JPH0329183B2 - - Google Patents

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to a semiconductor device (hereinafter referred to as "laminated body") in which a stacked body in which flat semiconductor elements and heat dissipation fins are alternately stacked is supported by applying pressure between a pair of support plates. The present invention relates to a semiconductor stack (hereinafter referred to as "semiconductor stack"), and particularly to a structure of a semiconductor stack that facilitates assembly and replacement of assembled flat semiconductor elements in the event of a failure or the like.

[Prior art]

FIG. 4 shows an example of a conventional semiconductor stack.

In the figure, 1a and 1b are support plates, 2 are bolts inserted into the four corners between the support plates 1a and 1b,
3 is a disc spring inserted into one end of this bolt 2;
5a and 5b are stands for fixing to other external members such as a frame, and 6 and 7 are nut locks and nuts inserted through both ends of the bolt 2. Furthermore, flat semiconductor elements 8 and heat dissipation fins 9 are alternately stacked between the support plates 1a and 1b.
Insulating spacers 10a and 10b are arranged at both ends, and a ball 11 is placed on one insulating spacer 10b side.
and an alignment device 13 consisting of ball receiving plates 12a and 12b arranged oppositely with this ball 11 in between.
It is equipped with

When assembling the semiconductor stack having the above structure, it is generally carried out in the following order.

One end of the four bolts 2 is inserted into the through holes provided at the four corners of the support plate 1b, and a predetermined number of disc springs 3, a disc spring retaining plate 4, a nut lock 6, and a nut 7 are sequentially inserted into one end of each of the bolts 2. After inserting the nut 7 and screwing it to an appropriate position, align the claw of the nut lock 6 with one side of the nut 7 and raise it up.

Place the above intermediate assembly on a workbench so that the support plate 1b is on the bottom surface and the four bolts 2 are vertical.

The ball receiving plate 12b, ball 11, and ball receiving plate 12a of the aligning device 13 are stacked one after another, then the insulating spacers 10b, the heat dissipation fins 9, and the flat semiconductor element 8 are stacked alternately, and the insulating spacer 10a is stacked on top. , a support plate 1a, a nut lock 6 and a nut 7 are attached to the upper ends of the four bolts 2.
Insert.

Next, a predetermined pressurizing force is applied from the outside of the support plate 1a against the elastic force of the disc spring 3 using a predetermined pressurizing machine such as a hydraulic press, and the nut 7 is screwed in by the amount that the disc spring 3 is deflected. Raise the claws of Natsutrotsuku 6.

After the semiconductor stack assembled at the factory according to the above procedure is assembled into the specified equipment, the device into which the semiconductor stack is installed may be damaged due to breakage during actual operation or other accidents. may need to be replaced at the installation site.

In such a case, it is necessary to reassemble the semiconductor stack according to the following procedure. In many cases, a pressure press to apply a specified pressure force is not available at the installation site, so first, accurately measure the amount of deflection δ ₀ of the disc spring 3 using a measuring instrument such as a caliper or gap gauge. I'll keep it.

Next, loosen the four nuts 7 on either side of the support plate 1a or 1b. The amount of loosening of the nut 7 at this time is the amount necessary and sufficient to take out the flat semiconductor element 8. In other words, the amount that the nut 7 is loosened is enough to take out the flat semiconductor element 8. A center pin for positioning that protrudes by about 5 mm is provided, but the center pin is loosened enough to allow the flat semiconductor element 8 to be taken out without getting caught on the heat dissipation fins 9.

Next, a flat semiconductor element 8 that should be replaced due to failure etc.
After taking it out, a new flat semiconductor element 8 is replaced, and the nut 7 is tightened again, applying the measuring instrument to the nut 7 until the previously measured deflection amount δ ₀ is reached.

However, the semiconductor stack having the above structure is inconvenient, especially when replacing flat semiconductor devices at an installation site.

In other words, in order to maintain the specified pressure force at the installation site, the amount of deflection must be accurately measured during disassembly and reassembly, and this work is complicated, and a small error in measuring the deflection amount can greatly increase the pressure force. In addition, if the nut is loosened, elements other than the flat semiconductor element that should be replaced are likely to fall out, requiring more labor and time than necessary for the assembly process. In order to maintain the pressure, a pressure press is sometimes brought to the device replacement site, but in this case, it is heavy and inconvenient to transport and other aspects, and it is also difficult to handle the semiconductor stack when replacing flat semiconductor devices. itself from an external member such as the frame of the installation device to the stand 5a,
There were inconveniences such as having to remove the mounting screws of 5b each time.

[Summary of the invention]

The present invention has been made based on the above-mentioned circumstances, and the main bolt that regulates the distance between the pair of support plates remains fixed without being loosened even when replacing a flat semiconductor element after assembly, and is provided separately. It is possible to maintain a predetermined pressing force after reassembly by adjusting the secondary bolt, and by providing an alignment device that is biased in the axial direction, the stacked structure of the flat semiconductor element and the heat dissipation fin can be adjusted to an appropriate level. To provide a semiconductor stack which prevents parts other than a flat semiconductor element to be inadvertently dropped to the outside even when a sub-bolt is loosened by applying a strong pressing force.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3, in which the same parts as in FIG. 4 showing the conventional example are given the same reference numerals.

A through hole 14 is formed approximately in the center of one of the support plates arranged to face each other in the axial direction, for example, on the side of the support plate 1b.
is provided, and an alignment device 130 is disposed within this through hole 14. As shown in the enlarged cross-sectional view of FIG.
31, two alignment members 13 having convex surfaces 132
3, 134 and an elastic body, for example, a coil spring 1, which is interposed between the centering members 133, 134 and biases the members 133, 134 in a direction away from each other.
35, and these centering members 133, 134 are coupled at their centers by a center pin 136 so that the centering member 134 can move in the axial direction.

The rear end of the center pin 136 protruding from one end of the alignment member 134 is inserted into the center hole 16 of the pressure plate 15 disposed outside the support plate 1b and fixed by the simple fixing means 17. In addition, alignment member 133
An initial positioning mark M ₁ and a specified pressing force display mark M ₂ , which will be described later, are attached to the outer periphery. In addition,
These marks M ₁ and M ₂ are displayed by painting,
Any method such as marking or grooves may be used.

The pressure plate 15 is provided with through holes 15a and 15b at both ends, respectively.
A secondary bolt 18 for tightening is inserted through b, and this bolt 18 is configured to be screwed into the support plate 1b.

Next, the assembly order of the semiconductor stack according to the present invention having the above structure will be explained.

After inserting one end of four main bolts 2 into the through holes provided at the four corners of the support plate 1a, a nut lock 6 and a nut 7 are fixed to one end of the bolts 2.

After placing the above assembly on the workbench so that the four main bolts 2 are vertical, a plurality of large-diameter disc springs 19 and insulating spacers 10 are placed on the support plate 1a.
a. The heat dissipation fins 9 and the flat semiconductor element 8 are stacked in a predetermined direction and order.

Finally, after inserting the other support plate 1b through the main bolt 2, attach the nut lock 6 to one end of this bolt 2.
through the nut 7.

Insert the alignment device 130 into the through hole 14 of the support plate 1b, position the pressure plate 15 on the outside of the support plate 1b, and insert the secondary bolts 18 into the through holes 15a, 15b of the pressure plate 15 (see FIG. 2). ) to the support plate 1b to the extent that it can be tightened by hand.

Next, the pressure plate 15 is pressed in the axial direction of the semiconductor stack against the spring force of the coil spring 135 built into the alignment device 130, thereby aligning the alignment members 133, 134.
The concave surface 131 and convex surface 132 of are brought into contact. Note that the spring constant and number of turns of the coil spring 135 built into the centering device 130 are designed in accordance with a predetermined pressing force required at the time of initial setting to pressurize the stacked body.

That is, when the alignment member 134 is pressed against the coil spring 135 and its convex surface 132 contacts the concave surface 131 of the alignment member 133, a certain pressing force is applied to the laminate. In this state, tighten the nuts 7 of the four main bolts 2 and the two sub bolts 18.
Tighten.

In such a case, the nut 7 of the main bolt 2 is tightened by the nut lock 6 for final tightening. On the other hand, the secondary bolt 18 is temporarily tightened, but in the above embodiment, the initial positioning mark M ₁ is attached to the outer periphery of the alignment member 133, so this mark M ₁ supports the temporary tightening. The position coincides with the inner edge of the plate 1b.

Next, a specified pressing force should be applied to the laminate.
Tighten the secondary bolt 18. That is, by tightening the secondary bolt 18 using a tool such as a spanner, the end face of the alignment member 133 presses the laminate, and the end face of the insulating spacer 10a arranged at the end of the laminate is pressed against the plate. Deflect the spring 19. At that time, the amount of deflection δ ₁ is adjusted by relying on the specified pressure display mark M ₂ attached to the alignment member 133, and the alignment member 133 is moved in the axial direction to the position of this display mark M ₂ . By tightening the secondary bolt 18, a specified pressing force will be applied to the laminate.

After completing the tightening of the sub-bolt 18 at the position where the above-mentioned display mark _M2 and the inner edge of the support plate 1b coincide with each other, the sub-bolt 18 is fixed by raising the nail of the nuts lock (not shown).

As described above, the assembly of the semiconductor stack according to the present invention is completed.

In addition, the initial alignment mark M ₁ and the specified pressure display mark M ₂ attached to the alignment member 133
For example, as shown in FIG.
A disc spring positioning member 20 is provided between the disc spring 19 and the disc spring 19, and one end of the disc spring positioning member 20 is inserted into the through hole 1c of the support plate 1a and moves in the axial direction of the semiconductor stack in response to the pressing force of the laminate. 1a
By specifying the amount of protrusion from the marks M ₁ and M ₂
It can be replaced with

That is, the position where one end surface of the positioning member 20 coincides with the outer edge of the support plate 1a may be, for example, the initial setting position, and the position where the member 20 protrudes by an amount H may be the position where the specified pressure is applied.

Furthermore, the initial alignment mark M ₁ and the prescribed pressure display mark M ₂ are not limited to the alignment member 133 side, but can also be provided on the alignment member 134 side.

Now, in the case where it is necessary to replace the flat semiconductor element 8 in the semiconductor stack described above after it has been installed in a predetermined device, the following procedure is followed.

When the two sub-bolts 8 of the semiconductor stack are loosened, the restoring force of the disc spring 19 pushes the stack to the right in the figure and pushes the alignment member 133, which moves to the right for initial positioning. It is temporarily stopped at a position where the mark _M1 and the inner edge of the support plate 1b coincide.

Next, when the sub bolt 18 is further loosened,
The alignment members 133 and 134 are gradually separated by the spring force of the coil spring 135, but the spacing is slightly larger than the amount of protrusion of the center pin of the flat semiconductor element 8, that is, in this embodiment, the amount of protrusion of the center pin is Since the distance is about 5 mm, loosen the sub bolt 18 until a slightly larger distance of about 6 to 10 mm is formed.

In the above state, a predetermined pressing force is applied to the stacked body by the spring force of the coil spring 135 disposed within the alignment device 130.

Next, the heat radiation fins 9 on both sides of the flat semiconductor element 8 to be replaced are pushed outward against the spring force of the coil spring 135, and the element 8 is taken out and a new flat semiconductor element 8 is inserted.

Tighten the auxiliary bolt 18 again and press the disc spring 19 through the pressure plate 15, alignment device 130, insulating spacer 10b, the laminate of the heat dissipation fin 9 and flat element 8, and the insulating spacer 10a to display the specified pressing force. Deflect by a specified amount based on Yak M ₂ etc. to apply specified pressure.

〔Effect of the invention〕

Since the present invention is constructed as described above, flat semiconductor elements having a malfunction can be easily replaced at the installation site of a semiconductor stack. In other words, the pressure applied to the laminate is made proportional to the displacement due to the tightening of the sub-bolts, and this can be visually confirmed by means of display marks, etc., so there is no need to use other measuring instruments, gauges, etc., or a pressure press, etc. To accurately and easily maintain a specified pressing force without using it, and also to eliminate the inconvenience of transporting a heavy pressing press to an installation site. In addition, when replacing a flat semiconductor element, a predetermined pressure force in the axial direction is applied to the laminate by the coil spring of the alignment device. Components do not fall off from the assembly, thus reducing the labor and time required for reassembly.

[Brief explanation of drawings]

FIG. 1 shows a semiconductor stack showing an embodiment of the present invention, in which FIG. A is a plan view thereof, FIG. B is a front view thereof, FIG. C is a right side view thereof, and FIG. Figure 3 is an enlarged cross-sectional view of the aligning device, with Figure A being an enlarged cross-sectional view with no pressure applied, Figure B being an enlarged cross-sectional view with a predetermined pressure being applied, and Figure 3 being an enlarged cross-sectional view with a predetermined pressure applied. FIG. 4 is a partially cross-sectional front view for explaining another embodiment of the pressure display section, and FIG. 4 is a front view showing an example of a conventional semiconductor stack. 1a, 1b...Support plate, 2...Main bolt, 8...
... Flat semiconductor element, 9 ... Heat dissipation fin, 10a,
10b... Insulating spacer, 15... Pressure plate, 18
... Width bolt, 19 ... Belleville spring, 130 ... Alignment device, 131 ... Concave surface, 132 ... Convex surface, 13
3,134... Aligning member, 135... Coil spring.

Claims (1)

[Claims] 1. In a semiconductor device in which a main bolt is inserted between a pair of support plates and a laminate of a flat semiconductor element and a heat dissipation fin is interposed between the support plates, a concave surface and a convex surface having mutually complementary shapes are arranged opposite to each other. Grooves are provided in the outer peripheries of the two alignment members to face each other, and a coil spring is built in the grooves, and a pressure plate that comes into contact with the back surface of one of the alignment members is moved by a center pin to the centering member. an alignment device temporarily fixed to the support plate, and a secondary bolt for applying a predetermined pressing force to the laminate of the flat semiconductor element and the heat dissipation fin through the alignment device, on one side of the support plate. A semiconductor device characterized in that: