Steering wheel

Abstract

To provide a technique enabling coupling and electric connection between divided skin sensor layers by a simple method, in a steering wheel.SOLUTION: A steering wheel includes a gripping part gripped by a driver of a vehicle when the steering wheel is operated. The gripping part includes: a first skin sensor layer which includes a first end, a first skin layer arranged on an outermost layer of the gripping part, and a conductive first sensor layer to the first end that is provided on an inner layer side of the first skin layer; a second skin sensor layer which includes a second end, a second skin layer arranged on the outermost layer of the gripping part, and a conductive second sensor layer to the second end that is provided on an inner layer side of the second skin layer; and an electric connection part which connects at least the first end and the second end, and electrically connects the first sensor layer and the second sensor layer.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to steering wheels. [Background technology]

[0002] Steering wheels equipped with a sensor for detecting whether an occupant is in contact with the steering wheel are known. For example, Patent Document 1 discloses a steering wheel equipped with a skin material including a conductive elastic layer functioning as a sensor electrode and a coating layer laminated on the elastic layer. In this steering wheel, the skin material is divided into four regions, top, bottom, left and right, and covers the rim portion. The elastic layers of each divided skin material are electrically connected to each other by lead wires. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-202446 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the conventional technology, the rim is covered with a cover material connected with a lead wire, which may cause the lead wire to break and may make manufacturing difficult. Therefore, a technology is desired that makes it easy to electrically connect the conductive material of each divided cover material and to connect the divided cover materials to each other in a steering wheel. [Means for solving the problem]

[0005] The present disclosure can be realized in the following forms.

[0006] (1) According to one embodiment of the present disclosure, a steering wheel is provided. The steering wheel includes a gripping portion that is gripped by a driver of a vehicle when operating the steering wheel. The gripping portion includes a first end portion, a first skin layer disposed on the outermost layer of the gripping portion, a conductive first sensor layer disposed on the inner layer side of the first skin layer and reaching the first end portion, a second end portion, a second skin layer disposed on the outermost layer of the gripping portion, a conductive second sensor layer disposed on the inner layer side of the second skin layer and reaching the second end portion, and an electrical connection portion that connects at least the first end portion and the second end portion and electrically connects the first sensor layer and the second sensor layer. In this form of steering wheel, the electrical connection portion has the function of connecting the first epidermal sensor layer and the second epidermal sensor layer, and the function of electrically connecting the first sensor layer and the second sensor layer, so that the divided epidermal sensor layers can be connected and electrically connected in a simpler manner than when using lead wires. (2) In the steering wheel of the above aspect, the grip portion may further include a core layer including a core metal and having a groove on a surface thereof. The first end portion and the second end portion may be disposed in the groove with the surface of the first skin layer and the surface of the second skin layer overlapping each other. The electrical connection portion may connect the first end portion and the second end portion disposed in the groove. According to this form of steering wheel, the electrical connection portion, the first end portion, and the second end portion are disposed in the groove portion, thereby suppressing or preventing the connecting portion of the electrical connection portion, the first end portion, and the second end portion from being visible from outside the steering wheel. (3) In the steering wheel of the above-described embodiment, the grip portion may be divided into two or more regions including a first region in which the first epidermal sensor layer is arranged, and a second region adjacent to the first region in which the second epidermal sensor layer is arranged. According to the steering wheel of this embodiment, the skin sensor layer is divided into two or more regions, which makes it easy to attach the skin sensor layer to the core layer. (4) In the steering wheel of the above aspect, the electrical connection portion may be a conductive bonding material. The first sensor layer and the second sensor layer may be electrically connected by contact with the bonding material. The first end portion and the second end portion may be connected by bonding with the bonding material. According to the steering wheel of this type, the first and second skin sensor layers can be joined together and the first and second sensor layers can be electrically connected together by a simple method using a bonding material. (5) In the steering wheel of the above aspect, the electrical connection portion may include a conductive cloth including a conductive material and a fiber material, and a thread-like material. The first sensor layer and the second sensor layer may be electrically connected by contact with the conductive cloth. The first end portion and the second end portion may be connected by being sewn together with the conductive cloth by the thread-like material. With this type of steering wheel, the first epidermal sensor layer and the second epidermal sensor layer can be joined and the first sensor layer and the second sensor layer can be electrically connected by the simple method of sewing the conductive cloth. (6) In the steering wheel of the above aspect, the first sensor layer may include a first protruding portion protruding from the first skin layer at the first end. The electrical connection portion may include a thread-like material and the first protruding portion. The first sensor layer and the second sensor layer may be electrically connected by covering the second end with the first protruding portion in contact with the second sensor layer. The first end and the second end may be connected by being sewn together with the first protruding portion by the thread-like material. According to the steering wheel of this form, the first sensor layer and the second sensor layer can be electrically connected without using a conductive material separate from the first skin sensor layer and the second skin sensor layer. (7) In the steering wheel of the above aspect, the first sensor layer may include a first protruding portion protruding beyond the first skin layer at the first end. The second sensor layer may include a second protruding portion protruding beyond the second skin layer at the second end. The electrical connection portion may include a thread-like material, the first protruding portion, and the second protruding portion. The first sensor layer and the second sensor layer may be electrically connected by contact between the first protruding portion and the second protruding portion. The first end and the second end may be connected by sewing the first protruding portion and the second protruding portion together with the thread-like material. According to the steering wheel of this form, the first sensor layer and the second sensor layer can be electrically connected without using a conductive material separate from the first skin sensor layer and the second skin sensor layer. (8) In the steering wheel of the above aspect, the electrical connection portion may be a conductive thread. The first end portion and the second end portion may be connected by sewing the conductive thread. The first sensor layer and the second sensor layer may be electrically connected to each other via the conductive thread. With this form of steering wheel, the first epidermal sensor layer and the second epidermal sensor layer can be joined and the first sensor layer and the second sensor layer can be electrically connected by the simple method of sewing the first end and the second end. (9) In the steering wheel of the above-described form, the groove portion may include an outer circumferential groove portion formed on the outer periphery of the grip portion along the extension direction of the grip portion, and an inner circumferential groove portion formed on the inner periphery of the grip portion along the extension direction. According to the steering wheel of this type, different skin sensor layers can be provided on the front and back of the steering wheel. The present disclosure may be realized in various forms other than a steering wheel, for example, a vehicle equipped with a steering wheel, a steering device, a grip, a capacitance sensor, a method for manufacturing a steering wheel, a method for manufacturing a grip, a method for manufacturing a capacitance sensor, etc. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is an explanatory diagram showing the external configuration of a steering wheel according to a first embodiment. [Diagram 2] FIG. 2 is a cross-sectional view showing the position II-II in FIG. [Diagram 3] FIG. 4 is an explanatory diagram showing a schematic diagram of a method for attaching an epidermal sensor layer. [Figure 4] FIG. 4 is a cross-sectional view illustrating a state in which a first end of a first epidermal sensor layer and a second end of a second epidermal sensor layer are connected to each other. [Diagram 5] Cross-sectional view of the VV position in Figure 1. [Figure 6] FIG. 11 is an explanatory diagram showing the configuration of a grip portion of a steering wheel according to a second embodiment. [Figure 7] FIG. 11 is an explanatory diagram showing the configuration of a grip portion of a steering wheel according to a third embodiment. [Figure 8] FIG. 13 is an explanatory diagram showing the configuration of a grip portion of a steering wheel according to a fourth embodiment. [Figure 9] FIG. 13 is an explanatory diagram showing the configuration of a grip portion of a steering wheel according to a modified example of the fourth embodiment. [Figure 10] FIG. 13 is an explanatory diagram showing a cross-sectional view of a grip portion of a steering wheel according to a fifth embodiment. [Figure 11] FIG. 13 is an explanatory diagram showing the configuration of a grip portion of a steering wheel according to a modified example of the fifth embodiment. [Figure 12] FIG. 13 is an explanatory diagram showing the configuration of a grip portion of a steering wheel according to a sixth embodiment. [Figure 13] FIG. 13 is an explanatory diagram showing the configuration of a grip portion of a steering wheel according to a modified example of the sixth embodiment. [Figure 14] FIG. 13 is an explanatory diagram showing the configuration of a grip portion of a steering wheel according to a seventh embodiment. [Figure 15] FIG. 23 is an explanatory diagram showing the configuration of a grip portion of a steering wheel according to a modified example of the seventh embodiment. [Figure 16] FIG. 13 is an explanatory diagram showing the configuration of a grip portion of a steering wheel according to an eighth embodiment. [Figure 17] FIG. 23 is an explanatory diagram showing the configuration of a grip portion of a steering wheel according to a modified example of the eighth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] A. First embodiment: FIG. 1 is an explanatory diagram showing an external configuration of a steering wheel 100 according to a first embodiment of the present disclosure. The steering wheel 100 is provided, for example, at the driver's seat of a vehicle. The vehicle is, for example, an electric vehicle (BEV: Battery Electric Vehicle). The steering wheel 100 is a part of a steering device operated by a driver of the vehicle. The steering wheel 100 is connected to a steering shaft 10 and configured to be rotatable about an axis line AX of the steering shaft 10. The rotation of the steering wheel 100 is transmitted to a steering gear box (not shown) via the steering shaft 10.

[0009] FIG. 1 shows a steering wheel 100 on the rear side in the traveling direction of the vehicle. The direction along the axis AX of the steering shaft 10 is also called the "front-rear direction" in accordance with the traveling direction of the vehicle. In addition, when the orientation of the steering wheel 100 when viewed from the front when the vehicle is traveling straight is taken as a reference state, among the directions perpendicular to the axis AX, a direction parallel to the vertical direction of the steering wheel 100 in the reference state is also called the "up-down direction", and a direction perpendicular to the axis AX and perpendicular to the up-down direction is also called the "left-right direction". Note that FIG. 1 shows the steering wheel 100 in the reference state.

[0010] The steering wheel 100 includes a pad portion 20, a connecting portion 22, and a grip portion 24. The pad portion 20 is disposed at a position surrounded by the grip portion 24. A detection circuit 30 is provided in the pad portion 20. The connecting portion 22 is provided between the grip portion 24 and the pad portion 20, and connects the grip portion 24 and the pad portion 20. The grip portion 24 is a portion that is gripped by the driver when operating the steering wheel 100. In the example of FIG. 1, the grip portion 24 has a substantially annular shape centered on the axis AX of the steering shaft 10. However, the grip portion 24 is not limited to an annular shape, and may be any shape such as a polygonal shape or an elliptical shape, or may be an asymmetric shape such as a so-called D-shape. In addition, the grip portion 24 is not limited to an annular shape, and may be a plurality of grip portions that are not continuous with each other, such as a right grip portion and a left grip portion.

[0011] Fig. 2 is a cross-sectional view showing the position II-II in Fig. 1. Fig. 2 shows a schematic layered structure inside the gripping portion 24. The gripping portion 24 is formed by laminating a core layer 40 and an epidermal sensor layer 90 in this order from the inside. Note that in Fig. 2, each member of the gripping portion 24 is shown schematically to facilitate understanding of the technology, and the thickness of each member and the thickness ratio of each member are not shown accurately.

[0012] The core material layer 40 includes a metal core 42 and a coating layer 44. The metal core 42 is a conductive structure that functions as a skeleton of the steering wheel 100. The metal core 42 is made of, for example, iron, aluminum, magnesium, or an alloy thereof. The metal core 42 is also called a "core material." The coating layer 44 is an insulating structure disposed around the metal core 42. The coating layer 44 can be formed by in-mold molding using, for example, a soft material such as polyurethane foam or an elastic material. The coating layer 44 may be formed of a hard material.

[0013] As shown in FIG. 1, the surface of the core layer 40 is formed with grooves 40S1, 40S2, 40S3, and 40S4 that are concave relative to the surface of the core layer 40. The grooves 40S1, 40S2, 40S3, and 40S4 are formed in a direction intersecting the extension direction DC of the grip portion 24 in a front view. In the example of FIG. 1, the extension direction DC is substantially the same as the circumferential direction of the grip portion 24. That is, the grooves 40S1, 40S2, 40S3, and 40S4 are formed in a direction along the radial direction DR of the grip portion 24. In addition, in a cross-sectional view, the grooves 40S1, 40S2, 40S3, and 40S4 are formed around the entire circumference of the core layer 40 in the circumferential direction centered on the core metal 42. The grooves 40S1, 40S2, 40S3, and 40S4 are provided with electrical connection parts 70, as described later.

[0014] As shown in FIG. 2, the epidermal sensor layer 90 includes an epidermal layer 80 and a sensor layer 60. The epidermal layer 80 is the outermost layer of the grip portion 24 and is gripped by the driver. The epidermal layer 80 is top leather, split leather separated from the top leather, natural leather, artificial leather, synthetic leather, nonwoven fabric, rubber sheet, woven fabric, and the like. The natural leather is, for example, leather of mammals such as cows, birds, reptiles, and the like. The artificial leather is, for example, leather in which a nonwoven fabric is coated with a resin. The synthetic leather is, for example, leather in which a woven fabric or knitted fabric such as cloth or cotton is coated with a resin.

[0015] In this embodiment, the skin sensor layer 90 further includes an inner surface skin layer 82. The inner surface skin layer 82 is disposed on the inner surface side of the sensor layer 60. In this embodiment, the configuration of the inner surface skin layer 82 is similar to the configuration of the skin layer 80. However, the inner surface skin layer 82 may be made of a resin material, a rubber material, or the like. The inner surface skin layer 82 and the skin layer 80 may be made of the same material or different materials.

[0016] The sensor layer 60 is, for example, a conductive cloth in which a surface treatment such as a carbon coat or metal plating is applied to a fiber fabric. The sensor layer 60 may be a metal sheet or a metal fiber material. The sensor layer 60 generates a capacitance between the driver's hand in a state where the grip portion 24 is gripped. The sensor layer 60 is bonded to the inner surface side of the skin layer 80 using, for example, an adhesive or a double-sided adhesive tape. In the example of FIG. 2, the sensor layer 60 is on the inner layer side of the skin layer 80 and is provided between the skin layer 80 and the inner surface skin layer 82. "Provided between layers" means that the sensor layer 60 is provided at any position between each layer, and includes a state in which the sensor layer 60 is in contact with each layer and a state in which the sensor layer 60 is separated from each layer without contacting each layer by, for example, an adhesive or the like. When the grip portion 24 does not include the inner surface skin layer 82, the sensor layer 60 may be laminated on the core layer 40.

[0017] As shown in FIG. 1, the sensor layer 60 is electrically connected to the detection circuit 30 via the lead wire LR. The detection circuit 30 includes various circuits such as an oscillation circuit, a resonance circuit, a detection circuit, and an amplification circuit, and detects the gripping state of the grip portion 24 based on a change in capacitance generated in the sensor layer 60. Specifically, when the grip portion 24 is gripped by the driver, the capacitance between the sensor layer 60 as a detection electrode and the driver changes with respect to the capacitance when the grip portion 24 is not gripped. In the detection circuit 30, the resonance frequency changed with the change in capacitance is amplitude modulated. The original signal is extracted from the amplitude modulated signal, amplified, and output as a voltage. This voltage value is compared with a preset threshold value, and the comparison result is used to detect whether the grip portion 24 is being gripped. The detection result may be used, for example, for ON / OFF control of a heater grounded in the steering wheel 100, or for control of an airbag or the like. In addition, when it is detected that the hand has been released from the grip portion 24 while driving the vehicle, a buzzer or the like may be used to notify the driver or the like. The detection result may be displayed, for example, on a display unit (not shown) provided on the steering wheel 100 or in the vicinity thereof.

[0018] FIG. 3 is an explanatory diagram showing a schematic method of attaching the epidermal sensor layer 90. In FIG. 3, in order to facilitate understanding of the technique, illustration of members other than the epidermal sensor layer 90 and the core material layer 40 is omitted. As shown in FIG. 3, the epidermal sensor layer 90 is formed as one epidermal sensor layer 90 by connecting a plurality of divided epidermal sensor layers to each other. Specifically, the epidermal sensor layer 90 is formed by connecting four divided epidermal sensor layers, namely, a first epidermal sensor layer 90B, a second epidermal sensor layer 90R, a third epidermal sensor layer 90U, and a fourth epidermal sensor layer 90L, to each other. In FIG. 3, the first epidermal sensor layer 90B, the second epidermal sensor layer 90R, the third epidermal sensor layer 90U, and the fourth epidermal sensor layer 90L are in a state before being attached to the core material layer 40, and are in a state of being developed on a plane. In this specification, the epidermal sensor layer in a state in which they are connected is referred to as the "epidermal sensor layer 90".

[0019] 3 shows a plurality of regions AR1, AR2, AR3, and AR4 that divide the grip portion 24. The regions AR1, AR2, AR3, and AR4 indicate regions in which a plurality of divided epidermal sensor layers are arranged. The first epidermal sensor layer 90B is arranged in the region AR1, the second epidermal sensor layer 90R is arranged in the region AR2, the third epidermal sensor layer 90U is arranged in the region AR3, and the fourth epidermal sensor layer 90L is arranged in the region AR4. The region AR1 is also called the "first region AR1," the region AR2 is also called the "second region AR2," the region AR3 is also called the "third region AR3," and the region AR4 is also called the "fourth region AR4."

[0020] In the example of Fig. 3, the regions AR1, AR2, AR3, and AR4 are divided by the grooves 40S1, 40S2, 40S3, and 40S4 as boundaries. The positions of the regions AR1, AR2, AR3, and AR4 on the gripping portion 24 may be determined arbitrarily. In the example of Fig. 3, the region AR1 is a region below the axis line AX, the region AR2 is a region to the right of the axis line AX, the region AR3 is a region above the axis line AX, and the region AR4 is a region to the left of the axis line AX. Adjacent epidermal sensor layers are connected to each other using electrical connection parts 70. The epidermal sensor layers 90, which are connected and integrated, are wound around the core layer 40 to form the gripping portion 24.

[0021] As shown in FIG. 3, the first skin sensor layer 90B includes a first skin layer 80B, a first sensor layer 60B, and a first inner surface skin layer 82B. The first skin sensor layer 90B can be formed by stacking the first skin layer 80B, the first sensor layer 60B, and the first inner surface skin layer 82B, which are rectangular in shape and have a predetermined size in a plan view, one on top of the other, and then cutting the layer into a desired shape. Similarly, the second skin sensor layer 90R includes a second skin layer 80R, a second sensor layer 60R, and a second inner surface skin layer 82R. The third skin sensor layer 90U includes a third skin layer 80U, a third sensor layer 60U, and a third inner surface skin layer 82U. The fourth skin sensor layer 90L includes a fourth skin layer 80L, a fourth sensor layer 60L, and a fourth inner surface skin layer 82L. In this specification, the state in which the first sensor layer 60B, the second sensor layer 60R, the third sensor layer 60U, and the fourth sensor layer 60L are connected together is also referred to as the "sensor layer 60." Similarly, the state in which the first skin layer 80B, the second skin layer 80R, the third skin layer 80U, and the fourth skin layer 80L are connected together is also referred to as the "skin layer 80," and the state in which the first inner surface side skin layer 82B, the second inner surface side skin layer 82R, the third inner surface side skin layer 82U, and the fourth inner surface side skin layer 82L are connected together is also referred to as the "inner surface side skin layer 82."

[0022] In Fig. 3, the first epidermal sensor layer 90B, the second epidermal sensor layer 90R, the third epidermal sensor layer 90U, and the fourth epidermal sensor layer 90L are disposed at positions corresponding to the regions AR1, AR2, AR3, and AR4, respectively. In this state, when one end of the first epidermal sensor layer 90B along the stretching direction DC of the gripping portion 24 is defined as the first end E1 and one end of the second epidermal sensor layer 90R along the stretching direction DC is defined as the second end E2, the first end E1 is connected to the second end E2 using the electrical connection portion 70 and disposed in the groove portion 40S1. Similarly, when one end of the third epidermal sensor layer 90U along the stretching direction DC is defined as the third end E3 and one end of the fourth epidermal sensor layer 90L along the stretching direction DC is defined as the fourth end E4, the third end E3 is connected to the fourth end E4 using the electrical connection portion 70 and disposed in the groove portion 40S3.

[0023] When the other end of the first epidermal sensor layer 90B along the stretching direction DC is the first other end E12 and the other end of the fourth epidermal sensor layer 90L is the fourth other end E42, the first other end E12 is connected to the fourth other end E42 using the electrical connection part 70 and is disposed in the groove 40S4. Similarly, when the other end of the second epidermal sensor layer 90R along the stretching direction DC is the second other end E22 and the other end of the third epidermal sensor layer 90U is the third other end E32, the second other end E22 is connected to the third other end E32 using the electrical connection part 70 and is disposed in the groove 40S2.

[0024] FIG. 4 is an explanatory diagram showing a cross-sectional view of a state in which the first end E1 of the first epidermal sensor layer 90B and the second end E2 of the second epidermal sensor layer 90R are connected. FIG. 4 shows a cross-sectional view of the VV position in FIG. 1. As shown in FIG. 4, the first epidermal sensor layer 90B and the second epidermal sensor layer 90R are bent toward the gripping portion 24 at the first end E1 and the second end E2. The surface of the first epidermal layer 80B and the surface of the second epidermal layer 80R are overlapped with each other, and the first end E1 and the second end E2 are overlapped with each other and bound. The first end E1 and the second end E2 in the bound state are connected to the second end E2 by using the electrical connection portion 70 at a position corresponding to the groove portion 40S1. As shown in FIG. 4, the first end E1 and the second end E2 may be sewn using a thread-like material 88 using general natural fibers or chemical fibers in addition to the electrical connection portion 70. Stitching facilitates the application of the electrical connection portion 70 to the first end E1 and the second end E2, and the insertion of the first end E1 and the second end E2 into the groove portion 40S1.

[0025] In this embodiment, the electrical connection portion 70 is a bonding material having electrical conductivity. Specifically, the electrical connection portion 70 is a liquid conductive adhesive containing a conductive filler as a conductive material. The electrical connection portion 70 is mainly composed of an elastomer material, a rubber material, or polyvinyl chloride. For example, acrylic, styrene, silicon, olefin, urethane, and epoxy materials can be used as the elastomer material. For the rubber material, butadiene rubber, silicon rubber, and ethylene propylene diene rubber can be used. The electrical connection portion 70 may be a material in which a resin material or a rubber material is dissolved in a solvent such as an organic solvent or in water, or may be a thermosetting or photosetting material. The electrical connection portion 70 may be an adhesive instead of an adhesive. That is, the joining by the electrical connection portion 70 may be performed by adhesion or by bonding.

[0026] As the conductive filler contained in the electrical connection portion 70, various conductive fillers such as metal-based, carbon-based, metal oxide-based, and metal plating-based conductive fillers, such as silver, copper, gold, platinum, palladium, iron, aluminum, nickel, or carbon, can be used. The conductive filler can be in various shapes, such as powder or fiber.

[0027] 5 is a cross-sectional view taken along the VV position in FIG. 1. FIG. 5 shows a cross-sectional view of the groove 40S1 in which the connecting portion between the first end E1 and the second end E2 is disposed. As shown in FIG. 4, the first end E1 and the second end E2 covered by the electrical connection portion 70 are inserted into the groove 40S1. As shown in FIG. 5, the first end E1 and the second end E2 are connected to each other by the connection of the electrical connection portion 70, and are joined to the groove 40S1 by the electrical connection portion 70. The configurations of the grooves 40S2, 40S3, and 40S4 other than the groove 40S1 are the same as those of the groove 40S1, and will be described below using the example of the groove 40S1.

[0028] The first sensor layer 60B of the first epidermal sensor layer 90B contacts the electrical connection portion 70 at a first end E1, and the second sensor layer 60R of the second epidermal sensor layer 90R contacts the electrical connection portion 70 at a second end E2. As a result, the first sensor layer 60B and the second sensor layer 60R are electrically connected to each other via the electrical connection portion 70.

[0029] Similarly, the first sensor layer 60B is electrically connected to the fourth sensor layer 60L of the fourth epidermal sensor layer 90L by the electrical connection portion 70 provided in the groove portion 40S4. The third epidermal sensor layer 90U is electrically connected to the second epidermal sensor layer 90R at the position of the groove portion 40S2, and is electrically connected to the fourth epidermal sensor layer 90L at the position of the groove portion 40S3. The third sensor layer 60U of the third epidermal sensor layer 90U is electrically connected to the second sensor layer 60R of the second epidermal sensor layer 90R by the electrical connection portion 70 provided in the groove portion 40S2, and is electrically connected to the fourth sensor layer 60L of the fourth epidermal sensor layer 90L by the electrical connection portion 70 provided in the groove portion 40S3. As a result, as shown in FIG. 1, the first sensor layer 60B, the second sensor layer 60R, the third sensor layer 60U, and the fourth sensor layer 60L are formed as one sensor layer 60 that functions as a capacitance sensor.

[0030] As described above, according to the steering wheel 100 of this embodiment, the grip portion 24 includes the first epidermal sensor layer 90B having the conductive first sensor layer 60B extending to the first end E1, the second epidermal sensor layer 90R having the conductive second sensor layer 60R extending to the second end E2, and the electrical connection portion 70 that connects the first end E1 and the second end E2 and electrically connects the first sensor layer 60B and the second sensor layer 60R. Since the electrical connection portion 70 has a function of connecting the first epidermal sensor layer 90B and the second epidermal sensor layer 90R and a function of electrically connecting the first sensor layer 60B and the second sensor layer 60R, the divided epidermal sensor layers can be connected and electrically connected in a simpler manner than when using lead wires. In addition, the contact area between the electrical connection portion 70 and the first sensor layer 60B and the second sensor layer 60R can be made larger than when using lead wires, and the possibility of short-circuiting between the first sensor layer 60B and the second sensor layer 60R can be suppressed.

[0031] According to the steering wheel 100 of this embodiment, the first end E1 and the second end E2 are arranged in the groove 40S1 with the surface of the first skin layer 80B and the surface of the second skin layer 80R overlapping each other. The electrical connection portion 70 connects the first end E1 and the second end E2 arranged in the groove 40S1. By arranging the electrical connection portion 70, the first end E1, and the second end E2 in the groove 40S1, it is possible to suppress or prevent the electrical connection portion 70 and the first end E1 and the second end E2 in the connected state from being viewed from the outside of the steering wheel 100. Therefore, it is possible to improve the design of the steering wheel 100. In addition, it is possible to prevent the conductive electrical connection portion 70 from being exposed on the surface of the grip portion 24. By utilizing the groove 40S1, it is easier to fix the first end E1 and the second end E2 to the core material layer 40 compared to the case where the first end E1 and the second end E2 are arranged on the surface of the core material layer 40.

[0032] According to the steering wheel 100 of this embodiment, the grip portion 24 is divided into two or more regions including a first region AR1 in which the first skin sensor layer 90B is disposed, and a second region AR2 adjacent to the first region AR1 in which the second skin sensor layer 90R is disposed. By dividing the skin sensor layer 90 into two or more regions, it becomes easier to attach the skin sensor layer 90 to the core layer 40, and the productivity of the steering wheel 100 can be improved. In addition, for example, it becomes easier to switch between the presence and absence of the sensor layer 60 for each divided region, and to switch the color of the skin layer 80 for each divided region, and the like, and this improves the design freedom of the steering wheel 100 with respect to design and grip detection function.

[0033] According to the steering wheel 100 of this embodiment, the electrical connection portion 70 is a bonding material having electrical conductivity. The first sensor layer 60B and the second sensor layer 60R are electrically connected by contact with the bonding material, and the first end E1 and the second end E2 are connected by bonding with the bonding material. By a simple method of bonding with a bonding material, it is possible to realize the connection between the first epidermis sensor layer 90B and the second epidermis sensor layer 90R and the electrical connection between the first sensor layer 60B and the second sensor layer 60R. In addition, the epidermis sensor layer 90 can be bonded to the core material layer 40 by applying the electrical connection portion 70 to the contact surface of the epidermis sensor layer 90 with the core material layer 40.

[0034] B. Second embodiment: FIG. 6 is an explanatory diagram showing a cross-sectional view of the configuration of the grip portion 24 of the steering wheel 100 according to the second embodiment. The steering wheel 100 of this embodiment includes a first skin sensor layer 90Bb and a second skin sensor layer 90Rb instead of the first skin sensor layer 90B and the second skin sensor layer 90R. In the above-mentioned first embodiment, the first skin sensor layer 90B includes the first inner surface skin layer 82B, and the second skin sensor layer 90R includes the second inner surface skin layer 82R. In contrast, this embodiment differs from the first embodiment in that the first skin sensor layer 90Bb does not include the first inner surface skin layer 82B, and the second skin sensor layer 90Rb does not include the second inner surface skin layer 82R. The other configurations are the same as those of the first embodiment. It is not limited to the case where both the first inner surface side skin layer 82B of the first skin sensor layer 90Bb and the second inner surface side skin layer 82R of the second skin sensor layer 90Rb are omitted, and at least one of them may be omitted.

[0035] The steering wheel 100 configured in this manner can also provide the same effects as those of the first embodiment. In addition, the contact area between the first sensor layer 60B and the electrical connection portion 70 and the contact area between the second sensor layer 60R and the electrical connection portion 70 can be made larger than when the inner surface skin layer 82 is provided, making it easier to electrically connect the first sensor layer 60B and the second sensor layer 60R via the electrical connection portion 70. In addition, the possibility of a short circuit between the first sensor layer 60B and the second sensor layer 60R can be further reduced.

[0036] C. Third embodiment: Fig. 7 is an explanatory diagram showing a cross-sectional view of the configuration of the grip portion 24 of a steering wheel 100 according to a third embodiment. As shown in Fig. 7, the steering wheel 100 of the third embodiment is different from the first embodiment in that it includes a core material layer 40c that does not include the grooves 40S1, 40S2, 40S3, and 40S4 instead of the core material layer 40, and in that it includes a first epidermal sensor layer 90Bc and a second epidermal sensor layer 90Rc instead of the first epidermal sensor layer 90B and the second epidermal sensor layer 90R. The other configurations are the same as those of the first embodiment.

[0037] In the first embodiment, the first end E1 and the second end E2 are joined to each other by the electrical connection portion 70 and disposed in the groove portion 40S1. In contrast, as shown in Fig. 7, the connection between the first epidermal sensor layer 90B and the second epidermal sensor layer 90R by the electrical connection portion 70 and the electrical connection between the first sensor layer 60B and the second sensor layer 60R may be performed at a position other than the groove portions 40S1, 40S2, 40S3, and 40S4, such as the surface of the core layer 40. According to the steering wheel 100 configured in this manner, it is possible to obtain the same effect as the first embodiment without providing the groove portions 40S1, 40S2, 40S3, and 40S4.

[0038] In this embodiment, the first skin sensor layer 90Bc differs from the first skin sensor layer 90B in that the first skin layer 80Bc protrudes toward the second skin sensor layer 90Rc side from the first inner surface skin layer 82B and the first sensor layer 60B. The second skin sensor layer 90Rc differs from the second skin sensor layer 90R in that the second skin layer 80Rc protrudes toward the first skin sensor layer 90Bc side from the second inner surface skin layer 82R and the second sensor layer 60R. By connecting the first end E1 and the second end E2 in a state in which the first skin layer 80B protrudes beyond the first sensor layer 60B and the second skin layer 80R protrudes beyond the second sensor layer 60R, it is possible to suppress or prevent the electrical connection portion 70 from being exposed on the surface of the grip portion 24.

[0039] D. Fourth embodiment: Fig. 8 is an explanatory diagram showing the configuration of the grip portion 24 of the steering wheel 100 according to the fourth embodiment. Note that Fig. 8 and Figs. 9 to 11, which will be described later, show a state before the epidermal sensor layer 90 is attached to the core material layer 40.

[0040] In this embodiment, the gripping portion 24 is different from the first embodiment in that it includes an electrical connection portion 70d instead of the electrical connection portion 70, and other configurations are the same as those of the first embodiment. In the first embodiment, an example was shown in which the electrical connection portion 70 is a liquid conductive adhesive. In contrast, in this embodiment, the electrical connection portion 70d is different in that it includes a conductive cloth 76 in which a surface treatment such as metal plating has been applied to a fiber cloth, and a thread-like material 78 made of general natural fibers or chemical fibers. Note that a conductive thread may be used instead of the thread-like material 78. The conductive cloth 76 may be made of the same material as the sensor layer 60.

[0041] The conductive cloth 76 is disposed so as to cover the first end E1 and the second end E2. The first sensor layer 60B and the second sensor layer 60R are in contact with the conductive cloth 76 and are electrically connected to each other via the conductive cloth 76. The first end E1 and the second end E2 are connected together with the conductive cloth 76 by sewing them together with the thread-like material 78 in this state.

[0042] The steering wheel 100 configured in this manner can also provide the same effects as those of the first embodiment. The first epidermal sensor layer 90B and the second epidermal sensor layer 90R can be joined together and the first sensor layer 60B and the second sensor layer 60R can be electrically connected together by a simple method of sewing the conductive cloth 76. Furthermore, when the conductive cloth 76 made of the same material as the sensor layer 60 is used for the electrical connection portion 70d, the process of preparing a dedicated material for the electrical connection portion 70d can be omitted, improving productivity.

[0043] FIG. 9 is an explanatory diagram showing the configuration of the grip portion 24 of the steering wheel 100 according to a modification of the fourth embodiment. As shown in FIG. 9, the first epidermal sensor layer 90Bb and the second epidermal sensor layer 90R shown in the second embodiment may be used instead of the first epidermal sensor layer 90Bb and the second epidermal sensor layer 90Rb. Even in this case, the same effect as in the fourth embodiment can be obtained. In addition, by increasing the contact area between the first sensor layer 60B and the second sensor layer 60R and the conductive cloth 76, the electrical connection between the first sensor layer 60B and the second sensor layer 60R by the electrical connection portion 70d becomes easier.

[0044] E. Fifth embodiment: 10 is an explanatory diagram showing a cross-sectional view of the configuration of the grip portion 24 of a steering wheel 100 according to a fifth embodiment. This embodiment differs from the first embodiment in that an electrical connection portion 70e is provided instead of the electrical connection portion 70, but the other configurations are the same as those of the first embodiment.

[0045] In the first embodiment, the electrical connection portion 70 is a liquid conductive adhesive, but in this embodiment, the electrical connection portion 70e is made of a conductive double-sided adhesive tape. The steering wheel 100 configured in this manner can also achieve the same effects as the first embodiment. In addition, the use of double-sided adhesive tape makes it easier to apply the adhesive to the first end E1 and the second end E2, and to insert the first end E1 and the second end E2 in a joined state into the groove portion 40S1.

[0046] FIG. 11 is an explanatory diagram showing the configuration of the grip portion 24 of the steering wheel 100 according to a modified example of the fifth embodiment. As shown in FIG. 11, the first skin sensor layer 90Bb and the second skin sensor layer 90Rb shown in the second embodiment may be used instead of the first skin sensor layer 90B and the second skin sensor layer 90R. Even in this case, the same effect as in the fifth embodiment can be obtained. In addition, by increasing the contact area between the first sensor layer 60B and the second sensor layer 60R and the electrical connection portion 70e, the electrical connection between the first sensor layer 60B and the second sensor layer 60R by the electrical connection portion 70e is made easier. In the example of FIG. 10 and FIG. 11, the thread-like material 88 is omitted, but the first end E1 and the second end E2 may be sewn together by the thread-like material 88 as in the first embodiment.

[0047] F. Sixth embodiment: 12 is an explanatory diagram showing the configuration of the grip portion 24 of a steering wheel 100 according to a sixth embodiment. This embodiment differs from the first embodiment in that the grip portion 24 includes a first epidermal sensor layer 90Bf instead of the first epidermal sensor layer 90B and an electrical connection portion 70f instead of the electrical connection portion 70. Other configurations are the same as those of the first embodiment.

[0048] The first epidermal sensor layer 90Bf differs from the first epidermal sensor layer 90B in that the first epidermal sensor layer 90Bf includes a first sensor layer 60Bf instead of the first sensor layer 60B. The first sensor layer 60Bf includes a first protruding portion 60BE that protrudes from the first epidermal layer 80B at the first end E1. As shown in FIG. 12, the first protruding portion 60BE is bent so as to cover the second end E2. The second sensor layer 60R contacts the first protruding portion 60BE that covers the second end E2, and thus the first sensor layer 60B and the second sensor layer 60R are electrically connected to each other via the first protruding portion 60BE.

[0049] The electrical connection portion 70f includes a thread-like material 78 and a first protruding portion 60BE. The thread-like material 78 may be conductive or non-conductive. As shown in FIG. 12, the first end E1 and the second end E2 are connected to each other by being sewn together with the first protruding portion 60BE covering the second end E2 by the thread-like material 78. In addition, a bonding material for bonding the first end E1 and the second end E2 to the groove portion 40S1 may be provided in the groove portion 40S1. When the first sensor layer 60B and the second sensor layer 60R can be kept electrically connected to each other by the bonding material, the thread-like material 78 can be omitted.

[0050] The steering wheel 100 configured in this manner can also provide the same effects as those of the first embodiment. Furthermore, according to the steering wheel 100 of this embodiment, the first sensor layer 60B and the second sensor layer 60R can be electrically connected without using a conductive material separate from the first skin sensor layer 90B and the second skin sensor layer 90R. This allows the number of parts of the steering wheel 100 to be reduced.

[0051] FIG. 13 is an explanatory diagram showing the configuration of the grip portion 24 of the steering wheel 100 according to a modified example of the sixth embodiment. As shown in FIG. 13, as in the second embodiment, at least one of the first inner surface side skin layer 82B of the first skin sensor layer 90Bf and the second inner surface side skin layer 82R of the second skin sensor layer 90R may be omitted. Even in this case, the same effect as in the sixth embodiment can be obtained. In addition, by increasing the contact area between the first protrusion 60BE and the second sensor layer 60R, the electrical connection between the first sensor layer 60B and the second sensor layer 60R by the electrical connection portion 70f is made easier.

[0052] G. Seventh embodiment: 14 is an explanatory diagram showing the configuration of the grip portion 24 of the steering wheel 100 according to the seventh embodiment. This embodiment differs from the first embodiment in that the grip portion 24 includes a first epidermal sensor layer 90Bg instead of the first epidermal sensor layer 90B, a second epidermal sensor layer 90Rg instead of the second epidermal sensor layer 90R, and an electrical connection portion 70g instead of the electrical connection portion 70, but the other configurations are the same as those of the first embodiment.

[0053] The first epidermal sensor layer 90Bg is different from the first epidermal sensor layer 90B in that the first sensor layer 60Bg is provided instead of the first sensor layer 60B. The first sensor layer 60Bg is provided with a first protruding portion 60BE that protrudes from the first epidermal layer 80B at the first end E1. The second epidermal sensor layer 90Rg is different from the second epidermal sensor layer 90R in that the second sensor layer 60Rg is provided instead of the second sensor layer 60R. The second sensor layer 60Rg is provided with a second protruding portion 60RE that protrudes from the second epidermal layer 80R at the second end E2. As shown in FIG. 14, the first protruding portion 60BE and the second protruding portion 60RE are in contact with each other, and thus the first sensor layer 60Bg and the second sensor layer 60Rg are electrically connected to each other.

[0054] The electrical connection portion 70g includes a thread-shaped material 78, a first protruding portion 60BE, and a second protruding portion 60RE. The thread-shaped material 78 may be conductive or non-conductive. As shown in FIG. 14, the thread-shaped material 78 sews the first sensor layer 60Bg and the second sensor layer 60Rg in contact with each other, thereby connecting the first end E1 and the second end E2 to each other. In addition, a bonding material for bonding the first end E1 and the second end E2 to the groove portion 40S1 may be provided in the groove portion 40S1. If the bonding material can maintain the first sensor layer 60Bg and the second sensor layer 60Rg in an electrically connected state, the thread-shaped material 78 can be omitted. The bonding material may be conductive or non-conductive.

[0055] The steering wheel 100 configured in this manner can also provide the same effects as those of the first embodiment. Furthermore, according to the steering wheel 100 of this embodiment, the first sensor layer 60B and the second sensor layer 60R can be electrically connected without using a conductive material separate from the first skin sensor layer 90Bg and the second skin sensor layer 90Rg. This allows the number of parts of the steering wheel 100 to be reduced.

[0056] 15 is an explanatory diagram showing the configuration of the grip portion 24 of a steering wheel 100 according to a modified example of the seventh embodiment. As in the second embodiment, at least one of the first inner surface skin layer 82B of the first skin sensor layer 90Bg and the second inner surface skin layer 82R of the second skin sensor layer 90Rg may be omitted. Even in this case, the same effects as those of the seventh embodiment can be obtained.

[0057] H. Eighth embodiment: FIG. 16 is an explanatory diagram showing the configuration of the grip portion 24 of the steering wheel 100 according to the eighth embodiment. This embodiment differs from the first embodiment in that the grip portion 24 includes an electrical connection portion 70h instead of the electrical connection portion 70, and the other configurations are the same as those of the first embodiment. The electrical connection portion 70h is a conductive thread. The conductive thread means a conductive thread-like material in which a fiber material such as a chemical fiber is coated with a conductive material such as a metal or carbon by plating or coating. The conductive thread may be formed of a metal fiber in which a metal such as stainless steel is fiberized.

[0058] 16, the first end E1 and the second end E2 in the bound state are sewn and connected to each other by an electrical connection part 70h as a conductive thread, as in the first embodiment. The first sensor layer 60B and the second sensor layer 60R are in contact with the conductive thread that passes through the first end E1 and the second end E2, and are electrically connected to each other via the conductive thread.

[0059] The steering wheel 100 of this embodiment can also provide the same effects as those of the first embodiment. According to the steering wheel 100 of this embodiment, the first sensor layer 60B and the second sensor layer 60R are electrically connected to each other via a conductive thread. Therefore, by a simple method of sewing the first end E1 and the second end E2, the first epidermal sensor layer 90B and the second epidermal sensor layer 90R can be joined and the first sensor layer 60B and the second sensor layer 60R can be electrically connected to each other.

[0060] Fig. 17 is an explanatory diagram showing the configuration of the grip portion 24 of a steering wheel 100 according to a modified example of the eighth embodiment. As shown in Fig. 17, the first epidermal sensor layer 90Bb and the second epidermal sensor layer 90Rb shown in the second embodiment may be used instead of the first epidermal sensor layer 90B and the second epidermal sensor layer 90R. Even in this case, the same effects as those of the eighth embodiment can be obtained.

[0061] I. Other embodiments: (I1) In each of the above embodiments, an example has been shown in which the vehicle equipped with the steering wheel 100 is an electric vehicle. However, the vehicle is not limited to an electric vehicle, and may be, for example, a gasoline-powered vehicle, a hybrid vehicle, or a fuel cell vehicle. The vehicle may be a passenger car, a truck, a bus, a construction vehicle, or the like, and may include various types of automobiles such as two-wheeled vehicles and four-wheeled vehicles, as well as trains.

[0062] (I2) In the above-mentioned first embodiment, an example was shown in which the grip portion 24 is divided into four regions AR1, AR2, AR3, and AR4, which are divided into four regions, ie, upper, lower, left, and right, with the grooves 40S1, 40S2, 40S3, and 40S4 as boundaries. In contrast, the regions are not limited to being divided into the boundaries of the grooves, and may be divided into any position of the grip portion 24 as a boundary. In addition, each region may be divided into any size, shape, range, etc. The number of regions is not limited to four, upper, lower, left, and right, and may be divided into any number of regions equal to or greater than two, such as two regions on the left and right, two regions on the top and bottom, six regions, or eight regions. In this case, the epidermal sensor layer 90 includes at least the first epidermal sensor layer 90B and the second epidermal sensor layer 90R, and is divided into any number of regions equal to or greater than two, which corresponds to the number of divided regions.

[0063] (I3) In the above embodiment, an example was shown in which the gripping portion 24 includes the core layer 40 and the epidermal sensor layer 90. However, the gripping portion 24 may further include another member, such as a heater layer, between the epidermal sensor layer 90 and the core layer 40. The heater layer is formed, for example, from a flexible sheet material in which a heating element is disposed in a resin material, and generates heat when electricity is applied, thereby raising the temperature of the gripping portion 24.

[0064] (I4) In the above first embodiment, an example was shown in which the grooves 40S1, 40S2, 40S3, and 40S4 are formed in a direction along the radial direction DR of the grip portion 24. In contrast, the grooves may be formed along the extension direction DC of the grip portion 24. In this case, the groove may be one groove formed around the entire circumference of the core material layer 40, or multiple grooves. In addition, the grooves may include an outer circumferential groove portion formed on the outer periphery of the grip portion 24 along the extension direction DC of the grip portion 24, and an inner circumferential groove portion formed on the inner periphery of the grip portion 24 along the extension direction DC.

[0065] According to the steering wheel 100 configured in this manner, different skin sensor layers 90 can be provided at the front and rear of the steering wheel 100, i.e., on the front and back of the steering wheel 100. This makes it easy to switch between the presence and absence of the sensor layer 60 in the front-rear direction and to switch the color of the skin layer 80 in the front-rear direction, thereby improving the design freedom of the steering wheel 100 with respect to design and grip detection function.

[0066] The present disclosure is not limited to the above-mentioned embodiment, and can be realized in various configurations without departing from the spirit of the present disclosure. For example, the technical features in the embodiments corresponding to the technical features in each aspect described in the Summary of the Invention column can be appropriately replaced or combined to solve some or all of the above-mentioned problems or to achieve some or all of the above-mentioned effects. Furthermore, if the technical feature is not described as essential in this specification, it can be appropriately deleted. [Explanation of symbols]

[0067] 10... steering shaft, 20... pad portion, 22... connecting portion, 24... grip portion, 30... detection circuit, 40, 40c... core material layer, 40S1, 40S2, 40S3, 40S4... groove portion, 42... core metal, 44... coating layer, 60... sensor layer, 60B, 60Bf, 60Bg... first sensor layer, 60BE... first protruding portion, 60L... fourth sensor layer, 60R, 60Rg...second sensor layer, 60RE...second protrusion, 60U...third sensor layer, 70, 70d, 70e, 70f, 70g, 70h...electrical connection portion, 76...conductive cloth, 78...filamentous material, 80...skin layer, 80B, 80Bc...first skin layer, 80L...fourth skin layer, 80R, 80Rc...second skin layer, 80U...third skin layer, 82...inner skin layer, 82B...first inner surface skin layer, 82L...fourth inner surface skin layer, 82R...second inner surface skin layer, 82U...third inner surface skin layer, 88...thread-like material, 90...skin sensor layer, 90B, 90Bb, 90Bc, 90Bf, 90Bg...first skin sensor layer, 90L...fourth skin sensor layer, 90R, 90Rb, 90Rc, 90Rg...second skin sensor layer, 90U...third skin sensor layer, 100...steering wheel, AR1...first region, AR2...second region, AR3...third region, AR4...fourth region, AX...axis, E1...first end, E12...first other end, E2...second end, E22...second other end, E3...third end, E32...third other end, E4...fourth end, E42...fourth other end, LR...lead wire

Claims

1. A steering wheel, a gripping portion that is gripped by a driver of the vehicle when operating the steering wheel, The gripping portion is a first skin sensor layer including a first end portion, a first skin layer disposed on the outermost layer of the grip portion, and a conductive first sensor layer disposed on an inner layer side of the first skin layer and reaching the first end portion; a second skin sensor layer including a second end portion, a second skin layer disposed on the outermost layer of the grip portion, and a conductive second sensor layer disposed on an inner layer side of the second skin layer and reaching the second end portion; an electrical connection portion that connects at least the first end portion and the second end portion and electrically connects the first sensor layer and the second sensor layer; Steering wheel.

2. 2. A steering wheel according to claim 1, The gripping portion further includes a core layer including a core metal and having a groove on a surface thereof, the first end and the second end are disposed in the groove with the surface of the first skin layer and the surface of the second skin layer overlapping each other; the electrical connection portion connects the first end and the second end disposed in the groove; Steering wheel.

3. 2. A steering wheel according to claim 1, the gripping portion is divided into two or more regions including a first region in which the first epidermal sensor layer is disposed, and a second region adjacent to the first region in which the second epidermal sensor layer is disposed; Steering wheel.

4. 2. A steering wheel according to claim 1, the electrical connection portion is a bonding material having electrical conductivity; the first sensor layer and the second sensor layer are electrically connected by contact with the bonding material; the first end and the second end are connected by a bond of the bonding material; Steering wheel.

5. 2. A steering wheel according to claim 1, The electrical connection portion includes a conductive cloth including a conductive material and a fiber material, and a thread-like material; the first sensor layer and the second sensor layer are electrically connected by contact with the conductive cloth; the first end and the second end are connected to each other by being sewn together with the conductive cloth by the thread-like material; Steering wheel.

6. 2. A steering wheel according to claim 1, the first sensor layer includes a first protruding portion protruding beyond the first skin layer at the first end portion; the electrical connection portion includes a thread-like material and the first protrusion; the first sensor layer and the second sensor layer are electrically connected by the first protrusion covering the second end with the first protrusion in contact with the second sensor layer; the first end and the second end are connected by being stitched together with the first protrusion by the thread-like material; Steering wheel.

7. 2. A steering wheel according to claim 1, the first sensor layer includes a first protruding portion protruding beyond the first skin layer at the first end portion; the second sensor layer includes a second protruding portion protruding beyond the second skin layer at the second end, the electrical connection portion includes a thread-like material, the first protrusion, and the second protrusion; the first sensor layer and the second sensor layer are electrically connected by contact between the first protruding portion and the second protruding portion; the first end and the second end are connected by stitching the first protrusion and the second protrusion with the thread-like material; Steering wheel.

8. 2. A steering wheel according to claim 1, the electrical connection is a conductive thread; the first end and the second end are connected by stitching the conductive thread; the first sensor layer and the second sensor layer are electrically connected to each other via the conductive thread; Steering wheel.

9. 3. A steering wheel according to claim 2, The groove portion includes an outer circumferential groove portion formed on an outer circumferential surface of the grip portion along an extension direction of the grip portion, and an inner circumferential groove portion formed on an inner circumferential surface of the grip portion along the extension direction. Steering wheel.

Images