JPS5847832B2 - Manufacturing method of rod-shaped connector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a new and improved method of manufacturing a rod-shaped rubber connector, and more particularly to a rod-shaped rubber connector in which parallel conductive paths perpendicular to the longitudinal direction are formed on the surface of the rod-shaped rubber connector.

In recent years, interconnectors, which are used to connect circuit boards in various electrical and electronic devices, particularly to connect display devices such as LC, EC, LED, or plasma, and their driving circuit boards, have been developed with a longitudinal force on their surface. Rod-shaped rubber connectors in the form of perpendicular parallel conductive paths have come to be widely used in a state in which they are clamped and/or crimped between objects to be connected.

Conventionally, to manufacture this kind of rod-shaped rubber connector, parallel conductive paths made of conductive resin or conductive rubber material were formed on the surface of a flexible insulating film or sheet, and this film or sheet was separated. After laminating it with an uncured raw rubber sheet and curing it into one piece, it is cut into a rod-shaped body on a plane perpendicular to the parallel conductive paths, or parallel printed stripes made of conductive material are cut into a rod-shaped body. A so-called transfer sheet with a pattern applied thereto is placed in a cavity with a rectangular cross section of a compression mold, and then a rod-shaped body made of preformed uncured rubber is placed in the cavity and compression molded. This is done by removing the transfer sheet from the mold and finally peeling it off from the rod-shaped body to transfer and integrate the conductive parallel striped pattern onto the surface of the rod-shaped body.

However, although both of the above two methods are suitable for manufacturing rod-shaped connectors with a rectangular cross section, they have a major drawback in that they cannot be applied to the manufacture of rod-shaped connectors with other irregular cross sections. , it is difficult to obtain high dimensional accuracy because the rubber sheet inevitably undergoes compressive deformation, and the latter method has the trouble of having to pre-form a rod-shaped body with a rectangular cross section that will serve as the core material of the connector. However, this method was not fully satisfactory as a method for producing this kind of rod-shaped connector on an industrial scale.

The present invention relates to a new and improved method of manufacturing a rod-shaped rubber connector proposed in view of the disadvantages and drawbacks of the conventional method of manufacturing a rod-shaped connector, which includes at least one rubber connector extending linearly on a molding surface. A composite sheet-like body in which a film or sheet with parallel conductive paths made of a conductive resin or rubber material and an uncured rubber sheet are laminated is placed in a compression molding mold having a groove-like cavity. The composite sheet-like member is charged in a state in which the groove is perpendicular to the groove-like cavity, and when the mold is heated and pressurized, pressure is applied to the both sides of the cavity to the extent that the composite sheet-like member is substantially pressed. be.

The method of the present invention will be explained in detail below.

First, in the present invention, a composite sheet material that is a material for a rubber connector, that is, a composite sheet material in which a film or sheet with parallel conductive paths formed on the surface and an uncured rubber sheet are laminated and integrated, is prepared. However, it is created as follows.

That is, regarding the film or sheet with parallel conductive paths formed on the surface, for example, heat-resistant synthetic resin film or sheet such as polyimide, polyether, polyester, or these resins or thermosetting epoxy resin,
Conductive ink,
It is obtained by forming a parallel striped pattern using a paint by screen printing or offset printing, and then drying and curing or semi-curing the pattern with hot air.

The conductive ink and paint used here contain one or more known conductivity imparting agents such as carbon black, graphite, and metal powder, and silicone rubber, nitrile rubber, neoprene rubber, polyethylene terephthalate, or It is obtained by mixing and dispersing the modified product in a matrix made of one or more heat-resistant thermoplastic resins such as polyarylate resins and polyamide resins.

The sheet having parallel conductive paths in the present invention can also be obtained by laminating and integrating a sheet made of an insulating synthetic resin or synthetic rubber sheet and the conductive matrix to form a block-like body, and then slicing this thinly in the lamination direction. It can also be obtained by

The above-mentioned flexible sheet having parallel conductive paths on its surface is then laminated and integrated with an uncured rubber sheet in the presence of an appropriate adhesive and coupling if necessary to form a composite sheet. This uncured rubber sheet is made of known synthetic rubber materials such as silicone rubber, nitrile rubber, and neoprene rubber, in addition to a non-sulfur-based crosslinking agent or curing agent that does not lead to residue, as well as reinforcing fillers. , plasticizers, colorants, stabilizers, heat resistance improvers, foaming agents, thermal conductivity improvers,
An uncured rubber compound containing no known additives such as a coupling agent was prepared in a conventional manner.

During this lamination and integration, the parallel conductive paths may be placed inside or outside the overlapping surfaces, and when placed inside, the parallel conductive paths are partially buried in the insulating rubber layer and parallel to the working surface of the rod-shaped connector. The conductive path is exposed;
When the parallel conductive paths are placed on the outside, the parallel conductive paths are formed to slightly protrude from the surface of the connector after molding.

In addition, when manufacturing a connector using a composite sheet in which parallel conductive paths are printed on the surface of a flexible insulating film or sheet and the parallel conductive paths are laminated on the inside, the above The film or sheet is peeled off after the rod-shaped connector is formed, but if this film or sheet is peeled off just before the connector is used,
It can play the role of protecting parallel conductive paths.

The composite sheet-like body previously prepared as described above is then molded using a compression mold according to the present invention.

The compression molding mold used in the present invention usually consists of an upper mold and a lower mold, and the molding surfaces of both the upper and lower molds each have a plurality of molds that match the external shape of the rod-shaped rubber connector to be molded. Each of the cavities is carved in the shape of a parallel groove, and at least one of the upper mold or the lower mold of this mold is provided with parallel protrusions that act like push-cutting blades along both sides of each cavity that extends in the groove shape. or has an acute angle.

The composite sheet is charged into the compression mold in such a way that the parallel conductive paths of the composite sheet are orthogonal to the parallel groove-like cavities provided in the mold.

After loading the composite sheet into the compression mold,
When the mold is heated to a predetermined temperature and a predetermined pressing force is applied thereto, the uncured rubber layer of the composite sheet is filled into the parallel groove-like cavity and cured.

At this time, the flexible sheet having parallel conductive paths is deformed along the inner surface of the mold cavity according to the shape of the mold cavity, but the parallel conductive paths are not collapsed.

If the upper and lower molds are separated after compression molding is completed as described above, a hardened rod-shaped rubber connector can be obtained from each cavity arranged in parallel grooves. By controlling the ridges or acute angles on both sides of each cavity and applying pressure to the extent that the composite sheet material is not completely sheared and separated but is substantially pushed through with only one skin remaining, the rod-shaped rubber inside each cavity can be The connector can be peeled off from the mold cavity all at once in a sheet-like state.

Moreover, the sheet-like body thus obtained can be easily separated into individual rod-shaped rubber connectors.

It goes without saying that the product taken out from the compression molding mold is subjected to any necessary post-heat treatment.

Next, the present invention will be explained based on the accompanying drawings.

First, FIG. 1 is a cross-sectional view of a compression molding mold used in carrying out the method of the present invention, and this mold 1 consists of an upper mold 11 and a lower mold 12. Parallel groove-like cavities 2a, 2b, and 2a, each corresponding to the mold and corresponding to the cross-sectional shape of the desired rod-shaped connector, are provided.
... are engraved, and protruding portions 3, 3 are provided on each side of the parallel groove-like cavity 2a of the upper die 11.

Note that 4 in the figure is an overflow groove for raw rubber.

For compression molding, this compression molding mold 1 includes a flexible insulating sheet between the upper mold 11 and the lower mold 12 with the parallel conductive paths 51 inside, as shown in FIG. A composite sheet 5 formed by laminating a rubber sheet 52 and an uncured rubber sheet 53, or a composite sheet 5 formed by laminating a sheet 52 and an uncured rubber sheet 53 with the parallel conductive paths 51 on the outside, as shown in FIG. The material is prepared as shown in the figure and then compression molded under predetermined conditions.

After compression molding, a sheet-like product can be taken out from the mold as shown in FIG. 4, and the desired rod-shaped connector can be obtained by separating the products one by one.

At this time, it is of course possible to obtain rod-shaped connectors that are individually separated by the protrusion portions 3 by adjusting the suppression applied to the mold.

FIGS. 5a and 5b show typical embodiments of rod-shaped rubber connectors obtained by the present invention, and FIG. 5a is one manufactured using the composite sheet shown in FIG. 3,
FIG. 2b shows a product manufactured using the composite sheet shown in FIG. 2.

6 to 10 illustrate different embodiments of the rod-shaped connector 6 obtained by the method of the present invention.

Note that these connectors do not need to be straight along the longitudinal direction as shown in the drawings, but may be somewhat curved, or may be configured in the shape of a frame.

Further, FIGS. 11 to 15 illustrate how the rod-shaped connector is used, and FIG. 11 shows an example of how the connector shown in FIGS. 5 and 6 is used, and FIGS. 1
FIG. 5 shows an example of the use of the connectors shown in FIGS. 7 to 10, respectively.

Note that the arrows in the figure indicate the applied force direction of the pressing force or the pressure bonding force, and 7 and 8 indicate, for example, LC and EC, respectively.
, an LED or plasma display device and its driving circuit board.

Further, numeral 9 in FIG. 12 is a press-fitting jig provided with a mounting vault hole.

As explained above, the method of the present invention includes forming a plurality of parallel groove-like cavities on the molding surface, and providing protrusions or acute angle portions extending along both sides of the cavities on at least one of the upper mold or the lower mold. A composite sheet made of an uncured rubber sheet with parallel conductive paths formed on its surface is placed in a compression mold and compression molded.This allows for the production of a large number of rod-shaped connectors with high dimensional accuracy. can be obtained at one time, and rod-shaped connectors having irregular cross sections other than rectangular cross sections can also be manufactured extremely easily.
This method has great practical value as a method for producing this kind of rod-shaped connector on an industrial scale.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view illustrating the state in which a composite sheet-like material serving as a raw material is charged into a compression molding mold in carrying out the present invention, and FIGS. 2 and 3 are respectively FIG. 4 is an end view showing different aspects of the body, and FIG. 4 is a perspective view of a product molded with the mold shown in FIG. 1. FIGS. 5a and 5b and FIGS. 6 to 10 are perspective views showing different embodiments of the connector obtained by the present invention. 11 to 15 are perspective views illustrating how the connector shown in FIGS. 6 to 10 is used, respectively. 1... Compression molding mold, 11... Upper mold, 12... Lower mold, 2a, 2b... Cavity, 3...・Protrusions or acute angle parts, 4...
... Overflow groove, 5 ... Composite sheet-shaped body, 6 ... Connector 7, 8 ... Connected device, 9 ... Pressure welding jig .

Claims (1)

[Claims] 1. A film or sheet with parallel conductive paths made of a conductive resin or rubber material formed on the surface and an uncured rubber sheet are placed in a compression mold having at least one groove-like cavity extending linearly on the molding surface. The laminated composite sheet-like member is placed in a state in which the parallel conductive paths are orthogonal to the groove-like cavity, and the composite sheet-like member is substantially pressed out at both side edges of the cavity when the mold is heated and pressurized. A method for manufacturing a rod-shaped rubber connector characterized by applying pressure to a certain degree.