JP6947053B2 - Code switch - Google Patents

Description

The present invention relates to a cord switch.

Conventionally, a cord switch has been used to prevent a foreign object (for example, a human body) from being caught in a sliding door or the like of a vehicle (see, for example, Patent Document 1). To prevent foreign matter (eg, the human body) from being caught in the sliding door of the vehicle, the cord switch is installed along the door edge of the sliding door.

The cord switch described in Patent Document 1 has a tubular member having elasticity and insulation properties and a hollow portion formed along the longitudinal direction, and a tubular member having a conductor formed by twisting a plurality of metal strands. It is provided with a plurality of electrode wires provided on the inner surface of the above surface at intervals from each other. In this cord switch, when pressure is applied to a tubular member due to contact with, for example, a human body, at least two of a plurality of electrode wires separated from each other come into contact with each other. Therefore, by detecting the contact of the electrode wires, it is possible to detect the contact of the human body or the like.

International Publication No. 2015/194030

By the way, it is conceivable that the cord switch is installed along the edge of a door such as a sliding door in a more complicated layout. At that time, the cord switch may be installed along a curved portion having a smaller bending radius.

However, when the cord switch is installed along the curved portion having a small bending radius in this way, there is a problem that the tubular member buckles. In this case, even though the foreign matter (for example, the human body) is not in contact with the cord switch, there is a possibility that the electrode wire may come into contact with the cord switch in advance due to buckling of the tubular member.

Therefore, an object of the present invention is to provide a cord switch capable of suppressing buckling of a tubular member.

An object of the present invention is to solve the above-mentioned problems, a plurality of electrode wires arranged opposite to a hollow tubular member having elasticity and insulation property inside the tubular member and separated by the elastic force of the tubular member. Each of the plurality of electrode wires has a conductor obtained by twisting a plurality of metal strands, and all the metal strands constituting the conductor are spirally twisted to form a cord switch. offer.

According to the present invention, it is possible to provide a cord switch capable of suppressing buckling of a tubular member.

It is a figure which shows the cord switch which concerns on one Embodiment of this invention, (a) is a sectional view perpendicular to the longitudinal direction, (b) is a perspective view. (A) is a cross-sectional view of the electrode wire, and (b) is an enlarged view of part A of (a). It is explanatory drawing explaining the manufacturing method of a conductor. It is a perspective view of the cord switch which concerns on one modification of this invention.

[Embodiment]
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

(Overall configuration of code switch)
1A and 1B are views showing a code switch according to the present embodiment, FIG. 1A is a cross-sectional view perpendicular to the longitudinal direction, and FIG. 1B is a perspective view.

FIG. 1 (a). As shown in (b), the cord switch 1 has an elastic and insulating hollow tubular member 2 and a plurality of electrode wires arranged to face each other inside the tubular member 2 and separated by the elastic force of the tubular member 2. 3 and.

The tubular member 2 is formed in a cylindrical shape (cylindrical shape in a state where no pressing force is applied from the outside) having a hollow portion 2a along the longitudinal direction. It is desirable that the tubular member 2 is made of a material having low compression set and excellent flexibility, cold resistance, water resistance, chemical resistance, weather resistance and the like. Specifically, as the tubular member 2, for example, a rubber-based composition obtained by cross-linking an ethylene-propylene-diene copolymer, an olefin-based or styrene-based thermoplastic elastomer composition that does not require a cross-linking step, or the like is preferable. Can be used for. The outer diameter of the tubular member 2 is, for example, 4 mm.

The plurality of electrode wires 3 each have a conductor 31 in which a plurality of metal strands 31a are twisted together, and a conductive coating layer 32 that covers the outer periphery of the conductor 31. 1 (a) and 1 (b) show a case where four electrode wires 3 are arranged at equal intervals in the circumferential direction on the inner surface of the tubular member 2, but the number of electrode wires 3 is limited to this. It is not something that is done, and it is sufficient if there are two or more.

In the present embodiment, the plurality of electrode wires 3 are spirally arranged inside the tubular member 2. As a result, the electrode wires 3 can easily come into contact with each other regardless of the direction in which the cord switch 1 is pressed, and it is possible to suppress the detection omission of foreign matter contact.

The metal wire 31a used for the conductor 31 is made of copper or a copper alloy. The surface of the metal wire 31a may be plated with tin, nickel, silver, zinc or the like for the purpose of increasing heat resistance. The outer diameter of the metal wire 31a is, for example, 0.1 mm. Details of the conductor 31 will be described later.

As the conductive coating layer 32, one having elasticity and insulating property is used. Further, as the conductive coating layer 32, similarly to the tubular member 2, the compression set is small, excellent in flexibility, cold resistance, water resistance, chemical resistance, weather resistance, etc., and has high conductivity and elastic insulation. Those with high adhesion to the body are used. As the conductive coating layer 32, it is more preferable to use a resin used for the tubular member 2 mixed with a conductive filler such as carbon black. That is, it is desirable that the conductive coating layer 32 and the tubular member 2 are made of the same material as the main component. Specifically, the conductive coating layer 32 includes, for example, a rubber-based composition obtained by cross-linking ethylene-propylene-diene copolymer, an olefin-based or styrene-based thermoplastic elastomer composition that does not require a cross-linking step, carbon black, or the like. It is preferable to use the one containing the conductive filler of.

In the cord switch 1, when a pressing force is applied from the outside, the tubular member 2 is elastically deformed, the hollow portion 2a is crushed, and the electrode wires 3 come into contact with each other. Therefore, by detecting the contact (short circuit) of the electrode wire 3, it is possible to detect that a foreign substance such as a human body has come into contact with the cord switch 1.

(Details of conductor 31)
FIG. 2A is a cross-sectional view of the electrode wire 3, and FIG. 2B is an enlarged view of part A thereof. In the cord switch 1 according to the present embodiment, all the metal strands 31a constituting the conductor 31 are spirally twisted together. In other words, in the present embodiment, the untwisted metal wire 31a is not included in the conductor 31. The reason for this will be described below.

A twisting method called concentric twisting is known in which a plurality of (for example, six) metal strands 31a are spirally twisted around one metal strand 31a. In this concentric twist, no twist is applied to the metal wire 31a arranged at the center, so that the conductor 31 is difficult to extend in the longitudinal direction. Therefore, when the conductor 31 is concentrically twisted, when the cord switch 1 is bent with a small bending radius, the conductor 31 cannot follow the elongation of other members and receives the stress of the conductor 31 which is difficult to stretch, and the tubular member 2 Bends and becomes easy to buckle.

On the other hand, when all the metal strands 31a constituting the conductor 31 are spirally twisted as in the present embodiment, the conductor 31 is easily extended in the longitudinal direction, and the tubular member 2 is also seated. It becomes difficult to give in. Further, since the conductor 31 acts as a reinforcing material for the tubular member 2 and makes the cord switch 1 less likely to be crushed, buckling is less likely to occur as compared with the case where the conductor 31 is not provided.

The conductor 31 may be a stranded conductor formed by so-called collective twisting in which metal strands 31a are bundled and all of them are twisted together. In the present embodiment, a plurality of metal strands 31a constituting the conductor 31 are arranged and arranged in the circumferential direction of the conductor 31 so that the conductor 31 can be easily extended in the longitudinal direction. In the cross section perpendicular to the longitudinal direction of the conductor 31, the metal strands 31a are arranged in a circular shape, and the hollow conductor portion 31b is formed in the central portion thereof. The hollow conductor portion 31b surrounded by the metal wire 31a is located at the center of the conductor 31 in a cross section perpendicular to the longitudinal direction of the conductor 31, and is formed along the longitudinal direction of the conductor 31. That is, the conductor 31 is formed in a hollow cylindrical shape as a whole. Further, it can be said that the plurality (6) metal strands 31a are spirally twisted around the outer periphery of the hollow conductor portion 31b. Since the conductor 31 has the hollow conductor portion 31b, even when the cord switch 1 is pressed with a strong force and the electrode wires 3 come into contact with each other with a strong force, the hollow conductor portion 31b serves as a cushion to form the electrode wire 3. It becomes possible to suppress damage.

In the present embodiment, the number of metal strands 31a constituting the conductor 31 is set to 6. That is, in the present embodiment, in the concentric twist using the seven metal wire 31a, the metal wire 31a arranged at the center is omitted. As the number of metal strands 31a is reduced, the diameter of the spiral when twisting the metal strands 31a becomes smaller, and the conductor 31 becomes difficult to extend in the longitudinal direction. Therefore, the number of metal strands 31a constituting the conductor 31 is increased. , It is desirable to have 6 or more.

Further, if the twist pitch of the metal wire 31a in the conductor 31 is too long, it becomes difficult for the conductor 31 to extend in the longitudinal direction. The twist pitch of the metal wire 31a in the conductor 31 is preferably at least smaller than the twist pitch (spiral pitch) of the electrode wire 3. The twist pitch of the conductor 31 is the distance along the longitudinal direction of the conductor 31 from a certain position in the circumferential direction until the arbitrary conductor 31 makes one rotation in the circumferential direction of the conductor 31 and returns to that position. Further, the twist pitch of the electrode wire 3 is the distance along the longitudinal direction of the cord switch 1 from a certain position in the circumferential direction of the electrode wire 3 to one rotation in the circumferential direction of the cord switch 1 and returning to that position. Is. The twist pitch of the electrode wire 3 is larger than the twist pitch of the metal wire 31a, for example, 10.0 mm. The twist pitch of the metal wire 31a is, for example, 3.0 mm.

Further, it is desirable that the winding direction of the spiral of the plurality of electrode wires 3 and the twisting direction of the metal wire 31a in the conductor 31 are opposite directions. This is because if the winding direction of the spiral of the electrode wire 3 and the twisting direction of the metal wire 31a in the conductor 31 are the same direction, the cord switch 1 is likely to swell (twist) due to the force of untwisting. Because. That is, by making the winding direction of the spiral of the electrode wire 3 and the twisting direction of the metal wire 31a in the conductor 31 opposite to each other, it becomes easy to obtain a linear cord switch 1 with less waviness (twist).

When manufacturing the conductor 31, a stranded wire manufacturing apparatus 40 as shown in FIG. 3 is used to extend each of the six metal wire 31a from the bobbin 41 for wire, pass it through a die 42, and pass the die 42. The passing conductor 31 is wound around the drum 43. By winding the drum 43 while rotating it, the metal strands 31a can be twisted together.

The six metal strands 31a are aligned and arranged in a circular shape (cylindrical shape) in the die 42. The inside of the die 42 is gradually reduced in diameter from the entrance side to the exit side, and the diameter of the outlet of the die 42 is slightly smaller than the outer diameter when the six metal strands 31a are arranged in a circular shape. It is the diameter. As a result, as shown in FIG. 2B, each metal wire 31a is pushed inward in the radial direction and becomes slightly crushed, the metal wire 31a becomes difficult to unravel, and the conductor 31 is held in a cylindrical shape. NS. That is, in the present embodiment, the metal strands 31a are slightly deformed from the circular shape before being twisted, and the metal strands 31a adjacent to each other in the circumferential direction of the conductor 31 are pressed against each other and are in contact with each other on the surface. It has become.

In the present embodiment, since the electrode wires 3 are arranged in a spiral shape, when the cord switch 1 is bent, the twist pitch of the electrode wires 3 becomes narrower inside the bend as when the spring is bent. The electrode wire 3 is deformed so that the twist pitch of the electrode wire 3 becomes wider on the outside of the bending. Therefore, in the cord switch 1 in which the electrode wires 3 are arranged in a spiral shape, the bending may be sufficiently followed even if the elongation of the conductor 31 is small. However, such a property appears when the twist pitch of the electrode wire 3 is sufficiently short, and when the twist pitch of the electrode wire 3 is long, if the elongation of the conductor 31 is small, buckling tends to occur.

Further, if the twist pitch of the electrode wire 3 is shortened, the electrode wire 3 included in the unit length of the cord switch 1 becomes long, and the cost also increases. Therefore, it is desired to reduce the cost by making the twist pitch of the electrode wire 3 as long as possible. As in the present embodiment, by setting all the metal strands 31a constituting the conductor 31 in a spirally twisted state, the twist pitch of the electrode wire 3 is lengthened for cost reduction. However, it is possible to realize a cord switch 1 that does not easily buckle.

(Modification example)
In the present embodiment, the case where the electrode wire 3 is spirally arranged inside the tubular member 2 has been described, but the electrode wire 3 is inside the tubular member 2 as in the code switch 1a shown in FIG. It may be arranged linearly along the longitudinal direction. The cord switch 1a has an advantage that it is easy to manufacture and low in cost as compared with the above-mentioned cord switch 1 in which the electrode wires 3 are arranged in a spiral shape. However, in this cord switch 1a, in order to suppress buckling when bending is applied, the electrode wire 3 arranged outside the bending needs to be sufficiently stretched in the longitudinal direction. Therefore, by applying the present invention and setting all the metal strands 31a constituting the conductor 31 in a spirally twisted state, the electrode wire 3 can be sufficiently stretched in the longitudinal direction, and the seat of the tubular member 2 can be sufficiently stretched. It becomes possible to suppress bending.

(Actions and effects of embodiments)
As described above, in the cord switch 1 according to the present embodiment, all the metal strands 31a constituting the conductor 31 of the electrode wire 3 are spirally twisted together. As a result, the conductor 31 is easily stretched in the longitudinal direction, so that it is possible to prevent the tubular member 2 from buckling even when the cord switch 1 is bent with a small bending radius, and the allowable bendability is excellent. The code switch 1 can be realized. As a result, it is possible to realize a code switch 1 that can handle a more complicated layout.

(Summary of embodiments)
Next, the technical idea grasped from the above-described embodiment will be described with reference to the reference numerals and the like in the embodiment. However, the respective reference numerals and the like in the following description are not limited to the members and the like in which the components in the claims are specifically shown in the embodiment.

[1] A hollow tubular member (2) having elasticity and insulating properties, and a plurality of electrode wires (3) arranged to face each other inside the tubular member (2) and separated by the elastic force of the tubular member (2). ), And the plurality of electrode wires (3) each have a conductor (31) obtained by twisting a plurality of metal strands (31a), and all the metal strands constituting the conductor (31). A cord switch (1) in which (31a) is twisted in a spiral shape.

[2] The plurality of metal strands (31a) constituting the conductor (31) are arranged so as to be aligned in the circumferential direction of the conductor (31), and are surrounded by the metal strands (31a). The code switch (1) according to [1], wherein a hollow conductor portion (31b) is formed along the longitudinal direction of the conductor (31).

[3] The code switch according to [2], wherein the number of the metal strands (31a) constituting one conductor (31) is 6 or more.

[4] The plurality of electrode wires (3) are spirally arranged inside the tubular member (2), and the spiral winding direction of the plurality of electrode wires (3) and the conductor (31). The cord switch (1) according to any one of [1] to [3], wherein the twisting direction of the metal wire (31a) is opposite to that of the metal wire (31a).

[5] The code switch (1) according to any one of [1] to [4], wherein the outer periphery of the conductor (31) is covered with a conductive coating layer (32).

[6] The cord switch according to [5], wherein the conductive coating layer (32) is made of a rubber composition or a thermoplastic elastomer composition containing a conductive filler.

Although the embodiments of the present invention have been described above, the embodiments described above do not limit the invention according to the claims. It should also be noted that not all combinations of features described in the embodiments are essential to the means for solving the problems of the invention. In addition, the present invention can be appropriately modified and implemented without departing from the spirit of the present invention.

1 ... Cord switch 2 ... Tubular member 2a ... Hollow portion 3 ... Electrode wire 31 ... Conductor 31a ... Metal wire 31b ... Conductor hollow portion 32 ... Conductive coating layer

Claims (7)

Hollow tubular members with elasticity and insulation,
A plurality of electrode wires arranged to face each other inside the tubular member and separated by the elastic force of the tubular member.
The plurality of electrode wires each have a conductor obtained by twisting a plurality of metal strands.
All the metal wires constituting the conductor are spirally twisted and arranged so as to be aligned in the circumferential direction of the conductor, and the hollow portion of the conductor surrounded by the metal wires and along the longitudinal direction of the conductor is formed. Formed,
Code switch. Hollow tubular members with elasticity and insulation,
A plurality of electrode wires arranged to face each other inside the tubular member and separated by the elastic force of the tubular member.
The plurality of electrode wires each have a conductor obtained by twisting a plurality of metal strands.
All the metal strands that make up the conductor are spirally twisted together .
The plurality of electrode wires are spirally arranged inside the tubular member.
The winding direction of the spiral of the plurality of electrode wires and the twisting direction of the metal wire in the conductor are opposite directions.
Code switch. The plurality of metal strands constituting the conductor are arranged so as to be aligned in the circumferential direction of the conductor, and a hollow conductor portion is formed so as to be surrounded by the metal strands and along the longitudinal direction of the conductor.
The code switch according to claim 2. The number of the metal strands constituting one conductor is 6 or more.
The code switch according to claim 1 or 3. The plurality of electrode wires are spirally arranged inside the tubular member.
The winding direction of the spiral of the plurality of electrode wires and the twisting direction of the metal wire in the conductor are opposite directions.
The code switch according to claim 1. The outer circumference of the conductor is covered with a conductive coating layer.
The code switch according to any one of claims 1 to 5. The conductive coating layer comprises a rubber composition or a thermoplastic elastomer composition containing a conductive filler.
The code switch according to claim 6.

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