JPH059958B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a structure for fixing a coated thick film integrated circuit board and a case.

In recent years, there has been a trend toward miniaturization of electronic components mounted on electronic devices and high-density mounting on circuit boards. Such a thick film integrated circuit board is then housed and mounted in a case in consideration of environmental conditions.

[Prior Art] Fig. 3 shows a conventional fixing structure between a thick film integrated circuit board (also simply referred to as a circuit board) and a case.
A is a front sectional view, and b is a side sectional view.

A thick film integrated circuit is formed on a circuit board 1 made of ceramic, a circuit component 2 is mounted thereon, a single element array 3 is attached to one side, and a protective film made of silicone protective resin or the like is formed on a part or the whole. The case body 4 is filled with an adhesive filler 6, and the case body 4 is sealed and fixed with a case lid 5.

FIG. 4 is a perspective view showing a conventional fixing structure between a thick film integrated circuit board and a case, which is different from that shown in FIG. 3, but the same parts as those in FIG.

In FIG. 4, a thick film integrated circuit is formed on a ceramic circuit board 1, a circuit component 2 is mounted thereon, a terminal row 3 is attached and connected to one side, and a protective film 8 is partially or entirely covered. , and insert it into the box-shaped case main body 7 in the direction of the arrow by fitting it along the guide groove. One protruding end 71 forming the guide groove protrudes beyond both ends of the terminal row 3 of the inserted board 1, and the position is determined. The case body 7 is a thermoplastic resin molded product, and the protruding ends 71 are heated and softened, and then bent and deformed onto the end surface of the substrate 1, and fixed by so-called heat caulking.

[Problems to be Solved by the Invention] The above-mentioned conventional fixing structure according to the method shown in FIG. It required In addition, with the method shown in Figure 4, it is difficult to control the temperature for softening and deforming, the shape is not constant because it is done manually, the fixing strength varies, and there are problems with the reliability of fixing. It was hot.

[Means for solving problems]

The present invention provides a fixing structure that solves the above-mentioned conventional problems, and includes a row of fork-shaped lead terminals on one side of a rectangular ceramic circuit board, which clamps and connects the circuit board with the fork-shaped part. A resin coating is applied to the circuit board including the prongs, and the circuit board is inserted into a box-shaped case body, and the tip of the circuit board is positioned by contacting the bottom of the case, and the circuit board protrudes into the case opening of the case body. By covering the case opening with a case lid having an insertion hole through which the terminal lead is inserted, a protrusion on the inner surface of the case lid provided adjacent to the insertion hole can cover the pronged portion of the lead terminal with resin. The circuit board is fixedly supported within the case by pressing the circuit board through the case.

[Effect]

The fixing structure between the thick film integrated circuit board and the case is as follows:
A circuit board is inserted and positioned in the box-shaped case body, and a case lid covering the opening of the case body supports the lead terminals by inserting them into the insertion holes. When the protrusions on the inner surface of the case lid press the lead terminals, the circuit board is pressed in the width direction, and the circuit board is pressed and fixed in the direction in which it has the highest strength. As described above, the structure obtained through a series of sealing steps can be fixed, and no special fixing work is required.

〔Example〕

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram illustrating an embodiment of a fixing structure for a thick film integrated circuit board and a case according to the present invention, and is a perspective view in a separated state, and FIG. 2 is a side sectional view in an assembled state. Note that parts equivalent to those in FIGS. 3 and 4 are designated by the same reference numerals.

A thick film integrated circuit (not shown) is formed on a circuit board 1 made of rectangular ceramic, and circuit components 2 are mounted thereon, and a terminal row 3 consisting of a plurality of fork-shaped terminals is sandwiched between the fork-shaped parts on one side. and connect it to a circuit pattern (not shown).

Next, the entire surface of the circuit board, including the prongs 31, except for the linear lead portions of the terminals 3, is coated with a protective film 8 made of a silicone resin or the like having a safety-protecting quality. This circuit board 1
Insert the box-shaped case body 4 made of, for example, a synthetic resin molded product as shown by the arrow. Although the case body 4 is not shown, guide grooves are integrally molded on both sides of the inner surface to sandwich and guide the thickness of both ends of the circuit board 1.
This prevents the substrate 1 from tilting. Alternatively, the thickness of the protective film 8 can be increased as appropriate, and as shown in the figure, it can be brought into contact with the inner surface of the case body 4 to prevent tilting.

In any case, the tip of the inserted substrate 1 comes into contact with the bottom surface of the case body 4 via the protective film 8, and the insertion position is determined. In this state, only the linear lead portions of the terminals 3 protrude from the opening of the case body 4.

The case lid body 9 made of a synthetic resin molded product that covers the opening of the case body 4 has an insertion hole 92 through which the lead portions of a plurality of terminals 3 can be inserted, and an insertion hole 9 on the inner surface side.
A protrusion 91 is integrally formed in contact with 2.

The leads of the terminals 3 of the circuit board 1 inserted into the case body 4 are inserted so that the insertion holes 92 of the case cover 9 are aligned, and the case cover 9 is fitted into the opening of the case body 4. A recess is formed on the inner surface of the case body 4, and a protrusion (not shown) formed around the case lid 9 engages with this recess, and the case lid 9 is locked to the case body 4. be done.

Describing the state in which the circuit board 1 is fixed to the cases 4 and 9 in the above process, the tip of the protrusion 91 adjacent to the insertion hole 92 of the case lid 9 is connected to the terminal 3.
The fork-shaped portion 31 is pressed from the outside, and since the silicone resin 8 of the protective quality is sandwiched in this portion as described above, the pressure is applied via this silicone resin 8. On the other hand, the silicone resin 8 is also sandwiched in the same way at the tip end of the circuit board 1 which is in contact with the bottom surface of the case body 4, so this contact relationship is also performed via the silicone resin 8. In this way, the tip of the circuit board 1 is pressed by the prongs 31 of the terminal 3, but the mutual dimensions are adjusted so that the tip is fixed and supported by the elastic compression of both the protective silicone resins 8. The relationship is determined.

Since the circuit board 1 is compressed in the width direction, this is the direction in which the ceramic is most strongly compressed, and stable fixation can be achieved. Since the terminal 3 is also pressed and fixed, the terminal 3 will not be affected by any external force applied to the terminal 3.
This will provide stable support.

〔Effect of the invention〕

As explained above, according to the present invention, it is easy to house the thick film integrated circuit board in the case and securely support it, and it is also reliable and stable, so it has practical effects such as improved fixation reliability. is extremely significant.

[Brief explanation of the drawing]

1 is a perspective view of an embodiment of the fixing structure for a thick film integrated circuit board and a case according to the present invention in a separated state, FIG. 2 is a side sectional view in an assembled state, and FIG. The figures show a conventional fixing structure; a is a front sectional view, b is a side sectional view, and FIG. 4 is a perspective view of a conventional fixing structure different from FIG. 3. In the figure, 1 is a thick film integrated circuit board, 2 is a circuit component,
3 is a terminal, 4 is a case body, 5 and 9 are case lids, 6 is a filling material, 8 is a protective film, 31 is a pronged portion, 9
1 indicates a protrusion, and 92 indicates an insertion hole.

Claims (1)

[Scope of Claims] 1. A fork-shaped lead terminal array is formed on one side of a rectangular ceramic circuit board, and the circuit board is sandwiched and connected by the fork-like portions, and the circuit board including the fork-like portions is coated with a resin. The circuit board is inserted into a box-shaped case body, and the tip of the circuit board is positioned in contact with the bottom of the case, and the case lid body has an insertion hole through which the lead of the terminal protrudes into the case opening of the case body. By covering the case opening, the protrusion on the inner surface of the case lid provided adjacent to the insertion hole presses the prongs of the lead terminal through the resin coating, thereby fixing and supporting the circuit board within the case. A fixing structure between a thick film integrated circuit board and a case.