Pressure sensor

Abstract

A pressure sensor (100) comprises: a conductive fabric (10) having a conductive linear body (20) and non-conductive fibers (40); and a conductive member (30) provided at a position facing the conductive fabric (10). In the pressure sensor (100), when no external force is applied in a direction for the conductive member (30) to move toward the conductive fabric (10), the conductive linear body (20) and the conductive member (30) are separated by the non-conductive fibers (40) and are in an electrically insulated, non-conductive state, and when an external force is applied in the direction for the conductive member (30) to move toward the conductive fabric (10), at least a portion of the conductive member (30) pushes aside and moves through the non-conductive fibers (40), so that the conductive member (30) and the conductive linear body (20) are in an electrically connected, conductive state.

Description

Pressure sensor

[0001] The present invention relates to a pressure sensor.

[0002] Conventionally, a pressure sensor that can be detected by applying a force is known. For example, Patent Document 1 proposes a pressure sensor using a conductive fabric containing conductive yarns.

[0003] The conductive fabric disclosed in Patent Document 1 is provided with conductivity so that each conductive yarn of a plurality of conductive yarn regions arranged in parallel with each other across an insulating yarn region is electrically connected to each other, and is impregnated in the insulator of the conductive yarn. A conductive paste having a property of being electrically conductive to the core yarn is applied to form an electrode, and the electrode is configured to be connectable to a detection circuit.

[0004] Japanese Patent No. 6572420

[0005] For example, a pressure sensor using a conductive fabric obtains a conductive state by electrically connecting the conductive yarns in the conductive fabric when pressure is applied. A pressure sensor using a conductive fabric may include a holding member that prevents the conductive yarns from being electrically connected to each other in order to maintain a non-conductive state when no force is applied, i.e., in a non-pressurized state. This holding member is made of a non-conductive material and acts as a spacer. Such a pressure sensor may be deformed due to fatigue of the holding member. Therefore, a pressure sensor having a deformed holding member may be in a conductive state even in a non-pressurized state because the conductive yarns in the conductive fabric are electrically connected to each other, and may not function as a pressure sensor.

[0006] An object of the present invention is to provide a pressure sensor in which a non-conductive state and a conductive state can be stably obtained, respectively.

[0007] [1] A pressure sensor comprising: a conductive fabric having a conductive linear body and non-conductive fibers; and a conductive member provided at a position opposite to the conductive fabric, wherein when no external force is applied to the conductive member in a direction approaching the conductive fabric, the conductive linear body and the conductive member are separated by the non-conductive fibers and are in an electrically insulated, non-conductive state; and when an external force is applied to the conductive member in a direction approaching the conductive fabric, at least a part of the conductive member pushes aside the non-conductive fibers, so that the conductive member and the conductive linear body are electrically connected and in a conductive state.

[0008] [2] A pressure sensor according to [1], wherein the conductive linear body is a linear body containing a conductive thread.

[0009] [3] A pressure sensor according to [1] or [2], wherein the conductive linear body is a linear body containing carbon nanotubes.

[0010] [4] A pressure sensor according to [3], wherein the linear body containing carbon nanotubes is a twisted yarn containing carbon nanotubes.

[0011] [5] A pressure sensor according to [3], wherein the linear body containing carbon nanotubes is a composite yarn containing a resin linear body and carbon nanotubes wound around the outer circumference of the resin linear body.

[0012] [6] A pressure sensor according to any one of items [1] to [5], wherein the conductive fabric material comprises a pair of conductive linear bodies.

[0013] [7] A pressure sensor according to any one of items [1] to [6], wherein the conductive linear body comprises an electrode portion made of the conductive linear body and a wiring portion made of the conductive linear body.

[0014] [8] A pressure sensor according to any one of items [1] to [7], wherein the conductive member is a rubber-based material having a conductive portion.

[0015] [9] A pressure sensor according to any one of items [1] to [7], wherein the conductive member is a cloth material having a conductive portion composed of a conductive linear body.

[0016] According to one aspect of the present invention, a pressure sensor can be provided that can stably obtain both a non-conductive state and a conductive state.

[0017] This is a schematic perspective view showing an example of the main part of the pressure sensor according to this embodiment. This is a schematic cross-sectional view showing an example of the main part illustrating the non-conductive state of the pressure sensor according to this embodiment. This is a schematic cross-sectional view showing an example of the main part illustrating the conductive state of the pressure sensor according to this embodiment. This is a schematic diagram showing an example of a conductive linear body applied to the pressure sensor according to this embodiment. This is a schematic diagram showing another example of a conductive linear body applied to the pressure sensor according to this embodiment. This is a schematic plan view showing an example of a conductive fabric material applied to the pressure sensor according to this embodiment. This is a schematic plan view showing an example of a conductive member applied to the pressure sensor according to this embodiment. This is a schematic plan view showing another example of a conductive member applied to the pressure sensor according to this embodiment.

[0018] An example of a preferred embodiment of the present invention will be described with reference to the drawings. The present invention is not limited to the content of the embodiments. Note that some parts of the drawings have been enlarged or reduced in order to facilitate explanation.

[0019] [Pressure Sensor] A schematic perspective view shown in Figure 1 schematically represents an example of the main parts of the pressure sensor according to this embodiment. As shown in Figure 1, the pressure sensor 100 comprises a conductive fabric material 10 having conductive linear bodies 20 and non-conductive fibers 40, and a conductive member 30 provided at a position opposite the conductive fabric material 10. The conductive fabric material 10 shown in Figure 1 is composed of a knitted fabric with a three-layer structure of a first layer 11, a second layer 12, and a third layer 13, which are joined together, for example, by binding threads (not shown). The first layer 11 and the third layer 13 are composed of non-conductive fibers 40 in a similar structure. The second layer 12 is composed of non-conductive fibers 40 and conductive linear bodies 20, and comprises a pair of conductive linear bodies 20. The conductive linear bodies 20 contained in the second layer 12 are knitted so that they have a wave shape when viewed from above. Figure 1 shows the main parts of the pressure sensor 100 for the sake of simplicity. Therefore, although only the wave-shaped portion of the conductive linear body 20 is shown, the conductive linear body 20 has the form shown in Figure 4, which will be described later. That is, the conductive linear body 20 comprises an electrode portion made of the conductive linear body 20 and a wiring portion made of the conductive linear body 20.

[0020] The conductive member 30 is positioned on the first layer 11 side of the conductive fabric 10, with the second main surface 30B of the conductive member 30 facing the first main surface 10A of the conductive fabric 10. The arrangement of the conductive member 30 and the conductive fabric 10 is not limited to the arrangement shown in Figure 1. The conductive member 30 may be positioned on the third layer 13 side of the conductive fabric 10 instead of the first layer 11 side, and the second main surface 30B of the conductive member 30 may be configured to face the second main surface 10B of the conductive fabric 10. Here, the main surface refers to the largest surface of the conductive fabric 10, which faces in the thickness direction. For convenience, the terms "first main surface 10A" and "second main surface 10B" are used to clarify the positional relationship between one surface and the other surface of the conductive fabric material 10. However, depending on the configuration of the conductive fabric material 10, the first main surface 10A and the second main surface 10B of the conductive fabric material 10 can be used interchangeably, and the first main surface 10A and the second main surface 10B can be used without distinction from each other. Furthermore, if the entire conductive member 30 is conductive, or if both the first main surface 30A and the second main surface 30B of the conductive member 30 are conductive, the first main surface 30A and the second main surface 30B of the conductive member 30 can be used interchangeably, and the first main surface 30A and the second main surface 30B can be used without distinction from each other.

[0021] In the pressure sensor 100, when no force is applied to the conductive member 30 from the first main surface 30A towards the conductive fabric 10, and no external force is applied in a direction approaching the conductive fabric 10, the conductive linear body 20 and the conductive member 30 are separated by the non-conductive fibers 40 and are in an electrically insulated, non-conductive state (off state). However, when a force is applied to the conductive member 30 from the first main surface 30A towards the conductive fabric 10, and an external force is applied in a direction approaching the conductive fabric 10, at least a part of the conductive member 30 pushes aside the non-conductive fibers, causing the conductive member 30 and the conductive linear body 20 to be electrically connected, resulting in a conductive state (on state).

[0022] Here, "electrically insulated" means a state in which the conductive wire 20 and the conductive member 30 are not electrically connected. "Electrically connected" means a state in which the conductive wire 20 and the conductive member 30 are in physical contact and can conduct electricity, as well as a state in which the conductive wire 20 and the conductive member 30 can conduct electricity in close proximity without physical contact.

[0023] The schematic cross-sectional views shown in Figures 2A and 2B schematically represent examples of key parts for explaining the state of the pressure sensor 100 shown in Figure 1 when it is in a non-conductive or conductive state. Figure 2A shows the pressure sensor 100 when it is in a non-conductive state, and Figure 2B shows the pressure sensor 100 when it is in a conductive state. In Figures 2A and 2B, for the sake of simplicity, the illustration of the non-conductive fibers in the second layer 12 and the illustration of the third layer 13 are omitted.

[0024] As shown in Figures 2A and 2B, the first layer 11 of the conductive fabric 10 is made up of non-conductive fibers 40. The second layer 12 of the conductive fabric 10 is made up of non-conductive fibers (not shown) and conductive linear bodies 20. In the pressure sensor 100 shown in Figures 2A and 2B, in a cross-sectional view of the portion where the conductive linear body 20 is present, the conductive linear body 20 is arranged so as to be covered by two non-conductive fibers 40.

[0025] As shown in Figure 2A, when no force is applied to the conductive member 30 from the first main surface 30A toward the conductive fabric 10, the second main surface 30B of the conductive member 30 is in contact with the non-conductive fibers 40 in the conductive fabric 10. Therefore, the conductive linear body 20 is separated from the conductive member 30 by the non-conductive fibers 40 that constitute the first layer 11. Consequently, since the conductive member 30 is facing the conductive linear body 20 via the non-conductive fibers 40, the conductive member 30 and the conductive linear body 20 are electrically insulated and are in a non-conductive state (off state).

[0026] As shown in Figure 2B, when an external force F is applied to the conductive member 30 from the first main surface 30A side toward the conductive fabric 10, the conductive member 30 bends and deforms toward the conductive fabric 10. The non-conductive fibers 40 of the first layer 11 are pushed aside by the deformation of the conductive member 30, and at least a part of the conductive member 30 penetrates the conductive fabric 10. The second main surface 30B of the conductive member 30 comes into direct contact with or is close to the conductive linear body 20 contained in the second layer 12, electrically connecting the conductive member 30 and the conductive linear body 20, and the conductive linear body 20 and the conductive member 30 become conductive (on). When the external force F is removed, it returns to the state shown in Figure 2A, and the conductive linear body 20 and the conductive member 30 become non-conductive (off).

[0027] (Conductive Fabric) In Figures 1, 2A, and 2B, the conductive fabric 10 is configured as a three-layer structure, but is not limited thereto. The conductive fabric 10 may be a single-layer structure, a two-layer structure, or a multi-layer structure of four or more layers, as long as the conductive linear body 20 and the conductive member 30 can maintain a non-conductive state when no external force F is applied to the conductive member 30 in the direction toward the conductive fabric 10. From the viewpoint of enabling the conductive linear body 20 and the conductive member 30 to achieve a conductive state when an external force F is applied to the conductive member 30 in the direction toward the conductive fabric 10, the conductive fabric 10 is preferably a woven or knitted fabric. The woven fabric may be a single-layer or multi-layer woven fabric, and the knitted fabric may be a single-layer or multi-layer knitted fabric. From the viewpoint of enabling the conductive linear body 20 and the conductive member 30 to achieve a conductive state, the conductive fabric 10 is more preferably a single-layer or multi-layer knitted fabric. The weave structure of woven fabrics or knitted fabrics (woven and knitted structures are sometimes collectively referred to as woven-knit structures, and woven and knitted fabrics are sometimes collectively referred to as woven-knit fabrics) is not particularly limited, and known woven and knitted structures can be used. If the conductive fabric 10 is a woven fabric, examples of woven and knitted structures include plain weave, satin weave, and twill weave, and if the conductive fabric 10 is a knitted fabric, examples of weft knit, warp knit, and lace knit can be used. The woven and knitted structure of woven and knitted fabrics can be selected according to the sensitivity of the pressure sensor, etc.

[0028] The conductive fabric 10 is not limited to the embodiments shown in Figures 1, 2A, and 2B. For example, the following embodiments can be exemplified. The embodiments of the conductive fabric 10 shown below are illustrative, and the conductive fabric 10 is not limited to these. Note that the embodiments of the conductive fabric 10 shown in Figures 1, 2A, and 2B correspond to the embodiments when the conductive fabric 10 is a knitted fabric in the embodiment (iv) below.

[0029] (i): One embodiment of the conductive fabric 10 is a woven or knitted fabric composed of two layers. In this embodiment, the first layer is a woven or knitted fabric made of non-conductive fibers 40 as the base fabric, and the second layer is a woven or knitted fabric made of non-conductive fibers 40 as the base fabric. The conductive linear body 20 is not woven or knitted into either the first or second layer, and is secured by the yarn constituting either the first or second layer's woven or knitted fabric, or by a binding yarn connecting the first and second layers. In this embodiment, when no external force F is applied in the direction toward the conductive fabric 10, the conductive linear body 20 and the conductive member 30 are in a non-conductive state, as the conductive linear body 20 is positioned on the side that does not come into contact with the conductive member 30. Since the woven or knitted fabric of the layer to which the conductive linear body 20 is secured includes conductive parts, embodiment (i) is a conductive fabric.

[0030] (ii): One embodiment of the conductive fabric 10 uses a woven or knitted fabric as the base material, which is composed of a single-layer structure. In this embodiment, the conductive linear body 20 is not woven or knitted, and is fastened by threads that constitute the woven or knitted fabric made of non-conductive fibers 40. In this embodiment, when no external force F is applied in the direction toward the conductive fabric 10, the conductive linear body 20 and the conductive member 30 are in a non-conductive state, as the conductive linear body 20 is positioned on the side that does not come into contact with the conductive member 30. Since the surface on which the conductive linear body 20 is positioned includes conductive parts, embodiment (ii) is a conductive fabric.

[0031] (iii): One embodiment of the conductive fabric 10 is a woven or knitted fabric composed of two layers. In this embodiment, the first layer is a woven or knitted fabric made of non-conductive fibers 40, and the second layer is a woven or knitted fabric containing non-conductive fibers 40 and conductive linear bodies 20, with the conductive linear bodies 20 woven or knitted into the fabric. In this embodiment, when no external force F is applied in the direction toward the conductive fabric 10, the conductive linear bodies 20 and the conductive member 30 are in a non-conductive state, such that the conductive linear bodies 20 are positioned on the side that does not come into contact with the conductive member 30. Since the layer in which the conductive linear bodies 20 are woven or knitted contains conductive parts, embodiment (iii) is a conductive fabric.

[0032] (iv): One embodiment of the conductive fabric 10 is a woven or knitted fabric composed of three layers. In this embodiment, the first layer is a woven or knitted fabric made of non-conductive fibers 40, the second layer is a woven or knitted fabric containing non-conductive fibers 40 and conductive linear bodies 20, with the conductive linear bodies 20 woven or knitted into it, and the third layer is a woven or knitted fabric made of non-conductive fibers 40. Since the third layer, in which the conductive linear bodies 20 are woven or knitted, includes conductive parts, embodiment (iv) is a conductive fabric.

[0033] (v): One embodiment of the conductive fabric 10 is a known woven or knitted fabric composed of a single layer structure, to which a conductive linear body 20 is attached (for example, sewn) by a thread different from the threads that make up the woven or knitted fabric. In this embodiment, when no external force F is applied in the direction toward the conductive fabric 10, the conductive linear body 20 and the conductive member 30 are in a non-conductive state, such that the conductive linear body 20 is positioned on the side that does not come into contact with the conductive member 30. Since the surface on which the conductive linear body 20 is positioned includes a conductive portion, embodiment (v) is a conductive fabric.

[0034] (vi): One embodiment of the conductive fabric 10 is a known woven or knitted fabric composed of a single layer structure, to which a conductive linear body 20 is attached by yarn other than the yarn that constitutes the woven or knitted fabric, and a second layer, which is a known woven or knitted fabric composed of a single layer structure and does not contain the conductive linear body 20, is bonded and laminated to the side of the first layer on which the conductive linear body 20 is attached. Since the first layer on which the conductive linear body 20 is arranged includes conductive parts, embodiment (vi) is a conductive fabric.

[0035] In any of the embodiments described in (i) to (vi) above, the woven or knitted structure of the woven or knitted fabric is not particularly limited, and any known woven or knitted structure can be used. For example, in the example shown in Figures 2A and 2B, when the portion where the conductive linear body 20 is arranged is viewed in cross-section, the knitted structure of the conductive fabric 10 is configured such that one conductive linear body 20 is covered as if by two non-conductive fibers 40, but it is not limited to this. When the portion where the conductive linear body 20 is arranged is viewed in cross-section, the conductive fabric 10 may be configured such that, for example, one conductive linear body 20 is covered as if by one non-conductive fiber 40, or the knitted structure of the conductive fabric 10 may be configured such that one conductive linear body 20 is covered by three or more non-conductive fibers 40. That is, the number of non-conductive fibers 40 arranged on one conductive linear body 20 may be one, two, or three or more. The number of non-conductive fibers 40 arranged on a single conductive linear body 20 can be adjusted, for example, by the thickness (e.g., fineness) of the non-conductive fibers in the first layer 11 on the side where the conductive member 30 is arranged, the weave structure or knit structure of the woven or knitted fabric, and the thickness (e.g., fineness) of the conductive linear bodies in the second layer 12.

[0036] The non-conductive fibers 40 that constitute the conductive fabric material 10 are a concept that includes non-conductive threads. The non-conductive fibers 40 have a linear resistance of 1.0 × 10 ６The fibers exhibit a resistance of Ω / cm or higher. Linear resistance is determined by applying silver paste to both ends of the non-conductive fiber and measuring the resistance in the portion between the silver pastes to obtain the resistance value (unit: Ω) of the conductive fabric. The obtained resistance value can then be divided by the distance (cm) between the silver pastes to calculate the linear resistance. The non-conductive fibers 40 constituting the conductive fabric 10 may be natural fibers or synthetic fibers (including semi-synthetic fibers). The non-conductive fibers 40 may be one or more types of natural fibers in combination, or one or more types of synthetic fibers in combination. Examples of synthetic fibers include polyolefins, polyesters, polyamides, polyimides, acrylics, rayons, vinylon, and acetates. Examples of natural fibers include wool fibers, cotton fibers, and hemp fibers. It is preferable that the non-conductive fibers 40 are non-conductive yarns. If the non-conductive fibers 40 are non-conductive yarns, they may be single yarns, double yarns, blended yarns, or blended fiber yarns.

[0037] (Conductive Linear Body) The conductive linear body 20 is not particularly limited as long as it is conductive. The form of the conductive linear body 20 may be a linear body made only of a conductive material, or a linear body containing a conductive material. Examples of conductive materials include metals and carbon materials. The form of the conductive linear body 20 may be, for example, a linear body containing a metal wire, a linear body containing a conductive thread, or a twisted yarn thereof.

[0038] The metal wire may be a linear body made of a single metal wire, or a linear body made by twisting multiple metal wires together. Examples of metal wires include wires containing a single metal such as copper, aluminum, tungsten, iron, molybdenum, nickel, titanium, silver, and gold, or alloys containing two or more metals. Examples of metal wires include metal wires coated with metal plating or carbon material. Examples of conductive linear bodies 20 include linear bodies containing conductive fibers, linear bodies containing conductive particles, linear bodies with metal plating or vapor deposition applied to the surface, and linear bodies containing carbon nanotubes. Among these, the conductive linear body 20 is preferably a linear body containing conductive threads, and more preferably a linear body containing carbon nanotubes. The conductive linear body 20 has a linear resistance of 1.0 × 10⁻¹⁰, measured by the same measurement method as described above, except that silver paste is applied to both ends of the conductive linear body 20. ６ It is a linear body exhibiting a density of less than Ω / cm.

[0039] One embodiment of a linear body containing carbon nanotubes is a twisted yarn containing carbon nanotubes. The twisted yarn containing carbon nanotubes may be a twisted yarn made only of carbon nanotubes, a composite yarn made of twisted carbon nanotubes and conductive fibers other than carbon nanotubes, or a composite yarn made of twisted carbon nanotubes and non-conductive fibers. Another embodiment of a linear body containing carbon nanotubes is a composite yarn containing carbon nanotubes. The composite yarn containing carbon nanotubes may be a composite yarn made of twisted carbon nanotubes and conductive fibers other than carbon nanotubes, or a composite yarn made of twisted carbon nanotubes and non-conductive fibers. Furthermore, the linear body containing carbon nanotubes may be a composite yarn containing carbon nanotubes, and may be a composite yarn (so-called covering yarn) that includes a resin linear body and carbon nanotubes wound around the outer circumference of the resin linear body.

[0040] Referring to FIG. 3A here, FIG. 3A schematically shows a conductive linear body 21 as an example of the conductive linear body 20. As shown in FIG. 3A, the conductive linear body 21 is a twisted yarn composed only of carbon nanotubes 2A, and a plurality of carbon nanotubes 2A are twisted in an S twist (right twist) to form the conductive linear body 21. The carbon nanotubes 2A may be any of multi-walled carbon nanotubes (MWCNT), double-walled carbon nanotubes (DWCNT), and single-walled carbon nanotubes (SWCNT), or a mixture thereof. The twisted yarn composed only of carbon nanotubes 2A is not limited to the S twist shown in FIG. 3A and may be a Z twist (left twist). Further, the twisted yarn composed only of carbon nanotubes 2A may be twisted and combined by an up twist (Z twist or S twist) in a direction opposite to the direction of the down twist (S twist or Z twist). The twisted yarn composed only of carbon nanotubes 2A can be obtained by a known manufacturing method.

[0041] Next, referring to FIG. 3B, FIG. 3B schematically shows a conductive linear body 22 as another example of the conductive linear body 20. As shown in FIG. 3B, the conductive linear body 22 includes a resin linear body 2B as a core yarn and carbon nanotubes 2A as sheath yarns wound around the outer periphery of the resin linear body 2B. The conductive linear body 22 is formed by continuously winding the carbon nanotubes 2A in a helical shape on the outer peripheral surface of the resin linear body 2B such that the carbon nanotubes 2A adjacent to each other in the length direction of the resin linear body 2B are separated from each other. In the conductive linear body 22, the winding direction of the carbon nanotubes 2A around the resin linear body 2B is the S twist direction (right twist direction).

[0042] The composite yarn containing carbon nanotubes 2A wound around the outer circumference of the resin wire 2B is not limited to the composite yarn shown in Figure 3B. For example, the carbon nanotubes 2A may be continuously wound in a helical manner around the outer surface of the resin wire 2B to suppress the gaps between adjacent carbon nanotubes 2A in the longitudinal direction of the resin wire 2B and make them denser. The winding direction of the carbon nanotubes 2A around the resin wire 2B may be the Z-twist direction (left-hand twist direction). Furthermore, the embodiment of the composite yarn containing carbon nanotubes 2A wound around the outer circumference of the resin wire 2B may also be one of the embodiments exemplified below, although these are not shown in the figures.

[0043] One embodiment of a composite yarn containing carbon nanotubes 2A wound around the outer circumference of a resin wire 2B is to use two carbon nanotubes, in which a first carbon nanotube is wound around the resin wire in a first twisting direction and a second carbon nanotube is wound around it in a second twisting direction, and the first twisting direction and the second twisting direction may be the same direction. In this case, both the first twisting direction and the second twisting direction may be S-twist directions or both may be Z-twist directions. Another embodiment of a composite yarn containing carbon nanotubes 2A wound around the outer circumference of a resin wire 2B is to use two carbon nanotubes, in which a first carbon nanotube is wound around the resin wire in a first twisting direction and a second carbon nanotube is wound around it in a second twisting direction, and the first twisting direction and the second twisting direction may be different directions. In this case, if the first twisting direction is the S-twist direction (or Z-twist direction), the second twisting direction will be the Z-twist direction (or S-twist direction). One embodiment of a composite yarn containing carbon nanotubes 2A wound around the outer circumference of a resin wire 2B may use three or more carbon nanotubes, and the three or more carbon nanotubes may be wound around the resin wire in the first twisting direction, the second twisting direction, and the third twisting direction. The first twisting direction, the second twisting direction, and the third twisting direction may be the same as each other, or they may be different as well, or any two of the twisting directions may be the same and the remaining twisting direction may be different. The first twisting direction, the second twisting direction, and the third twisting direction may be wound in predetermined winding directions.

[0044] The resin linear body 2B may be a conductive resin linear body or a non-conductive resin linear body. The resin linear body 2B is preferably non-conductive. The resin linear body 2B is a concept including a thread. The resin linear body 2B may be a non-conductive thread. The resin linear body 2B may be, for example, a non-conductive thread containing a thermoplastic resin. The resin constituting the resin linear body 2B is not particularly limited, and examples thereof include various thermoplastic resins such as polyolefin, polyester, polyacrylic, polystyrene, polyimide, polyimide amide, polyamide, polyurethane, polycarbonate, polyarylate, phenoxy, and urethane. In addition, the resin constituting the resin linear body 2B also includes various thermosetting resins such as an epoxy resin composition. The resin constituting the resin linear body 2B can use one or more of these resins.

[0045] If the conductive linear body 20 is a linear body composed only of a conductive material, the conductive member 30 that pushes aside the non-conductive fibers and enters the conductive cloth material can more easily make electrical contact with the conductive linear body 20, so a conductive state can be easily obtained. From this perspective, the conductive linear body 20 is preferably a linear body composed only of a conductive material. Among the linear bodies composed only of a conductive material, if it is a twisted thread composed only of carbon nanotubes 2A, since the carbon nanotubes 2A themselves are excellent in durability and flexibility, for example, compared with a linear body having a metal plating on the surface, it is considered that a resistance change due to plating peeling and corrosion is suppressed. Also, if it is a twisted thread composed only of carbon nanotubes 2A, since it has flexibility, it is considered that it can withstand various processes. From this perspective, the conductive linear body 20 is preferably a twisted thread composed only of carbon nanotubes 2A.

[0046] If the conductive linear body 20 is a composite yarn containing carbon nanotubes 2A wound around the outer circumference of a resin linear body 2B, the overall thickness of the composite yarn can be easily adjusted by adjusting the thickness (e.g., fineness) of the resin linear body 2B. By adjusting the overall thickness of the composite yarn, the conductivity state can be easily adjusted by varying the strength of the pressure (external force F shown in Figure 2B). From this viewpoint, it is also preferable that the conductive linear body 20 is a composite yarn containing carbon nanotubes 2A wound around the outer circumference of a resin linear body 2B.

[0047] Referring to Figure 4, an example is shown in a plan view of the conductive fabric material 10 from the first layer 11 side (i.e., the first main surface 10A side shown in Figure 1, etc.). As shown in Figure 4, the conductive fabric material 10 has a pair of conductive linear bodies 20 in the second layer 12. Each pair of conductive linear bodies 20 comprises an electrode portion 20A made of the conductive linear body 20 and a wiring portion 20B made of the conductive linear body 20 that is electrically connected to the electrode portion 20A. In a plan view, the wiring portion 20B is formed in a corrugated shape by the conductive linear body 20. In a plan view, the electrode portion 20A is formed in a rectangular shape by repeatedly bending or curving the conductive linear body 20 at 180°. Since the conductive linear body 20 extends from the wiring portion 20B to the electrode portion 20A, the wiring portion 20B made of the conductive linear body 20 and the electrode portion 20A made of the conductive linear body 20 are formed in a continuous manner.

[0048] The conductive linear bodies 20 in the conductive fabric are not limited to a pair of conductive linear bodies 20 as shown in Figures 1 and 4. For example, as shown in Figures 2A and 2B, if the conductive linear bodies 20 and the conductive member 30 can be switched between an on state and an off state depending on the presence or absence of an external force F, the number, structure, and shape of the conductive linear bodies 20 are not particularly limited. For example, the conductive fabric 10, which has a structure comprising an electrode portion 20A made of conductive linear bodies 20 and a wiring portion 20B made of conductive linear bodies 20 that is electrically connected to the electrode portion 20A, can adopt various forms. The number of electrode portions 20A and wiring portions 20B is not limited to the number shown in Figure 4 and can be configured according to the purpose. The shape of the electrode portions 20A and wiring portions 20B is also not limited to the number shown in Figure 4 and can be configured according to the purpose.

[0049] For example, the conductive fabric material 10 can be configured such that it has one conductive linear body 20 in the second layer and one conductive linear body 20 in the third layer, and that the conductive fabric material 10 is configured such that, by an external force F shown in Figure 2B, the conductive linear body 20 in the second layer, the conductive linear body 20 in the third layer, and the conductive member 30 are electrically connected to obtain a conductive state.

[0050] (Conductive Member) As shown in Figures 2A and 2B, the conductive member 30 is not particularly limited as long as the conductive linear body 20 and the conductive member 30 are made of materials that can switch between an on state and an off state depending on the presence or absence of an external force F. In this respect, it is preferable that the conductive member 30 is flexible. Here, the flexibility of the conductive member 30 can be evaluated, for example, by placing a conductive member 30 of a certain thickness for flexibility evaluation horizontally on two support points set at a certain distance apart, and using a tensile testing machine, lowering a wedge-shaped jig from the upper part near the center of the conductive member 30 for flexibility evaluation at a constant descent speed, performing a three-point bending test, and measuring the amount of displacement of the test piece at the time of fracture. In this evaluation, the larger the amount of displacement, the better the flexibility can be judged to be.

[0051] The conductive member 30 has a surface resistance of 1.0 × 10, measured using the same measurement method as described above, except that silver paste is applied to both ends of the conductive portion of the conductive member 30. ８ Ω / cm ２ This component indicates a value less than [amount].

[0052] From the viewpoint of enabling both an ON state and an OFF state depending on the presence or absence of an external force F, it is preferable that the conductive member 30 is a rubber-based material having a conductive portion. If the conductive member 30 is a rubber-based material having a conductive portion, the rubber-based material only needs to have a conductive portion in at least a part of it, as long as the conductive wire 20 and the conductive member 30 can obtain an ON state and an OFF state depending on the presence or absence of an external force F. In this case, the conductive portion is provided at least on the side of the conductive member 30 that is positioned on the conductive fabric material 10 (for example, at least the second main surface 30B side shown in Figures 1, 2A and 2B). If the conductive member 30 is a rubber-based material having a conductive portion, the conductive wire 20 and the conductive member 30 can be easily electrically connected by an external force F, and it becomes easy to obtain an ON state and an OFF state depending on the presence or absence of an external force F. In rubber-based materials having conductive parts, it is preferable that the entire rubber-based material is conductive, from the viewpoint of easily obtaining an electrically conductive state (conductive state). In the view that an external force F can push aside the non-conductive fibers 40 from many locations, it is preferable that the conductive part has a shape that allows it to be electrically connected to the conductive linear body 20 in the conductive fabric material 10 over a range of 5 mm or more. Since the conductive part can be electrically connected to the wiring part 20B composed of the conductive linear body 20 in the conductive fabric material 10 by an external force F, it is more preferable that the shape of the conductive part electrically contacts the wiring part 20B composed of the conductive linear body 20 over a range of 5 mm or more in the direction in which the wiring part 20B composed of the conductive linear body 20 extends, and has a shape that is 50 times or more the diameter of the conductive linear body 20 in the direction perpendicular to the direction in which the wiring part 20B composed of the conductive linear body 20 extends (the width direction of the wiring part 20B).

[0053] Examples of rubber materials for rubber-based materials having conductive parts include at least one selected from the group consisting of silicone rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, chloroprene rubber, nitrile rubber, polyisobutylene, ethylene propylene rubber, chlorosulfonated polyethylene, acrylic rubber, fluororubber, epichlorohydrin rubber, and urethane rubber. The conductive part may, for example, contain conductive materials such as conductive particles in the rubber-based material. The conductive part can also be formed, for example, by applying conductive ink or the like to the rubber-based material.

[0054] From the viewpoint of enabling the conductive linear body 20 and the conductive member 30 to switch between an on state and an off state depending on the presence or absence of an external force F, it is also preferable that the conductive member 30 is a cloth material having a conductive portion made of a conductive linear body. When the conductive member 30 is a cloth material having a conductive portion made of a conductive linear body, it is preferable that it is different from the conductive cloth material 10. For example, when the conductive member 30 is a cloth material having a conductive portion made of a conductive linear body, it is preferable that the conductive portion is exposed on the surface of the conductive member 30.

[0055] Referring to Figures 5A and 5B, Figures 5A and 5B show schematic diagrams of conductive members 30, respectively, where the conductive member 30 shown in Figure 1 is a fabric material having a conductive portion composed of conductive linear bodies. Specifically, Figures 5A and 5B are schematic diagrams of the conductive member 30 shown in Figures 1, 2A, and 2B, respectively, viewed from the second main surface 30B side. As shown in Figure 5A, the conductive member 31 comprises a fabric material 33 and a planar conductive portion 34A composed of conductive linear bodies 34. The fabric material 33 is not particularly limited, and known woven fabrics and nonwoven fabrics can be used. The conductive linear bodies 34 constituting the conductive portion 34A may be selected from the materials described above for the conductive linear body 20. The conductive portion 34A is formed into a rectangular shape by repeatedly bending or curving the conductive linear bodies 34 at 180° in a plan view. The conductive portion 34A can be formed in the same manner as the electrode portion 20A, which is composed of the conductive linear body 20 described in Figure 4 above. The conductive portion 34A of the conductive member 31 may be fastened by the fibers (including threads) that make up the fabric material 33, or it may be fastened to the fabric material 33 by another thread.

[0056] As shown in Figure 5B, the conductive member 32 comprises a fabric material 33 and a linear conductive portion 34B composed of a conductive linear body 34. The conductive portion 34B is formed in a corrugated shape. The conductive portion 34B may be composed of a material selected from the conductive linear body 20 in the conductive fabric material 10 described above. The conductive portion 34B of the conductive member 32 may be fastened by the fibers (including threads) that make up the fabric material 33, or it may be fastened to the fabric material 33 by another thread.

[0057] From the viewpoint of making it easier to obtain a conductive state even when the external force F is small, if the conductive member 30 shown in Figures 1, 2A, and 2B is a cloth material having conductive parts 34A and 34B composed of conductive linear bodies 34 shown in Figures 5A and 5B, it is preferable that the conductive member 30 is a cloth material having a conductive part 34A formed in a planar shape composed of conductive linear bodies 34. If the conductive member 30 shown in Figures 1, 2A, and 2B is the conductive member 31 shown in Figure 5A (i.e., a cloth material having a planar conductive part 34A composed of conductive linear bodies 34), it is considered that the non-conductive fibers 40 can be pushed apart from many places by the external force F, so that the conductive member 31 and the conductive linear bodies 20 in the conductive cloth material 10 (see Figures 1, 2A, and 2B) are easily electrically connected. Also, the on state and the off state can be easily obtained depending on whether or not an external force F is applied to the conductive member 31. The planar conductive portion 34A is not limited to the form shown in Figure 5A. The planar conductive portion 34A may be formed as a rectangle with adjacent conductive linear bodies 34 that are repeatedly bent or curved at 180° in a plan view and spaced apart, or it may be formed as a rectangle with adjacent conductive linear bodies 34 that are closely spaced.

[0058] The dimensions of the planar conductive portion 34A are preferably such that they allow for electrical connection to the conductive linear body 20 over a range of 5 mm or more. The planar conductive portion 34A can be electrically connected to the wiring portion 20B composed of the conductive linear body 20 by an external force F. For this reason, the dimensions of the planar conductive portion 34A are such that they electrically contact the wiring portion 20B composed of the conductive linear body 20 over a range of 5 mm or more in the direction in which the wiring portion 20B composed of the conductive linear body 20 extends, and it is more preferable that the dimensions in the width direction of the wiring portion 20B composed of the conductive linear body 20 are 50 times or more the diameter of the conductive linear body 20. Here, as an example of dimensions that allow for electrical connection to the conductive linear body 20 over a range of 5 mm or more, if the dimensions of the planar conductive portion 34A are 5 mm or more per side, then 5 mm or more means that the length from one end to the other end of the first side of the conductive portion 34A is 5 mm or more, and the length from one end to the other end of the second side perpendicular to the first side is 5 mm or more. In the conductive portion 34A, the length of the first side is the length from the starting end of the conductive linear body 34 for forming the planar conductive portion 34A to the point in plan view before the conductive linear body 34 is first repeatedly bent or curved at 180°. The second side is the portion perpendicular to the first side, and is the distance between the point where the conductive linear body 34 is first repeatedly bent or curved at 180° and the end of the conductive linear body 34 for forming the planar conductive portion 34A. In other words, the second side is the length that includes portions that do not have the conductive linear body 34.

[0059] The fabric material having a conductive portion composed of conductive linear bodies is not limited to the embodiments shown in Figures 5A and 5B. For example, the conductive fabric material 10 shown in Figure 1 may have an embodiment that includes either the first layer 11 or the third layer 13, or an embodiment that does not include either the first layer 11 or the third layer 13.

[0060] (Effects of the Embodiment) According to this embodiment, the following effects can be achieved. (1) According to this embodiment, when no external force F is applied in the direction that the conductive members 30, 31, and 32 approach the conductive fabric material 10, the conductive linear body 20 in the conductive fabric material 10 and the conductive members 30, 31, and 32 are separated by the non-conductive fibers 40 in the conductive fabric material 10. Therefore, in the non-pressurized state of the pressure sensor 100, the conductive linear body 20 and the conductive members 30, 31, and 32 can stably maintain an electrically insulated non-conductive state (off state). Therefore, according to this embodiment, an electrically insulated non-conductive state can be stably obtained in the non-pressurized state without providing a holding member that functions as a spacer. (2) According to this embodiment, when an external force F is applied in a direction that brings the conductive members 30, 31, and 32 closer to the conductive fabric 10, at least a portion of the conductive members 30, 31, and 32 push aside the non-conductive fibers 40 in the conductive fabric 10, thereby creating an electrically connected state (on state) between the conductive linear body 20 in the conductive fabric 10 and the conductive members 30, 31, and 32. Therefore, when the pressure sensor 100 is pressurized, a stable electrically connected state can be obtained between the conductive linear body 20 and the conductive members 30, 31, and 32. (3) By selecting the woven structure, the thickness (e.g., fineness) of the non-conductive fibers that constitute the conductive fabric 10, selecting the type and thickness (e.g., fineness) of the conductive linear body 20 in the conductive fabric 10, selecting the type of conductive members 30, 31, and 32, and by combinations of these selections, the sensitivity of the conductivity state depending on the strength of the external force F can be adjusted. (4) According to this embodiment, the effects described in (1) to (3) above can be achieved, and therefore the pressure sensor 100 can be applied to various sensors that are required to detect pressure.

[0061] [Modifications of Embodiments] The present invention is not limited to the embodiments described above, and any modifications or improvements that can achieve the objectives of the present invention are included in the present invention.

[0062] For example, the conductive fabric material 10 may be provided with wiring (not shown), and the information detected by the pressure sensor 100 may be measured by a measuring device (not shown) through the wiring.

[0063] The present invention will be described in more detail below with reference to examples. The present invention is not limited to these examples.

[0064] The pressure sensors obtained in each example were evaluated as follows.

[0065] [Conductivity Evaluation] Wiring was attached to the two electrode sections of the pressure sensor fabricated in each example, and the presence or absence of continuity between the electrodes was checked using a tester (Kyoritsu Electrical Instruments Co., Ltd., "Digital Multimeter MODEL 1008"). When no continuity could be confirmed under no pressure (non-pressurized), it was judged as a non-conductive state and evaluated as "A". Conversely, when continuity could be confirmed under no pressure, it was judged as a conductive state and evaluated as "F".

[0066] Next, a 14 mmφ push-pull gauge jig (Aiko Engineering Co., Ltd., "Digital Push-Pull Gauge RX-5") was pressed against the conductive material of each pressure sensor, and when pressure was applied from the conductive material towards the conductive fabric (pressurized), the presence or absence of continuity between the electrodes was checked in the same way as when no pressure was applied. The conductivity was evaluated from the pressure at which continuity occurred according to the following evaluation criteria. <Evaluation Criteria> G1: 1N or more, less than 5N. G2: 5N or more, less than 10N. G3: 10N or more, less than 20N. G4: 20N or more, less than 50N. G5: 50N or more.

[0067] <Experimental Examples 1 to 5> Various pressure sensors were fabricated using conductive fabric and conductive components prepared as described below, in the combinations shown in Tables 1 and 2.

[0068] (Preparation of conductive fabric) A three-layer knitted fabric was prepared as the conductive fabric. The three-layer knitted fabric is a three-layer knitted fabric as shown in Figure 1, in which a first layer of knitted fabric made of non-conductive fibers, a second layer of knitted fabric in which conductive wires containing non-conductive fibers and conductive wires, having electrode parts and wiring parts as shown in Figure 4, are knitted, and a third layer of knitted fabric made of non-conductive fibers are joined together with binding yarn. For the first and third layers, covering yarn was prepared using polyester as the core yarn and nylon as the sheath yarn as the non-conductive fibers, and the knitted fabric was made using this covering yarn. For the second layer, when making the knitted fabric using the covering yarn as the non-conductive fibers used for the first and third layers, conductive wires were knitted along the direction of knitting of the second layer. The part in which the conductive wires were knitted in a wave shape was made into the wiring part, and the part in which they were knitted by repeatedly bending them so that they form a rectangular surface when viewed from above was made into the electrode part. Then, by changing the type of conductive wire and the combination of fineness of the covering yarn used when making the knitted fabric, the following conductive fabric materials were produced.

[0069] "C30-1": When preparing the knitted fabric for the first and third layers, the above-mentioned covering yarn with a fineness of 30 denier was used as the non-conductive fiber. When preparing the knitted fabric for the second layer, the same covering yarn as in the first and third layers was used as the non-conductive fiber, and a twisted yarn made by twisting together eight carbon nanotube threads was used as the conductive linear body. The fabric was then knitted so that the above-mentioned covering yarns from the first and third layers were arranged on one conductive linear body in the second layer, resulting in a three-layer knitted fabric.

[0070] "C30-2": A knitted fabric with a three-layer structure was created in the same manner as C30-1, except that the covering yarn, which is placed on one conductive linear body of the second layer, was changed to be placed on two strands.

[0071] "C30-4": Except for the change in C30-1, where the coverings arranged on one conductive linear body of the second layer are arranged in four sections, the knitted fabric was made in the same manner as C30-1, but with a three-layer structure.

[0072] "C50-2": In C30-1, when producing the knitted fabric of the first, second, and third layers, the above covering yarn with a fineness of 50 denier was used as the non-conductive fiber, and the covering that was placed on one conductive linear body of the second layer was changed to be arranged in two strands, otherwise the process was the same as in C30-1 to produce a three-layer knitted fabric.

[0073] "C30-2-C2": In C30-1, the second layer was constructed in the same manner as C30-1, except that a covering yarn was used in which two carbon nanotube yarns were wrapped around the outer circumference of the polyester yarn, with a polyester yarn as the core yarn and two carbon nanotube yarns as the sheath yarns, so that two coverings were arranged on one conductive linear body of the second layer.

[0074] "C30-2-Ag": In C30-1, the structure is the same as C30-1, except that silver-plated yarn, which is polyester yarn coated with silver, is used as the conductive linear body for the second layer, and two coverings are arranged on one conductive linear body of the second layer.

[0075] (Preparation of conductive material) A 10 mm square rectangular conductive rubber material was prepared as a rubber material having a conductive portion. This conductive rubber material is a rubber material in which carbon black is mixed as a conductive material with silicone rubber. The surface resistance is 4 × 10 ６ Ω / cm ２ In Tables 1 and 2, the rubber-based material is referred to as "C-rub".

[0076] As a fabric material having a conductive portion composed of conductive linear bodies, a fabric material corresponding to the structure of the aforementioned conductive fabric material was prepared, in which the first layer is absent and the second layer is configured as the surface. Specifically, a fabric material having a conductive portion was prepared as follows.

[0077] "Ag-P": As a non-conductive fiber, a covering yarn was prepared with polyester as the core yarn and nylon as the sheath yarn, and a first layer was prepared by knitting with this covering yarn. As a non-conductive fiber, a covering yarn with polyester as the core yarn and nylon as the sheath yarn, and as a conductive linear body, a silver-plated yarn made by silver-plating polyester yarn was prepared, and a second layer was prepared by knitting with this covering yarn and the silver-plated yarn made by silver-plating polyester yarn. A knitted fabric with a two-layer structure was then made by joining the first layer and the second layer with a binding yarn. The second layer was configured to be placed on the surface of the layer facing the conductive fabric material. When making the knitted fabric of the second layer, the silver-plated yarn made by silver-plating polyester yarn was knitted along the direction of knitting of the second layer, and further, when knitting the fabric, it was repeatedly bent and knitted so that it would form a rectangular surface of 10 mm square when viewed from above, as shown in Figure 5A. The part knitted to form a rectangular surface is the conductive part.

[0078] "CNT-P": A two-layer knitted fabric was prepared in the same manner as Ag-P, except that a twisted yarn made by twisting eight carbon nanotube threads together was used as the conductive linear body.

[0079] "Ag-L": In Ag-P, a two-layer knitted fabric was prepared in the same manner as Ag-P, except that the silver-plated yarn, which is polyester yarn coated with silver plating, was knitted into a single 5 mm wide linear shape with the conductive part being a wavy linear shape as shown in Figure 5B.

[0080] As another conductive material, a 10 mm square rectangular copper foil was prepared. In Tables 1 and 2, this copper foil is denoted as "Cu-f".

[0081]

[0082]

[0083] As shown in Table 1, under non-pressurized conditions, all of the pressure sensors fabricated in Experimental Examples 1 to 5 maintain a non-conductive state (off state). From the results of these experiments, it was confirmed that a stable electrically insulated non-conductive state can be obtained under non-pressurized conditions without the use of spacers.

[0084] On the other hand, as shown in Table 2, it can be seen that under pressurized conditions, the pressure required for conductivity can be changed by the combination of the conductive member and the conductive fabric. In Experimental Example 5, where copper foil is used as the conductive member, it is difficult to deform under applied pressure, and even if it is deformed under applied pressure, it is difficult to push aside the non-conductive fibers of the conductive fabric. Therefore, it is difficult to obtain conductivity, and a large pressure is required to obtain conductivity. In contrast, in Experimental Examples 1 to 4, where a conductive rubber-based material with a conductive part or a fabric material with a conductive part is used as the conductive member, the conductive member deforms more easily with less pressure compared to Experimental Example 5 using copper foil, so it is possible to push aside the non-conductive fibers of the conductive fabric. For this reason, the pressure sensors in Experimental Examples 1 to 4 can easily obtain a stable conductivity. Furthermore, from the results of Experimental Examples 1 to 4, it can be seen that the pressure required to obtain conductivity can be adjusted by the number of non-conductive fibers placed on a single conductive linear body in the conductive fabric. Furthermore, the results from Experimental Examples 1 to 4 show that the pressure required to achieve an electrically conductive state can be adjusted by combining conductive fabric material and conductive components.

[0085] From the above results, it was confirmed that the pressure sensor according to this embodiment can stably obtain both a non-conductive state and a conductive state. Furthermore, the sensitivity of the pressure sensor according to this embodiment can be easily adjusted by combining a conductive fabric material and a conductive member.

[0086] 10...Conductive fabric material, 10A...First main surface (conductive fabric material), 10B...Second main surface (conductive fabric material), 11...First layer, 12...Second layer, 13...Third layer, 20, 21, 22...Conductive wire, 2A...Carbon nanotube, 2B...Resin wire, 20A...Electrode part, 20B...Wiring part, 30, 31, 32...Conductive member, 30A...First main surface (conductive member), 30B...Second main surface (conductive member), 33...Fabric material, 34...Conductive wire, 34A, 34B...Conductive part, 40...Non-conductive fiber, 100...Pressure sensor, F...External force.

Claims

1. A pressure sensor comprising: a conductive fabric having a conductive linear body and non-conductive fibers; and a conductive member provided at a position opposite to the conductive fabric, wherein when no external force is applied to the conductive member in a direction approaching the conductive fabric, the conductive linear body and the conductive member are separated by the non-conductive fibers and are in an electrically insulated, non-conductive state; and when an external force is applied to the conductive member in a direction approaching the conductive fabric, at least a part of the conductive member pushes aside the non-conductive fibers, so that the conductive member and the conductive linear body are electrically connected and in a conductive state.

2. A pressure sensor according to claim 1, wherein the conductive linear body is a linear body containing a conductive thread.

3. A pressure sensor according to claim 1 or claim 2, wherein the conductive linear body is a linear body containing carbon nanotubes.

4. A pressure sensor according to claim 3, wherein the linear body containing carbon nanotubes is a twisted yarn containing carbon nanotubes.

5. A pressure sensor according to claim 3, wherein the linear body containing carbon nanotubes is a composite yarn comprising a resin linear body and carbon nanotubes wound around the outer circumference of the resin linear body.

6. A pressure sensor according to claim 1 or claim 2, wherein the conductive fabric material comprises a pair of conductive linear bodies.

7. A pressure sensor according to claim 1 or claim 2, wherein the conductive linear body comprises an electrode portion made of the conductive linear body and a wiring portion made of the conductive linear body.

8. A pressure sensor according to claim 1 or claim 2, wherein the conductive member is a rubber-based material having a conductive portion.

9. A pressure sensor according to claim 1 or claim 2, wherein the conductive member is a cloth material having a conductive portion composed of a conductive linear body.

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