JP2021028221A - Steering wheel and sensor sheet - Google Patents

Abstract

To provide a steering wheel and a sensor sheet that prevent erroneous detection of a state of being gripped.SOLUTION: In a steering wheel 26 comprising a rim 42 and spoke 46, the rim 42 comprises: a plurality of spoke connections 48 connected to the spoke 46; and spoke non-connections 50 interposed adjacent spoke connections 48 and not connected to the spoke 46. On an outer peripheral part of the rim 42, electrostatic capacity sensors 56 are provided along a circumferential direction of a cross-section of the rim 42. The width, in a circumferential direction of a cross-section, of the electrostatic capacity sensor 56 provided on each spoke connection 48 is less than the width, in a circumferential direction of a cross-section, of the electrostatic capacity sensor 56 provided on each spoke non-connection 50.SELECTED DRAWING: Figure 2

Description

The present invention relates to a steering wheel provided on a vehicle and a sensor sheet of a capacitance sensor attached to the steering wheel.

There are vehicles that can switch between manual steering performed mainly by the driver and automatic steering performed mainly by the system. Such a vehicle detects whether or not the driver is in contact with (grasping) the steering wheel at a predetermined timing, for example, when returning from automatic steering to manual steering. A capacitance sensor is used to detect the contact of the steering wheel. Patent Documents 1 to 3 show a steering wheel provided with a capacitance sensor on the rim.

Japanese Patent No. 5816827 JP 2015-131544 JP 2015-147531

For example, during automatic steering, the driver may cover the steering wheel due to poor physical condition or the like. At such times, the driver's arm or elbow is expected to come into contact with the left and right parts of the rim. When switching from automatic steering control to manual steering control, the vehicle requires the driver to grip the steering wheel. At this time, if the capacitance sensor is provided at the contact point between the driver's arm and elbow in the rim, the capacitance sensor detects the contact of the human body with the steering wheel. As a result, there is a possibility that the driver may falsely detect that the steering wheel is gripped even though it is not gripped.

The present invention has been made in consideration of such a problem, and an object of the present invention is to provide a steering wheel and a sensor seat that prevent false detection of being gripped.

The first invention is
A steering wheel with rims and spokes
The rim comprises a plurality of spoke connecting portions connected to the spokes, and spoke non-connecting portions interposed between the spoke connecting portions adjacent to each other and not connected to the spokes.
A capacitance sensor is provided on the outer peripheral portion of the rim along the circumferential direction of the cross section of the rim.
The width in the cross-sectional circumferential direction of the capacitance sensor provided at the spoke connecting portion is narrower than the width in the cross-sectional circumferential direction of the capacitance sensor provided at the spoke non-connecting portion.

As in the above configuration, if the width of the capacitance sensor provided in the part where the driver is likely to contact the arm or elbow is narrower than the width of the capacitance sensor provided in the other part, the driver steers. Even if it covers the wheel, the capacitance sensor does not detect the capacitance caused by the contact of the human body with the steering wheel. Therefore, it is possible to prevent erroneous detection that the steering wheel is being gripped.

The second invention is
A sensor sheet made of a conductive member and attached to the rim of a steering wheel to form a capacitance sensor.
A first part extending from the longitudinal center of the sheet towards the two ends,
A second part extending from one end toward the center,
A third part extending from the other end toward the center,
The fourth part between the first part and the second part,
It consists of a fifth part between the first part and the third part.
The first portion, the second portion, and the third portion have a first width in the width direction of the sheet.
The fourth portion and the fifth portion have a second width in the width direction of the sheet.
The second width is narrower than the first width.

According to the above configuration, a sensing region and a dead region can be formed with respect to the rim by a simple structure and work such as attaching a sensor sheet, so that the manufacturing cost is reduced.

According to the first invention, it is possible to prevent erroneous detection that the steering wheel is being gripped. According to the second invention, the manufacturing cost can be reduced.

FIG. 1 is a configuration diagram of a vehicle including the steering wheel unit according to the present embodiment. FIG. 2 is a front view of the steering wheel according to the present embodiment. FIG. 3 is a rear view of the steering wheel according to the present embodiment. FIG. 4 is a sectional view taken along line IV-IV of the steering wheel shown in FIG. FIG. 5 is a sectional view taken along line VV of the steering wheel shown in FIG. FIG. 6 is a developed view of the sensor sheet. FIG. 7 is a flowchart of the processing operation performed by the steering wheel unit.

Hereinafter, the steering wheel and the sensor seat according to the present invention will be described in detail with reference to the accompanying drawings with reference to suitable embodiments.

[1 Vehicle 10 configuration]
As shown in FIG. 1, the steering wheel unit 12 according to the present embodiment is provided in the vehicle 10. The vehicle 10 can appropriately switch between manual steering in which the driver takes the lead in steering and automatic steering in which the system (automatic driving device 14) takes the lead in steering. In the present embodiment, it is assumed that the vehicle 10 is an autonomous driving vehicle in which the system can mainly perform driving and braking operations in addition to steering. In addition to the steering wheel unit 12, the vehicle 10 includes an automatic driving device 14, a traveling device 16, and a notification device 18.

The automatic operation device 14 is composed of an ECU, and includes an arithmetic unit such as a processor and a storage device such as a ROM or RAM. The automatic operation device 14 realizes various functions by executing a program stored in the storage device by the arithmetic unit. The automatic driving device 14 acquires information necessary for automatic driving, for example, external world information (detection results of a camera, radar, etc.), running state information (running speed, acceleration / deceleration) of the vehicle 10, navigation information, and the like from various sensors and devices. Then, a control instruction for automatically performing the driving, steering, and braking operations is output to the traveling device 16.

The traveling device 16 includes a driving force device 20, a steering device 22, and a braking device 24. The driving force device 20 has a driving force ECU and a driving source including an engine / driving motor. The driving force device 20 generates a driving force in response to an operation of the accelerator pedal performed by the driver or a drive control instruction output from the automatic driving device 14. The steering device 22 includes an electric power steering system (EPS) ECU and an EPS actuator. The steering device 22 generates a steering force in response to an operation of the steering wheel 26 performed by the driver or a steering control instruction output from the automatic driving device 14. The braking device 24 has a brake ECU and a brake actuator. The braking device 24 generates a braking force in response to the operation of the brake pedal performed by the driver or the control instruction of braking output from the automatic driving device 14.

The notification device 18 includes a notification ECU, a display device, an audio device, and a tactile device. The notification device 18 notifies the driver according to a notification instruction output from the automatic driving device 14 or the contact determination device 28 described later.

[2 Configuration of steering wheel unit 12]
The steering wheel unit 12 includes a steering wheel 26 and a contact determination device 28.

The contact determination device 28 is composed of an ECU, and includes a sensor circuit 30, an arithmetic unit 32 such as a processor, and a storage device 34 such as a ROM or RAM.

The sensor circuit 30 is electrically connected to the capacitance sensor 56 provided on the steering wheel 26. The sensor circuit 30 includes a power source that energizes the capacitance sensor 56, a measuring device (for example, a current sensor, etc.) that measures a detection value C corresponding to the magnitude of the capacitance detected by the capacitance sensor 56. A switch for switching on / off of energization of the capacitance sensor 56 is provided.

The arithmetic unit 32 realizes various functions by executing a program stored in the storage device 34. In the present embodiment, the arithmetic unit 32 functions as a general control unit 36, a contact detection unit 38, and a notification instruction unit 40. The integrated control unit 36 performs processing other than the processing performed by the contact detection unit 38 and the notification instruction unit 40 regarding the contact detection processing of the human body with respect to the steering wheel 26. The contact detection unit 38 detects whether or not the human body is in contact with the steering wheel 26 according to the detection value C in the measuring device of the sensor circuit 30. The notification instruction unit 40 issues a notification instruction to the notification device 18 when the contact detection unit 38 does not detect the contact of the human body (driver) with the steering wheel 26 at the timing when the driver must grip the steering wheel 26. Output.

In addition to the various programs, the storage device 34 stores a first threshold value and a second threshold value (> first threshold value) as determination threshold values for whether or not the human body is in contact with the steering wheel 26.

[3 Configuration of steering wheel 26]
The front view and the rear view of the steering wheel 26 shown in FIGS. 2 and 3 show the operating state (posture) of the steering wheel 26 when the vehicle 10 travels straight. Hereinafter, this operation state (posture) is referred to as a neutral state. In FIG. 2, the vertical direction of the paper surface is the vertical direction of the steering wheel 26 in the neutral state, and the horizontal direction of the paper surface is the horizontal direction of the steering wheel 26 in the neutral state. Further, the front direction of the paper surface is the front direction of the steering wheel 26 in the neutral state, and the back direction of the paper surface is the back direction of the steering wheel 26 in the neutral state. In FIG. 3, the front-back and left-right directions are opposite to those in FIG. In addition, in FIGS. 2 and 3, the rim leather 60 (see FIGS. 5 and 6) on the substantially left half of the rim 42 is removed in order to make it easier to understand the arrangement of the electrodes, which is one of the features of the present invention. Indicates the state. The structure of the rim 42 of the steering wheel 26 is the same on the left and right.

As shown in FIGS. 2 and 3, the steering wheel 26 has a rim 42 formed in an annular shape, a hub 44 connected to a steering shaft (not shown), and spokes 46 interposed between the rim 42 and the hub 44. And have. The steering wheel 26 of the present embodiment has three spokes 46 extending from the hub 44 toward the rim 42 in the left-right direction and the downward direction. The number of spokes 46 may be other than three, and the extending directions thereof do not have to be the left-right direction and the downward direction.

The rim 42 comprises three spoke connecting portions 48 connected to the spokes 46 and a spoke non-connecting portion 50 that is interposed between the spoke connecting portions 48 adjacent to each other and is not connected to the spokes 46. In FIGS. 2 and 3, the boundary between the spoke connecting portion 48 and the spoke non-connecting portion 50 is indicated by an alternate long and short dash line. The spoke connecting portion 48 located on the left side of the rim 42 in the neutral state is referred to as the left spoke connecting portion 48L, the spoke connecting portion 48 located on the right portion is referred to as the right spoke connecting portion 48R, and the spoke connecting portion 48 located on the lower portion is referred to as the right spoke connecting portion 48R. Is referred to as a lower spoke connection portion 48B. The rigidity of the spoke connecting portion 48 is higher than that of the spoke non-connecting portion 50.

The rim 42 has a laminated structure having a plurality of layers in cross section (cross section parallel to the central axis of the steering wheel 26). As shown in FIG. 4, in the spoke non-connecting portion 50, the entire rim core metal 52 corresponding to the skeleton is covered with the rim resin 54, and a part of the rim resin 54 is covered with the capacitance sensor 56. The remaining part of 54 is covered with the elastic member 58, and the capacitance sensor 56 and the elastic member 58 are covered with the rim leather 60. The capacitance sensor 56 corresponds to an electrode made of a conductive member and is insulated from surrounding members. The capacitance sensor 56 and the elastic member 58 have substantially the same thickness.

As shown in FIG. 5, the right-spoke connecting portion 48R and the left-spoke connecting portion 48L (hereinafter, referred to as the right-spoke connecting portion 48R and the like) have a rim core metal 52 and a rim resin 54, similarly to the spoke non-connecting portion 50. It has a capacitance sensor 56, an elastic member 58, and a rim leather 60. In the right spoke connection portion 48R or the like, the rim core metal 52 is connected to the spoke core metal 62, the rim resin 54 is connected to the spoke resin 64, the rim leather 60 is connected to the spoke leather 66, and the elastic member 58 is on the front side. And a part of the back side. The structure of the lower spoke connecting portion 48B (the cross section is not shown) is substantially the same as the structure of the right spoke connecting portion 48R and the like except that the capacitance sensor 56 is not provided.

As shown in FIGS. 4 and 5, a portion located on the outer peripheral side of the rim 42 is defined as an outer peripheral portion with a surface S extending in the front-rear direction (front direction and back direction) from the central portion O2 of the cross section of the rim 42 as a boundary. It is referred to as 68, and the portion located on the inner peripheral side of the rim 42 is referred to as the inner peripheral portion 70. Further, the portion of each member located on the outermost circumference is referred to as an outer edge portion 72.

As shown in FIG. 4, in the spoke non-connecting portion 50, the capacitance sensor 56 is formed on the outer peripheral portion 68 and a part of the inner peripheral portion 70 of the rim 42. The capacitance sensor 56 extends around the outer edge 72 of the rim resin 54 along the circumferential direction of the cross section of the rim resin 54, and covers the surface of the outer peripheral portion 68 of the rim resin 54 and a part of the inner peripheral portion 70. That is, in the spoke non-connecting portion 50, the capacitance sensor 56 covers the entire surface of the rim resin 54 on the outer peripheral side of the surface S and a part of the surface of the rim resin 54 on the inner peripheral side of the surface S.

As shown in FIG. 5, in the right spoke connection portion 48R and the like, the capacitance sensor 56 is formed on a part of the outer peripheral portion 68 of the rim 42. The capacitance sensor 56 spreads around the outer edge portion 72 of the rim resin 54 along the circumferential direction of the cross section of the rim resin 54 and covers a part of the surface of the outer peripheral portion 68 of the rim resin 54. That is, in the right spoke connection portion 48R or the like, the capacitance sensor 56 covers only a part of the surface of the rim resin 54 on the outer peripheral side of the surface S, and covers the surface of the rim resin 54 on the inner peripheral side of the surface S. Absent.

The second width W2 in the cross-sectional circumferential direction of the capacitance sensor 56 provided in the spoke connecting portion 48 is narrower than the first width W1 in the cross-sectional circumferential direction of the capacitance sensor 56 provided in the spoke non-connecting portion 50 (FIG. 6).

The location of the capacitance sensor 56 in the rim 42 is the sensing area 100 that detects the contact of the human body with the steering wheel 26. Further, the place where the capacitance sensor 56 is not arranged is a dead area 102 that does not detect the contact of the human body with the steering wheel 26.

As shown in FIGS. 2 to 5, the sensing area 100 is on the outer peripheral side of the rim 42, except for the lower spoke connecting portion 48B, which is located relatively lower in the rim 42 when the steering wheel 26 is in the neutral state. Is formed. On the other hand, when the steering wheel 26 is in the neutral state, the left portion located relatively to the left in the rim 42, that is, the left spoke connecting portion 48L and the left portion via the central portion O1 on the front surface of the rim 42. A dead region 102 is formed on the right portion facing the right portion, that is, the right spoke connecting portion 48R.

In the present embodiment, the sensing region 100 is formed in a part of the outer peripheral portion 68 and the inner peripheral portion 70 in the spoke non-connecting portion 50, while one of the inner peripheral portion 70 and the outer peripheral portion 68 in the right spoke connecting portion 48R or the like. A dead region 102 is formed in the portion. In other words, in the present embodiment, the direct front is the sensing area 100 in the spoke non-connecting portion 50, while the direct front is the insensitive region 102 in the right spoke connecting portion 48R and the like.

In the present embodiment, the left portion includes the leftmost portion in the neutral state. Here, the left portion is sandwiched between a portion that is displaced upward by about 40 ° along the rim 42 from the leftmost portion and a portion that is displaced downward by about 40 ° along the rim 42 from the leftmost portion. Is defined as. Similarly, the right part includes the rightmost part in the neutral state. Here, the right part is sandwiched between a part that is displaced upward by about 40 ° along the rim 42 from the rightmost part and a portion that is displaced downward by about 40 ° along the rim 42 from the rightmost part. Is defined as.

[4 Sensor sheet 74]
As shown in FIG. 6, the capacitance sensor 56 is formed of a flat sensor sheet 74 including a conductive member such as metal. Of the sensor sheet 74, the center line along the longitudinal direction is defined as C1, and the center line parallel to the developed sheet surface and orthogonal to the center line C1 is defined as C2. The sensor sheet 74 is substantially line-symmetric with the center line C2 as the axis of symmetry.

Here, five portions are defined with respect to the sensor sheet 74, which are arranged from one side in the longitudinal direction toward the other side. Specifically, the portion extending from the center line C2 toward the two end portions 76, 76 is referred to as the first portion 80, the portion extending from one end portion 76 toward the center line C2 is referred to as the second portion 82, and the other. The portion extending from the end portion 76 toward the center line C2 is designated as the third portion 84, the portion between the first portion 80 and the second portion 82 is referred to as the fourth portion 86, and the first portion 80 and the third portion 84 are used. The part between and is referred to as the fifth part 88.

The length of each portion in the longitudinal direction can be appropriately set according to the positions and sizes of the spoke non-connecting portion 50 and the spoke connecting portion 48 of the rim 42. In the present embodiment, (length L1 of the first part 80) ≧ (length L2 of the second part 82 + length L3 of the third part 84) ≧ (length L4 of the fourth part 86 + length of the fifth part 88) L5).

The lengths of the first portion 80, the second portion 82, and the third portion 84 in the width direction (the length in the direction orthogonal to the longitudinal direction) are substantially the same. This length corresponds to the first width W1. The lengths of the fourth part 86 and the fifth part 88 in the width direction are substantially the same. This length corresponds to the second width W2. Recesses 90 are formed on both sides of the fourth portion 86 and the fifth portion 88 in the width direction. Therefore, the second width W2 is narrower than the first width W1.

The sensor sheet 74 is attached to the surface of the rim resin 54 so that the center line C1 is along the outer edge portion 72 of the rim resin 54. When the steering wheel 26 is in the neutral state, the first part 80 is located on the upper part of the rim 42 and the upper left and right sides, the second part 82 is located on the lower left part of the rim 42, and the third part 84 is on the right side of the rim 42. Located at the bottom, the fourth site 86 is located on the left side of the rim 42 and the fifth site 88 is located on the right side of the rim 42.

The first part 80, the second part 82, and the third part 84 are located at the spoke non-connection part 50 of the rim 42, the fourth part 86 is located at the left spoke connection part 48L of the rim 42, and the fifth part 88 is the rim. It is located at the right spoke connection portion 48R of 42. The two ends 76, 76 face each other with the lower spoke connecting portion 48B in between. Of the rim 42, the area where the sensor sheet 74 is provided is the sensing area 100, and the area where the sensor sheet 74 is not provided is the dead area 102.

In addition to the sensor sheet 74 forming the capacitance sensor 56, the capacitance sensor 56 may be formed by painting a conductive member on the surface of the rim resin 54.

[5 Operation of steering wheel unit 12]
The operation of the steering wheel unit 12 will be described with reference to FIG. 7. The series of processes described below are repeatedly executed at predetermined time intervals.

In step S1, the overall control unit 36 determines whether or not it is the timing to perform the grip determination (contact determination). The timing for determining the grip is arbitrarily set. For example, the driver does not need to grip the steering wheel 26 when the vehicle 10 travels by automatic steering. At this time, the gripping determination may not be performed. On the other hand, when the vehicle 10 travels by manual steering, the driver needs to grip the steering wheel 26. At this time, the gripping determination may be performed. When it is the timing to perform the grip determination (step S1: YES), the process proceeds to step S2. On the other hand, when it is not the timing to perform the grip determination (step S1: NO), the series of processes is completed and the process waits until the next series of processes is started.

In step S2, the overall control unit 36 determines whether or not it is the timing to return to manual steering. The automatic driving device 14 notifies the driver when it is necessary to return to manual steering during automatic steering, for example, when the vehicle 10 approaches the end position of the automatic driving section. A notification instruction is output to the device 18. At this time, the automatic driving device 14 outputs a return signal indicating that it is the return timing to manual steering to the contact determination device 28. The overall control unit 36 determines that it is the return timing to manual steering when the contact determination device 28 receives the return signal output from the automatic driving device 14, and returns to manual steering when it does not receive it. Judge that it is not the return timing. When it is the timing to return to manual steering (step S2: YES), the process proceeds to step S3. On the other hand, if it is not the timing to return to manual steering (step S2: NO), the process proceeds to step S4.

In step S3, the contact detection unit 38 reads the second threshold value (> first threshold value) from the storage device 34. Then, by comparing with the detection value C of the capacitance sensor 56, it is detected whether or not the driver is gripping the steering wheel 26.

In step S4, the contact detection unit 38 reads the first threshold value (<second threshold value) from the storage device 34. Then, by comparing with the detection value C of the capacitance sensor 56, it is detected whether or not the driver is gripping the steering wheel 26.

When the driver does not grip the steering wheel 26, the notification instruction unit 40 outputs a notification instruction to the notification device 18 to prompt manual steering. Further, when the driver does not grip the steering wheel 26 even after a certain period of time has passed, the contact detection unit 38 outputs non-grasping information indicating that the steering wheel 26 is not gripped to the automatic driving device 14. .. When the automatic driving device 14 inputs the non-grasping information, the automatic driving device 14 decelerates or stops the vehicle 10 on the shoulder of the road.

[Summary of 6 Embodiments]
[Summary of 6.1 Steering Wheel Unit 12]
The steering wheel unit 12 is provided on the steering wheel 26 and includes a capacitance sensor 56 that detects the magnitude of the capacitance associated with the contact of the human body with the steering wheel 26. In the steering wheel unit 12, the capacitance sensor 56 is arranged on the outer peripheral portion 68 of the rim 42 of the steering wheel 26 to form a sensing region 100 for detecting the contact of the human body with the steering wheel 26, and the steering wheel 26 is formed. The left portion (left spoke connection portion 48L) located relatively to the left in the rim 42 when in the neutral state, and the right portion (right spoke connection portion) facing the left portion via the central portion O1 of the rim 42. 48R) and a dead region 102 that does not detect contact with the steering wheel 26 by the human body are formed.

As described above, when the steering wheel 26 is in the neutral state, the left portion (left spoke connection portion 48L) located relatively to the left in the rim 42 and the right portion (right spoke connection) facing the left portion. By forming the insensitive region 102 with the portion 48R), even if the driver's arm or elbow contacts the left and right portions of the rim 42, the capacitance sensor 56 makes contact with the steering wheel 26 by the human body. It does not detect the magnitude of the capacitance associated with it. Therefore, it is possible to prevent erroneous detection that the steering wheel 26 is being gripped.

Further, when the steering wheel 26 is in the neutral state, the dead region 102 is also formed in the lower portion (lower spoke connecting portion 48B) located relatively lower in the rim 42. When the driver holds down the steering wheel 26 with his foot, his foot may come into contact with the lower part of the rim 42. At this time, the capacitance sensor 56 detects the magnitude of the capacitance due to the contact of the human body with the steering wheel 26. Then, even if the driver does not grip the steering wheel 26, a false detection that the steering wheel 26 is gripped is reached. As in the above configuration, if the dead region 102 is also formed in the lower part of the rim 42, which is located relatively lower in the rim 42 when the steering wheel 26 is in the neutral state, the driver's foot is on the rim 42. Even if it comes into contact with the lower part (lower spoke connection portion 48B), the capacitance sensor 56 does not detect the magnitude of the capacitance due to the contact of the human body with the steering wheel 26. Therefore, it is possible to prevent erroneous detection that the steering wheel 26 is being gripped.

The steering wheel unit 12 is provided on the steering wheel 26 and includes a capacitance sensor 56 that detects the capacitance associated with the contact of the human body with the steering wheel 26. In the steering wheel unit 12, the capacitance sensor 56 is arranged on the outer peripheral portion 68 of the rim 42 of the steering wheel 26 to form a sensing region 100 for detecting the contact of the human body with the steering wheel 26, and the steering wheel 26 is formed. A dead region 102 that does not detect contact with the steering wheel 26 by the human body is formed at the connection portion between the spoke 46 and the rim 42 (the lower spoke connection portion 48B such as the right spoke connection portion 48R).

When the driver covers the steering wheel 26 due to poor physical condition or the like, the driver brings his arm or elbow into contact with a portion of the steering wheel 26 having high rigidity, that is, a connection portion between the spoke 46 and the rim 42 (right spoke connection portion 48R, etc.). Tends to deposit weight. If the dead region 102 is formed in a portion where the driver is likely to come into contact with the arm or elbow as in the above configuration, the capacitance sensor 56 will be the steering wheel 26 even if the driver covers the steering wheel 26. It does not detect the magnitude of the capacitance due to contact with the human body. Therefore, it is possible to prevent erroneous detection that the steering wheel 26 is being gripped.

The capacitance sensor 56 has a sheet shape and is attached to the rim 42. According to the above configuration, the sensing region 100 and the dead region 102 can be formed on the rim 42 by a simple structure and work such as attaching a sheet, so that the manufacturing cost is reduced.

In the steering wheel unit 12, the capacitance sensor 56 is arranged on the outer edge 72 of the rim 42 on which the dead region 102 is formed. If the capacitance sensor 56 is arranged on the outer edge 72 of the rim 42 on which the dead region 102 is formed as in the above configuration, the driver correctly grips the rim 42 to grip the steering wheel 26. It is possible to detect that there is. In this way, the gripping state of the steering wheel 26 can be correctly detected.

The steering wheel unit 12 is provided in the vehicle 10 capable of switching between manual steering and automatic steering. The steering wheel unit 12 includes a contact detection unit 38 that detects whether or not a human body is in contact with the steering wheel 26 according to the magnitude of the capacitance detected by the capacitance sensor 56. The contact detection unit 38 determines whether or not the human body is in contact with the steering wheel 26 based on whether or not the magnitude of the capacitance detected by the capacitance sensor 56 is equal to or greater than the first threshold value during manual steering. Detect. When returning from automatic steering to manual steering, the contact detection unit 38 sets a second threshold value larger than the first threshold value, and whether the magnitude of the capacitance detected by the capacitance sensor 56 is equal to or greater than the second threshold value. Based on whether or not the steering wheel 26 is in contact with the human body, it is detected. In the vehicle 10 capable of switching between manual steering and automatic steering, the driver is required to grip the steering wheel 26 when returning from automatic steering to manual steering. As in the above configuration, when returning from automatic steering to manual steering, it is detected whether or not the human body is in contact with the steering wheel 26 by comparing with a second threshold value larger than the first threshold value set at the time of manual steering. If set to, the recognition accuracy of gripping is improved.

[6.2 Summary of Steering Wheel 26]
The steering wheel 26 includes a rim 42 and spokes 46. The rim 42 includes a plurality of spoke connecting portions 48 connected to the spokes 46, and spoke non-connecting portions 50 that are interposed between the spoke connecting portions 48 adjacent to each other and are not connected to the spokes 46. A capacitance sensor 56 is provided on the outer peripheral portion 68 of the rim 42 along the circumferential direction of the cross section of the rim 42. The second width W2 in the cross-sectional circumferential direction of the capacitance sensor 56 provided in the spoke connecting portion 48 is narrower than the first width W1 in the cross-sectional circumferential direction of the capacitance sensor 56 provided in the spoke non-connecting portion 50.

As in the above configuration, the second width W2 of the capacitance sensor 56 provided at the spoke connection portion 48 where the driver is likely to come into contact with the arm or elbow is the first of the capacitance sensor 56 provided at another portion. If the width is narrower than W1, even if the driver covers the steering wheel 26, the capacitance sensor 56 does not detect the capacitance due to the contact of the human body with the steering wheel 26. Therefore, it is possible to prevent erroneous detection that the steering wheel 26 is being gripped.

[Summary of 6.3 sensor sheet 74]
The sensor sheet 74 is formed from a first portion 80 extending from the center in the longitudinal direction toward the two ends 76 and 76, a second portion 82 extending from one end 76 toward the center, and the other end 76. It consists of a third site 84 extending toward the center, a fourth site 86 between the first site 80 and the second site 82, and a fifth site 88 between the first site 80 and the third site 84. The first part 80, the second part 82, and the third part 84 have a first width W1 in the width direction of the sheet, and the fourth part 86 and the fifth part 88 have a second width W2 in the width direction of the sheet. .. The second width W2 is narrower than the first width W1.

According to the above configuration, the sensing region 100 and the dead region 102 can be formed on the rim 42 by a simple structure and work such as attaching the sensor sheet 74, so that the manufacturing cost is reduced.

10 ... Vehicle 12 ... Steering wheel unit 26 ... Steering wheel 42 ... Rim 46 ... Spoke 48 ... Spoke connection 50 ... Spoke non-connection 56 ... Capacitance sensor 68 ... Outer circumference 74 ... Sensor sheet 76 ... End 80 ... No. 1 site 82 ... 2nd site 84 ... 3rd site 86 ... 4th site 88 ... 5th site 100 ... Sensing area 102 ... Insensitive area

Claims (7)

A steering wheel with rims and spokes
The rim comprises a plurality of spoke connecting portions connected to the spokes, and spoke non-connecting portions interposed between the spoke connecting portions adjacent to each other and not connected to the spokes.
A capacitance sensor is provided on the outer peripheral portion of the rim along the circumferential direction of the cross section of the rim.
A steering wheel characterized in that the width of the capacitance sensor provided at the spoke connection portion in the cross-sectional circumferential direction is narrower than the width of the capacitance sensor provided at the spoke non-connection portion in the cross-sectional circumferential direction. In the steering wheel according to claim 1,
The lower part of the rim, which is located relatively lower in the rim when the steering wheel is in the neutral state, is also static along the circumferential direction of the cross section of the rim from the spoke connecting portion toward the spoke non-connecting portion. A steering wheel characterized in that a portion narrower than the width in the circumferential direction of the cross section of the capacitance sensor extends. In the steering wheel according to claim 1 or 2.
A steering wheel characterized in that the capacitance sensor has a sheet shape and is attached to the rim. In the steering wheel according to any one of claims 1 to 3.
A steering wheel characterized in that the capacitance sensor is arranged at an outer edge of a rim on which a dead region is formed. In the steering wheel according to any one of claims 1 to 4.
The vehicle can be switched between manual steering and automatic steering,
Further provided with a contact detection unit that detects whether or not a human body is in contact with the steering wheel according to the magnitude of the capacitance detected by the capacitance sensor.
The contact detection unit
At the time of manual steering, it is detected whether or not the human body is in contact with the steering wheel based on whether or not the magnitude of the capacitance detected by the capacitance sensor is equal to or greater than the first threshold value.
When returning from the automatic steering to the manual steering, a second threshold value larger than the first threshold value is set.
A steering wheel characterized in that it detects whether or not a human body is in contact with the steering wheel based on whether or not the magnitude of the capacitance detected by the capacitance sensor is equal to or greater than a second threshold value. A sensor sheet made of a conductive member and attached to the rim of a steering wheel to form a capacitance sensor.
A first part extending from the longitudinal center of the sheet towards the two ends,
A second part extending from one end toward the center,
A third part extending from the other end toward the center,
The fourth part between the first part and the second part,
It consists of a fifth part between the first part and the third part.
The first portion, the second portion, and the third portion have a first width in the width direction of the sheet.
The fourth portion and the fifth portion have a second width in the width direction of the sheet.
A sensor sheet characterized in that the second width is narrower than the first width. The sensor sheet according to claim 6.
When the sensor sheet is placed on the steering wheel,
The sensor sheet is characterized in that the fourth portion and the fifth portion are arranged at a connection portion between the spokes of the steering wheel and the rim.

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