JPH0211982B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a heat caulking method in which a mounting member is fitted into a mounting hole formed in a substrate and heat caulked to fix the substrate and the attachment member.

Such a method, for example, as shown in Figure 1,
It is used to connect conductors of electrical parts, and a board 3 holding a cord 2 is disposed on a terminal base 1, and a tip 4a of a mounting member 4 is formed on the terminal base 1 from the bottom side in FIG. After fitting the hole 1a and the hole 3a formed in the substrate 3, it is placed on the fixed electrode 5, and the movable electrode 6 presses the tip 4a of the mounting member 4 to apply a current from the movable electrode 6 to the fixed electrode 5. The mounting member 4 is heated and softened, and the tip portion 4a of the mounting member 4 is spread over the upper surface of the substrate 3 as shown in FIG. 3, so that the substrate 3 and the mounting member 4 are fixed.

However, in this type of device, the board 3 is only prevented from coming off by the tip end 4a of the mounting member 4, and is prone to looseness. Furthermore, since the contact area between the board 3 and the mounting member 4 is small, when used as a conductor for electrical parts, the resistance of the contact portion is large, causing heat generation and poor conductivity due to backlash.

For this reason, as shown in Fig. 4, some solder material 7 is welded around the mounting member 4 using a soldering iron (not shown), but this method does not work until the board 3 and the mounting member 4 warm up. Since the solder material 7 does not weld, it takes a long time, and if soldering is completed before it is completely warmed up, the solder material 7 is only in contact with the board 3 and mounting member 4 and is not welded (commonly known as This type of solder was prone to looseness (also called potato solder). Further, since unnecessary solder material adheres to the head of the mounting member 4, a correspondingly large amount of solder material is required.

The present invention has been made in view of the above problems, and uses the heat generated in the mounting member during heat caulking to weld the solder material to the board and the mounting member, thereby reliably fixing the board and the mounting member, eliminating the occurrence of looseness, and making it possible to avoid post-processing. The present invention provides a heat caulking method that eliminates the need for soldering work.

The present invention will be described in more detail below with reference to embodiments shown in the drawings.

FIG. 5 is a cross-sectional view of essential parts showing one embodiment of the present invention. Reference numeral 11 indicates a terminal base for an ignition switch made of thermosetting resin, and the terminal base 11 has a recess 11a and a recess 11a A conventional mounting hole 11b is formed in the center of the holder. 12 is a cord with a lead wire 12a and a covering 12b
One side is connected to a substrate 13, which will be described later, and the other side is connected to various loads not specifically shown. The board 13 is provided with a mounting hole 13a, a lead wire gripping part 13b, and a cord gripping part 13c. Reference numeral 14 denotes a mounting member having a base 14a and a tip 14b protruding from the base 14a. The mounting member 14 is used as a fixed contact for a switch component, and a movable contact (not specifically shown) is in sliding contact with the bottom surface 14c of the base 14a. 15 is a fixed electrode, 16 is a movable electrode, and 17 is a ring-shaped solder material.

Next, the heat tightening method will be explained.

First, the tip 14b of the mounting member 14 is inserted into the mounting hole 11b formed in the terminal base 11 and the mounting hole 13a of the board 13, and the part of the tip 14b of the mounting member 14 that protrudes from the mounting hole 13a of the board 13 is inserted. A ring-shaped solder material 17 is fitted onto the top surface 15a of the fixed electrode 15 on the base 14 of the mounting member 14.
Place the lower surface 14c of a. Then the movable electrode 16
The upper surface 14d of the tip 14b of the mounting member 14
Press. When a current is passed between the movable electrode 16 and the fixed electrode 15 after a very short period of time has elapsed, the distal end 14b of the mounting member 14, especially the vicinity of the upper surface 14d that is in contact with the movable electrode 16, generates heat and reaches a high temperature. The heat melts the solder material 17 along the outer periphery 14e of the tip 14b of the mounting member 14. At almost the same time, the top surface 14 of the tip 14b of the mounting member 14
The area around d softens and is crushed by the pressing force of the movable electrode 16. That is, heat caulking is performed, but this heat caulking time is done in a very short time.
When the heat caulking is completed, the solder material 17 is inserted into the mounting hole 13a of the board 13 and the mounting member 14 as shown in FIG.
The solder material 17 easily penetrates into the gap 20 between the outer periphery 14e of the tip portion 14b and the welding area becomes wider, and the solder material 17 is melted by the heat generated by the mounting member 14, so that the solder material 17 is reliably attached to the tip portion of the mounting member 14. The mounting member 14 is welded to the outer circumference 14e of the mounting member 14b.
Since the tip end 14b of the board 14 becomes extremely hot, the temperature of the board 13 is also high enough to weld the solder material, so the mounting member 14 and the board 13 are securely fixed by the solder material 17. Therefore, contact resistance is also reduced, and conduction failure and heat generation do not occur. Further, since the movable electrode 16 prevents the solder material 17 from adhering to the upper surface 14d of the mounting member 14, the amount of solder material 17 is reduced accordingly.

It goes without saying that the solder material 17 may be attached to the upper surface of the mounting hole 13a of the substrate 13 in advance.

FIG. 6 shows another embodiment of the present invention, in which a thread-shaped solder material 19 supported by a solder holding part 18 is used instead of the ring-shaped solder material 17.
Mounting hole 11b of terminal base 11 and board 13
The distal end 14b of the mounting member 14 is inserted into the mounting hole 13a of the fixed electrode 15, and the movable electrode 16 is placed on the fixed electrode 15.
At the same time as pressing the upper surface 14d of the mounting member 14, the solder holding portion 18 moves to bring the tip of the solder material 19 into contact with the outer periphery 14e of the mounting member 14, and the movable electrode 16
When a current is applied to the fixed electrode 15, a predetermined amount of solder material 19 is sent out from the solder holding portion 18 almost at the same time, and the solder material 19 is reliably welded to the substrate 13 and the mounting member 14 as shown in FIG.

This embodiment is advantageous when heat staking is carried out using an automatic machine or the like, and since it is not necessary to provide solder material in advance, heat staking can be carried out in a much shorter time.

As is clear from the above description, according to the present invention, soldering is performed instantaneously using the heat generated during thermal caulking, so that soldering can be accomplished in a very short time. Moreover, since the solder material is firmly welded to the substrate and the mounting member, play is less likely to occur between the board and the mounting member. Furthermore, since unnecessary solder material does not adhere to the upper surface of the mounting member, the amount of solder material can be reduced.

[Brief explanation of drawings]

FIG. 1 is a plan view of the conventional embodiment, FIG. 2 is a cross-sectional view of the main part of the conventional embodiment showing the state of heat staking, and FIG. 3 is an enlarged sectional view of the main part of the conventional embodiment after heat staking.
FIG. 4 is an enlarged sectional view of the main part showing the soldered state of the conventional embodiment, FIG. 5 is a sectional view of the main part showing the heat caulking state of one embodiment of the present invention, and FIG. 6 is the other embodiment of the present invention. A sectional view of a main part showing a thermally caulked state of an example of
FIG. 7 is an enlarged sectional view of the main part after heat caulking according to the present invention. 1,11...terminal base, 2,12...
Cord, 3, 13... Board, 4, 14... Mounting member, 5, 15... Fixed electrode, 6, 16... Movable electrode, 17, 19... Solder material.

Claims (1)

[Claims] 1. Insert a conductive mounting member into the mounting hole formed on the board, place solder material around at least a portion of the periphery of the mounting hole on the board, heat swage the mounting member, and use the heat generated in the mounting member to solder the mounting member. A heat caulking method characterized by melting the solder material and welding the solder material to the board and the mounting member.