JPH01204316A - Hermetic seal structure of electric part - Google Patents

Abstract

PURPOSE:To make the sealing of a wafer open face perfect by covering the open face of a casing with a fixed contact piece buried under the casing, covering a hole provided in the fixed contact piece with a pasted isolation sheet, and burying both the fixed contact piece and the isolation sheet in the wafer. CONSTITUTION:A box-shaped portion is provided, in a movable contact piece 6 and an elastic arm 12 provided with an operation part 10 and a contact part 11 is cut and raised up from the bottom face of the box-shaped portion. A plate-shaped body to fill a hole provided on the bottom face of the box-shaped portion, is stuck to the bottom face. On the other hand, a horizontal portion 2 for covering the open face of the movable contact piece 6 is provided in a fixed contact piece 1, and a hole 4 for allowing projection of the operation part 10 of the elastic arm 12 is provided in the horizontal part 2, and an isolation sheet 5 having elasticity is stuck to the upper face of the horizontal part 2. The horizontal part of the movable contact piece 6 is stuck to a flange part 15 which is provided outside the open face of the box-shaped portion of the movable contact piece 6 through the isolation sheet 5. Under the condition that the operation part 10 of the elastic arm 12 is projected from the hole 4 of the horizontal part together with the isolation sheet 5, the movable contact piece 6, the contact piece 1 and the isolation sheet 5 are inserted in a wafer and formed. Thus, a high hermetic seal structure against an outside liquid can be obtained.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a sealed structure for electrical components such as switches, and in particular, the present invention is characterized in that the switch can be cleaned together with the board to remove flux. be.

[Conventional technology]

For example, when mounting a dual in-line switch (hereinafter referred to as a DIP switch) on a board, after soldering the terminals normally provided on the DIP switch to the board, the soldering process sometimes involves removing the flux used. In order to perform such cleaning on the entire board, it is necessary that the DIP switch has a sealed structure, and the one shown in FIG. 7 is conventionally known as a sealed structure.

In FIG. 7, reference numeral 21 denotes a box-shaped case molded from synthetic resin, and a plurality of pairs of terminals n made of conductive material are arranged at predetermined intervals on both sides of the case 210. , these terminals B form the contacts of the switch inside the case 21. A panel made of synthetic resin or metal is integrally stacked on top of the case 21, and the panel and the case 21 form the outer shell of the switch, that is, the casing. The casings 21, 24
There is a slide and a movable contact 23 in the cavity A inside the
A plurality of sliders 23b are movably housed, and knobs 23a protruding from the upper part of these sliders are exposed in each of a plurality of holes 24a drilled in the panel.

Therefore, a desired circuit can be obtained by operating the knob 23a from above the panel and selecting the contact state between the movable contact 23b and the terminal portion. DI configured like this
A film-like tape 5 made of synthetic resin, metal foil, etc. is attached to the upper surface of the casing of the P switch, that is, the upper surface of the panel so as to close the hole 24a, and the cavity A is sealed by the tape 5. has been done.

When mounting such a DIP switch with a sealed structure on a board (not shown), each terminal 22 is inserted into a hole in the board.
Lux is applied and each terminal part and the pattern of the board are fixed by soldering. If the flux is left as it is after soldering, the pattern is likely to corrode, so once the soldering is completed, the flux is removed by washing with water or the like. At this time, since the DIP switch has a sealed structure with the tape 5 attached to the top surface of the casing,
The cleaning liquid does not get into the cavity A during cleaning, so the soldered DIP switch can be cleaned along with the board. After the DIP switch is mounted on the board in this way, the tape 5 can be removed with your fingers and the knob 23a can be operated as shown in FIG. Knob 23a
A desired circuit is formed by manipulating the .

[Problem to be solved by the invention]

However, in the seal structure as described above, the tape 5
Due to the heat of soldering, the air inside the cavity A of the IP switch expands, and this expanded air blows out from the adhesive surface of the tape 5 and the casing, causing failure. Desired pores are formed. These pores are formed by DIP of the cleaning solution used during cleaning.
Since it becomes a conduction path to the inside of the switch, it may cause contact failure such as short circuit or corrosion of the switch contacts.Especially when cleaning immediately after soldering, there is no pressure between the atmospheric pressure and the air pressure inside cavity A. Because of this difference, the amount of cleaning liquid that enters into the cavity A becomes significant. Therefore, an object of the present invention is to provide a hermetically sealed structure that has a high degree of sealing against external liquids and also allows for primary molding of wafers.

[Elaborate means to solve problems]

In order to achieve the above objects, the present invention provides a movable contact piece with a box-shaped part having an open surface, and an elastic arm provided with an operating part and a contact part is cut out from the bottom of the box-shaped part. By cutting and raising the elastic arms, a plate-like body for closing the hole provided in the bottom surface of the box-shaped part is glued to the bottom surface, and on the other hand, a horizontal plate is attached to the fixed contact piece to cover the open surface of the movable contact piece. The horizontal part is provided with a hole through which the operating part of the elastic arm protrudes, and an elastic insulating sheet is added to the upper surface of the horizontal part, and the outside of the open surface of the box-shaped part of the movable contact piece is provided. The horizontal part of the movable contact piece is glued to the flange provided on the flange via an insulating sheet, and the operation part of the elastic arm is made to protrude together with the insulating sheet from the hole in the horizontal part, and in this state, the movable contact piece and the fixed contact piece are On the other hand, an insulating sheet is insert molded into Ueno.

[For production]

That is, according to the above means, the open surface of the casing is
The hole provided in the fixed contact piece is covered by a fixed contact piece embedded in the casing, and the hole provided in the fixed contact piece is covered with an insulating sheet+table\ which is stuck to the fixed contact piece and closes the hole. Since both the insulation size and t are buried in Ueno,
The seal on the open side of the wafer is complete, so there is no risk of external liquids entering into the cavity of the wafer. Furthermore, the open surface of the box-shaped part of the movable contact piece is sealed with the horizontal part of the fixed contact piece and the insulating sheet, and the bottom surface of the box-shaped part is closed with a root-like body. Since the wafer can be primarily formed by embedding an insulating sheet, the cost is low.

〔Example〕

Embodiments of the present invention will be described below with reference to the accompanying drawings.

1 to 6 show a DI equipped with two contact portions according to the present invention.
FIG. 1 is a perspective view of the fixed contact piece, FIG. 2 is a perspective view of the fixed contact piece with an elastic insulating sheet pasted on it, and FIG. 3 is a movable contact piece. Perspective view of 4th
The figure is a perspective view of the box-shaped part of the movable contact piece with an insulator attached to the top flange and a plate-shaped body attached to the bottom. Figure 6 is DIP
FIG. 3 is a cross-sectional view of the switch.

In Fig. 1, reference numeral 1 denotes a pair of fixed contact pieces, each fixed contact piece 1 consists of a horizontal part 2 and a terminal part 3, and each horizontal part 2 has an operating part provided on the elastic arm of a movable contact piece, which will be described later. It has a hole 4 from which it protrudes. Reference numeral 5 denotes an elastic insulating sheet that covers the upper surface of the horizontal portion 2 of the double-sided constant contact piece 1. Reference numeral 6 designates a pair of movable contact pieces, each of which is branched at the center and consists of a box-shaped part 8 having an open surface 7 and a terminal part 9. Operation part 10 and chevron contact part 1
By cutting and raising both elastic arms 12, a plate-like body 14 for closing two holes 13 formed in the bottom surface of the box-shaped portion 8 is pasted. A double-sided adhesive insulating tape 16 is adhered to the flange 15 on the upper surface of the box-shaped portion 8.

The horizontal part 2 of the fixed contact piece 1 as described above is adhered to the flange part 15 of the box-shaped part 8 of the movable contact piece 6 via a double-sided adhesive insulating tape 16. As shown in FIG. 5, the fixed contact piece 1. Resin is poured into the space 19 formed surrounding the movable contact piece 6, and insert molding of the wafer is performed. Thereafter, the terminal portion 3.9 is separated and then bent downward.

As a result, a pair of fixed contact pieces 1, a pair of movable contact pieces 6,
The insulating sheet 5 is embedded in the wafer pad, and in FIG. At this time, each movable contact piece 6
The contact portion 11 comes into elastic contact with the lower surface of the horizontal portion 2 of each fixed contact piece 1, and the contact of the DIP switch is turned on.

For example, in the DIP switch as described above, one movable contact piece 6
By pressing the operating part 10 from above the insulating sheet 5 with a lever (not shown), the contact part 11 is separated from the horizontal part 2 of the fixed contact piece 1, the contact becomes OFF, and the pressing force of the lever is removed. For example, the restoring force of the elastic arm 12 returns to the original state shown in FIG. 6, and the contact of the DIP switch is turned ON.
becomes. A similar effect occurs when the operating portion 10 of the other movable contact piece 6 is pressed.

When mounting the DIP switch configured as described above on a board (not shown), apply 7 lux with each terminal part 3, 9 inserted into the hole in the board, and connect each terminal part 3, 9 to the board. Solder to the pattern.

When soldering is completed, the flux is subsequently removed by washing with water or the like.

By the way, the L) IP switch of the present invention has a wafer 20
The open surface of is covered by the horizontal part 2 of the fixed contact piece 1 embedded in the wafer, and the hole 4 of the horizontal part 2 is
The operation part 10 of the movable contact piece 6 is covered with an insulating sheet 5 stuck to the wafer. The sealing of the wafer is completely sealed, so there is no possibility that the cleaning liquid will infiltrate into the cavity C of the wafer from the open surface, and the soldered DIP switch can be cleaned together with the board.

In addition, since wafer molding allows primary insert molding, the cost of the DIP switch can be reduced.

〔Effect of the invention〕

According to the present invention, as described above, the DIP switch is completely sealed and the wafer can be subjected to primary insert molding.

[Brief explanation of the drawing]

Figures 1 to 6 show a DIP with two contact parts according to the present invention.
Figure 1 is a perspective view of the fixed contact piece, Figure 2 is a perspective view of the fixed contact piece with an elastic insulating sheet pasted on it, and Figure 3 is a perspective view of the movable contact piece. Fig. 4 is a perspective view of the movable contact piece with an insulator attached to the upper flange and a plate-like member attached to the bottom of the box-shaped part, and Fig. 5 is a perspective view of the mold structure for insert molding wafers. Cross-sectional view, FIG. 6 is a cross-sectional view of a DIP switch. FIG. 7 is a sectional view showing the sealing structure of a conventional DIP switch, and FIG. 8 is a perspective view showing the operation of peeling off the tape stuck to the DIP switch. 1...Fixed contact piece, 2...Horizontal part, 4...
...hole, 5 ...insulation sheet, 6 ...
...Movable contact piece, 7...Open surface. 8... Box-shaped part, 10... Operation section, 1
1...Contact part. 12...Elastic arm, 13...hole, 14.
...Plate body, 15...Brim part j16...
...Insulating tape j20...Wafer.

Claims (1)

[Claims] The movable contact piece is provided with a box-shaped part having an open surface, and an elastic arm provided with an operation part and a contact part is cut and raised from the bottom of the box-shaped part, and by cutting and raising the elastic arm, the box-shaped part A plate-shaped body for closing a hole provided in the bottom surface of the movable contact piece is glued to the bottom surface, and the fixed contact piece is provided with a horizontal part that covers the open surface of the movable contact piece, and the horizontal part has the elastic arm. In addition to providing a hole for the operation part to protrude, an elastic insulating sheet is glued to the upper surface of the horizontal part, and a flange provided on the outside of the open surface of the box-shaped part of the movable contact piece is movable via an insulating tape. The horizontal part of the contact piece is glued to make the operating part of the elastic arm protrude together with the insulating sheet from the hole in the horizontal part, and in this state, the movable contact piece, the fixed contact piece, and the insulating sheet are insert-molded on the wafer. A sealed structure for electrical parts featuring: