JPH0364876A - Lead terminal fitting to electronic parts - Google Patents

Abstract

PURPOSE:To prevent deviation of a holding position in a heating process by fitting projection parts and fitting holes into insertion holding holes of a clip type lead and a circuit board. CONSTITUTION:Projection parts 2d and a fitting hole 1c are arranged, and firstly a circuit board is inserted into a holding part of a forked elastic piece 2a. At this time, due to extension transfer by point contact of the tip of the projection part 2d, insertion operation is performed with the reduced insertion force as compared with the former surface contact transfer, while simultaneously with a completed inserting operation, the projection part 2d is fitted into a fitting hole 1c provided inside a terminal pattern 1b of the circuit board 1 so that positioning is cramped in a prescribed position. The terminal pattern 1b and the forked elastic piece 2a are soldered with a solder 3 by a solder dipping process or the like. Thereby, in the heating process of soldering, an interholder distance of the clipping part is widened by thermal expansion so that generation of nonconformity such as positional deviation or coming-off of a lead can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for attaching lead terminals of electronic components, particularly using clip-type leads as external connection leads.

[Conventional technology]

Fig. 3 is a diagram showing how the lead terminal of a conventional electronic component is attached, and Fig. 3(a) is a partially enlarged front view;
FIG. 3(b) is a side view of FIG. 3(a). In the figure,
Reference numeral 1 designates a circuit board 1. On the circuit board 1, there are formed wiring lines 1a connected to semiconductor elements (not shown), etc., and terminal patterns lb to which leads to be described later are soldered. Further, a plurality of terminal patterns 1b are arranged in parallel at regular intervals on the side of the circuit board l. 2 is a clip type lead,
As shown in the figure, the clip-type lead 2 has a bifurcated elastic piece 2a formed at one end that clamps the sides of the circuit board 1 from both the front and back sides, and is attached to a motherboard (not shown) or a daughter board (not shown). An external connection piece 2b to be connected is integrally formed on the other end, and the terminal pattern 1b of the circuit board]
A plurality of bifurcated elastic pieces 2a are attached to one circuit board l by soldering. Note that 3 is solder.

Next, a procedure for assembling a lead terminal of a single in-line semiconductor device using the clip-type lead 2 configured as described above will be described. First, the bifurcated elastic piece 2a
A circuit board 1 is inserted into the clamping part of the circuit board 1, and the circuit board 1 is crushed with a clip type lead 2. Then, as shown in the figure, the terminal pattern 1b and the bifurcated elastic piece 2a are soldered using a solder dip or the like in a soldering process. In this state, the clip lead 2 is electrically connected to the circuit board 1 and firmly fixed. Next, hold a plurality of clip-type leads 2 in parallel at equal intervals, and attach the tie bar part 2C side held in the form of a lead frame to the tie bar lead with a predetermined lead length (line A).・It will be sorted. In addition, the two-dot chain line in FIG. 2 indicates the position of the tie bar lead counter.

[Problem to be solved by the invention]

Conventional single in-line semiconductor devices were constructed as described above, but due to variations in the thickness of the circuit board (e.g. printed wiring board: 66 x 0.19), a stable clamping condition could not be obtained and only one circuit There are problems in that the board is likely to fall off or be insufficiently inserted, and there are also problems in that the clamping position shifts due to thermal expansion of the clip-type leads during the heating process for soldering.

This invention was made to solve the above-mentioned problems, and it is possible to obtain a stable clamping state regardless of variations in the thickness of the circuit board.

The object of the present invention is to provide a method for attaching a lead terminal of an electronic component in which the clamping position does not shift during a heating process.

[Means to solve the problem]

In the method for attaching lead terminals of electronic components according to the present invention, protrusions of the contact portions of bifurcated elastic pieces that clamp the sides of the circuit board from both the front and back sides are protruded, and protrusions are provided in the soldering pads of the circuit board. A mounting hole is provided into which the part fits.

[Effect]

In this invention, the protrusions of the bifurcated elastic pieces are fitted and clamped into the mounting holes in the circuit board terminal pattern, thereby reducing the insertion force due to the contact movement at the time of insertion, and regardless of the variation in the thickness of the circuit board. The circuit board will not fall off,
Prevents the clip lead from shifting.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure shows the connection state of the leads of a single in-line type semiconductor device which is an embodiment of the present invention.
is a front view showing an enlarged view of the main parts, and Fig. 1(b) is a front view showing the main parts enlarged.
FIG. 2 is an enlarged sectional view taken along line 1-1 in FIG. 1(a). In the figure, 1 is a circuit board, 2
The clip lead 2 is a clip lead 2 that holds the sides of the circuit board from the front and back sides and connects the bifurcated elastic piece 2a and the motherboard (not shown) to be soldered to the solder terminal pattern 1b of the circuit board 1. ), etc. External connection piece 2b
It is composed of. ]6 is a mounting hole 2d provided in the center of the solder terminal pattern 1b of the circuit board 1;
is a protruding protrusion machined at the contact portion of the bifurcated elastic piece 2& of the clip-type lead 2 which is fitted into the attachment hole 10.

The clip type lead 2 and the circuit board l configured in this way
The method for assembling a single in-line type semiconductor device using this method is the same as the conventional method. However, a protrusion 2d and a mounting hole IC are provided. First.

The circuit board l is inserted into the holding portion of the two-stage elastic piece 2a.

At this time, since the protrusion 2d extends by making point contact with the tip of the protrusion 2d, the insertion operation is performed with a reduced insertion force compared to the conventional surface contact extension movement, and as soon as the insertion operation is completed, the protrusion Since the portion 2d is fitted into the mounting hole 10 provided in the terminal pattern 1b of the circuit board 1, it is positioned and clamped at a predetermined position.

Then, the terminal pattern [b] and the bifurcated elastic piece 2a are soldered using solder 3 in a solder dip process or the like.

Although the above embodiment describes a single in-line semiconductor device, the present invention is not limited to this embodiment. Needless to say, the present invention can also be applied to composite parts having clip-type external lead terminals such as dual in-line type, zigzag in-line type, and surface mount type.

〔Effect of the invention〕

As described above, according to the present invention, the protrusion 2d and the mounting hole Iaf are fitted into the insertion and clamping hole of the clip type lead and the circuit board, so that a stable clamping state can be maintained regardless of variations in the thickness of the circuit board. Therefore, if the circuit board varies toward the thinner side, it is possible to prevent the board from falling off, and if the circuit board varies toward the thicker side, problems such as insufficient insertion amount can be prevented. In addition, even if the clamping force is low at room temperature, the distance between the clamping parts of the soldering part expands due to thermal expansion during the heating process of soldering, causing the leads to shift in position or fall off. At the same time, problems such as the occurrence of such problems can be prevented.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a single in-line type semiconductor device which is an embodiment of the present invention. FIG. 1(a) is a front view showing the main parts, and FIG. 2 is an enlarged sectional view taken along the line T of FIG. 1 (al), and FIG.
Figure (a) is a front view showing a part, Figure 3 (b) is Figure 3 (
&) is a side view. 1... Circuit board, 2... Clip type lead, lo
...Protrusion, 2d...Mounting hole. In addition, it is shown. The same reference numerals in the figures refer to the same or corresponding parts. 4) N C 2C Figure 8 - (b)

Claims (1)

[Claims] A bifurcated elastic piece that holds the sides of an electronic component board from both the front and back sides and is soldered to the soldering pad of the board, and a bifurcated elastic piece that extends to one elastic side of the bifurcated elastic piece. 1. A method for attaching a lead terminal of an electronic component, comprising: an external connection piece that is formed integrally with the substrate, is disposed closer to the main surface than the center in the thickness direction of the substrate, and is connected to an electronic component mounting section.