JPS6342380B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to electrical connectors, and more particularly to electrical connectors for making connections to flat surface contact areas on printed wiring boards, liquid crystal display devices, and the like.

BACKGROUND OF THE INVENTION In the field of electronic manufacturing technology, it has been a long-standing and difficult problem to provide printed wiring boards or liquid crystal display devices with interconnects that can withstand the shocks and vibrations applied during manufacturing and use. A typical printed wiring board has an insulating substrate with various electrical and electronic components mounted thereon, and all interconnections between the electrical and electronic components are wires and/or leads deposited on the substrate. This is done using lines. Terminals for interconnecting such printed wiring boards with other devices are constructed with a plurality of flat-surfaced pads or lands formed along one or more edges of the board.

Conventional connectors for interconnecting terminals on such boards are constructed with a plurality of metal spring-like members that are crimped to the edges of the wiring board to make effective contact with the terminal pads by elastic action. ing. These spring metal connectors do not completely satisfy the requirements from various points of view. That is, first, the connection with the terminal pad tends to become loose. This is primarily because such connectors usually have means for providing a large number of connections (for example, it is not uncommon to have as many as 40 connections), so the spring pressure applied to the individual contacts must be relatively low. Depends on what happens. That is, the spring pressure on the individual contacts must be low in order to keep the overall magnitude of the connector insertion force within a manageable range. It is not uncommon for one or more of a connector's spring contacts to bend during manufacturing or assembly, creating a bad or "high resistance" connection, both of which are undesirable. It is.

In order to achieve a good and reliable connection using spring connectors, epoxy or other suitable adhesives may be used to secure these connectors in place. However, in this way it is not possible to remove the connector without substantial risk of destroying either the connector or the wiring board, or both.

An electrical connector according to the present invention includes a flexible insulating strip and a plurality of flexible insulating strips extending and bonded in spaced relation to each other on a flat surface of the insulating strip. It is equipped with a conductor strip. The conductor strips have a number and arrangement corresponding to a plurality of terminal pads provided on a printed wiring board, for example, so that the conductor strips can be connected to the terminal pads. The surface of the conductor strip is covered with a conductive adhesive layer, and the remaining part on the flat surface of the insulating strip, that is, the area between the conductor strips, is covered with an insulating adhesive layer, so that One entire side of the connector is covered with a layer of conductive and insulating adhesive.

During use, one end of the connector is pressed onto a substrate, such as a printed wiring board, on which terminal pads are provided, so that each conductor strip is bonded to the conductive adhesive layer in one-to-one correspondence with the terminal pad on the substrate. connected via. The other portion of the connector is then pressed onto a set of terminal pads, such as on another wiring board, the electrical circuit of another piece of equipment, or another component.

More specifically, the flexible insulating strip of the present invention can be bent in the width direction.
Made of thin film or cloth material that is not an elastomer. Further, the conductive adhesive layer covering the surface of the conductor strip is provided over the entire length of the conductor strip so that the adhesive layer can be formed at any point along the length direction of the conductor strip. I would like to draw your attention to this.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, a preferred embodiment of the present invention will now be described in detail. FIG. The printed wiring board 10 is a generally rectangular insulating substrate on which microcircuits, individual components, etc., shown schematically at 12, are mounted and interconnected to form a desired circuit. 11. Printed wiring board 10 typically includes a plurality of deposited conductive pads 13 arranged along the edge of the board and having a flat surface.
It is interconnected to other wiring boards or other electrical devices through terminals consisting of. These pads 13 or lands can be formed by various known methods such as silix screen method and vacuum deposition.
Substrate 11 is constructed of glass, ceramic, or other material with good insulation properties and sufficient rigidity to be used as a circuit board. Although interconnections can be made between the printed wiring board 10 and various other electrical devices, in the following, for convenience of explanation, the board 11 is mounted.
A liquid crystal display element 14 having a set of connection pads 15 arranged at one edge with the same spacing as the pads 13
A case will be described in which the connector according to the present invention is used to connect to the computer. It should be noted that the pad 13 on the wiring board 10 has a step difference with respect to the pad 15 on the liquid crystal display element 14 because a right-angled step 16 is interposed therebetween.

Still referring to FIGS. 2 and 3, connector 17 includes a generally rectangular strip 18 formed of a highly flexible insulating material, such as fabric. The strip 18 is made of a thin non-elastomeric film or cloth that can be bent in the width direction. Disposed on the major surface of strip 18 are a plurality of elongated, generally parallel conductor strips 20 extending in spaced relation to each other completely across the narrow width of strip 18. . In particular, as will be described later, even if the connector 17 is bent as a whole, bent at an acute angle, or subjected to various deformations during use, the conductive properties of the conductor 20 will not be lost or substantially impaired. As shown, conductor strip 2
Preferably, 0 is flexible. The surface of the conductor strip 20 is covered with a conductive adhesive layer 21. Further, the remaining portion on the main surface of the strip 18, that is, the portion between the conductor strips 20 is covered with an insulating adhesive layer 19.
The entire area of one side of the connector 17 is covered with alternating conductive adhesive layers 21.
and an insulating adhesive layer 19 to form a flat adhesive surface that is generally parallel to the flat surface of the strip 18 as a whole.

In this case, the conductive adhesive is provided over the entire length of the conductor strip 20 so that an adhesive layer can be formed at any point along the length of the conductor strip 20.

In use, the connector 17 described above is placed on the printed wiring board 10 with a portion of the connector 17 overlying the set of terminal pads 13. Pressure is then applied on the connector 17 to electrically connect the conductor strip 20 to the corresponding pad 13 via the conductive adhesive layer 21, and the insulating adhesive layer 19 connects the strip 18 to the pad 13. It is fixed to a non-conductive substrate 11 existing between and near the substrate. The connector 17 is then shaped to fit over the step 16 in order to adhesively contact the edge of the substrate 11 and the portion of the display element 14 directly adjacent thereto.

Finally, the other part of the connector 17 is connected to the display element 14.
It is pressed against the upper pad 15, thereby making the desired interconnection between each pair of pads 13,15. When this final operational relationship is maintained, as shown in FIGS. 1 and 3, the connector 17 is bonded via the insulating adhesive layer 19 and the conductive adhesive layer 21. It is fixed across the pad 13 of the substrate 11, the pad 15 of the display element 14, and the insulating parts in their vicinity. If it becomes necessary to remove the connector 17, it can be easily peeled off without damaging the underlying pads or the board, and can be replaced with the same connector or another new connector. can be applied in the same way.

Although other materials may be useful, cloth or fabric is best for constructing the connector substrate (strip 18) in that it will not fail even with repeated or extreme bending or deformation. it is conceivable that.
Additionally, the fabric may undergo permanent deformation (a type of (as seen in plastic materials) does not occur. As an alternative material for this purpose, a flexible plastic such as Mylar and which can be coated with an adhesive may prove suitable.

An excellent material for producing conductor strips 20 that have both conductive and adhesive properties is a silver-filled polymer manufactured and sold by Emerson & Cumming, Inc., Canton, Mass., USA. This electrically conductive adhesive has good electrical conductivity and is resilient and flexible, maintaining the same surface thickness and electrically conductive adhesive properties after being applied for the above-mentioned purpose. Using such materials, conductor 20 may be formed by a variety of different methods, such as silk screening, brushing, roller coating, spraying or dipping, all of which are well known manufacturing techniques. The conductor 20 made of this material allows the final product on which the conductor strip 20 is provided to be produced without damaging the conductor strip 20 or peeling off from the substrate on which the conductor strip 20 is provided. It is important to emphasize that it has a high degree of flexibility to allow it to be substantially deformed.

An alternative that may be used to fabricate the conductor strips 20 is Micro Circuits, New York, Michigan, USA.
There is a silver paint sold by the Company under the trade name SC18-0.04, which consists of silver particles dispersed in elastic rubber. A resilient conductive epoxy resin, also available from the aforementioned Micro Circuits Company, can be applied directly onto these conductor strips 20 to form the desired conductive adhesive layer 21.

The present invention provides a connector that quickly and easily achieves interconnection between terminals and is inexpensive and simple to manufacture. It is also an advantage of the connector according to the invention as described above that it can be easily adapted to irregularities in the surfaces or configurations of the circuit devices to be interconnected, without requiring any changes in shape, structure or mode of operation of the connector. It is possible to do so. For example, if two wiring boards to be interconnected are placed at a 90° angle to each other, the same connector strip can be used, and the inherent flexibility of the strip It easily accommodates 90° bending without any loss of function or operation.

As mentioned above, connector 17 can be manufactured individually depending on the desired final dimensions;
The connector strips are produced in the form of large rectangular sheets 22 with conductors extending parallel along their longitudinal edges, allowing for the desired separation if it is desired to provide individual connectors. A number of connectors are simply cut off from one end of the sheet 22 (see FIG. 2). Sheet 22 can be rolled into rolls 23 for ease of storage and use, if desired. Preferably, the sheet 22 has conductor strips 2
0 and is provided with an insulating protective layer 24 which is applied over the connector and which can be removed when the connector is used.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a state in which the connector of the present invention interconnects a wiring board and other devices, FIG. 2 is an enlarged plan view of the connector according to the present invention, and FIG. 4 is a perspective view of the connector rolled up on a roll; FIG. 5 is a perspective view of the connector strip cut from the roll shown in FIG. 4; FIG. The figure is a partial cross-sectional view taken along line 6-6 in FIG. In the figure, 10 is a printed wiring board, 11 is a substrate, 13 and 15 are pads, 14 is a liquid crystal display element,
16 is a step, 17 is a connector, 18 is a strip, 19
20 is an insulating adhesive layer, 20 is a conductor strip, 21 is a conductive adhesive layer, 22 is a sheet, 23 is a roll, and 24 is an insulating protective layer.

Claims (1)

Claims: 1. A multi-lead electrical connector for interconnecting matched pairs of relatively flat conductive pads comprising: a thin insulating strip in the form of a film or cloth; a plurality of flexible conductor strips extending and bonded in spaced relation to the flat surface of the insulating strip; a conductive adhesive layer covering each surface of the conductor strip and provided over the entire length of the conductor strip so that an adhesive layer can be formed at any point along the length direction of the conductor strip; a conductive adhesive layer adapted to form an electrical connection between the conductor strip and a substrate to which the connector is bonded via the layer; and a flat surface of the insulating strip. an insulating adhesive layer covering a portion between the conductor strips on the top and maintaining lateral electrical insulation between the conductor strips, the conductive adhesive layer and the insulating The adhesive layer cooperates to cover the entire area of the connector, provides electrical conduction, and is capable of adhering the connector to the entire area of the board onto which the connector is pressed. electrical connector. 2. The electrical connector according to claim 1, wherein the insulating strip is fabric. 3. The electrical connector according to claim 1 or 2, wherein the conductor strip is made of conductive rubber in which silver metal particles are dispersed. 4. The electrical connector according to claim 1 or 2, wherein the conductive adhesive layer is a conductive epoxy resin. 5. The electrical connector according to claim 1, wherein the electrical connector is bonded onto the conductive adhesive layer and the insulating adhesive layer, and the electrical connector is bonded to the conductive adhesive layer and the insulating adhesive layer prior to use. The electrical connector further comprises a removable protective layer that can be peeled off from the adhesive layer. 6. The electrical connector according to claim 1, wherein the conductor strip is made of a metal-filled polymer having an electrically conductive and bondable outer surface. said electrical connector.