Electrode connection structure and electrode connection method

The electrode connection structure includes: a first base material; a first electrode layer and a second electrode layer that are located on the first base material; a second base material; a first fastening member and a second fastening member; and an insulating member, wherein the first fastening member includes: a shaft portion inserted in a first through hole penetrating the first electrode layer and the insulating member; and two clamping portions that clamp a periphery of the first through hole in each of the first electrode layer and the insulating member, and the second fastening member includes: a shaft portion inserted in a second through hole penetrating the second electrode layer and the insulating member; and two clamping portions that clamp a periphery of the second through hole in each of the second electrode layer and the insulating member.

BACKGROUND

1. Technical Field

The present disclosure relates to an electrode connection structure and the like for connecting a connection terminal to an electrode.

2. Description of the Related Art

Conventionally, an electrode connection structure for connecting a connection terminal to an electrode has been provided (see, for example, Japanese Unexamined Patent Application Publication No. 2000-28742 (Patent Literature (PTL) 1)). For example, in the electrode connection structure (that is, the electrode connection structure) in PTL 1, the connection terminal is electrically and mechanically connected to the base member on the surface of which the conductive cloth-like antenna electrodes are formed. Then, the cable is electrically and mechanically connected to the connection terminal. Here, in the connection between the base member and the connection terminal, the electrode portion, which is a part of the antenna electrodes protruding from the end of the base member, is folded back to the back surface of the base member, and the stacked portion made of three layers of the antenna electrode, the base member, and the electrode portion is elastically clamped to the connection terminal. Furthermore, the connection terminal has a pin portion inserted in a hole penetrating in the stacking direction of the stacked portion.

SUMMARY

However, the electrode connection structure according to PTL 1 can be improved upon.

In view of this, the present disclosure provides an electrode connection structure capable of improving upon the above related art.

An electrode connection structure according to an aspect of the present disclosure includes: a first base material; a first electrode layer and a second electrode layer that are located on one surface of the first base material; a second base material disposed on a surface opposite to the one surface of the first base material; a first fastening member that fastens one end of a first electric wire to the first base material and the second base material; a second fastening member that fastens one end of a second electric wire to the first base material and the second base material; and an insulating member, wherein the first fastening member includes: a first shaft portion inserted in a first through hole penetrating the first electrode layer, the first base material, the second base material, and the insulating member; and two first clamping portions disposed on the first shaft portion so as to clamp a periphery of the first through hole in each of the first electrode layer, the first base material, the second base material, and the insulating member in an axial direction of the first shaft portion, the second fastening member includes: a second shaft portion inserted in a second through hole penetrating the second electrode layer, the first base material, the second base material, and the insulating member; and two second clamping portions disposed on the second shaft portion so as to clamp a periphery of the second through hole in each of the second electrode layer, the first base material, the second base material, and the insulating member in an axial direction of the second shaft portion, the one end of the first electric wire is fixed to the first fastening member while being electrically connected to the first electrode layer, and the one end of the second electric wire is fixed to the second fastening member while being electrically connected to the second electrode layer.

It should be noted that these comprehensive or specific aspects may be implemented by any combination of systems, methods, or integrated circuits.

The electrode connection structure of the present disclosure is capable of improving upon the above related art.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In the electrode connection structure of PTL 1, there is a problem in that when a cable is pulled, the stacked portion and the like is likely to be damaged. For example, when a sensor having an electrode connection structure is attached to a steering wheel of a vehicle, when the cable is pulled, a local tension is generated in a region or the like of a part of the antenna electrode that is around the pin portion connected to the cable. As a result, the antenna electrode or the like may be cracked or damaged. Therefore, the present disclosure provides an electrode connection structure or the like that is less likely to be damaged.

An electrode connection structure according to an aspect of the present disclosure includes: a first base material; a first electrode layer and a second electrode layer that are located on one surface of the first base material; a second base material disposed on a surface opposite to the one surface of the first base material; a first fastening member that fastens one end of a first electric wire to the first base material and the second base material; a second fastening member that fastens one end of a second electric wire to the first base material and the second base material; and an insulating member, wherein the first fastening member includes: a first shaft portion inserted in a first through hole penetrating the first electrode layer, the first base material, the second base material, and the insulating member; and two first clamping portions disposed on the first shaft portion so as to clamp a periphery of the first through hole in each of the first electrode layer, the first base material, the second base material, and the insulating member in an axial direction of the first shaft portion, the second fastening member includes: a second shaft portion inserted in a second through hole penetrating the second electrode layer, the first base material, the second base material, and the insulating member; and two second clamping portions disposed on the second shaft portion so as to clamp a periphery of the second through hole in each of the second electrode layer, the first base material, the second base material, and the insulating member in an axial direction of the second shaft portion, the one end of the first electric wire is fixed to the first fastening member while being electrically connected to the first electrode layer, and the one end of the second electric wire is fixed to the second fastening member while being electrically connected to the second electrode layer. For example, the insulating member may be a resin sheet. Alternatively, the insulating member may be a rubber sheet. Alternatively, the insulating member may be a non-woven fabric. Alternatively, the insulating member may be a metal sheet having an insulating surface.

With this, the insulating member is clamped together with the first base material and the second base material by the two first clamping portions of the first fastening member and the two second clamping portions of the second fastening member, so that the mechanical connection strength of the electrode connection structure can be increased, and the electrode connection structure can be made less prone to damage. That is, the insulating member is clamped together with the first base material and the like by the two first clamping portions of the first fastening member fixed to one end (specifically, the cable terminal) of the first electric wire such as a cable. Furthermore, the insulating member is also clamped together with the first base material and the like by the two second clamping portions of the second fastening member fixed to one end (specifically, the cable terminal) of the second electric wire such as another cable. Therefore, for example, when a force is applied to the first shaft portion of the first fastening member fixed to one end of the first electric wire by pulling the first electric wire (for example, a cable), the insulating member receives the tensile stress. Here, since the insulating member is also clamped together with the first base material, the second base material and the like by the second fastening member, the first base material and the second base material are reinforced, and the insulating member can suppress the movement of the first shaft portion of the first fastening member fixed to one end of the insulating member. Even if the second electric wire is pulled, the insulating member can similarly suppress the movement of the second shaft portion of the second fastening member fixed to one end of the second electric wire. As a result, it is possible to suppress the periphery of the first through hole in the first electrode layer, the first base material, and the second base material from being torn by the first shaft portion. Similarly, it is possible to suppress the periphery of the second through hole in the second electrode layer, the first base material, and the second base material from being torn by the second shaft portion.

In addition, the insulating member may be disposed between the second base material and one of the two first clamping portions and between the second base material and one of the two second clamping portions.

With this, since the insulating member is disposed as a cushioning material between (i) the second base material and (ii) the first clamping portion and the second clamping portion, even if the second base material is strongly pressed by the first clamping portion and the second clamping portion clamping the second base material, the local pressure on the second base material can be relieved.

In addition, the electrode connection structure further includes: a first metal wire and a second metal wire each fixed to the second base material, the two first clamping portions clamp the first metal wire fixed to the second base material in the axial direction of the first shaft portion together with the first electrode layer, the first base material, the second base material, and the insulating member, and the two second clamping portions may clamp the second metal wire fixed to the second base material in the axial direction of the second shaft portion together with the second electrode layer, the first base material, the second base material, and the insulating member.

With this, since the first metal wire fixed to the second base material is clamped together with the first base material and the like by the first fastening member, the mechanical connection strength of the electrode connection structure can be further increased, and the electrode connection structure can be made less prone to damage. That is, the first metal wire fixed to the second base material is clamped by the two first clamping portions of the first fastening member fixed to one end (specifically, the cable terminal) of the first electric wire such as a cable. Therefore, for example, when a force is applied to the first shaft portion of the first fastening member fixed to one end of the first electric wire by pulling the first electric wire (for example, a cable), the first metal wire receives the tensile stress. Here, since the first metal wire is fixed to the second base material, it reinforces the second base material, and the first metal wire can suppress the movement of the first shaft portion of the first fastening member fixed to one end of the first electric wire. As a result, the periphery of the through hole in the first electrode layer, the first base material, and the second base material can be suppressed from being torn by the first shaft portion. In addition, similarly to the first metal wire, the second metal wire fixed to the second base material is also clamped together with the first base material and the like by the second fastening member. Therefore, even with this second metal wire, the mechanical connection strength of the electrode connection structure can be further increased, and the electrode connection structure can be made less prone to damage.

It should be noted that the first metal wire and the second metal wire may be the same metal wire or may be electrically insulated metal wires different from each other.

In addition, the first base material includes a first main base material and a first convex portion protruding from the first main base material, the second base material includes a second main base material facing the first main base material, and a second convex portion protruding from the second main base material and facing the first convex portion, each of the first electrode layer and the second electrode layer is disposed over a range including at least a part of the first main base material and at least a part of the first convex portion, the first shaft portion of the first fastening member is inserted in the first through hole penetrating the first electrode layer, the first convex portion, the second convex portion, and the insulating member, the second shaft portion of the second fastening member is inserted in the second through hole penetrating the second electrode layer, the first convex portion, the second convex portion, and the insulating member, and the first metal wire and the second metal wire may be fixed to the second main base material.

With this, since the first metal wire and the second metal wire are fixed to the second main base material, even if the first electric wire or the second electric wire is pulled, it is possible to suppress the first convex portion and the second convex portion from being torn from the first main base material and the second main base material.

In addition, each of the first metal wire and the second metal wire includes a substantially U-shaped folded-back portion, both ends of the folded-back portion are fixed to the second main base material, a central portion of the folded-back portion is fixed to the second convex portion, and the first shaft portion of the first fastening member or the second shaft portion of the second fastening member may be disposed inward of the folded-back portion.

With this, since the first shaft portion or the second shaft portion is disposed inward of the folded-back portion, even if a strong outward force is applied to the first shaft portion or the second shaft portion by pulling the first electric wire or the second electric wire, it can sufficiently withstand the force by the substantially U-shaped folded-back portion. As a result, the mechanical connection strength of the electrode connection structure can be further increased.

In addition, each of the first metal wire and the second metal wire having an electrically insulated surface may be a heater element that generates heat by a current flowing through the metal wire to warm the electrode connection structure.

With this, when the electrode connection structure is, for example, attached to a rim of a steering wheel, the rim can be warmed. As a result, the driver of the vehicle equipped with the steering wheel can comfortably grip the rim even when the inside of the vehicle is cold.

In addition, each of the first metal wire and the second metal wire having an electrically insulated surface may be a disturbance noise detection electrode that detects disturbance noise with respect to signals detected in the first electrode layer and the second electrode layer.

This allows the influence of disturbance noise to be suppressed and the measurement value based on the capacitance generated in the first electrode layer and the second electrode layer to be appropriately acquired.

In addition, one of the two first clamping portions clamps a conductive first non-woven fabric between the one of the two first clamping portions and the first electrode layer, and one of the two second clamping portions clamps a conductive second non-woven fabric between the one of the two second clamping portions and the second electrode layer.

With this, since the first non-woven fabric is disposed as a cushioning material between one of the two first clamping portions and the first electrode layer, the occurrence of damage such as cracks in the first electrode layer can be suppressed. In addition, since the first non-woven fabric is electrically conductive, it is possible to transmit the electric signal from the first electrode layer appropriately to the first electric wire such as a cable via the first non-woven fabric. Similarly to the first non-woven fabric, since the second non-woven fabric is disposed as a cushioning material, the occurrence of damage to the second electrode layer can be suppressed and it is possible to transmit the electric signal from the second electrode layer appropriately to the second electric wire.

In addition, an electrode connection structure according to another aspect of the present disclosure includes: a first base material; an electrode layer located on one surface of the first base material; a second base material disposed on a surface opposite to the one surface of the first base material; a metal wire fixed to the second base material; and a fastening member that fastens one end of an electric wire to the first base material and the second base material, wherein the fastening member includes: a shaft portion inserted in a through hole penetrating the electrode layer, the first base material and the second base material; and two clamping portions disposed on the shaft portion so as to clamp a periphery of the through hole in each of the electrode layer, the first base material, and the second base material in an axial direction of the shaft portion, the one end of the electric wire is fixed to the fastening member while being electrically connected to the electrode layer, and the two clamping portions clamp the metal wire fixed to the second base material in the axial direction together with the electrode layer, the first base material, and the second base material.

With this, since the metal wire fixed to the second base material is clamped by the two clamping portions of the fastening member together with the first base material and the like, the mechanical connection strength of the electrode connection structure can be increased, and the electrode connection structure can be made less prone to damage. That is, the metal wire fixed to the second base material is clamped by the two clamping portions of the fastening member fixed to one end (specifically, a cable terminal) of an electric wire such as a cable. Therefore, for example, when a force is applied to the shaft portion of the fastening member fixed to one end of the electric wire by pulling the electric wire (for example, the cable), the metal wire receives the tensile stress. Here, since the metal wire is fixed to the second base material, the second base material is reinforced, and the metal wire can suppress the movement of the shaft portion of the fastening member fixed to one end of the electric wire. As a result, it is possible to suppress the periphery of the through hole in the electrode layer, the first base material, and the second base material from being torn by the shaft portion.

In addition, the electrode connection structure may further include an insulating member disposed between the metal wire and one of the two clamping portions and clamped in the axial direction by the two clamping portions. For example, the insulating member may be a resin sheet. Alternatively, the insulating member may be a metal washer having a surface with an insulating property.

With this, since the insulating member is disposed as a cushioning material between the metal wire and one of the two clamping portions, even if the metal wire is strongly pressed by the clamping portions clamping the metal wire, the occurrence of damage of the metal wire can be suppressed. As a result, even if the metal wire is coated, it is possible to suppress the coating from peeling off.

In addition, the electrode connection structure may further include: a third fastening member that fastens one end of the third electric wire to the first base material and the second base material; and a banding member that bands at least one of the first electric wire or the second electric wire and the third electric wire. For example, the electrode connection structure further includes a metal wire fixed to the second base material, wherein the third fastening member may fasten the third electric wire to the first base material and the second base material by electrically and structurally connecting one end of the third electric wire to one end of the metal wire.

With this, at least one of the first electric wire or the second electric wire and the third electric wire are banded by the banding member. Therefore, even if the third electric wire is pulled, it is possible to suppress the pulling force from being transmitted to the third fastening member, and to transmit the pulling force to the first fastening member and the second fastening member that have high mechanical strength. As a result, it is possible to suppress the second base material from being torn by the third fastening member and the metal wire.

In addition, the electrode connection structure may further include another fastening member for fastening one end of another electric wire different from the electric wire to the first base material and the second base material; and a banding member that bands the electric wire and the other electric wire. For example, the other fastening member may fasten the other electric wire to the first base material and the second base material by electrically and structurally connecting one end of the other electric wire to one end of the metal wire.

With this, the electric wire and the other electric wire are banded by the banding member. Therefore, even if the other electric wire is pulled, it is possible to suppress the pulling force from being transmitted to the other fastening member, and to transmit the pulling force to the fastening member having high mechanical strength. As a result, it is possible to suppress the second base material from being torn by the other fastening member and the metal wire.

In addition, an electrode connection method according to one aspect of the present disclosure includes: disposing a second base material on a surface opposite to one surface of a first base material having the one surface on which a first electrode layer and a second electrode layer are formed; disposing an insulating member on the second base material; fastening one end of the first electric wire to the first base material and the second base material by a first fastening member having a first shaft portion and two first clamping portions disposed on the first shaft portion; and fastening one end of the second electric wire to the first base material and the second base material by a second fastening member having a second shaft portion and two second clamping portions disposed on the second shaft portion, the fastening by the first fastening member including: inserting the first shaft portion in a first through hole that penetrates the first electrode layer, the first base material, the second base material, and the insulating member; clamping a periphery of the first through hole in each of the first electrode layer, the first base material, the second base material, and the insulating member by the two first clamping portions in an axial direction of the first shaft portion; and fixing the one end of the first electric wire to the first fastening member while being electrically connected to the first electrode layer, the fastening by the second fastening member including: inserting the second shaft portion in a second through hole that penetrates the second electrode layer, the first base material, the second base material, and the insulating member; clamping a periphery of the second through hole in each of the second electrode layer, the first base material, the second base material, and the insulating member by the two second clamping portions in an axial direction of the second shaft portion; and fixing the one end of the first electric wire to the first fastening member while being electrically connected to the first electrode layer.

In addition, an electrode connecting method according to another aspect of the present disclosure includes: disposing a second base material on a surface opposite to one surface of a first base material having the one surface on which an electrode layer is formed; fixing a metal wire to the second base material; fastening one end of an electric wire to the first base material and the second base material by a fastening member having a shaft portion and two clamping portions disposed on the shaft portion, the fastening by the fastening member includes: inserting the shaft portion in a through hole penetrating the electrode layer, the first base material, and the second base material; clamping a periphery of the through hole in each of the electrode layer, the first base material, and the second base material by the two clamping portions in an axial direction of the shaft portion; and fixing the one end of the electric wire to the fastening member while being electrically connected to the electrode layer, wherein the two clamping portions clamp the metal wire fixed to the second base material in the axial direction together with the electrode layer, the first base material, and the second base material.

With this, the same working effect as the electrode connection structure described above can be obtained.

Hereinafter, embodiments will be specifically described with reference to the drawings.

It should be noted that each of the embodiments described below shows a comprehensive or specific example. Numerical values, shapes, materials, components, arrangement positions and connection forms of components elements, steps, order of steps, and the like shown in the following embodiments are examples, and are not intended to limit the present disclosure. In addition, among the components in the following embodiments, components not described in the independent claim showing the highest concept are described as arbitrary components.

In addition, each drawing is a schematic view, and is not necessarily strictly illustrated. In addition, in each drawing, the same reference numerals are given to the same component members. In addition, in the following embodiments, expressions such as a substantially T-shape are used. For example, substantially the same means not only being exactly the same, but also being substantially the same, that is, including an error of, for example, about several percent. In addition, substantially the same means being the same within a range in which the effect according to the present disclosure can be obtained. The same applies to other expressions using “substantially”.

FIG. 1is a diagram showing an example of a vehicle interior of a vehicle in which a grip sensor having an electrode connection structure according to the present embodiment is disposed.

Vehicle1includes steering wheel200, speaker301, and display device302such as a liquid crystal display. Speaker301and display device302are configured as an alerting device, for example.

Steering wheel200is for steering vehicle1. Steering wheel200includes ring-shaped rim210, substantially T-shaped spoke202integrally formed on the inner peripheral surface of rim210, and horn switch cover203covering a horn switch (not shown) disposed in the center of spoke202.

Grip sensor100is a device that detects a grip of steering wheel200by a hand, and is provided in steering wheel200of vehicle1as shown inFIG. 1. Specifically, grip sensor100includes sensor110embedded in rim210of steering wheel200, control circuit120that detects a grip based on a signal from sensor110, and harness130that electrically connects sensor110to control circuit120. Control circuit120is embedded in spoke202, for example. Such grip sensor100detects a grip of rim210of steering wheel200.

A part or all of sensor110in the present embodiment is configured as an electrode connection structure. In addition, sensor110includes at least one electrode. At this electrode, the capacitance changes depending on whether the driver of vehicle1is gripping rim210of steering wheel200or not. Control circuit120measures a value corresponding to the capacitance of the electrode, and detects the grip of rim210by the driver's hand based on the value. Then, when vehicle1is driven but the grip is not detected, control circuit120causes the alerting device to alert the driver. For example, speaker301of the alerting device alerts the driver with a warning sound or a voice. Display device302displays a warning message prompting the driver to firmly hold steering wheel200. This can reduce traffic accidents.

FIG. 2is a diagram showing an example of how to wrap sensor110around rim210in the present embodiment.

Sensor110is a sheet-shaped structure having elasticity, flexibility, and ductility as a whole, and is formed in a long shape.

It should be noted that in the present embodiment, the longitudinal direction of sensor110is referred to as the Y-axis direction, and the direction perpendicular to the Y-axis direction on the plane parallel to sensor110is referred to as the X-axis direction. In addition, one end side (left end side inFIG. 2) of sensor110in the Y-axis direction is referred to as a negative side, and the other end side (right end side inFIG. 2) is referred to as a positive side. Similarly, one end side (lower end side inFIG. 2) of sensor110in the X-axis direction is referred to as a negative side, and the other end side (upper end side inFIG. 2) is referred to as a positive side. Furthermore, the direction perpendicular to the plane of sensor110is referred to as the Z-axis direction. In addition, one side in the Z-axis direction (back side of the plane ofFIG. 2) is referred to as a negative side, and the other side in the Z-axis direction (front side of the plane ofFIG. 2) is referred to as a positive side.

Sensor110is attached to rim210of steering wheel200. At this time, sensor110is wrapped around rim210so that sensor110forms a ring. Then, both ends Ea and Eb of sensor110are disposed so as to substantially face each other.

FIG. 3Ais a front view of grip sensor100according to the present embodiment.FIG. 3Bis a rear view of grip sensor100according to the present embodiment.

For example, as shown inFIGS. 3A and 3B, sensor110includes first base material111, second base material112, four electrode layers113, four fastening members114, and two metal wires115.

First base material111is formed by a material having elasticity, flexibility, and ductility in a long sheet shape. For example, first base material111comprises synthetic resin such as polyethylene terephthalate (PET).

Each of four electrode layers113is formed on one surface, for example, the front surface of first base material111, as shown inFIG. 3A. It should be noted that the front surface is, for example, a surface on the positive side in the Z-axis direction of first base material111. These electrode layers113are formed on the front surface of first base material111by nickel plating, for example.

It should be noted that although sensor110has four electrode layers113in the present embodiment, the number of electrode layers113may be one, two, or three, or may be four or more. In addition, electrode layer113may have any form as long as it functions as an electrode. That is, electrode layer113may be a solid electrode, a sheet-shaped or plate-shaped electrode, a wiring pattern, or the like. In other words, the shape, number, array pattern and the like of electrode layers113shown inFIGS. 3A and 3Bare examples, and may have any shape, number, and array pattern.

In addition, first base material111may be separated into four portions. In this case, electrode layer113is formed on each of the four portions. Furthermore, electrode layer113may be formed not only on the respective surfaces of the four separated portions but also on the entire surface. In addition, when each of the four portions of first base material111is formed as a PET woven fabric, electrode layer113may be formed over the entire fibers of the woven fabric. In this case, first base material111on which electrode layer113is formed is configured as a conductive cloth.

As shown inFIG. 3B, second base material112is disposed on the surface opposite to the one surface of first base material111, that is, on the rear surface. Similar to first base material111, this second base material112is configured as a long mat made of a material (for example, polyethylene) having elasticity, flexibility, and ductility. First base material111and second base material112are, for example, stacked so that their peripheral edges coincide with each other when viewed from the front surface or the rear surface, and joined to each other by a tape having an adhesive layer such as a double-sided tape or the like, or an adhesive bond or an adhesive agent. It should be noted that a structure using a double-sided tape will be described in the following description.

Each of four fastening members114has a member for fastening one end (for example, a cable terminal) of cable116, which is an electric wire for electrically connecting to electrode layer113corresponding to fastening member114, to first base material111and second base material112. These fastening members114are, for example, rivets. It should be noted that fastening member114is not limited to a rivet, and may be a member including a bolt and a nut or may be another member as long as it can fasten first base material111and second base material112together. In addition, electrode layer113is electrically connected to control circuit120by fastening member114via cable116. It should be noted that as shown inFIGS. 3A and 3B, harness130is formed by banding a plurality of (here, four) cables116and metal wires115.

Each of two metal wires115is fixed to the surface of second base material112opposite to first base material111. For example, metal wires115are sewn to second base material112so that a zigzag pattern is formed. Metal wire115is, for example, a resin-coated conductive wire and is used as a heater element. That is, the surface of metal wire115is electrically insulated, and both ends of metal wire115are electrically connected to control circuit120. When control circuit120causes an electric current to flow through metal wire115, metal wire115generates heat. Due to this heat generation, metal wire115warms sensor110. As a result, rim210of steering wheel200can be warmed. Therefore, the driver of vehicle1can comfortably grip rim210even if the inside of the vehicle is cold.

The electrode connection structure in the present embodiment may be entire sensor110or a part of sensor110. The part of sensor110is, for example, a structure including fastening member114in sensor110and a periphery where fastening member114is disposed.

FIG. 4is a diagram showing an example of a cross section of rim210to which sensor110is attached.

Rim210includes cored bar201b, which is a metal annular core, and resin layer201acomprising urethane resin or the like, which covers cored bar201b.

Sensor110shown inFIGS. 3A and 3Bis wrapped around resin layer201aso that second base material112faces resin layer201a. As a result, each component of sensor110is arranged in the order of metal wire115, second base material112, first base material111, and electrode layer113from the resin layer201aside toward the outside. It should be noted that the surface of sensor110wrapped around in this manner on the electrode layer113side is covered with surface layer201ccomprising leather, wood, resin, or the like.

Electrode layer113disposed on rim210forms a capacitance between electrode layer113and cored bar201b. Here, when the part of rim210where electrode layer113is disposed is gripped by the driver's hand, capacitance is also formed between electrode layer113and the hand. Therefore, control circuit120can detect the grip of rim210by the hand from the signal output from electrode layer113according to the capacitance.

FIG. 5is an exploded perspective view of sensor110.

First base material111on which four electrode layers113are formed includes long first main base material111aand four first convex portions111bprotruding from first main base material111a. Specifically, each of four first convex portions111bis arranged along the Y-axis direction at substantially the center of the side of first main base material111aon the negative side in the X-axis direction, and protrudes on the negative side in the X-axis direction.

Each of four electrode layers113is formed in a range including a part of first main base material111aand at least a part of first convex portion111bcorresponding to electrode layer113. Furthermore, through hole105is formed in a portion where electrode layer113is formed in each of four first convex portions111b.

Second base material112includes second main base material112afacing first main base material111aand four second convex portions112bprotruding from second main base material112aand facing four respective first convex portions111b. Specifically, similar to four first convex portions111b, each of four second convex portions112bis arranged substantially in the center of the side of second main base112aon the negative side in the X-axis direction along the Y-axis direction, and protrudes on the negative side in the X-axis direction. Furthermore, through hole105is formed in each of four second convex portions112b.

First base material111and second base material112are stacked via a double-sided tape with through holes105formed in the respective base materials disposed to communicate with each other. At this time, the rear surface of first base material111, that is, the surface on which electrode layer113is not formed, and the rear surface of second base material112, that is, the surface on which metal wire115is not sewn, are joined by a double-sided tape. With this, first base material111and second base material112are bonded together. It should be noted that through hole105may be formed by drilling first base material111and second base material112after they are stacked via the double-sided tape.

Here, a set of first convex portion111bof first base material111on which electrode layer113is formed and second convex portion112bof second base material112that is joined to face first convex portion111bwill be referred to as electrode lead-out portion10below. That is, sensor110has four electrode lead-out portions10.

In the present embodiment, in order to electrically connect electrode layer113of electrode lead-out portion10to control circuit120for each of four electrode lead-out portions10, cable116that is an electric wire and cable terminal117connected to one end of cable116are used. Cable116is, for example, an insulation-coated copper wire. Cable terminal117is a ring-shaped (or round-shaped) crimp terminal. This cable terminal117is fastened to first base material111and second base material112by fastening member114. An electrically conductive non-woven fabric102and a pair of washers101are used for this fastening.

Electrically conductive non-woven fabric102is a non-woven fabric with electrical conductivity. For example, electrically conductive non-woven fabric102has elasticity, flexibility and ductility, and is formed by nickel-plating a synthetic resin non-woven fabric. In addition, through hole105is also formed in this electrically conductive non-woven fabric102.

Such electrically conductive non-woven fabric102is disposed for each of four electrode lead-out portions10. That is, electrically conductive non-woven fabric102is disposed so as to stack electrode layer113of electrode lead-out portion10such that respective through holes105of electrically conductive non-woven fabric102and electrode lead-out portion10communicate with each other.

Then, the pair of washers101is disposed so as to clamp electrode lead-out portion10and electrically conductive non-woven fabric102in the Z-axis direction with respect to each of four electrode lead-out portions10. It should be noted that washer101is made of metal and is formed by plating nickel on copper.

Furthermore, cable terminal117is disposed for each of four electrode lead-out portions10. That is, cable terminal117is disposed on the positive side in the Z-axis direction of washer101so that electrically conductive non-woven fabric102and washer101are clamped between cable terminal117and electrode layer113of electrode lead-out portion10. At this time, cable terminal117is disposed so that the hole of the ring of cable terminal117, the hole of the pair of washers101, and respective through holes105of electrically conductive non-woven fabric102and the electrode lead-out portion10communicate with each other.

Then, fastening member114is disposed for each of four electrode lead-out portions10. That is, the shaft of fastening member114(shaft portion114cdescribed later) is inserted in through hole105penetrating electrode layer113, first convex portion111b, and second convex portion112b. More specifically, fastening member114is inserted in the hole of the ring of cable terminal117, the hole of the pair of washers101, and respective through holes105of electrically conductive non-woven fabric102and electrode lead-out portion10from the positive side to the negative side in the Z-axis direction. Furthermore, the tip of the inserted fastening member114is crimped while protruding from washer101on the negative side in the Z-axis direction. That is, the crimping causes the tip of fastening member114to be plastically deformed and crushed.

With this, in each of four electrode lead-out portions10, cable terminal117, which is one end of the electric wire, is fixed to fastening member114while being electrically connected to electrode layer113of electrode lead-out portion10via electrically conductive non-woven fabric102and washer101. The electrode connecting structure in the present embodiment includes such electrode lead-out portion10, fastening member114corresponding to electrode lead-out portion10, electrically conductive non-woven fabric102, cable terminal117, a pair of washers101, and metal wire115.

FIG. 6is a diagram showing a central portion of sensor110. Specifically, (a) inFIG. 6shows a front-side center portion of sensor110, and (b) inFIG. 6shows a back-side center portion of sensor110.FIG. 7is a cross-sectional view showing a cross section taken along line A-A of sensor110shown in (a) inFIG. 6.

As shown inFIG. 7, fastening member114includes shaft portion114cand two clamping portions114aand114bdisposed on shaft portion114c. Shaft portion114cis inserted in through hole105of electrode lead-out portion10, that is, through hole105penetrating electrode layer113, first base material111, and second base material112. Two clamping portions114aand114bare disposed on shaft portion114cso as to clamp the periphery of through hole105in each of electrode layer113, first base material111, and second base material112in the axial direction of shaft portion114c. It should be noted that when fastening member114is a rivet, clamping portion114ais a head portion of the rivet, shaft portion114cis a body portion of the rivet, and clamping portion114bis a portion formed like a head portion by crimping the tip of the body portion. In addition, as shown inFIG. 7, first base material111and second base material112are joined by double-sided tape103.

Here, in electrode lead-out portion10in the present embodiment, clamping portions114aand114bof fastening member114clamp metal wire115fixed to second base material112in the Z-axis direction together with electrode layer113, first base material111, and second base material112, as shown inFIGS. 6 and 7. That is, clamping portions114aand114bclamp metal wire115sewn on second base material112together with electrode layer113, first base material111, and the like. In other words, fastening member114fastens metal wire115together with electrode layer113, first base material111, and the like.

With this, in the present embodiment, the mechanical connection strength of the electrode connection structure including electrode lead-out portion10can be increased. For example, when a force is applied to shaft portion114cof fastening member114fixed to cable terminal117by pulling cable116connected to cable terminal117, metal wire115receives the tensile stress. Therefore, since metal wire115is firmly fixed to entire second base material112as shown inFIG. 3B, second base material112is reinforced and the movement of shaft portion114cof fastening member114fixed to cable terminal117can be suppressed by metal wire115. As a result, the periphery of through hole105in electrode layer113, first base material111, and second base material112can be suppressed from being torn by shaft portion114c.

In addition, the part of metal wire115clamped by clamping portions114aand114bis on second convex portion112bas shown in (b) inFIG. 6. The other part of metal wire115is fixed to second main base material112aas shown in (b) inFIG. 6.

Therefore, since metal wire115is fixed to second main base material112a, even if cable116connected to cable terminal117is pulled, it is possible to suppress first convex portion111band second convex portion112bfrom being torn from first main base material111aand second main base material112a.

FIG. 8is a diagram showing an example of a part where metal wire115is clamped. Specifically,FIG. 8is an enlarged view of a part of metal wire115around clamping portion114bof fastening member114shown in (b) inFIG. 6.

As shown inFIG. 8, metal wire115in the present embodiment includes substantially U-shaped folded-back portion115a. Both ends of folded-back portion115aare fixed to second main base material112a. In addition, the central portion of folded-back portion115ais fixed to second convex portion112b. Then, shaft portion114cof fastening member114is disposed inward of folded-back portion115a. In addition, the central portion of folded-back portion115ais included in clamping portion114bof fastening member114.

With this, even if a strong force to the outside (for example, the negative side in the X-axis direction) is applied to shaft portion114cby pulling cable116, the electrode connection structure can sufficiently withstand the force due to substantially U-shaped folded-back portion115aof metal wire115. As a result, the mechanical connection strength of the electrode connection structure can be further increased.

FIG. 9is a diagram showing another example of a part where metal wire115is clamped.

As shown inFIG. 8, metal wire115in the present embodiment includes substantially U-shaped folded-back portion115a, but it may not include such folded-back portion115a. For example, the part where metal wire115is clamped may be formed in a substantially I-shape as shown inFIG. 9. Since even with such a shape, metal wire115reinforces second convex portion112band metal wire115is clamped by clamping portions114aand114b, the mechanical connection strength of the electrode connection structure can be increased.

FIG. 10is a diagram showing another example of a part where metal wire115is clamped.

Metal wire115in the present embodiment includes substantially U-shaped folded-back portion115aas shown inFIG. 8, but substantially U-shaped may be a shape having a narrowed upper portion as shown inFIG. 10, for example. That is, substantially U-shaped folded-back portion115ais defined to include the shape ofFIG. 10. Even with such a shape, the electrode connection structure can sufficiently withstand the force due to substantially U-shaped folded-back portion115aof metal wire115. As a result, the mechanical connection strength of the electrode connection structure can be further increased.

As described above, in the electrode connection structure according to the present embodiment, metal wire115fixed to second base material112is clamped together with first base material111and the like by two clamping portions114aand114bof fastening member114. Therefore, the mechanical connection strength of the electrode connection structure can be increased. As a result, the electrode connection structure can be made less prone to damage.

That is, by fixing metal wire115to second base material112, it is possible to increase the proof stress against local tensile stress in electrode lead-out portion10and the periphery of electrode lead-out portion10. Therefore, even when a load of tension is applied to cable116, it is possible to increase the mechanical connection strength in electrode lead-out portion10and the periphery of electrode lead-out portion10. In addition, since a general member such as a rivet can be used as fastening member114in the present embodiment, cable terminal117, electrode layer113, first base material111, and second base material112can be easily clamped.

In addition, in the electrode connection structure of PTL 1 described above, the antenna electrode needs to be protruded from the end of the base member in order to form the stacked portion. Therefore, it is necessary to separately prepare the antenna electrode and the base member and bond them.

However, since it is not necessary in the present embodiment to protrude electrode layer113from the ends of first base material111and second base material112when sensor110is viewed from the front or the rear surface, for example, a plurality of sensors110can be efficiently generated. Specifically, by forming a required number of electrode layers113for the plurality of sensors110on a base material for cutting out the plurality of first base materials111, and cutting out the plurality of first base materials111from the base material, the plurality of sensors110can be efficiently generated. In addition, by sewing a required number of metal wires115for the plurality of sensors110on a base material for cutting out the plurality of second base materials112, first base material111on which electrode layer113is formed may be joined to each of portions corresponding to their metal wires115. Then, by cutting out the plurality of second base materials from the base material, the plurality of sensors110can be efficiently generated.

Here, in the present embodiment, the surface of washer101, which is disposed on the side of clamping portion114bof fastening member114, of a pair of washers101may be covered with an insulating material. With this, even if washer101strongly abuts metal wire115and the insulating coating of metal wire115tears, it is possible to suppress the electrical continuity of metal wire115and electrode layer113via washer101and fastening member114.

The electrode connection structure according to the present embodiment further includes an insulating member in addition to the features included in the electrode connection structure according to Embodiment 1. Hereinafter, points of the electrode connection structure according to the present embodiment different from those of Embodiment 1 will be described, and detailed description of the same features as those of Embodiment 1 will be omitted.

FIG. 11is a rear view of grip sensor100according to the present embodiment.

As shown inFIG. 11, grip sensor100includes sensor110, control circuit120, and harness130, as in Embodiment 1. Here, in the present embodiment, sensor110includes two insulating members140.

Each of two insulating members140is disposed on the surface of second base material112so as to cover a part of metal wire115around two fastening members114. It should be noted that the front surface of second base material112is a surface of second base material112opposite to the first base material111side.

Such insulating member140is a member having electrical insulation and is, for example, a resin sheet, a rubber sheet, a non-woven fabric, or a metal sheet having an insulating surface.

FIG. 12is an exploded perspective view of sensor110in the present embodiment.

Each of the two insulating members140is disposed so as to cover the front surface (that is, the surface on the negative side in the Z-axis direction) of two second convex portions112bof second base material112. At this time, insulating member140is disposed so that the two through holes105formed in insulating member140communicate with through holes105of the two second convex portions112badjacent to each other. Then, insulating member140is clamped together with two electrode lead-out portions10by two fastening members114.

Specifically, when insulating member140is clamped, a pair of washers101corresponding to electrode lead-out portion10is disposed in each of two electrode lead-out portions10so as to clamp electrically conductive non-woven fabric102, electrode lead-out portion10, and insulating member140in the Z-axis direction. Furthermore, cable terminal117and fastening member114are disposed for each of two electrode lead-out portions10. At this time, the shaft of fastening member114used for one of two electrode lead-out portions10is inserted in through hole105penetrating electrode layer113, first convex portion111b, second convex portion112b, and insulating member140. Furthermore, the shaft of fastening member114used for the other of two electrode lead-out portions10is inserted in another through hole105that penetrates another electrode layer113, first convex portion111b, second convex portion112b, and insulating member140.

More specifically, the shaft of fastening member114is inserted in a hole of the ring of cable terminal117, a hole of the pair of washers101, and through hole105in each of electrically conductive non-woven fabric102, electrode lead-out portion10, and insulating member140from the positive side to the negative side in the Z-axis direction. Furthermore, the tip of the inserted fastening member114is crimped while protruding from washer101on the negative side in the Z-axis direction.

With this, in each of four electrode lead-out portions10, cable terminal117, which is one end of the electric wire, is fixed to fastening member114while being electrically connected to electrode layer113of electrode lead-out portion10via electrically conductive non-woven fabric102and washer101. The electrode connecting structure in the present embodiment includes such electrode lead-out portion10, fastening member114corresponding to electrode lead-out portion10, electrically conductive non-woven fabric102, cable terminal117, a pair of washers101, insulating member140, and metal wire115.

FIG. 13is a diagram showing a central portion of sensor110in the present embodiment. Specifically, (a) inFIG. 13shows a front center portion of sensor110, and (b) inFIG. 13shows a rear center portion of sensor110.FIG. 14is a cross-sectional view showing a cross section taken along the line B-B of sensor110shown in (a) inFIG. 13.

As shown inFIG. 14, shaft portion114cof fastening member114is inserted in through hole105in electrically conductive non-woven fabric102, electrode lead-out portion10, and insulating member140. Two clamping portions114aand114bare disposed on shaft portion114cso as to clamp the periphery of through hole105in each of electrically conductive non-woven fabric102, electrode lead-out portion10, and insulating member140in the axial direction of shaft portion114c. It should be noted that as in Embodiment 1, when fastening member114is a rivet, clamping portion114ais a head portion of the rivet, shaft portion114cis a body portion of the rivet, and clamping portion114bis a portion formed like a head portion by crimping the tip of the body portion.

In addition, also in the present embodiment as in Embodiment 1, clamping portions114aand114bof fastening member114clamp metal wire115fixed to second base material112in the Z-axis direction together with electrode lead-out portion10as shown inFIGS. 13 and 14. With this, also in the present embodiment, the mechanical connection strength of the electrode connection structure including electrode lead-out portion10can be increased.

Here, in Embodiment 1, when clamping portions114aand114bof fastening member114clamp metal wire115, metal wire115is strongly pressed against second base material112side by washer101disposed on the clamping portion114bside of the pair of washers101. As a result, by pressing washer101strongly against metal wire115, the insulating coating formed on the surface of metal wire115may peel off.

However, in the present embodiment, since insulating member140is disposed so as to cover metal wire115, it is possible to suppress washer101from abutting metal wire115directly. As a result, it is possible to suppress the coating of metal wire115from peeling off.

FIG. 15is a diagram showing an example of a part where metal wire115is clamped. Specifically,FIG. 15is an enlarged view of a part of metal wire115around clamping portion114bof fastening member114shown in (b) inFIG. 13.FIGS. 16 and 17are diagrams showing another example of a part where metal wire115is clamped.

As shown inFIGS. 15 to 17, also in the present embodiment, since metal wire115is clamped by fastening member114as in Embodiment 1, the mechanical connection strength of the electrode connection structure can be increased. Furthermore, since insulating member140is disposed so as to cover metal wire115in the present embodiment, it is possible to suppress the coating of metal wire115from peeling off. That is, the electrode connection structure in the present embodiment is disposed between metal wire115and one of two clamping portions114aand114b, and includes insulating member140clamped in the axial direction by two clamping portions114aand114b. With this, since insulating member140is disposed as a cushioning material between metal wire115and one of two clamping portions114aand114b, even if clamping portion114aor114bstrongly presses metal wire115to clamp the metal wire, it is possible to suppress metal wire115from being damaged. As a result, even if metal wire115is coated, it is possible to suppress the coating from peeling off.

In addition, the electrode connection structure in the present embodiment further includes insulating member140in addition to the configuration of Embodiment 1. This insulating member140is clamped together with two electrode lead-out portions10by two fastening members114. Therefore, the mechanical connection strength of the electrode connection structure can be further increased, and the electrode connection structure can be made less prone to damage. That is, insulating member140is clamped together with first base material111and the like by two clamping portions114aand114bof fastening member114fixed to one end of cable116. Furthermore, insulating member140is also clamped together with first base material111and the like by two clamping portions114aand114bof other fastening member114fixed to one end of other cable116. Therefore, for example, when a force is applied to shaft portion114cof fastening member114fixed to one end of one cable116by pulling one cable116, insulating member140receives the tensile stress. Here, insulating member140is also clamped together with first base material111, second base material112, and the like by other fastening member114. With this, first base material111and second base material112are reinforced. Therefore, insulating member140can suppress the movement of shaft portion114cof fastening member114fixed to one end of one cable116. Even if other cable116is pulled, insulating member140can similarly suppress the movement of shaft portion114cof other fastening member114fixed to one end of cable116. As a result, it is possible to suppress the periphery of first through hole105in electrode layer113, the first base material, and the second base material from being torn by shaft portion114c.

In addition, the electrode connection structure in the present embodiment includes first metal wire115and second metal wire115which are fixed to second base material112, respectively, as in Embodiment 1. In one fastening member114of two fastening members114that clamp insulating member140, two clamping portions114aand114bclamp first metal wire115fixed to second base material112in the axial direction of shaft portion114ctogether with electrode layer113, first base material111, second base material112, and insulating member140. In addition, also in the other fastening member114, two clamping portions114aand114bclamp second metal wire115fixed to second base material112in the axial direction of shaft portion114ctogether with other electrode layer113, first base material111, second base material112, and insulating member140. It should be noted that first metal wire115and second metal wire115may be the same metal wire or may be different metal wires electrically insulated with each other.

With this, also in the present embodiment, since first metal wire115fixed to second base material112is clamped together with first base material111and the like by one of fastening members114as in Embodiment 1, the mechanical connection strength of the electrode connection structure can be increased, and the electrode connection structure can be made less prone to damage. In addition, similarly to first metal wire115, second metal wire115fixed to second base material112is also clamped together with first base material111and the like by the other fastening member114. Therefore, also by second metal wire115, the mechanical connection strength of the electrode connection structure can be increased, and the electrode connection structure can be made less prone to damage.

In addition, in the present embodiment, insulating member140is clamped by two fastening members114, but may be clamped by only one fastening member114. In this case, insulating member140may be a metal washer having a surface with the electrical insulation.

It should be noted that since the electrode connection structure according to the present embodiment includes all the components of the electrode connection structure according to Embodiment 1, not only the working effects unique to the present embodiment but also the same working effects as in Embodiment 1 are obtained.

In the electrode connection structure according to the present embodiment, instead of clamping metal wire115by fastening member114as in Embodiment 1 described above, the mechanical connection strength of the electrode connection structure is increased by clamping insulating member140by a plurality of fastening members114as in Embodiment 2. Hereinafter, points of the electrode connection structure according to the present embodiment different from those of Embodiment 1 will be described, and detailed description of the same configurations as those of Embodiment 1 or 2 will be omitted.

FIG. 18is a front view of grip sensor100according to the present embodiment.FIG. 19is a rear view of grip sensor100according to the present embodiment.

As shown inFIGS. 18 and 19, grip sensor100includes sensor110, control circuit120, and harness130, as in Embodiments 1 and 2. Here, in sensor110according to the present embodiment, two fastening members114are arranged in each of the X-axis direction and the Y-axis direction as shown inFIG. 18. That is, four fastening members114are disposed in a matrix consisting of two columns in the X-axis direction and two rows in the Y-axis direction. In addition, one end side of each of four electrode layers113formed on first base material111protrudes toward the negative side in the X-axis direction so that four fastening members114are disposed in the above matrix.

Furthermore, in the present embodiment, insulating member140is disposed on the front surface of second base material112(the surface on the negative side in the Z-axis direction) as shown inFIG. 19. This insulating member140is clamped together with electrode layer113, first base material111, and second base material112by four fastening members114. Here, in the present embodiment, metal wire115is not clamped by fastening member114. Therefore, it is possible to suppress the coating of metal wire115from being peeled off by being clamped by fastening member114.

FIG. 20is an exploded perspective view of sensor110in the present embodiment.

In the present embodiment, first base material111does not include four first convex portions111bas in Embodiments 1 and 2, but includes only one first convex portion111b. That is, first base material111includes elongate first main base material111a, and one first convex portion111bwhich protrudes from first main base material111a. Specifically, one first convex portion111bprotrudes from the substantially center of the side of first main base material111aon the negative side in the X-axis direction to the negative side in the X-axis direction. One end side of each of four electrode layers113is formed in this one first convex portion111b. Through-holes105are formed in the four portions of first convex portion111b, that is, in the portions where one ends of four electrode layers113are formed, respectively.

Similar to first base material111, second base material112has only one second convex portion112b. That is, second base material112includes second main base material112afacing first main base material111a, and one second convex portion112bprotruding from second main base material112aand facing one first convex portion111b. Specifically, similar to first convex portion111b, one second convex portion112bprotrudes from the substantially center of the side of second main base material112aon the negative side in the X-axis direction to the negative side in the X-axis direction. In addition, four through holes105are formed in second convex portion112b.

Such first base material111and second base material112are stacked via a double-sided tape with through holes105formed in the respective base materials disposed to communicate with each other. At this time, the rear surface of first base material111and the rear surface of second base material112(that is, the surface on which metal wire115is not sewn) are joined by a double-sided tape. With this, first base material111and second base material112are bonded together. It should be noted that through hole105may be formed by drilling first base material111and second base material112after they are stacked via the double-sided tape. By such bonding, electrode lead-out portion10including first convex portion111bon which electrode layer113is formed and second convex portion112bthat is bonded together to face first convex portion111bis configured.

In addition, in the order of electrically conductive non-woven fabric102, washer101, and cable terminal117from the electrode layer113side, these members are disposed to be stacked in the periphery of through hole105in each of four electrode layers113. At this time, these members are disposed so that the respective holes communicate with each other.

Furthermore, in the present embodiment, insulating member140is disposed on the front surface of second convex portion112bof second base material112. Also at this time, insulating member140is disposed so that four through holes105of insulating member140communicate with four through holes105of second convex portion112b, respectively. Then, washer101is disposed in the periphery of each of four through holes105on the surface opposite to the second base material112side (that is, the front surface) of insulating member140. Also at this time, washer101is disposed so that the hole of washer101communicates with through hole105.

Then, the respective axes of four fastening members114are inserted in the holes of cable terminal117and the pair of washers101, and respective through holes105of electrode lead-out portion10and insulating member140, for example, from the positive side to the negative side in the Z-axis direction. Furthermore, the tip of the inserted fastening member114is crimped while protruding from washer101on the negative side in the Z-axis direction.

FIG. 21is a diagram showing a central portion of sensor110according to the present embodiment. Specifically, (a) inFIG. 21shows a front center portion of sensor110, and (b) inFIG. 21shows a rear center portion of sensor110.FIG. 22is a cross-sectional view showing a cross section taken along line C-C of sensor110shown in (a) inFIG. 21.

As shown inFIG. 22, shaft portion114cof fastening member114is inserted in the respective holes of cable terminal117and washer101, and further inserted in through holes105of electrically conductive non-woven fabric102, electrode lead-out portion10, and insulating member140. Furthermore, shaft portion114cis inserted in the hole of washer101disposed in insulating member140.

Two clamping portions114aand114bare disposed on shaft portion114c. These two clamping portions114aand114bare clamp the periphery of through hole105in each of electrically conductive non-woven fabric102, electrode lead-out portion10, and insulating member140via cable terminal117and a pair of washers101in the axial direction of shaft portion114c. It should be noted that as in Embodiment 1, when fastening member114is a rivet, clamping portion114ais a head portion of the rivet, shaft portion114cis a body portion of the rivet, and clamping portion114bis a portion formed like a head portion by crimping the tip of the body portion.

Here, in the present embodiment, unlike the first and second embodiments, clamping portions114aand114bof fastening member114clamp no metal wire115fixed to second base material112as shown in (b) inFIG. 21andFIG. 22. That is, metal wire115is not strongly pressed to the second base material112side by clamping portion114band washer101. This can suppress the coating of metal wire115from peeling off.

In addition, in the present embodiment, insulating member140is clamped together with electrode lead-out portion10by four fastening members114. In other words, insulating member140is fastened together with electrode lead-out portion10by the four fastening members.

With this, in the present embodiment, the mechanical connection strength of the electrode connection structure including electrode lead-out portion10can be increased. For example, when a force is applied to shaft portion114cof fastening member114fixed to cable terminal117by pulling cable116connected to cable terminal117, insulating member140receives the tensile stress. Since this insulating member140is fastened together with electrode lead-out portion10by four fastening members114as described above, it reinforces second base material112and insulating member140can suppress the movement of shaft portion114cof fastening member114fixed to cable terminal117. As a result, the periphery of through hole105in electrode layer113, first base material111, and second base material112can be suppressed from being torn by shaft portion114c.

In the present embodiment, the electrode connection structure includes four electrode layers113and four fastening members114, but the number thereof is not limited to four, and it may be any number of two or more. That is, the electrode connection structure according to the present embodiment includes at least two electrode layers113; at least two fastening members114corresponding to electrode layers113; and insulating member140clamped by fastening members114. At least two electrode layers113include, for example, first electrode layer113and second electrode layer113among four electrode layers113described above. In addition, at least two fastening members114include, for example, first fastening member114and second fastening member114among four fastening members114described above. By these fastening members114, one ends of cables116that are the first electric wire and the second electric wire are fastened to first base material111and second base material112, respectively.

Therefore, the electrode connection structure in the present embodiment includes first base material111; first electrode layer113and second electrode layer113formed on one surface of first base material111; second base material112disposed on the surface opposite to the one surface of first base material111; first fastening member114for fastening one end of cable116that is a first electric wire to first base material111and second base material112; second fastening member114for fastening one end of cable116that is a second electric wire to first base material111and second base material112; and insulating member140.

First fastening member114includes first shaft portion114cinserted in first through hole105penetrating first electrode layer113, first base material111, second base material112, and insulating member140; and two first clamping portions114aand114bdisposed in first shaft portion114cso as to clamp the periphery of first through hole105in each of first electrode layer113, first base material111, second base material112, and insulating member140in the axial direction of first shaft portion114c.

Similarly, second fastening member114includes second shaft portion114cinserted in second through hole105penetrating second electrode layer113, first base material111, second base material112, and insulating member140; and two second clamping portions114aand114bdisposed in second shaft portion114cso as to clamp the periphery of second through hole105in each of second electrode layer113, first base material111, second base material112and insulating member140in the axial direction of second shaft portion114c. One end of cable116that is the first electric wire is fixed to first fastening member114while being electrically connected to first electrode layer113, and one end of cable116that is the second electric wire is fixed to second fastening member114while being electrically connected to second electrode layer113.

With this, insulating member140is clamped together with first base material111, second base material112, and the like by two first clamping portions114aand114bof first fastening member114and two second clamping portions114aand114bof second fastening member114. Therefore, the mechanical connection strength of the electrode connection structure can be increased, and the electrode connection structure can be made less prone to damage. That is, insulating member140is clamped together with first base material111and the like by two first clamping portions114aand114bof first fastening member114fixed to one end (specifically, cable terminal117) of first electric wire such as cable116. Furthermore, insulating member140is also clamped together with first base material111and the like by two second clamping portions114aand114bof second fastening member114fixed to one end (specifically, cable terminal117) of second electric wire such as other cable116. Therefore, for example, when a force is applied to first shaft portion114cof first fastening member114fixed to one end of cable116by pulling cable116that is the first electric wire, insulating member140receives the tensile stress. Here, insulating member140is also clamped together with first base material111, second base material112, and the like by second fastening member114. With this, first base material111and second base material112are reinforced. Therefore, insulating member140can suppress the movement of first shaft portion114cof first fastening member114fixed to one end of cable116that is the first electric wire. Even if the second electric wire that is other cable116is pulled, insulating member140can similarly suppress the movement of second shaft portion114cof second fastening member114fixed to one end of the second electric wire. As a result, it is possible to suppress the periphery of first through hole105in first electrode layer113, the first base material, and the second base material from being torn by first shaft portion114c. Similarly, it is possible to suppress the periphery of second through hole105in second electrode layer113, the first base material, and the second base material from being torn by second shaft portion114c.

Here, in the present embodiment, insulating member140is disposed between second base material112and four clamping portions114b. That is, insulating member140is disposed between second base material112and one of two first clamping portions114aand114b, and between second base material112and one of two second clamping portions114aand114b.

With this, since insulating member140is disposed as a cushioning material between second base material112and clamping portion114b, even if second base material112is strongly pressed due to clamping portion114bclamping second base material112, the local pressure on second base material112can be relieved.

In Embodiment 3, insulating member140is disposed on the front surface (the surface on the negative side in the Z-axis direction) of second base material112, but may be disposed on the back surface (the surface on the positive side in the Z-axis direction) of second base material112.

In the electrode connection structure of Embodiment 3, the mechanical connection strength can be increased as described above. That is, insulating member140is clamped together with first base material111and the like by respective two clamping portions114aand114bof four fastening members114. Therefore, even if cable116fixed to fastening member114is pulled, the periphery of first through hole105in electrode layer113, first base material111, and second base material112can be suppressed from being torn by shaft portion114cof fastening member114. However, metal wire115is not clamped together with insulating member140, first base material111, and the like by fastening member114. Therefore, when metal wire115is pulled, the portion of second base material112to which metal wire115is sewn may be torn by metal wire115. Alternatively, the portion may be deformed or damaged.

Thus, the electrode connection structure according to the present embodiment includes a banding member for suppressing metal wire115from being pulled. This can suppress second base material112from being torn.

FIG. 23is a diagram showing a part of the electrode connection structure according to Embodiment 4.

The electrode connection structure according to the present embodiment is different from the electrode connection structure according to Embodiment 3 in that it further includes four fastening members151each corresponding to a third fastening member, and banding member150.

Each of four fastening members151is a member for fastening one end of cable152corresponding to the third electric wire to first base material111and second base material112.

Banding member150is a member that bands at least one of four cables116corresponding to either the first electric wire or the second electric wire and cable152.

Specifically, in the present embodiment, protruding portions protruding toward the negative side in the X axis direction are formed at both ends in the Y-axis direction of electrode lead-out portions10of first base material111and second base material112. That is, protruding portions112cprotruding toward the negative side in the X-axis direction are formed at both ends in the Y-axis direction of second convex portion112bof second base material112. Both ends of each of two metal wires115are fixed by being sewn to protruding portion112c. Then, each of both ends of metal wire115is electrically and structurally connected to cable152by fastening member151. That is, fastening member151fastens cable152to first base material111and second base material112by electrically and structurally connecting one end of cable152to one end of metal wire115.

In addition, in the present embodiment, each of two cables152includes core cable152band two end cables152aformed by branching the tip side of core cable152b. Each of two end cables152ais connected to the end of metal wire115sewn to protruding portion112cvia fastening member151. For example, fastening member151includes a crimp terminal for connecting the end of metal wire115and the end of terminal cable152a, and solder for electrically sufficiently connecting and fixing the ends. In addition, the base end side of core cable152bopposite to the tip end side is connected to control circuit120. That is, though both ends of metal wire115are not sewn to second base material112and are directly connected to control circuit120in Embodiments 1 to 3, both ends of metal wire115are sewn to second base material112in the same manner as the other portions except the both ends in the present embodiment. Then, each of both ends of metal wire115is connected to control circuit120via cable152.

Banding member150bands cable116connected to each of two fastening members114on the negative side in the Y-axis direction and core cable152bof each of two cables152. Such banding member150may be, for example, a banding band, a vinyl tape, or a heat shrink tube. When a banding band is used for banding member150, two cables116and two core cables152bcan be banded easily by using the banding band in the final step of manufacturing the electrode connection structure or grip sensor100. In addition, since the banding strength is high, it is possible to effectively suppress the deviation of two cables116and two core cables152bthat are banded together. In addition, even if any of two cables116and two core cables152bis pulled, banding member150can be suppressed from sliding and deforming. In addition, the width of the banding band is generally shorter than the width of the vinyl tape. Therefore, even if the width of the portion of two cables116and two core cables152bwhere they can be banded is short, their cables can be easily banded using a banding band for banding member150.

It should be noted that the distance in cable116from the part banded by banding member150to fastening member114is shorter than the distance in cable152from the part banded by banding member150to fastening member151.

In addition, the electrode connection structure according to the present embodiment may include covering member153athat covers two fastening members151disposed on protruding portion112cof second base material112and covering member153bthat covers each of the branched portions of the two cables152. By these covering members153aand153b, fastening members151and the branched portions can be protected. It should be noted that inFIG. 23, only the simplified outer periphery of covering members153aand153bare shown by a dashed-dotted line in order to make fastening member151and the branched portion easy to understand.

In such electrode connection structure according to the present embodiment, since four fastening members114fasten insulating member140together with electrode lead-out portion10as in Embodiment 3, the mechanical strength of the peripheral portion of each of four fastening members114in electrode lead-out portion10is high. Therefore, even if each of four cables116is pulled, the peripheral portion of each of four fastening members114in electrode lead-out portion10can be suppressed from being torn by the fastening member114.

On the other hand, the mechanical strength of the peripheral portion of each of two fastening members151in protruding portion112cof second base material112is weaker than the mechanical strength of the peripheral portion of fastening member114in second base material112. That is, when end cable152ais pulled, the pulling force is transmitted to the end of metal wire115via fastening member151. As a result, metal wire115sewn to protruding portion112cis pulled due to the pulling force, and protruding portion112cmay be torn by metal wire115.

Therefore, the electrode connection structure according to the present embodiment includes banding member150so that even if cable152connecting to fastening member151is pulled, the pulling force is not transmitted to the peripheral portions of each of two fastening members151in protruding portion112c.

Specifically, when core cable152bof each of two cables152is pulled, the pulling force is transmitted to fastening member114via banding member150and cable116. That is, when the part of core cable152bon the control circuit120side is pulled, the pulling force is transmitted to fastening member114, not to fastening member151on the metal wire115side.

Therefore, even if the pulling force is transmitted to fastening member114by pulling core cable152b, the peripheral portion of fastening member114in electrode lead-out portion10has a high mechanical strength, so that the peripheral portion can be suppressed from being torn. That is, even if core cable152bof each of two cables152is pulled, the pulling force can be suppressed from being transmitted to fastening member151on the metal wire115side to protect protruding portion112cof second base material112.

The electrode connection structure according to the present embodiment has a configuration in which banding member150is included in the electrode connection structure according to Embodiment 3, but it may has a configuration in which banding member150is included in the electrode connection structure according to Embodiment 1 or 2. In this case, the electrode connection structure includes, for example, the configuration of the electrode connection structure of Embodiment 1, another fastening member, and a banding member. The other fastening member is a member for fastening one end of another electric wire different from cable116(that is, the electric wire) to first base material111and second base material112. The banding member is a member that bands cable116and another electric wire. Specifically, the other fastening member fastens the other electric wire to first base material111and second base material112by electrically and structurally connecting one end of the other electric wire to one end of metal wire115. It should be noted that the other electric wire and the other fastening member correspond to cable152and fastening member151in the present embodiments.

Even with such a configuration, the same effect as that of the present embodiment can be obtained.

Other Modifications

The electrode connection structure according to the present disclosure has been described above based on each of the embodiments described above, but the present disclosure is not limited to these embodiments. Various modifications that one of skilled in the art may conceive may be included in the scope of the present disclosure without departing from the spirit of the present disclosure.

For example, although metal wire115in each of the embodiments described above is used as a heater element, it may be used for other purposes. For example, metal wire115may be used as a disturbance noise detection electrode. That is, metal wire115having an electrically insulated surface is a disturbance noise detection electrode for detecting disturbance noise with respect to the signal detected in electrode layer113. In this case, control circuit120acquires the disturbance noise signal from metal wire115that is the disturbance noise detection electrode. Then, control circuit120corrects the output signal of electrode layer113, for example, by subtracting the value indicated by the disturbance noise signal from the value indicated by the output signal of electrode layer113. With this, the measurement value based on the electrostatic capacitance generated in electrode layer113can be appropriately acquired while suppressing the influence of disturbance noise. As a result, control circuit120can detect the grip of rim210by the hand more accurately. It should be noted that not only one of the heater element and the disturbance noise detection electrode but also both of them may be disposed on second base material112. In this case, two clamping portions114aand114bmay clamp only one of the metal wire of the heater element and the metal wire of the disturbance noise detection electrode, or may clamp both of them. In addition, metal wire115may be used as a functional element other than the heater element and the disturbance noise detection electrode.

In addition, although metal wire115in each of the embodiments described above is used as a heater element, it may be provided exclusively for reinforcing second base material112, separately from the heater element or separately from the disturbance noise detection electrode. Furthermore, when neither the heater element nor the disturbance noise detection electrode is required, metal wire115may be provided only on electrode lead-out portion10where second base material112needs to be reinforced and the periphery of electrode lead-out portion10. In these cases, the length of metal wire115may be set to the minimum required.

In addition, although metal wire115in each of the embodiments described above is fixed to second base material112by being sewn to second base material112, it may be fixed to second base material112by another method.

In addition, when metal wire115in each of the embodiments described above is used as a heater element or a disturbance noise detection electrode, such a configuration that metal wire115is directly connected to control circuit120is shown in each of the embodiments described above, for example, as shown inFIG. 19, but a configuration is not limited thereto. That is, the heater element or the disturbance noise detection electrode may be connected to an external circuit such as control circuit120by the electrode connection structure described in each of the embodiments described above.

In addition, the electrode connection structure in each of the embodiments described above is provided in grip sensor100, but it is not limited to grip sensor100and it may be provided in any device as long as it is a device used by connecting one end of an electric wire to an electrode.

The disclosures of the following Japanese Patent Applications including specification, drawings and claims are incorporated herein by reference in their entirety: Japanese Patent Application No. 2018-082375 filed on Apr. 23, 2018 and Japanese Patent Application No. 2018-204579 filed on Oct. 31, 2018.

INDUSTRIAL APPLICABILITY

The electrode connection structure of the present disclosure has an effect of being less likely to be damaged, and is applicable to, for example, a grip sensor or the like disposed on a steering wheel or a door handle of a vehicle, a grip of a motorcycle, or the like.