Detection device for steering

Abstract

This detection device for steering comprises: a decorative member that is provided in an operation unit of the steering which is used for steering a vehicle; a detection electrode that is provided on the decorative member and is used to detect the electrocardiogram of a driver; and a DRL electrode that is provided on the decorative member and removes noise input to the detection electrode.

Description

Steering detection device

[0001] The present disclosure relates to a steering detection device.

[0002] A steering wheel provided with an electrocardiogram detector that detects the driver's electrocardiogram is known (see, for example, Japanese Patent Application Laid-Open No. 2016-203660).

[0003] Japanese Patent Application Laid-Open Publication No. 2016-203660 discloses a grip detection device including a first electrode and a second electrode provided on a steering wheel of a vehicle, and a heartbeat detection unit that detects the heartbeat of a driver who is in contact with the first electrode and the second electrode based on a voltage pattern obtained from the first electrode and the second electrode.

[0004] In such a steering detector, it is preferable to detect the driver's electrocardiogram using a decorative member provided on the steering wheel.

[0005] The present disclosure provides a steering detector that can detect a driver's electrocardiogram using a decorative member provided on the steering wheel.

[0006] A steering detection device according to a first aspect of the present disclosure includes a decorative member provided on an operating portion of a steering wheel that steers a vehicle, a detection electrode provided on the decorative member and used to detect the driver's electrocardiogram, and a DRL electrode provided on the decorative member that removes noise input to the detection electrode.

[0007] In a steering detection device of a second aspect of the present disclosure, in the steering detection device of the first aspect of the present disclosure, the detection electrode and the DRL electrode have an overlapping portion in which a portion of the position in the circumferential direction of the steering wheel overlaps.

[0008] In a steering detection device of a third aspect of the present disclosure, in the steering detection device of the second aspect of the present disclosure, the detection electrode has a first tapered portion at its tip, the DRL electrode has a second tapered portion at its tip, and the overlapping portion is formed by the first tapered portion and the second tapered portion.

[0009] In a steering detection device of a fourth aspect of the present disclosure, in the steering detection device of any one of the first to third aspects of the present disclosure, the detection electrode and the DRL electrode are arranged in series in the circumferential direction of the steering wheel.

[0010] A steering detection device according to a fifth aspect of the present disclosure is the steering detection device according to the second aspect of the present disclosure, wherein the overlapping portion is formed at a position spanning an upper surface of a spoke of the steering wheel.

[0011] In a steering detection device of a sixth aspect of the present disclosure, in the steering detection device of the fifth aspect of the present disclosure, the upper electrode of the detection electrode and the DRL electrode has a protrusion that is continuous with the upper surface of the spoke and protrudes inward of the steering wheel.

[0012] In a steering detection device of a seventh aspect of the present disclosure, in any one of the steering detection devices of the first to fifth aspects of the present disclosure, a grip electrode used to detect the grip of the steering wheel is arranged in a position that does not overlap with the detection electrode and the DRL electrode when viewed from the radial direction of the operating unit.

[0013] The steering detector of the first aspect of the present disclosure includes a detection electrode provided on the decorative member and used to detect the driver's electrocardiogram, and a DRL electrode provided on the decorative member and used to remove noise input to the detection electrode, so that the detection electrode and the DRL electrode are disposed on the decorative member, thereby enabling the driver's electrocardiogram to be detected by the decorative member.

[0014] In the steering detection device of the second aspect of the present disclosure, the detection electrode and the DRL electrode have an overlapping portion where they partially overlap in the circumferential direction of the steering wheel, so that a portion of the detection electrode overlaps a portion of the DRL electrode in the circumferential direction of the steering wheel. Therefore, compared to a case where the detection electrode and the DRL electrode are not positioned so as to overlap in the circumferential direction of the steering wheel, the area where the driver's hands come into contact with both the detection electrode and the DRL electrode when the driver grips the steering wheel is wider. As a result, the detection accuracy of the driver's electrocardiogram can be improved.

[0015] In the steering detector of the third aspect of the present disclosure, the overlapping portion is formed by a first tapered portion and a second tapered portion, so that the first tapered portion and the second tapered portion are overlapped at a position in the circumferential direction of the steering wheel. This allows for a compact configuration, and increases the area where the driver's hands come into contact with both the detection electrode and the DRL electrode when the driver grips the steering wheel. As a result, the accuracy of detecting the driver's electrocardiogram can be improved with a compact configuration.

[0016] In the steering detection device according to the fourth aspect of the present disclosure, the detection electrodes and the DRL electrodes are arranged in series in the circumferential direction of the steering wheel, which reduces the arrangement width compared to when the detection electrodes and the DRL electrodes are arranged in parallel, thereby reducing the width of the decorative member on which the detection electrodes and the DRL electrodes are arranged.

[0017] In the steering detector of the fifth aspect of the present disclosure, the overlapping portion is formed at a position that straddles the upper surface of the spoke of the steering wheel, so that the overlapping portion is formed at a position where the driver tends to grip the steering wheel, thereby improving the detection accuracy of the driver's electrocardiogram.

[0018] In a sixth aspect of the steering detector of the present disclosure, the upper electrode of the detection electrode and the DRL electrode has a protrusion that is continuous with the upper surface of the spoke and protrudes toward the inside of the steering wheel, so that one electrode is arranged to protrude continuously with the upper surface of the spoke. Therefore, the driver's hand comes into contact with both the detection electrode and the DRL electrode both when the driver operates the steering wheel by placing his / her thumb on the rim and when the driver operates the steering wheel by wrapping his / her thumb around the protrusion. As a result, the detection accuracy of the driver's electrocardiogram can be improved with a simple configuration.

[0019] In a sixth aspect of the present disclosure, the steering detector is configured such that the grip electrodes used to detect the driver's grip on the steering wheel are positioned so as not to overlap with the detection electrodes and the DRL electrodes when viewed from the radial direction of the operation unit. This allows the detection electrodes and the DRL electrodes to be detected without interfering with detection by the grip electrodes. This improves the detection accuracy of both the driver's grip and the driver's electrocardiogram.

[0020] 1 is a front view showing a steering wheel to which a steering detection device according to an embodiment is applied; FIG. 2 is a cross-sectional view showing the steering wheel according to an embodiment, showing the A-A cross section in FIG. 1; FIG. 3 is a plan view showing the right portion of the steering wheel according to an embodiment, showing a state in which a driver is holding the steering wheel in a first position; and FIG. 4 is a plan view showing the right portion of the steering wheel according to an embodiment, showing a state in which a driver is holding the steering wheel in a second position.

[0021] Hereinafter, a steering detector according to an embodiment will be described with reference to the drawings. In each drawing, an arrow UP indicates the upper side of the steering wheel 5, and an arrow RH indicates the right side of the steering wheel 5.

[0022] [Steering Configuration] The steering wheel 5 (e.g., a steering wheel) is provided at the front of the vehicle interior, facing the driver's seat. The steering wheel 5 is located in front of the driver (driver, human body) seated in the driver's seat. The front, upper, and right sides of the steering wheel 5 are oriented toward the rear, upper, and right sides of the vehicle, respectively.

[0023] As shown in FIG. 1, the steering wheel 5 includes a boss 12, a rim 16 as an actuator, and spokes 14 as connecting portions.

[0024] (Boss portion 12) The boss portion 12 is located in the center of the steering wheel 5. The boss portion 12 is fixed to the rear end (upper end) of the vehicle of a cylindrical steering shaft 11, which serves as a support member for the vehicle. The steering shaft 11 is located coaxially with the rim portion 16. The steering wheel 5 is supported by the steering shaft 11 so as to be rotatable integrally therewith, and when the driver grips the rim portion 16 and rotates the steering wheel 5 in the circumferential direction, the steering shaft 11 rotates about the central axis, and the vehicle is steered.

[0025] (Rim portion 16) The rim portion 16 has an annular shape in front view and a generally circular cross section, and is formed as the periphery of the steering wheel 5. As shown in Fig. 2, the rim portion 16 includes a core metal 16A, an elastic body 16B, and a skin 16C.

[0026] The core 16A is made of metal and has a substantially circular cross section, and forms the framework of the steering wheel 5. The elastic body 16B is made of, for example, polyurethane, and is disposed radially outward of the core 16A to cover the core 16A. The skin 16C is made of natural leather or synthetic leather, and is disposed radially outward of the elastic body 16B to cover the elastic body 16B.

[0027] [Configuration of Steering Detector 10 ] As shown in FIG. 1 , the steering detector 10 includes a garnish 20 as a decorative member, a grip electrode 30 , and an ECU (Electronic Control Unit) 32 .

[0028] 2 and 3, the garnish 20 is formed in the shape of a long plate extending in the circumferential direction of the steering wheel 5, and a pair of garnishes 20 are provided on the left and right sides of the rim portion 16. The garnishes 20 are arranged on the front side of the right side of the rim portion 16 and on the inner circumferential side of the steering wheel 5, and on the front side of the left side of the rim portion 16 and on the inner circumferential side of the steering wheel 5. The pair of left and right garnishes 20 are fitted into recesses 16D of the rim portion 16. The front side of the garnish 20 is flush with the circumferential surface of the rim portion 16, and constitutes part of the rim portion 16.

[0029] The right garnish 20 is arranged from above the connection portion between the rim portion 16 and the right spoke 14 to below the connection portion between the rim portion 16 and the right spoke 14. In other words, the right garnish 20 is arranged so as to straddle the connection portion between the right spoke 14 and the rim portion 16.

[0030] The left garnish 20 is arranged from above the connection portion between the rim portion 16 and the left spoke 14 to below the connection portion between the rim portion 16 and the left spoke 14. In other words, the left garnish 20 is arranged so as to straddle the connection portion between the left spoke 14 and the rim portion 16. The right and left garnishes 20 have the same configuration except that they are formed symmetrically, and the following description will mainly focus on the right garnish 20.

[0031] The garnish 20 includes a frame member 22 , a detection electrode 26 , and a DRL electrode (Driven Right Leg electrode) 24 .

[0032] 2 and 3 , the frame member 22 is formed from an insulating member (e.g., insulating resin) into a long plate shape extending in the circumferential direction of the steering wheel 5. The frame member 22 has a first recess 22A into which the DRL electrode 24 fits, and a second recess 22B into which the detection electrode 26 fits. The frame member 22 insulates the detection electrode 26 from the DRL electrode 24.

[0033] <Detection electrode 26> As shown in Figures 2 and 3, the detection electrode 26 is used to detect the driver's electrocardiogram. The detection electrode 26 is made of conductive resin with a fibrous conductive material mixed into the resin, thereby providing electrical conductivity. The detection electrode 26 and the DRL electrode 24 are arranged in series in the circumferential direction of the steering wheel 5. The detection electrode 26 is arranged below the DRL electrode 24. The detection electrode 26 is arranged in a lower portion of the garnish 20. The detection electrode 26 is formed in the shape of a long plate extending in the circumferential direction of the steering wheel 5 in a front view.

[0034] The detection electrode 26 has a first tapered portion 26A that tapers toward its upper end (tip). The first tapered portion 26A is disposed above the top surfaces 14A of the spokes 14 to below the top surfaces 14A of the spokes 14. The first tapered portion 26A tapers toward the outside in the radial direction of the steering wheel 5.

[0035] The detection electrodes 26 are electrically connected via lead wires to an ECU (Electronic Control Unit) 32 serving as a detection unit. The ECU 32 detects the differential voltage (potential difference) between the left and right detection electrodes 26 to detect the driver's electrocardiogram waveform.

[0036] 2 and 3 , the DRL electrode 24 removes noise input to the detection electrode 26. The DRL electrode 24 is made of a conductive resin and is therefore conductive. The DRL electrode 24 is disposed in an upper portion of the garnish 20. The DRL electrode 24 is formed in the shape of an elongated plate extending in the circumferential direction of the steering wheel 5 in a front view.

[0037] The DRL electrode 24 has, at its upper portion, a thumb rest portion 24C that protrudes radially inward of the steering wheel 5. The thumb rest portion 24C is a portion on which the driver places his or her thumb when operating the steering wheel 5.

[0038] The DRL electrode 24 has a second tapered portion 24A that tapers toward the lower end (tip). The second tapered portion 24A is disposed from above the top surfaces 14A of the spokes 14 to below the top surfaces 14A of the spokes 14. The second tapered portion 24A tapers toward the inside in the radial direction of the steering wheel 5.

[0039] The first tapered portion 26A and the second tapered portion 24A form an overlapping portion 25 where they overlap in the circumferential direction of the steering wheel 5. That is, the detection electrode 26 and the DRL electrode 24 have an overlapping portion 25 where they partially overlap in the circumferential direction of the steering wheel 5.

[0040] The overlapping portions 25 are disposed above the top surfaces 14A of the left and right spokes 14 and below the top surfaces 14A of the left and right spokes 14. In other words, the overlapping portions 25 are formed at positions that straddle the top surfaces 14A of the left and right spokes 14.

[0041] The DRL electrode 24 is continuous with the upper surface 14A of the spoke 14 and has a protrusion 24B that protrudes radially inward of the steering wheel 5.

[0042] The DRL electrodes 24 are electrically connected via lead wires to the ECU 32. The ECU 32 inverts and amplifies common-mode signal noise that has entered the pair of left and right detection electrodes 26 via the driver, and feeds back the noise-removed signal to the driver via the pair of left and right DRL electrodes 24.

[0043] 1 and 2, a pair of left and right grip electrodes 30 are provided on the rim portion 16. The grip electrodes 30 are arranged between the elastic body 16B and the surface 16C. The pair of left and right grip electrodes 30 extend along the outer peripheral edge of the steering wheel 5. The right grip electrode 30 extends from the lower end of the rim portion 16, via the right end of the rim portion 16, to the upper end of the rim portion 16. The left grip electrode 30 extends from the lower end of the rim portion 16, via the left end of the rim portion 16, to the upper end of the rim portion 16.

[0044] The pair of left and right grip electrodes 30 are arranged radially outward of the steering wheel 5 from the detection electrode 26 and the DRL electrode 24. The pair of left and right grip electrodes 30 are arranged in positions that do not overlap with the detection electrode 26 and the DRL electrode 24 when viewed from the radial direction of the rim portion 16.

[0045] The grip electrode 30 is electrically connected via lead wires to an ECU 32, which serves as a detection unit. The ECU 32 detects an increase in capacitance when the driver's hands or fingers approach the rim portion 16, thereby detecting that the steering wheel 5 is being gripped.

[0046] [Operation of the steering detection device 10] (First position) As shown in Figure 3, in the first position, the driver grips the rim portion 16 with each hand 50 and performs a steering operation with the thumbs 52 resting on the thumb rest portion 24C. At this time, the driver's hands 50 contact the detection electrodes 26, and the driver's thumbs 52 contact the DRL electrodes 24. The driver's hands 50 also grip the portion of the rim portion 16 where the grip electrodes 30 are provided.

[0047] The ECU 32 then detects the driver's electrocardiogram waveform by detecting the differential voltage (potential difference) between the left and right detection electrodes 26. The ECU 32 also inverts and amplifies common-mode signal noise that has entered the pair of left and right detection electrodes 26 via the driver, and feeds back a noise-removed signal to the driver via the pair of left and right DRL electrodes 24. The ECU 32 also detects an increase in capacitance when the driver's hands or fingers approach the rim portion 16, thereby detecting whether the driver is gripping the steering wheel 5.

[0048] (Second Position) As shown in Figure 4, in the second position, the driver grips the rim portion 16 with both hands 50 and operates the steering wheel with their thumbs 52 placed on the protrusions 24B. At this time, the driver's hands 50 contact the detection electrodes 26, and the driver's thumbs 52 contact the DRL electrodes 24. The driver's hands 50 also grip the portions of the rim portion 16 where the grip electrodes 30 are provided.

[0049] The ECU 32 then detects the driver's electrocardiogram waveform by detecting the differential voltage (potential difference) between the left and right detection electrodes 26. The ECU 32 also inverts and amplifies common-mode signal noise that has entered the pair of left and right detection electrodes 26 via the driver, and feeds back a noise-removed signal to the driver via the pair of left and right DRL electrodes 24. The ECU 32 also detects an increase in capacitance when the driver's hands or fingers approach the rim portion 16, thereby detecting that the steering wheel 5 is being gripped.

[0050] [Operation] The steering detection device 10 of the embodiment includes a garnish 20 provided on the rim portion 16 of the steering wheel 5 that steers the vehicle, a detection electrode 26 provided on the garnish 20 and used to detect the driver's electrocardiogram, and a DRL electrode 24 provided on the garnish 20 that removes noise input to the detection electrode 26 (see Figure 1).

[0051] By providing the detection electrode 26, which is provided on the garnish 20 and is used to detect the electrocardiogram of the driver, and the DRL electrode 24, which is provided on the garnish 20 and removes noise input to the detection electrode 26, the detection electrode 26 and the DRL electrode 24 are arranged on the garnish 20. Therefore, the garnish 20 can detect the electrocardiogram of the driver.

[0052] In the steering detector 10 of the embodiment, the detection electrode 26 and the DRL electrode 24 have an overlapping portion 25 where a part of the detection electrode 26 and the DRL electrode 24 overlap in the circumferential direction of the steering wheel 5 (see FIG. 3).

[0053] The detection electrode 26 and the DRL electrode 24 have an overlapping portion 25 where they partially overlap in the circumferential direction of the steering wheel 5, so that a portion of the detection electrode 26 is arranged to overlap a portion of the DRL electrode 24 in the circumferential direction of the steering wheel 5. Therefore, compared to a case where the detection electrode 26 and the DRL electrode 24 are not arranged to overlap in the circumferential direction of the steering wheel 5, the area where the driver's hands come into contact with both the detection electrode 26 and the DRL electrode 24 when the driver grips the steering wheel 5 is wider. As a result, the detection accuracy of the driver's electrocardiogram can be improved.

[0054] In the steering detection device 10 of the embodiment, the detection electrode 26 has a first tapered portion 26A at its tip, the DRL electrode 24 has a second tapered portion 24A at its tip, and the overlap portion 25 is formed by the first tapered portion 26A and the second tapered portion 24A (see Figure 3).

[0055] The overlapping portion 25 is formed by the first tapered portion 26A and the second tapered portion 24A, so that the first tapered portion 26A and the second tapered portion 24A are positioned so as to overlap in the circumferential direction of the steering wheel 5. This allows for a compact configuration, and increases the area over which the driver's hands come into contact with both the detection electrode 26 and the DRL electrode 24 when the driver grips the steering wheel 5. As a result, the detection accuracy of the driver's electrocardiogram can be improved with a compact configuration.

[0056] In the steering detection device 10 of the embodiment, the detection electrode 26 and the DRL electrode 24 are arranged in series (see FIG. 3).

[0057] The detection electrode 26 and the DRL electrode 24 are arranged in series, which reduces the arrangement width compared to when the detection electrode 26 and the DRL electrode 24 are arranged in parallel, thereby making it possible to reduce the width of the garnish 20 in which the detection electrode 26 and the DRL electrode 24 are arranged.

[0058] In the steering detector 10 of the embodiment, the overlapping portion 25 is formed at a position across the upper surface 14A of the spoke 14 of the steering wheel 5 (see FIG. 3).

[0059] The overlapping portion 25 is formed at a position that straddles the upper surface 14A of the spoke 14 of the steering wheel 5, so that the overlapping portion 25 is formed at a position where the driver tends to grip the steering wheel 5. This improves the accuracy of detecting the driver's electrocardiogram.

[0060] In the steering detection device 10 of the embodiment, the upper electrode of the detection electrode 26 and the DRL electrode 24 has a protrusion 24B that is continuous with the upper surface 14A of the spoke 14 and protrudes inward of the steering wheel 5 (see Figure 3).

[0061] Of the detection electrodes 26 and DRL electrodes 24, the upper DRL electrode 24 has a protrusion 24B that is continuous with the upper surface 14A of the spoke 14 and protrudes inward of the steering wheel 5, so that the DRL electrode 24 is arranged to protrude and be continuous with the upper surface 14A of the spoke 14. Therefore, in both cases where the driver operates the steering wheel by placing his / her thumb on the rim portion 16 of the steering wheel 5 and where the driver operates the steering wheel by wrapping his / her thumb around the protrusion 24B, the driver's hand comes into contact with both the detection electrode 26 and the DRL electrode 24. As a result, the detection accuracy of the driver's electrocardiogram can be improved with a simple configuration.

[0062] In the steering detection device 10 of the embodiment, the grip electrode 30 used to detect the grip of the steering wheel 5 is positioned so as not to overlap with the detection electrode 26 and the DRL electrode 24 when viewed from the radial direction of the rim portion 16 (see Figure 1).

[0063] The grip electrode 30 used to detect the grip of the steering wheel 5 is disposed at a position that does not overlap with the detection electrode 26 and the DRL electrode 24 when viewed from the radial direction of the rim portion 16, so that the detection electrode 26, the DRL electrode 24, and the grip electrode 30 are disposed at different positions when viewed from the radial direction of the rim portion 16. Therefore, the detection electrode 26 and the DRL electrode 24 are detected without interfering with detection by the grip electrode 30. As a result, the detection accuracy of both the driver's grip and the driver's electrocardiogram can be improved.

[0064] Although the steering detection device has been described above based on the embodiment, the specific configuration is not limited to this embodiment, and design changes are permitted as long as they do not deviate from the gist of the invention according to each claim.

[0065] In the embodiment, the steering detection device 10 includes the grip electrode 30. However, the steering detection device does not need to include the grip electrode. In this case, the steering detection device may detect the driver's grip using the results of the detection electrode and the DRL electrode.

[0066] In the embodiment, the steering detection device 10 has been described as an example in which the detection electrode 26 is disposed below the DRL electrode 24. However, the detection electrode may be disposed above the DRL electrode 24. In this case, the detection electrode may be provided with a thumb rest portion and a protrusion.

[0067] In the embodiment, the DRL electrode 24 includes the protrusion 24B that protrudes radially inward of the steering wheel 5. However, the DRL electrode does not necessarily have to include the protrusion.

[0068] In the embodiment, the detection electrodes 26 are provided on a pair of left and right garnishes 20. However, the locations where the detection electrodes are provided are not limited to this example, and for example, one of the detection electrodes may be provided on the seat on which the driver sits.

[0069] In the embodiment, the DRL electrodes 24 are provided on a pair of left and right garnishes 20. However, the DRL electrodes may be provided on either the left or right garnish.

[0070] In the embodiment, an example has been shown in which the DRL electrode 24 includes the thumb rest portion 24C. However, the DRL electrode does not necessarily have to include the thumb rest portion.

[0071] In the embodiment, the detection electrode 26 and the DRL electrode 24 are formed from a conductive resin. However, the detection electrode and the DRL electrode may be formed from other conductive materials, such as metal, conductive rubber, conductive fiber, or conductive leather.

[0072] The disclosure of Japanese Patent Application No. 2024-011987, filed on January 30, 2024, is incorporated herein by reference in its entirety.

[0073] All publications, patent applications, and technical standards mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent application, or technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A steering detection device comprising: a decorative member provided on an operating section of a steering wheel that steers a vehicle; a detection electrode provided on the decorative member and used to detect the driver's electrocardiogram; and a DRL electrode provided on the decorative member that removes noise input to the detection electrode.

2. A steering detection device according to claim 1, wherein the detection electrode and the DRL electrode have an overlapping portion where a part of the detection electrode and the DRL electrode overlap in the circumferential direction of the steering wheel.

3. A steering detection device according to claim 2, wherein the detection electrode has a first tapered portion at its tip, the DRL electrode has a second tapered portion at its tip, and the overlapping portion is formed by the first tapered portion and the second tapered portion.

4. The steering detection device according to claim 1, wherein the detection electrode and the DRL electrode are arranged in series in the circumferential direction of the steering wheel.

5. A steering detection device according to claim 2, wherein the overlapping portion is formed at a position that straddles the upper surface of the spoke of the steering wheel.

6. A steering detection device according to claim 5, wherein the upper electrode of the detection electrode and the DRL electrode is provided with a protrusion that is continuous with the upper surface of the spoke and protrudes inward of the steering wheel.

7. A steering detection device according to claim 1, wherein the grip electrodes used to detect the grip of the steering wheel are arranged in a position that does not overlap with the detection electrodes and the DRL electrodes when viewed from the radial direction of the operating unit.

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