JPH0656774B2 - Contact for mounting printed wiring board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a printed wiring for directly attaching to a lead insertion hole of an electronic component or the like provided on a printed wiring board to cause a function of a socket and the like. The present invention relates to a plate mounting contact.

[Conventional technology]

Conventionally, in order to detachably mount electronic components on a printed wiring board (hereinafter, referred to as PCB), an integrated circuit (hereinafter, referred to as IC)
Abbreviated), various types of dedicated sockets for transistors, relays, etc. are used. These sockets are for PC
It is provided for the purpose of easily removing the electronic component from B or the circuit board without melting the solder. When developing electronic devices, these sockets are often used for new products with uncertain development factors. When mounting read-only ICs (hereinafter abbreviated as ROM), dedicated IC sockets are used. Often.

FIG. 3 shows, for example, the magazine “Transistor Technology” (1989).
FIG. 1A is a partially enlarged perspective view showing a conventional IC socket described in the Aug. issue, p. 141) and a plan view of a main part, in which FIG. A large number of IC lead insertion holes arranged in the main body 1,
2 is a tulip-shaped connecting portion which is inserted into the IC lead insertion hole 11 and which has four contact points 12a at its tip portion;
Reference numeral b is a connection lead integrally derived from the connection portion 12.

In FIG. 2B, 13 is an IC lead inserted in the IC lead insertion hole 11, and the four contacts 12a are in contact with each other.

Next, the operation will be described.

Each of the many IC leads 13 provided on the IC
When inserted into the lead insertion hole 11, as shown in FIG. 3B, the IC lead 13 is surrounded by the four contact points 12a and elastically contacts, so that an electrical and mechanical connection is obtained. Further, since the IC lead 13 can be easily pulled out, the IC can be attached / detached to / from the same socket many times. The connection lead 12b is inserted into the lead insertion hole of the PCB.

FIGS. 4, 5, and 6 show another embodiment of the connecting portion used in the conventional connector.
4, 15 and 16 are connection parts, 14a, 15a and 16a are contacts, and 14b, 15b and 16b are connection leads.

According to the above configuration, an IC lead (not shown) is inserted from the direction of the arrow and brought into contact with each of the contacts 14a, 15a, 16a, whereby electrical and mechanical connection can be obtained.

[Problems to be Solved by the Invention]

Since conventional sockets such as IC sockets are configured as described above, 1. Long-term contact stability cannot be guaranteed.

2. The use of sockets increases the mounting height and tends to impair high-density mounting.

3. If the weight of electronic components is relatively heavy, it is necessary to provide a fall prevention clamp.

4. In many cases, dissimilar metals come into contact with each other in nature, and there is a danger of functional deterioration due to electrolytic corrosion.

There are drawbacks such as. In particular, the above item 4 is often encountered when exposed to a hot and humid environment. Therefore, in the case of long-term reliability, it is unavoidable to stop using the socket and mount the electronic component directly on the PCB. . Also, with an IC having a large number of leads that are once soldered to the PCB, the removal work is not very easy, and connection with the through holes (holes for lead insertion) provided in the IC or PCB,
Alternatively, there are many accidents that destroy the wiring pattern and the like, and even if it seems that the wiring was successful, there is still a risk of impairing the reliability. As described above, in the conventional socket, even though the connection lead of the socket is inserted into the PCB or the like and soldered, there is little contact between the lead of the electronic component and the socket in order to maintain electrical contact. Since it depends only on the area and the function of elastic pressure, there are problems such as poor reliability.

The present invention has been made to solve the above problems, and is mounted in a lead insertion hole of an electronic component provided on a PCB, and an electrode (hereinafter referred to as a land) provided around the lead insertion hole. The purpose is to obtain a printed wiring board mounting contact that can be welded (soldered) with.

[Means for Solving the Problems]

The contact for mounting a printed wiring board according to the present invention is made of a thin metal plate as a base material, and has a connecting portion having a shape and size similar to those of the land and a branch from a substantially center of the connecting portion and bent in a direction at a right angle. The elongated portion, the bent portion that bends the elongated portion into a substantially V shape, and the hook portion in which the tip portion thereof is further bent in a substantially right angle direction are provided.

[Work]

The elongated portion in the present invention is inserted into the lead insertion hole of the PCB, the connecting portion is soldered to the land of the PCB, and the lead of the electronic component inserted into the lead insertion hole is bent to the bent portion. The parts are elastically contacted with each other, and the hooks are engaged with the ends of the lead insertion holes to prevent them from coming off.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 is a contact for mounting a printed wiring board according to the present invention (hereinafter referred to as a contact) having a thickness of about 0.
A metal thin plate having elasticity of 15 mm or less such as phosphor bronze plated with gold is integrally formed as a base material. 1A is a connection part having a diameter of about 1.3 to 3 mm, which is a PCB
It has a shape and dimensions similar to those of the circular land.
Reference numeral 1B is a slit provided in the connecting portion 1A, 1C is a slender elongated portion having a predetermined width d that is bent substantially vertically from a position slightly displaced from the center of the connecting portion 1A and further folded back to extend, and 1D is an elongated portion. The knob portion is formed so as to project when the strip portion 1C is folded back.

Reference numeral 1E is a positioning portion that extends straight from the knob portion 1D of the elongated portion 1C, 1F is a bending portion that bends the elongated portion 1C into a V shape after the positioning portion 1E, and 1G is an elongated portion 1
A hook portion 1H in which the tip end portion of C is formed in a substantially L shape is a thin mark for separating from the adjacent one which occurs when the contact 1 is mass-produced by a molding die, and a slight straight line portion remains.

Fig. 2 shows the contact 1 mounted on the PCB and the DIP
FIG. 3 is an enlarged side view showing a state in which a (Dual Inline Package) type IC is attached. In FIG. 2, 2 is an IC, 3 is an IC lead of IC2, 4 is a printed wiring board, and 5 is a printed wiring board. Is a circular land provided on the printed wiring board 4, 6 is a lead insertion hole provided corresponding to the land 5 on the printed wiring board 4, and 7 is a solder which is eluted into the lead insertion hole 6 and to the outside. . The thickness t (about 1.6 to 2 mm) of the printed wiring board 4 is equal to the length t from the connecting portion 1A of the elongated portion 1C to immediately before the hook portion 1G in FIG. The diameter φ of the lead insertion hole 6 is equal to the height φ generated by the bent portion 1F of the elongated portion 1C.

Next, the operation will be described.

A solder flux (hereinafter, referred to as flux) is previously applied to the land surface of the PCB on which the IC 2 is to be attached. The contact 1 is inserted into the lead insertion hole 6 from the surface provided with the land, which is opposite to that shown in FIG. 2 when the land 5 has only one side, as shown in FIG. As a result, the positioning portion 1E comes into contact with the inner wall of the lead insertion hole 6 to position the contact 1, and the hook portion 1G projects from the side opposite to the insertion side of the lead insertion hole 6 and its end By engaging with, the contact 1 is prevented from coming off, and the contact 1 is temporarily fixed. The contact 1 may be inserted into the lead insertion hole 6 while holding the grip portion 1D by hand or with a suitable jig. Next, the slit 1 of the connecting portion 1A
The lead 3 of the IC 2 is inserted into the lead insertion hole 6 from B. After that, when the solder is heated from the connection portion 1A side with a soldering iron or a heating tool equivalent thereto, the flux on the PCB land 5 and the solder of the connection portion 1A are fused, and the solder 7 is eluted as shown in FIG. Then, they will be welded electrically and mechanically.

Then, by the same means, contact 1 as many as IC leads 3
The IC2 can be mounted on the PCB by mounting the IC2 on the PCB. Since the contact 1 is extremely small, workability is improved by using, for example, an insertion jig having a vacuum suction function.

According to the above, when confirming the performance compatibility between the PCB and the IC under development, or confirming the ROM writing data, the number of times of inserting and removing the IC is usually about 2 to 3 times. If there is no change thereafter, this socket has a structure that can be surely connected by the soldering process, so that long-term reliability is dramatically improved compared to the conventional PCB with the socket left. It is certain to improve.

Although the above embodiments have been described with reference to the DIP type IC and the circular land of the PCB, the present invention can be applied to rectangular, rectangular, and other modified lands, and also to contacts in addition to transistors, relays, and the like. Needless to say, the same function can be achieved by using the shape and size in consideration.

Further, the contact 1 has not only the socket function described above,
When it is necessary to connect the wiring pattern between the front and back of the PCB, the PCB without the step of plating inside the lead insertion hole
It is possible to effectively utilize it for manufacturing a board and connecting the front and back sides with eyelets or the like, or for repairing a PCB in which the land is peeled off.

〔The invention's effect〕

As described above, the present invention has a configuration in which the connecting portion, the elongated portion, the bent portion, the hook portion, and the like are integrally molded using the thin metal plate, so that it can be mass-produced inexpensively by the molding die, and the parts described at the beginning. The mounting height of P does not substantially change, and it does not impair high-density mounting.
It is also possible to apply the CB without modification, and even if the dissimilar metals may come into contact at the beginning, the unstable state can be finally solved by the soldering process, so that the reliability of the CB can be improved. There are advantages such as high electrical and mechanical connection.

[Brief description of drawings]

1 is a plan view, a side view and a front view showing a contact for mounting a printed wiring board according to an embodiment of the present invention, and FIG. 2 is a side view showing a state in which the contact is mounted on a printed wiring board together with an IC. FIG. 3 is a partially enlarged perspective view showing a conventional IC socket and a plan view of an essential part, and FIGS. 4, 5, and 6 are front views showing examples of connection parts used in the conventional socket.
It is a side view and a rear view. 1 is a contact for mounting a printed wiring board, 1A is a connecting portion, and 1C
Is an elongated part, 1F is a bent part, and 1G is a hook part. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A connecting portion made of a thin metal plate having a shape and dimensions similar to those of a land on a printed wiring board, and an elongated portion integrally extending vertically from substantially the center of the connecting portion.
A contact for mounting a printed wiring board, comprising: a bent portion that bends the elongated portion into a substantially V shape, and a hook portion that is formed by bending a tip of the elongated portion into a substantially L shape.