Capacitive sensor

Abstract

According to the invention, the structure of forming a plurality of sensor elements in the same sheet shape can be simplified. A capacitive sensor (1) is provided with a dielectric layer (20), a ground layer (21), and a voltage application layer (22), and is provided with: a wiring section (11) in which the ground layer (21) and the voltage application layer (22) are laminated on the dielectric layer (20) so that positions in the lamination direction do not overlap each other; and a capacitor unit which is a portion extending from an end portion of the wiring unit (11) in the plane direction, and in which the ground layer (21) and the voltage application layer (22) are laminated with the dielectric layer (20) interposed therebetween.

Description

Technical Field

[0001] This invention relates to capacitive sensors. Background Technology

[0002] For example, capacitive sensors are known in torque sensors that detect the deformation in the direction of torsion applied to a tested object such as a rod. A capacitive sensor includes a capacitor portion formed by forming a pair of electrode layers on the surface of a dielectric layer. In a capacitive sensor used as a torque sensor, the capacitor portion detects the capacitance change caused by the torsion generated by the tested object (see, for example, Patent Documents 1 to 2).

[0003] (Existing technical literature) (Patent Documents) Patent Document 1: Japanese Patent No. 4242977 Patent Document 2: Japanese Patent No. 5907220 Summary of the Invention

[0004] The problem that the invention aims to solve However, when a capacitive sensor is mounted on a test object, such as a slender cylindrical rod, where the height-to-diameter ratio is high, if the components of the sensor (sensor elements) containing the capacitor overlap, the thickness of the overlapping sensor elements increases, and the capacitive sensor is more prone to wear and deterioration under external forces. Therefore, it is preferable to form a capacitive sensor such that, when mounted on the test object, the sensor elements do not overlap, and the capacitor extends in an inclined direction relative to the length direction of the test object.

[0005] On the other hand, in capacitive sensors, when multiple sensor elements are formed on the same chip, it is required to improve manufacturability by simplifying the stack-up structure of the sensor elements, or to improve the mounting capability to the object being detected by making the sensor elements thinner.

[0006] Taking the aforementioned problem as an example, the present invention aims to provide a capacitive sensor that simplifies the structure of forming multiple sensor elements on the same sheet.

[0007] Methods for solving problems To achieve the above objectives, the capacitive sensor of the present invention is a capacitive sensor having a dielectric layer, a first electrode layer, and a second electrode layer, and further comprising: a wiring portion, wherein the first electrode layer and the second electrode layer are stacked with the dielectric layer in such a way that their positions do not overlap in the stacking direction; and a capacitor portion, which is a portion extending from the end of the wiring portion in the surface direction, wherein the first electrode layer and the second electrode layer are stacked with the dielectric layer sandwiched between them.

[0008] In a capacitive sensor according to one embodiment of the present invention, multiple capacitor portions are provided relative to one wiring portion.

[0009] In a capacitive sensor according to one embodiment of the present invention, a plurality of said capacitive portions are arranged symmetrically about the wiring portion in the surface direction.

[0010] In a capacitive sensor according to one embodiment of the present invention, the capacitor portion extends at an angle from the end of the wiring portion in the surface direction.

[0011] In a capacitive sensor according to one embodiment of the present invention, in the wiring portion, the dielectric layer is stacked on one side with the first electrode layer and on the other side with the second electrode layer.

[0012] In a capacitive sensor according to one embodiment of the present invention, the capacitor is arranged at an angle relative to the length direction of the object being detected.

[0013] Invention Effects According to the capacitive sensor of the present invention, it is possible to simplify the structure of forming multiple sensor elements into the same sheet shape. Attached Figure Description

[0014] Figure 1 This is a top view schematically illustrating the structure of a capacitive sensor according to an embodiment of the present invention.

[0015] Figure 2 yes Figure 1 The diagram shows a cross-sectional view of the capacitive sensor.

[0016] Figure 3 yes Figure 1 The BB cross-sectional view of the capacitive sensor shown.

[0017] Figure 4 It means Figure 1 A top view of the dielectric layer in the capacitive sensor shown.

[0018] Figure 5 It means Figure 1 A top view of the ground plane in the capacitive sensor shown.

[0019] Figure 6 It means Figure 1 A top view of the voltage application layer in the capacitive sensor shown.

[0020] Figure 7 It means Figure 1 A top view of the insulating layer in the capacitive sensor shown.

[0021] Figure 8 It means and Figure 1 The diagram shows a schematic of the equivalent capacitor of a capacitive sensor.

[0022] Figure 9 It means to use Figure 1 The diagram shows an example of a capacitance measurement circuit for a capacitive sensor.

[0023] Figure 10 It means to Figure 1 The diagram shows the capacitor section of a capacitive sensor mounted on the object being detected.

[0024] Figure 11 It means to Figure 1 Another schematic diagram of the capacitor section of the capacitive sensor in the state of being mounted on the object being detected. Detailed Implementation

[0025] In the following description, the capacitive sensor 1 according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0026] Figure 1 This is a top view schematically illustrating the structure of the capacitive sensor 1 according to an embodiment of the present invention. Figure 2 This is a cross-sectional view of capacitive sensor 1 (AA). Figure 3 This is a cross-sectional view of BB in capacitive sensor 1. Figure 2 This is a cross-sectional view showing the layer structure of the wiring section 11 in the capacitive sensor 1. Figure 3 This is a cross-sectional view showing the layer structure of the capacitor section 12 in the capacitive sensor 1.

[0027] In the following description, capacitive sensor 1 will be... Figure 1 The horizontal direction in the top view shown Figure 2 The horizontal direction in the sectional view shown is defined as the x-axis direction, and the direction orthogonal to the x-axis is... Figure 1 The vertical direction in the top view shown ( Figure 2 The direction that runs through the attached diagram is defined as the y-axis direction, and the direction orthogonal to the x-axis and y-axis is... Figure 1 The direction through the attached figure in the top view shown ( Figure 2 The longitudinal direction (in this context) is defined as the z-axis direction (height direction, stacking direction). In the following description, in... Figure 1 In the diagram, the direction pointed to by the arrows on the x, y, and z axes is designated as the "+" direction, and the direction opposite to the "+" direction is designated as the "-" direction. In the following explanation, the direction of the plane perpendicular to the stacking direction, i.e., the xy-plane, is referred to as the surface direction. Furthermore, in the following explanation, Figure 1The planes shown in the top view are all surfaces, and the planes opposite to the surfaces are the back faces. Based on the above definition, Figure 2 The sectional view shown is an xz sectional view of the capacitive sensor 1. Furthermore, in the following description, unless otherwise specified, all sectional views of the capacitive sensor 1 are xz sectional views.

[0028] like Figure 1 , 2 As shown in Figure 3, the capacitive sensor 1 according to this embodiment includes a dielectric layer 20, a ground layer 21 serving as a first electrode layer, a voltage application layer 22 serving as a second electrode layer, and an insulating layer 23. The capacitive sensor 1 has a wiring portion 11 and a capacitor portion 12. The wiring portion 11 is stacked with the dielectric layer 20 inside the insulating layer 23 such that the ground layer 21 and the voltage application layer 22 do not overlap in the stacking direction. The capacitor portion 12 is a portion extending from the end 111 in the surface direction of the wiring portion 11. In the capacitor portion 12, the ground layer 21 and the voltage application layer 22 are stacked inside the insulating layer 23, sandwiching the dielectric layer 20. The structure and operation of the capacitive sensor 1 will be described in detail below.

[0029] [Structure of wiring section and capacitor section] like Figure 1 As shown, in the capacitive sensor 1, a plurality of capacitor sections 12 are provided at the end 111 of the wiring section 11, relative to a wiring section 11. Figure 1 In the diagram, the dashed lines are provided to indicate the boundary between the wiring portion 11 and the capacitor portion 12. Specifically, the capacitor portion 12 extends outward from the left-right end 111 of the wiring portion 11, i.e., away from the wiring portion 11. In the capacitive sensor 1, the wiring portion 11 and the capacitor portion 12 are integrally formed.

[0030] Multiple capacitor sections 12 are arranged in the wiring section 11, for example, spaced at predetermined intervals in the planar direction (like comb teeth in the y-axis direction). Figure 1 The capacitors 12 are located at the ends 111 on both sides in the left and right directions. In the following description, the portion of the plurality of capacitors 12 located on the left side relative to the wiring portion 11 is also referred to as the first capacitor 12L. Furthermore, the portion of the plurality of capacitors 12 located on the right side relative to the wiring portion 11 is also referred to as the second capacitor 12R. The plurality of capacitors 12 may, for example, be arranged symmetrically with the wiring portion 11 as the center in the surface direction of the capacitive sensor 1. The plurality of capacitors 12 may also extend from the ends 111 in the surface direction of the wiring portion 11 at a predetermined angle. Figure 1 In the capacitor section 12, for example, the first capacitor section 12L extends along the -x-axis direction and the y-axis direction, and similarly, the second capacitor section 12R extends along the x-axis direction and the y-axis direction.

[0031] Furthermore, the arrangement of the capacitor sections 12 is not limited to a symmetrical arrangement centered on the wiring section 11; the spacing and number of capacitor sections 12 can also differ from left to right. Moreover, the spacing between the capacitor sections 12 can be non-fixed. Additionally, in the capacitive sensor 1, the number of capacitor sections 12 is not particularly limited. Furthermore, the angle between the end 111 of the wiring section 11 and the capacitor section 12 is not particularly limited. Furthermore, there can be locations where the angle between the wiring section 11 and the capacitor section 12 varies.

[0032] [Structure of dielectric layer, ground layer, voltage application layer, and insulating layer] Figure 4 This is a top view showing the dielectric layer 20 in the capacitive sensor 1. Figure 5 This is a top view showing the ground plane 21 in the capacitive sensor 1. Figure 6 This is a top view showing the voltage application layer 22 in the capacitive sensor 1. Figure 7 This is a top view showing the insulating layer 23 in the capacitive sensor 1. Figure 8 This is a schematic diagram representing a capacitor 3 that is equivalent to a capacitive sensor 1.

[0033] Reference Figures 4 to 8 The structure of the dielectric layer 20, ground layer 21, voltage application layer 22 and insulating layer 23 in the capacitive sensor 1 will be described.

[0034] Dielectric layer 20 has Figure 8 The function of the dielectric 30 in the capacitor 3 shown. As described above, the dielectric layer 20 is stacked with the ground layer 21 and the voltage application layer 22 inside the area surrounded by the insulating layer 23 in both the wiring portion 11 and the capacitor portion 12. Therefore, as Figure 4 As shown, the planar shape of the dielectric layer 20 has the same as... Figure 1 The capacitive sensors 1 shown have the same or substantially the same planar shape. The dielectric layer 20 has a first dielectric portion 201 located in the wiring portion 11 of the capacitive sensor 1 and a second dielectric portion 202 located in the capacitor portion 12.

[0035] The dielectric layer 20 is a sheet-like component, wherein the first dielectric portion 201 and the second dielectric portion 202 are integrally formed by an elastomer composition. The dielectric layer 20 is reversibly deformable by changing the area of ​​its surface and back surface. Furthermore, the dielectric layer 20 has a relatively large permittivity, for example, 5 or higher (measurement frequency 100Hz). Examples of elastomer compositions include compositions containing an elastomer and other arbitrary components such as dielectric particles as desired. Examples of elastomers include natural rubber, isoprene rubber, nitrile rubber (NBR), ethylene propylene diene monomer (EPDM), styrene-butadiene rubber (SBR), butadiene rubber (BR), chloroprene rubber (CR), silicone rubber, fluororubber, acrylic rubber, hydrogenated nitrile rubber, and urethane rubber. These can be used alone or in combination of two or more.

[0036] Ground layer 21 has Figure 8 The function of the negative electrode 31 in the capacitor 3 shown. The voltage application layer 22 has Figure 8 The function of the positive electrode 32 in the capacitor 3 shown is illustrated. As described above, the ground layer 21 and the voltage application layer 22 overlap in the capacitor section 12. However, in the wiring section 11, the ground layer 21 and the voltage application layer 22 do not overlap in the height direction and are arranged at different positions in the planar direction. Therefore, as... Figure 5 As shown, in the grounding layer 21, the planar shape of the portion constituting the wiring portion 11, namely the first grounding portion 211, is similar to... Figure 1 The wiring portion 11 in the shown capacitive sensor 1 has a different planar shape, being narrow in width in the left-right direction. On the other hand, in the ground layer 21, the portion constituting the capacitor portion 12, namely the second ground portion 212, has a planar shape that is different from... Figure 1 The capacitive parts 12 in the capacitive sensor 1 shown have the same or approximately the same planar shape.

[0037] To prevent the voltage application layer 22 from overlapping with the ground layer 21 at the location constituting the wiring portion 11, such as Figure 6 As shown, the part constituting the wiring section 11 is divided into a first component 22L (viewed from the left) and a second component 22R (viewed from the right).

[0038] In the first component 22L of the voltage application layer 22, the portion constituting the wiring portion 11, namely the first voltage application portion 221L, is located in Figure 5 The left side of the first grounding portion 211 of the grounding layer 21 shown has a shape that is not repeated from the first grounding portion 211. In other words, the first voltage application portion 221L has a shape that is similar to the first grounding portion 211. Figure 2The planar shape corresponds to the left side portion of the voltage application layer 22 in the wiring section 11. On the other hand, in the first constitutive section 22L of the voltage application layer 22, the planar shape of the portion constituting the capacitor section 12, i.e., the second voltage application section 222, has a shape similar to that of the left side portion of the voltage application layer 22. Figure 1 The capacitive parts 12 in the capacitive sensor 1 shown have the same or approximately the same planar shape.

[0039] In the second component 22R of the voltage application layer 22, the portion constituting the wiring portion 11, namely the first voltage application portion 221R, is located in Figure 5 The right side of the first grounding portion 211 of the grounding layer 21 shown has a shape that is not repeated from the first grounding portion 211. In other words, the first voltage application portion 221R has a shape that is similar to the first grounding portion 211. Figure 2 The planar shape corresponds to the right side portion of the voltage application layer 22 in the wiring section 11. On the other hand, in the second constituent section 22R of the voltage application layer 22, the planar shape of the portion constituting the capacitor section 12, i.e., the second voltage application section 222, has a shape similar to that of the right side portion of the voltage application layer 22. Figure 1 The capacitive parts 12 in the capacitive sensor 1 shown have the same or approximately the same planar shape.

[0040] The grounding layer 21 and the voltage application layer 22 are, for example, composed of a substance containing conductive materials such as carbon black, carbon nanotubes, silver nanoparticles, or other conductive particles in the above-mentioned elastomer composition.

[0041] Insulating layer 23 is disposed on the outside of ground layer 21, dielectric layer 20, and voltage application layer 22 on both sides of wiring portion 11 and capacitor portion 12. Therefore, as Figure 7 As shown, the planar shape of the insulating layer 23 has the same as... Figure 1 The capacitive sensors 1 shown have the same or substantially the same planar shape. Furthermore, the insulating layer 23 covers the upper and lower surfaces and sides of the ground layer 21, dielectric layer 20, and voltage application layer 22 in both the wiring portion 11 and the capacitor portion 12. The insulating layer 23 has a first insulating portion 231 located in the wiring portion 11 of the capacitive sensor 1 and a second insulating portion 232 located in the capacitor portion 12.

[0042] The insulating layer 23 provides electrical insulation between the grounding layer 21 and the external environment. Furthermore, the insulating layer 23 improves the strength and durability of the capacitive sensor 1. The insulating layer 23 can be made of the same elastomer composition or the same material constituting the dielectric layer 20.

[0043] Next, the configuration of each layer constituting the wiring section 11 and the capacitor section 12 will be described. For example... Figure 2As shown, for the wiring section 11 in the capacitive sensor 1, in the region surrounded by the insulating layer 23 disposed at the upper and lower ends and the sides, the ground layer 21 and the voltage application layer 22 are configured not to overlap in the height direction, i.e., in the z-axis direction. In other words, as Figure 5 , 6 As shown, in the wiring section 11, the first ground portion 211 of the ground layer 21 and the first voltage application portions 221L and 221R of the voltage application layer 22 are arranged at different positions in the planar direction. In the wiring section 11, a portion of the first dielectric portion 201 of the dielectric layer 20 overlaps with the first ground portion 211 of the ground layer 21 in the height direction. Furthermore, another portion of the first dielectric portion 201 overlaps with the first voltage application portions 221L and 221R of the voltage application layer 22 in the height direction. In other words, in the wiring section 11, a portion of the first dielectric portion 201 of the dielectric layer 20 is adjacent to the first ground portion 211 of the ground layer 21 in the planar direction, while other portions are adjacent to the first voltage application portions 221L and 221R of the voltage application layer 22.

[0044] In the wiring section 11, a ground layer 21 and an insulating layer 23 are stacked on one surface, i.e., on the back surface 204, of the first dielectric portion 201 of the dielectric layer 20. Specifically, in the wiring section 11, the central portion 204a of the back surface 204 of the first dielectric portion 201 of the dielectric layer 20 in the planar direction is stacked opposite to the surface 213 of the first ground portion 211 of the ground layer 21. Furthermore, in the wiring section 11, the outer peripheral portion 204b of the back surface 204 of the first dielectric portion 201 of the dielectric layer 20 in the planar direction is stacked opposite to the surface 233 of the first insulating portion 231 of the insulating layer 23.

[0045] In the wiring section 11, a voltage application layer 22 and an insulating layer 23 are stacked on another surface of the dielectric layer 20, namely surface 203. Specifically, in the wiring section 11, the central portion 203a of the surface 203 of the first dielectric portion 201 of the dielectric layer 20 in the planar direction is stacked opposite to the back surface 234 of the first insulating portion 231 of the insulating layer 23. Furthermore, in the wiring section 11, the outer peripheral portion 203b of the surface 203 of the first dielectric portion 201 of the dielectric layer 20 in the planar direction is stacked opposite to the back surface 224 of the first voltage application portion 221 of the voltage application layer 22.

[0046] In the wiring section 11, the back surface 214 of the first grounding section 211 is stacked opposite to the surface 233 of the first insulating section 231. Furthermore, in the wiring section 11, the surface 223 of the first voltage applying sections 221L and 221R is opposite to the back surface 234 of the first insulating section 231.

[0047] like Figure 3As shown, the capacitor section 12 in the capacitive sensor 1 differs from the wiring section 11 described above. In the region surrounded by insulating layers 23 disposed at the upper and lower ends and the sides, a ground layer 21, a dielectric layer 20, and a voltage application layer 22 are stacked sequentially from bottom to top in the height direction, i.e., from the -z-axis direction to the +z-axis direction in the z-axis direction. That is, in the region of the capacitor section 12 surrounded by insulating layers 23, the second ground portion 212 of the ground layer 21, the second dielectric portion 202 of the dielectric layer 20, and the second voltage application portion 222 of the voltage application layer 22 are stacked overlappingly. Specifically, the surface 233 of the second insulating portion 232 of the insulating layer 23 faces the back surface 214 of the second ground portion 212 of the ground layer 21. The surface 213 of the second ground portion 212 faces the back surface 204 of the second dielectric portion 202 of the dielectric layer 20. The surface 203 of the second dielectric portion 202 faces the back surface 224 of the second voltage application portion 222 of the voltage application layer 22. The surface 223 of the second voltage application part 222 faces the back surface 234 of the second insulation part 232.

[0048] The capacitive sensor 1 can be manufactured, for example, by the following steps. The capacitive sensor 1 can be manufactured by performing the following steps sequentially from the bottom: step (1) of making an insulating layer 23, step (2) of coating an elastomer composition onto the insulating layer 23 and making a ground layer 21, step (3) of coating an elastomer composition onto the ground layer 21 and making a dielectric layer 20, step (4) of coating an elastomer composition onto the dielectric layer 20 and making a voltage application layer 22, and step (5) of making an insulating layer 23 on the voltage application layer 22. In the above steps, for example, the ground layer 21 and voltage application layer 22 made in steps (2) and (4) have different stacking structures of the wiring portion 11 and the capacitor portion 12. Therefore, the layers can be made by masking the areas where no layers are formed according to their respective shapes. The layers can be made by appropriate methods such as spray screen printing or inkjet printing.

[0049] [Operation of a capacitive sensor] Next, the operation of the capacitive sensor 1 having the structure described above will be explained.

[0050] Figure 9 This is a schematic diagram illustrating an example of a capacitance measurement circuit 8 using a capacitive sensor 1. For example... Figure 9 As shown, the capacitance measurement circuit 8 consists of a capacitance sensor 1 and a control IC (Integrated Circuit) 9.

[0051] In addition to the structure of the capacitive sensor 1 described above, the capacitive sensor 1 also includes a negative electrode portion 216 extending from the ground layer 21, a positive electrode portion 226 extending from the back surface 224 of the voltage application layer 22L, and a positive electrode portion 227 extending from the back surface 224 of the voltage application layer 22R. Furthermore, the negative electrode portion 216 and the positive electrode portions 226 and 227 are not limited to those extending from the ground layer 21. Figure 9 The example shown is an extended form of the capacitive sensor 1, which can also be connected via a connector for a thin substrate.

[0052] The control IC9 has I / O (Input / Output) ports 4 and 6 and a ground port 5. I / O ports 4 and 6 are electrically connected to the positive electrode sections 226 and 227. Ground port 5 is electrically connected to the negative electrode section 216. Alternatively, in the capacitance measurement circuit 8, a switching circuit such as a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) can be provided between the capacitive sensor 1 and the control IC9.

[0053] Figure 10 This is a schematic diagram showing the capacitive sensor 1 installed on the object being detected 7. Figure 10 This is a diagram showing the capacitive sensor 1 mounted on the object being tested 7, viewed from the side where the wiring section 11 is provided. Figure 11 This is another schematic diagram showing the capacitive sensor 1 installed on the object being detected 7. Figure 11 This is a diagram showing the capacitive sensor 1 mounted on the object being tested 7, viewed from the front end of the capacitor section 12.

[0054] like Figure 10 as well as Figure 11 As shown, the capacitive sensor 1 is mounted on the surface of the object 7 to detect twisting that occurs on the object 7, such as an elongated round rod. Specifically, the capacitive sensor 1 is configured such that the capacitor portion 12 is inclined (at an angle) relative to the length direction, which is the axial direction of the object 7, and the wiring portion 11 is parallel to the length direction of the object 7. The capacitive sensor 1 transmits signals from... Figure 9 The I / O ports 4 and 6 of the control IC9 in the capacitance measurement circuit 8 shown are charged by applying voltage and the distortion of the tested object 7 is measured.

[0055] Capacitive sensor 1 Figure 10 as well as Figure 11As shown, the capacitor section 12 is mounted at an angle relative to the axis of the object being measured 7 for measurement. In the capacitive sensor 1, the wiring section 11 and the capacitor section 12, which extends from the end 111 of the wiring section 11 in the planar direction and detects twist, are provided at different positions in the planar direction. Therefore, by using the capacitive sensor 1 and mounting the capacitor section 12 at an angle relative to the axis of the object being measured 7, the noise component of the wiring section 11 is not included in the detected signal, thus enabling the detection of high-precision twist (torque).

[0056] Multiple capacitor sections 12 of the capacitive sensor 1 extend outward from their respective ends 111 in the left and right directions of the wiring section 11. In a right-hand (R) twist, the capacitance value of the first capacitor section 12L increases more than that of the second capacitor section 12R; in a left-hand (L) twist, the capacitance value of the second capacitor section 12R increases more than that of the first capacitor section 12L. Therefore, by using the capacitive sensor 1, when detecting a twist generated by the detected object 7, the direction of the twist (whether it is a right-hand (R) or left-hand (L) twist relative to the rotation direction of the detected object 7) can be determined by comparing the capacitance values ​​of the first capacitor section 12L and the second capacitor section 12R.

[0057] By extending the capacitor portion 12 from the wiring portion 11 at an angle, the capacitive sensor 1 can prevent the components (sensor elements) of the sensor from overlapping when the height-to-diameter ratio of the detected object 7, such as a round rod, is high, thereby reducing the thickness of the sensor element and thus reducing wear and deterioration caused by external forces.

[0058] Furthermore, by using the capacitive sensor 1, the manufacturability can be improved by simplifying the stacked structure, or the installation on the object to be detected can be improved by making the sensor element thinner.

[0059] In the capacitive sensor 1, multiple capacitor sections 12 are provided opposite to a wiring section 11. This structure allows for the... Figure 10 as well as Figure 11 When the capacitive sensor 1 is mounted on the object to be tested, such as a round bar, as shown, the twist can be detected at different positions along the length of the object to be tested, thereby enabling more precise twist detection.

[0060] In the capacitive sensor 1, multiple capacitor sections 12 are arranged, specifically, the first capacitor section 12L and the second capacitor section 12R are symmetrically arranged in the planar direction with the wiring section 11 as the center. With this structure, the capacitive sensor 1 can detect torsion equally regardless of the direction of torsion relative to the rotation direction of the detected object 7.

[0061] In the capacitive sensor 1, the capacitor portion 12 extends at an angle from the end portion 111 in the planar direction of the wiring portion 11. Therefore, when mounted on a test object 7, such as a round rod, it is possible to detect differences in the torsion of the test object 7 caused by differences in its length direction. Furthermore, the angled extension of the capacitor portion 12 from the end portion 111 in the planar direction of the wiring portion 11 prevents the components (sensor elements) of the sensor from overlapping.

[0062] In the capacitor section 12 of the capacitive sensor 1, the dielectric layer 20 has a ground layer 21 stacked on one side, for example, the surface, and a voltage application layer 22 stacked on the other side, for example, the back side. Similarly, in the wiring section 11, the dielectric layer 20 has a ground layer 21 and an insulating layer 23 stacked on one side, and a voltage application layer 22 and an insulating layer 23 stacked on the other side, for example, the back side. As described above, the dielectric layer 20 differs in the layers stacked by the wiring section 11 and the capacitor section 12, thereby simplifying the stacking structure of the wiring section 11. This improves manufacturability, reduces the thickness of the stacking direction, and enhances the mounting capability to the object being detected 7.

[0063] In the capacitive sensor 1, the capacitor 12 is configured to have an angle relative to the length direction of the object being detected 7, thereby enabling reliable detection of torsion relative to the rotational direction of the object being detected 7.

[0064] Therefore, based on the capacitive sensor 1, it is possible to simplify the structure of forming multiple sensor elements into the same sheet shape.

[0065] Furthermore, those skilled in the art can make appropriate modifications to the present invention based on previously known insights. As long as such modifications still retain the structure of the present invention, they are naturally included within the scope of the present invention.

[0066] For example, in the capacitive sensor 1 described above, although an example of setting the first electrode layer as the ground layer 21 and the second electrode layer as the voltage application layer 22 has been described, it is also possible to set the first electrode layer as the voltage application layer 22 and the second electrode layer as the ground layer 21.

[0067] For example, in the capacitive sensor 1 described above, although an example of the insulating layer 23 covering the upper and lower surfaces and sides of the dielectric layer 20, the ground layer 21, and the voltage application layer 22 has been described, the insulating layer 23 may also only cover the upper and lower surfaces of the dielectric layer 20, the ground layer 21, and the voltage application layer 22.

[0068] Symbol Explanation 1: Capacitive sensor; 3: Capacitor; 4; 6: I / O (input / output) port; 5: Ground port; 7: Detected object; 8: Capacitance measurement circuit; 11: Wiring section; 12: Capacitor section; 12L: First capacitor section; 12R: Second capacitor section; 20: Dielectric layer; 21: Ground layer; 22: Voltage application layer; 22L: First component section; 22R: Second component section; 23: Insulating layer; 30: Dielectric; 31: Negative electrode; 32: Positive electrode; 111: End; 201: First dielectric section; 202: Second dielectric section; 203: Surface; 203a 203a: Central part; 204b: Outer peripheral side part; 204: Back side; 204a: Central part; 204b: Outer peripheral side part; 211: First grounding part; 212: Second grounding part; 213: Surface; 214: Back side; 216: Negative electrode part; 221: First voltage application part; 221L: First voltage application part; 221R: First voltage application part; 222: Second voltage application part; 223: Surface; 224: Back side; 226: Positive electrode part; 227: Positive electrode part; 231: First insulating part; 232: Second insulating part; 233: Surface; 234: Back side.

Claims

1. A capacitive sensor, characterized in that, have: Dielectric layer, first electrode layer and second electrode layer; And has: The wiring section, wherein the first electrode layer and the second electrode layer are stacked with the dielectric layer in such a way that their positions in the stacking direction do not overlap with each other; The capacitor portion is a portion extending from the end of the wiring portion in the surface direction, wherein the first electrode layer and the second electrode layer are stacked with the dielectric layer sandwiched between them.

2. The capacitive sensor according to claim 1, wherein, A plurality of capacitor sections are provided relative to one of the wiring sections.

3. The capacitive sensor according to claim 2, wherein, The plurality of said capacitor portions are arranged symmetrically about the wiring portion in the surface direction.

4. The capacitive sensor according to claim 1, wherein, The capacitor portion extends at an angle from the end of the wiring portion in the surface direction.

5. The capacitive sensor according to claim 1, wherein, In the wiring section, the dielectric layer has the first electrode layer stacked on one side and the second electrode layer stacked on the other side.

6. The capacitive sensor according to claim 1, wherein, The capacitor is configured at an angle relative to the length direction of the object being tested.

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