JPH04116374U - elastic connector - Google Patents

Abstract

(57) [Summary] (with amendments) [Purpose] Reduces the compressive load when pressing against the board and enables repeated use. [Structure] A plurality of spiral conductive wires 2 in an insulating elastic body 1
are buried in parallel while maintaining mutual insulation, and at least some of the conductive wires 2 have both ends exposed to the outside.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is designed to connect electrical circuit boards (hereinafter referred to as boards) and between display devices and drive circuit boards. This invention relates to elastic connectors used in

0002

[Conventional technology]

Conventionally, multiple straight conductive wires were buried in an insulating elastic body parallel to the thickness direction while maintaining insulation. The elastic connector installed is pressed into contact between the connection electrodes of the liquid crystal display device and the drive circuit, etc. However, the quality of the input and output electrodes on the board is improved by applying a high compressive load to the end face of the conductive wire. I was trying to make a good connection.

0003

[Problem that the idea aims to solve]

However, in the conventional elastic connector, the conductive wire may buckle or be repeatedly compressed. If the wires were repeatedly connected, they would cause poor conductivity, which could lead to further accidents such as wire breakage. this In order to prevent However, since the effective contact area of the conductive wire decreases during compression, the suitable load range is narrow. The disadvantage is that the thickness of the insulating elastic body and the buried pitch of the conductive wire are limited. there were.

0004

[Means to solve the problem]

The present invention solves the above-mentioned disadvantages. conductive wires are buried parallel to each other while keeping insulation from each other, and at least some of the conductive wires are buried at both ends. This is an elastic connector that is characterized by being exposed to the outside.

[0005] The elastic connector of the present invention will be explained below with reference to the drawings. Figures 1(a) and (b) As shown in FIG. The ends are buried parallel to the conduction direction at a constant pitch while maintaining insulation, and their ends are exposed to the outside. Gold plating 3 is applied to the surface to improve corrosion resistance and conductivity. In (c), the insulating part When using unvulcanized rubber 4 (vulcanized after pressure welding as necessary) as the material, A support layer 5 made of an elastic material is attached to the side surface of the nectar, and an unvulcanized rubber 4 It has the effect of preventing deformation. In Figs. 2(a), (b), and (c), Fig. 1(a) is used, respectively. ), (b), and (c) are buried in two rows, and in FIG. Regular spiral conduction is formed in the elastic elastic body 6 in grids (for example, 0.5 mm grid). The wires 2 are buried, and in FIGS. 4(a) and 4(b), they are buried randomly. Ma In Figures 5(a) and (b), the support layer 5 is pasted around the connector in Figure 2(c). It is matched. By forming the conductive wire buried in the insulating elastic body into a spiral shape, pressure can be increased. It prevents the conductive wire from buckling when compressed, withstands repeated use, and prevents the conductive wire from buckling when compressed. The end face is not inclined and the contact area between the electrode and the conductive wire is not reduced, so The suitable load range can be widened.

[0006]As the conductive wire itself used in the elastic connector of the present invention, gold, silver, and copper are desirable because they have low resistivity and are stable, but they have problems in terms of compressive strength and cost. In general, when connecting circuit boards or display devices such as liquid crystal displays and plasma displays, the effective load range of conductive wires is 0 to 0.3 kgf/ ^mm2 , so the maximum compression ratio during pressure welding connections is possible. Assuming 80%, it is sufficient to withstand a load of about 375 mgf/10% per piece, so various metal materials such as spring steel, molybdenum steel, nickel, and brass, and carbon fiber are suitable. Furthermore, in order to stabilize contact resistance and improve sulfurization, oxidation, and moisture resistance, it is desirable to gold plate the end surfaces of the conductive wires that are exposed to the outside and contact the input/output electrodes of the board to improve environmental resistance. .

[0007] In addition, various shapes of spirals can be selected and used depending on the purpose. However, in order to achieve low pitch and high parallelism, the average outer diameter should be 0.2 mm or less, and the wire diameter should be is preferably 0.08 mm or less, and the number of turns is at least 2 to maintain spring characteristics. It is preferable to set it as above. To form conductive wire into a spiral shape, molten metal is placed in a mold and formed. , a method of forming a metal wire by winding it around a rotating drum while moving it in the axial direction, and a method of forming two wires. There is a method in which the above conductive wires are entwined with each other to form a spiral shape, and then separated after baking. Fix both ends of the wire, rotate one end to form a spiral, and apply nitrogen, neon, or helium. After quenching in an inert gas such as Examples include methods such as opening the ends, but the spiral conductive wire used has a non-standard outer diameter and wire diameter. If it is always small, a method of intertwining two conductive wires is preferred.

[0008] As the insulating elastic body, a solid (non-foamed) elastomer is preferable. Silicone rubber with excellent compression set characteristics and electrical insulation properties for repeated use. is desirable, but rubber such as styrene-butadiene rubber (SBR), natural rubber (NBR) etc. Lastomers can also be used. In addition, the surrounding area of conventionally known unvulcanized rubber or gel rubber It can also be used by surrounding it with vulcanized rubber, in which case the compressive load of the elastic body itself is Weight can be reduced.

[0009] The insulating elastic body is made by extruding a rubber composition, which is the main material that makes up the known connector. Can be obtained in sheet or block form by combining injection molding, compression molding, etc. . Spiral conductive wires are embedded in an insulating elastic body in parallel and low-pitched arrays at equal intervals. In order to There is a method of winding the conductive wire around the pitch, and a method of keeping the spiral conductive wire arranged in the groove in the mold in advance. There is a method of injecting insulating rubber into a mold and compression molding after holding the mold. This is desirable because the dimensional accuracy of the groove spacing is high. Alternatively, place a spiral conductive wire in a jig of the same type as the mold used in the above method, and Unvulcanized rubber topped on a sheet of ethylene terephthalate (PET), etc. This spiral conductive wire is transferred onto the paper, and unvulcanized rubber is laminated on top of it and vulcanized. There is a way to do that. The results obtained by these methods are The end surface of the conductive part is made insulating by cutting it to a specified size, preferably at right angles. Obtain a connector exposed from the elastic body. In addition, the spiral shape obtained in this way The ends of the conductive wire should either protrude from the insulating rubber surface or be flush with it. However, if the protrusion is too large, the end may fall sideways during pressure welding. The material and shape of the spiral conductive wire should be It is preferable to appropriately combine the shape and type of insulating rubber. Width according to need and purpose , the length, etc. may be further cut into an arbitrary shape.

0010

[Effect]

The elastic connector of this invention is sandwiched between the input and output electrodes of the board to be connected, and the pressure is applied. When compressed, both ends of the exposed spiral conductive wire of the connector connect to both input and output electrodes. touch Since the conductive wire has a spiral shape, it connects both input and output electrodes by making elastic contact. , even after repeated compression use, the resistance value hardly changes. Also, gold plate the end face of the conductive wire. It is effective to improve the environmental resistance characteristics by coating.

[0011]

【Example】

The following spiral conductive wire and insulating elastic body were used in Examples 1 to 5. (a) Spiral conductive wire Two nickel wires with a diameter of 0.03 mm have a helical pitch of 0.05 mm. After wrapping and quenching in nitrogen gas at about 1,000℃, it is immersed in water. Rapid cooling, annealing in nitrogen gas at 400 to 500°C, then cooling and forming a spiral A spiral conductive wire with a spring constant of 225 mgf/10% was obtained by separating the conductive wire. . (b) Spiral conductive wire (a) Use a primer (KBM403 manufactured by Shin-Etsu Chemical Co., Ltd.) for the spiral conductive wire. (diluted with ethanol) for 5 minutes and baked at 180°C for 2 hours. (c) Insulating elastic body Silicone rubber KE151ku (manufactured by Shin-Etsu Chemical Co., Ltd., trade name) and vulcanizing agent C -2 (manufactured by Shin-Etsu Chemical Co., Ltd., trade name) is kneaded using a mixing roll. (d) Insulating elastic body Silicone rubber KE151ku (manufactured by Shin-Etsu Chemical Co., Ltd., trade name)

Example 1 The spiral conductive wire (A) with a length of 1.2 mm was placed in a mold groove formed at a depth of 0.05 mm with an interval of 0.2 mm, and the spiral conductive wire (A) was placed there. ) was injected using an extruder, compression molded by applying a pressure of 150 kg/cm ² at 180°C for 5 minutes, and then immersed in the primer for 15 minutes and molded at 180°C for 2 hours. By baking, a rubber sheet containing spiral conductive wires with a thickness of 0.4 mm was obtained. On this rubber sheet, a PET film topped with raw rubber to a thickness of 0.4 mm was laminated, the PET film was peeled off, and a separately prepared rubber sheet with spiral conductive wires similar to the above was placed on top of the PET film. They are pasted together to form a three-layer rubber sheet with a thickness of 1.2 mm, and this is vulcanized at 120° C. for 2 hours. Then, it was cut at right angles to the direction in which the spiral conductive wires were lined up to obtain a connector having the shape shown in FIGS. 2(a) and 2(b) (but without the gold plating 3). This connector was subjected to a compression cyclic test (compression ratio 20%) 100 times, and almost no increase in resistance was observed. However, as a comparative example, the same elastic connector was tested except that a conventional straight conductive wire was used. As a result, the resistance value increased as the number of repetitions increased, and continuity was broken after three repetitions.

[0013] Example 2 The unvulcanized insulating elastic was placed in a rectangular mold of 50 mm x 200 mm x 300 mm. The substance (c) is injected using an extruder, and the spiral shape of the above (a) is formed in a lattice shape with an interval of 0.5 mm. Insert a conductive wire, compression mold under the same conditions as Example 1, and apply primer for 30 minutes. The primer was baked at 180°C for 5 hours, and then The rubber block containing a spiral conductive wire was obtained by vulcanizing the rubber body. This is a spiral conductor. Slice it to a thickness of 2 mm perpendicular to the direction of the line, and cut it into the shape shown in Figure 3 (but with gold plating). A sheet-like connector (without key 3) was obtained. This connector is similar to Example 1. The test was repeated and the results were the same as in Example 1.

[0014] Example 3 5 kg of the unvulcanized insulating elastic body of the above (c) and the spiral of the above (b) with a length of 2 mm Knead 4 kg of shaped conductive wire for 10 minutes with a mixing roll to form a 2 mm thick sheet. After that, it was punched out into a square of 300 mm on a side, and then the spiral conductive wire contained in it was punched out. Conductive wires are exposed to a magnetic field for one hour so that a force of 10 kgf is applied to each conductive wire in the thickness direction. After oriented, this material was vulcanized at 120°C for 2 hours under normal pressure, and then the end face of the conductive wire was vulcanized. was gold-plated to obtain a sheet-like connector having the shape shown in FIGS. 4(a) and 4(b). child Repeated tests similar to those in Example 1 were conducted on the connector, but the results were the same as in Example 1. there were.

Example 4 The spiral conductive wire of (B) was placed in a jig of the same type as the mold used in Example 2, and the spiral conductive wire of (B) above was topped with the PET film to a thickness of 0.2 mm. (d) Press the silicone rubber sheet to transfer the spiral conductive wire onto the silicone rubber sheet. Then, to cover this spiral conductive wire, the same silicone rubber sheet (d) was pasted on top of another sheet (this will be referred to as (e)), and a thickness of 0.4 mm was placed between the two sheets. After interposing the silicone rubber sheet of (d) (hereinafter referred to as (f)), and then pasting the 0.5 mm x 5 mm x 300 mm sheet made of the above (c) on both sides of this (f). As shown in Fig. 5, a 0.5 mm thick sheet member made of the above (c) was provided on the side circumferential surface of the block body not involved in conduction, and this was compression molded at 180° C. and 150 kg/cm ² for 2 hours. After vulcanization, the end faces were plated with gold to obtain connectors having the shapes shown in FIGS. 5(a) and 5(b). When this connector was repeatedly tested in the same manner as in Example 1, the results were the same as in Example 1.

Example 5 The spiral conductive wire of (A) was placed in a jig of the same type as the mold used in Example 2, and the spiral conductive wire of (A) was topped on the PET film to a thickness of 0.3 mm. ) was transferred to a rubber sheet (300 mm x 300 mm), another rubber sheet (d) was attached to the surface where the conductive wires were exposed, and the sheet was passed through a pinch roller with a clearance of 0.3 mm. Then, it was cold pressed at a pressure of 6 kgf/cm ² , cut perpendicularly to the direction of the conductive wire to a width of 5 mm, and then vulcanized to obtain a connector having the shape shown in FIGS. 1(a) and 1(b). This connector was subjected to repeated tests similar to those in Example 1, and the results were the same as in Example 1. The resistance value-compressibility and load-compressibility relationship curves in Examples 4 and 5 are shown in FIGS. 6 and 7. This shows that in the connector of the present invention, the change in resistance value is extremely small even if the compression ratio changes greatly.

[0017]

[Effect of the idea]

Due to the spring characteristics of the helical conductive wire, the elastic connector of the present invention has a relatively high compression It does not buckle even when subjected to a lot of damage, makes contact with the input/output electrodes of the board with low resistance, and can be used many times. It can withstand heavy use.

[Brief explanation of the drawing]

FIG. 1 (a) is a perspective view of the block-shaped elastic connector of the present invention, (b) is an explanatory diagram of the state in which the spiral conductive wire is embedded in the insulating elastic body in the connector of (a),
(c) is an explanatory diagram when a support layer is bonded to the connectors of (a) and (b).

FIG. 2 (a) is a perspective view of a block-shaped elastic connector according to another example of the present invention, and (b) is an explanatory diagram of the state in which the spiral conductive wire is buried in an insulating elastic body in the connector of (a). It is. (c) is an explanatory diagram when a support layer is bonded to the connector of (b).

FIG. 3 is a perspective view of a sheet-like elastic connector in which spiral conductive wires are regularly embedded according to the present invention.

FIG. 4(a) is a perspective view of a sheet-like elastic connector in which spiral conductive wires of the present invention are randomly embedded;
(b) is an explanatory view of the state in which the spiral conductive wire is embedded in the insulating elastic rubber in the connector of (a).

[Fig. 5] (a) is a perspective view of a block-shaped elastic connector of the present invention surrounded by a support layer, and (b) is a perspective view of the helical conductive wire embedded in the insulating elastic material in the connector of (a). It is an explanatory diagram of a state.

FIG. 6 is a relationship curve diagram between compression ratio and compression force in Examples 1 and 4 and a comparative example.

FIG. 7 is a relationship curve diagram between compression ratio and resistance value in Examples 1 and 4 and a comparative example.

[Explanation of symbols]

1 Block-shaped insulating elastic body 2 Spiral conductive wire 3 Gold plating 4 Unvulcanized (gel-like) rubber 5 Support layer 6 Sheet-like insulating elastic body

Claims (1)

[Scope of utility model registration request] Claim 1: A plurality of spiral conductive wires are buried in parallel in an insulating elastic body while maintaining mutual insulation, and at least some of the conductive wires have both ends exposed to the outside. elastic connector.