JPS599994A - Device for coupling substrate to electric terminal - 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 The present invention relates to a substrate-to-electrical terminal coupling device for electrically and mechanically coupling a substrate to an electrical terminal.

Conventionally, when connecting a power supply terminal (for example, a large capacity cable for power supply to a power supply bank board) to a printed circuit board, a common screw fastener was used to connect the two. FIG. 1 shows a conventional example.

The printed board 1 has electronic components 7 attached thereto, and electrical wiring is printed on its surface, thereby performing an electrical function as a printed board. The electronic component 7 is an IC
It may be a C circuit, a single electronic component, or a collection of single electronic components. On the other hand, printed board 1
A through hole 6 is provided in the. A layer 6A of conductive material is formed around the through hole 6, and serves as an electrical connection using the through hole. Through hole 6
B is electronic component 7 (however, the inside of part 7 is omitted from the drawing)
The vial 7A is inserted to fix the external vial 7A, and an electrical and mechanical connection is achieved by soldering.Other than these, various through holes exist in the printed board and are used.

The through hole 6 mechanically and electrically connects the electrical terminal 5 and the printed board 1 using a fastening metal fitting.

The fastening fitting consists of a bolt 2, a washer 3, and a nut 4, and an electrical terminal 5 is connected between the washer 3 and the bottom of the printed board 1.
, and firmly fasten the bolt 2 to the nut 4. As a result, the electrical terminal 5 is fixed to the printed board 1, and is brought into surface contact with the conductive layer 6A to achieve electrical connection. Pottery,
The inner diameter of the through hole 6 is approximately 3.5θ.

The connection of the electrical terminal to the printed board using such a fastener has the advantage of being a simple method, or if the printed board shrinks in the thickness direction over time, the connection between the bolt 2 and the nut 4 will deteriorate. . As a result, electrically, the contact area decreases, resulting in an electrically unstable connection, and mechanically, the υ coupling becomes unstable due to loosening.

SUMMARY OF THE INVENTION An object of the present invention is to provide a board-to-electrical terminal coupling device that electrically and mechanically strengthens the coupling between the board and the electrical terminals.

The gist of the present invention is not to bring the board and the electrical terminal into direct electrical contact, but to connect the board and the knurling of the metal fitting with solder, and then to join the knurling, the board, and the electrical terminal. The structure is such that screws can be fastened as required.

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

2 and 3 show examples of the screw fastening fitting part 9 of the present invention, FIG. 2 is a perspective view of the fastening fitting part 9, and FIG. 3 is a cross-sectional view taken along line AA' of the fastening fitting part 9. The fastening fitting part 9 consists of a head part 14 and a Lawson 10. The head portion 14 is circular (diameter φ3) and has a constant length 13. Lawson) 10 has many grooves 13 in the vertical direction for use with temples. The knurling 1o has a bottom hole 12 with a diameter of φ2 and a length of 12, and the head portion 14 has a hole 16 with a diameter of φ1, and a screw 8 is formed inside the head 14, which is the outer periphery of the hole 16. . The knurling lO has a constant thickness 14
have. In addition, the hole 16 does not pass through the head 14 and is a dead end (or may be sealed). A bolt is inserted into the hole 16. The surface 15 on the opposite side of the head portion 14 of the candle) 10 serves as a bottom contact portion. The candle (candle) 10 has two notches Hl around it in the vertical direction. This notch 11 is provided to improve solder breakage during solder connection. The knurling lO and the head portion 9 are integrally constructed.

FIG. 4 shows how such a fastener is attached to a printed board. (a) The figure is a cross-sectional view of the printed board l,
It has a through hole 6.6B. (b) In the figure, the fastening fitting part 9 shown in FIGS. 2 and 3 is inserted into the through hole 6, and seven bottles of electronic S products 7 are inserted into the through hole 6B. If the diameter of the through hole 6 is ψ, ψ2+”214=ψ, ・(
The relationship 1) holds true. Therefore, the candle 10 can be inserted into the through hole 6 in close contact with it. On the other hand, knurling 1
The vertical length is (however, 12>ls) of 0 is the same as the thickness lo of the printed board 1. ...(2). Furthermore, the diameter ψ3 of the head portion 14 is ψ3>ψ0
...(3). Therefore, even if the knurling 10 is inserted into the through hole, the end 14A of the head portion 14 plays the role of a brim, and the knurling 1
Only 0 is inserted into the through hole 6. Also, from equation (2), the length of the tip, which is part of the knurl 100', is 11
The portion lo) protrudes from the through hole 6 to the outside.

In the figure (c), soldering is performed with the fastening fitting part 9 inserted into the through hole 6 shown in figure (b) and with the bottle 7A of the electronic component 7 inserted into the through hole 6B. This soldering is performed on the back side of the printed circuit board 1, so that the conductive layer 6A of the through hole 6 and the contact area around the knurling 10 are soldered,
People are also made from soldering. 6D shows the formed soldering part. As a result, the fastening fitting part 9
and the printed board 1 are electrically connected and also mechanically coupled.

2) In the figure, the electrical terminal 5 to be connected is placed on the surface 15 of the fastening metal part 9 soldered to the through hole 6 shown in the figure (・), and then the washer 3 is Insert bolt 2 into. The bolt 2 is strongly screwed to the internally threaded υ portion 8 of the head portion 14 through the metal fitting bottom hole 12 of the knurling 10. As a result, one surface of the electrical terminal 5 comes into surface contact with the knurling 10, and the electrical terminal 5 and the printed circuit board 1 are joined together in an irregular manner. At the same time, since they are fastened by bolts 3, a 17 mechanical connection is achieved.

Fig. 5 shows an enlarged view of Fig. 3). The thickness of the conductive layer 6A is smaller than the thickness of the printed board 1. This conductive layer 6A
is formed by plating.

According to the fastener of this embodiment, electrical and mechanical connection between the printed board 1 and the electrical terminal 5 can be achieved. The specific effects at that time are listed below.

(1) Since the groove 13 is provided around the knurling 10 in the longitudinal direction of the knurling, the groove 13 is
The solder flows into the inside. Therefore, the conductive layer 6A and the candle 10 are firmly soldered.

(2) The surface 11 of the knurling 100 that forms an electrical connection with the electrical terminal 5 can have a larger contact area than the conventional example shown in FIG. In the conventional example, the contact area with the electrical terminal 5 is determined by the spread of the conductive layer 6A on the lower surface of the printed board 1.

However, this spread υ is small. In this embodiment, the contact area with the electric terminal 5 is determined by the extent (size) of the bottom contact portion 15 of the candle 10. The spread of this bottom surface contact portion 15 is larger than that of the conventional conductive layer 6A, and therefore a large contact area can be provided and a large current can be supplied. Furthermore, the electrical connection state becomes stable.

(3) The diameter of the bottom hole 12 of the metal fitting (candle) 10 is made larger than the diameter of the threaded part of the bolt 2 (ψ2〉ψI
). Furthermore, the tip end side of the bolt 2 of the hole 16 in the head portion 9 is closed. In this case, when soldering, the air does not escape upward through the hole 16, and ψ2〉ψ! Therefore, the solder is in the vicinity of the bottom contact portion 15 of the hole 12 and in the vicinity of the hole 1.
It attaches only to the second part. Thereby, it is possible to prevent solder from entering the threaded portion 8. In particular, when simultaneously soldering including bottle 7A using a soldering bath,
Preventing solder from entering the threaded portion 8 has the effect of significantly improving the reliability of soldering and eliminating obstacles to subsequent bolt fastening (r0 Furthermore, the notch portion (slit) 11 is provided). This has the advantage of eliminating solder breakage.

(4) The electrical terminal 5 is connected to the printed board 1 (or the conductive layer 6A)
Since the printed board 1 is not in direct contact with the printed board 1 but is in indirect contact via the knurling lO, it is not easily affected by the thickness shrinkage of the printed board 1 over time.

An experimental example for I-He's real sister is shown below.

Since one end of the hole 16 in the head portion 14 of the metal fitting 9 is a dead end (or may be sealed), solder would not adhere if the sill 12 provided at the bottom of the candle 10 was 6φ or less.

When the hole 12 was made larger than 6φ, solder could not be attached to the hole 12 even if one end of the hole 16 was open. Hole 12 like this
If the diameter of the hole 12 is made too large, even if solder is attached to the hole 12, when it leaves the solder tank, the surface tension of the solder will cause the solder to break around the hole 12 (the solder will break around the top of the hole □ 2
This is because the solder will not stick.

FIG. 6 is a diagram showing another embodiment of the fastening metal part. This embodiment has an effect in that the upper part of the hole 16 of the head 14 of the fastening fitting part 9 is opened, thereby making it easier to form the threaded p part 8. If the seal portion 20 is attached before soldering, the advantages in subsequent work and the advantages after attachment are the same as in the previous embodiment.

According to the present invention, it was possible to eliminate the adverse effects of electrical and mechanical coupling with electrical terminals due to thickness shrinkage of the printed board over time, and to obtain a stable coupling relationship.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the installation of a conventional fastening metal fitting, FIGS. 2 and 3 are illustrations of an embodiment of the fastening metal fitting of the present invention, and FIG. 4 (A). (b), (c), and (b) are views showing the installation process of the fastening fitting of the present invention, FIG. 5 is a partially enlarged view thereof, and FIG. 6 is a view of another embodiment. 9... Fastening metal part, lo... knurling, 11...
- Notch (slit), 12...hole, 13...groove, 14...head part. Agent: Patent Attorney Masamicha Akimoto / Diagram No. 2, No. 3, Kogure, No. 4

Claims (1)

[Claims] 1. In a board and electrical terminal coupling device in which an external electrical terminal is coupled to the board through a through-hole in the board using a conductive fastening fitting and a bolt, the fastening fitting is connected to the board through the through-hole in the board. A head portion having an outer diameter larger than the outer diameter and having a predetermined thickness in the axial direction, and a groove formed integrally on one surface side of the head portion and having a groove around the axial direction. , and a knurling having an outer diameter so as to fit closely into the through hole of the board, and a hole partially threaded from the end face opposite to the head of the knurling to the inside of the head. At the same time, tightly insert the knurling of the fastening metal part into the through hole of the board, insert an external electrical terminal on the end face opposite to the head part of the knurling, and insert the bolt into the hole formed by threading the 7 parts above. A device for connecting a board and an electrical terminal by inserting the bolt into the board and crimping and fixing an external electrical terminal using the bolt.