JPS61248310A - Connection of lead to switch structure body - 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 (Industrial Field of Application) The present invention relates to connection of lead wires to a switch structure mainly made of pressurized conductive rubber, whose resistance value rapidly decreases due to the action of a pressurizing force of a predetermined value or more. In particular, the present invention relates to a method for connecting a lead wire without causing poor insulation or poor conduction.

(Prior Art) A switch structure in which a pair of flexible electrodes are arranged with a pressurized conductive rubber spaced apart and covered with an insulating elastic outer cover is disclosed, for example, in Japanese Patent Application No. 129172/1982. It has been confirmed that this manufacturing technique can be manufactured continuously and efficiently using a technology that provides switch structures of various sizes and shapes with appropriate operating characteristics. It is possible.

That is, here, as shown in FIG. 3(a), a pair of flexible electrodes are sandwiched between a pressurized conductive rubber 1 made of, for example, silicone rubber mixed with metal powder or other conductive particles. The flat braided wires 2.3 are introduced into the chaping machine 4, and in the vicinity of the inlet, the flat braided wires 2.3 are expanded around the support shaft 5, and the pressurized conductive rubber 1. While blowing air between the flat braided wires 2 and 3, the whole is pulled in the direction of the nozzle 6, while extruding an insulating elastic outer covering material made of silicone rubber into a tubular shape with the tubing machine 4, and passing it through the nozzle 6. A conductor consisting of pressurized conductive rubber 1 and flat braided wires 2 and 3 is coated to form an elastic outer skin 7. As a result, both ends of the pressurized conductive rubber 1 are welded to the inner wall of the outer sheath 7, the outer part of the hand-knitted wire 2.3 bites into the outer sheath 7, and the pressurized conductive rubber 1 and the flat knitted wire 2.3 are bonded together. A switch assembly as shown in FIG. 3 is produced in which there is an air gap 8.9.

Therefore, according to this manufacturing method, the pressurized conductive rubber 1 and the flat braided wire 2.3 as electrodes are always arranged in a proper positional relationship, and a long switch structure with high reliability in operating characteristics can be manufactured. I can do it.

Here, if the opening of the nozzle 6 is narrowed and the elastic outer covering material is extruded without blowing air, the reliability can be improved with the flat braided wires 2 and 3 in contact with the opposing sides of the pressurized conductive rubber 1. It is possible to build tall and long switch structures.

On the other hand, since the technology for mechanically manufacturing particularly short switch structures using pressurized conductive rubber has not yet been established, such switch structures can be made using hand-knitted wire, wire mesh, Tokyo Dodo, etc. A flexible conductor such as a wire or a conductive elastomer film is cut to a predetermined size to make an electrode, and a pressurized conductive rubber, which has also been cut to a predetermined size, is sandwiched between the electrodes from the opposite side. , it is common to manually produce them by coating them with an insulating elastic outer skin, and small pressurized conductive switches made by connecting lead wires to such a switch structure are made of pressurized conductive rubber. It is manufactured by connecting lead wires to the electrodes before sandwiching them.

(Problem to be Solved by the Invention) For this reason, in the conventional short switch structure, and even in the case of a small pressurized conductive switch with a lead wire connected thereto, it is particularly important to use pressurized conductive rubber and electrodes. When covering with an elastic outer cover, it is extremely difficult to properly maintain the pressurized conductive rubber and both electrodes in the specified position, and if their relative positions are displaced from the proper position, the insulating elastic The outer skin may enter between the pressurized conductive rubber and the electrode, resulting in poor continuity of the pressurized conductive switch.In addition, the operating characteristics of the pressurized conductive switch may be affected by the fact that the pair of electrodes do not face each other accurately. There were problems such as differences depending on the location of the external force.

On the other hand, when cut pieces of plain braided wire, wire mesh, Todo wire, etc. are used as electrodes, the conductive wires tend to come loose at the cut parts, and these loose conductive wires separate the pressurized conductive rubber. There was a problem in that the pressurized conductive switch would come into contact with the other opposing electrode, resulting in a short circuit of the pressurized conductive switch.

An object of the present invention is to cut a long switch structure to a predetermined length, which is manufactured based on established manufacturing technology, and in which a pressurized conductive rubber and an electrode are arranged in an appropriate positional relationship. By cutting the outer skin at a predetermined position and connecting the lead wire without cutting or cutting, we can efficiently create a highly reliable pressurized conductive switch with no risk of poor continuity or insulation. The purpose is to provide a method for manufacturing.

The present invention advantageously solves problems such as conduction defects and insulation defects that occur not only when manufacturing short pressurized conductive switches but also when connecting lead wires to long switch structures.

(Means for Solving the Problems) In order to achieve this object, the method for connecting lead wires to the switch structure of the present invention includes a pressurized conductive rubber and a pair of flexible conductive rubbers placed apart from each other. For example, the elastic outer cover of the switch structure in which the elastic electrode is coated with an insulating elastic outer cover is removed using a specially prepared stripper or the like.
partially exposing each electrode by locally cutting; connecting a lead wire to each exposed electrode; and insulating at least the exposed electrode portion and the connection portion of the lead wire thereto. The process of sequentially combining the steps of covering with a soft elastic outer skin.

(Function) According to this method, the manufacturing technology for the long switch structure as a starting material has already been established, and in the switch structure, the pressurized conductive rubber and the electrode are always maintained in a predetermined positional relationship. Therefore, regardless of whether or not the length is shortened afterwards, problems caused by fluctuations in the relative position between the pressurized conductive rubber and the electrode will not occur, and By locally cutting off the outer skin portion corresponding to the electrode portion to which the lead wire is to be connected, the predetermined portion of the electrode can be removed without causing any loosening of the electrode previously embedded within the elastic outer skin, especially at its end portions. can be exposed with certainty.

Note that such removal of the outer skin part can be done, for example, by fixing the switch structure, making a cut in a size that corresponds to the required dimensions of the cut part, and then grasping the cut part and peeling it off. This work can be carried out reliably and extremely easily without causing any damage to the rubber or electrodes.

Further, since this removal of the outer skin is performed only on the portion corresponding to the electrode site to which the lead wire is to be connected, the function of the remaining portion of the outer skin is not affected in any way by this removal.

Furthermore, here, at least the exposed electrode portions and the connecting portions of the lead wires thereto are covered with an insulating elastic outer cover after the lead wires are connected to the electrodes, so that short circuits and poor continuity occur in these portions. Never.

(Example) The present invention will be explained below based on illustrated examples.

FIG. 1 is a perspective view showing each step of the method of the present invention. In addition, the parts in the figure that are equivalent to those shown in FIG.
is an elastic skin.

The pressurized conductive rubber 1 is formed by mixing and dispersing conductive particles in rubber or a rubber-like elastic material and forming it into a sheet shape.The pressurized conductive rubber in this example has a rectangular cross-section. Note that the minimum thickness of the pressurized conductive rubber 1 can be approximately equal to the particle size of the conductive particles. Further, the electrode 2.3 is preferably made of a flexible and flexible material such as a conductive elastomer film, Todo wire, plain conductive wire, wire mesh, metal thin film, etc.
This increases the responsiveness of the switch and improves the flexibility of the switch itself, especially when turning on the switch (described later) by an external force in the direction that intersects the extending surface of the electrode, for example in the vertical direction in the illustrated example. do.

Here, these pair of electrodes 2.3 are arranged at predetermined positions across the pressurized electric rubber 1, and are covered with an insulating elastic outer skin 7 of a predetermined thickness as shown in FIG. )
A long switch structure S as shown in FIG. 3 is manufactured in advance, for example, by the method described with reference to FIG. Here, as the elastic outer cover 7, natural rubber, synthetic rubber, rubber-like elastic body, etc. can be used. Among them, silicone rubber is selected together with the base material of the pressurized conductive rubber 1 and the outer cover of the lead wire. In addition to providing excellent adhesion between them and the elastic outer cover 7, the function of the switch can be sufficiently ensured even at low temperatures of about -50°C.

Next, here, a desired part of the outer skin 4 of this switch structure S is locally cut out according to the required dimensions of the cut part using a specially manufactured stopper or other notch jig, and the electrodes 2 and 3 are cut out. Parts of the electrodes 2 and 3 are exposed as shown in FIG. 1(b), and these exposed portions of the electrodes 2 and 3 are used as lead wire connection portions 2a and 3a.

Note that here, the lead wire connection part 2 can be connected without damaging the electrode.
The resection depth of the outer skin required to form the outer skin 4 is determined by the thickness of the outer skin 4, and
, 3a are determined by the required drawing position and drawing direction of the lead wire, which will be described later.

Furthermore, as shown in FIG. 1(c), the lead wire connection portion 2
Lead wires 10 are connected to a and 3a by soldering or other appropriate means. This lead wire 1'O has an elastic jacket which is usually insulative, more preferably water-resistant, and only its tip, or in other words, the connection part, is exposed from the elastic jacket.

Here, as described above, the drawing position and drawing direction of the lead wire 10 can be changed as required by changing the forming position and dimensions of the lead wire connecting parts 2a and 3a. Part 2a, 3a
As shown in FIG. 2(a), when the lead wire 10 is provided extending in the axial direction at the end portion of the switch structure S, the lead wire 10 cannot be pulled out from the end portion of the switch structure 10 in the axial direction. I can do it.

In such a case, there is a high risk that a short circuit will occur due to the exposed connection portions of both lead wires 10 coming into contact with each other or one connection portion coming into contact with the connection portion of the other lead wire. Preferably, as shown in the figure, an insulating spacer is attached in advance to the end face of the switch assembly S between both connecting portions of the lead wires 10.degree. 10, thereby ensuring reliable prevention of short circuits.

Moreover, this connection of the lead wire 10 to the switch assembly S is as follows.
As shown in FIG. 1(c) and FIG. 2(a), this can be done before cutting the long switch assembly S to the required length, but as shown in FIG. 2(b), As shown,
This can also be carried out after cutting the long switch structure S into switch structures Sa of a predetermined length, which means that the elastic outer skin 4
The same applies to local excision.

By the way, it goes without saying that this connection of the lead wire 10 can be done manually, but the lead wire connection portion 2a,
Since 3a is located at a substantially constant position from the outer surface of the same type of switch assembly, it is also easy to connect the lead wire 10 using mechanical connection means.

Note that in this switch structure to which only the lead wire 10 is connected, the lead wire connection portions 2a, 3a and the connection portion of the lead wire 10 remain exposed, so it should not be used immediately, especially in a conductive atmosphere. Therefore, as shown in FIG. 1(d), the lead wire connection portions 2a, 3a and the connection portion of the lead wire 10 thereto are covered again with an insulating elastic outer skin, and , the pressurized conductive rubber 1 and the electrodes 2.3 exposed from at least one end surface of the switch assembly Sa cut to a required length are also covered with an insulating elastic outer cover, thereby providing sufficient durability; The present invention also constitutes a pressurized conductive switch that always operates properly.

By the way, according to this method, it is possible to extremely efficiently manufacture a pressurized conductive switch with a length of approximately 50 cm, which has a good switching function, and is free from defects such as poor insulation and poor continuity. Confirmed.

Although the present invention has been described above based on the illustrated example, the recoating after the lead wire 10 is connected is performed at the lead wire connecting portion 2a,
3a, it can be applied not only to the connection parts of the lead wires 10 and the end faces of the switch assembly Sa, but also to the entire circumference of the switch assembly Sa to which the lead wires 10 are connected, and can be manufactured as described in FIG. The outer periphery of the pressurized conductive switch can be covered again with an elastic skin having desired physical properties. In addition, as the material of the elastic outer cover, one can select from various rubber or rubber-like elastic materials with the required physical properties depending on the purpose of use of the switch, but select an elastic material with an appropriate elastic modulus. You can also adjust the sensitivity of the switch by doing this.

Furthermore, here, we have explained the case where a pressurized conductive switch is manufactured as a switch assembly Sa obtained by cutting a long switch assembly S into a required length, but when manufacturing a long pressurized conductive switch, It is not necessary to cut the long switch structure S, and in such a case, the lead wire 10
A pressurized conductive switch can be manufactured by recoating only the lead wire connection portions 2a, 3a and the connection portions of the lead wires 10 thereto after the connection.

(Effects of the Invention) Therefore, according to the present invention, by using a long switch body as a starting material, the pressurized conductive rubber and the electrode are reliably maintained in a predetermined positional relationship, so that the pressurized conductive switch There is no malfunction or conduction failure, and by locally cutting the elastic outer skin to expose the electrodes,
Insulation failure due to electrode dislocation does not occur.

Therefore, not only can a pressurized conductive switch with stable operation and high reliability be manufactured very efficiently, but also the pressurized conductive switch can be made to have sufficiently compact dimensions.

Furthermore, it becomes possible to significantly improve the material yield compared to the conventional technology.

[Brief explanation of the drawing]

Fig. 1 is a process diagram showing the method of the present invention, Fig. 2 is a perspective view illustrating another method of connecting lead wires, and Fig. 3 is a manufacturing process of a switch structure suitable for use in the method of the present invention. FIG. 3 is a cross-sectional view showing the device and switch assembly. 1... Pressurized conductive rubber 2.3... Electrode 2a,
3a...Lead wire connection part 4...Tubing machine 6...Nozzle 7...Elastic outer cover 8.9...Gap 10...Lead wire 11...Spacer S, Sa...Switch Structure diagram 2 (a) (b) Q ℃

Claims (1)

[Claims] 1. In a switch structure in which a pressurized conductive rubber and a pair of flexible electrodes placed apart from the pressurized conductive rubber are covered with an insulating elastic sheath, the elastic sheath is locally cut off, and each a step of partially exposing the electrodes, a step of connecting a lead wire to each of the exposed electrodes, and a step of covering at least the exposed electrode portions and the connecting portions of the lead wires thereto with an insulating elastic outer sheath. A method for connecting lead wires to a switch structure, which consists of sequentially combining the following steps: