissipation sheet 115 to absorb the difference in height. The other method is to make the height of the support 113 different to match the height of the semiconductor element 112.

  FIG. 5 shows a state in which the heat sink 114 is attached by changing the amount of compression of the compression sheet 115. FIG. 5A shows that the semiconductor element 112 is low in height and the heat radiation sheet 115 is compressed. FIG. 5 (B) shows a state in which the height of the semiconductor element 112 is higher than that shown in FIG. 5 (A), and the heat dissipation sheet 115 is more compressed. FIG. 5C shows a state in which the height of the semiconductor element 112 is high and the heat dissipation sheet 115 is compressed to the limit to absorb the difference in height.

6 shows a state in which the radiator 114 is attached with the height of the support 113 adjusted to the height of the semiconductor element 112. FIG. 6A shows the height of the semiconductor element 112. FIG. This shows a state in which the support 113A is set low with respect to a relatively low value. In FIG. 6B, the height dimension of the semiconductor element 112 is higher than the height of the semiconductor element 112 shown in FIG. 6A, and the height of the column 113B is set higher. Therefore, the radiator 114 is provided at a position higher than the radiator 114 illustrated in FIG.
In FIG. 6C, the height dimension of the semiconductor element 112 is higher than the height of the semiconductor element 112 shown in FIG. 6B, and the height of the column 113C is set higher.
JP-A-7-161886 (pages 2 to 3 and FIG. 1)

However, in the method of compressing the heat dissipation sheet shown in FIG. 5 and absorbing the difference in height as described in the prior art, even if the same semiconductor element is attached to the same printed circuit board, the outer shape of the element The size of the gap between the semiconductor element and the heatsink is not constant due to the dimensional tolerances and the lift and inclination of the soldering. Although heat radiation grease or a heat radiation sheet is sandwiched as a flexible heat transfer material that compresses and deforms to fill the gap, the heat resistance of the heat transfer member is proportional to the thickness thereof, and the heat resistance value also changes for each semiconductor element. In particular, when a large dimensional tolerance is required for the element outline and soldering lift, the heat resistance value of the heat dissipation member also changes in proportion to that, and even if the same semiconductor element is operated under the same conditions, heat dissipation The temperature varies greatly from device to device due to the difference in ability.
In addition, when the dimensional tolerance of the semiconductor element outline is large, the design center side of the gap itself is designed to be large as a margin so that the element is not crushed by the heatsink, but the back of the element is as low as possible. In some cases, the distance between the element and the heat sink becomes longer, which is disadvantageous in terms of heat transfer.
On the other hand, in the method shown in FIG. 6 in which the height of the column is different and matched to the height of the semiconductor element, the length of the column is used to make the thickness of the heat radiation sheet and grease constant by using the mechanism. There is also a method of changing the height to match the height of each semiconductor element. However, it is necessary to prepare many types of pillars with different lengths according to the height distribution of the semiconductor elements, and when attaching the pillars, it is troublesome to measure the height of all the semiconductor elements every time. There is a problem that it takes.

  Therefore, there is a problem that must be solved to realize a structure in which the interval between the semiconductor element and the radiator can be finely adjusted according to the height of the semiconductor element without using a complicated mechanism.

  In order to solve the above problems, the heat sink device of the present invention is configured as follows.

(1) The heat sink device
In a heat sink device in which at least two spacers having a height dimension of the semiconductor element are attached and fixed to a printed circuit board on which the semiconductor element is mounted, and a radiator is attached via the two attached and fixed spacers.
The two spacers each have an inclined surface whose upper surface is inclined in the same direction, and a screw engagement recess for engaging a screw with the inclined surface,
The radiator has an inclined surface whose bottom surfaces at both ends are inclined at the same angle in the same direction as the inclined surface provided on the spacer, and an adjustment hole having a long hole in the direction along the inclined surface,
The lower surface of the radiator and the semiconductor are adjusted by moving the radiator in the horizontal direction by bringing the inclined surface of the radiator into contact with the inclined surface of the spacer and moving the radiator in the horizontal direction. By maintaining the state where the gap with the upper surface of the element is maintained constant, and by assembling the radiator on the semiconductor element by locking the screw engaging recess with the screw fitted in the adjustment hole is there.

According to the present invention, even if the height of the semiconductor element mounted on the printed circuit board is different by forming both surfaces of the portion where the radiator and the spacer are in contact with each other in the same direction, By moving the radiator horizontally according to the height or by moving the spacer in the horizontal direction, the gap between the top surface of the semiconductor element and the radiator can be always kept constant.
In addition, the main components are only a combination of a radiator having an inclination θ on the bottom surface and a spacer having an inclination θ on the upper surface, and the gap between the radiator and the semiconductor element can be kept constant with a simple mechanism. Can do.

Next, a heat sink device according to a first embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the heat sink device of the present invention includes a radiator 14 in which rectangular heat sinks 15 are aligned, a semiconductor element 12 mounted on a printed circuit board 11, and the semiconductor element 12. Two spacers 13 arranged in parallel so as to be sandwiched, and a heat dissipation sheet 15 having a small amount of compressive deformation are provided on the upper surface of the semiconductor element 12.

  The radiator 14 has an inclined surface 16 whose bottom surfaces at both ends are inclined in the same direction by an angle θ, and a long hole along the inclined surface 16 penetrating upward is formed at a predetermined position of the inclined surface 16. The adjustment hole 17 is provided. This adjustment hole 17 has a structure provided in four locations on the four sides of the radiator 14 having a quadrangular shape in the embodiment, and all of the adjustment holes 17 are elongated in the direction along the inclined surface 16. A screw 20 is inserted into the adjustment hole 17 and screwed into the spacer 13 with the screw 20 to maintain the gap between the radiator 14 and the semiconductor element 12 at a constant value.

  The spacer 13 is formed in an elongated rectangular parallelepiped shape having at least the height dimension of the semiconductor element 12 mounted on the printed circuit board 11, and is fixed to the printed circuit board 11. The upper surface of the spacer 13 radiates heat with respect to the horizontal plane. In the same manner as the angle θ of the inclined surface 16 of the vessel 14, it is formed on an inclined surface 18 having an angle θ, and has a screw engaging recess 19 that engages a screw 20 at both ends in the longitudinal direction. ing.

  As described above, the bottom surface of the radiator 14 is the inclined surface 16, the upper surface of the spacer 13 is also the inclined surface 18 having the same inclination angle, the inclined surfaces 16 and 18 are brought into contact with each other, and the radiator 14 is horizontally aligned. Is finely adjusted in the vertical direction. As a result, a state in which the gap between the lower surface of the radiator 14 and the upper surface of the semiconductor element 12 is kept constant is maintained and the screw 20 fitted in the adjustment hole 17 is engaged with the screw engaging recess 19. The radiator 14 can be assembled on the semiconductor element 12.

  2 shows that when the height of the semiconductor element 12 mounted on the printed circuit board 11 is different, the heat sink 14 is moved in the horizontal direction with the same amount of compressive deformation of the heat radiating sheet 15. 2 shows a state in which the gap between the upper surface of the semiconductor element 12 and the lower surface of the radiator 14 is kept constant by finely adjusting the radiator 14 in the vertical direction, as shown in FIG. The semiconductor element 12 has a low height, and shows a state in which the radiator 14 is moved to the limit in the horizontal direction and fixed with the screw 20 fitted in the adjustment hole 17 in the lowest height state. is there. 2B, the height of the semiconductor element 12 is higher than that shown in FIG. 2A, and the radiator 14 is moved in the horizontal direction so as to match the height of the adjustment hole 17. The state fixed with the screw 20 fitted to the substantially intermediate position is shown. 2 (C) is higher than the height of the semiconductor element 12 shown in FIG. 2 (B). In order to align the radiator 14 with it, it is moved in the horizontal direction and leftward in the adjustment hole 17 diagram. The state fixed with the screw 20 fitted to the position is shown.

  In the embodiment, the spacer 13 is fixed on the printed circuit board 11 and the radiator 15 can be moved in the horizontal direction to make fine adjustments in the vertical direction. However, the spacer is not limited to this. If 13 is configured to be able to move horizontally on the printed circuit board 11, it is not necessary to move the radiator 15 in the horizontal direction. In this way, the positional relationship of the radiator 15 can be determined in advance, making it easy to design and minimizing the area occupied by the parts.

  Further, the heat dissipation sheet 15 is not limited to this, and may be a heat dissipation grease having a low viscosity, for example. If a heat dissipation grease having a low viscosity or a heat dissipation sheet 15 having a small amount of compressive deformation is used, the heatsink 14 is shifted and installed at a position where the semiconductor element 12 surface or the heatsink sheet 15 upper surface and the heatsink 14 bottom surface are attached to each other Even if the height differs from one semiconductor element 12 to another, the distance between the radiator 14 and the semiconductor element 12 can be a constant value (sheet thickness).

  Next, a heat sink device according to a second embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 3, the heat sink device according to the second embodiment includes a radiator 14A in which rectangular heat sinks 15 are aligned, a semiconductor element 12 mounted on a printed circuit board 11, and the semiconductor element. Two spacers 13 </ b> A arranged so as to sandwich 12 and a heat dissipation sheet 15 having a small amount of compressive deformation are provided on the upper surface of the semiconductor element 12.
This heat radiating sheet 15 is not limited to this, and may be a heat radiating grease having a low viscosity, for example.

The radiator 14A is formed with inclined surfaces 16A and 16B which are inclined at an angle θ in a symmetrical direction having an inverted C-shaped inclination on the bottom surfaces of both ends, and at predetermined positions on the inclined surfaces 16A and 16B. Has a structure with an adjustment hole 17A penetrating in the upper part.
The spacer 13A has at least the height dimension of the semiconductor element 12 mounted on the printed circuit board 11, and can move horizontally on the printed circuit board 11. The top surface of the spacer 13A is a horizontal surface of the radiator 14A. The hollow portion 22 formed on the inclined surface 18A having the inclination of the angle θ similar to the angle θ of the inclined surface 16A or 16B and passing through the screw 20A is moved in the horizontal direction with the screw 20A passing therethrough. The size of the radiator 14A can be finely adjusted in the vertical direction.

As described above, the bottom surface of the radiator 14 is formed as symmetrical inclined surfaces 16A and 16B, and the upper surface of the spacer 13A is also formed as an inclined surface 18A having the same inclination angle, so that the spacer 13A can be adjusted in accordance with the height of the semiconductor element 12. The radiator 14 </ b> A is moved in the vertical direction by moving horizontally on the printed circuit board 11, and fine adjustment is performed, and the position adjusted with the screw 20 </ b> A and the nut 21 may be fixed.
Thus, since it is not necessary to move the radiator 14A in the horizontal direction, it is not necessary to change the installation position, and the design can be facilitated and the area occupied by the components can be minimized. .

Both surfaces of the part where the heatsink and the spacer are in contact are formed on the inclined surface inclined in the same direction, and the heatsink is moved horizontally or the spacer is moved horizontally to finely adjust the height of the heatsink. Due to the structure, even if the height of the semiconductor element mounted on the printed circuit board is different, it can be mounted in a state where the gap between the top surface of the semiconductor element and the radiator is always kept constant according to the height. Provided is a heat sink device that can be used.

It is a perspective view of each component which comprises the heat sink apparatus of 1st Example of this invention. It is explanatory drawing which showed a mode that a heat radiator was moved to a horizontal direction based on the height of a semiconductor element, and heat radiator itself was adjusted to the height direction. Explanation of the heat sink device of the second embodiment of the present invention, showing how to adjust the radiator itself in the height direction by moving the spacer in the horizontal direction without moving the radiator based on the height of the semiconductor element. FIG. It is a perspective view of each component which comprises the heat sink in a prior art. It is explanatory drawing which showed the compression condition of the thermal radiation sheet according to the height of the semiconductor element in a prior art. It is explanatory drawing which shows a mode that the spacer (support | pillar) from which height differs according to the height of the semiconductor element in a prior art is employ | adopted.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Printed circuit board 12 Semiconductor element 13 Spacer 14 Radiator 15 Radiation sheet 16 Inclination surface 16A Inclination surface 16B Inclination surface 17 Adjustment hole 17A Adjustment hole 18 Inclination surface 18A Inclination surface 19 Screw engagement recessed part 20 Screw 20A Screw 21 Nut 22 Hollow part

Claims (1)

In a heat sink device in which at least two spacers having a height dimension of the semiconductor element are attached and fixed to a printed circuit board on which the semiconductor element is mounted, and a radiator is attached via the two attached and fixed spacers.
  The two spacers each have an inclined surface whose upper surface is inclined in the same direction, and a screw engagement recess for engaging a screw with the inclined surface,
  The radiator has an inclined surface whose bottom surfaces at both ends are inclined at the same angle in the same direction as the inclined surface provided on the spacer, and an adjustment hole having a long hole in the direction along the inclined surface,
  The lower surface of the radiator and the semiconductor are adjusted by moving the radiator in the horizontal direction by bringing the inclined surface of the radiator into contact with the inclined surface of the spacer and moving the radiator in the horizontal direction. Maintaining a state where the gap with the upper surface of the element is kept constant, and assembling the radiator on the semiconductor element by locking the screw engaging recess with a screw fitted in the adjustment hole. A heat sink device characterized.

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