Capacitive sensor

Abstract

The purpose of the present invention is to provide a capacitive sensor that can achieve both thinness and strength.　A capacitive sensor (1) comprises a first electrode body (10) and a second electrode body (20). In the capacitive sensor (1), the first electrode body (10) and the second electrode body (20) are formed into at least one linear shape on the same plane. The first electrode body (10) and the second electrode body (20) are arranged parallel to each other at a prescribed interval in a direction intersecting the direction in which the capacitive sensor (1) expands and contracts.

Description

Capacitive sensor

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

[0002] As a sensor for detecting expansion / contraction, bending, and distortion applied to a detection object, a capacitive sensor is known. The capacitive sensor includes a capacitance portion obtained by laminating a pair of electrode layers on both surfaces of a dielectric layer. The capacitive sensor detects a change in capacitance due to expansion / contraction, bending, and distortion occurring in the detection object in the capacitance portion (see, for example, Patent Documents 1 and 2).

[0003] Japanese Patent Application Laid-Open No. 2023-3244, Japanese Patent Application Laid-Open No. 2018-96797

[0004] By the way, the capacitive sensor laminates an insulating layer and a pair of conductive layers as a voltage application layer and a ground layer by a method such as screen printing. The capacitive sensor is required to form the dielectric layer to a thickness of, for example, 100 μm or less so as to have more capacitance values.

[0005] However, when each layer to be laminated is formed thin in the capacitive sensor, there is a concern that a short circuit or breakage may occur due to the application of a strong external force. Further, when each layer to be laminated is formed thin in the capacitive sensor, there is a concern that when the insulating layer wears, the conductive layer is exposed and a short circuit occurs. Furthermore, when a stretchable material is used for the base material on which each layer is laminated in the capacitive sensor, it becomes difficult to form each layer to a uniform thickness, and there is a concern that a pair of conductive layers may short-circuit with each other.

[0006] The present invention takes the above problems as an example, and an object thereof is to provide a capacitive sensor capable of achieving both thinness and strength.

[0007] In order to achieve the above object, the capacitive sensor according to the present invention is a capacitive sensor including a first electrode body and a second electrode body, wherein the first electrode body and the second electrode body are formed in at least one linear shape on the same plane, and the first electrode body and the second electrode body are arranged in parallel with each other at a predetermined interval in a direction intersecting the expansion / contraction direction of the capacitive sensor.

[0008] In a capacitive sensor according to one aspect of the present invention, the first electrode body and the second electrode body may each be provided in multiple quantities, and the multiple first electrode bodies and second electrode bodies may be arranged in parallel and alternately at predetermined intervals.

[0009] In a capacitive sensor according to one aspect of the present invention, the first electrode body and the second electrode body may each have a wiring portion that allows one end to be connected to an external device.

[0010] In a capacitive sensor according to one aspect of the present invention, the thickness of the first electrode body and the second electrode body may be greater than the thickness of the wiring portion in the region where the first electrode body and the second electrode body face each other in the expansion and contraction direction on a plane.

[0011] The capacitive sensor according to the present invention makes it possible to achieve both thinness and strength.

[0012] This is a schematic plan view showing the configuration of a capacitive sensor according to an embodiment of the present invention. This is a plan view showing the capacitive sensor according to this embodiment in its normal state. This is a plan view showing the capacitive sensor according to this embodiment in its extended state. This is a graph showing an example of the relationship between elongation or bending angle and capacitance in the capacitive sensor according to this embodiment. This is a cross-sectional view of the first electrode body and the second electrode body and the fabric in the capacitive sensor according to this embodiment. This is a cross-sectional view of the wiring portion and the fabric in the capacitive sensor according to this embodiment. This is a graph showing an example of the relationship between elongation and capacitance in the capacitive sensor according to this embodiment and the capacitive sensor of the reference example. This is a plan view showing the process of manufacturing the lower layer of the insulating layer in the capacitive sensor according to this embodiment. This is a plan view showing the process of manufacturing the conductive layer in the capacitive sensor according to this embodiment. This is a plan view showing the process of reapplying the conductive layer to the capacitive portion in the capacitive sensor according to this embodiment. This is a plan view showing the process of manufacturing the upper layer of the insulating layer in the capacitive sensor according to this embodiment. This is a cross-sectional view of the capacitive sensor according to this embodiment. This is a schematic diagram showing an example of how the capacitive sensor according to this embodiment is used.

[0013] Hereinafter, a capacitive sensor according to an embodiment of the present invention will be described with reference to the drawings.

[0014] Figure 1 is a schematic plan view showing the configuration of a capacitive sensor according to an embodiment of the present invention.

[0015] In the following description, the horizontal (left-right) direction in the plan view of the capacitive sensor shown in Figure 1 is defined as the x-axis direction, and the direction perpendicular to the x-axis is defined as the y-axis direction. In addition, in the following description, the direction perpendicular to the x-axis and y-axis, that is, the direction that penetrates the drawing in the plan view shown in Figure 1, is defined as the z-axis direction (height direction, stacking direction). In the following description, the horizontal direction, vertical direction, left-right direction, up-down direction, etc., are based solely on the drawing in this embodiment and are not limited to the actual embodiment. In the following description, the direction of the xy plane, which is a plane perpendicular to the z-axis direction, is called the surface direction. In addition, in the following description, the surface shown in the plan view of Figure 1 is referred to as the front surface, and the surface opposite the front surface is referred to as the back surface.

[0016] As shown in Figure 1, the capacitive sensor 1 comprises a first electrode body 10 and a second electrode body 20. The first electrode body 10 and the second electrode body 20 are formed in at least one linear shape on the same plane and are arranged parallel to each other at a predetermined interval in a direction intersecting the expansion and contraction direction of the capacitive sensor 1, that is, the expansion and contraction direction of the object to be measured. The configuration and operation of the capacitive sensor 1 will be described in detail below.

[0017] [Configuration of Capacitive Sensor] The capacitive sensor 1 comprises the first electrode body 10, the second electrode body 20, and the wiring section 30 described above, as well as a fabric material 40 and a substrate module section 50. In Figure 1, the capacitive sensor 1 measures the expansion and contraction of the object to be measured in the x-axis direction, with the x-axis direction being the expansion and contraction direction. Here, the expansion and contraction direction is set to the direction in which the capacitive sensor 1 has high expandability, for example, it is set to the longitudinal direction of the capacitive sensor 1. The longitudinal direction of the sensor is the longitudinal direction in the region in which the first electrode body 10 and the second electrode body 20 are formed.

[0018] The fabric material 40 is, for example, a thin sheet made from fibers such as woven fabrics or nonwoven fabrics. The fabric material 40 has the property of being able to deform to conform to the surface shape of the object to be measured, for example, being soft and having little ability to maintain its shape. The fabric material 40 has an area on which the first electrode body 10, the second electrode body 20, the wiring section 30, and the substrate module section 50 can be placed. For example, the surface shape of the fabric material 40 is formed in a rectangular or substantially rectangular shape having a long side 41 and a short side 42, as shown in Figure 1. The surface shape of the fabric material 40 is not limited to the example described above.

[0019] The material of the fabric material 40 is not limited to the fibers described above, but can be any thin, sheet-like material that is deformable to conform to the surface shape of the object to be measured and that can form the first electrode body 10, the second electrode body 20, and the wiring portion 30. Furthermore, the capacitive sensor 1 does not need to have the fabric material 40. In other words, the capacitive sensor 1 may have the first electrode body 10 and the second electrode body 20 directly provided on the surface of the object to be measured.

[0020] The first electrode 10 and the second electrode 20 are both formed on a surface defined by the xy-plane, which is the same plane on the base material 40. The first electrode 10 and the second electrode 20 are formed in a linear shape, with the lengths (widths) W1 and W2 of the short sides 13 and 23 being shorter than the lengths L1 and L2 of the long sides 12 and 22 in the longitudinal direction. At least one of each, for example, five of each in Figure 1, are formed on the surface of the base material 40. Both the first electrode 10 and the second electrode 20 have an insulating layer made of an insulating elastomer composition on the outside of a conductive layer made of an elastomer composition containing a conductive material, for example. The specific configurations of the first electrode 10 and the second electrode 20 will be described later.

[0021] The first electrode body 10 and the second electrode body 20 are arranged parallel to each other at a predetermined distance apart such that their longitudinal directions intersect with the expansion and contraction direction of the object to be measured by the capacitive sensor 1 in the fabric material 40. The distance between the first electrode body 10 and the second electrode body 20 is such that a sufficient change in capacitance value occurs due to the change in the distance between the first electrode body 10 and the second electrode body 20 (inter-electrode distance) caused by expansion and contraction. The capacitive sensor 1 comprises at least one pair of first electrode body 10 and second electrode body 20. The direction in which the longitudinal directions of the first electrode body 10 and the second electrode body 20 are arranged, which intersects with the expansion and contraction direction, is not limited to the direction perpendicular to the x-axis direction as shown in Figure 1. For example, the direction intersecting with the expansion and contraction direction may be a direction having a predetermined angle with respect to the x-axis. Furthermore, the shapes of the first electrode body 10 and the second electrode body 20 are not limited to straight lines as shown in Figure 1, but may be, for example, wave-shaped or curved shapes with the direction intersecting with the expansion and contraction direction as the longitudinal direction.

[0022] In the capacitive sensor 1, there may be multiple sets of the first electrode body 10 and the second electrode body 20. The multiple sets of the first electrode body 10 and the second electrode body 20 may be arranged in parallel and alternately at predetermined intervals. For this reason, in the capacitive sensor 1, in the region enclosed by the dotted line in Figure 1, the first electrode body 10 and the second electrode body 20 are arranged in a comb-like manner in a region where they face each other in the direction of expansion and contraction on a plane. The comb-like arrangement of the first electrode body 10 and the second electrode body 20 is arranged so that their respective long sides 12 and 22 face each other. In the capacitive sensor 1, the region enclosed by the dotted line in Figure 1 forms the capacitive portion 60.

[0023] The first electrode 10 and the second electrode 20 function as a voltage application layer and a ground layer, respectively, depending on whether or not a voltage is applied. In this embodiment, the first electrode 10 is described as the voltage application layer and the second electrode 20 as the ground layer.

[0024] The wiring section 30 is electrically connected at one end to one end 11 of the first electrode body 10 or one end 21 of the second electrode body 20. The wiring section 30 connected to the first electrode body 10 is also called wiring section 30A, and the wiring section 30 connected to the second electrode body 20 is also called wiring section 30B. The other end of the wiring section 30 is provided with an electrode section that enables electrical connection between the capacitive sensor 1 and external equipment such as a substrate module section 50. The electrode section of the wiring section 30A connected to the first electrode body 10, which is the voltage application layer, is the positive electrode section 311. The electrode section of the wiring section 30B connected to the second electrode body 20, which is the ground layer, is the negative electrode section 312. The wiring section 30 is formed integrally with the first electrode body 10 and the second electrode body 20, for example, at a position closer to the long side 41 on the surface of the fabric material 40, so as not to hinder the flexibility of the fabric material 40. The length of the wiring section 30 can be appropriately determined according to the number of first electrode bodies 10 or second electrode bodies 20 connected, the length to the substrate module section 50, and so on.

[0025] The wiring section 30 allows one end 11, 21 of the first electrode body 10 and the second electrode body 20, respectively, to be connected to an external device in the capacitive sensor 1.

[0026] The wiring section 30A can electrically connect the first electrode body 10, made of a conductive resin material formed on the surface of the fabric material 40, to the substrate module section 50. Similarly, the wiring section 30B can electrically connect the second electrode body 20, made of a conductive resin material formed on the surface of the fabric material 40, to the substrate module section 50. The wiring section 30, like the first electrode body 10 and the second electrode body 20, is provided with an insulating layer made of an insulating elastomer composition on the outside of a conductive layer made of an elastomer composition containing a conductive material, for example. The specific configuration of the wiring section 30 will be described later.

[0027] The substrate module 50 includes an integrated circuit (IC), such as a microcontroller (MCU), which has I / O (input / output) ports 51 and a ground (GND) port 52, and a battery 53 that drives the control IC. The I / O port 51 is electrically connected to the positive electrode portion 311. The ground port 52 is electrically connected to the negative electrode portion 312. A switching circuit, such as a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), may be provided between the capacitive sensor 1 and the substrate module 50.

[0028] The connection method between the positive electrode portion 311 and the I / O port 51, and between the negative electrode portion 312 and the ground port 52, is not particularly limited and may be directly electrically connected or connected using a connector for thin substrates or the like.

[0029] Figure 2 is a plan view showing the capacitive sensor 1 in its normal state. Figure 3 is a plan view showing the capacitive sensor 1 in its extended state.

[0030] As shown in Figures 2 and 3, the capacitive sensor 1 is formed so that the first electrode body 10, the second electrode body 20, the wiring section 30, and the fabric material 40 can expand and contract in the x-axis direction, which is the direction of expansion and contraction of the object being measured. Specifically, in the expanded state shown in Figure 3, the first electrode body 10, which forms the voltage application layer, and the second electrode body 20, which forms the ground layer, expand and deform compared to the normal state (see Figure 2). In other words, the distance between the voltage application layer and the ground layer in the capacitance section 60 of the capacitive sensor 1 in the expansion direction (x-axis direction), i.e., the spacing, expands from l1 shown in Figure 2 to l2 shown in Figure 3. Therefore, the expansion of the object being measured can be measured by measuring the change in capacitance value between the normal state and the expanded state with the capacitive sensor 1.

[0031] Figure 4 is a graph showing an example of the relationship between elongation or bending angle and capacitance in a capacitive sensor 1.

[0032] As shown in Figure 4, the capacitance value of the capacitive sensor 1 changes when comparing a normal state S1 with an elongation of 0 millimeters and an elongated state S2 with a predetermined elongation, for example, 20 millimeters. Therefore, by using the capacitive sensor 1, the amount of elongation can be calculated from the change in capacitance value by deriving a relational expression from multiple elongation amounts and the capacitance values ​​at those elongation amounts.

[0033] Furthermore, the capacitive sensor 1 is not limited to linear elongation as shown in Figures 2 to 4. Even when bent together with the object being measured, the first electrode body 10 forming the voltage application layer and the second electrode body 20 forming the ground layer elongate and deform compared to the normal state. In other words, when the capacitive sensor 1 is bent, the distance between the voltage application layer and the ground layer in the elongation direction (x-axis direction) in the capacitance section 60 widens, and the capacitance value changes from the normal state. With the capacitive sensor 1, the bending angle of the object being measured can be measured by measuring this change in capacitance value.

[0034] In other words, as shown in Figure 4, the capacitance value of the capacitive sensor 1 changes when comparing the normal state with a bending angle of 0 degrees and a predetermined bending angle, for example, a 90-degree bending state. Therefore, by using the capacitive sensor 1, the bending angle can be calculated from the change in capacitance value by deriving a relational expression from multiple bending angles and the capacitance values ​​in each case.

[0035] In the case of the capacitive sensor 1, the graph in Figure 4 is merely an example, and the relationship between elongation and capacitance, or the relationship between bending angle and capacitance, is not limited to that shown in Figure 4.

[0036] Figure 5 is a cross-sectional view of the first electrode body 10 and the second electrode body 20 and the fabric material 40 in the capacitive sensor 1. Specifically, Figure 5 shows a cross-section in the stacking direction (z-axis direction) of the first electrode body 10 and the second electrode body 20 and the fabric material 40 in the region constituting the capacitance portion 60 of the capacitive sensor 1. Figure 6 is a cross-sectional view of the wiring portion 30 and the fabric material 40 in the capacitive sensor 1. Note that in Figures 5 and 6, only the conductive layers of the first electrode body 10, the second electrode body 20, and the wiring portion 30 are shown. In other words, the capacitive sensor 1 may have an insulating layer provided outside the conductive layers of the first electrode body 10, the second electrode body 20, and the wiring portion 30.

[0037] As shown in Figures 5 and 6, in the capacitive sensor 1, the thickness of the first electrode body 10 and the second electrode body 20 in the region constituting the capacitance portion 60 is formed to be greater than the thickness of the wiring portion 30. In the capacitive sensor 1, the thickness of the first electrode body 10 and the second electrode body 20 is set to N times the thickness of the wiring portion 30 (where N is an arbitrary value).

[0038] Figure 7 is a graph showing an example of the relationship between elongation and capacitance in the capacitive sensor 1 and the reference example capacitive sensor. In Figure 7, line C1 shows the change in elongation and capacitance in the capacitive sensor 1. Also in Figure 7, line C2 shows the change in elongation and capacitance in the reference example capacitive sensor. Unlike the capacitive sensor 1, the reference example capacitive sensor has a uniform thickness between the capacitance part and the wiring part. Furthermore, in Figure 7, the arrow nw indicates the capacitance generated in the wiring part in the capacitive sensor 1 and the reference example capacitive sensor. In the capacitive sensor 1 shown in Figure 7, the thickness of the first electrode body 10 and the second electrode body 20 are set to three times the thickness of the wiring part 30.

[0039] As shown in Figure 7, compared to the reference example's capacitive sensor, the degree of change in capacitance value with respect to elongation (slope of line C1) is larger in the capacitive sensor 1. Therefore, compared to the reference example's capacitive sensor, the degree of change in capacitance value with respect to elongation in the capacitive sensor 1 is sufficiently larger than the capacitance value of the wiring section indicated by arrow nw.

[0040] In the capacitance-type sensor 1, there is a concern that the capacitance generated in a portion other than the capacitance portion 60, which is the measurement site of the original elongation amount, for example, in the wiring portion 30 indicated by the arrow nw in FIG. 7, is added as a noise component to the capacitance of the plus-side electrode portion 311 and the minus-side electrode portion 312 and output.

[0041] Therefore, in the capacitance-type sensor 1, the thicknesses of the first electrode body 10 and the second electrode body 20 that function as the capacitance portion 60 are made N times the thickness of the wiring portion 30. By configuring in this way, in the capacitance-type sensor 1, the ratio of the capacitance portion 60 in the capacitance values output to the plus-side electrode portion 311 and the minus-side electrode portion 312 can be made dominant, so that a higher linearity of the change in capacitance value can be obtained.

[0042] [Layer arrangement and manufacturing process of capacitance-type sensor] Next, the arrangement and manufacturing process of each layer constituting the capacitance-type sensor 1 will be described.

[0043] FIG. 8 is a plan view showing the process of manufacturing the lower layer of the insulating layers 101 and 201 in the capacitance-type sensor 1. FIG. 9 is a plan view showing the process of manufacturing the conductive layers 102 and 202 in the capacitance-type sensor 1. FIG. 10 is a plan view showing the process of re-applying the conductive layers 103 and 203 to the capacitance portion 60 in the capacitance-type sensor 1. FIG. 11 is a plan view showing the process of manufacturing the upper layer of the insulating layers 104 and 204 in the capacitance-type sensor 1. FIG. 12 is a cross-sectional view of the capacitance-type sensor 1.

[0044] As shown in FIGS. 8 to 12, the capacitance-type sensor 1 can be manufactured, for example, by the following steps (1) to step (4). That is, the first electrode body 10 and the second electrode body 20 in the capacitance-type sensor 1 can be manufactured, for example, by the step (1) of manufacturing the lower insulating layers 101 and 201, the step (2) of applying an elastomer composition on the lower insulating layers 101 and 201 to manufacture the conductive layers 102 and 202, the step (3) of re-applying the conductive layers 103 and 203 to the capacitance portion 60, and the step (4) of manufacturing the upper insulating layers 104 and 204.

[0045] In the above process, the areas on the base material 40 where the first electrode body 10 and the second electrode body 20 will not be formed should be masked before each layer is manufactured. Also, in step (3), in order to reapply (overcoat, thicken) the conductive layers 103 and 203 only to the capacitance portion 60 in accordance with the difference in the thickness of the conductive layers between the wiring portion 30 and the capacitance portion 60, the wiring portion 30 should be masked in addition to the areas where the first electrode body 10 and the second electrode body 20 will not be formed before the conductive layer is manufactured. Each layer can be manufactured by an appropriate method such as spray coating, screen printing, or inkjet printing.

[0046] As shown in Figure 12, the lower insulating layers 101 and 201 are formed on the surface of the fabric material 40 closest to the surface of the object to be measured, covering the outside of the conductive layers 102, 202, 103, and 203 in the first electrode body 10 and the second electrode body 20. The upper insulating layers 104 and 204 are formed on the topmost (surface) layer of the capacitive sensor 1, furthest from the surface of the object to be measured, covering the outside of the conductive layers 102, 202, 103, and 203 in the first electrode body 10 and the second electrode body 20. The insulating layers 101, 201, 104, and 204 are provided to cover the upper and lower sides of the conductive layers 102, 202, 103, and 203, as well as the left and right sides of the conductive layers 102, 202, 103, and 203.

[0047] Furthermore, among the insulating layers 101, 201, 104, and 204, the portions that cover the left-right sides of the conductive layers 102, 202, 103, and 203 may be formed together with the lower insulating layers 101 and 201, or together with the upper insulating layers 104 and 204. Also, among the insulating layers 101, 201, 104, and 204, the portions that cover the left-right sides of the conductive layers 102, 202, 103, and 203 may include both portions formed together with the lower insulating layers 101 and 201 and portions formed together with the upper insulating layers 104 and 204.

[0048] The first insulating layers 101 and 201 and the second insulating layers 104 and 204 are made of an elastomer composition having a relatively high dielectric constant, for example, 3 or more (measurement frequency: 100 Hz). Examples of the elastomer composition include those containing an elastomer and, if necessary, other optional components such as dielectric particles. Examples of the elastomer include natural rubber, isoprene rubber, nitrile rubber (NBR), ethylene propylene rubber (EPDM), styrene butadiene rubber (SBR), butadiene rubber (BR), chloroprene rubber (CR), silicone rubber, fluorine rubber, acrylic rubber, hydrogenated nitrile rubber, urethane rubber, and the like. These may be used alone or in combination of two or more kinds.

[0049] The conductive layers 102, 202, 103, and 203 are formed inside (center side) of the insulating layers 101, 201, 104, and 204 in the first electrode body 10 and the second electrode body 20 (see FIG. 12). The conductive layers 102 and 103 constitute the conductive layer, that is, the voltage application layer, in the first electrode body 10. Specifically, in the first electrode body 10, the location where the conductive layer 102 and the conductive layer 103 are formed constitutes the capacitance portion 60. In addition, in the first electrode body 10, the location where only the conductive layer 102 is formed constitutes the wiring portion 30. The conductive layers 202 and 203 constitute the conductive layer, that is, the ground layer, in the second electrode body 20. Specifically, in the second electrode body 20, the location where the conductive layer 202 and the conductive layer 203 are formed constitutes the capacitance portion 60. In addition, in the second electrode body 20, the location where only the conductive layer 202 is formed constitutes the wiring portion 30.

[0050] As described above, on the conductive layers 102 and 202 of the capacitance portion 60, the conductive layers 103 and 203 are recoated and formed thicker than the conductive layers 102 and 202 of the wiring portion 30. However, in the capacitive sensor 1, the method of providing a difference in thickness between the capacitance portion 60 and the wiring portion 30 is not limited to this. For example, the conductive layers of the capacitance portion 60 and the wiring portion 30 may be separately masked and applied with different thicknesses.

[0051] The conductive layers 102, 202, 103, and 203 are composed of, for example, an elastomer composition containing conductive materials such as carbon black, carbon nanotubes, silver nanoparticles, and other conductive particles.

[0052] Figure 13 is a schematic diagram showing an example of how the capacitive sensor 1 is used. As shown in Figure 13, the capacitive sensor 1 can detect the movement of living organisms such as humans by being attached to a supporter 400 worn on the user's arm or leg, or to fabric such as clothing. In a supporter 400 worn on the arm, the capacitive sensor 1L attached at the wrist can measure the bending motion of the wrist joint. In a supporter 400 worn on the arm, the capacitive sensor 1T attached at the surface of the arm can measure the twisting motion of the arm muscles. In a supporter 400 worn on the arm, the capacitive sensor 1E attached at the elbow can measure the bending motion of the elbow joint.

[0053] In the supporter 400, the capacitive sensors 1L, 1E, and 1T are electrically connected to a single substrate module 500. In the capacitive sensor 1, the substrate module 50 is not limited to having one for each of the first electrode body 10 and the second electrode body 20, as shown in Figure 1, but may also be configured such that multiple first electrode bodies 10 and second electrode bodies 20 are connected to a single substrate module 50, as shown in Figure 13. The first electrode bodies 10 and the second electrode bodies 20 and the substrate module 50 are connected to the substrate module 50 by a wiring section 300 made of conductive resin, similar to the wiring section 30. The wiring section 300 may be a regular cable. In addition to a microcontroller and a battery, the substrate module 50 has a communication function that transmits data measured by the capacitive sensors 1L, 1E, and 1T to external devices wirelessly or via a wired connection.

[0054] [Effects of Capacitive Sensors] As explained above, the capacitive sensor 1 can provide the following effects.

[0055] In the capacitive sensor 1, the first electrode body 10 and the second electrode body 20 are formed in at least one linear shape on the same plane, for example, on the surface of a fabric material 40, and are arranged parallel to each other at a predetermined distance in a direction intersecting the expansion and contraction direction of the capacitive sensor 1. The portions of the first electrode body 10 and the second electrode body 20 that face each other on the plane constitute a capacitance portion 60. Therefore, in the operating state where the capacitive sensor 1 is attached to the surface of an object to be measured, the distance between the first electrode body 10, which acts as a voltage application layer, and the second electrode body 20, which acts as a ground layer, changes as the object to be measured expands and contracts, causing a change in the capacitance value. Accordingly, the capacitive sensor 1 can measure deformations such as the amount of elongation and bending angle of the object to be measured based on the change in capacitance value.

[0056] By arranging the first electrode body 10 and the second electrode body 20 in the planar direction, the capacitive sensor 1 can be made thinner in the height direction compared to the structure of a conventional capacitive sensor in which an insulating layer and a pair of conductive layers serving as a voltage application layer and a ground layer are laminated. Therefore, the capacitive sensor 1 can reduce the risk of short circuits or breakage caused by external forces.

[0057] In the capacitive sensor 1, multiple first electrode bodies 10 and second electrode bodies 20 may be provided, and they may be arranged in parallel and alternately at predetermined intervals. With this configuration, the capacitive sensor 1 can measure deformations such as the amount of elongation and bending angle of an object being measured with greater sensitivity and precision, based on changes in capacitance values ​​accompanying the expansion and contraction of the object being measured, using multiple sets of first electrode bodies 10 and second electrode bodies 20 during use.

[0058] In the capacitive sensor 1, the first electrode body 10 and the second electrode body 20 may each have a wiring section 30 that allows one end 11, 21 of each to be connected to an external device. With this configuration, the capacitive sensor 1 can be easily connected to a substrate module section 50 or an external device at one end 11, 21 of each of the first electrode body 10 and the second electrode body 20.

[0059] In the capacitive sensor 1, the thickness of the first electrode body 10 and the second electrode body 20 may be greater than the thickness of the wiring portion 30 in the region where the first electrode body 10 and the second electrode body 20 face each other in the direction of expansion and contraction on a plane, that is, in the region constituting the capacitance portion 60. By configuring it in this way, the capacitive sensor 1 can reduce the proportion of the wiring portion 30 in the capacitance value output to the positive electrode portion 311 and the negative electrode portion 312, making the proportion of the capacitance portion 60 dominant. This allows for higher linearity of the change in capacitance value, enabling more sensitive and precise measurement of deformations such as the amount of elongation and bending angle of the object being measured.

[0060] Furthermore, those skilled in the art may modify the present invention as appropriate in accordance with prior art knowledge. Such modifications, insofar as they still possess the configuration of the present invention, are of course included within the scope of the present invention.

[0061] For example, in the capacitive sensor 1 described above, the object to be measured is not limited to living organisms such as the human body, but can measure the elongation and bending angle of various objects.

[0062] For example, the capacitive sensor 1 described above may use a supporter 400 or clothing fabric as the fabric material 40, and form the first electrode body 10 and the second electrode body 20 on it.

[0063] For example, the capacitive sensor 1 described above may have a dielectric layer made of a dielectric material in the region where the first electrode body 10 and the second electrode body 20 face each other on a plane. By having a dielectric layer, the initial value of the capacitance of the capacitive sensor 1 becomes higher, and the change in capacitance in response to expansion and contraction becomes larger, thus further improving the accuracy.

[0064] 1, 1E, 1L, 1T... Capacitive sensor, 10... First electrode body, 11... One end, 12... Long side, 13... Short side, 20... Second electrode body, 21... One end, 22... Long side, 23... Short side, 30, 30A, 30B, 300... Wiring section, 40... Fabric material, 41... Long side, 42... Short side, 50, 500... Circuit board module section, 51... I / O (Input / Output) port, 52... Ground (GND) port, 53... Battery, 60... Capacitive section, 101, 201... Insulating layer (first insulating layer), 102, 202, 103, 203... Conductive layer, 104, 204... Insulating layer (second insulating layer), 311... Positive side electrode section, 312... Negative side electrode section, 400... Supporter

Claims

1. A capacitive sensor comprising a first electrode body and a second electrode body, wherein the first electrode body and the second electrode body are formed in at least one linear shape on the same plane, and the first electrode body and the second electrode body are arranged parallel to each other at a predetermined distance in a direction intersecting the expansion and contraction direction of the capacitive sensor.

2. The capacitive sensor according to claim 1, wherein a plurality of first electrode bodies and second electrode bodies are provided, and the plurality of first electrode bodies and second electrode bodies are arranged in parallel and alternately at predetermined intervals.

3. The capacitive sensor according to claim 1 or 2, wherein the first electrode body and the second electrode body each have a wiring portion that allows one end to be connected to an external device.

4. The capacitive sensor according to claim 3, wherein the thickness of the first electrode body and the second electrode body is greater than the thickness of the wiring portion in the region where the first electrode body and the second electrode body face each other in the expansion and contraction direction on a plane.

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