JPS6151801A - Method of producing circuit element with rotary mechanism part - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method of manufacturing a circuit element with a rotating mechanism component, in which a rotating mechanism component is attached to a circuit board.

(Prior art) In general, in hybrid integrated circuits in which chip-shaped circuit elements are mounted on a circuit board made of materials such as ceramics to configure a predetermined electronic circuit, the entire circuit board is closed in order to protect the circuit elements. The wave layer is formed by an insulating tJf resin layer formed by a dipping method or a molding method.

By the way, depending on the electronic circuit formed on the circuit board, as shown in FIG. However, as shown in Figure 4 (,),
A driver 3 adjusts a variable resistor 2 attached to a circuit board 1
After adjustment, this circuit board 1 is immersed in an insulating resin,
As shown in FIG. 4(b), when the insulating resin layer 4 attached to the circuit board 1 is cured to form the exterior of the hybrid integrated circuit,
When the insulation layer 4 is cured, the wiper setting of the variable resistor 2 is +47. The position may be misaligned, or the insulating resin may enter between the sliding portion of the wiper of the variable resistor 2 and the resistor, resulting in unstable contact between the two. For this reason, rotating mechanical components such as variable resistors cannot be used in hybrid integrated circuits.

(Object of the Invention) The present invention has been made in view of the above-mentioned problems in hybrid integrated circuits, etc., and it is possible to cover the circuit board with an insulating +34 resin layer by forming a cavity around the rotating mechanism parts. It is an object of the present invention to provide a method for manufacturing a circuit element with a rotating mechanism component.

(Structure of the Invention) Therefore, in the present invention, a rotating mechanism component attached to a circuit board is covered in advance with a cavity-forming material made of a material that easily melts when heated, and the circuit board is covered with a porous material. The rotary mechanism component is coated with an insulating resin layer, and a cavity-forming material melted by heating is absorbed into the insulating resin layer to form a cavity around the rotating mechanism component.

That is, the present invention forms a cavity around a rotating mechanism component attached to a circuit board by absorbing a cavity-forming material that melts upon heating into a porous insulating resin covering a circuit board, According to the present invention, it is possible to obtain a hybrid integrated circuit in which the rotating mechanism portion is heavily attached.

The present invention will be described in detail with reference to the following figures.

In FIG. 1(a), similarly to FIG. 3, a variable resistor 12 as a rotating mechanism component is attached to a circuit board F111 made of an insulating material such as ceramic.

The plurality of terminals 13 of the circuit board 11 are connected to a measuring device and a power source (not shown), and the variable resistor 12 is adjusted so that the electronic circuit incorporated in the circuit board 11 has desired characteristics. A cavity-forming material 14, such as wax or paraffin, which is solid or semi-solid at room temperature and easily melts when heated, is adhered onto the variable resistor 12. This cavity forming material 1.t is used at least for the wiper and the resistive film of the variable resistor 12 (none of which are shown).

) is formed so that 1 rG.

Next, the circuit board 11 with the cavity forming material 14 glued onto the variable resistor 12 is immersed in a thermosetting insulating material (3) such as phenol-based or Evogishi-based insulating paint made by dissolving fat with a solvent. Then, as shown in FIG. 1(i), an insulating resin layer 15 is formed on the circuit board 11.

When this insulating resin layer 15 is naturally dried and then heated, the insulating resin layer 15 hardens, and at the same time, the wax-like paraffin of the cavity forming material 14 melts, forming the porous insulating resin layer 1.
5 and around the variable resistor 12 as shown in FIG.
As shown in c), a cavity 16 is formed.

In this way, the variable resistor 12 can be controlled by the cavity forming material 1
4, the insulating resin layer 15 is dried and cured, so that the variable resistor 1
To obtain a hybrid integrated circuit with a variable resistor without the wiper No. 2 moving or thermosetting resin entering between the wiper and zero resistance and reducing the contact state between the two. I can do it.

Next, another embodiment of the present invention is shown in FIG. 2(a).

It is shown in FIG. 2(b) and FIG. 2(c).

In this embodiment, the circuit board 11 is insulated. (After forming the fat layer 15, the variable resistor 12 can be adjusted from the outside. As shown in FIG. 2(a), the cavity forming material 14 is placed on the variable resistor 12, cap 17
Glue. In this state, the circuit board 11 is immersed in the same insulating paint as above to form an insulating resin masonry 5 as shown in FIG. 2 (1). Thereafter, after forming a cavity 14 around the variable resistor 12 by the same process as in FIG. 1(C), the insulating resin layer 15 is formed as shown in FIG. 2(C).
Remove the cap I7 by scraping it 1! An opening 18 is formed at the top of the variable resistor 2:', l2 of the cavity 14, and the variable resistor 12 is adjusted through the entire opening 18.

In the above embodiments, insulation? j7 fat layer 15)!
+ (Although we have explained the example of forming by method,
This insulation (the sesame layer 15 is formed by a molding method,
- Can also be done. Further, the resin layer 15 is not limited to thermosetting resin, and may be made of, for example, room-temperature curing resin.

In this case, the cavity forming material 14 may be melted by heating after the insulating JH resin layer 15 has hardened.

The present invention can also be applied to a hybrid integrated circuit in which rotating mechanism parts such as trimmer capacitors and switches are attached to the circuit board 11.

(Effects of the Invention) As is clear from the detailed description above, the present invention has the following effects:
1L of cavity forming material attached around the rotating mechanism parts
The mechanical parts are absorbed into the insulating resin layer of the circuit board on which they are attached and rotated (by forming a cavity around the hole-groove parts, the set position of the rotating mechanical parts will shift while the insulating resin layer is drying and curing). Or by word of mouth (by word of mouth), it is possible to obtain a hybrid integrated circuit with rotating mechanism components in which the circuit board is covered with an insulating resin layer without causing defects in the electrical characteristics of the hole-groove components.

[Brief explanation of drawings]

FIG. 1(a), FIG. 1(11), and FIG. 1(c) are explanatory diagrams of an embodiment of the method for manufacturing a circuit element with a variable resistor according to the present invention, and FIG. 2(a), FIG. 2 (1) and FIG. 2 (c) are respectively explanatory diagrams of another embodiment of the method for manufacturing a circuit element with a variable resistor according to the present invention, and FIG. The plan view of the circuit board shown in FIG.・Circuit board, 12... variable resistor,
13... Edge-114... Cavity forming material, 15
...Insulating resin layer, 16...Cavity, 17...
・Cap, 18...Open 1].

Claims (1)

[Claims] (1) After coating the rotating mechanism parts attached to a circuit board such as a hybrid integrated circuit with a cavity-forming material made of a material that easily melts when heated, a porous insulating resin layer is placed on the outside of the circuit board using a dipping method. Alternatively, at least adjustment of the rotating mechanism parts can be performed by forming the rotating mechanism parts by a molding method, and heating the entire body during or after the formation of the insulating resin layer to melt the cavity-forming material on the rotating mechanism parts and absorbing it into the above-mentioned insulating resin layer. 1. A method for manufacturing a circuit element with a rotating mechanism component, characterized in that a cavity is formed around the part.