Capacitance detection device capable of calculating shear force

Abstract

The present invention provides a capacitance detection device capable of calculating shear force, which is formed with a first electrode, an insulating layer is formed on the first electrode, and a second electrode is formed on the insulating layer, and the capacitance detection device can calculate the shear force applied from the upper part of the second electrode. The capacitance detection device can solve the problem of difficulty in measuring high-precision pressure distribution in previous capacitance-type detection devices. Furthermore, it is possible to detect stress in the surface direction (X, Y direction) parallel to the plane, i.e., shear force. By improving the material and structure of the above-mentioned insulating layer, or improving the pattern of the above-mentioned first electrode and the second electrode, or making the first electrode pass through an independent AC drive circuit, the shear force can be measured with higher accuracy. By providing a temperature sensor, temperature-based correction can be performed, and by setting it so that there is no frame portion in any of the two directions orthogonal to the periphery of the sensing portion of the electrode, it is possible to achieve elongation.

Description

[0001] This application is a divisional application of the invention patent application with application number 201980061868.3, application date September 18, 2019, and invention name “Capacitance detection device capable of calculating shear force”. Technical Field

[0002] The present invention relates to a capacitance detection device used in a device for measuring the ground contact state of a tire, a shoe sole, a track point, etc. Background Art

[0003] Conventionally, as a method for measuring the ground contact state of a tire, the invention disclosed in the following Patent Document 1 is known. The invention is an invention having the following structure: a substrate having a surface for making the tire ground contact, a capacitance detection device disposed on the surface of the substrate and having a plurality of pressure measurement points, and a protective sheet covering the surface of the capacitance detection device, wherein the capacitance detection device is filled between a first linear electrode and a second linear electrode with a resin whose resistance decreases according to the amount of deformation when compressed.

[0004] Furthermore, the resistance of the resin decreases as the force pressing the outer surface of the sheet increases. Therefore, at the intersection of the first linear electrode and the second linear electrode when viewed from above, the resistance of the first linear electrode and the second linear electrode decreases by pressing the sheet. Therefore, by measuring the above resistance, the force acting on the resin at the intersection can be measured, and the contact surface shape and contact pressure distribution of the tire can be obtained.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2018-72041 Summary of the invention

[0008] Problems to be solved by the invention

[0009] However, of the forces acting on the resin at the above-mentioned intersection, only the component in the Z-axis direction (the direction perpendicular to the linear electrode) can be detected, and the component in the XY-axis direction (the direction of tire movement is set as the X-axis, and the direction perpendicular to it is set as the Y-axis) cannot be detected. That is, in a capacitance detection device with such a structure, only the ground contact pressure distribution in the Z-axis direction can be obtained. For example, the ground contact pressure distribution of the stress in the XY-axis direction (hereinafter referred to as "shear force") applied from an oblique direction due to the tire contacting the ground cannot be measured. Therefore, the true ground contact state between the tire and the ground contact surface cannot be measured, and there is a problem that it is insufficient as a test device for measuring tire performance, etc.

[0010] The present invention is proposed in view of the actual situation as mentioned above, and is an invention related to the following capacitance detection device, which is a device that can not only calculate the stress of the component in the Z-axis direction, but also calculate the shear force applied in the oblique direction from the upper part of the second electrode. The principle is that the second electrode is deformed or moved laterally according to the magnitude of the above-mentioned shear force, and the change in the capacitance value generated between the deformed or laterally moved second electrode and the first electrode is detected, and the original shear force is calculated according to the magnitude of the change in the capacitance value. It can be used in a device for measuring the true grounding state of tires, soles, pointing sticks, etc.

[0011] Methods for solving problems

[0012] That is, the first embodiment of the present invention is a capacitance detection device, which has a first electrode, an insulating layer formed on the first electrode, and a second electrode formed on the insulating layer, and the capacitance detection device can calculate the shear force applied from the upper part of the second electrode.

[0013] In addition, a second embodiment of the present invention is a capacitance detection device, characterized in that the insulating layer is composed of multiple layers having different physical or chemical properties. In addition, a third embodiment of the present invention is a capacitance detection device, characterized in that the insulating layer has layers. In addition, a fourth embodiment of the present invention is a capacitance detection device, characterized in that the Poisson's ratio of the insulating layer is 0 to 0.48.

[0014] In addition, the fifth embodiment of the present invention is a capacitance detection device, characterized in that the first electrode and the second electrode are composed of linear patterns, which are patterns extending in the same direction when viewed from above. In addition, the sixth embodiment of the present invention is a capacitance detection device, characterized in that the first electrode is composed of an island pattern, the second electrode is composed of two layers of an upper second electrode and a lower second electrode, and the upper second electrode and the lower second electrode are composed of a plurality of linear patterns that cross when viewed from above, and a portion of the island pattern of the first electrode overlaps with a portion of the pattern of the upper second electrode and a portion of the pattern of the lower second electrode when viewed from above. In addition, the seventh embodiment of the present invention is a capacitance detection device, characterized in that the area where a portion of the island pattern of the first electrode overlaps with a portion of the pattern of the upper second electrode when viewed from above is larger than the area where a portion of the island pattern of the first electrode overlaps with a portion of the pattern of the lower second electrode when viewed from above.

[0015] In addition, the eighth embodiment of the present invention is a capacitance detection device, wherein the first electrode is connected to the processing unit via an independent AC drive circuit, and the second electrode is connected to the processing unit via a signal conversion unit. In addition, the ninth embodiment of the present invention is a capacitance detection device, characterized in that a temperature sensor is provided on any of the above layers, and the temperature sensor is used to measure the heat generated by the pressing body applied from the above second electrode. In addition, the tenth embodiment of the present invention is a capacitance detection device, characterized in that there is no frame portion in any of the two directions orthogonal to the sensing portion of the first electrode or the second electrode.

[0016] Effects of the Invention

[0017] The capacitance detection device of the present invention is a capacitance detection device having a first electrode, an insulating layer formed on the first electrode, and a second electrode formed on the insulating layer, and is characterized in that the shear force applied from the upper part of the second electrode can be calculated. Therefore, not only the distribution of the grounding pressure in the Z-axis direction can be measured, but also the distribution of the grounding pressure of the shear force applied from the oblique direction can be measured, and thus, the following effects can be achieved: the true grounding state between the grounded body such as the tire and the sole and the grounding surface can be measured, and the true performance of the grounded body can be measured.

[0018] In addition, the capacitance detection device of the present invention is characterized in that the above-mentioned insulating layer is composed of multiple layers having different physical or chemical properties. In addition, the capacitance detection device of the present invention is characterized in that the above-mentioned insulating layer has layers. Therefore, it has the effect of being able to accurately measure the measured value of the shear force and improve the durability of the insulating layer. In addition, the capacitance detection device of the present invention is characterized in that the Poisson's ratio of the above-mentioned insulating layer is 0 to 0.48. Therefore, it has the following effects: it is possible to reduce the noise at the edge of the stress contact point caused by the deflection of the shear force, it is easy to distinguish the detection of the pressure in the Z-axis direction and the detection of the shear force in the XY-axis direction, and the accuracy of the detection data is improved.

[0019] In addition, the capacitance detection device of the present invention is characterized in that the first electrode and the second electrode are composed of linear patterns, which are patterns extending in the same direction when viewed from above. Therefore, if a shear force is applied from a direction that intersects with a direction in which the linear pattern of the second electrode extends, the second electrode is deformed according to the magnitude of the shear force, and the distance between the second electrode and the first electrode changes. As the distance between the second electrode and the first electrode changes, the capacitance value between the second electrode and the first electrode changes, so that the magnitude of the shear force can be detected by detecting the electrical signal.

[0020] In addition, the capacitance detection device of the present invention is characterized in that the first electrode is composed of an island pattern, the second electrode is composed of two layers of an upper second electrode and a lower second electrode, and the upper second electrode and the lower second electrode are composed of a plurality of linear patterns that cross when viewed from above, and a portion of the island pattern of the first electrode overlaps with a portion of the pattern of the upper second electrode and a portion of the pattern of the lower second electrode when viewed from above. Therefore, if a shear force is applied from a direction that intersects with the direction of either the upper second electrode or the lower second electrode of the second electrode, the upper second electrode or the lower second electrode of the second electrode deforms or moves according to the magnitude of the shear force, and the distance between the second electrode and the first electrode changes. As the distance between the second electrode and the first electrode changes, the capacitance value between the upper second electrode or the lower second electrode of the second electrode and the first electrode changes, so that the magnitude of the shear force in each direction (the magnitude of the component force in the X-axis direction of the shear force and the magnitude of the component force in the Y-axis direction) can be detected separately by detecting the electrical signal.

[0021] In addition, the capacitance detection device of the present invention is characterized in that the area where a part of the island pattern of the first electrode overlaps with a part of the pattern of the upper second electrode when viewed from above is larger than the area where a part of the island pattern of the first electrode overlaps with a part of the pattern of the lower second electrode when viewed from above. Therefore, although the detection sensitivity of the capacitance value between the first electrodes formed by the island pattern is generally lower in the upper second electrode than in the lower second electrode, the detection sensitivity can be corrected to be approximately the same. As a result, it has the effect of being able to measure the shear force applied to the upper part of the second electrode without deviation in the X direction and the Y direction.

[0022] In addition, the capacitance detection device of the present invention is characterized in that the first electrode is connected to the processing unit via an independent AC drive circuit, and the second electrode is connected to the processing unit via a signal conversion unit. Therefore, each first electrode of a complex and fine pattern is electrically connected to the processing unit via an independent AC drive circuit of a similarly complex and fine pattern, so that the capacitance value can be detected in each very fine range, and a very high-precision measurement can be performed.

[0023] In addition, the capacitance detection device of the present invention is characterized in that a temperature sensor is provided in any of the above layers, and the temperature sensor is used to measure the heat generated by the above shear force. Therefore, it has the following effect: the error caused by the temperature dependence of the distribution of the measured shear force can be corrected by the above temperature sensor, and the true distribution of the shear force can be calculated. In addition, since the amount of energy loss caused by heat can be estimated, the state of the ground contact surface with less loss can be measured, which has the effect of promoting the development of products with good energy efficiency.

[0024] In addition, the capacitance detection device of the present invention is characterized in that there is no frame portion in any of the two directions orthogonal to the sensing portion of the first electrode or the second electrode. Therefore, if a plurality of the capacitance detection devices are arranged and joined to form a long strip, the shear force measurement range in the long strip direction can be infinitely extended.

[0025] In addition, the capacitance detection device of the present invention is characterized in that the substrate or insulating layer on which the above-mentioned first electrode or second electrode is formed, or the protective layer protecting them is removable. Therefore, even in the case where the protective layer on the surface is worn, the measurement can be continued only by replacing the protective layer. In addition, even in the case where the electrode is damaged and becomes unusable, the measurement can be continued only by replacing the substrate on which the electrode is formed. Therefore, there is no need to purchase new other capacitance detection devices, which has the effect of greatly reducing costs. In addition, since the period during which a capacitance detection device can continue to be used becomes longer, the error of the measurement value caused by the deviation between the various products of the capacitance detection device is reduced, and as a result, the accuracy of the measurement value itself is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] [ Figure 1 ] is a cross-sectional view of the entire capacitance detection device of one embodiment of the present invention.

[0027] [ Figure 2 ] is a cross-sectional view showing an embodiment in which a shear force is applied obliquely from the upper part of a main detection part of a capacitance detection device of one embodiment of the present invention, causing a part of the main detection part of the capacitance detection device to be deformed.

[0028] [ Figure 3 ] is a cross-sectional view showing an embodiment in which two insulating layers are stacked in the insulating layer of a capacitance detection device according to an embodiment of the present invention.

[0029] [ Figure 4 ] is a cross-sectional view showing an embodiment in which, in an insulating layer of a capacitance detection device according to an embodiment of the present invention, the insulating layer is composed of a plurality of foam layers and the insulating layer is layered.

[0030] [ Figure 5 ] is a cross-sectional view showing an embodiment in which, in an insulating layer of a capacitance detection device according to an embodiment of the present invention, a layer is given to the insulating layer by forming countersunk protrusions and depressions in the insulating layer.

[0031] [ Figure 6 ] is a schematic diagram showing an embodiment in which, in a first electrode and a second electrode of a capacitance detection device of an embodiment of the present invention, patterns of the first electrode and the second electrode are linear patterns extending in the same direction when viewed from above.

[0032] [ Figure 7 ] is a detailed diagram showing an embodiment in which, in the first electrode and the second electrode of a capacitance detection device of an embodiment of the present invention, the patterns of the first electrode and the second electrode are linear patterns extending in the same direction when viewed from above, and is a detailed diagram showing a case in which the first electrode has three linear patterns and the second electrode has two linear patterns.

[0033] [ Figure 8 ] are schematic top views showing special examples of linear patterns of the first electrode and the second electrode in the first electrode and the second electrode of the capacitance detection device of one embodiment of the present invention, (a) is a schematic top view showing the first electrode and the second electrode as linear patterns with different widths and lengths, respectively, (b) is a schematic top view showing the first electrode and the second electrode as having widths that are locally widened or narrowed, (c) is a schematic top view showing the first electrode and the second electrode as polygonal shapes or arc-shaped shapes, and (d) is a schematic top view showing the first electrode and the second electrode as a composite shape or a wavy shape.

[0034] [ Figure 9-1 ] is a cross-sectional view showing a capacitance detection device in which the first electrode and the second electrode of the capacitance detection device according to one embodiment of the present invention are respectively composed of two layers.

[0035] [ Figure 9-2 ] is a case where the first electrode and the second electrode of the capacitance detection device of one embodiment of the present invention are respectively composed of two layers, (a) is a top view showing the pattern of each layer of the second electrode, and (b) is a top view showing the pattern of each layer of the first electrode.

[0036] [ Fig.10 ] is a schematic diagram showing an example in which a plurality of capacitance detection devices according to an embodiment of the present invention are arranged in a vertical and horizontal matrix to form a capacitance detection device group.

[0037] [ Fig.11 ] is a schematic diagram showing an example in which a plurality of capacitance detection devices according to an embodiment of the present invention, each of which has multiple layers of second electrodes and first electrodes, are arranged in a vertical and horizontal matrix to form a capacitance detection device group.

[0038] [ Figure 12-1 ] is a cross-sectional view of a capacitance detection device in one embodiment of the present invention, in which the first electrode of the capacitance detection device is composed of a rectangular island pattern, the second electrode is two layers of an upper second electrode and a lower second electrode, and they are composed of a plurality of intersecting linear patterns.

[0039] [ Figure 12-2] is a top view of the patterns of the upper second electrode and the lower second electrode of the second electrode when the first electrode of a capacitance detection device in one embodiment of the present invention is composed of a rectangular island pattern, and the second electrode is two layers of an upper second electrode and a lower second electrode, and they are composed of a plurality of intersecting linear patterns.

[0040] [ Figure 12-3 ] is a top view showing the pattern and positional relationship of the first electrode and the upper second electrode and the lower second electrode of the second electrode when the first electrode of the capacitance detection device of one embodiment of the present invention is composed of a rectangular island pattern, and the second electrode is composed of two layers of an upper second electrode and a lower second electrode, and they are composed of a plurality of intersecting linear patterns.

[0041] [ Figure 12-4 ] is a top view of the area where the patterns of the upper second electrode and the lower second electrode of the first electrode and the second electrode overlap when the first electrode of the capacitance detection device in one embodiment of the present invention is composed of a rectangular island pattern, and the second electrode is composed of two layers of an upper second electrode and a lower second electrode, and they are composed of a plurality of intersecting linear patterns.

[0042] [ Figure 12-5 ] is a top view showing a state in which the overlapping area of ​​the pattern of the upper second electrode of the first electrode and the second electrode changes due to shear force when the first electrode and the second electrode of the capacitance detection device in one embodiment of the present invention are formed by a rectangular island pattern, and the second electrode is composed of two layers of an upper second electrode and a lower second electrode, and they are formed by a plurality of intersecting linear patterns.

[0043] [ Figure 12-6 ] is a top view showing a state in which the overlapping area of ​​the pattern of the lower second electrode of the first electrode and the second electrode changes due to shear force when the first electrode and the second electrode are subjected to a shear force, when the first electrode of the capacitance detection device in one embodiment of the present invention is composed of a rectangular island pattern, and the second electrode is composed of two layers of an upper second electrode and a lower second electrode and is composed of a plurality of linear patterns intersecting these layers.

[0044] [ Fig.13 ] is a top view showing a capacitance detection device of an embodiment of the present invention in which the first electrode is composed of a parallelogram-shaped island pattern, and the second electrode is two layers of an upper second electrode and a lower second electrode, which are composed of a plurality of intersecting linear patterns.

[0045] [ Fig.14 ] is a top view showing a capacitance detection device of an embodiment of the present invention, in which the first electrode is composed of an island pattern in which the four corners of a rectangle are rounded and there are no four vertices, and the second electrode is a two-layer upper second electrode and a lower second electrode, which are composed of a plurality of intersecting linear patterns.

[0046] [ Figure 15-1 ] is a top view showing a capacitance detection device of an embodiment of the present invention in which the first electrode is composed of a vertically long elliptical island pattern, and the second electrode is two layers of an upper second electrode and a lower second electrode, which are composed of a plurality of intersecting linear patterns.

[0047] [ Figure 15-2 ] is a top view showing a state in which the first electrode of a capacitance detection device of an embodiment of the present invention is composed of a vertically long elliptical island pattern, and the overlapping area of ​​the pattern of the first electrode and the upper part of the second electrode changes due to shear force.

[0048] [ Fig.16 ] is a schematic diagram showing an example of connection wiring of each electrode of the first electrode, each independent AC drive circuit and the drive circuit, in a case where the first electrode is connected to the processing unit via an independent AC drive circuit and the second electrode is connected to the processing unit via a signal conversion unit in a first electrode and a second electrode of a capacitance detection device of an embodiment of the present invention.

[0049] [ Fig.17 ] is a schematic diagram showing a configuration schematic diagram when an independent AC drive circuit is formed by a logic circuit and a signal example during operation, in a first electrode and a second electrode of a capacitance detection device of an embodiment of the present invention, when the first electrode is connected to a processing unit via an independent AC drive circuit and the second electrode is connected to the processing unit via a signal conversion unit.

[0050] [ Fig.18 ] is a schematic diagram showing a signal example of nine signal lines when an AC signal is independently output to three of the first electrodes, in a first electrode and a second electrode of a capacitance detection device of an embodiment of the present invention, when the first electrode is connected to a processing unit via an independent AC drive circuit and the second electrode is connected to the processing unit via a signal conversion unit.

[0051] [ Fig.19 ] is a schematic diagram showing an example in which a temperature sensor is provided in a capacitance detection device according to one embodiment of the present invention.

[0052] [ Fig. 20 ] is a schematic diagram showing an example in which a temperature detection electrode is provided near a first electrode and a second electrode in a capacitance detection device according to an embodiment of the present invention.

[0053] [ Fig.21] is a schematic top view showing an example in which, in a capacitance detection device according to one embodiment of the present invention, the positions of the first electrode and the second electrode and the position of the detour wiring are slightly offset and patterned in parallel, thereby eliminating the presence of a border portion in either of two directions orthogonal to the sensing portion of the first electrode and the second electrode.

[0054] [ Fig. 22 ] is a schematic top view showing an example in which, when a plurality of capacitance detection devices according to an embodiment of the present invention are arranged in a vertical row and joined, in order to prevent each capacitance detection device from moving and shifting, a portion of the capacitance detection device is provided with a protrusion and a recess that form a key-to-keyhole relationship.

[0055] [ Fig.23 ] is a schematic cross-sectional view showing an example in which a portion of a protective layer is to be removed in a capacitance detection device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0056] Hereinafter, an embodiment of the present invention will be described based on the accompanying drawings. The capacitance detection device 1 of the present invention is a capacitance detection device as follows: a first electrode 20 is formed on a substrate 10, an insulating layer 30 is formed on the first electrode 20, and a second electrode 40 is formed on the insulating layer 30, and a shear force 60 applied from an oblique direction on the second electrode 40 can be calculated. Furthermore, the capacitance detection device 1 may also have a structure in which a protective layer 50 is formed on the upper part of the second electrode 40, and a shear force 60 is applied from the protective layer 50. Moreover, the first electrode 20 and the second electrode 40 of the capacitance detection device 1 are structures electrically connected to the processing unit 120 via different electrical wirings, respectively, and are configured to be able to detect changes in the capacitance value generated between the first electrode 20 and the second electrode 40 through the processing unit 120 (refer to Figure 1 ).

[0057] If a shear force 60 is applied in an oblique direction from the second electrode 40 of the capacitance detection device 1 or the protective layer 50, the second electrode 40, which is the main detection part of the capacitance detection device 1, is deformed or moved according to the strength of the shear force 60, and the capacitance value generated between the first electrode 20 and the second electrode 40 changes. This is a structure that can calculate the strength of the applied shear force 60 based on the change in the capacitance value. For example, in the case where the first electrode 20 includes an electrode 25 and an electrode 26 composed of a plurality of linear patterns, and the second electrode 40 includes an electrode 41 and an electrode 42 composed of a plurality of linear patterns, when a shear force 60 is applied from the oblique upper direction of the second electrode 40, according to the strength of the shear force 60, one of the electrodes 41 in the second electrode 40 is deformed or moved by the applied shear force 60, and not only one of the electrodes 21 in the first electrode 20 located directly obliquely below it, but also the distance between the electrode 21 and the adjacent electrode 22 changes. Therefore, by measuring the change in the capacitance value between the electrode 41 and the electrode 21 and the change in the capacitance value between the electrode 41 and the electrode 22, the strength of the shear force 60 in the oblique direction can be measured (see Figure 2 ).

[0058] Next, the insulating layer 30 is described. The insulating layer 30 is preferably composed of multiple layers having different physical properties or chemical properties. Physical properties refer to the inherent properties of the material such as density, hardness, specific gravity, melting point, boiling point, specific heat capacity, dielectric constant, magnetic permeability, magnetic susceptibility, electrical conductivity, refractive index, odor, color, elastic modulus, shear strength, tensile failure nominal strain, tensile strength, impact resistance, wear resistance, compression rate, compression strength, bending strength, yield stress, tensile strength, etc., which have properties with respect to external force loads. In addition, chemical properties refer to the properties of a new substance that is to be transformed into a substance with different properties by reacting with other substances in the presence of other substances.

[0059] Taking elastic modulus as an example, if the insulating layer 30 is formed into a two-layer structure in which an insulating layer 32 with a low elastic modulus is stacked on an insulating layer 31 with a high elastic modulus (see Figure 3 ), the following effects are achieved: in the insulating layer 32 having a low elastic modulus, the insulating layer is deformed with good sensitivity in accordance with the deflection of the applied shear force, and in the insulating layer 31 having a high elastic modulus, its excessive deformation is suppressed, thereby protecting the first electrode 20 located therebelow from damage or degradation. In addition, since the offset that is the cause of the error in the measured value of the shear force 60 in the oblique direction is reduced, the measured value of the shear force 60 can be accurately measured. Furthermore, if the measurement accuracy is improved, the sampling speed is also increased as a result.

[0060] The elastic modulus mentioned in the present invention refers to the value obtained by cutting the insulating layer 31 and the insulating layer 32 into the shape of a dumbbell No. 1 test piece, using a non-contact elongation width meter capable of measuring a small displacement, and using the tensile test method based on JIS K7127 and JIS K7161, dividing the tensile stress applied to the insulating layer 31 and the insulating layer 32 by the strain generated in the insulating layer 31 and the insulating layer 32. The insulating layer 30 composed of multiple layers can be not only the two layers shown above, but also a layer formed with more than three layers. In addition, the elastic modulus of each layer of the above-mentioned insulating layer 30 is a relative comparison, which only indicates that the elastic modulus of the insulating layer 32 is lower than the elastic modulus of the insulating layer 31, and does not indicate the absolute value of the elastic modulus of each layer.

[0061] That is, in the case where the insulating layer is composed of two layers stacked together, for example, the elastic modulus of the insulating layer 31 may be 2 GPa, and the elastic modulus of the insulating layer 32 may be 1 GPa. Alternatively, the elastic modulus of the insulating layer 31 may be 0.3 GPa, and the elastic modulus of the insulating layer 32 may be 0.01 GPa. The ratio of the elastic modulus of the insulating layer 31 / the elastic modulus of the insulating layer 32 may be set in the range of 1.1 to 200. If the ratio of the elastic modulus of the insulating layer 31 / the elastic modulus of the insulating layer 32 is less than 1.1, the deformation caused by the shear force 60 passes through the insulating layer 30 and reaches the first electrode 20, and the first electrode 20 is easily degraded or damaged. On the other hand, if it exceeds 200, the following problem occurs: the deformation caused by the shear force 60 is absorbed only by the insulating layer 32, and the mechanical strength is reduced due to its cumulative load, and the durability of the insulating layer 32 is reduced.

[0062] In the case where the insulating layer has three or more layers, the ratio of the elastic modulus of the insulating layer 31 in contact with the first electrode 20 and the insulating layer 32 in contact with the second electrode 40 can be set to a range of 2 to 2000, similarly to the case of the two layers, and the elastic modulus of the insulating layer formed between the insulating layer 31 and the insulating layer 32 can be set to an intermediate value between the elastic modulus of the insulating layer 31 and the elastic modulus of the insulating layer 32. In addition, even if the insulating layer 31 and the insulating layer 32 have the same material and thickness, countersunk concavities and convexities can be formed on the surface of the insulating layer 30 as described later to make the elastic modulus of the insulating layer 32 lower than the elastic modulus of the insulating layer 31.

[0063] In addition, the insulating layer 30 may also have layers. For example, if the insulating layer 30 is made into a layered structure in terms of the values ​​of physical properties or chemical properties such as elastic modulus, material density, hardness, shear strength, etc., the internal stress strain generated in the insulating layer can be moderately reduced, thereby having the effect of reducing the load of the shear force applied to the insulating layer and improving the durability of the insulating layer and other layers. In addition, since the internal stress strain that becomes noise is reduced, the detection sensitivity is also improved, and as a result, the shear force can be measured more accurately. Moreover, this effect has the effect of being applicable not only to the ground pressure distribution in the Z-axis direction in the past, but also to the ground pressure distribution of the shear force, and as a result, it has the effect of being able to distinguish between pressure detection and shear force detection. It should be noted that the insulating layer 30 having layers means that the insulating layer 30 is not a uniform layer of film, but as long as it is a film with a structure in which the physical properties or chemical properties change in a certain direction (especially the Z-axis direction), the number of stages of the layers, the degree of lightness and darkness, etc. are not particularly limited.

[0064] As a method of giving the insulating layer 30 a layer by layering the density of the material, there can be mentioned a method of forming the insulating layer 30 with a plurality of foam layers, and changing the concentration of the bubbles and the bubble size 300 in stages. That is, the insulating layer 30 is formed into a three-layer structure of, for example, a foam layer, and a foaming agent is mixed with the main material of the insulating layer 30 at different ratios for each layer, or a foaming agent with different bubble sizes is mixed with each layer of the insulating layer 30, dispersed, and molded by applying heat, thereby obtaining an insulating layer 30 composed of three layers of foam bodies each containing different bubble concentrations or bubble sizes 300 (see Figure 4 ).

[0065] In this case, the elastic modulus of each layer in the insulating layer 30 becomes different, and the above-mentioned effect of protecting the first electrode 20 from damage and degradation and the effect of accurately measuring the measured value of the shear force can be obtained. On the other hand, since the main material of each layer in the insulating layer 30 is completely the same, the interlayer adhesion in the insulating layer 30 is high and the durability of the insulating layer 30 is also improved. As another method of giving the insulating layer 30 a layer, there is a method of controlling the density, hardness, elastic modulus, and shear strength of the material of the insulating layer by forming a countersunk concave-convex 70 in the insulating layer 30 (see Figure 5 If the insulating layer 30 is formed of a foamed body or the countersunk unevenness 70 is formed in advance, the following effect is achieved: even if the shear force 60 is applied and the reaction of the shear force 60 causes excessive swelling of the second electrode 40 and the protective layer 50, the bubbles in the insulating layer 30 and the countersunk unevenness 70 absorb the swelling and reduce the swelling.

[0066] Furthermore, the insulating layer 30 is preferably configured with a Poisson's ratio in the range of 0 to 0.48. The Poisson's ratio referred to in the present invention refers to a value obtained by cutting the insulating layer 30 into the shape of a dumbbell No. 1 test piece, using a non-contact elongation width meter capable of measuring minute displacements, measuring the longitudinal strain (change in the axial direction / original length in the axial direction) and the transverse strain (change in the width direction / original length in the width direction) by a tensile test method in accordance with JIS K7127 and JIS K7161, and dividing the transverse strain value by the longitudinal strain value.

[0067] In addition, when the insulating layer 30 is a very thin film, for example, or when the insulating layer 30 is integrated with the substrate 10 and the second electrode 40 and cannot be completely separated, and a tensile test of the insulating layer 30 alone cannot be performed, the value measured in the same manner as above is set as the value of the Poisson's ratio of the present invention, under the condition that the insulating layer 30 occupies more than 90% of the total volume of the stacked body of the insulating layer 30, the substrate 10, and the second electrode 40 are placed thereon.

[0068] If the Poisson's ratio is less than 0, when the insulating layer 30 is pressed through the protective layer 50, the unpressed portion also sags, and thus a significant detection error is likely to occur. On the other hand, if the Poisson's ratio exceeds 0.48, the unpressed portion bulges, and thus a significant detection error is likely to occur. As a method for reducing the Poisson's ratio, the following method can be cited: forming a countersunk concave-convex portion 70 on the surface of the insulating layer 30, so that the bulge of the protective layer 50 when pressed enters the concave portion of the insulating layer 30, thereby preventing the insulating layer 30 from bulging excessively (see Figure 5 The shape of the countersunk unevenness can be appropriately selected according to the material and thickness of the insulating layer 30 .

[0069] As the material of the insulating layer 30, there can be cited elastic synthetic resin sheets such as silicone, fluorine, urethane, epoxy, ethylene-vinyl acetate copolymer, polyethylene, polypropylene, polystyrene, butadiene rubber, and stretchable non-woven fabric sheets. In particular, silicone resin-based elastomer sheets such as silicone and silicone elastomers have excellent durability in a wide temperature range from low temperature to high temperature, and also have excellent elasticity, so they are more preferred. It should be noted that the insulating layer 30 is not limited to being formed into sheets by general sheet forming methods such as extrusion molding, but can also be a coating formed by printing, a coater, etc. The thickness can be appropriately selected within the range of 20μm to 5mm.

[0070] Silicone is a material that becomes gel after curing with organic polysiloxane as the main component. It has the unique properties of silicone such as durability and high safety and sanitation, as well as the characteristics of softness, impact absorption, and moisture resistance due to low crosslinking density (low density of the mesh structure formed by chemical bonding between chain polymers). There are mainly room temperature curing type and heat curing type, and the curing speed varies according to the type of curing agent, the increase or decrease of the added amount, temperature adjustment, etc. It should be noted that the silicone hydrogel obtained by mixing silicone with hydrophilic gels such as polyvinyl pyrrolidone and polyvinyl chloride thermoplastic elastomers also belongs to a type of silicone of the present invention. As a method for manufacturing the insulating layer 30 with silicone, there are: a method of adding a catalyst with a curing-accelerating effect and a silicone rubber material to a silicone material to make a compound raw material, and a method of sheeting with various coaters such as a lip coater, a notch wheel coater, a reverse coater, and a blade coater; a method of coating the silicone material on a pre-prepared silicone rubber sheet with the above-mentioned various coaters to form an integral mold.

[0071] In addition to thermosetting silicone elastomers obtained by crosslinking straight-chain silicone rubber compounds or liquid silicone rubbers with vulcanizers or catalysts, silicone elastomers also include thermoplastic silicone modified elastomers obtained by mixing silicone oil with other elastomers such as urethanes or copolymerizing with reactive silicone oils. As a method for manufacturing the insulating layer 30 using silicone elastomers, there can be cited the following methods: adding a reinforcing agent and a vulcanizing agent to the above-mentioned silicone raw materials, stirring and mixing, and rolling molding into sheets using a rolling mill of a predetermined thickness. In addition, there can be cited: press molding by injecting into a predetermined mold and applying heat and pressure to vulcanize, extrusion molding by using an extruder to form sheets, calendering molding using a calendering roll to form a wide long sheet, coating molding using a coating device to apply to a substrate such as glass cloth, injection molding, winding molding, etc. In addition to the catalyst, stabilizers can also be added to these silicone resin elastomer sheets. Examples of the catalyst include nitrogen-containing compounds such as triethylamine and triethylenediamine, metal salts such as potassium acetate, zinc stearate, and tin octoate, and organic metal compounds such as dibutyltin dilaurate. Examples of the stabilizer include stabilizers against ultraviolet rays such as substituted benzotriazoles, and stabilizers against thermal oxidation such as phenol derivatives.

[0072] In addition, as an example of the insulating layer 30 being composed of a foam, there can be cited an insulating layer formed into a foamed or porous shape by finely dispersing gas in the synthetic resin of the insulating layer 30. In particular, polyethylene, polypropylene, polystyrene, etc., have weak elasticity when they are only sheets, and elasticity is generated by forming them into a foam. Therefore, when these synthetic resins are selected as the material of the insulating layer 30, it is preferable to make them into a foamed state in advance. The method for manufacturing the foam can be cited as: dispersing a heat-expandable microcapsule foaming agent obtained by encapsulating a thermal decomposition type foaming agent such as azodicarbonamide, bicarbonate, freon, hydrocarbon, etc. with a thermoplastic resin capsule in the above-mentioned synthetic resin, and manufacturing it by a molding method such as bead foaming, batch foaming, pressurized foaming, normal pressure secondary foaming, injection foaming, extrusion foaming, foam blow molding, etc. by applying heat.

[0073] The bubble size 300 of the foam is preferably 2 μm to 100 μm. As a method for manufacturing a foam having such a bubble size, it is preferred to control the atmospheric pressure (external air pressure) by reducing or pressurizing it to a certain pressure during the reaction process of vulcanization foaming. This is because, by controlling within this range, the growth of bubbles during vulcanization foaming can be promoted or hindered, and a foam having a certain desired foaming ratio and a certain cell size can be obtained. In addition, it is because the range of the foaming ratio can be greatly expanded, and a product with a desired foaming ratio can be obtained. Among the foams, a silicone foam made of a silicone resin is preferred. It has the advantages of less elastic changes caused by temperature and can also cope with measurements at low temperatures, and has high durability, so even if it is repeatedly subjected to strain and stress caused by large displacement, it can prevent breakage and deformation. As a result, it can be used in devices for measuring ground contact in various fields, such as measuring objects with large loads such as tires and even measuring objects with small loads such as soles.

[0074] Silicone foam is a foam obtained by independently or semi-independently foaming silicone rubber. In addition to the type in which a foaming agent is added to silicone rubber and heated to foam as described above, there are also self-foaming reaction types composed of two-component liquid silicone. As a method for manufacturing the insulating layer 30 using self-foaming reaction type silicone foam, there are: a calendaring method in which a liquid silicone rubber raw material is sandwiched between two carrier sheets and thinned between calendaring rollers to form a sheet shape for vulcanization and foaming; a free foaming method in which a liquid silicone rubber raw material is loaded onto a sheet in an unrestricted form for vulcanization and foaming; an injection molding method in which a liquid silicone raw material is injected into a mold for vulcanization and foaming, etc.

[0075] In addition, the insulating layer 30 may also be composed of an electroviscous fluid. An electroviscous fluid is a fluid whose viscoelastic properties change reversibly by applying or removing an electric field, and examples include a homogeneous electroviscous fluid composed of a single substance such as liquid crystal, a dispersed electroviscous fluid in which particles are dispersed in an insulating liquid, etc. In particular, in the case of a dispersed electroviscous fluid, a solid-liquid phase change can be performed according to the presence or absence of an electric field, so it is more preferred. As particles used in the dispersed electroviscous fluid, porous particles composed of carbonaceous and insulating materials can be cited. The average particle size of the particles is preferably 5 to 30 μm. As an insulating liquid for a dispersed electroviscous fluid, silicone oil can be cited. In addition, a crosslinking agent, a platinum catalyst, etc. can also be added to the insulating liquid and heat-treated to gel the electroviscous fluid. For a sheet of a gelled electroviscous fluid, by applying an electric field, the particles are buried in the gel and the surface state changes. That is, the gel bulges due to the electric force of the interface, and the surface becomes a smooth and flush state of only the gel, and contacts with the entire surface of other layers to become a state showing adsorption. In such a state, shear stress is easily transmitted to the insulating layer 30, and the detection sensitivity is improved. The method for producing the dispersed electroviscous fluid can include the following method: dried porous particles are added to the electrically insulating liquid while being stirred at a temperature maintained above the decomposition temperature of the electrically insulating liquid, thereby decomposing the electrically insulating liquid present near the porous particles to generate low molecular weight organic compounds, and the organic compounds are uniformly adsorbed on the surface of the porous particles.

[0076] In addition, conductive particles 80 such as carbon black, gold, silver, and nickel may be added to the insulating layer 30 in a ratio within a range in which the insulating property can be maintained (see Figure 5 This is because, when the insulating layer 30 is pressed, the distance between the conductive particles contained therein is close, and the capacitance value between the first electrode 20 and the second electrode 40 increases sharply, thereby having an effect of improving the sensitivity of pressure and shear force based on the calculation method of the shear force 60 described later. The average particle size of the conductive particles 80 is preferably less than 1 / 10 of the thickness of the insulating layer 30.

[0077] Next, the first electrode 20 and the second electrode 40 are described. The material of the first electrode 20 and the second electrode 40 may include, in addition to metal films of gold, silver, copper, platinum, palladium, aluminum, rhodium, etc., conductive paste films in which these metal particles are dispersed in a resin binder, or organic semiconductors such as polyhexylthiophene, polydioctylfluorene, pentacene, and tetrabenzoporphyrin, but are not particularly limited. Regarding the formation method, in the case of the former, a method of forming a conductive film on the entire surface by plating, sputtering, vacuum evaporation, ion plating, etc., and then patterning by etching can be cited. In the case of the latter, a method of directly forming a pattern by printing methods such as screen, gravure, offset printing, etc. can be cited.

[0078] The first electrode 20 is formed on the substrate 10 located below the insulating layer 30 (see Figure 1 to Figure 5 ) is preferred. As the substrate 10, glass epoxy substrates, polyimide substrates, polybutylene terephthalate resin substrates, etc. can be cited, but there is no particular limitation. The thickness can be appropriately selected between 0.1 mm and 3 mm. The second electrode 40 is mainly formed on the upper part of the insulating layer 30, and can be composed of only one layer or two layers 401, 402 (see Figure 1 ) or a multilayer structure of the above. The pattern of the second electrode 40 may be any shape such as circular, square, linear, etc. The thickness of the second electrode 40 may be appropriately selected within the range of 0.1 μm to 100 μm.

[0079] As the pattern of the first electrode 20 and the second electrode 40, a pattern consisting of linear patterns and extending in the same direction when viewed from above can be cited (see Figure 6 ). The second electrode 40 and the first electrode 20 are formed of linear patterns extending in the same direction, so that when a shear force 60 is applied from a direction intersecting with a direction in which the linear pattern of the second electrode extends, the second electrode 40 is deformed according to the magnitude of the shear force 60, and the distance between the second electrode 40 and the first electrode 20 changes, and the magnitude of the force can be measured by detecting an electrical signal when the capacitance value between the second electrode 40 and the first electrode 20 changes.

[0080] For example, the first electrode 20 is composed of linear patterns 25, 26, and 27 extending in one direction, and the second electrode 40 is also linear patterns 45 and 46 extending in the same direction as the first electrode 20, and is formed at the gap between the pattern 25 and the pattern 26 and the gap between the pattern 26 and the pattern 27 (see Figure 6 ). If a shear force 60 is applied along the surface of the protective layer 50 on the uppermost surface of the capacitance detection device 1 in a direction intersecting with a direction in which the linear patterns 45 and 46 of the second electrode 40 extend, then, depending on the magnitude of the shear force 60, the linear patterns 45 and 46 of the second electrode 40, together with the protective layer 50 and the insulating layer 30, are deformed (moved in parallel) in the direction to which the shear force 60 is applied to the right side of the paper, and the distance between the linear pattern 26 of the first electrode 20 becomes closer to the linear pattern 45 and farther from the linear pattern 46. In addition, the linear pattern 25 of the first electrode 20 becomes farther from the linear pattern 45, and the linear pattern 27 of the first electrode 20 becomes closer to the linear pattern 46 (refer to Figure 7 ). The change in the distance between the layers of these linear patterns is proportional to the magnitude of the shear force 60. Therefore, by detecting the change in the capacitance value between the linear patterns caused by the change in the distance between the layers of these linear patterns, the magnitude of the shear force 60 can be detected.

[0081] This example describes the case where the first electrode 20 has three linear patterns and the second electrode 40 has two linear patterns, but it can also be only one or more than four. In addition, the number of linear patterns of the first electrode 20 and the second electrode 40 can also be the same. In addition, this example describes that the linear patterns of the first electrode 20 and the second electrode 40 are both substantially the same shape of long rectangular strips, but the widths and lengths can be different (see Figure 8 a), or a shape where the width is partially widened or partially narrowed (see Figure 8 b). In addition, the shape may be not only a rectangular shape but also a polygonal shape or a curved shape such as an arc shape (see Figure 8 c). In addition, it can also be a composite shape or a wavy shape (see Figure 8 d) It should be noted that these square and circular shapes usually do not belong to the category of linear patterns, but in the present invention, as long as they are in a form that presents the effects and functions of the present invention, they are regarded as a type of linear pattern and belong to the scope of the present invention.

[0082] In addition, the first electrode 20 and the second electrode 40 may each be a multilayer. For example, the first electrode 20 may be a two-layer structure consisting of a lower first electrode 21 and an upper first electrode 22 sandwiching an insulating film, and the second electrode 40 may be a two-layer structure consisting of a lower second electrode 41 and an upper second electrode 42 sandwiching an insulating film (see Figure 9-1 In this case, the first electrode 20 is preferably configured as a lower first electrode 21 of a linear pattern extending in the X direction and an upper first electrode 22 of a linear pattern extending in the Y direction (see Figure 9-2 (a)), the second electrode 40 is set to be a lower second electrode 41 of a linear pattern extending in the X direction similarly to the above-mentioned lower first electrode 21 and an upper second electrode 42 extending in the Y direction similarly to the above-mentioned upper first electrode 22 (see Figure 9-2 (b)).

[0083] In addition, Figure 9-1In the example of forming two layers of second electrodes 40 on the upper part of the two layers of first electrodes 20, it is also possible to form the layers of the first electrode and the second electrode alternately. That is, it is also possible to form the lower second electrode 41 on the lower first electrode 21, form the upper first electrode 22 thereon, and form the upper second electrode 42 thereon. In either case, the lower first electrode 21 can be covered and hidden by the lower second electrode 41 with a large cross-sectional area, and the upper first electrode 22 can be covered and hidden by the upper second electrode 42 with a large cross-sectional area, so there is an advantage that the circuit patterns of the lower first electrode 21 and the upper first electrode 22 inside cannot be recognized from the appearance. It should be noted that if covering and hiding is not required, the cross-sectional area of ​​each electrode can be made the same, and conversely, the cross-sectional area of ​​the two internal layers of electrodes can be increased.

[0084] In this way, the change in capacitance between the lower first electrode 21 and the lower second electrode 41 and the change in capacitance between the upper first electrode 22 and the upper second electrode 42 can be detected separately. Alternatively, the change in capacitance between the lower first electrode 21 and the upper second electrode 42 and the change in capacitance between the upper first electrode 22 and the lower second electrode 41 can be detected separately. As a result, there is the following advantage: even if the direction in which the shear force 60 is applied is oblique when viewed from above, and there are X-direction force components 65 and Y-direction force components 66 in the shear force 60 (when the direction of the shear force 60 is not parallel to or at right angles to the direction of any linear pattern in the upper first electrode 41 or the upper second electrode 42), the X-direction and Y-direction force components 65 and 66 of the shear force 60 can be measured separately. It should be noted that in Figure 9-2 In the figure, an example is shown in which each electrode is a linear pattern in the same direction as either the X direction or the Y direction, but this advantage can be enjoyed even if the linear pattern is not in the same direction as either the X direction or the Y direction, so the scope of the present invention is not limited to the linear pattern in the same direction as either the X direction or the Y direction.

[0085] Furthermore, if a capacitance detection device group 100 is formed by arranging a plurality of capacitance detection devices 1 of the present invention in a vertical and horizontal matrix, the planar distribution of the shear force 60 in a direction intersecting an angle with one direction of each capacitance detection device 1 can also be measured (see Fig.10 That is, each capacitance detection device 1 can respectively measure the force in the direction of the angle intersecting the capacitance detection device 1 at each position. Therefore, even if the magnitude of the shear force 60 varies depending on the position, if a plurality of capacitance detection devices 1 are arranged in a vertical and horizontal matrix, the magnitude of the shear force 60 at each position can be measured.

[0086] Furthermore, if a plurality of capacitance detection devices 1 of the present invention each having a plurality of layers of the second electrode 40 and the first electrode 20 are arranged in a vertical and horizontal matrix to form a capacitance detection device group 100, it is also possible to measure the component forces 65 and 66 of the shear force 60 in the X direction and the Y direction of each capacitance detection device 1, and it is also possible to measure the surface distribution of the component forces 65 and 66 of the shear force 60 in the X direction and the Y direction (see Fig.11 That is, each capacitance detection device 1 can respectively measure the force component (the force component in the X direction and the force component in the Y direction) of the force in the direction of the angle intersecting the capacitance detection device 1 at each position. Therefore, even if the magnitude and direction of the shear force 60 differ depending on the position, if a plurality of capacitance detection devices 1 are arranged in a vertical and horizontal matrix, the magnitude of the force component (the force component 65 in the X direction and the force component 66 in the Y direction) of the shear force 60 at each position can be measured.

[0087] In addition, the above example shows the case where the capacitance detection devices 1 are arranged in a vertical and horizontal matrix, but the capacitance detection devices 1 may also be arranged in a vertical row or a horizontal row. In addition, the capacitance detection device group 100 may be, for example, a form in which the second electrode 40 and the first electrode 20 are formed separately and independently on the basis of the common substrate 10 and the insulating layer 30 to form each capacitance detection device 1, or a form in which the already manufactured capacitance detection devices 1 are laminated and arranged one by one on another large substrate.

[0088] In addition, there is also a mode in which the first electrode 20 is composed of an island pattern, and the second electrode 40 is composed of two layers of an upper second electrode 402 and a lower second electrode 401 (see Figure 12-1 ), and the upper second electrode 402 and the lower second electrode 401 are composed of a plurality of linear patterns that intersect when viewed from above (refer to Figure 12-2 ), a portion of the island pattern of the first electrode 20 overlaps with a portion of the pattern of the upper second electrode 402 and a portion of the pattern of the lower second electrode 401 when viewed from above (refer to Figure 12-3 ). In this top view, the angle at which the upper second electrode 402 and the lower second electrode 401 intersect is not limited. When they are orthogonal (i.e., the angle of intersection is 90°), the pattern of the first electrode 20 becomes a rectangular checkerboard (refer to Figure 12-3 ), when not orthogonal, the pattern of the first electrode 20 becomes a parallelogram checkerboard (refer to Fig.13 ).

[0089] In any case, it is preferred that the area of ​​a region where a portion of the island pattern of the first electrode 20 overlaps with a portion of the pattern of the upper second electrode 402 when viewed from above (hereinafter referred to as S1) is larger than the area of ​​a region where a portion of the island pattern of the first electrode 20 overlaps with a portion of the pattern of the lower second electrode 401 (hereinafter referred to as S2). The capacitance value between electrodes is inversely proportional to the distance between electrodes, so the distance between the first electrode 20 and the upper second electrode 402 is farther than the distance between the first electrode 20 and the lower second electrode 401, so the detection sensitivity of the capacitance value is correspondingly reduced. Therefore, in order to compensate for the reduced sensitivity, by making S1 larger than S2 when viewed from above, the sensitivity of the first electrode 20 and the upper second electrode 402 is increased, the sensitivity of the first electrode 20 and the upper second electrode 402 can be made the same as the sensitivity of the first electrode 20 and the lower second electrode 401, and the detection sensitivity of the shear force 60 in the X direction can be made the same as the detection sensitivity in the Y direction.

[0090] In addition, when the upper second electrode 402 is orthogonal to the lower second electrode 401 in a plan view, the pattern of the first electrode 20 may be not a rectangle but a rectangle with rounded corners and no vertices (see FIG. Fig.14 ). Similarly, when the upper second electrode 402 and the lower second electrode 401 are not orthogonal when viewed from above, the pattern of the first electrode 20 may be set not as a parallelogram, but as a parallelogram with rounded corners and no four vertices. In addition, when the upper second electrode 402 and the lower second electrode 401 are orthogonal when viewed from above, the pattern of the first electrode 20 may be set not as a rectangle, but as a vertically long ellipse (see Figure 15-1 , Figure 15-2 ). In this case, compared with the case of setting it as a rectangle, the area of ​​S1 is separated from the area of ​​S2, so the adverse effects caused by the noise of the electrical signals generated at each electrode are also reduced. In addition, the ratio of the increased area of ​​S1 (hereinafter referred to as S1′) caused by the parallel movement of the upper second electrode 402 from the right to the left of the paper surface caused by the shear force 60 applied from the right to the left of the paper surface (i.e., (S1+S1)′) / S1 ratio) is larger than that of the rectangular and parallelogram patterns, so the ellipse has a higher advantage than the rectangle and parallelogram in terms of the increased sensitivity to noise detection. Similarly, the ratio of the increased area of ​​S2 (hereinafter referred to as S2′) caused by the parallel movement of the lower second electrode 401 from the upper and lower sides of the paper surface caused by the shear force 60 applied from the upper and lower sides of the paper surface (i.e., (S2+S2)′) / S2 ratio) is larger than that of the rectangular and parallelogram patterns, so the ellipse has a higher advantage than the rectangle and parallelogram in terms of the increased sensitivity to noise detection.

[0091] In addition, it can also be set to a pattern that is between the shape of the above-mentioned rectangle with rounded corners and no four vertices and the shape of an ellipse. It should be noted that the island pattern of the first electrode 20 can be formed by arranging multiple identical patterns, or by arranging multiple mixed patterns. In addition, in any of the above-mentioned figures, the linear patterns of the upper second electrode 402 and the lower second electrode 401 are recorded as long rectangles of approximately the same shape, but their widths and lengths can be different (refer to Figure 8 a), or a pattern where the width is partially widened or narrowed (see Figure 8 b). In addition, the pattern may be partially or entirely polygonal or arc-shaped (see Figure 8 c), or a composite pattern or a wave-shaped pattern (see Figure 8 d) Furthermore, it is preferred that the island pattern of the first electrode 20 is appropriately changed according to the linear patterns of the upper second electrode 402 and the lower second electrode 401.

[0092] In the above, various examples of the island pattern of the first electrode 20 and the linear patterns of the upper second electrode 402 and the lower second electrode 401 of the second electrode 40 are shown. Hereinafter, a detailed description will be given with an eye on an example in which the island pattern of the first electrode 20 is a slightly vertically elongated rectangle and the linear patterns of the upper second electrode 402 and the lower second electrode 401 are straight-line rectangles (refer to Figure 12-4 to Figure 12-6 ). In this case, it is preferred that the distance d40 between the ends of the intersection where the upper second electrode 402 and the lower second electrode 401 intersect when viewed from above and which is the distance in the pattern direction of the upper second electrode 402 is greater than the distance d20 between the centers of the intersection where the upper second electrode 402 and the lower second electrode 401 intersect when viewed from above. Furthermore, the first electrode 20 of the island pattern preferably has the vertices of its rectangle located within the region where the upper second electrode 402 and the lower second electrode 401 intersect when viewed from above. (Refer to Figure 12-4 ).

[0093] By measuring the change in capacitance between the first electrode 20 of the island pattern and the upper second electrode 402 and the change in capacitance between the first electrode 20 of the island pattern and the lower second electrode 401, the X-axis component 65 of the shear force 60 in the pattern direction of the upper second electrode 402 and the Y-axis component 66 of the shear force 60 in the pattern direction of the lower second electrode 401 can be measured respectively. The region where the capacitance between the first electrode 20 of the island pattern and the upper second electrode 402 can be detected is S1, i.e. Figure 12-4On the other hand, the region where the capacitance value between the first electrode 20 of the island pattern and the lower second electrode 401 can be detected is S2, that is, Figure 12-4 In addition, the average thickness distance t40 between the first electrode 20 of the island pattern and the upper second electrode 402 is greater than the average thickness distance t20 between the first electrode 20 of the island pattern and the lower second electrode 401 (i.e., the lower second electrode 401 is closer to the first electrode 20 of the island pattern than the upper second electrode 402). Therefore, for the region where the first electrode 20, the upper second electrode 402 and the lower second electrode 401 overlap, the function of S2 (gray filled portion) is more dominant. (Refer to Figure 12-4 ).

[0094] If a force component 65 in the X-axis direction is applied from the right to the left on the paper in this state, then in proportion to the magnitude of the force, Figure 12-4 The upper second electrode 402 is Figure 12-5 The position of the upper second electrode 402 is moved parallel to the left side of the paper, and as a result, the area S1 capable of detecting the capacitance value between the first electrode 20 and the upper second electrode 402 is moved from Figure 12-4 The status of increase Figure 12-5 The area of ​​the black filled area S1′ in the state. Figure 12-5 By looking at the increased capacitance value of the black filled area S1′, the original X-axis force component 65 can be measured. Figure 12-4 In the state of , a component force 66 in the Y-axis direction is applied from the top to the bottom of the paper, and proportionally to the magnitude of the force, Figure 12-4 The lower second electrode 401 is Figure 12-6 The position of the lower second electrode 401 is moved parallel to the paper surface (i.e., moved parallel to the lower direction of the paper surface), and as a result, the area S2 capable of detecting the capacitance value between the first electrode 20 and the lower second electrode 401 is moved from Figure 12-4 The status of increase Figure 12-6 Therefore, by detecting the increased capacitance value of the black-filled region S2', the original component force 66 in the Y-axis direction can be measured.

[0095] The detection sensitivity of the capacitance value change caused by the component force 65 in the X-axis direction and the component force 66 in the Y-axis direction of the shear force 60 is preferably set to be approximately the same in the X-axis direction and the Y-axis direction, so it is preferred to make Figure 12-5 The area of ​​the black filled region S1′ is larger than Figure 12-6 That is, this is because the distance between the upper second electrode 402 and the first electrode 20 is farther than that between the lower second electrode 401 (refer to Figure 12-1 ), so if the area of ​​S1′ is made the same as the area of ​​S2′, the detection sensitivity at the upper second electrode 402 will usually become lower than the detection sensitivity at the lower second electrode 401. Specifically, it can be designed to be t20 / t40 (the distance between the first electrode 20 and the lower second electrode 401 / the distance between the first electrode 20 and the upper second electrode 402) ≒ S2′ / S1′ ( Figure 12-6 The area of ​​the black filled area / Figure 12-5 Therefore, if the difference between t20 and t40 is so small that it can be ignored and they can be regarded as completely the same, the area of ​​S2′ can also be set to be the same as the area of ​​S1′.

[0096] Next, the wiring of the first electrode 20, the second electrode 40 and the processing unit 120 will be described in detail. The wiring pattern can be connected from each first electrode 20 to be electrically connected to the processing unit 120 via the independent AC drive circuit 5 and the drive circuit 110. On the other hand, the second electrode 40 can be electrically connected to the processing unit 120 via the signal conversion unit 130 (see Figure 1 , Fig.16 ). In this way, if the first electrodes 20 of complex and fine patterns are each electrically connected to the processing unit via an independent AC drive circuit 5 of the same complex and fine pattern, the change in the capacitance value generated between the first electrode 20 and the second electrode 40 in each very fine range can be detected with very high accuracy, so the shear force 60 applied from the second electrode 40 or the protective layer 50 can be measured very accurately. In addition, the first electrode 20 and the second electrode 40 can also be switched. That is, the second electrode 40 can be formed on the substrate 10, the first electrode 20 can be formed on the insulating layer 30, the first electrode 20 located at the upper part is connected to the independent AC drive circuit 5, and the first electrode 20 located at the lower part is connected to the signal conversion unit 130.

[0097] An independent AC driving circuit 5 is formed corresponding to each of the electrodes 21 of the first electrode 20, and the independent AC driving circuit 5 is connected to the processing unit 120 via the driving circuit 110 (see Fig.16). The processing unit 120 controls the independent AC driving circuit 5 via the driving circuit 110, and applies an alternating current signal (AC signal) to each of the electrodes 21 of the first electrode 20. Then, current is passed into a certain independent AC driving circuit 5 in the switch-off state where no current flows, until it is saturated and changes to the switch-on state, and the current passed into the other independent AC driving circuit 5 that is saturated and becomes the switch-on state is cut off to change it to the switch-off state, thereby realizing the switching of the driving circuit 110. From the perspective of reducing power consumption, the current passed into the driving circuit 110 is preferably small, but if it is too small, it is easily affected by noise, so it is preferably set to 10μA to tens of mA. In addition, the driving circuit 110 mentioned in the present invention is a circuit that drives the independent AC driving circuit 5, and switching the driving circuit 110 means changing the flow of the output signal from the processing unit to another circuit. That is, the driving circuit 110 is a circuit that has the function of changing the flow direction of the current as the output signal, or controlling the amount of current passed within a controllable range.

[0098] The independent AC drive circuit 5 is a circuit having two or more inputs received from the respective electrodes 21 of the first electrode 20 and one output for outputting an AC signal to the first electrode 20, and changing the AC signal according to the input signal pattern from the first electrode 20. The independent AC drive circuit 5 is preferably a logic circuit type. This is because, in the case of the logic circuit type, a type with two inputs and one output (AND (AND operation), OR (OR operation), NAND (NAND operation), XOR (Exclusive OR operation)) can be used, which has the effect of reducing the number of signal lines. For example, when using AND (AND operation), although a rectangular wave AC signal is always output to INA (input A), the signal is output from OUT (output) only when INB (input B) is HIGH (refer to Fig.17 ). In addition, Fig.16 In the embodiment, the independent AC driving electrode 5 is arranged on the opposite side of the substrate 10 to the first electrode 20 and is connected to the first electrode 20 through the through hole, but may be arranged in parallel on the same side as the first electrode 20 .

[0099] In addition, the connection wirings of each electrode 21 of the first electrode 20, the independent AC drive circuit 5, and the drive circuit 110 are often formed with a larger number of wirings in practice, but Fig.16 In order to simplify the description, the first electrode 20 is described as 4×5=20. The independent AC drive circuits 5 in the same row share the input terminal, and the independent AC drive circuits 5 in the same column share the input terminal. Therefore, the first electrode 20 is controlled by 4+5=9 signal lines. As an example, Fig.18 It is shown in Fig.16 An example of signals of nine signal lines when three of the electrodes 21 of the first electrode 20 (col1 (column 1), row2 (row 2)), (col1 (column 1), row3 (row 3)), and (col4 (column 4), row3 (row 3)) independently output AC signals (AC drive). This is a case where the independent AC drive circuit 5 is an AND circuit, and it can be appropriately changed in the case of other circuits. When the first electrode 20 is independently AC driven, the second electrode 40 receives a signal according to the size of the capacitance between each of the first electrodes 20 and the second electrode 40.

[0100] When the independent AC drive circuit 5 is set to a logic circuit type, the capacitance detection device 1 preferably sets each capacitance value and resistance value in a manner that satisfies the condition of (capacitance value generated between the second electrode 40 and the first electrode 20 + parasitic capacitance of the first electrode 20) × output resistance value of the logic circuit <1μs (time constant: 1 microsecond). This is because the time constant is usually preferably increased, but if the time constant is higher than 1μs, the undesirable situation of reduced switching speed sometimes occurs. It should be noted that the time constant refers to the product of the resistance value and the capacitance value in an RC circuit (i.e., a circuit composed of a resistor and a capacitor and driven by a voltage or current). In addition, parasitic capacitance refers to the capacitance value generated in the first electrode 20 due to a physical structure not intended by the designer. The electrode materials of the independent AC drive circuit 5 and the drive circuit 110 are not particularly limited. In addition to metal films of copper, silver, gold, nickel, aluminum, etc., conductive inks, indium tin oxide, zinc oxide, etc. containing them can also be used. The formation method includes: forming a conductive film on the entire surface by plating, sputtering, vacuum evaporation, ion plating, etc., and then patterning by etching. The pattern can be any shape such as circular, square, linear, etc. The thickness is preferably selected appropriately within the range of 0.1 μm to 5 mm.

[0101] In addition, the independent AC drive circuit 5 can also be composed of thin film transistors. This is because, in a simple logic circuit type, only rectangular waves can be output, but in the case of being formed by thin film transistors, it has the effect of being able to output more complex AC signals such as sine waves. For thin film transistors, it is preferred to select transistors with fast switching speed and large maximum collector current. This is because when the switching speed is fast, the capacitance value in each electrode 21 can be quickly measured almost simultaneously, and when the maximum collector current is large, the obtained signal can be transmitted faster accordingly. Therefore, if the charge accumulated in the thin film transistor is insufficient (the capacitance value is low), the switching speed is sometimes reduced, so it is preferred to make the resistance value when the transistor is electrically connected small enough. This is because, by reducing the resistance value when the transistor is electrically connected, the current flowing between the transistors becomes more, and as a result, charging is promoted to fully replenish the charge, and the capacitance value increases.

[0102] It should be noted that, when the thin film transistor is not electrically connected, in order to avoid the disappearance of the accumulated charge, it is usually preferred to fully increase the time constant ((the capacitance value generated between the second electrode 40 and the first electrode 20 + the capacitance value between the gate / drain of each thin film transistor + the capacitance value between the source / drain when each thin film transistor is turned off + the parasitic capacitance value of the drain) × (the pull-down resistance value or the pull-up resistance value in the element)). On the other hand, if the time constant is higher than 10μs, the undesirable situation of reduced switching speed may sometimes occur. Therefore, the numerical value of the above time constant is preferably less than 10μs. In addition, the pull-down resistance value in the element refers to a resistor that plays a role in realizing a low-level voltage (usually, making the voltage of the signal as a digital circuit become 0 volts) when there is no input (OFF state). In addition, the pull-up resistance value in the element refers to a resistor that plays a role in realizing a high-level voltage (for example, making the voltage of the signal as a digital circuit become 5 volts) when there is no input (OFF state).

[0103] In addition, the resistance value when the thin film transistor is turned on is preferably sufficiently smaller than the pull-down resistance value and the pull-up resistance value in the element. On the other hand, the resistance value when the thin film transistor is turned off is preferably sufficiently larger than the pull-down resistance value and the pull-up resistance value in the element. This is because if the pull-down resistance value and the pull-up resistance value in the element are set in this way, the signal is smoothly transmitted. In addition, the thin film transistor can also be formed by an organic semiconductor. This is because, if an organic semiconductor is used, it can be mass-produced with good productivity by, for example, roll-to-roll, and can also be applied to three-dimensional shapes such as curved surfaces. As materials for such organic semiconductors, for example, substituted thiophene oligomers such as poly-3-hexylthiophene, pentacene and acene, their derivatives, phthalocyanine and thiophene-based fused ring compounds, fluorene oligomer derivatives, etc. The formation method, for example, in the case of poly-3-hexylthiophene, can include drop casting, spin coating, etc. It is preferred that the thickness be appropriately selected within the range of 0.1μm to 5mm.

[0104] The second electrode 40 receives the AC signal emitted from the first electrode 20, and the received AC signal is converted into a voltage in the signal conversion unit 130, and then processed in the processing unit 120. The intensity of the processed AC signal is proportional to the capacitance value between each electrode of the first electrode 20 and the second electrode 40. Thus, the shear force 60 on the upper part of each electrode 21 of the first electrode 20 can be measured, and the surface distribution of the shear force 60 can also be measured. The signal conversion unit 130 is a device unit that converts the AC signal from the second electrode 40 into other signals. As devices constituting the signal conversion unit 130, charge amplifiers, AD converters, distributors, isolators, transducers, etc. can be cited. In this case, the signal conversion unit 130 can be constituted by only a single device, or by a combination of multiple devices. As an example of a combination of multiple devices, a charge amplifier that amplifies and outputs the total amount of the AC current (charge) emitted from the first electrode 20, and an AD converter that converts the amplified analog signal into a digital signal can be cited.

[0105] Next, the protective layer is described. The protective layer 50 is a layer for protecting the first electrode 20 located at the bottom and the second electrode 40 from the shear force 60 applied from the top. As the material of the protective layer 50, in addition to thermoplastic or thermosetting resin sheets such as acrylic, urethane, fluorine, polyester, polycarbonate, polyacetal, polyamide, olefin, etc., ultraviolet curing resin sheets such as cyanoacrylate can also be listed, and there is no particular limitation. However, the protective layer 50 is a layer that also plays a role in accurately transmitting the shear force 60 to the insulating layer 30, so it is necessary to have both the characteristics of a protective film and the characteristics of a pressure transmitter. Therefore, it is preferred to use polyester resins such as acrylic resins, urethane resins, fluorine resins, polyethylene terephthalate, etc. containing more than 10% of acrylic rubber components. The thickness of the protective layer 50 varies depending on the material, but it is preferably selected appropriately between 30μm and 5mm.

[0106] It should be noted that, when the second electrode 40 is a plurality of linear patterns, in order to avoid interference of the electrical signals detected by these linear patterns and thus to avoid noise and thus affecting the sensitivity of the capacitance value to be measured, a cut can be formed on the surface of the protective layer 50. By making the cut, each linear pattern of the second electrode 40 moves independently, so it has the effect of reducing the adverse effects on other electrodes. When the cut is formed, the thickness of the insulating layer 30 is preferably set to be in a slightly thicker range of 500μm to 5mm. As the form of the cut, for example, a dotted line, a short dash line, a long dash line, a single-point dash line, a double-point long dash line, etc. can be cited. The cut can be a single line or multiple lines. The depth of the cut can be formed through the protective layer 50 to the surface of the insulating layer 30, or it can be a half-cut shape up to the middle. As a method for forming the cut, for example, a Thomson knife punching method can be cited.

[0107] Next, the temperature sensor is described. In the capacitance detection device 1 of the present invention, a temperature sensor 800 (see Fig.19 ). This is because, in the case of a device that detects electrical signals such as capacitance values, it is sometimes affected by the ambient temperature. Therefore, in order to minimize this influence, the ambient temperature is measured in real time and the measured value is appropriately corrected. In particular, when the pressed body is a tire or the like, there is considerable friction with the contact surface, so heat is sometimes generated due to the friction, which reduces the accuracy of the measured value. In addition, if the amount of energy loss caused by heat can be estimated, it is possible to estimate the state of the contact surface with less loss, which also has the effect of promoting the development of products with good energy efficiency.

[0108] The temperature sensor 800 can use a thin film sheet with a thickness of 20μm to 3mm that can be bonded or an electrode added to each element of the first electrode. Since it is a small temperature sensor, it can be set in various parts of the capacitance detection device 1, which has the effect of being able to know at which part of the capacitance detection device 1 heat is generated and accumulated. As a result, it has the effect of being able to measure the distribution of both the shear force 60 and the temperature at the same time. As a temperature sensor 800 composed of a thin film sheet, a film-type thermistor temperature sensor in which a thermistor material layer and a temperature sensor electrode are stacked on the film sheet can be cited. The film-type thermistor temperature sensor is a thermistor material layer whose resistance value decreases or increases as the temperature rises, and the temperature is measured by measuring the change in the resistance value using the temperature sensor electrode. The film sheet may include synthetic resin sheets such as polyimide, polyethylene terephthalate, polyethylene naphthalate, polysulfone, polyetherimide, polyetheretherketone, polycarbonate, polyacetal, and liquid crystal polymer, as well as thin film glass, ceramics, and heat-resistant nonwoven fabrics. Alternatively, it may be a sheet having a heat-resistant insulating film formed on a metal sheet. The thickness is preferably selected appropriately within the range of 20 μm to 3 mm.

[0109] In addition to the oxides of transition metals such as manganese, cobalt, and iron, the material of the thermistor material layer can also include nitrides composed of any one of thallium, niobium, chromium, titanium, and zirconium and any one of aluminum, silicon, and bismuth. The former manufacturing method can include the following method: using the oxides of the above-mentioned transition metals as raw materials, mixing them with a mixer, pre-burning, using granulation methods such as pressure granulation and spray drying to make particles of appropriate size, and pressurizing to form a desired shape. The latter manufacturing method can include a method of using a material containing the above-mentioned elements as a target and performing pattern formation by sputtering in a nitrogen-containing atmosphere. In addition, in order to obtain stable thermistor characteristics, these thermistor material layers are preferably formally fired at high temperatures. The material of the temperature sensor electrode can include metal electrode layers such as gold, silver, and palladium, which can be patterned into a comb shape with glass micropowder (glass powder). In addition, in order to improve bonding, a bonding layer of chromium, nickel chromium, titanium nitride, etc. can be set between the film and the temperature sensor electrode. After forming the temperature sensor electrode, the lead wires may be mounted and sealed with epoxy resin or the like to protect the thermistor material layer and the temperature sensor electrode.

[0110] In addition, as temperature sensors other than thermistors, the following types of temperature sensors can be used: a thermocouple method that connects two different metals and utilizes the electromotive force generated by the temperature difference between the two contact points; a temperature measuring resistor method that utilizes the fact that the resistance of a metal changes almost in proportion to the temperature; a thermal expansion method that utilizes the expansion and contraction of liquids and gases due to temperature changes; a bimetallic method that utilizes the phenomenon that when two thin metal plates with different thermal expansion coefficients are bonded together and one end is fixed, the metal plates warp in one direction due to the difference in thermal expansion coefficient when the temperature of the metal plates changes, etc. In addition, the temperature sensor 800 can also function only by additionally forming an electrode in parallel with each element of the first electrode 20 and the second electrode 40. That is, a temperature detection electrode 900 composed of a semiconductor or the like can be provided near the first electrode 20 and the second electrode 40 to replace the temperature sensor 800 (refer to Fig. 20 ). One end side of the temperature detection electrode 900 is connected to the control power supply via a resistor for current limiting, and the other end side is connected to the ground side terminal. In addition, the control power supply is equivalent to a current source that passes a positive current through the temperature detection electrode. In addition to being formed by a metal electrode layer such as gold, silver, palladium, etc., the temperature detection electrode 900 can also be formed by a conductive paste film in which these metal particles are dispersed in a resin adhesive, or an organic semiconductor such as polyhexylthiophene, polydioctylfluorene, pentacene, tetrabenzoporphyrin, etc. With regard to the manufacturing method of the temperature detection electrode 900, in the former case, a method of patterning by etching after forming a conductive film on the entire surface by plating, sputtering, vacuum evaporation, ion plating, etc. can be cited, and in the latter case, a method of directly forming a pattern by printing methods such as silk screen, gravure, offset printing, etc. can be cited.

[0111] Next, the frame portion 700 forming the lead line of the first electrode 20 or the second electrode 40 is described. The capacitance detection device 1 preferably does not have the frame portion 700 in any of the two directions orthogonal to each other around the sensing portion 600 of the first electrode 20 or the second electrode 40 (see Fig.21 ). If space is required for setting up a detour wiring in the two directions of the upper or lower direction and the right or left orthogonal to the sensing part 600, the shear force 60 cannot be measured in the area where the detour wiring is formed, so the length of the measurable range is limited. On the other hand, if there is no frame portion 700 in any of the two directions orthogonal to the sensing part 600 around the first electrode 20 or the second electrode 40 of the capacitance detection device 1, if a plurality of capacitance detection devices 1 are arranged and joined to form a long strip, the length of the measurable range can be infinitely extended.

[0112] If the sensing portion 600 can be extended to a desired length, the following effects can be achieved, for example: the pressure caused by the subtle unevenness of various parts of the tire, the degree of deviation in the shear force value, the change in the shear force 60 when the tire is accelerated or decelerated, and other measurements that were previously difficult to make can be easily detected. The method of making the frame portion 700 not exist on the upper and lower sides of the sensing portion 600 is not particularly limited, and for example, a method of slightly offsetting the positions of the first electrode 20 and the second electrode 40 and the positions of the detour wiring 250 and the detour wiring 450 and forming them in parallel patterns can be cited (see Fig.21 It should be noted that, when the accuracy and resolution of the measurement value required by the shear force 60 become higher and the detour wiring 250 and the detour wiring 450 must be made larger and thinner, a frame portion 700 can be provided on the left and right sides of the sensing portion 600 to separate the detour wiring 250 and the detour wiring 450 from each other to the left and right, thereby increasing the interval between each detour wiring.

[0113] Furthermore, by bending a portion of the detour wiring 250 and the detour wiring 450 near the first electrode 20 and the second electrode 40 at a right angle, the length of the detour wiring is substantially extended, thereby reducing the number of the detour wiring 250 and the detour wiring 450 by about half. As a result, the degree of freedom of the line width of the detour wiring 250 and the detour wiring 450 is increased, and the first electrode 20 and the second electrode 40 can be further miniaturized, thereby improving the accuracy and resolution of the measured value of the shear force 60. In addition, when a plurality of capacitance detection devices 1 are arranged and joined, in order to prevent the capacitance detection device 1 from moving and shifting, a convex portion 1200 and a concave portion 1300 (see FIG. 1 ) which are in the relationship between a key and a keyhole can also be provided on a portion of the capacitance detection device 1. Fig. 22 ).

[0114] If the convex part 1200 and the concave part 1300 are firmly fitted together, a plurality of capacitance detection devices 1 can play the same function as one integrated long capacitance detection device 1. The convex part 1200 and the concave part 1300 can be formed in the frame part 700 or in the sensor part 600. In addition, the shapes of the convex part 1200 and the concave part 1300 can be any shapes as long as they form a relationship between a key and a keyhole without falling off.

[0115] In addition to being applicable to tire driving tests, the above-mentioned strip capacitance detection device 1 can also be applied to various uses, such as measuring the shear force 60 applied to the sole surface when a person walks or runs, measuring the force exerted on the ground by a golf ball in a golf putter, the force exerted by a bowling ball when traveling on the lane, the force exerted when a person traces the display surface of an IT device with a fingertip, and the force exerted on the track when a train is traveling. For example, when a person walks or runs, the parts in contact with the ground surface are dispersed, and the walking stride and running stride vary from person to person. Even for the same person, the walking stride and running stride at the beginning and end of walking or running are different. Therefore, if the sensing portion 600 is formed on the entire surface of the strip, any walking stride or running stride can be measured, so the above-mentioned strip capacitance detection device 1 is highly useful.

[0116] It should be noted that when the capacitance detection device 1 is repeatedly subjected to very severe tests such as tire driving tests, the protective layer 50 on the surface is worn, or the second electrode 40 is damaged and becomes unusable. Each time, other capacitance detection devices need to be prepared, which has the problem of significantly increased costs from the standpoint of the tester. Therefore, it is possible to make it possible to disassemble all or part of the substrate 10 of the worn protective layer 50, the damaged insulating layer 30 of the second electrode 40, and the damaged first electrode 20, and to replace them appropriately for use. The term "disassembly" here means that they can be separated separately as long as certain means are used, and the means, labor used for disassembly, and time are not limited. In addition, even if a part of the layer is separated and not completely disassembled, the layer is deemed to be disassembled if the disassembled layer has its original function.

[0117] The removable protective layer 50 is preferably a laminated structure composed of multiple layers, and the protective layer 50 composed of only the base material 51 and the layer 71 composed of the self-adsorbing paste and the micro-suction cups can be removed and replaced (see Fig.23 ). With this configuration, it is very easy to remove and replace only a portion of the worn protective layer 50 from the capacitance detection device 1 (see Fig.23 ), which has the advantage of significantly reducing costs from the experimenter's point of view.

[0118] As the material of the self-adsorbing paste, in addition to two-component curing type urethane resin composed of polyol and polyisocyanate crosslinking agent, styrene butadiene latex, butadiene rubber, nitrile rubber, isoprene rubber, chloroprene rubber and other synthetic rubber resins, natural rubber resins, acrylic resins, silicone resins, etc. can also be mentioned. The method for forming the self-adsorbing paste layer is not particularly limited, for example, it can be applied using a general printing method such as offset plate and screen, a general coating machine such as lip coater and reverse coater, and it is preferably formed to a thickness of 10 to 500 μm.

[0119] The micro suction cup has the property of pressure-sensitive adsorption if the surface to which it is pasted is smooth. Moreover, it can be easily peeled off by hand and will not be sticky like an adhesive. The micro suction cup is preferably formed with suction cup-shaped micropores of a size of 1 to 500 μm at a ratio of 1,000 to 100,000 per 1 square centimeter. If the size of the suction cup is less than 2 μm, the adsorption effect is generated by the air pressure difference by softly adsorbing on the contact surface. In the case where the average size of the suction cup-shaped micropores is less than 1 μm and only 1,000 are formed per 1 square centimeter, and in the case where the average size of the suction cup-shaped micropores is greater than 500 μm and more than 100,000 are formed per 1 square centimeter, the adsorption force is sometimes reduced. As a method for forming a micro suction cup, air can be mechanically blown into a synthetic resin emulsion to generate countless fine bubbles, and a foamy synthetic resin emulsion can be made, which is applied by a coater or spraying to remove the solvent and form it.

[0120] Explanation of symbols

[0121] 1: Capacitance detection device, 5: Independent AC drive circuit, 10: Substrate, 20: First electrode, 21: Lower first electrode, 22: Upper first electrode, 25, 26, 27: Each electrode of the first electrode, 30, 31, 32: Insulating layer, 40, 45, 46: Second electrode, 41, 401: Lower second electrode, 42, 402: Upper second electrode, 45, 46, 47: Each electrode of the second electrode, 50: Protective layer, 51: Base material of the protective layer, 60: Shear force, 65: Shear Component of force in the X-axis direction, 66: Component of shear force in the Y-axis direction, 70: Countersunk unevenness, 71: Layer composed of self-adhesive paste and micro suction cups, 80: Conductive particles, 100: Capacitance detection device group, 110: Driving circuit, 120: Processing unit, 130: Signal conversion unit, 250, 450: Detour wiring, 300: Bubble size, 600: Sensing unit, 700: Frame unit, 800: Temperature sensor, 900: Temperature detection electrode, 1200: Convexity, 130 0: concave portion, S1: region where a portion of the island pattern of the first electrode overlaps with a portion of the pattern of the upper second electrode when viewed from above, S2: region where a portion of the island pattern of the first electrode overlaps with a portion of the pattern of the lower second electrode when viewed from above, S1′: region capable of detecting the capacitance value increased between the first electrode and the upper second electrode as a result of applying a component force in the X-axis direction from the right to the left on the paper, S2′: region capable of detecting the capacitance value increased between the first electrode and the lower second electrode as a result of applying a component force in the Y-axis direction from the upper to the lower on the paper, t20: average distance in the thickness direction between the first electrode of the island pattern and the lower second electrode, t40: average distance in the thickness direction between the first electrode of the island pattern and the upper second electrode, d20: distance in the short side direction of the first electrode when viewed from above, and is the distance in the pattern direction of the lower second electrode, d40: close distance between the ends of the intersection where the upper second electrode and the lower second electrode intersect when viewed from above, and is the distance in the pattern direction of the upper second electrode.

Claims

1. A capacitance detection device, comprising a first electrode, an insulating layer formed on the first electrode, and a second electrode formed on the insulating layer, The capacitance detection device is capable of calculating the shear force applied from the upper portion of the second electrode, The first electrode is a two-layer structure consisting of a lower first electrode and an upper first electrode with an insulating film interposed therebetween, and the second electrode is a two-layer structure consisting of a lower second electrode and an upper second electrode with an insulating film interposed therebetween. The lower first electrode and the lower second electrode are linear patterns extending along the X direction, and the upper first electrode and the upper second electrode are linear patterns extending along the Y direction, The X direction and the Y direction are perpendicular to each other. The insulating layer is composed of multiple layers in sequence, and the multiple insulating layers are composed of multiple foams with different bubble sizes; or The insulating layer is a multi-layer structure composed of foamed bodies of the same material, which are continuous in sequence, and the insulating layer has layers whose material hardness or elastic modulus changes step by step in one direction; or, The insulating layer is composed of a single layer and is composed of a foamed body in which the cell concentration and cell size are changed stepwise to give layers.

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