Electrode structure, steering wheel, and method of manufacturing the steering wheel

Abstract

To provide an electrode structure, a steering wheel, and a method for manufacturing the steering wheel capable of suppressing soaring of manufacturing cost of the steering wheel while securing external appearance of the steering wheel.SOLUTION: An electrode structure 20 comprises: an insulator; and a linear first electrode 31 arranged on a first surface 21a being a surface opposite to a surface of a core metal 11 side on the insulator. The insulator has an engagement portion that engages with a to-be-engaged portion provided on the core metal 11. Then, after engaging the electrode structure 20 with the core metal 11, a foam 15 is molded to form the steering wheel 1.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to an electrode structure, a steering wheel, and a method for manufacturing a steering wheel. [Background technology]

[0002] Conventionally, a method has been disclosed in which a cutting tool is used to make a cut in the foam of a steering wheel, and a conductor for a sensor is introduced into each of a first layer and a second layer of the cut (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2018 / 145868 Summary of the Invention [Problem to be solved by the invention]

[0004] However, because cuts are made in the foam of the steering wheel, there is room for improvement in appearance. Also, the number of steps required for the cuts and for introducing the sensor conductors increases. Furthermore, if the steering wheel is equipped with a heater function, a heater wire must also be installed in the steering wheel. For these reasons, there is room for improvement in the manufacturing cost of the steering wheel.

[0005] Therefore, the present disclosure provides an electrode structure, a steering wheel, and a method for manufacturing a steering wheel that can prevent the manufacturing costs of the steering wheel from rising while ensuring the appearance of the steering wheel. [Means for solving the problem]

[0006] An electrode structure according to one embodiment of the present disclosure is an electrode structure arranged along the outer periphery of a core of a steering wheel provided in a vehicle, and comprises an insulator and a linear first electrode arranged on a first surface of the insulator opposite to the surface facing the core, and the insulator has an engaging portion that engages with the core.

[0007] These comprehensive or specific aspects may be realized by a system, an apparatus, a method, a recording medium, or a computer program, or may be realized by any combination of a system, an apparatus, a method, a recording medium, and a computer program. [Effects of the Invention]

[0008] The electrode structure etc. of the present disclosure can prevent the manufacturing costs of the steering wheel from rising while ensuring the appearance of the steering wheel. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing a vehicle interior in which a steering wheel according to an embodiment is arranged. [Figure 2] FIG. 2 is a perspective view showing the steering wheel of the embodiment, a cross-sectional view of the core metal taken along the dashed line in FIG. 2, and a partially enlarged view showing the electrode structure. [Figure 3] 3 is a cross-sectional view showing the first engaged portion and the first engaging portion of the steering wheel taken along line AA in FIG. [Figure 4] FIG. 4 is a perspective view showing a first engaged portion, a second engaged portion, and a second engaging portion of the steering wheel in the embodiment. [Figure 5] 5 is a cross-sectional view showing the second engaged portion and the second engaging portion of the steering wheel taken along line BB in FIG. [Figure 6] FIG. 6 is a block diagram showing a steering wheel according to the embodiment. [Figure 7A] FIG. 7A is a plan view showing the first electrode. [Figure 7B] FIG. 7B is a plan view showing another first electrode. [Figure 8] FIG. 8 is a flowchart showing a method for manufacturing a steering wheel according to an embodiment. [Figure 9] FIG. 9 is a perspective view showing a steering wheel according to a first modification of the embodiment and a cross-sectional view of a core metal. [Figure 10] 10 is a cross-sectional view showing the first engaged portion and the first engaging portion of the steering wheel taken along line CC in FIG. [Figure 11] FIG. 11 is a cross-sectional view showing the second engaged portion and the second engaging portion of the steering wheel. [Figure 12] FIG. 12 is a cross-sectional view showing the first engaged portion and the first engaging portion of the steering wheel. [Figure 13] FIG. 13 is a cross-sectional view showing the second engaged portion and the second engaging portion of the steering wheel. [Figure 14] FIG. 14 is a cross-sectional view showing the first engaged portion and the first engaging portion of the steering wheel. DETAILED DESCRIPTION OF THE INVENTION

[0010] An electrode structure according to one embodiment of the present disclosure is an electrode structure arranged along the outer periphery of a core of a steering wheel provided in a vehicle, and comprises an insulator and a linear first electrode arranged on a first surface of the insulator opposite to the surface facing the core, and the insulator has an engaging portion that engages with the core.

[0011] This allows the electrode structure to be attached to the core bar in advance, which means that the electrode structure can be placed inside the steering wheel when the steering wheel is being formed. This eliminates the need to form the steering wheel and then cut a notch in the steering wheel to place the first electrode, as in the prior art.

[0012] Therefore, the electrode structure can prevent the manufacturing costs from rising while ensuring the appearance of the steering wheel.

[0013] In the electrode structure according to the aspect of the present disclosure, the first electrode serves both as a sensor electrode that detects gripping of the steering wheel and as a heater wire that heats the steering wheel.

[0014] This allows the first electrode to serve as both a sensor electrode and a heater wire, eliminating the need to provide a separate heater wire in the steering wheel, thereby preventing the manufacturing costs of steering wheels using the electrode structure from rising.

[0015] In the electrode structure according to the aspect of the present disclosure, the first electrode is a heater wire that heats the steering wheel.

[0016] According to this, the steering wheel can be heated by the linear first electrode provided in the electrode structure attached to the core metal.

[0017] In the electrode structure according to the aspect of the present disclosure, the first electrode is a sensor electrode that detects gripping of the steering wheel.

[0018] With this, gripping of the steering wheel can be detected by the linear first electrode provided in the electrode structure attached to the core metal.

[0019] The electrode structure according to one embodiment of the present disclosure also includes a second electrode disposed on a second surface of the insulator opposite to the first surface.

[0020] This allows the electrode structure including the second electrode to be attached to the core bar in advance. This allows the electrode structure to be disposed inside the steering wheel when the steering wheel is being formed. This eliminates the need to form the steering wheel and then cut a cut in the steering wheel to dispose the second electrode, as in the prior art.

[0021] In addition, an electrode structure according to one embodiment of the present disclosure is an electrode structure arranged along the outer periphery of a core of a steering wheel provided in a vehicle, and comprises a first insulator, a resin sheet arranged on a first surface which is the surface of the first insulator opposite to the surface facing the core, a linear first electrode arranged on one surface of the resin sheet, and a second electrode arranged on the other surface which is the surface facing the first surface and is the back surface of the one surface of the resin sheet, wherein the first insulator has an engagement portion which engages with the core, and the first electrode serves as both a sensor electrode which detects gripping of the steering wheel and a heater wire which heats the steering wheel.

[0022] This allows the first electrode to be disposed on one side of a single resin sheet, and the second electrode to be disposed on the other side. Therefore, compared to using resin sheets for both the first electrode and the second electrode, the electrode structure of the present disclosure can suppress an increase in the number of parts, thereby suppressing a rise in manufacturing costs. Furthermore, this electrode structure also achieves the same effects as those described above.

[0023] A steering wheel according to one aspect of the present disclosure includes an electrode structure, the core metal, and a foam covering the core metal.

[0024] This steering wheel also provides the same effects as those described above.

[0025] In addition, a method for manufacturing a steering wheel according to one aspect of the present disclosure includes engaging the engaging portion of the electrode structure of the steering wheel with an engaged portion provided on the core wire, and covering the core wire with the foam while the engaging portion is engaged with the engaged portion.

[0026] According to this, by engaging the engaging portion with the engaged portion of the core, the electrode structure and the core can be firmly fastened together. This makes it possible to prevent the insulator from shifting in position relative to the core or from rotating around the circumference of the steering wheel due to pressure during resin molding of the steering wheel. This steering wheel manufacturing method also achieves the same effects as those described above.

[0027] In addition, in the electrode structure, in a cross section of the steering wheel cut along a plane perpendicular to the circumferential direction of the steering wheel, the first electrode is formed along the shape of the first surface of the insulator, and the second electrode is formed along the shape of the second surface of the insulator.

[0028] This allows the distance between the first electrode and the second electrode to be made uniform, so that accurate detection is possible regardless of which part of the steering wheel the driver is holding with his or her hands in the area where the electrode structure is installed.

[0029] In addition, in the electrode structure, the insulator includes a first insulator and a second insulator, the first insulator has the first surface and the second surface formed thereon, the first electrode is disposed on the first surface of the first insulator, the second electrode is disposed on the second surface of the first insulator, which is the surface opposite to the first surface, and the second insulator is disposed between the second electrode and the core and has the engaging portion that engages with the core.

[0030] This allows the second insulator to dispose the second electrode in a state spaced apart from the core, and the first insulator to dispose the first electrode in a state spaced apart from the second electrode and the core. Furthermore, because the first electrode and the second electrode can be disposed on the first insulator, a member in which the first insulator, the first electrode, and the second electrode are integrated can be easily assembled to the core.

[0031] In addition, in the electrode structure, the first insulator, the second insulator, the first electrode, and the second electrode are arranged in a range from at least the outer circumferential side of the steering wheel to the inner circumferential side of the steering wheel in a cross section obtained by cutting the steering wheel along a plane perpendicular to the circumferential direction of the steering wheel.

[0032] This allows the electrode structure to be located at a position where the driver's hands are likely to come into contact with the surface of the steering wheel when the driver grips the steering wheel, making it possible to detect whether the driver's hands are gripping the steering wheel.

[0033] In addition, in the electrode structure, the first insulator is made of a resin material, the second insulator is made of a resin material, the first electrode is configured to include metal plating or a metal thin film, and the second electrode is configured to include metal plating, a metal thin film, a metal sheet, or a metal plate.

[0034] This allows the first electrode and the second electrode to be disposed on the first insulator, and therefore the member in which the first insulator, the second insulator, the first electrode, and the second electrode are integrated can be easily assembled to the core. Furthermore, since the second insulator is disposed between the first insulator and the second electrode and the core, the second insulator can be disposed so that the first electrode is spaced apart from the core.

[0035] In addition, in the electrode structure, the first insulator is made of a resin material, the second insulator is made of a resin material, the first electrode has a resin sheet and a conductive wire, the conductive wire is arranged on the surface of the resin sheet opposite to the first surface side and sewn with sewing thread, and the second electrode is configured to include metal plating, a metal thin film, a metal sheet, or a metal plate.

[0036] According to this, when the first electrode is disposed on the first surface of the first insulator and the second electrode is disposed on the second surface of the first insulator, the resin sheet is soft enough to allow a conductor to be sewn to it with sewing thread, so the first electrode and the second electrode can be easily disposed to follow the shape of the first insulator without performing a forming process to follow the shapes of the first and second surfaces. This makes it possible to suppress an increase in the number of steps required to dispose the first electrode on the first surface of the first insulator and the second electrode on the second surface of the first insulator.

[0037] In the electrode structure, the first insulator has a first positioning portion, and the second insulator has a second positioning portion that engages with the first positioning portion.

[0038] This allows the first positioning portion and the second positioning portion to mesh together when assembling the first insulator to the second insulator, thereby aligning the first insulator with the second insulator, preventing misalignment between the first insulator and the second insulator in the circumferential direction and making the assembly easy and appropriate.

[0039] In the electrode structure, the first electrode is used exclusively as the sensor electrode and the first electrode is used exclusively as the heater wire.

[0040] According to this, for example, when driving a vehicle in a cold region, not only can the steering wheel be warmed by turning on the heater function and supplying power to the first electrode (heater wire), but it can also detect whether the driver is gripping the steering wheel.

[0041] Furthermore, in the electrode structure, when the first electrode is used as the sensor electrode, an AC voltage having the same phase as the AC voltage applied to the second electrode is applied to the first electrode.

[0042] This allows the capacitance formed between the first electrode and the core metal to be canceled or reduced when the first electrode is used as a sensor electrode, and therefore, by using a control circuit that detects when the driver's hands are gripping the steering wheel, the control circuit can accurately detect the capacitance formed between the first electrode and the driver's hands when the hands grip the steering wheel.

[0043] In the electrode structure, the engaging portion is engaged with an engaged portion provided on the core metal.

[0044] According to this, the engagement between the engaged portion and the engaging portion can ensure the distance between the first electrode and the insulator and maintain the posture at the same time, which makes it possible to incorporate the electrode structure into the steering wheel when the steering wheel is molded from resin.

[0045] Furthermore, simply by engaging the engaged portion with the engaging portion, the first insulator can position the first electrode and the second electrode in a state spaced apart from the core bar, and the component in which the first insulator and the first electrode are integrated can be easily assembled to the core bar.

[0046] Furthermore, the engagement between the engaged portion and the engaging portion allows the electrode structure to be firmly fastened to the core metal. This prevents the insulator from being displaced relative to the core metal or from being rotated around the circumference of the steering wheel due to pressure during resin molding of the steering wheel. As a result, an increase in the number of steps required for manufacturing the steering wheel can be prevented, and an increase in manufacturing costs can be prevented.

[0047] Hereinafter, the embodiments will be specifically described with reference to the drawings.

[0048] The embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, component placement and connection configurations, steps, and step order shown in the following embodiments are merely examples and are not intended to limit the present disclosure. Furthermore, among the components in the following embodiments, components not described in the independent claims are described as optional components.

[0049] In addition, each drawing is a schematic diagram and is not necessarily an exact illustration. In addition, the same components are denoted by the same reference numerals in each drawing.

[0050] Furthermore, in the following embodiments, expressions such as "approximately equal intervals" or "T-shaped" are used. For example, "approximately equal intervals" or "T-shaped" does not only mean completely equal intervals or T-shaped, but also means substantially equal intervals or T-shaped, that is, with an error of about a few percent. Furthermore, "approximately equal intervals" or "T-shaped" means equal intervals or T-shaped within the scope in which the effects of the present disclosure can be achieved. The same applies to other expressions using "approximately" or "shaped."

[0051] (Embodiment) <Configuration> First, the configuration of the steering wheel 1 will be described with reference to FIGS. 1 to 7B.

[0052] FIG. 1 is a diagram showing the cabin of a vehicle 3 in which a steering wheel 1 according to an embodiment is disposed. FIG. 2 is a perspective view of the steering wheel 1 according to an embodiment, a cross-sectional view of the core metal 11 taken along the dashed line in FIG. 2, and a partially enlarged view of the electrode structure 20. In the partially enlarged view of FIG. 2 showing the first positioning portion 21t of the first insulator 21 and the second positioning portion 22t of the second insulator 22, the harnesses 8a, 8b, and 8c are omitted. FIG. 3 is a cross-sectional view showing the first engaged portion 11c1 and the first engaging portion 23a of the steering wheel 1 taken along line AA in FIG. 2. FIG. 4 is a perspective view showing the first engaged portion 11c1, the second engaged portion 11c2, and the second engaging portion 23b of the steering wheel 1 according to an embodiment. FIG. 5 is a cross-sectional view showing the second engaged portion 11c2 and the second engaging portion 23b of the steering wheel 1 taken along line BB in FIG. 4. FIG. 6 is a block diagram showing the steering wheel 1 according to an embodiment. FIG. 7A is a plan view showing the first electrode 31. FIG. 7B is a plan view showing another first electrode 31. As shown in FIG.

[0053] As shown in FIGS. 1 and 2, a steering wheel 1 can apply a steering angle to the steered wheels of a vehicle 3, for example.

[0054] The steering wheel 1 has a rim 10. The rim 10 is integrally formed with T-shaped spokes 9 arranged on the inner circumferential surface of the rim 10.

[0055] The rim 10 includes a core metal 11, an electrode structure 20, and a foam body 15 that covers the electrode structure 20.

[0056] [Core 11] As shown in FIGS. 2 and 3, the core 11 is a metal, annular core. Specifically, the core 11 has a first annular portion 11a, a second annular portion 11b disposed on the inner circumferential side of the first portion 11a, and a curved portion 11c connecting the first portion 11a and the second portion 11b. One end edge of the first portion 11a is connected to one end edge of the curved portion 11c, and one end edge of the second portion 11b is connected to the other end edge of the curved portion 11c. In other words, the curved portion 11c is located between the first portion 11a and the second portion 11b in a cross section of the core 11 taken along a plane perpendicular to the circumferential direction of the core 11 (hereinafter, sometimes referred to as the cross section of the core 11). The cross section of such a core 11 may be U-shaped, V-shaped, J-shaped, C-shaped, or the like. FIG. 2 illustrates a case where the cross section of the core 11 is U-shaped. In this embodiment, in the cross section of the core metal 11, the first portion 11a and the second portion 11b are linear.

[0057] Furthermore, since the cross section of the core metal 11 is U-shaped, V-shaped, J-shaped, C-shaped, or the like, the first portion 11a, the second portion 11b, and the curved portion 11c form a recess 10a in the core metal 11. The recess 10a is a circular groove. In this embodiment, the opening of the recess 10a is formed on the front side of the rim 10 of the vehicle 3 (the side opposite the seat side of the rim 10).

[0058] As shown in FIGS. 3 and 4, the recess 10a is formed with a first engaged portion 11c1 and a second engaged portion 11c2.

[0059] The first engaged portion 11c1 is formed on the back surface of the curved portion 11c, which is on the recess 10a side, and is a cylindrical or tubular protrusion that stands upright from the back surface. An insertion hole 11d is formed inside the first engaged portion 11c1, into which a fastening member 19 such as a screw and the first engaging portion 23a of the second insulator 22 can be inserted. A screw hole 11d1 is formed at the bottom of the first engaged portion 11c1, in other words, at the tip of the first engaged portion 11c1, into which the fastening member 19 can be inserted. The first engaged portion 11c1 is included in the engaged portion.

[0060] As shown in FIGS. 4 and 5, the second engaged portion 11c2 is composed of an insertion hole 11c3 and a standing wall 11c4 formed in the recess 10a. The second engaging portion 23b of the second insulator 22 is inserted into the insertion hole 11c3. The standing wall 11c4 is a plate-like protrusion formed on the back surface of the curved portion 11c, which faces the recess 10a, and stands upright from the back surface. The standing wall 11c4 is engageable with the second engaging portion 23b inserted into the insertion hole 11c3. The second engaged portion 11c2 is included in the engaged portion.

[0061] [Electrode structure 20] 1 and 2, the electrode structure 20 is used in a device that detects the grip of the steering wheel 1 by the driver's hands. Specifically, the electrode structure 20 is arranged along the outer periphery of the core metal 11 of the steering wheel 1 provided in the vehicle 3 so as to easily detect the grip of the steering wheel 1. More specifically, the electrode structure 20 is provided on the core metal 11 so as to cover the first portion 11a of the core metal 11 through the curved portion 11c to the second portion 11b, that is, to cover the core metal 11 from the outer periphery to the inner periphery. In other words, the multiple electrode structures 20 are provided on the core metal 11 so as to cover the core metal 11 except for the recessed portion 10a of the core metal 11.

[0062] The electrode structure 20 is electrically connected to a control circuit 40 (see FIG. 1) that can detect when the driver's hands are gripping the steering wheel 1. When the driver's hands grip the rim 10, the capacitance between the electrodes of the electrode structure 20 and the driver's hands changes. The control circuit 40 detects the grip based on an output signal indicating the change in capacitance from the electrodes of the electrode structure 20. Specifically, the control circuit 40 measures the capacitance of the electrodes or a value (amount of change) corresponding to that capacitance, and detects that the driver's hands are gripping the rim 10 based on that value. Such a control circuit 40 is configured as a dedicated circuit or a general-purpose processor.

[0063] The electrode structure 20 is disposed on a steering wheel 1 provided on a vehicle 3. In this embodiment, the electrode structure 20 is embedded in the rim 10 of the steering wheel 1. FIG. 1 and other figures illustrate a case in which the electrode structures 20 are provided on the left and right sides of the rim 10. While FIG. 1 and other figures illustrate a case in which a pair of electrode structures 20 are provided on the rim 10, the present invention is not limited to this. For example, three or more electrode structures 20 may be provided on the rim 10, or only one electrode structure 20 may be provided on the rim 10. The electrode structure 20 may also be provided around the entire circumference of the annular rim 10.

[0064] As shown in FIGS. 2 and 3, the electrode structure 20 includes a first insulator 21, a second insulator 22, a first electrode 31, and a second electrode 32.

[0065] The first insulator 21 is arranged along the inner peripheral surface of the core 11 in a cross section of the rim 10 taken along a plane perpendicular to the circumferential direction of the rim 10 of the steering wheel 1 (hereinafter sometimes referred to as the cross section of the rim 10). Here, the inner peripheral surface of the core 11 is the surface on which the spokes 9 are arranged, and the outer peripheral surface of the core 11 is the surface opposite to the inner peripheral surface of the core 11.

[0066] The first insulator 21 has a first surface 21a, which is the surface opposite to the core 11 side, and a second surface 21b on the core 11 side.

[0067] A first electrode 31 is disposed on the first surface 21a, and a second electrode 32 is disposed on the second surface 21b. In other words, the first insulator 21 is sandwiched between the first electrode 31 and the second electrode 32. The first insulator 21 can be disposed in such a manner that the first electrode 31 and the second electrode 32 are spaced apart and overlap each other. In other words, the first insulator 21 can dispose the first electrode 31 and the second electrode 32 so that they are not electrically connected.

[0068] The first insulator 21 is made of a resin material such as a hard plastic, for example, polycarbonate or polybutylene terephthalate.

[0069] Furthermore, a constant thickness is ensured for the first insulator 21. The constant thickness means, for example, that the thickness of the first insulator 21 is about several millimeters. Since the first insulator 21 has a constant thickness, rigidity is ensured.

[0070] Furthermore, the first insulator 21 and the second electrode 32 are supported by the second insulator 22 and are arranged at a predetermined distance from the core metal 11. In other words, the second electrode 32, which is arranged between the first insulator 21 and the second insulator 22, is arranged at a predetermined distance from the core metal 11 by the second insulator 22.

[0071] The second insulator 22 is disposed between the second electrode 32 and the metal core 11. The second insulator 22 overlaps with the first electrode 31, the first insulator 21, and the second electrode 32, and is covered by the first electrode 31, the first insulator 21, and the second electrode 32. The second insulator 22 is disposed along the surface of the metal core 11 while contacting the surface of the metal core 11. In other words, the second insulator 22 can insulate the second electrode 32 from the metal core 11 so that the second electrode 32 and the metal core 11 are not electrically connected to each other.

[0072] The first insulator 21 and the second insulator 22 may be collectively referred to as the insulator. The first insulator 21 and the second insulator 22 are included in the insulator.

[0073] 3, 4, and 5, the second insulator 22 has, in the cross section of the rim 10, a first engaging portion 23a that engages with a first engaged portion 11c1 provided on the core metal 11, and a second engaging portion 23b that engages with a second engaged portion 11c2. The first engaging portion 23a and the second engaging portion 23b are included in the engaging portion.

[0074] 3, first engaging portion 23a engages with first engaged portion 11c1 of core 11. Specifically, first engaging portion 23a can engage with first engaged portion 11c1 by being inserted into first engaged portion 11c1. In other words, first engaging portion 23a has a cylindrical or tubular shape standing upright from the surface of second insulator 22 facing the core 11, and is fixed to first engaged portion 11c1 by being fitted into first engaged portion 11c1.

[0075] Furthermore, first engaging portion 23a is cylindrical or tubular, and has fastening holes 23a1 that correspond to screw holes 11d1 of first engaged portion 11c1. That is, first engaging portion 23a can be fastened to fastening member 19 by inserting fastening member 19, which has passed through screw hole 11d1 of first engaged portion 11c1, into fastening hole 23a1 of first engaging portion 23a.

[0076] 4 and 5, the second engaging portion 23b has an engaging claw 23b1 that engages with the second engaged portion 11c2 of the core metal 11. Specifically, the second engaging portion 23b has the engaging claw 23b1 that is inserted into the insertion hole 11c3 of the second engaged portion 11c2 and can engage with the standing wall 11c4 of the second engaged portion 11c2. The second engaging portion 23b is rod-shaped or plate-shaped and stands upright from the surface of the second insulator 22 facing the core metal 11. When the second engaging portion 23b is inserted into the insertion hole 11c3 of the second engaged portion 11c2, the engaging claw 23b1 of the second engaging portion 23b gets caught on the standing wall 11c4 of the second engaged portion 11c2.

[0077] Furthermore, one or more first engaging portions 23a and one or more second engaging portions 23b are disposed on second insulator 22. Furthermore, according to the number of first engaging portions 23a and second engaging portions 23b, a plurality of first engaged portions 11c1 and a plurality of second engaged portions 11c2 are formed on core metal 11. Furthermore, first engaging portions 23a, second engaging portions 23b, first engaged portions 11c1 and second engaged portions 11c2 may be disposed on rim 10 at approximately equal intervals.

[0078] The second insulator 22 is made of a resin material such as a hard plastic, for example, polycarbonate or polybutylene terephthalate.

[0079] Furthermore, a constant thickness is ensured for the second insulator 22. The constant thickness means, for example, that the thickness of the second insulator 22 is about several millimeters. Since the second insulator 22 has a constant thickness, rigidity is ensured.

[0080] As shown in FIG. 2, the first insulator 21 has a first positioning portion 21t, and the second insulator 22 has a second positioning portion 22t.

[0081] The first positioning portions 21t are formed at corners of both ends of the first insulator 21 extending along the circumferential direction of the core metal 11. The second positioning portions 22t are formed at corners of both ends of the second insulator 22 extending along the circumferential direction of the core metal 11. In the present embodiment, the first positioning portions 21t are recesses that engage with the second positioning portions 22t, but they may also be protrusions that engage with the second positioning portions 22t. The second positioning portions 22t are protrusions that engage with the first positioning portions 21t, but they may also be recesses that engage with the first positioning portions 21t. When the first insulator 21 is assembled to the second insulator 22 while sandwiching the second electrode 32 between the first insulator 21 and the second insulator 22, the first positioning portions 21t and the second positioning portions 22t are engaged with each other. In this way, the first insulator 21 and the second insulator 22 can be aligned, thereby preventing circumferential misalignment between the first insulator 21 and the second insulator 22 and making assembly easy and proper.

[0082] Although the first positioning portions 21t are formed at the corners of the first insulator 21, they may be formed anywhere. Furthermore, a plurality of first positioning portions 21t may be formed on the first insulator 21. Furthermore, although the second positioning portions 22t are formed at the corners of the second insulator 22, they may be formed anywhere. Furthermore, a plurality of second positioning portions 22t may be formed on the second insulator 22. For example, the first positioning portions 21t may be formed at four corners at both end portions of the first insulator 21, and the second positioning portions 22t may be formed at four corners at both end portions of the second insulator 22.

[0083] The first electrode 31 is linear and is disposed on a first surface 21a of the first insulator 21, which is the surface of the steering wheel 1 opposite to the surface on the core metal 11 side.

[0084] The first electrode 31 may have a resin sheet 31a and a conductive wire 31b. That is, the first electrode 31 may use the conductive wire 31b as an electrode.

[0085] The resin sheet 31a is a base material for arranging the conductive wires 31b on one surface thereof. The resin sheet 31a is arranged on the first surface 21a so that the other surface opposite to the one surface thereof is in contact with the first surface 21a of the first insulator 21. The resin sheet 31a is formed according to the size and shape of the first surface 21a of the first insulator 21 so that it can be arranged on the first surface 21a.

[0086] The resin sheet 31a may be made of, for example, polycarbonate (PC), polyethylene terephthalate (PET), nonwoven fabric, a polyethylene (PE) mat, etc. When the resin sheet 31a is a nonwoven fabric or a polyethylene (PE) mat, the first electrode 31 can be disposed along the first surface 21a of the first insulator 21 without forming the first electrode 31.

[0087] When the resin sheet 31a is a nonwoven fabric or a polyethylene mat, the conductive wire 31b may be disposed on one side of the resin sheet 31a opposite to the other side on the first surface 21a side, and sewn thereto with sewing thread. The sewing thread is a thread that sews the conductive wire 31b to the resin sheet 31a along the extending direction of the conductive wire 31b in order to fix the conductive wire 31b to the resin sheet 31a.

[0088] When the conductive wire 31b is arranged on one side of the resin sheet 31a, the distance from the surface of the rim 10 to the conductive wire 31b can be made shorter than when the conductive wire 31b is arranged on the other side of the resin sheet 31a, which improves the sensitivity of detecting grip on the steering wheel 1 and makes it easier to heat the surface of the steering wheel 1. Note that the conductive wire 31b may also be arranged on the other side of the resin sheet 31a.

[0089] As shown in Fig. 7A, the conductor 31b is a metal wire containing copper, aluminum, silver, or the like. The conductor 31b is folded back multiple times and sewn in one piece to one surface of the resin sheet 31a so as to form a zigzag pattern consisting of a line portion and a folded portion along the circumferential direction of the core 11. Note that, as shown in Fig. 7B, for example, the conductor 31b may have a zigzag pattern in which the line portion is substantially parallel and extends in a direction perpendicular to the circumferential direction of the core 11.

[0090] As shown in FIGS. 7A and 7B , the conductive wires 31b are arranged at approximately equal intervals on one side of the resin sheet 31a, but this is not limiting. For example, the conductive wires 31b may be arranged more densely than the standard density in some parts of one side of the resin sheet 31a and more sparsely than the standard density in other parts. That is, the first electrode 31 may have regions where the conductive wires 31b are densely arranged and regions where the conductive wires 31b are sparsely arranged. By arranging the conductive wires 31b densely or sparsely on one side of the resin sheet 31a, it is possible to suppress temperature variations on the surface of the rim 10. Note that, in the case of the conductive wires 31b arranged at approximately equal intervals as shown in FIGS. 7A and 7B , for example, the conductive wires 31b may be arranged more densely than the standard density by narrowing the intervals in some parts. Furthermore, when leather is further wrapped around the surface of the rim 10, the conductive wires 31b may be arranged in regions where they are densely arranged and regions where they are sparsely arranged on one side of the resin sheet 31a to ensure a uniform surface temperature. The standard density is a predetermined density and may be set arbitrarily.

[0091] The first electrode 31 may also include a metal thin film formed by etching or applying it to the resin sheet 31a. For example, the first electrode 31 may have a conductive wire 31b formed by etching or applying it to one surface of the resin sheet 31a, as shown in FIGS. 7A and 7B.

[0092] 2 and 6, the first electrode 31 may be formed by etching or applying metal plating to the first surface 21a of the first insulator 21. In other words, the first electrode 31 may not be provided with the resin sheet 31a.

[0093] Such a first electrode 31 serves both as a sensor electrode that detects gripping of the steering wheel 1 and as a heater wire that heats the steering wheel 1.

[0094] Specifically, the first electrode 31 is used exclusively as a sensor electrode and as a heater wire. That is, the control circuit 40 selectively switches between using the first electrode 31 as a sensor electrode and using it as a heater wire.

[0095] The first electrode 31 may also be a heater wire that heats the steering wheel 1. In other words, the first electrode 31 does not have to be used as a sensor electrode. The first electrode 31 does not have to be used as a heater wire, and may be used only as a sensor electrode.

[0096] When the first electrode 31 is used as a sensor electrode, an AC voltage is applied to the first electrode 31. The AC voltage applied to the first electrode 31 is generated by the control circuit 40 using power supplied from the power supply unit 41. Here, since the first electrode 31 is disposed on the first surface 21a of the first insulator 21, when the driver's hand grips the part of the rim 10 where the first electrode 31 is disposed, a capacitance is formed between the first electrode 31 and the hand. Therefore, the control circuit 40 can detect that the hand is gripping the rim 10 in accordance with the change in capacitance.

[0097] When the first electrode 31 is used as a heater wire, a DC voltage is applied to the first electrode 31. The DC voltage applied to the first electrode 31 is generated by a power supply unit 41. The first electrode 31 generates heat by the power from the power supply unit 41 controlled by a control circuit 40.

[0098] An example will be described in which the first electrode 31 is used exclusively as a sensor electrode and as a heater wire.

[0099] For example, first, an AC voltage is applied to the first electrode 31, and the first electrode 31 is used as a sensor electrode, and then the application of the AC voltage to the first electrode 31 is stopped. After a predetermined time has elapsed since the application of the AC voltage to the first electrode 31 was stopped, a DC voltage is applied to the first electrode 31, and the first electrode 31 is used as a heater wire. Furthermore, the application of the DC voltage to the first electrode 31 is stopped, and after a predetermined time has elapsed, an AC voltage is applied to the first electrode 31, and the first electrode 31 is used as a sensor electrode. To repeat this operation, the first electrode 31 is used exclusively as a sensor electrode and as a heater wire.

[0100] In this way, when the first electrode 31 is repeatedly switched between being used as a sensor electrode and being used as a heater wire, and used exclusively, the time when the first electrode 31 is used as a heater wire may be longer than the time when the first electrode 31 is used as a sensor electrode.

[0101] The second electrode 32 is disposed on the second surface 21b, which is the surface of the first insulator 21 opposite to the first surface 21a. Specifically, the second electrode 32 is disposed along the second surface 21b of the first insulator 21 so as to sandwich the first insulator 21 together with the first electrode 31. The second electrode 32 is sandwiched between the first insulator 21 and the second insulator 22. In other words, the second electrode 32 is disposed apart from the core 11 and the first electrode 31. Therefore, the second electrode 32 is not electrically connected to the core 11 and the first electrode 31.

[0102] The second electrode 32 in this embodiment is made of a metal plate. In this case, the metal plate is attached to the second surface 21b of the first insulator 21 with an adhesive or the like. The second electrode 32 is made of a metal containing, for example, copper, aluminum, or silver.

[0103] The second electrode 32 may also be composed of a resin sheet and a metal thin film arranged on one side of the resin sheet on the second surface 21b side, or the second electrode 32 may be composed of a metal sheet.

[0104] The resin sheet of the second electrode 32 is a base material for disposing on one surface a thin metal film or a metal sheet of the second electrode 32. The resin sheet of the second electrode 32 is disposed on the second surface 21b of the first insulator 21 so that the other surface opposite to the one surface is in contact with the second surface 21b of the first insulator 21. The resin sheet of the second electrode 32 is formed according to the size and shape of the second surface 21b of the first insulator 21 so that it can be disposed on the second surface 21b.

[0105] The resin sheet of the second electrode 32 may be made of, for example, nonwoven fabric, etc. In this case, the second electrode 32 can be arranged along the second surface 21b of the first insulator 21 without forming the second electrode 32.

[0106] The second electrode 32 may be made of a metal thin film formed by etching or applying it to a resin sheet. For example, the metal thin film of the second electrode 32 may be formed by etching or applying it to one surface of a resin sheet.

[0107] The second electrode 32 may be formed by etching or applying metal plating to the second surface 21b of the first insulator 21.

[0108] When the first electrode 31 and the second electrode 32 are formed by metal plating, because the hole 22f is formed in the second insulator 22 at the base of the second engaging portion 23b, the hole 22f of the second insulator 22 is masked, and the first surface 21a of the first insulator 21 at a location corresponding to the hole 22f is also masked. This allows the second electrode 32 to be formed on the surface of the second insulator 22 facing the first insulator 21, excluding the hole 22f, and the first electrode 31 to be formed on the first surface 21a of the first insulator 21, excluding the location corresponding to the hole 22f. In other words, the second electrode 32 is not formed in the hole 22f of the second insulator 22, and the first electrode 31 is not formed on the first surface 21a of the first insulator 21 at a location corresponding to the hole 22f. Alternatively, the first electrode 31 may be formed by metal plating the first surface 21a of the first insulator 21, and the second electrode 32 may be formed by metal plating the second surface 21b of the first insulator 21.

[0109] When assembling the first electrode 31 to the first insulator 21, if the resin sheet 31a of the first electrode 31 is a resin film such as polycarbonate, the first electrode 31 is subjected to forming processing. As a result, the first electrode 31 is formed to fit the shape of the first surface 21a of the first insulator 21. The first electrode 31 after processing is placed on the first surface 21a of the first insulator 21.

[0110] When assembling the second electrode 32 to the first insulator 21, if the second electrode 32 is a metal sheet, if the second electrode 32 is a metal plate, or if the resin sheet of the second electrode 32 is a resin film, the second electrode 32 is subjected to forming processing. As a result, the second electrode 32 is formed to fit the shape of the second surface 21b of the first insulator 21. The processed second electrode 32 is placed on the second surface 21b of the first insulator 21.

[0111] Furthermore, when the first electrode 31 and the second electrode 32 are viewed overlapping each other, the first electrode 31 is entirely covered by the second electrode 32, and the surface area of ​​the second electrode 32 arranged on the second surface 21b is larger than the surface area of ​​the first electrode 31 arranged on the first surface 21a. Therefore, the second electrode 32 can suppress the formation of electrostatic capacitance between the first electrode 31 and the cored bar 11.

[0112] One end of the first electrode 31 is electrically connected to the harness 8a, and the other end of the first electrode 31 is electrically connected to the harness 8c. The second electrode 32 is electrically connected to the harness 8b.

[0113] The harness 8a and the first electrode 31 may be electrically connected by soldering one end of the harness 8a and the first electrode 31. Alternatively, the harness 8a and the first electrode 31 may be electrically connected by crimping one end of the harness 8a and the first electrode 31 with a rivet. Alternatively, the harness 8c and the first electrode 31 may be electrically connected by soldering the other end of the harness 8c and the first electrode 31. Alternatively, the harness 8c and the first electrode 31 may be electrically connected by crimping the other end of the harness 8c and the first electrode 31 with a rivet.

[0114] Alternatively, the harness 8b and the second electrode 32 may be electrically connected to each other by soldering them together. Alternatively, the harness 8b and the second electrode 32 may be electrically connected to each other by crimping them together with a rivet.

[0115] These harnesses 8 a , 8 b , and 8 c are electrically connected to a control circuit 40 .

[0116] The control circuit 40 can apply an AC voltage to the first electrode 31 and the second electrode 32 via the harnesses 8a, 8b, and 8c. The control circuit 40 can apply the AC voltage generated by the power supply unit 41 to the first electrode 31 and the second electrode 32 via the harnesses 8a, 8b, and 8c. By applying AC voltages of the same phase to the first electrode 31 and the second electrode 32, the capacitance formed between the first electrode 31 and the core metal 11 can be canceled or reduced. Therefore, the control circuit 40 can accurately detect the capacitance formed between the first electrode 31 and the driver's hand.

[0117] Furthermore, when the first electrode 31 is used as a heater wire for heating the steering wheel 1, the control circuit 40 can apply a DC voltage to the first electrode 31 via the harnesses 8a and 8c. The control circuit 40 can apply a DC voltage generated by the power supply unit 41 to the first electrode 31 via the harnesses 8a and 8c. Therefore, the first electrode 31 generates heat by the power from the power supply unit 41 controlled by the control circuit 40, and can heat the steering wheel 1.

[0118] In addition, the first insulator 21, the second insulator 22, the first electrode 31, and the second electrode 32 are arranged in the cross section of the rim 10 of the steering wheel 1 in a range from at least the outer peripheral portion of the rim 10 of the steering wheel 1 to the rear portion of the rim 10 of the vehicle 3.

[0119] In this embodiment, the first insulator 21, the second insulator 22, the first electrode 31, and the second electrode 32 are arranged over at least a quarter of the circumference of the rim 10 in the circumferential direction. As shown in FIG. 3 , the first insulator 21, the first electrode 31, and the second electrode 32 are arranged over a range larger than the range L between two straight lines V1 and V2 indicated by the two-dot chain lines. Specifically, the first insulator 21, the second insulator 22, the first electrode 31, and the second electrode 32 are arranged from the first portion 11a of the rim 10, via the curved portion 11c, to the second portion 11b. In this way, the first insulator 21, the first electrode 31, and the second electrode 32 are arranged at locations that are likely to come into contact with the driver's hands when gripping the rim 10. This allows the electrode structure 20 to accurately detect whether the driver's hands are gripping the steering wheel 1.

[0120] [Foam 15] As shown in FIG. 2 , foam 15 is the portion that is gripped by the driver's hands and constitutes the outer shell of rim 10 of steering wheel 1. Foam 15 is made of a resin material, such as a urethane resin, such as polyurethane, and covers electrode structure 20. Foam 15 embeds first insulator 21, second insulator 22, first electrode 31, second electrode 32, and core 11. In other words, first insulator 21, second insulator 22, first electrode 31, second electrode 32, and core 11 are covered by foam 15.

[0121] <Method of manufacturing the steering wheel 1> FIG. 8 is a flowchart showing a method for manufacturing the steering wheel 1 according to the embodiment.

[0122] 8, an operator prepares a metal core 11 and an electrode structure 20. Then, an engaging portion of the electrode structure 20 is engaged with an engaged portion of the metal core 11, and fastening members 19 are inserted into fastening holes 23a1 to fasten the engaging portion to the metal core 11, thereby assembling the electrode structure 20 to the metal core 11 (S11: assembling step). Specifically, the first engaged portion 11c1 of the metal core 11 is engaged with the first engaging portion 23a of the second insulator 22. That is, the first engaging portion 23a is engaged with the first engaged portion 11c1, and the first engaging portion 23a is fastened to the first engaged portion 11c1 by the fastening members 19 inserted into the screw holes 11d1 of the first engaged portion 11c1 and the fastening holes 23a1 of the first engaging portion 23a. Further, the second engaged portion 11c2 of the core metal 11 engages with the second engaging portion 23b of the second insulator 22. That is, the engaging claw 23b1 of the second engaging portion 23b provided on the electrode structure 20 is engaged with the second engaged portion 11c2 provided on the core metal 11. This results in a structure in which the electrode structure 20 is fastened to the core metal 11.

[0123] Next, the structure is fixed in a mold cavity, and the mold is clamped. An injection molding resin is poured into the mold cavity through a gate formed in the mold (S12: injection step), thereby forming a foam 15 that covers the structure in which the electrode structure 20 and the core metal 11 are fastened together. The injection molding resin is a resin material such as a urethane resin such as polyurethane.

[0124] This allows the foam 15 to cover the electrode structure 20 and the core metal 11 in a state in which the electrode structure 20 is engaged with the core metal 11. In this way, the steering wheel 1 can be obtained.

[0125] <Action and effect> The effects of the electrode structure 20, the steering wheel 1, and the method for manufacturing the steering wheel 1 according to this embodiment will be described.

[0126] As described above, the electrode structure 20 according to this embodiment is an electrode structure 20 disposed along the outer periphery of the metal core 11 of the steering wheel 1 provided in the vehicle 3, and includes an insulator (first insulator 21 and second insulator 22) and a linear first electrode 31 disposed on the first surface 21a, which is the surface of the insulator opposite to the surface facing the metal core 11. The insulator has an engaging portion (first engaging portion 23a and / or second engaging portion 23b) that engages with the metal core 11.

[0127] This allows the electrode structure 20 to be attached to the core metal 11 in advance. This allows the electrode structure 20 to be disposed inside the steering wheel 1 when the steering wheel 1 is formed. Therefore, unlike the prior art, it is not necessary to form the steering wheel and then cut a cut in the steering wheel to dispose the first electrode therein.

[0128] Therefore, the electrode structure 20 can prevent the manufacturing cost from rising while ensuring the appearance of the steering wheel 1.

[0129] In the electrode structure 20 according to this embodiment, the first electrode 31 serves both as a sensor electrode that detects gripping of the steering wheel 1 and as a heater wire that heats the steering wheel 1.

[0130] According to this, the first electrode 31 can serve as both a sensor electrode and a heater wire, eliminating the need to provide a separate heater wire in the steering wheel 1. This makes it possible to prevent an increase in the manufacturing costs of the steering wheel 1 to which the electrode structure 20 is applied.

[0131] In the electrode structure 20 according to this embodiment, the first electrode 31 is a heater wire that heats the steering wheel 1.

[0132] According to this, the linear first electrode 31 provided on the electrode structure 20 attached to the core metal 11 can heat the steering wheel 1.

[0133] In the electrode structure 20 according to this embodiment, the first electrode 31 is a sensor electrode that detects whether the steering wheel 1 is being gripped.

[0134] According to this, the linear first electrode 31 provided on the electrode structure 20 attached to the core metal 11 can detect whether the steering wheel 1 is being gripped.

[0135] The electrode structure 20 according to this embodiment also includes a second electrode 32 disposed on a second surface 21b of the insulator, which is the surface opposite to the first surface 21a.

[0136] This allows the electrode structure 20 including the second electrode 32 to be attached to the core metal 11 in advance. This allows the electrode structure 20 to be disposed inside the steering wheel 1 when the steering wheel 1 is formed. Therefore, unlike the prior art, it is not necessary to form the steering wheel and then cut a cut in the steering wheel to dispose the second electrode therein.

[0137] Moreover, the steering wheel 1 according to this embodiment includes an electrode structure 20, a metal core 11, and a foam body 15 that covers the metal core 11.

[0138] This steering wheel 1 also provides the same effects as those described above.

[0139] In addition, the manufacturing method of the steering wheel 1 according to this embodiment involves engaging the engaging portion of the electrode structure 20 of the steering wheel 1 with the engaged portion (first engaged portion 11c1 and / or second engaged portion 11c2) provided on the core wire 11, and covering the core wire 11 with foam 15 while the engaging portion is engaged with the engaged portion.

[0140] According to this, by engaging the engaging portion with the engaged portion of the core metal 11, the electrode structure 20 and the core metal 11 can be firmly fastened together. This makes it possible to prevent the insulator from being displaced relative to the core metal 11 or from being rotated in the circumferential direction of the steering wheel 1 due to the pressure applied when the steering wheel 1 is resin-molded. This manufacturing method for the steering wheel 1 also achieves the same effects as those described above.

[0141] Furthermore, in the electrode structure 20 according to this embodiment, in a cross section of the steering wheel 1 cut along a plane perpendicular to the circumferential direction of the steering wheel 1, the first electrode 31 is formed along the shape of the first surface 21a of the insulator, and the second electrode 32 is formed along the shape of the second surface 21b of the insulator.

[0142] This allows the distance between the first electrode 31 and the second electrode 32 to be made uniform, so that accurate detection is possible regardless of which part of the steering wheel 1 the driver is holding with his or her hand in the area where the electrode structure 20 is installed.

[0143] In the electrode structure 20 according to this embodiment, the insulators include a first insulator 21 and a second insulator 22. The first insulator 21 has a first surface 21a and a second surface 21b. The first electrode 31 is disposed on the first surface 21a of the first insulator 21. The second electrode 32 is disposed on the second surface 21b, which is the surface of the first insulator 21 opposite to the first surface 21a. The second insulator 22 is disposed between the second electrode 32 and the core 11. The second insulator 22 has an engaging portion that engages with the core 11.

[0144] This allows the second insulator 22 to position the second electrode 32 in a state spaced apart from the core 11, and the first insulator 21 to position the first electrode 31 in a state spaced apart from the second electrode 32 and the core 11. Furthermore, because the first electrode 31 and the second electrode 32 can be positioned on the first insulator 21, a member in which the first insulator 21, the first electrode 31, and the second electrode 32 are integrated can be easily assembled to the core 11.

[0145] In addition, in the electrode structure 20 of this embodiment, the first insulator 21, the second insulator 22, the first electrode 31, and the second electrode 32 are arranged in a range from at least the outer periphery of the steering wheel 1 to the inner periphery of the steering wheel 1 in a cross section of the steering wheel 1 cut along a plane perpendicular to the circumferential direction of the steering wheel 1.

[0146] According to this, when the driver's hands grip the steering wheel 1, the electrode structure 20 can be arranged in a position where the driver's hands are likely to come into contact with the surface of the steering wheel 1. Therefore, it is possible to detect that the driver's hands are gripping the steering wheel 1.

[0147] In the electrode structure 20 according to this embodiment, the first insulator 21 is made of a resin material. The second insulator 22 is made of a resin material. The first electrode 31 includes metal plating or a metal thin film. The second electrode 32 includes metal plating, a metal thin film, a metal sheet, or a metal plate.

[0148] This allows the first electrode 31 and the second electrode 32 to be arranged on the first insulator 21, and therefore makes it possible to easily assemble a member in which the first insulator 21, the second insulator 22, the first electrode 31, and the second electrode 32 are integrated to the core 11. Furthermore, since the second insulator 22 is arranged between the first insulator 21 and the second electrode 32 and the core 11, the second insulator 22 allows the first electrode 31 to be arranged in a state separated from the core 11.

[0149] In the electrode structure 20 according to this embodiment, the first insulator 21 is made of a resin material. The second insulator 22 is also made of a resin material. The first electrode 31 has a resin sheet 31a and a conductive wire 31b. The conductive wire 31b is disposed on the surface of the resin sheet 31a opposite to the surface on the first surface 21a side, and is sewn with sewing thread. The second electrode 32 is configured to include metal plating, a metal thin film, a metal sheet, or a metal plate.

[0150] According to this, when the first electrode 31 is disposed on the first surface 21a of the first insulator 21 and the second electrode 32 is disposed on the second surface 21b of the first insulator 21, the resin sheet 31a is made of a soft material to which the conductor 31b can be sewn with sewing thread, and therefore the first electrode 31 and the second electrode 32 can be easily disposed to follow the shape of the first insulator 21 without performing a forming process along the shapes of the first surface 21a and the second surface 21b. Therefore, an increase in the number of steps required to dispose the first electrode 31 on the first surface 21a of the first insulator 21 and the second electrode 32 on the second surface 21b of the first insulator 21 can be suppressed.

[0151] In the electrode structure 20 according to this embodiment, the first insulator 21 has a first positioning portion 21t, and the second insulator 22 has a second positioning portion 22t that engages with the first positioning portion 21t.

[0152] This allows the first positioning portion 21t and the second positioning portion 22t to mesh together when assembling the first insulator 21 to the second insulator 22. This allows the first insulator 21 and the second insulator 22 to be aligned, thereby preventing misalignment between the first insulator 21 and the second insulator 22 in the circumferential direction and making the assembling easy and appropriate.

[0153] In the electrode structure 20 according to this embodiment, the first electrode 31 is used exclusively as a sensor electrode and as a heater wire.

[0154] According to this, for example, when driving the vehicle 3 in a cold region, not only can the steering wheel 1 be warmed by turning on the heater function and supplying power to the first electrode (heater wire), but it can also detect whether the driver is gripping the steering wheel 1.

[0155] Furthermore, in the electrode structure 20 according to this embodiment, when the first electrode 31 is used as a sensor electrode, an AC voltage having the same phase as the AC voltage applied to the second electrode 32 is applied to the first electrode 31.

[0156] This makes it possible to cancel or reduce the capacitance formed between the first electrode 31 and the core metal 11 when the first electrode 31 is used as a sensor electrode. Therefore, by using a control circuit 40 that detects the driver's gripping of the steering wheel 1, the control circuit 40 can accurately detect the capacitance formed between the first electrode 31 and the driver's hand when the driver's hand grips the steering wheel 1.

[0157] Furthermore, in the electrode structure 20 according to this embodiment, the engaging portion (first engaging portion 23a and / or second engaging portion 23b) engages with the engaged portion (first engaged portion 11c1 and / or second engaged portion 11c2) provided on the core metal 11.

[0158] According to this, in this electrode structure 20, the engaged portion and the engaging portion engage with each other, thereby ensuring the distance between the first electrode 31 and the insulator and maintaining the posture at the same time. Therefore, the electrode structure 20 can be incorporated into the steering wheel 1 when the steering wheel 1 is molded from resin.

[0159] Furthermore, simply by engaging the engaged portion with the engaging portion, the first insulator 21 can position the first electrode 31 and the second electrode 32 in a state spaced apart from the core wire 11, and the component in which the first insulator 21 and the first electrode 31 are integrated can be easily assembled to the core wire 11.

[0160] Furthermore, the engagement between the engaged portion and the engaging portion allows the electrode structure 20 to be firmly fastened to the core metal 11. This prevents the insulator from being displaced relative to the core metal 11 or from being rotated in the circumferential direction of the steering wheel 1 due to the pressure applied during resin molding of the steering wheel 1. As a result, it is possible to prevent an increase in the number of steps required for manufacturing the steering wheel 1 and to prevent a rise in manufacturing costs.

[0161] (First Modification of the Embodiment) The electrode structure 120 and steering wheel 1a of this modification differ from the electrode structure and steering wheel of the embodiment in that they have a first insulator 21, a first electrode 31, and a second electrode 32, but do not have a second insulator. In this modification, the same components and functions as those of the electrode structure and steering wheel of the embodiment are denoted by the same reference numerals, and detailed descriptions of these components and functions will be omitted as appropriate.

[0162] First, the configuration of the steering wheel 1a will be described with reference to FIGS.

[0163] Fig. 9 is a perspective view showing a steering wheel 1a according to a first modified example of the embodiment and a cross-sectional view of the core metal 11. Fig. 10 is a cross-sectional view showing the first engaged portion 11c1 and the first engaging portion 23a of the steering wheel 1a taken along line CC in Fig. 9. Fig. 11 is a cross-sectional view showing the second engaged portion 11c2 and the second engaging portion 23b of the steering wheel 1a.

[0164] As shown in FIGS. 9 to 11, an electrode structure 120 of this modified example includes a first insulator 21, a first electrode 31, a second electrode 32, and a protrusion 21d.

[0165] The first insulator 21 is disposed along the surface from the outer circumferential side to the inner circumferential side of the core 11. The first insulator 21 has a first surface 21a, which is the surface opposite to the core 11 side, and a second surface 21b on the core 11 side. A first electrode 31 is disposed on the first surface 21a, and a second electrode 32 is disposed on the second surface 21b. The second surface 21b is located at a predetermined distance from the core 11 by a protrusion 21d. Therefore, the second electrode 32 disposed on the second surface 21b is disposed at a distance from the core 11. In addition, since the foam 15 is disposed between the second electrode 32 and the core 11 during the injection process, the second electrode 32 is not electrically connected to the core 11.

[0166] Such a first insulator 21 allows the first electrode 31 and the second electrode 32 to be arranged spaced apart from each other so that the first electrode 31 and the second electrode 32, and the second electrode 32 and the core 11, are not electrically connected.

[0167] In addition, the first insulator 21 has, in a cross section of the steering wheel 1a cut along a plane perpendicular to the circumferential direction of the steering wheel 1a, a first engaging portion 23a that engages with a first engaged portion 11c1 provided on the core wire 11, and a second engaging portion 23b that engages with a second engaged portion 11c2 provided on the core wire 11.

[0168] First engaging portion 23a can engage with first engaged portion 11c1 by being inserted into first engaged portion 11c1. That is, first engaging portion 23a has a cylindrical or tubular shape standing upright from second surface 21b of first insulator 21, and is fixed to first engaged portion 11c1 by being fitted into first engaged portion 11c1.

[0169] Furthermore, first engaging portion 23a is cylindrical or tubular, and has fastening hole 23a1 corresponding to screw hole 11d1 of first engaged portion 11c1. That is, first engaging portion 23a can be fastened to fastening member 19 by inserting fastening member 19, which has passed through screw hole 11d1 of first engaged portion 11c1, into fastening hole 23a1 of first engaging portion 23a.

[0170] The second engaging portion 23b has an engaging claw 23b1 that engages with the second engaged portion 11c2 of the core metal 11. Specifically, the second engaging portion 23b has the engaging claw 23b1 that is inserted into the insertion hole 11c3 of the second engaged portion 11c2 and can engage with the standing wall 11c4 of the second engaged portion 11c2. In other words, the second engaging portion 23b is rod-shaped or plate-shaped and stands upright from the second surface 21b of the first insulator 21. When the second engaging portion 23b is inserted into the insertion hole 11c3 of the second engaged portion 11c2, the engaging claw 23b1 of the second engaging portion 23b gets caught on the standing wall 11c4 of the second engaged portion 11c2.

[0171] Protrusion 21d is disposed at a position on first insulator 21 facing core 11. Protrusion 21d also protrudes from first insulator 21 toward core 11. A portion of the tip of protrusion 21d abuts against core 11. In other words, protrusion 21d is disposed between first insulator 21 and core 11. Therefore, protrusion 21d can ensure the distance of second electrode 32 from core 11 and maintain its posture so that first insulator 21 and second electrode 32 do not come into contact with core 11.

[0172] Moreover, the protrusion 21d is formed integrally with the first insulator 21. Note that the protrusion 21d may be a separate body that can be separated from the first insulator 21.

[0173] Furthermore, a plurality of protrusions 21d are arranged between the core metal 11 and the first insulator 21. Furthermore, the protrusions 21d may be arranged on the core metal 11 and the first insulator 21 at approximately equal intervals.

[0174] The first electrode 31 is disposed on a first surface 21a of the first insulator 21, which is the surface opposite to the surface of the steering wheel 1a on the core metal 11 side.

[0175] The electrode structure 120 of this modified example also provides the same effects as those of the embodiment.

[0176] (Modification 2 of the embodiment) The electrode structure 220 and steering wheel 1b of this modification differ from the electrode structure and steering wheel of the embodiment in that they have a first insulator 21, a first electrode 31, and a second electrode 32, but no second insulator, and in that the second electrode 32 is not arranged on the second surface 21b, but the first electrode 31 is arranged on one surface of the resin sheet 33, and the second electrode 32 is arranged on the other surface of the resin sheet 33. Furthermore, the configurations of the first insulator 21 and the protrusion 21d are similar to those of the first insulator of the first modification of the embodiment. In this modification, the same components and functions as those of the electrode structure and steering wheel of the embodiment and the first modification of the embodiment are denoted by the same reference numerals, and detailed descriptions of these components and functions will be omitted as appropriate.

[0177] First, the configuration of the steering wheel 1b will be described with reference to FIGS.

[0178] Fig. 12 is a cross-sectional view showing the first engaged portion 11c1 and the first engaging portion 23a of the steering wheel 1b, and Fig. 13 is a cross-sectional view showing the second engaged portion 11c2 and the second engaging portion 23b of the steering wheel 1b.

[0179] As shown in FIGS. 12 and 13, the electrode structure 220 of this modification includes a resin sheet 33, a first electrode 31, and a second electrode 32 in addition to the first insulator 21 and the protruding portion 21d.

[0180] The resin sheet 33 is a base material for disposing the first electrode 31 on one surface 33a and disposing the second electrode 32 on the other surface 33b, which is the back surface of the one surface 33a. The resin sheet 33 is disposed on the first surface 21a of the first insulator 21 so that the other surface 33b faces the first surface 21a of the first insulator 21 with the second electrode 32 interposed therebetween.

[0181] The resin sheet 33 may be made of, for example, polycarbonate (PC), polyethylene terephthalate (PET), nonwoven fabric, or a polyethylene (PE) mat.

[0182] The first electrode 31 is disposed on one surface 33a of the resin sheet 33. The first electrode 31 is a linear electrode having a zigzag pattern formed on the one surface 33a of the resin sheet 33. The first electrode 31 may be made of a conductive wire or a thin film metal. The first electrode 31 of this modification is a thin film metal formed by etching or applying it to the one surface 33a of the resin sheet 33.

[0183] The second electrode 32 is disposed on the surface on the first surface 21a side, that is, on the other surface 33b of the resin sheet 33. The second electrode 32 is a solid electrode formed on the other surface 33b of the resin sheet 33. The second electrode 32 may be made of a thin metal film or a metal sheet. The second electrode 32 of this modification is a thin metal film formed by etching or applying it to the other surface 33b of the resin sheet 33.

[0184] A structure in which a first electrode 31 is arranged on one side 33a of the resin sheet 33 and a second electrode 32 is arranged on the other side 33b of the resin sheet 33 is attached to the first side 21a of the first insulator 21 with an adhesive or the like so that the second electrode 32 faces the first side 21a.

[0185] The electrode structure 220 according to this modification is disposed along the outer periphery of the metal core 11 of the steering wheel 1b provided in the vehicle 3, and includes a first insulator 21, a resin sheet 33 disposed on a first surface 21a of the first insulator 21 opposite to the metal core 11 side, a linear first electrode 31 disposed on one surface 33a of the resin sheet 33, and a second electrode 32 disposed on the other surface 33b of the resin sheet 33, which is the surface on the first surface 21a side and behind the one surface 33a. The first insulator 21 has an engaging portion (the first engaging portion 23a and / or the second engaging portion 23b) that engages with the metal core 11. The first electrode 31 serves both as a sensor electrode that detects gripping of the steering wheel 1b and as a heater wire that heats the steering wheel 1b.

[0186] This allows the first electrode 31 to be arranged on one surface 33a of one resin sheet 33, and the second electrode 32 to be arranged on the other surface 33b. Therefore, compared to when resin sheets are used for both the first electrode and the second electrode, the electrode structure 220 of this embodiment can suppress an increase in the number of parts, thereby suppressing a rise in manufacturing costs. Furthermore, this electrode structure 220 also achieves the same effects as those described above.

[0187] (Third Modification of the Embodiment) The electrode structure 320 and steering wheel 1c of this modification differ from the electrode structure and steering wheel of the embodiment in that the electrode structure 320 includes a first electrode 31, but does not include a second electrode or a second insulator, and that the first electrode 31 is disposed at an equal distance from the surface 315a of the foam 315. In this modification, the same components and functions as those of the electrode structure and steering wheel of the embodiment and modifications 1 and 2 of the embodiment are denoted by the same reference numerals, and detailed descriptions of these components and functions will be omitted as appropriate.

[0188] FIG. 14 is a cross-sectional view showing the first engaged portion 11c1 and the first engaging portion 23a of the steering wheel 1c.

[0189] As shown in FIG. 14, a rim 10c of a steering wheel 1c of this modified example includes a core metal 11, an electrode structure 320, and a foam body 315 that covers the electrode structure 320.

[0190] In this modification, the first electrode 31 is disposed at a uniform distance from the surface 315a of the foam 315. In other words, the foam 315 has a portion where the thickness from the first electrode 31 to the surface 315a of the foam 315 is substantially uniform. This allows the first electrode 31 to be disposed at a substantially uniform distance from the surface 315a of the foam 315. This reduces variations in detection sensitivity depending on the grip position on the steering wheel 1c, making it possible to detect gripping of the steering wheel 1c at a location corresponding to the first electrode 31. Furthermore, when the first electrode 31 is used as a heater wire, it is possible to reduce variations in temperature on the surface of the rim 10c and substantially uniformize the temperature of the surface of the steering wheel 1c corresponding to the first electrode 31.

[0191] Furthermore, even if the thickness from the first electrode 31 to the surface 315a of the foam 315 is substantially uniform, the conductive wires 31b of the first electrode 31 may be arranged more densely than the standard density in some parts on one side of the resin sheet 31a and more sparsely than the standard density in other parts. The standard density is a preset density and may be set arbitrarily. In addition to the foam 315 having a substantially uniform thickness and the conductive wires 31b being uniformly arranged on one side of the resin sheet 31a, by forming regions on one side of the resin sheet 31a where the conductive wires 31b are densely arranged and regions where they are sparsely arranged, the temperature of the surface of the rim 10 can be made more uniform.

[0192] The electrode structure 320 includes a first insulator 21, a first electrode 31, and a protrusion. The first electrode 31 of this modification may serve both as a sensor electrode that detects gripping of the steering wheel 1c and as a heater wire that heats the steering wheel 1c. The first electrode 31 does not have to be used as a sensor electrode, and may be a heater wire that heats the steering wheel 1c. The first electrode 31 does not have to be used as a heater wire, and may be used only as a sensor electrode.

[0193] (Other variations) The electrode structure, steering wheel, and steering wheel manufacturing method according to the present disclosure have been described above based on the above-mentioned embodiments, but the present disclosure is not limited to these embodiments. As long as they do not deviate from the spirit of the present disclosure, various modifications that would occur to those skilled in the art may also be included in the scope of the present disclosure.

[0194] For example, in the electrode structure, steering wheel, and steering wheel manufacturing method according to the above embodiments, the core metal may not have a first engaged portion but may have a second engaged portion. In this case, the electrode structure may not have a first engaging portion but may have a second engaging portion. Alternatively, the core metal may not have a second engaged portion but may have a first engaged portion. In this case, the electrode structure may not have a second engaging portion but may have a first engaging portion.

[0195] In the electrode structure, steering wheel, and steering wheel manufacturing method according to the above embodiments, the electrode structures may be connected to each other along the circumferential direction of the core. For example, a connecting portion of one electrode structure may be connected to a connected portion of an insulator of another electrode structure adjacent to the electrode structure. In this case, the harness may be electrically connected to each of the multiple first electrodes and the multiple second electrodes individually.

[0196] In the electrode structure, steering wheel, and steering wheel manufacturing method according to the above-described embodiments, the core may be inverted so as to be plane-symmetrical with respect to the opening surface on the inner periphery of the core, and the attachment position of the electrode structure attached to the core may be inverted. That is, the core may be fixed to the spokes so that the opening of the recess in the core faces the driver's seat. Also, the electrode structure may be attached to the front side of the vehicle so as to cover the recess in the core.

[0197] In the electrode structure, steering wheel, and steering wheel manufacturing method according to the above-described embodiment, the steering wheel may further include a control circuit.

[0198] Furthermore, in the electrode structure, steering wheel, and steering wheel manufacturing method according to the above-described embodiment, the embodiment and variants 1 and 2 of the embodiment may be combined in any manner, and are not limited to the aspects disclosed in the present embodiment and variants 1 and 2 of the embodiment.

[0199] In addition, this disclosure also includes forms obtained by making various modifications to the above embodiments that a person skilled in the art would think of, and forms realized by arbitrarily combining the components and functions of the embodiments within the scope of this disclosure.

[0200] (Addendum) <Technology 1> An electrode structure disposed along the outer periphery of a core metal of a steering wheel provided in a vehicle, An insulator; a linear first electrode disposed on a first surface of the insulator opposite to the surface of the insulator facing the core metal; The insulator has an engaging portion that engages with the core metal. Electrode structure.

[0201] <Technology 2> The first electrode serves as both a sensor electrode for detecting gripping of the steering wheel and a heater wire for heating the steering wheel. The electrode structure according to claim 1.

[0202] <Technology 3> The first electrode is a heater wire that heats the steering wheel. The electrode structure according to claim 1.

[0203] <Technology 4> The first electrode is a sensor electrode that detects gripping of the steering wheel. The electrode structure according to claim 1.

[0204] <Technology 5> a second electrode disposed on a second surface of the insulator opposite to the first surface; The electrode structure according to claim 2.

[0205] <Technology 6> In a cross section of the steering wheel taken along a plane perpendicular to the circumferential direction of the steering wheel, the first electrode is formed along the shape of the first surface of the insulator, the second electrode is formed along the shape of the second surface of the insulator. The electrode structure according to claim 5.

[0206] <Technology 7> the insulator includes a first insulator and a second insulator; the first insulator has the first surface and the second surface formed thereon; the first electrode is disposed on the first surface of the first insulator; the second electrode is disposed on the second surface of the first insulator, the second surface being the surface opposite to the first surface; The second insulator is disposed between the second electrode and the core; The engaging portion engages with the core metal. The electrode structure according to claim 5.

[0207] <Technology 8> the first insulator, the second insulator, the first electrode, and the second electrode are arranged in a range from at least an outer circumferential side of the steering wheel to an inner circumferential side of the steering wheel in a cross section of the steering wheel taken along a plane perpendicular to the circumferential direction of the steering wheel. The electrode structure according to claim 7.

[0208] <Technology 9> the first insulator is made of a resin material; the second insulator is made of a resin material, the first electrode is formed by metal plating or by a metal thin film; The second electrode includes a metal plating, a metal thin film, a metal sheet, or a metal plate. The electrode structure according to any one of claims 7 to 8.

[0209] <Technology 10> the first insulator is made of a resin material; the second insulator is made of a resin material, the first electrode includes a resin sheet and a conductive wire; the conductive wire is disposed on a surface of the resin sheet opposite to the surface on the first surface side, and sewn with sewing thread; The second electrode includes a metal plating, a metal thin film, a metal sheet, or a metal plate. The electrode structure according to any one of claims 7 to 8.

[0210] <Technology 11> the first insulator has a first positioning portion, the second insulator has a second positioning portion that engages with the first positioning portion; The electrode structure according to any one of techniques 7 to 10.

[0211] <Technology 12> An electrode structure disposed along the outer periphery of a core metal of a steering wheel provided in a vehicle, a first insulator; a resin sheet disposed on a first surface of the first insulator, the first surface being the surface opposite to the surface of the first insulator facing the core; a linear first electrode disposed on one surface of the resin sheet; a second electrode disposed on the other surface of the resin sheet, the other surface being the backside of the one surface of the resin sheet, the second electrode being on the first surface side; the first insulator has an engaging portion that engages with the core metal, The first electrode serves as both a sensor electrode for detecting gripping of the steering wheel and a heater wire for heating the steering wheel. Electrode structure.

[0212] <Technology 13> The first electrode is used exclusively as the sensor electrode and as the heater wire. The electrode structure according to any one of techniques 2 and 5 to 12.

[0213] <Technology 14> When the first electrode is used as the sensor electrode, an AC voltage having the same phase as an AC voltage applied to the second electrode is applied to the first electrode. The electrode structure according to any one of Techniques 5 to 13.

[0214] <Technology 15> The engaging portion is engaged with an engaged portion provided on the core metal. The electrode structure according to any one of the first to fourth aspects.

[0215] <Technology 16> An electrode structure according to any one of techniques 1 to 15, The core metal; and a foam covering the core metal. Steering wheel.

[0216] <Technology 17> The electrode structure of the steering wheel according to the sixth aspect of the present invention is provided with an engaging portion that is engaged with an engaged portion provided on the core metal. the core metal is covered with the foam in a state where the engaging portion is engaged with the engaged portion; A method for manufacturing a steering wheel. [Industrial Applicability]

[0217] The electrode structure, steering wheel, and steering wheel manufacturing method of the present disclosure are applicable to, for example, vehicle steering wheels. [Explanation of symbols]

[0218] 1, 1a, 1b, 1c steering wheel 3 vehicles 11 Core 11c1 First engaged part 11c2 Second engaged part 15, 315 foam 20, 120, 220, 320 electrode structures 21 First insulator (insulator) 21a 1st page 21b 2nd side 21t First positioning part 22t Second positioning part 22 Second insulator (insulator) 23a First engagement portion (engagement portion) 23b Second engaging part (engaging part) 31 1st electrode 31a, 33 Resin sheet 31b Conductor 32 2nd electrode 33a One side of the resin sheet 33b Other side of resin sheet

Claims

1. An electrode structure disposed along the outer periphery of a core metal of a steering wheel provided in a vehicle, An insulator; a linear first electrode disposed on a first surface of the insulator opposite to the surface of the insulator facing the core metal; The insulator has an engaging portion that engages with the core metal. Electrode structure.

2. The first electrode serves as both a sensor electrode for detecting gripping of the steering wheel and a heater wire for heating the steering wheel. The electrode structure of claim 1 .

3. The first electrode is a heater wire that heats the steering wheel. The electrode structure of claim 1 .

4. the first electrode is a sensor electrode that detects gripping of the steering wheel; The electrode structure of claim 1 .

5. a second electrode disposed on a second surface of the insulator opposite to the first surface; The electrode structure according to claim 2 .

6. In a cross section of the steering wheel taken along a plane perpendicular to the circumferential direction of the steering wheel, the first electrode is formed along the shape of the first surface of the insulator, the second electrode is formed along the shape of the second surface of the insulator. The electrode structure according to claim 5 .

7. the insulator includes a first insulator and a second insulator; the first insulator has the first surface and the second surface formed thereon; the first electrode is disposed on the first surface of the first insulator; the second electrode is disposed on the second surface of the first insulator, the second surface being the surface opposite to the first surface; The second insulator is disposed between the second electrode and the core; The engaging portion engages with the core metal. The electrode structure according to claim 5 .

8. the first insulator, the second insulator, the first electrode, and the second electrode are arranged in a range from at least an outer circumferential side of the steering wheel to an inner circumferential side of the steering wheel in a cross section of the steering wheel taken along a plane perpendicular to the circumferential direction of the steering wheel. The electrode structure according to claim 7 .

9. the first insulator is made of a resin material, the second insulator is made of a resin material, the first electrode includes a metal plating or a metal thin film; The second electrode includes a metal plating, a metal thin film, a metal sheet, or a metal plate. The electrode structure according to claim 7 .

10. the first insulator is made of a resin material, the second insulator is made of a resin material, the first electrode includes a resin sheet and a conductive wire; the conductive wire is disposed on a surface of the resin sheet opposite to the surface on the first surface side, and sewn with sewing thread; The second electrode includes a metal plating, a metal thin film, a metal sheet, or a metal plate. The electrode structure according to claim 7 .

11. the first insulator has a first positioning portion, the second insulator has a second positioning portion that engages with the first positioning portion; The electrode structure according to claim 7 .

12. An electrode structure disposed along the outer periphery of a core metal of a steering wheel provided in a vehicle, a first insulator; a resin sheet disposed on a first surface of the first insulator, the first surface being the surface opposite to the surface of the first insulator facing the core; a linear first electrode disposed on one surface of the resin sheet; a second electrode disposed on the other surface of the resin sheet, the other surface being the back surface of the one surface of the resin sheet, the second electrode being the surface on the first surface side; the first insulator has an engaging portion that engages with the core metal, The first electrode serves as both a sensor electrode for detecting gripping of the steering wheel and a heater wire for heating the steering wheel. Electrode structure.

13. The first electrode is used exclusively as the sensor electrode and as the heater wire. The electrode structure according to claim 2 .

14. When the first electrode is used as the sensor electrode, an AC voltage having the same phase as an AC voltage applied to the second electrode is applied to the first electrode. The electrode structure according to any one of claims 5 to 12.

15. The engaging portion is engaged with an engaged portion provided on the core metal. The electrode structure according to any one of claims 1 to 12.

16. The electrode structure according to any one of claims 1 to 12, The core metal; and a foam covering the core metal. Steering wheel.

17. The steering wheel according to claim 16, wherein the engaging portion of the electrode structure is engaged with an engaged portion provided on the core metal, the core metal is covered with the foam in a state where the engaging portion is engaged with the engaged portion; A method for manufacturing a steering wheel.

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