JPH0432758Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a resin-sealed package, particularly its structure.

<Summary of the invention> The present invention has a screw fixing part for an external device on the outside of the lower part of the case, a body to be sealed is placed in the bottom opening inside the case, and a resin is applied to the case so as to cover the body to be sealed. In a resin-sealed package, for example, an internal casting resin is injected and solidified so as to cover the object to be sealed, and then the internal casting resin is covered with a final sealing resin. In order to improve the joint strength against the stress that tends to expand the side wall of the case outward at the joint surface of the case and the resin injected into the case when screwing it to the A hook portion that protrudes inward and bends downward is integrally provided, and the hook portion is covered with the sealing resin and buried.

<Conventional technology> The prior art will be explained below with reference to the drawings.

FIG. 2 is a sectional view of a resin-sealed package that is an example of a conventional power transistor module.

In the conventional resin-sealed package, as shown in FIG. 2, an internal circuit board 3 and internal circuit components 4 are arranged on a heat dissipation board 2 that forms the bottom of a case 1, and device outputs connected to these internal circuit components 4 are arranged. terminal 5
protrudes from the opening of the case 1. Inside the case 1, in order to protect the internal circuit components 4, an internal casting resin 6 such as silicone is first injected and solidified so as to cover the internal circuit board 3 and internal circuit components 4, and then the internal casting resin 6 is A final sealing resin 7 such as epoxy is injected and solidified so as to cover it.

Note that 1a is a through hole for fixing screws when assembling into a device.

<Problems to be solved by the invention> The problem here is that in the resin-sealed package constructed as described above, the inner surface of the side wall of the case 1 is flat, and the resins 6 and 7 are Although the injected, hardened, and bonded resin retains a certain degree of strength, it has the disadvantage that interfacial peeling is likely to occur at the bonding surface between the case 1 and the resins 6 and 7 injected into the case 1 due to external stress. Ta. In particular, when a semiconductor device employing this resin-sealed package is incorporated into a device, if it is fixed by screwing or the like from above the case 1, the vertical wall portion of the case 1 will have a part that spreads outward (i.e., the case There was a risk that the resins 6 and 7 would be peeled off from the case 1 due to the stress that would cause them to separate from the resins 6 and 7 in the case 1.

The present invention was developed in view of the above-mentioned conventional problems, and its purpose is to provide a resin-sealed package in which resin is injected into the case, hardened, and molded. The purpose is to improve the joint strength against the stress that tends to expand the side wall of the case outward at the joint surface of the case.

<Means for Solving the Problems> In order to achieve the above object, the resin-sealed package according to the present invention has a screw fixing part for an external device on the outside of the lower part of the case, and a part to be sealed in the bottom opening inside the case. and a resin is filled in the case so as to cover the object to be sealed, wherein a hook portion is provided on a side wall of the case and protrudes inwardly from an upper opening and bends downward. are integrally provided, and the hook portion is embedded in the sealing resin.

<Function> The present invention has the above-mentioned configuration, that is, it has a screw fixing part for an external device on the outside of the lower part of the case, a body to be sealed is placed in the bottom opening inside the case, and a resin is applied so as to cover the body to be sealed. In the resin-sealed package formed by filling the case into the case, a hook part that protrudes inward from the upper opening and bends downward is integrally formed on the side wall of the case. When the case is fixed, even if stress is applied to the vertical wall of the case to try to spread it outward, the final sealing resin will sink into the hooks provided on the side wall of the case and be pulled inward, causing the case and the inside of the case to Interfacial peeling of the injected resin at the joint surface is less likely to occur, and it can withstand up to the strength of the case material.

That is, the hook portion provided on the side wall of the case has a shape that engages with the resin injected and solidified inside the case, so that peeling and distortion of the resin injected into the case from the case is suppressed, and joint strength can be improved.

<Example> Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view of a resin-sealed package that is an example of the power transistor module of the present invention.

Note that the same functional parts as in FIG. 2 are indicated by the same numbers.

In FIG. 1, a rectangular cylindrical resin case 1 with an upper opening is integrally provided with a plurality of hook parts 10 on a side wall thereof, which protrude inwardly from the upper opening and bend downward. Therefore, when the internal casting resin 6 is injected and solidified into the inside of the case 1, and the final sealing resin 7 is further injected and solidified so as to cover the internal casting resin 6 to form a package, the internal casting resin 6 is injected into the case 1. The internal casting resin 6 and the final sealing resin 7 have a shape that engages with the hook portion 10 of the case 1, and it is possible to suppress peeling of the resins 6 and 7 inside the case 1 due to external stress or the like.

In the same figure, reference numeral 1a denotes a through hole provided in a screw fixing portion for an external device outside the lower part of the case 1, and this portion is fixed with a screw when the device is assembled into the device. Reference numeral 10a designates a hole provided in the hook portion 10 to allow air trapped in the hook portion to escape when resins 6 and 7 are injected into the case 1.

Furthermore, in the above embodiment, the resin filled inside the case 1 is configured as two layers consisting of the internal casting resin 6 and the final sealing resin 7, but the present invention is not limited to this.

<Effects of the invention> As described above, according to the invention, the hook portion provided near the upper opening on the inner surface of the side wall of the case,
Since it has a shape that engages with the resin injected and solidified inside the case, by adding a simple configuration, it is possible to easily suppress the peeling and distortion of the resin injected into the case from the case, and improve the joint strength.

[Brief explanation of drawings]

FIG. 1: A cross-sectional view of a resin-sealed package that is an example of the power transistor module of the present invention. Figure 2: One of the conventional power transistor modules
FIG. 2 is a cross-sectional view of an example resin-sealed package. 1... Case, 2... Heat dissipation board, 3... Internal circuit board, 4... Internal circuit components, 6... Internal casting resin, 7... Final sealing resin, 10... Hook.

Claims (1)

[Scope of utility model registration request] There is a screw fixing part for external equipment on the outside of the bottom of the case, and the object to be sealed is placed in the bottom opening inside the case.
In the resin-sealed package in which the case is filled with resin so as to cover the object to be sealed, a hook portion that protrudes inward from the upper opening and bends downward is integrally formed on the side wall of the case. A resin-sealed package characterized in that the hook portion is embedded in the sealing resin.