JPH0246675A - Manufacture of connector - Google Patents

Abstract

PURPOSE:To improve close adhesion of an insulator and contacts so as to prevent a flux rise by pressing contacts into contact-holding holes followed by impressing ultrasonic oscillation on the contacts for making to slide them to the internal walls of the contact-holding holes. CONSTITUTION:After pressing contacts 31 into contact-holding holes 21, ultrasonic oscillation is impressed on the contacts 31 for making them to slide to the internal walls of the contact-holding holes 21. The internal walls are compression-elastically deformed by pressing-in of the contacts 31. When in this state ultrasonic oscillation is impressed on the contact 31 with prescribed energy, the internal walls of the press-in parts are softened due to friction heat or the like to generate a plastic flow of a resin material in the direction to relieve internal stress for stopping gaps to stick to the external peripheries of the contact-holding parts 21. Thereby, a flux rise from the terminal side to the side of the contact points can be prevented.

Description

[Detailed Description of the Invention] [Summary] This invention relates to a method of manufacturing a connector, in particular a method of manufacturing a connector that does not cause flux build-up when soldering and mounting it on a printed circuit board, etc., and when assembling and inserting a contact into an insulator. The purpose of the present invention is to provide a method for manufacturing a connector that improves the adhesion between an insulator and a contact, eliminates gaps, and prevents flux build-up. In a contact assembly step of fitting and fixing a press-fitting part of a contact having a contact part at one end, a press-fitting part in the middle, and a terminal part at the other end into the contact holding hole, the contact is inserted into the contact holding hole. After the contact is press-fitted, ultrasonic vibration is applied to the contact to cause it to slide against the inner wall of the contact holding hole.

[Industrial application field]

The present invention relates to a method for manufacturing a connector, and particularly to a method for manufacturing a connector that does not cause flux build-up when soldering and mounting the connector on a printed circuit board or the like.

When using dip soldering for connectors mounted on printed circuit boards, solder flux sometimes enters the contact side of the contact through the gap between the contact holes in the insulator, contaminating the contact and causing contact failure.

Various structures have been studied to prevent such flux from rising.

[Conventional technology]

FIG. 3 is an exploded view of the connector mounted on the printed board.

A connector that is soldered and mounted on a printed circuit board usually has a contact part 11, a press-fit part 12, and a terminal part 1 in a contact holding hole 21 of an insulator 2 made of a molded thermoplastic resin.
A plurality of contacts 1 having 3 are fitted and fixedly held at the press-fitting portions 12.

The press-fitting part 12 of this contact is formed to have a slightly smaller cross-sectional shape than the contact holding hole 21 having a square cross-section, and has a protrusion 12a in the plate thickness direction and a bulge part 12 on the side surface (press-cut surface).
b is partially formed and has a slightly larger outer diameter than the contact holding hole 21. When the press-fit portion is inserted into the holding hole, the large diameter portion elastically deforms the inner wall of the holding hole 21 and bites into the contact holding hole 21. The contact date is held on the insulator 2 by the adhesive force.

When mounting such a connector on a printed board, insert the terminal part of the contact protruding from one side of the insulator into the through hole of the printed board and place it there. It is attached and connected.

During this soldering process, if there is a minute gap between the contact and the contact holding hole in the insulator, "flux wicking" occurs in which solder flux oozes out to the contact side of the contact due to capillary action. This flux buildup contaminates the contact portions that require cleanliness and significantly deteriorates the contact performance, so various methods have been taken to prevent this.

A structure in which the insulator is lifted off the printed circuit board by a protrusion (standoff) provided on the lower surface of the insulator and the contact holding hole is separated from the soldering position is often used, but this is not sufficient.

The most effective way to completely prevent flux from rising is to eliminate the gap between the contact and the insulator. For this purpose, an insert molding method is used in which a through hole is not provided in the insulator and contacts are inserted and integrally formed when the insulator is molded.

[Problem to be solved by the invention]

Insert molding requires a plurality of contacts to be arranged in a high-temperature mold, which results in a longer molding time and a more complicated mold and molding machine, resulting in increased costs.

Furthermore, in a structure in which the contact part is housed in a contact hole of an insulator, such as a female contact having a spring part, insert molding is extremely difficult, so there is a problem that it cannot be applied to all types of connectors.

The present invention was created in view of the above-mentioned problems, and provides a method for assembling a connector that has good adhesion between the insulator and the contacts, eliminates gaps, and prevents flux build-up when inserting and assembling contacts into the insulator. The purpose is to

[Means to solve the problem]

The above-mentioned problem is solved by inserting the press-fitting part of the contact into the insulator, which is made of a molded article of thermoplastic resin material and has a contact holding hole, and has a contact part at one end, a press-fitting part in the middle, and a terminal part at the other end. In the contact assembly process of fitting and fixing the contact into the holding hole, after press-fitting the contact into the contact holding hole,
The problem is solved by the method of manufacturing a connector of the present invention, which comprises applying ultrasonic vibration to the contacts to cause them to slide against the inner wall of the contact holding hole.

[Effect]

The inner wall is compressively and elastically deformed by press-fitting the contact.

When ultrasonic vibration is applied to the contact with a predetermined energy in this state, the inner wall of the press-fit part softens due to frictional heat, etc., and plastic flow of the resin material occurs in the direction of relieving internal stress, closing the gap and forming the contact holding part. Closely adheres to the outer periphery of the

This can prevent flux from rising from the terminal side to the contact side.

〔Example〕

The present invention will be explained in detail below with reference to the accompanying drawings.

FIG. 1 is an explanatory diagram showing the connector manufacturing method of the present invention.

2 is a substantially rectangular insulator made by molding thermoplastic resin, and has a rectangular contact holding hole 21 that penetrates the upper and lower surfaces.
A plurality of pieces are formed with a predetermined pinch.

3 is a strip-shaped contact member in which a plurality of contacts 31 are connected by a connecting portion 32 with the same pinch as the contact holding hole. Each contact 31 has a male contact portion 32 that contacts, for example, a mating female contact at one end, a press-fit portion 34 that is inserted into the contact holding hole 21 in the middle, and a press-fit portion 34 that is inserted into a through hole of a printed board at the other end. A terminal portion 35 to be connected by solder is formed.

Bulge portions 34a are formed on both sides of the press-fitting portion 34, and projections 34b are partially formed in the thickness direction of the press-fitting portion 34, and the maximum external shape thereof is slightly larger than the contact holding hole 21.

4 is a horn that generates ultrasonic vibrations, and is also used as a contact insertion jig. For this purpose, a groove 41 is formed on the lower surface of the horn 4 to engage the plate thickness of the connecting portion 32 of the contact member, and is held movably downward by a press mechanism (not shown) to push the contact member downward. Press or apply pressure to the contact member with an amplitude of 10 μm in the vertical direction.
It is now possible to apply ultrasonic vibrations up to about m.

To insert the contact, first lower the horn and press the contact member 3 downward with a predetermined pressing force.

? The contacts 31 of jJIi are press-fitted into the contact holding hole 21 all at once. Then, as shown in the cross-sectional view (a) of FIG. 2, the press-fitting part 34 of the contact comes into contact with the inner wall of the contact holding hole 21 with its bulge part and protrusion 34b, is elastically deformed, bites in, and is fixedly held. . (The figure shows the protrusion 34b, but since this protrusion is formed in a part of the width of the contact, there is a gap passing through the top and bottom on both sides of the protrusion.) In this state, the inner wall of the insulator A compressive stress as shown by arrow B is generated.

Next, with the contact still pressurized with horn 3,
The horn 3 is vibrated for a predetermined period of time using an appropriate high frequency power of several tens of KHz. Then, this ultrasonic vibration is transmitted to each contact, causing the contact to vibrate as shown by arrow A, causing the bulge portion 34a and protrusion 34b of the press-fit portion to be connected to the contact holding hole 21.
sliding occurs on the inner wall, the resin material is heated by frictional heat, the inner wall melts, plastic flow of the resin material occurs in the direction of relieving compressive stress, and the resin material flows into gaps other than the protrusion 34b and the bulge. 2(b), and comes into close contact with the surface of the press-fit portion 340 of the contact.

Thereafter, the connecting portion 32 is cut to a predetermined length, and the assembly of the connector is completed.

In this way, by applying ultrasonic vibration after press-fitting the contacts, the gap in the contact holding hole is eliminated, so when dip soldering is performed to mount the connector on a printed circuit board, it is possible to apply ultrasonic vibration from the terminal side to the contact side. It is possible to eliminate solder flux build-up. In addition, this manufacturing method simply adds ultrasonic vibration to the conventional manufacturing method of separately manufacturing and assembling contacts and insulators, and provides excellent flux build-up prevention similar to that achieved using complex insert molding methods. It is possible to obtain the effect.

〔Effect of the invention〕

As explained above, according to the present invention, by applying ultrasonic vibration to the contacts after press-fitting, it is possible to inexpensively manufacture a connector with excellent flux build-up prevention effect by closing the gap in the contact holding hole. .

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the connector manufacturing method of the present invention, FIG. 2 is a sectional view showing the close contact of contact holding holes, and FIG. 3 is an exploded perspective view of the connector for mounting on a printed board. In the figure, 2--Insulator, 21- Contact holding hole,
3...-contact member, 3t-contact, 32-
・Series connection portion, 33-・Contact portion, 34-・Press-fitting portion, 35-・Terminal portion, 34a-=bulge portion, 34b-protrusion. Conc 7L press fit (

Claims (1)

[Claims] An insulator (2) made of a molded article of thermoplastic resin material and having a contact holding hole (21) has a contact portion (33) at one end.
), a press-fit part (34) of a contact (31) having a press-fit part (34) in the middle and a terminal part (35) at the other end is fitted into the contact holding hole (21) and fixed. , the contact (31) is inserted into the contact holding hole (21).
) A method for manufacturing a connector, comprising: applying ultrasonic vibration to the contact (31) after press-fitting the contact (31) into the contact hole (21) to cause the contact to slide against the inner wall of the contact holding hole (21).