Sensor device and steering wheel

Abstract

The problem is solved by a capacitive sensor device built in a steering wheel, the sensor device being characterized in that the steering wheel has a rim and a spoke connected to the inside of the rim, the sensor device comprising an electrode capable of capacitively coupling with an object to be detected, and a control unit, the sensor device is provided on the spoke, and the control unit detects a change in capacitance of the electrode generated when an object comes into contact with or approaches the rim or the spoke, and determines whether or not the object comes into contact with or approaches the spoke on the basis of the change in capacitance.

Description

[0001] This application is a divisional application of the invention patent application with Chinese patent application number 202080014348.X and invention name “Sensor device and steering wheel” filed by the present applicant on March 3, 2020. Technical Field

[0002] The invention relates to a sensor device and a steering wheel. Background Art

[0003] When driving a car or other vehicle, a person holds a steering wheel and operates the steering wheel. By rotating the steering wheel, the direction of travel of the vehicle can be changed. The steering wheel is also called a steering wheel.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2015-147531 Summary of the invention

[0007] Technical problem to be solved by the invention

[0008] However, some steering wheels have a built-in sensor device for detecting whether a person is holding the steering wheel. Specifically, some steering wheels have a detection electrode (e.g., an electrostatic capacitive sensor) provided on the rim of the steering wheel for detecting whether the driver is holding the rim of the steering wheel when driving the vehicle. On the other hand, it is considered that the rim of the steering wheel has a heater inside to avoid the feeling of coldness when a person's hands touch or approach it. If a heater is provided inside the rim of such a steering wheel, there will be a problem that the detection accuracy of the sensor device is reduced due to interference mainly caused by changes in the detection sensitivity due to changes in the electromagnetic field or temperature formed around the heater.

[0009] Therefore, a sensor device capable of detecting the contact or approach of a human hand with high accuracy is required in the steering wheel.

[0010] Means for solving technical problems

[0011] According to one viewpoint of the present embodiment, a sensor device is provided for detecting the contact or approach of a driver's hand to a steering wheel, characterized in that the steering wheel has a rim and spokes connected to the inner side of the rim, and the sensor device comprises: electrodes, arranged on the spokes of the steering wheel, capable of capacitive coupling with the driver's hand to be detected; and a control unit, detecting changes in the electrostatic capacitance of the electrode generated when the driver's hand contacts or approaches the rim, and whether the driver's hand contacts or approaches the rim is judged based on the changes in the electrostatic capacitance.

[0012] According to one viewpoint of the present embodiment, there is a capacitive sensor device built into a steering wheel, characterized in that the steering wheel has a rim and spokes connected to the inner side of the rim, and the sensor device includes: an electrode capable of capacitive coupling with an object to be detected; and a control unit, wherein the sensor device is arranged on the spoke, and the control unit detects changes in the electrostatic capacitance of the electrode generated when an object is in contact with or close to the rim or the spoke, and determines whether the object is in contact with or close to the rim or the spoke based on the changes in the electrostatic capacitance.

[0013] Effects of the Invention

[0014] According to the disclosed sensor device, even if it is impossible to install an electrostatic capacitance sensor on the rim of the steering wheel, it is possible to detect with high accuracy that a human hand is in contact with or close to the rim and the spokes. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is an illustration of a conventional steering wheel.

[0016] Figure 2 This is a cross-sectional view of a structure in which a heater is provided around a capacitive sensor of a conventional steering wheel.

[0017] Figure 3 This is a cross-sectional view of a structure in which a capacitive sensor is provided around a heater of a conventional steering wheel.

[0018] Figure 4 It is a perspective view of the steering wheel of the first form of this embodiment.

[0019] Figure 5 It is an explanatory diagram of the detection area of ​​the steering wheel sensor according to the first aspect of the present embodiment.

[0020] Figure 6 It is a partially exploded perspective view of a steering wheel sensor according to a first aspect of the present embodiment.

[0021] Figure 7 This is a block diagram of a steering wheel sensor according to a first aspect of the present embodiment.

[0022] Figure 8 It is an explanatory diagram of the detection area of ​​the steering wheel sensor according to the second aspect of the present embodiment.

[0023] Fig. 9 This is a block diagram of a steering wheel sensor according to a second aspect of the present embodiment. DETAILED DESCRIPTION

[0024] The following describes the implementation method. In addition, the same reference numerals are given to the same components and the description thereof is omitted.

[0025] (Explanation of conventional steering wheels)

[0026] First, based on Figures 1 to 3 A conventional steering wheel is described below. Figure 1 As shown, a steering wheel generally used for a vehicle has an annular portion called a rim 10 and a portion called a spoke 20 connected to the inner side of the rim 10 and connected to a rotating shaft not shown. When driving a vehicle, a person generally holds the rim 10 of the steering wheel and operates the steering wheel by rotating it. However, in the recent market, research is being conducted on introducing an automatic driving function into a vehicle. However, at present, the automatic driving function is positioned as a driving auxiliary function at best, and even if the vehicle has the automatic driving function, it is prohibited by law for the driver to take his hands off the steering wheel. In connection with this situation, a vehicle with an automatic driving function preferably has a function of detecting and judging whether the driver's hands are placed in a position where the steering wheel can be immediately operated, and has a function of prompting the driver to pay attention when the result of the judgment is negative. Therefore, as a specific example for detecting whether a person's hands are holding the steering wheel, a structure in which a sensor such as an electrostatic capacitive sensor is arranged inside the rim 10 of the steering wheel is considered.

[0027] However, there are cases where the vehicle is used in cold places. In this case, for example, if the steering wheel is too cold compared to the human body temperature, the person will feel cold when the hand touches the steering wheel, and sometimes it will cause obstacles to driving the vehicle without long-term contact. Therefore, it is considered to provide a heater inside the rim 10 of the steering wheel, and heat the rim 10 of the steering wheel to make it warm when driving the vehicle. As such a heater, for example, a heating element such as a heating wire that generates heat by passing an electric current is cited. Such a heating element generates heat through the resistance component of the heating element, and is formed of materials such as metals with relatively high resistance such as nickel-chromium alloys.

[0028] Therefore, in this case, both a heater and a sensor such as an electrostatic capacitive sensor are arranged inside the rim 10 of the steering wheel. When a heater is arranged inside the rim 10 of the steering wheel, where a person's hand holds the rim 10 of the steering wheel varies from person to person, and it is preferable to provide a heater at a portion that is considered to be held by a person. Similarly, regarding sensors such as an electrostatic capacitive sensor, where a person's hand holds the rim 10 of the steering wheel varies from person to person, and it is preferable to provide a sensor such as an electrostatic capacitive sensor at a portion that is considered to be held by a person.

[0029] Therefore, inside the rim 10 of the steering wheel, both the heater and the sensor such as the electrostatic capacitance sensor are arranged in the same range on the circumference of the rim, with one being inside the other. Figure 2A cross-sectional view of a structure in which a heater is provided around a capacitive sensor of a conventional steering wheel, and Figure 3 A cross-sectional view of a structure in which a capacitive sensor is provided around a heater of a conventional steering wheel will be described.

[0030] For example, Figure 2 The structure shown is a structure in which a capacitive sensor 30 is provided around a core 11 forming the center part of the rim 10 of the steering wheel, a heater 40 is provided around the capacitive sensor 30, and a skin part 50 is provided around the heater 40. In this case, the electrostatic capacitance of the capacitive sensor 30 changes when a human hand touches or approaches the rim 10 of the steering wheel. In addition, a control unit (not shown) electrically connected to the capacitive sensor 30 detects the change in the electrostatic capacitance and generates a detection signal, and compares the detection signal with a preset threshold value, thereby determining whether a human hand touches or approaches the rim 10. However, a heater 40 composed of a resistor made of a conductive metal exists near the capacitive sensor 30. Generally, a conductive metal has a large electrostatic capacitance, and the heater 40 also has a large electrostatic capacitance. Therefore, when the heater 40 is arranged nearby, the tendency of the change in the electrostatic capacitance of the capacitive sensor 30 changes compared to the case where there is no influence of the heater 40. Therefore, the size of the detection signal generated by the control unit based on the change in the electrostatic capacitance of the electrostatic capacitance sensor 30 will change according to the influence of the heater 40. Therefore, there is a case where the judgment based on the control unit is not accurate. In addition, when the temperature changes, the value of the electrostatic capacitance detected in the electrostatic capacitance sensor 30 changes, so when the electrostatic capacitance sensor 30 is warmed by the heat from the heater 40, the detection signal detected by the control unit using the electrostatic capacitance sensor 30 changes compared to before heating. Therefore, the result of the judgment made by the control unit based on the detection signal sometimes becomes inaccurate.

[0031] in addition, Figure 3 The structure shown is a structure in which a heater 40 is provided around the core metal 11 forming the central part of the rim 10 of the steering wheel, an electrostatic capacitance type sensor 30 is provided around the heater 40, and a skin portion 50 is provided around the electrostatic capacitance type sensor 30. In this case, the heat generated from the heater 40 warms the skin portion 50 via the electrostatic capacitance type sensor 30 sandwiched therebetween, and is thereby transferred to the human hand, so that Figure 2 Compared with the structure shown, it takes time for the rim 10 to warm up, and the power consumed by the heater 40 also increases.

[0032] and, Figure 3 The structure shown is Figure 2 Similarly to the structure shown in the figure, there is a conductive heater 40 near the electrostatic capacitance sensor 30, so the size of the detection signal generated by the electrostatic capacitance sensor 30 becomes unstable, and the result of the judgment made by the control unit based on the detection signal may become inaccurate. Figure 3 The structure shown is Figure 2 Similarly to the structure shown, if the electrostatic capacitive sensor 30 is warmed by the heat from the heater 40, the intensity of the detection signal generated using the electrostatic capacitive sensor 30 will change compared with before heating, so the result of the judgment made by the control unit based on the detection signal may become inaccurate.

[0033] In the structure where the electrostatic capacitance sensor 30 is provided on the wheel rim 10 in this way, it is sometimes impossible to accurately determine whether the human hand is in contact with the steering wheel.

[0034] (Steering wheel sensor and steering wheel according to the first embodiment of the present invention)

[0035] Next, based on Figures 4 to 7 The steering wheel sensor 102 (an example of a "sensor device" described in the claims) and the steering wheel 100 (an example of a "steering wheel" described in the claims) of the first embodiment of the present invention are described. Figure 4 As shown, the steering wheel sensor 102 includes: a rim 110; a spoke 120 connected to the inner side of the rim 110 and connected to a rotating shaft (not shown); and a steering wheel sensor 102 provided on the spoke 120. The steering wheel sensor 102 includes: an electrostatic capacitance sensor 130 (an example of an "electrode" described in the claims) capable of capacitive coupling with an object to be detected having a capacitance value (hereinafter referred to as an operating body); and a control unit 160 (an example of a "control unit" described in the claims). In the first mode of the present embodiment, the electrostatic capacitance sensor 130 is provided along the edge portions 121a, 121b, and 121c of the spoke 120 facing the inner peripheral surface of the rim 110, and a heater 140 for heating the rim 110 to warm it is built into the rim 110. That is, the electrostatic capacitance sensor 130 and the heater 140 are provided in different parts of the steering wheel.

[0036] like Figure 7 As shown, the control unit 160 is electrically connected to the electrostatic capacitive sensor 130 .

[0037] In the first mode of the present embodiment, the control unit 160 generates a detection signal based on the change in the electrostatic capacitance of the electrostatic capacitance sensor 130, and further performs coding processing on the detection signal to facilitate transmission in communication. Figure 7The external device communicates with the external device shown and transmits the detection signal. The external device compares the detection signal with a preset threshold value to determine whether the driver's hand is placed in a position where the steering wheel can be immediately operated. If the result of this determination is no, the driver is prompted to pay attention.

[0038] In addition, the control unit 160 may be responsible for determining whether the driver's hands are placed in a position where the steering wheel can be immediately operated.

[0039] In this way, the steering wheel 100 is configured by separating the electrostatic capacitance sensor 130 from the heater 140, so that the tendency of the change in the electrostatic capacitance of the electrostatic capacitance sensor 130 is hardly affected by the electrostatic capacitance of the heater 140. In addition, the detection signal generated by the control unit 160 based on the change in the electrostatic capacitance of the electrostatic capacitance sensor 130 is hardly affected by the electrostatic capacitance of the heater 140. In addition, the heat from the heater 140 is hardly transferred to the electrostatic capacitance sensor 130, so the control unit 160 can accurately detect whether the human hand is in contact with or close to the steering wheel without being affected by the heater 140. In addition, the heater 140 can efficiently warm the rim 10 without being affected by the heat capacity of the electrostatic capacitance sensor 130.

[0040] In addition, the control unit 160 can detect whether an operating body with a capacitance value, mainly a human hand, is in contact or approaching through changes in the capacitance of the capacitance sensor 130. However, since the capacitance value of the capacitance sensor 130 depends on the distance between the capacitance sensor 130 and the operating body to be detected, it increases if the operating body approaches the capacitance sensor 130 and decreases if it moves away. Taking advantage of this, the control unit 160 can adjust the detection range by adjusting the threshold value compared with the value of the detection signal from the capacitance sensor 130 or using multiple threshold values ​​for judgment. Specifically, even when using Figure 4 Even when the portion (130a, 130b) constituting the electrostatic capacitive sensor 130 shown in FIG. 1 is the farthest from the rim 110, the control unit 160 can determine that the operating body is close to the rim 110. Therefore, for example, Figure 5 When there is an operating body between the rim 110 shown and the electrostatic capacitive sensors 130 arranged along the edges 121a, 121b, 121c of the spokes 120 opposite to the inner circumferential surface of the rim 110, and in the detection areas 150a, 150b, 150c set around the rim 110, the control unit 160 determines this situation.

[0041] In the first embodiment of the present invention, the electrostatic capacitive sensor 130 is built into the steering wheel sensor 102, and the driver's side of the steering wheel sensor 102 is Figure 6 The electrostatic capacitance sensor 130 is formed of a conductor such as a linear wire and is provided along the edge of the spoke 120. The detection areas 150a, 150b, and 150c are as shown in FIG. Figure 5 As shown, it expands along a plane direction including the rim 110 .

[0042] Furthermore, the rim 110 and the spoke 120 are specifically as follows: Figure 4 As shown in the figure, the inner side of the rim 110 and the spokes 120 are connected at the connection parts 120a, 120b, and 120c. Between the connection parts 120a and 120b of the spokes 120, a space is formed between the spokes 120 and the rim 110. Also, similarly, between the connection parts 120a and 120c of the spokes 120, a space is formed between the spokes 120 and the rim 110. Also, similarly, between the connection parts 120b and 120c of the spokes 120, a space is formed between the spokes 120 and the rim 110.

[0043] The steering wheel sensor 102 has a portion 130a (an example of a “segment” described in the claims) provided along the edge 121a of the spoke 120 that is opposite to the rim 110. In addition, it has a portion 130b (an example of a “segment” described in the claims) provided along the edge 121b of the spoke 120 that is opposite to the rim 110. In addition, it has portions 130c and 130d (an example of a “segment” described in the claims) that are partially provided along the edge 121c of the spoke 120 that is opposite to the rim 110. In addition, it has a portion 130e (an example of a “segment” described in the claims) provided at the connection portion 120a where the spoke 120 and the rim 110 are connected, and a portion 130f (an example of a “segment” described in the claims) provided along the connection portion 120b.

[0044] In addition, at the connecting portion 120a where the spoke 120 is connected to the rim 110, a portion 130e of the electrostatic capacitive sensor 130 (an example of a “segment” described in the claims) is provided along the connecting portion 120a, at the connecting portion 120b, a portion 130f of the electrostatic capacitive sensor 130 (an example of a “segment” described in the claims) is provided along the connecting portion 120b, and at the connecting portion 120c, a portion 130g of the electrostatic capacitive sensor 130 (an example of a “segment” described in the claims) is provided along the connecting portion 120c.

[0045] like Figure 6As shown, the electrostatic capacitive sensor 130 is formed by one wire or the like, and is formed in the order of part 130c, part 130f, part 130a, part 130e, part 130b, part 130g, and part 130d. In addition, in the first mode of the present embodiment, the electrostatic capacitive sensor 130 may also be formed by two wires or the like. For example, it may be formed by a structure formed by a part of part 130e, part 130a, part 130f, and part 130c, and a structure formed by another part of part 130e, part 130b, part 130g, and part 130d.

[0046] That is, the electrostatic capacitance sensor 130 is configured to include edge portions (121a, 121b) and connection portions (120a, 120b, 120c), and is continuously provided along the outer circumference of the spoke.

[0047] The first mode of this embodiment is a structure assuming that the person driving the vehicle mainly holds a part of the lower part 110a, 110b of the rim 110 to operate the vehicle. For example, when the lower part 110a of the rim 110 is held by a human hand, the human hand can be detected because the part 130a close to the electrostatic capacitive sensor 130 enters the detection area 150a. In addition, when the lower part 110b of the rim 110 is held by a human hand, the human hand can be detected because the part 130b close to the electrostatic capacitive sensor 130 enters the detection area 150b.

[0048] In addition, when a person drives a vehicle, the hand may touch the connection portion of the spoke 120 with the rim 110 or its vicinity to operate. For example, when the hand of the person touches the connection portion 120a of the spoke 120 or its vicinity, the hand of the person approaching the portion 130e of the electrostatic capacitance sensor 130 enters the detection area 150a or the detection area 150b, and is thus detected by the control unit 160. Alternatively, the hand of the person approaching the portion 130e of the electrostatic capacitance sensor 130 approaches the connection portion 120a side of the portion 130a of the electrostatic capacitance sensor 130 or the connection portion 120a side of the portion 130b of the electrostatic capacitance sensor 130 and enters the detection area 150a or the detection area 150b, and is thus detected by the control unit 160.

[0049] In addition, when the human hand touches the connection portion 120b of the spoke 120 or its vicinity, the human hand approaches the portion 130f, portion 130c, etc. of the electrostatic capacitive sensor 130 and enters the detection area 150c, and is thus detected by the control unit 160. When the human hand touches the connection portion 120c of the spoke 120 or its vicinity, the human hand approaches the portion 130g, portion 130d, etc. of the electrostatic capacitive sensor 130 and enters the detection area 150d, and is thus detected by the control unit 160.

[0050] (Steering wheel sensor and steering wheel according to the second embodiment of the present invention)

[0051] Below, use Figure 8 , Fig. 9 A steering wheel sensor and a steering wheel according to a second embodiment of the present embodiment will be described, but the same components as those of the first embodiment are given the same reference numerals.

[0052] The second method of this implementation is to assume that the person driving the vehicle mainly holds Figure 8 The structure of the vehicle is operated by a part of the upper portion 110c of the annular rim 110 shown.

[0053] In the second mode of this implementation, if Figure 8 As shown, the steering wheel 100 includes an annular rim 110, a spoke 120 disposed inside the rim 110, and a steering wheel sensor 102 disposed on the spoke 120. The rim 110 and the spoke 120 are connected via connecting portions 120a, 120b, and 120c.

[0054] The steering wheel sensor 102 has an electrostatic capacitance sensor 130 (an example of an "electrode" described in the claims) which is disposed along the edge of the spoke 120 opposite to the inner circumference of the rim 110 and can be capacitively coupled with an object to be detected (hereinafter, an operating body) having a capacitance value. In addition, similarly, it has an electrostatic capacitance sensor 131 (an example of an "electrode" described in the claims) which is disposed along the edge of the spoke 120 opposite to the inner circumference of the rim 110 and can be capacitively coupled with an operating body having a capacitance value. In addition, it has a control unit 160 which is electrically connected to the electrostatic capacitance sensor 130 and the electrostatic capacitance sensor 131.

[0055] The electrostatic capacitive sensor 130 has portions 130a and 130b (an example of a “segment” described in the claims) of the electrostatic capacitive sensor 130 provided along the lower edge portions 121a and 121b of the spoke 120 opposite to the inner peripheral surface of the rim 110. In addition, the electrostatic capacitive sensor 130 has an edge portion 121c along the upper side of the spoke 120 opposite to the inner peripheral surface of the rim 110, a portion 130c (an example of a “segment” described in the claims) of the electrostatic capacitive sensor 130 provided on the connecting portion 120b side, and a portion 130d (an example of a “segment” described in the claims) of the electrostatic capacitive sensor 130 provided on the connecting portion 120c side.

[0056] The electrostatic capacitive sensor 130 is formed of one conductive wire, and is formed in the order of part 130c, part 130f, part 130a, part 130e, part 130b, part 130g, and part 130d of the electrostatic capacitive sensor 130. Each part of the electrostatic capacitive sensor 130 has a different resistance value depending on the distance from the rim 110.

[0057] The capacitive sensor 131 is provided along the upper edge 121 c of the spoke 120 facing the inner peripheral surface of the rim 110 , at a portion 130 c or a portion 130 d where the capacitive sensor 130 is not provided.

[0058] In the second aspect of the present embodiment, the capacitance sensor 130 and the capacitance sensor 131 are provided along the edge of the spoke 120 so as not to overlap each other, but they may be provided so as to overlap each other within a range where erroneous detection does not occur.

[0059] like Fig. 9 As shown, the electrostatic capacitance sensor 130 and the electrostatic capacitance sensor 131 are connected in parallel to the control unit 160 .

[0060] The electrostatic capacitance sensor 131 has a resistance value different from that of the electrostatic capacitance sensor 130. Figure 8 As shown, the electrostatic capacitance sensor 131 is provided along the upper edge 121c of the spoke 120 and is separated from the connecting portion 120b and the connecting portion 120c. That is, the electrostatic capacitance sensor 131 is provided along the center of the upper edge 121c of the spoke 120. Therefore, in the case where the spoke 120 has a general shape (T-shaped shape), the distance from the rim 110 to the electrostatic capacitance sensor 131 is greater than the distance from the rim 110 to the electrostatic capacitance sensor 130. Therefore, the sensitivity of the detection using the electrostatic capacitance sensor 131 is preferably set to be higher than the sensitivity of the electrical detection using the electrostatic capacitance sensor 130.

[0061] When the operating body contacts or approaches the wheel rim 110, the capacitance of the capacitance sensor 130 or the capacitance sensor 131 changes. When the capacitance of the capacitance sensor 130 or the capacitance sensor 131 changes, the control unit 160 detects the change and generates a detection signal. Based on the detection signal, the control unit 160 or Fig. 9 The external device shown determines whether the operating body approaches the rim 110. At this time, the control unit 160 makes a determination by comparing the detection signal with a threshold value set based on the distance from the rim 110 to the electrostatic capacitance sensors 130 and 131.

[0062] like Figure 8As shown, detection areas 150 a , 150 b , and 150 c are set around the rim 110 and in the space between the rim 110 and the capacitive sensor 130 so as to extend along a plane direction including the rim 110 .

[0063] When the operating body is present in the detection area 150a, the detection area 150b, the detection area 150c, or the detection area 150d, the control unit 160 detects the change in capacitance of the capacitance sensor 130 or the capacitance sensor 131 that changes accordingly, and generates a detection signal.

[0064] Control unit 160 or Fig. 9 The external device shown makes a determination based on the detection signal.

[0065] As mentioned above, although embodiment is described in detail, the invention of this application is not limited to a specific embodiment, Various deformation|transformation and change are possible within the range described in a claim.

[0066] This international application claims the benefit of priority based on Japanese Patent Application No. 2019-057316, filed on March 25, 2019, the entire contents of which are incorporated herein by reference.

[0067] Description of Reference Numerals

[0068] 100 Steering Wheel

[0069] 102 Steering wheel sensor

[0070] 110 rim

[0071] 110a, 110b The lower part of the rim

[0072] 110c Upper part of the rim

[0073] 120 spokes

[0074] 120a, 120b, 120c connection part

[0075] 121a, 121b, 121c edge

[0076] 125 appearance panel

[0077] 130, 131 electrostatic capacitive sensor

[0078] 130a, 130b, 130c, 130d, 130e, 130f, 130g capacitive sensor part

[0079] 140 Heater

[0080] 150a, 150b, 150c, 150d detection area

[0081] 160 Control Department

Claims

1. A sensor device for detecting the contact or approach of a driver's hand to a steering wheel, characterized in that: The steering wheel has a rim and spokes connected to an inner side of the rim, The sensor device comprises: Electrodes, arranged on the spokes of the steering wheel, capable of capacitive coupling with the driver's hand to be detected; and a control unit that detects a change in electrostatic capacitance of the electrode that occurs when the driver's hand contacts or approaches the wheel rim, Whether the driver's hand is in contact with or close to the wheel rim is determined based on the change in the electrostatic capacitance.

2. The sensor device according to claim 1, characterized in that The control unit generates a detection signal based on the change in the electrostatic capacitance, and communicates with an external device that determines whether the driver's hand is in contact with or close to the wheel rim based on the change in the electrostatic capacitance to transmit the detection signal.

3. The sensor device according to claim 1, characterized in that The control unit determines whether the driver's hand is in contact with or close to the wheel rim based on the change in the electrostatic capacitance.

4. The sensor device according to claim 1, characterized in that The electrode is formed of a linear conductor and is provided along an edge portion of the spoke facing the rim.

5. The sensor device according to claim 4, characterized in that The electrode is further arranged at a connection portion where the spoke is connected to the rim.

6. The sensor device according to claim 5, characterized in that The electrode is provided continuously along the outer circumference of the spoke including the edge portion and the connecting portion.

7. The sensor device according to any one of claims 1 to 6, characterized in that The electrode is formed by one or more electrical conductors along a plane including the rim.

8. The sensor device according to claim 1, characterized in that The electrode has a plurality of segments, each of which has a different resistance value based on a distance from the rim.

9. The sensor device according to claim 1, characterized in that The sensor device determines whether the driver's hand is in contact or approaching by comparing the signal from the electrode with a plurality of threshold values ​​set based on the distance from the wheel rim to the electrode.

10. The sensor device according to claim 1, characterized in that The detection area expands along a plane direction including the wheel rim.

11. The sensor device according to claim 1, characterized in that The sensor device is provided on the wheel spoke as a steering wheel sensor including the electrode and the control unit.

12. The sensor device according to claim 11, characterized in that The electrode is formed of a linear conductor and is provided along an edge of the steering wheel sensor facing the wheel rim.

13. The sensor device according to claim 12, characterized in that The electrode is disposed at a portion where the steering wheel sensor is connected to the wheel rim.

14. The sensor device according to claim 13, characterized in that The electrode is provided continuously along the outer circumference of the steering wheel sensor configured to include the edge portion and the connecting portion.

15. The sensor device according to claim 11, characterized in that The steering wheel sensor integrally includes the electrodes in both left and right regions of the steering wheel.

16. The sensor device according to claim 11, characterized in that The steering wheel sensor has one or more detection areas extending along a plane direction including the wheel rim.

17. A steering wheel, characterized in that: A sensor device according to any one of claims 1 to 16.

18. A steering wheel, characterized in that: have: The sensor device according to any one of claims 1 to 16; and The heater is disposed inside the rim and heats the rim.

Images