JPH05342947A - Pressure-sensitive switch - Google Patents

Abstract

PURPOSE:To provide a pressure-sensitive switch which can be disposed to be bent in a large place, which is actuated by load in any direction, and of which switch sensitivity can be regulated easily. CONSTITUTION:A belt body 2 comprising insulation material is wound spirally around a center conductor 1 in such a way that the center conductor 1 is exposed partly, and a conductive rubber member 3 is provided covering the outer circumference of the belt body 2 and apart from the exposed outer circumferential surface of the center conductor 1. An insulation layer 4 is coated on the conductive rubber 3, and plural outer side conductors 5 are inserted between the conductive rubber 3 and the insulation layer 4 or into the conductive rubber 3. When the insulation layer 4 is loaded toward the center, the conductive rubber 3 is compressed to get in contact with the center conductor 1, thereby the center conductor 1 becomes continuous with the outer side conductor 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-sensitive switch which conducts (on) when it is weighted and turns off when the pressure of the weight is released.

[0002]

2. Description of the Related Art As a conventional pressure-sensitive switch, a pair of flexible electrodes are arranged on both sides of a conductive rubber in which metal particles, carbon black and other conductive particles are mixed and dispersed in a rubber, and these are made elastic. A flat shape covered with an outer cover is known. Lead wires are connected to the electrodes. When the outer skin is pressed toward the conductive rubber at the center and the pair of electrodes are pressed against the conductive rubber together, the conductive rubber elastically compresses and deforms, and the electrical resistance compression value is significantly reduced in the compressed part, and both electrodes are electrically connected to each other. Switch is turned on.

[0003]

The conventional pressure-sensitive switch is partially suitable for use as, for example, one provided inside the seat to detect the seating state (Japanese Patent Laid-Open No. 1-160747). However, in a wide place, for example, when a wire rod wire is used instead of an intruder to detect intruders or other cord-shaped long objects are needed, there is a disadvantage that the switch is turned on when the product is bent and installed. It was Also,
In the conventional pressure-sensitive switch, the switch does not turn on depending on the weighting direction, and it is also difficult to adjust the switch sensitivity.

Therefore, the present invention provides a pressure-sensitive switch which can be bent in a wide area and arranged in an unusual arrangement so that the switch operates even if a load is applied from any direction and the switch sensitivity is easily adjusted. The purpose is to

[0005]

In order to achieve the above-mentioned object, the present invention relates to a strip-shaped body formed by spirally winding a strip-shaped body made of an insulating material around the outer periphery of the central conductor so that the central conductor is partially exposed. The conductive rubber is provided so as to cover the outer periphery of the core conductor and away from the exposed outer peripheral surface of the central conductor, and the conductive rubber is covered with an insulating layer, and a plurality of outer conductors are inserted between the conductive rubber and the insulating layer or in the conductive rubber, When the insulating layer is weighted toward the center, the conductive rubber is compressed and comes into contact with the central conductor so that the central conductor and the outer conductor are electrically connected.

[0006]

According to the present invention, the belt-like body functions as a spacer, and maintains a gap between the conductive rubber and the center conductor to keep the center conductor and the outer conductor from being non-conducting even when the belt is not straightened and is bent without being loaded. When the pressing force is applied from any direction of the outer insulating layer while maintaining the state, the conductive rubber is compressed and comes into pressure contact with the central conductor, and the central conductor and the outer conductor are electrically connected to each other to turn on the switch. When the applied pressure is released, the elasticity of the conductive rubber itself restores it. The switch sensitivity is adjusted by adjusting the winding pitch of the spiral of the strip, and if this pitch is long, the exposed area of the central conductor becomes large and the switch sensitivity becomes sensitive. Conversely, if the pitch is short, the switch sensitivity becomes Get dull.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. In the embodiment shown in FIG. 1, the central conductor 1
A strip 2 made of an insulating material is spirally wound around the outer periphery of the core so that the central conductor 1 is partially exposed. As the central conductor 1, a twisted wire obtained by plating a copper electric wire with tin was used, and as the strip 2, nylon 6 was used. A conductive rubber 3 is provided so as to cover the outer periphery of the band-shaped body 2 and apart from the exposed outer peripheral surface of the central conductor 1, and the insulating layer 4 is provided on the outer periphery of the conductive rubber 3.
And a plurality of outer conductors 5 are inserted between the conductive rubber 3 and the insulating layer 4. The conductive rubber 3 is formed by vulcanizing and mixing metal particles, carbon black or other conductive particles in rubber. The insulating layer 4 is coated with silicon or silicon rubber. As the outer conductor 5, a flat braided wire, which is a copper wire plated with tin, is used as in the case of the center conductor 1. In the illustrated embodiment, the outer diameter a of the central conductor 1 is 2.5 mm, the outer diameter b of the strip 2 is 3.6 mm, the outer diameter c of the conductive rubber 3 is 5.6 mm, and the outer diameter d of the insulating layer 4 is It was set to 7.2 mm. Further, the pitch p of the strip-shaped body 2 spirally wound around the central conductor 1 was set to 5.0 mm. Further, the width t of the strip 2 was set to 2.0 mm. The interval of the pitch p and the width t of the strip 2 is adjusted according to the sensitivity required for the switch.

As shown in FIG. 2, four outer conductors 5 are arranged between the conductive rubber 3 and the insulating layer 4 at four equal positions on the peripheral surface thereof. The spiral strip 2 functions as a spacer and prevents the central conductor 1 from coming into contact with the conductive rubber 3 when not loaded. If the interval of p + t is long, the sensitivity as a switch becomes sensitive, and if this interval is narrow, the sensitivity as a switch becomes dull. Various materials can be used for the strip 2 as long as it has predetermined rigidity and flexibility.

FIG. 3 shows a state in which a load is applied from the direction of the arrow. At this time, the conductive rubber 3 is compressed and comes into contact with the central conductor 1, and the central conductor 1 and the outer conductor 5 are electrically connected to each other to turn on the switch. Becomes When the applied pressure is released, the elasticity of the conductive rubber 3 itself and the existence of the belt-shaped body 2 restores the original state and the switch is turned off.

Another embodiment shown in FIG. 4 shows the outer conductor 5 using a twisted wire of a copper wire plated with tin.
It is arranged in the conductive rubber 3.

The plurality of outer conductors 5 are twisted together at one end side to form a lead wire, and the center conductor 1 itself also forms a lead wire, which are connected to positive and negative power supplies (not shown), respectively. Thus, if the central conductor 1 and the outer conductor 5 are electrically connected to each other through the conductive rubber 3, a current flows and the switch is turned on.

[0012]

As described above, according to the present invention, a strip made of an insulating material is spirally wound around the outer periphery of the central conductor so that the central conductor is partially exposed, and the outer periphery of the strip is covered. In addition, the conductive rubber is provided away from the exposed outer peripheral surface of the central conductor, the conductive rubber is covered with the insulating layer, and a plurality of outer conductors are inserted between or between the conductive rubber and the conductive rubber. When the load is applied to the conductive rubber, the conductive rubber is compressed and comes into contact with the central conductor so that the central conductor and the outer conductor are electrically connected, so that the switch is turned on when the insulating layer is loaded from any direction, It can be used in a variety of applications as compared to only from a particular direction.
Also, when used as a cord-shaped long object, even if this pressure-sensitive switch is bent and arranged, the conductive rubber and the central conductor do not come into contact with each other, and the spiral band freely bends. Therefore, it can be installed in a place having a complicated shape. Further, the sensitivity of the switch can be easily adjusted by the winding pitch of the strip.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view showing a preferred embodiment of the present invention.

FIG. 2 is a sectional view.

FIG. 3 is a cross-sectional view showing a conductive state when a load is applied.

FIG. 4 is a cross-sectional view showing another embodiment.

[Explanation of symbols]

 1 central conductor 2 strip 3 conductive rubber 4 insulating layer 5 outer conductor

Claims (1)

[Claims] 1. A band-shaped body made of an insulating material is spirally wound around the outer periphery of the central conductor so that the central conductor is partially exposed, and the outer periphery of the band-shaped body is covered with a conductive material away from the outer peripheral surface where the central conductor is exposed. Provide a rubber, cover the insulating layer with the conductive rubber, and insert multiple outer conductors between the conductive rubber and the insulating layer or into the conductive rubber so that the conductive rubber is compressed when the insulating layer is weighted toward the center. A pressure-sensitive switch, which is in contact with a central conductor and electrically connects the central conductor and an outer conductor.