JP2001174348A - Pressure sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure sensor capable of detecting pressure at high sensitivity with a relatively simple structure. SOLUTION: This pressure sensor 10 is provided with an elastic conductive tube 21 and a slender composite member 24 having a first electrode member 22 and a second electrode member 23 provided separately from each other along the longitudinal direction. Both electrode members 22, 23 have flexible and slender metal conductors 22a, 23a and elastic conductive members 22b, 23b provided along the longitudinal direction of the metal conductors 22a, 23a to cover at least the partial segments in the peripheral direction of the outer peripheries of the metal conductors 22a, 23a. The electrode members 22, 23 are arranged separately from the elastic conductive tube 21 in the natural state of the elastic conductive tube 21, and they can be electrically connected together via the elastic conductive tube 21 when the elastic conductive tube 21 is elastically deformed by the pressing force from the outside.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure sensor for detecting a pressure (including a load).

[0002]

2. Description of the Related Art A conventional general pressure sensor has a structure in which a pressure-sensitive conductive member formed by mixing a conductive material into an elastic material such as rubber is sandwiched between positive and negative electrode plates. In this pressure sensor, pressure application is detected by detecting a decrease in the resistance value of the pressure-sensitive conductive member caused by the pressure-sensitive conductive member being elastically deformed so as to be crushed by the pressing force.

[0003]

However, in the above-described pressure sensor, it is sometimes difficult to detect the pressure sensitively because the sensitivity of the pressure-sensitive conductive member is low.

An object of the present invention is to provide a pressure sensor capable of detecting pressure with high sensitivity with a relatively simple configuration.

[0005]

The technical means for achieving the above object is to provide a tubular elastic conductive tube in which at least a part of the circumferential direction is a conductive portion having conductivity, a tubular elastic conductive tube which is separated from each other. And an elongated composite member provided in the elastic conductive tube, the first electrode member and the second electrode having a first electrode member and a second electrode member provided along the longitudinal direction. The member includes a flexible elongated metal conductor and an elastic conductive member provided along a longitudinal direction of the metal conductor so as to cover at least a part of a circumferential portion of an outer peripheral portion of the metal conductor. The elastic conductive tube is disposed apart from the conductive portion of the elastic conductive tube in the natural state of the elastic conductive tube, while the elastic conductive tube is elastically deformed by an external pressing force. Via the conductive portion of the conductive tube, characterized in that it is arranged to be capable of electrically connecting to each other.

The technical means for achieving the above object is to provide an elongated metal conductor having flexibility and the metal conductor so as to cover at least a part of a circumferential portion of an outer peripheral portion of the metal conductor. A first electrode member and a second electrode member each provided with an elastic conductive member provided along the longitudinal direction of the first electrode member and the second electrode member while holding the first electrode member and the second electrode member in a separated state, An elastic holding member that elastically deforms when a pressing force is applied in a direction to bring the electrode member and the second electrode member close to each other and allows the first electrode member and the second electrode member to come into contact with each other, It is characterized by having.

Further, preferably, the metal conductor is a stranded wire formed by twisting a plurality of metal wires, or a flexible core material and a metal wire spirally wound around the outer periphery of the core material. And a winding having

Further, the technical means for achieving the above object is to provide a tubular elastic conductive tube in which at least a part of the circumferential direction is a conductive portion having conductivity, and a tubular elastic conductive tube which is spaced apart from each other in the longitudinal direction. An elongated composite member provided in the elastic conductive tube, the first electrode member and the second electrode member having an elongated shape. A metal conductor having a shape, and an elastic conductive member provided along a longitudinal direction of the metal conductor so as to cover at least a part of a circumference of an outer peripheral portion of the metal conductor, and a natural state of the elastic conductive tube. When the elastic conductive tube is disposed apart from the conductive portion of the elastic conductive tube, when the elastic conductive tube is elastically deformed by an external pressing force, the elastic conductive tube is electrically conductive. The metal conductor of at least one of the first electrode member and the second electrode member has a predetermined resistance per unit length. It is a metal resistance conductor having a value.

[0009] Further, the technical means for achieving the above-mentioned object is to extend the metal conductor along the longitudinal direction of the metal conductor so as to cover at least a part of the peripheral portion of the elongated metal conductor in the circumferential direction. A first electrode member and a second electrode member, each of which has an elastic conductive member provided with the first electrode member and the second electrode member, while holding the first electrode member and the second electrode member in a separated state. An elastic holding member that allows the first electrode member and the second electrode member to come into contact with each other when a pressing force is applied in a direction in which the two electrode members are brought close to each other, and the first electrode member and the The metal conductor of at least one of the second electrode members is a metal resistance conductor having a predetermined resistance value per unit length.

Preferably, the metal resistance conductor is
It is preferable to use a metal resistance wire or a resistance winding provided with a flexible core material and a metal resistance wire spirally wound around the outer periphery of the core material.

[0011]

<First Embodiment> FIG. 1 is a cutaway perspective view of a pressure sensor 10 according to a first embodiment of the present invention. As shown in FIG. 1, the pressure sensor 10 includes a hollow tube-shaped elastic conductive tube 21 and first and second positive and negative electrode members 22 and 23 which are loosely inserted into the elastic conductive tube 21. An elongated composite member 24 having elasticity.

As shown in FIG. 1, the elastic conductive tube 21 is a substantially cylindrical tube having a hollow portion 28, and is entirely formed of a conductive elastic material such as conductive rubber. Here, the whole is a conductive portion.

As shown in FIG. 1, the composite member 24 has side end insulators 31 and 32 formed at both end portions in cross section, a central insulator portion 33 arranged in the center portion in cross section, and one side. The first electrode member 22 formed between the end insulator portion 31 and the central insulator portion 33, and the second electrode formed between the other side end insulator portion 32 and the central insulator portion 33 on the other side And a member 23.

Each of the electrode members 22 and 23 is formed of an elongated metal conductor 22a or 23a having flexibility and the metal conductor 2a or 23a.
Elastic conductive members 22b, 23b provided along the longitudinal direction of the metal conductors 22a, 23a so as to cover at least a part of the outer peripheral portion of the outer periphery of the 2a, 23a (here, the upper and lower sections). ing.

The elastic conductive members 22b and 23b are formed integrally with each of the insulator portions 31 to 33 by extrusion molding using a conductive elastic material such as conductive rubber similar to the elastic conductive tube 21. In order to secure sufficient flexibility, the metal conductors 22a and 23a may be formed by twisting a plurality of metal wires or, as shown in FIG. The core member 100 is configured by a winding having a spirally wound metal wire 101 on the outer periphery thereof. Here, the core material 100 of the winding in FIG. 2 is formed by, for example, extruding and covering a rubber material on an outer periphery of a string-shaped tensile strength wire. The wire diameter of the winding in FIG.
8 mm, and the metal wire 101 has a wire diameter of 50 μm, for example.
Copper wire or nichrome wire.

The electrode members 22 and 23 having such a configuration are
The elastic conductive members 22b, 23 are provided on the metal conductors 22a, 23a.
b by extrusion coating with each of the insulator portions 31 to 33, or by forming the elastic conductive member 22b,
An internal cavity is provided in the longitudinal direction at a predetermined portion in 23b and the insulator portions 31 to 33, and the metal conductors 22 and 33 are inserted into the internal cavity.

With such a configuration, when pressure is applied from above in FIG. 1 (the direction of arrow Dr1 in FIG. 3), which is the thickness direction of the composite member 24, the elastic conductive tube 21 and the composite member 24 are separated from each other in FIG. The first electrode member 22 and the elastic conductive tube 21 come into contact with each other, and the second electrode member 23 and the elastic conductive tube 21 come into contact with each other. Is electrically conducted through the elastic conductive tube 21. Of course, when the shape of the elastic conductive tube 21 returns to the natural tubular state, the shape of the composite member 24 is elastically restored to its original state.

The composite member 24 is made of the elastic conductive tube 2.
For example, as shown in FIG. 4, the composite member 24 can be rotated within the hollow portion 28 of the elastic conductive tube 21.
When the pressing force is applied from above the elastic conductive tube 21 (in the direction of arrow Dr2 in FIG. 4) when the oblique posture is taken from the upper left to the lower right in FIG. R1 (counterclockwise) easily turns into the state of FIG.
3 are electrically conducted through the elastic conductive tube 21.

Thus, a signal line (not shown) for extracting a signal is connected to, for example, an end of each of the two electrode members 22 and 23, and the first electrode member 22 is connected via the signal line.
By detecting the presence or absence of electrical continuity between the second electrode member 23 and the second electrode member 23, the presence or absence of pressure application can be detected.

As described above, according to the present embodiment, since the elastic conductive tube 21 has a hollow shape, it can be elastically deformed relatively easily. Since the pressure is detected by detecting the presence or absence of the conduction between the first electrode member 22 and the second electrode member 23, the pressure sensor can detect the pressure with high sensitivity with a relatively simple configuration. 10 can be provided.

By the way, conductive rubber or the like is generally used as the elastic conductive members 22b and 23b.
Since the resistance value changes due to deformation (elongation) due to external pressure,
When the first electrode member 22 and the second electrode member 23 are constituted only by the elastic conductive members 22b and 23b, the two electrode members 22,
23 may become unstable and the electrical characteristics of the pressure sensor 10 may become unstable.

On the other hand, in the present embodiment, the first electrode member 22 and the second electrode member 23 are formed of flexible elongated metal conductors 22a, 23a and the metal conductors 22a, 23a.
Since it is provided with elastic conductive members 22b, 23b provided along the longitudinal direction of the metal conductors 23a, 23a so as to cover at least a part of the circumferential direction of the metal conductor 23a, both metal conductors 22a, 23a Electrode member 22,
The resistance value of the pressure sensor 23 is stabilized, and the second effect that the electrical characteristics of the pressure sensor 10 can be stabilized is obtained.

Since the first electrode member 22 and the second electrode member 23 use flexible metal conductors 22a, 23a, the first electrode member 22 and the second electrode member are formed by the metal conductors 22a, 23a. 23 and the flexibility of the pressure sensor 10 are not impaired,
0 can be sufficiently secured, and as a result, the pressure sensor 10 can be flexibly deformed and adapted to the application of the pressing force. The third effect that the degree can be increased can be obtained.

The metal conductors 2 are provided on both electrode members 22 and 23.
2a, 23a, the metal conductors 22a,
A fourth effect is obtained in that the connection between the two electrode members 23, 23 and the signal lines for signal extraction can be easily and firmly made by a simple connection method such as solder connection or crimp connection using the 23a. Can be

Further, since the metal conductors 22a and 23a provided on the first electrode member 22 and the second electrode member 23 are formed of stranded wires or windings of FIG. 2, the flexibility of the pressure sensor 10 is increased. It can be further improved.

<Second Embodiment> In the pressure sensor 10 according to the second embodiment of the present invention, in the pressure sensor 10 according to the first embodiment, the metal conductors 22a and 23a of the electrode members 22 and 23 are different from each other. It is composed of metal resistance conductors 22a and 23a having a predetermined resistance value per unit length, and the other configuration is the same as that of the first embodiment.

The metal resistance conductors 22a and 22a according to the present embodiment
More specifically, 3a is constituted by a metal resistance wire such as a nichrome wire or a metal wire such as a nichrome wire instead of the metal wire 101 in the winding shown in FIG. Here, the resistance value per unit length of the metal resistance conductors 22a and 23a is set to, for example, 1 Ω / m to 40 kΩ / m. When the metal resistance conductors 22a and 23a are formed by windings, there is an advantage that the flexibility of the electrode members 22, 23 and the pressure sensor 10 can be improved.

FIG. 5 is an equivalent circuit diagram showing an example of a connection relationship between the pressure sensor 10 and a detection circuit section 41 connected to the pressure sensor 10 when no pressure is applied.
Here, one end of the first electrode member 22 of the pressure sensor 10 is connected to the connection terminal 38, the lead wire 37a, and the pull-down resistor R.
_O is connected to the positive electrode side of the power supply E, and one end of the second electrode member 23 is connected to the negative electrode side of the power supply E through the connection terminal 39 and the lead wire 37b. The other ends of the electrode members 22 and 23 are connected to each other via a terminating resistor 42. Then, in the detection circuit section 41, the partial voltage applied to the pull-down resistor R _O (V1 in FIG. 5, V1 in FIG. 7)
2) is detected. Here, the partial voltage applied to the pull-down resistor R _O is detected, but an intermediate voltage between the pull-down resistor R _O and the connection terminal 39 may be detected.

Here, when no pressure is applied as shown in FIG. 1 and the like, the first electrode members 22 and 23 of the composite member 24 are
Are separated from the elastic conductive tube 21. Therefore, in this case, the two electrode members 22 and 23 and the detection circuit 4
1 and the terminating resistor 42 are as shown in FIG. Here, the length of each of the electrode members 22 and 23 as conductive paths in the pressure sensor 10 is L, and the electrical resistance per unit length of the conductive paths (electrode members 22 and 23) is r.
_D , assuming that the resistance value of the terminating resistor 42 is _RL , the input resistance R1 as viewed from the detection circuit unit 41 constituted by the two electrode members 22, 23 and the terminating resistor 42 is R1 = 2r _D L + R _L (1) Therefore, the detection voltage level V1 in the detection circuit unit 41 is represented by the following expression (2).

[0030] _{V1 = R O E / (2r} D L + R L + R O) ... (2) In the present embodiment, the metal resistance conductor 22a having a predetermined resistance value per unit length in the both electrode members 22 and 23 ,
Since 23a is used, the resistance value per unit length of both electrode members 22, 23 can be made uniform.

[0031] Here, assumed to be set to _{R L> r D L ... (} 3) R O <R L ... (4).

On the other hand, as shown in FIG.
When the pressure is applied at the position of the point X, the elastic conductive tube 21 bends and contacts the first electrode member 22 and the second electrode member 23 at the point X as shown in FIG. In this case, assuming that the resistance value of the elastic conductive tube 21 is R _D and the distance from the connection side end of the lead wire 37 of the pressure sensor 10 in FIG. 6 to the point X is x, both electrode members 22, 23,
Circuit constituted by the detection circuit section 41 and the terminating resistor 42 is as shown in FIG. 7, the input resistor R2 as viewed from the detection circuit section 41 is _{substantially, R2 = 2r D x + R} D ... (5) Become. However, in equation (5), it is assumed that R _L >> _RD ... (6), so that the resistance value of the terminating resistor 42 is approximately infinite (the wire is disconnected). ).

[0033] This equation (5), the output voltage V2 is output to the detection circuit section 41, and _{V2 = R O E / (2r} D x + R D + R O) ... (7). Here, the distance x from the end of the pressure sensor 10 to the point X in FIG. 6 changes variously from 0 to L by changing the pressure application point, so that the output voltage V2 is
Distance according to a change in x, which varies from _{V2 = R O E / (R} D + R O) ... (8) to _{V2 = R O E / (2r} D L + R D + R O) ... (9). However, in any of the equations (7) to (9), unlike the equation (2), there is no _RL component, and as shown in the equation (6), _RL is much larger than _RD. Therefore, a large output change can be obtained between V1 (equation (2)) and V2 (equations (7) to (9)), so that the presence or absence of pressure application can be reliably detected. The distance x (that is, the position of the pressure application point) can be detected based on the magnitude of the output voltage V2 when the pressure is applied.

The terminating resistor 42 (R _L ) connecting the ends of the two conductive paths made up of the electrode members 22 and 23 has a failure detecting function for disconnection of the conductive path, and applies a predetermined voltage. By detecting the voltage drop at the terminating resistor 42 in the case of the above, it is possible to easily detect the presence or absence of energization even when no pressure is applied, and particularly to easily detect the disconnection when there is no energization. It is. However, as a result of using a conductive elastic body for the conductive path, the reliability against disconnection and the like becomes extremely high. Therefore, when a failure detection function for disconnection is not required, the terminating resistor 42 can be omitted.

When the pressure application to the pressure sensor 10 is released, the elastic conductive tube 21 and the composite member 2 are released.
Because the elastic restoring force 4 returns to the original state as shown in FIG. 1 and the like, the contact of the conductive path is easily switched from on to off.

As described above, according to this embodiment, the first, second, and fourth effects described above can be obtained in the same manner as in the first embodiment, and at any position in the longitudinal direction of the pressure sensor 10. The fifth effect of being able to detect whether pressure is applied can be obtained.

In this embodiment, the two electrode members 22,
Although the metal conductors 22a and 23a of the first and second electrode members 22 and 23a have a predetermined resistance value per unit length, the metal conductors 22a and 23a of one of the electrode members 22 and 23 have the same configuration.
a and 23a are constituted by the metal resistance conductors 22a and 23a, and the metal conductors 22a and 2
The 3a may be composed of a general metal wire such as a copper wire, or the flexible metal conductors 22a and 23a according to the first embodiment.

<Modification> FIGS. 8 and 9 are cross-sectional views showing a modification of the pressure sensor 10 according to the first and second embodiments described above. In the pressure sensor 10 shown in FIGS. 8 and 9, the first electrode member 22 and the second electrode member 23 are brought into direct contact with each other by applying pressure to electrically conduct. The presence or absence of pressure application can be detected by detecting the presence or absence of conduction between both electrode members 22 and 23, and at least one of metal conductors 22a and 22a of both electrode members 22 and 23 is detected. 23a
In the case where a metal resistance conductor having a predetermined resistance value per unit length is used, as in the second embodiment, it is formed by the two electrode members 22 and 23 via the pressure application point when applying pressure. Using the change in the resistance value of the closed circuit, it is possible to detect at which position in the longitudinal direction of the pressure sensor 10 the pressure is applied.

More specifically, the pressure sensor 10 of FIG.
A tube (elastic holding member) 51 formed of an elastic material such as rubber or the like, and a first tube (elastic holding member) 51 provided along the longitudinal direction of the tube 51 so as to be separated from each other in the tube 51. An electrode member 22 and a second electrode member 23 are provided.

Each of the electrode members 22 and 23 includes a metal electrode 22a and 23a having the same configuration as the metal electrodes 22a and 23a according to the first or second embodiment, and
elastic conductive members 22b, 2 made of conductive rubber or the like provided so as to cover the outer peripheral portions of the a and 23a and to fill the inner cavity of the tube body 51 while leaving a gap 52.
3b. In addition, both electrode members 22 and 23 are
In the internal space of the tube body 51, a predetermined interval (here, the gap 52) in the pressure application direction (here, the vertical direction).
It is provided with an opening.

When pressure is applied, the tube member 51 and each of the electrode members 22 and 23 are elastically deformed so as to be crushed, so that the two electrode members 22 and 23 come into contact with each other and are electrically connected to each other. It has become.

Here, in the pressure sensor 10 of FIG. 8, the second electrode member 23 of the elastic conductive member 22b of the first electrode member 22
And the opposing surface 54 of the elastic conductive member 23b of the second electrode member 23 with the first electrode member 22 has a uniform gap 52 with the opposing surface 53. It projects upward so as to be parallel to each other (to mesh with each other) in a substantially V-shaped cross section. For this reason,
In this modified example, even if pressure is applied from an oblique direction inclined with respect to the vertical direction, the two electrode members 22 and 23 surely come into contact with each other.

On the other hand, in the pressure sensor 10 shown in FIG.
The elastic conductive members 22b and 23b of the two electrode members 22 and 23 have a shape for a circular tube surrounding the metal conductors 22a and 23a.
Are provided at predetermined intervals from each other at the upper end and the lower end in the internal cavity 55. Further, the tube body 51 is
It has a cross-sectional shape in which the vertical height is slightly larger than the horizontal width. Further, a mounting portion 51a having a flat bottom surface is provided on a lower side surface portion of the tube body 51, and the mounting portion 51a can be fixed (or locked) to, for example, an inner peripheral portion of an automobile door. Has become.

In each of the above-described embodiments, the entire elastic conductive tube 21 is a conductive portion. However, only a part of the circumferential section may be a conductive portion. In this case, both electrode members 2
The elastic conductive tubes 21 and 23 need to be provided at positions where the elastic conductive tubes 21 can contact the conductive portions.
It is preferable to prevent the composite member 24 from rotating inside.

[0045]

According to the first and third aspects of the present invention, since the elastic conductive tube has a hollow shape, it can be elastically deformed relatively easily. Since the pressure is detected by detecting the presence or absence of conduction between the first electrode member and the second electrode member caused by the pressure, the pressure can be detected with high sensitivity with a relatively simple configuration. The first effect that a sensor can be provided is obtained.

By the way, conductive rubber or the like is generally used as the elastic conductive member. Such an elastic conductive member changes its resistance value due to deformation (elongation) due to temperature, humidity and external pressure. If the first electrode member and the second electrode member are constituted only by the members, the resistance values of both electrode members may become unstable, and the electrical characteristics of the pressure sensor may become unstable.

On the other hand, in the present invention, the first electrode member and the second electrode member cover at least a part of the elongated metal conductor having flexibility and the outer peripheral portion of the metal conductor in the circumferential direction. And an elastic conductive member provided along the longitudinal direction of the metal conductor, so that the resistance value of both electrode members is stabilized by the metal conductor, and the electrical characteristics of the pressure sensor are stabilized. The second effect of the present invention can be obtained.

Further, since flexible metal conductors are used for the first and second electrode members, the metal conductors impair the flexibility of the first and second electrode members and the pressure sensor. The pressure sensor can be sufficiently flexible, and as a result, the pressure sensor can be flexibly deformed and adapted to the application of the pressing force, and the pressure can be flexibly arranged and the like. The third effect is obtained that the degree of freedom of sensor arrangement can be increased.

Furthermore, since metal conductors are used for both electrode members, the connection between the two electrode members and the signal lines for signal extraction is performed by a simple connection method such as solder connection or crimp connection using the metal conductors. Can be easily and firmly performed.

Also in the inventions according to the second and third aspects, the presence or absence of pressure application is detected by detecting the presence or absence of electrical conduction between the first electrode member and the second electrode member caused by the elastic deformation of the elastic holding member. Therefore, the first effect described above can be obtained.

Also in the present invention, the first and second electrode members are provided with the metal conductor, so that the above-described second and fourth effects can be obtained.

Further, also in the present invention, since the metal conductors provided on the first electrode member and the second electrode member have flexibility, the above-described third effect can be obtained.

According to the third aspect of the present invention, the metal conductor provided on the first electrode member and the second electrode member is a stranded wire formed by twisting a plurality of metal wires, or has flexibility. Since the winding has the core material and the metal wire spirally wound around the outer periphery of the core material, the flexibility of the pressure sensor can be further improved.

According to the fourth and sixth aspects of the present invention,
Since the presence or absence of pressure application can be detected by detecting the presence or absence of electrical conduction between the first electrode member and the second electrode member via the conductive portion of the elastic conductive tube, the above-described first effect is obtained. Can be

Also in the present invention, the first and second electrode members are provided with the metal conductor, so that the above-described second and fourth effects can be obtained.

The metal conductor of at least one of the first electrode member and the second electrode member is a metal resistance conductor having a predetermined resistance value per unit length. The resistance value per unit length of at least one of the electrode members can be made uniform. Thereby, by connecting the signal lines for signal extraction to the ends of the first electrode member and the second electrode member, the first electrode member and the second electrode member are positioned at any position in the longitudinal direction by applying pressure. Since the resistance value between the ends of the two electrode members when viewed from the signal line side when conducting through the conductive portion of the elastic conductive tube changes according to the position where the pressing force is applied, the resistance between the two electrode members when the pressure is applied By detecting the magnitude of the flowing current or the like, a fifth effect that it is possible to detect at which position in the longitudinal direction of the pressure sensor the pressure is applied can be detected.

According to the fifth and sixth aspects of the present invention, the presence / absence of pressure application is determined by detecting the presence / absence of electrical continuity between the first electrode member and the second electrode member via the conductive portion of the elastic conductive tube. Since the detection can be performed, the above-described first effect can be obtained.

Also in the present invention, the first and second electrode members are provided with the metal conductor, so that the above-described second and fourth effects can be obtained.

Also in the present invention, the metal conductor of at least one of the first electrode member and the second electrode member is a metal resistance conductor having a predetermined resistance value per unit length. Therefore, the resistance value per unit length of at least one of the electrode members can be made uniform, and as a result, the above-described fifth effect can be obtained.

[Brief description of the drawings]

FIG. 1 is a cutaway perspective view of a pressure sensor according to a first embodiment of the present invention.

FIG. 2 is a diagram showing windings used in the pressure sensor of FIG.

FIG. 3 is a cross-sectional view showing a state when pressure is applied to the pressure sensor of FIG. 1;

FIG. 4 is a sectional view of the pressure sensor of FIG.

FIG. 5 is an equivalent circuit diagram showing an example of a connection relationship in a state where no pressure is applied between a pressure sensor according to a second embodiment of the present invention and a detection circuit unit connected to the pressure sensor.

FIG. 6 is a diagram showing a pressure application position when pressure is applied to a pressure sensor.

FIG. 7 is a diagram showing a state in which pressure is applied in the circuit diagram of FIG. 5;

FIG. 8 is a cross-sectional view of a modified example of the pressure sensor according to the first embodiment and the second embodiment.

FIG. 9 is a cross-sectional view of a modified example of the pressure sensor according to the first embodiment and the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Pressure sensor 21 Elastic conductive tube 22, 23 1st electrode member, 2nd electrode member 22a, 23a Metal conductor 22b, 23b Elastic conductive member 24 Composite member 31, 32 Side end insulator part 33 Central insulator part 41 Detection circuit part 42 Terminator 100 Core material 101 Metal wire

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01H 13/16 H01H 13/16 Z

Claims (6)

[Claims] 1. A tubular elastic conductive tube in which at least a part of a circumferential section is a conductive portion having conductivity, a first electrode member and a second electrode member provided along a longitudinal direction and separated from each other. An elongated composite member provided in the elastic conductive tube, the first electrode member and the second electrode member having a flexible elongated metal conductor and a metal thereof. An elastic conductive member provided along a longitudinal direction of the metal conductor so as to cover at least a part of a circumferential direction of an outer peripheral portion of the conductor, and the elastic conductive tube in a natural state of the elastic conductive tube. While placed away from the conductive part,
A pressure sensor, wherein the elastic conductive tube is arranged so as to be electrically connectable to each other via the conductive portion of the elastic conductive tube when the elastic conductive tube is elastically deformed by an external pressing force. 2. An elongated metal conductor having flexibility and an elastic conductive member provided along a longitudinal direction of the metal conductor so as to cover at least a part of a circumferential portion of an outer peripheral portion of the metal conductor. A first electrode member and a second electrode member each comprising: the first electrode member and the second electrode member are held in a separated state, while the first electrode member and the second electrode member are close to each other A pressure sensor comprising: an elastic holding member that elastically deforms when a pressing force is applied in a direction in which the first electrode member and the second electrode member contact each other. 3. The metal conductor is a stranded wire formed by twisting a plurality of metal wires, or comprises a flexible core material and a metal wire spirally wound around the outer periphery of the core material. The pressure sensor according to claim 1, wherein the pressure sensor is a winding. 4. A tubular elastic conductive tube in which at least a part of the section in the circumferential direction is a conductive portion having conductivity, a first electrode member and a second electrode member provided along the longitudinal direction and separated from each other. Having an electrode member, and an elongated composite member provided in the elastic conductive tube, wherein the first electrode member and the second electrode member are formed of an elongated metal conductor and an outer peripheral portion of the metal conductor. Elastic conductive members provided along the longitudinal direction of the metal conductor so as to cover at least a part of the section in the circumferential direction, and separated from the conductive portion of the elastic conductive tube in a natural state of the elastic conductive tube. On the other hand, when the elastic conductive tube is elastically deformed by a pressing force from the outside, the elastic conductive tube is arranged so as to be electrically connectable to each other via the conductive portion of the elastic conductive tube. Wherein the metal conductor of at least one of the first electrode member and the second electrode member is a metal resistance conductor having a predetermined resistance value per unit length. Sensor. 5. A first device comprising an elongated metal conductor and an elastic conductive member provided along a longitudinal direction of the metal conductor so as to cover at least a part of a circumferential portion of an outer peripheral portion of the metal conductor. An electrode member and a second electrode member, while pressing the first electrode member and the second electrode member in a separated state, and pressing the first electrode member and the second electrode member in a direction of approaching each other. Is applied, an elastic holding member that allows contact between the first electrode member and the second electrode member, and at least one of the first electrode member and the second electrode member. The pressure sensor, wherein the metal conductor of the electrode member is a metal resistance conductor having a predetermined resistance value per unit length. 6. The metal resistance conductor is a metal resistance wire or a resistance winding provided with a flexible core material and a metal resistance wire spirally wound around the outer periphery of the core material. The pressure sensor according to claim 4, wherein: