OA18076A

OA18076A - Sub headlight unit and sub headlight system for use in vehicle that leans into turns, and vehicle that leans into turns, and method for controlling light emission of a sub headlight unit.

Info

Publication number: OA18076A
Application number: OA1201600433
Authority: OA
Inventors: Takeshi Ikeda; Yasuhiko Kino; Takehiro Inoue; Makoto Kosugi
Original assignee: Yamaha Hatsudoki Kabushiki Kaisha
Priority date: 2012-03-19
Filing date: 2016-11-15
Publication date: 2018-04-06

Abstract

A sub headlight unit for use in a vehicle that leans into turns includes a sub headlight light source that illuminates an area ahead and outward of the vehicle with respect to a width direction of the vehicle. The sub headlight light source is configured to, when the vehicle is in an upright state, produce an illumination range including a space above a horizontal plane. The sub headlight light source is turned on in accordance with a lean angle of the vehicle. At a time of parking or stopping or at a time of running straight ahead, the sub headlight light source is turned on or caused to flash with the amount of light per unit time being reduced as compared with the amount of light per unit time emitted when the sub headlight light source is turned on in accordance with the lean angle of the vehicle.

Description

SUB HEADLIGHT UNIT AND SUB HEADLIGHT SYSTEM FOR USE IN VEHICLE THAT LEANS INTO TURNS, AND VEHICLE THAT LEANS INTO TURNS, AND METHOD FOR CONTROLLING LIGHT EMISSION OF A SUB HEADLIGHT UNIT [0001]

The présent invention relates to a sub headlight unit and a sub headlight System for use in a vehicle that leans into turns, and to a vehicle that leans into turns, and to a method for controlling light émission of a sub headlight light source.

[0002]

In general, in a vehicle that leans into turns (such as saddle-ride type vehicles including motorcycles, three-wheeled motor vehicles, snowmobiles, and ATVs (ail terrain vehicles)), when the vehicle corners or turns at an intersection, a rider opérâtes a handlebar and additionally shifts his/her own weight in order to counteract centrifugal force acting on a vehicle body. Thereby, the vehicle turns with an attitude (hereinafter, also referred to as “lean attitude”) leaning to the inner side of a curve. On the other hand, in a vehicle that does not lean into turns, for example, in an automobile, when the vehicle corners or turns at an intersection, a rider opérâtes a steering wheel and the vehicle turns with centrifugal force acting on a vehicle body thereof. Therefore, in the vehicle that does not lean into turns, the vehicle body leans to the outer side of a curve due to the centrifugal force.

[0003]

In the vehicle that leans into turns, the turning is made with an active use of the weight shifting of the rider himself/herself. Therefore, the vehicle body largely leans. In the vehicle that does not lean into turns, the vehicle body leans to the outer side of the curve due to the centrifugal force. The degree of this leaning varies depending on the running speed of the vehicle and the magnitude (radius) of the curve, and this leaning of the vehicle body is not utilized for the turning. In the vehicle that does not lean into turns, it is préférable that the amount of leaning to the outer side of the curve due to the centrifugal force is small.

[0004]

Thus, at a time of cornering or turning at an intersection, the vehicle that leans into turns causes the vehicle body to lean to the inner side of the curve with a relatively large amount of leaning, while the vehicle that does not lean into turns causes the vehicle body to lean to the outer side of the curve with a relatively small amount of leaning.

[0005]

Normally, a vehicle is provided with a plurality of lights irrespective of whether or not the vehicle leans into turns. The lights include a light intended mainly to ensure a field of view of a rider of the vehicle and a light intended mainly to enable a surrounding vehicle or the like to recognize the presence of the own vehicle. A headlight is the light intended mainly to ensure the field of view of the rider of the vehicle, and in general, is configured to switch between a high beam (running headlight) and a low beam (passing headlight).

[0006]

The high beam, which emits light in a horizontal (upward) direction, ensures a field of view at a long distance. Generally, in order to avoid dazzling a rider of a surrounding vehicle, the high beam is used in a situation where there is no vehicle or the like existing ahead at night. The low beam, which emits light in a downward direction, is used even in a situation where there is a vehicle or the like existing ahead. Therefore, in a normal case, a vehicle often runs with the low beam turned on.

[0007]

When the vehicle that leans into turns is running on a straight road, an illumination range of a headlight light source (low beam) spreads evenly to the left and right in an area ahead in an advancing direction and below a horizontal line of the headlight light source. When the vehicle that leans into turns is running on a road curving to the left, the vehicle runs 15 with the vehicle body inclined to the left. Accordingly, the illumination range of the headlight light source spreads downward to the left. As a resuit, a nearer position on a running lane is illuminated. Thus, the illumination range in an area inside the curve and ahead in the advancing direction is reduced.

[0008]

Therefore, a vehicle has been proposed in which, in addition to a main headlight that illuminâtes an area ahead of the vehicle, a pair of right and left sub headlights that are turned on depending on the magnitude of a lean angle (angle of inclination of a vehicle body to the inner side of a curve relative to an upright state thereof) are provided as the headlight (JP4806550). When the vehicle body is in the upright state, illumination ranges of the pair of right and left sub 25 headlights are located above a cut-off line (which means a boundary line that defines the upper edge of the illumination range) of the main headlight, but the sub headlights are not turned on when the vehicle body is in the upright state. That is, in the vehicle disclosed in JP4806550, when the lean angle of the vehicle body increases and reaches a predetermined value, the sub headlights, which are arranged at the inner side of a curve, are turned on, while when the lean 30 angle of the vehicle body decreases and faits below the predetermined value, the sub headlights are turned off.

[0009]

In this manner, when the lean angle is large, the sub headlights shown in JP4806550 ensure a wide illumination range in an area inside a curve and ahead in the advancing direction, 35 thus improving the visibility ahead in a path at a time of running in a curve. On the other hand, as described above, the sub headlights are directed upward, and hâve a relatively high brightness for improving the visibility ahead in a path. Therefore, when the lean angle is small, the sub headlights are turned off, to prevent dazzling of, for example, a rider of a surrounding vehicle.

[0010]

Thus, the sub headlight shown in JP4806550 is a device useful for the vehicle that leans into turns, because the sub headlight has a function for adjusting a brightness level in accordance with the lean angle, to thereby ensure a wide illumination range in an inside area ahead in an advancing direction with suppression of glare.

[0011]

Meanwhile, in the field of vehicles, from the viewpoint of the running performance and 10 energy efficiency, it is generally desired that a vehicle body is a lightweight and its size is not more than required. Particularly, in the vehicle that leans into turns, downsizing of a vehicle body is quite strongly demanded for the reason that, for example, the attitude of a vehicle body is controlled by the weight shifting of a rider. Therefore, even the useful device as shown in JP4806550 is not easily allowed to be mounted on the vehicle body. Instead, it is desired that 15 one device serves a plurality of functions.

[0012]

It is the object of the présent invention to provide a sub headlight unit and a sub headlight System suitable for a vehicle that leans into turns and also to provide a vehicle that leans into turns, and also to provide a method for controlling light émission of a sub headlight 20 light source in which characteristics of a sub headlight are leveraged to thereby achieve different functions with suppression of a size increase.

[0013]

According to the présent invention said object is solved by a sub headlight unit for use in a vehicle that leans into turns having the features of independent claim 1. Moreover, said 25 object is solved by a sub headlight System for use in a vehicle that leans into turns having the features of claim 6. Moreover, said object is solved by a vehicle that leans into turns according to claim 9. Moreover, said object is solved by a method for controlling light émission of a sub headlight light source having the features of independent claim 10. Preferred embodiments are laid down in the dépendent daims.

[0014]

To solve the problems described above, the présent teaching adopts the following configurations.

(1) A sub headlight unit for use in a vehicle that leans into turns, the sub headlight unit including a sub headlight light source that illuminâtes an area 35 ahead and outward of the vehicle with respect to a width direction of the vehicle, wherein the sub headlight light source is configured to, when the vehicle is in an upright state, produce an illumination range including a space above a horizontal plane, and the sub headlight light source is turned on in accordance with a lean angle of the vehicle and, at a time of parking or stopping or at a time of running straight ahead, the sub headlight light source is turned on or caused to flash with the amount of light per unit time being reduced as compared with the amount of light per unit time emitted when the sub headlight light source is turned on in accordance with the lean angle of the vehicle.

[0015]

The sub headlight light source is a light intended mainly to ensure a field of view of a rider of the vehicle. Therefore, the sub headlight light source is installed in such a manner that it produces an illumination range including a space above the horizontal plane when the vehicle is in the upright state. Additionally, the brightness of the sub headlight light source is relatively high. Accordingly, for prévention of glare, in the conventional configuration, the sub headlight light source is turned on when the lean angle of the vehicle is large.

However, in a configuration of (1), at a time of parking or stopping or at a time of running straight ahead, the sub headlight light source is turned on or caused to flash with the amount of light per unit time being reduced. Thereby, the sub headlight light source is used as a light intended to enable a surrounding vehicle or the like to recognize the presence of the own vehicle with prévention of glare. For example, causing the sub headlight light source to flash when the vehicle is stopped can achieve an answerback function. Turning on the sub headlight light source in a dimmed state when the vehicle is running straight ahead can achieve a function as a position light. Since the sub headlight light source is installed in such a manner that it produces an illumination range including a space above the horizontal plane when the vehicle is in the upright state, an excellent conspicuity is obtained when seen from the surroundings. Accordingly, the sub headlight light source is able to serve a plurality of functions, which can suppress a size increase of the device as a whole.

[0016]

According to the présent teaching, the amount of light per unit time emitted from the sub headlight light source at a time of parking or stopping or at a time of running straight ahead is smaller than the amount of light per unit time emitted from the sub headlight light source when the sub headlight light source is turned on in accordance with the lean angle of the vehicle. The unit time is not limited to one second, but can be set to any value. As for the magnitude relationship between these amounts of light, for example, in a case where the sub headlight light source is turned on in a full-light state in accordance with the lean angle of the vehicle while the sub headlight light source is turned on in a dimmed state at a time of parking or stopping or at a time of running straight ahead, the magnitude relationship between the amounts of light is obvious even without précisé identification of the amounts of light. Also, in a case where the sub headlight light source is turned on in the full-light state in accordance with the lean angle of the vehicle while the sub headlight light source is caused to flash with full light at a time of parking or stopping or at a time of running straight ahead, the magnitude relationship between the amounts of light is obvious even without précisé identification of the amounts of light. When, in this manner, the magnitude relationship between the amounts of light can be identified from a manner of turn-on of the sub headlight light source, it is not always necessary to actually measure the amount of light.

[0017]

As described above, the unit time can be set to any value. However, for example, in a case where one of the amounts of light is the amount of light per unit time emitted when the sub headlight light source flashes, the unit time is set equal to or longer than a period of the flashing, for facilitating the comparison between the amounts of light.

[0018] (2) The sub headlight unit according to (1), wherein an illumination range of the sub headlight light source produced when the sub headlight light source is tumed on or caused to flash with the amount of light per unit time being reduced is located higher than an illumination range of the sub headlight light source produced when the sub headlight light source is tumed on in accordance with the lean angle of the vehicle.

[0019]

A configuration of (2) can improve the conspicuity in a case where the sub headlight light source is used as a light (for example, an answerback or position light) intended to enable a surrounding vehicle or the like to recognize the presence of the own vehicle.

[0020] (3) The sub headlight unit according to (1) or (2), wherein an optical axis of the sub headlight light source occurring when the sub headlight light source is tumed on or caused to flash with the amount of light per unit time being reduced is directed upward relative to an optical axis of the sub headlight light source occurring when the sub headlight light source is turned on in accordance with the lean angle of the vehicle.

[0021]

A configuration of (3) can improve the conspicuity in a case where the sub headlight light source is used as a light intended to enable a surrounding vehicle or the like to recognize the presence of the own vehicle.

[0022] (4) The vehicle according to any one of (1) to (3), wherein the sub headlight light source is turned on or caused to flash with the amount of light per unit time being reduced, under a state where an optical axis of the sub headlight light source is directed at or above a horizontal plane.

[0023]

A configuration of (4) can improve the conspicuity in a case where the sub headlight light source is used as a light intended to enable a surrounding vehicle or the like to recognize the presence of the own vehicle.

[0024] (5) The vehicle according to any one of (1) to (4), wherein when the sub headlight light source is tumed on in accordance with the lean angle of the vehicle, a cut-off line of the sub headlight light source is located at or below a horizontal line of the sub headlight light source, while when the sub headlight light source is tumed on or caused to flash with the amount of light per unit time being reduced, the cut-off line of the sub headlight light source is wholly or partially located in a space above the horizontal line of the sub headlight light source.

[0025]

A configuration of (5) can improve the conspicuity in a case where the sub headlight light source is used as a light intended to enable a surrounding vehicle or the like to recognize the presence of the own vehicle.

[0026] (6) A sub headlight System for use in a vehicle that leans into turns, the sub headlight System including:

the sub headlight unit according to any one of (1) to (5);

a control part that controls light émission of the sub headlight light source; and a détection part that detects a variable used for obtaining the lean angle of the vehicle, wherein the control part turns on the sub headlight light source in accordance with the lean angle of the vehicle and, at a time of parking or stopping or at a time of running straight ahead, the control part causes the sub headlight light source to be turned on or flash with the amount of light per unit time being reduced as compared with the amount of light per unit time emitted when the sub headlight light source is turned on in accordance with the lean angle of the vehicle.

[0027]

In a configuration of (6), the sub headlight light source is turned on in accordance with the lean angle and thereby functions as a light intended mainly to ensure a field of view of a rider of the vehicle, while, at a time of parking or stopping or at a time of running straight ahead, the sub headlight light source is turned on or caused to flash with the amount of light per unit time being reduced and thereby functions as a light intended to enable a surrounding vehicle or the like to recognize the presence of the own vehicle. Since the sub headlight light source is installed in such a manner that it produces an illumination range including a space above the horizontal plane when the vehicle is in the upright state, an excellent conspicuity is obtained when seen from the surroundings. Accordingly, the sub headlight light source is able to serve a plurality of functions. As a resuit, an AFS (Adaptive Front-Lighting System) that can suppress a size increase of the device as a whole is achieved.

[0028] (7) The sub headlight System according to (6), the sub headlight System including a communication part that communicates with a portable communication device that is portable for a rider, wherein the control part turns on the sub headlight light source in accordance with the lean angle of the vehicle and, in a case where communication between the communication part and 10 the portable communication device satisfies a predetermined condition at a time of parking or stopping, the control part causes the sub headlight light source to be tumed on or flash with the amount of light per unit time being reduced as compared with the amount of light per unit time emitted when the sub headlight light source is tumed on in accordance with the lean angle of the vehicle.

[0029]

In a configuration of (7), the sub headlight light source has a function of answerback. Since the amount of light per unit time is reduced, dazzling of surroundings can be prevented. Moreover, since the illumination range includes a space above the horizontal plane, an excellent conspicuity is obtained when seen from the surroundings. Accordingly, the sub 20 headlight light source is tumed on in accordance with the lean angle, and on the other hand, exerts an excellent answerback function at a time of parking or stopping.

[0030] (8) The sub headlight System according to (6) or (7), wherein the control part turns on the sub headlight light source in accordance with the lean 25 angle of the vehicle and, at a time of running straight ahead, the control part turns on the sub headlight light source with the amount of light per unit time being reduced.

[0031]

In a configuration of (8), the sub headlight light source has a function as a position light. Since the amount of light per unit time is reduced, dazzling of surroundings can be 30 prevented. Moreover, since the illumination range includes a space above the horizontal plane, an excellent conspicuity is obtained when seen from the surroundings. Accordingly, the sub headlight light source is tumed on in accordance with the lean angle, and on the other hand, exerts an excellent function as a position light at a time of running straight ahead.

[0032] (9) A vehicle that leans into turns, the vehicle including the sub headlight System according to any one of (6) to (8).

[0033]

In a configuration of (9), the sub headlight light source is turned on in accordance with the lean angle and thereby functions as a light intended mainly to ensure a field of view of a rider of the vehicle, while, at a time of parking or stopping or at a time of running straight ahead, the sub headlight light source is turned on or caused to flash with the amount of light per unit 5 time being reduced and thereby functions as a light intended to enable a surrounding vehicle or the like to recognize the presence of the own vehicle. Since the sub headlight light source is installed in such a manner that it produces an illumination range including a space above the horizontal plane when the vehicle is in the upright state, an excellent conspicuity is obtained when seen from the surroundings. Accordingly, the sub headlight light source is able to serve 10 a plurality of functions, which can suppress a size increase of the device as a whole.

[0034]

Here, according to the présent teaching, the optical axis is a straight line that passes through a light source and the center of a maximum illuminance portion of emitted light. The center of the maximum illuminance portion of the emitted light can be identified by emitting light 15 from a light source to a screen that is placed ahead of the light source. This screen illuminance test can be implemented by a method specified in JIS D1619. Also, the cut-off line and the illumination range having the predetermined illuminance can be identified based on a resuit (such as an isolux distribution map) of the screen illuminance test mentioned above. The cut-off line and the illumination range having the predetermined illuminance in a plan view 20 can be identified based on a road-surface light distribution that is obtained by converting the resuit of the screen illuminance test mentioned above into the road-surface light distribution. The conversion into the road-surface light distribution can be implemented by a conventionally known method. To be spécifie, through commonly-used drawing and géométrie calculation, conversion from a screen illuminance value into a road-surface illuminance value can be 25 performed. In such a case, the following expression (I) is usable. In the following expression (I), D represents a light source, E represents a point on a road surface, and F represents a point of intersection at which the screen placed between D and E intersects with a straight line connecting D to E.

Road-surface illuminance (Lx) = Screen llluminance (Lx) x [(Distance between D and 30 F (m)) / (Distance between D and E (m))]² ... (I) [0035]

These and other objects, features, aspects and advantages of the présent invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the accompanying drawings, discloses some embodiments of the 35 présent teaching.

[EFFECTS OFTHE INVENTION] [0036]

According to the présent teaching, characteristics of a sub headlight light source are leveraged, and thereby different functions are achieved in the sub headlight light source with suppression of a size increase.

[BRIEF DESCRIPTION OFTHE DRAWINGS] [0037] [FIG. 1] A front elevational view schematically showing a motorcycle according to an embodiment of the présent teaching.

[FIG. 2] A block diagram showing a basic configuration concerning sub headlight light sources of the motorcycle shown in FIG. 1.

[FIG. 3] A diagram schematically showing a screen light distribution of the motorcycle of FIG. 1 when the motorcycle is in an inclined state.

[FIG. 4] A diagram schematically showing a screen light distribution of the motorcycle of FIG. 1 when the motorcycle is in an upright state.

[FIG. 5] (a) to (c) are diagrams showing an example of a lighting pattern of the sub headlight light sources of the motorcycle of FIG. 1; and (d) to (f) are diagrams showing another example of the lighting pattern.

[EMBODIMENTS FOR CARRYING OUT THE INVENTION] [0038]

FIG. 1 is a front elevational view schematically showing a motorcycle 10 according to an embodiment of the présent teaching.

The motorcycle 10 is an example of a vehicle that leans into turns according to the présent teaching. According to the présent teaching, no particular limitation is put on the vehicle that leans into turns. For example, saddle-ride type vehicles including motorcycles, three-wheeled motor vehicles, snowmobiles, and ATVs (ail terrain vehicles) may be mentioned. In the following description, the terms “front” and “back” are terms with respect to an advancing direction of the vehicle, the terms “up” and “down” are terms with respect to the vertical direction of the vehicle, and the terms “right” and “left” are terms with respect to a rider.

[0039]

The motorcycle 10 includes a handlebar 12. An operation switch 15 is provided in a left portion of the handlebar 12 with respect to a width direction of the vehicle. The operation switch 15 includes a beam switch 15B and a flasher switch 15F (see FIG. 2). A steering shaft (not shown) is fixed to a center portion of the handlebar 12 with respect to the width direction of the vehicle. The steering shaft extends downward through a headpipe (not shown). A frontfork 17 is provided at a lower end of the steering shaft. A front wheel 16 is rotatably

ΙΟ supported at the lower end of the frontfork 17. The headpipe is a member constituting a vehicle body frame. According to the présent teaching, no particular limitation is put on the vehicle body frame, and a conventionally known configuration is adoptable.

[0040]

A front cover 18 covers a front part of the headpipe having the steering shaft passing therethrough. On a front surface of the front cover 18, a main headlight 11 is provided in a center portion with respect to the width direction of the vehicle. The main headlight 11 includes a high beam light source 11H (running headlight) and a low beam light source 11L (passing headlight). The high beam light source 11H illuminâtes an area ahead of the motorcycle 10 at 10 a height equal to or above a horizontal plane of the main headlight 11. The low beam light source 11L illuminâtes an area ahead of the motorcycle 10 at a height below the horizontal plane of the main headlight 11.

[0041]

The high beam light source 11H and the low beam light source 11L are configured such that only one of them is turned on at one time. The rider opérâtes the beam switch 15B (see FIG. 2), and thereby turn-on of the high beam light source 11H and turn-on of the low beam light source 11L are switched.

[0042]

The motorcycle 10 includes a sub headlight 13. The sub headlight 13 is composed 20 of two sub headlight units 13L and 13R of variable light distribution type. Each of the sub headlight units 13L and 13R is provided at each side with respect to the width direction of the vehicle. The sub headlight unit 13L includes a plurality of sub headlight light sources 13La, 13Lb, and 13Lc. The sub headlight light sources 13La, 13Lb, and 13Lc are arranged in this order from the center toward the upper left with respect to the width direction of the vehicle. 25 Illumination ranges of the sub headlight light sources 13La, 13Lb, and 13Lc are arranged in this order from the center toward the upper left with respect to the width direction of the vehicle. The illumination ranges of the sub headlight light sources 13La, 13Lb, and 13Lc overlap one another (see FIGS. 3 and 4). The sub headlight unit 13R includes a plurality of sub headlight light sources 13Ra, 13Rb, and 13Rc. The sub headlight light sources 13Ra, 13Rb, and 13Rc 30 are arranged in this order from the center toward the upper right with respect to the width direction of the vehicle. Illumination ranges of the sub headlight light sources 13Ra, 13Rb, and 13Rc are arranged in this order from the center toward the upper right with respect to the width direction of the vehicle. The illumination ranges of the sub headlight light sources 13Ra, 13Rb, and 13Rc overlap one another (see FIGS. 3 and 4). Optical axes of the sub headlight light 35 sources 13La to 13Lc, 13Ra to 13Rc are fixed, and not moved in accordance with the lean angle. A reflector (not shown) of the sub headlight light source is also fixed, and not moved in accordance with the lean angle. In this embodiment, no particular limitation is put on the sub headlight light source. For example, an LED is adoptable. A mono-focus type light source is also adoptable as the sub headlight light source. As for how the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc are arranged in the motorcycle 10, the above-described arrangement manner is merely an illustrative example of the présent teaching. The présent teaching is not limited to this example.

[0043]

Flashers 14L and 14R, serving as direction indicators, are provided at both sides of the motorcycle 10 with respect to the width direction of the vehicle. The flashers 14L and 14R are configured such that only one of them flashes at one time. The rider opérâtes the flasher switch 15F (see FIG. 2), and thereby flashing/turn-off of the flashers 14L and 14R is switched.

[0044]

The plurality of sub headlight light sources 13La, 13Lb, and 13Lc, which are positioned at the left side in the motorcycle 10 with respect to the width direction of the vehicle, are arranged between the main headlight 11 and the flasher 14L. The plurality of sub headlight light sources 13Ra, 13Rb, and 13Rc, which are positioned at the right side in the motorcycle 10, are arranged between the main headlight 11 and the flasher 14R. According to the présent teaching, no particular limitation is put on the positional relationship between the sub headlight light source and the flasher. For example, it may be acceptable that the sub headlight light source is provided outside the flasher with respect to the width direction of the vehicle.

[0045]

The plurality of sub headlight light sources 13La, 13Lb, and 13Lc are provided above the main headlight 11 and the flasher 14L. The plurality of sub headlight light sources 13Ra, 13Rb, and 13Rc are provided above the main headlight 11 and the flasher 14R.

[0046]

The plurality of sub headlight light sources 13La to 13Lc, which are provided to the left with respect to the width direction of the vehicle, illuminate an area ahead of and left-lateral to the motorcycle 10. The plurality of sub headlight light sources 13Ra to 13Rc, which are provided to the right with respect to the width direction of the vehicle, illuminate an area ahead of and right-lateral to the motorcycle 10.

[0047]

FIG. 2 is a block diagram showing a basic configuration concerning the sub headlight light sources 13Lato 13Lc, 13Rato 13Rc of the motorcycle 10 shown in FIG. 1.

The operation switch 15 includes the beam switch 15B and the flasher switch 15F. The beam switch 15B is connected to the high beam light source 11H and the low beam light source 11L included in the main headlight 11. When the rider opérâtes the beam switch 15B, turn-on/turn-off of the high beam light source 11H and the low beam light source 11L is switched in accordance with the operation performed on the beam switch 15B.

[0048]

The flasher switch 15F is connected to the flashers 14L and 14R. When the rider opérâtes the flasher switch 15F, one of the flashers 14L and 14R is caused to flash in accordance with the operation performed on the flasher switch 15F.

[0049]

In the motorcycle 10, an attitude détection sensor 22 and a vehicle speed sensor 23 are provided. In this embodiment, the attitude détection sensor 22 is a gyro sensor that detects the angular velocity about an axis in the front-back direction of the motorcycle 10. The attitude détection sensor 22 supplies, to a controller 20, a signal indicating the detected angular velocity (roll rate) about the axis in the front-back direction. The vehicle speed sensor 23 detects the vehicle speed, and supplies, to the controller 20, a signal indicating the detected vehicle speed. Each time a predetermined timing cornes during running, the controller 20 calculâtes the lean angle of the motorcycle 10 based on the angular velocity about the axis in the front-back direction and the vehicle speed.

[0050]

In this embodiment, the roll rate is integrated overtime, and the vehicle speed is used as correction information, thereby calculating the lean angle. However, according to the présent teaching, a method for calculating the lean angle is not limited to this example. In the calculation of the lean angle, the vehicle speed is not an essential variable. For calculating the lean angle, a conventionally known method is adoptable. For example, the calculation may be performed based on a static equilibrium équation by using the yaw rate (angular velocity about an axis in the vertical direction) and the vehicle speed. The correction information is not limited to the vehicle speed. For example, it may be acceptable to provide a plurality of gyro sensors and G sensors and use values obtained from these sensors and the vehicle speed as the correction information. Instead of the vehicle speed, GPS position information and/or geomagnetic information may be used as the correction information. No particular limitation is put on sensors (détection part) for detecting variables that are available for obtaining the lean angle. An appropriate sensor may be provided in accordance with variables available for the calculation.

[0051]

The controller 20 includes a memory (not shown). The memory stores, in the form of data, a plurality of reference values to be compared with the lean angle. In this embodiment, the memory stores three reference values (a first reference value, a second reference value, and a third reference value). The first reference value, the second reference value, and the third reference value satisfy the relationship of first reference value < second reference value < third reference value.

The first reference value is associated with the sub headlight light sources 13La and 13Ra.

The second reference value is associated with the sub headlight light sources 13Lb and 13Rb.

The third reference value is associated with the sub headlight light sources 13Lc and 13Rc.

[0052]

In the motorcycle 10, at a time of parking (when an engine is stopped), the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc are turned off, and at a time of stopping and at a time of running straight ahead, ail or part of the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc are turned on in a dimmed state. The number and the positions of the sub headlight light sources to be turned on are not particularly limited.

[0053]

No particular limitation is put on a method for dimming the sub headlight light source. For example, it may be conceivable to reduce a current to be supplied to the sub headlight light source, or to reduce a voltage to be supplied to the sub headlight light source. For adjusting light of a sub headlight light source such as an LED by means of a puise width modulation control (PWM control), reducing the duty cycle can dim the sub headlight light source.

[0054]

Alternatively, a single sub headlight light source may include a plurality of light sources having different brightnesses. In this case, the dimming of the sub headlight light source can be implemented by switching which of the light sources is turned on. For example, in a case where a single sub headlight light source includes two light sources having different brightnesses, switching the turn-on light source from light source having a higher brightness to the light source having a lower brightness enables the sub headlight light source to light up in a dimmed state.

[0055]

Furthermore, a single sub headlight light source may include a plurality of light sources. In this case, the dimming of the sub headlight light source can be implemented by changing the number or combination of light sources that are turned on. The brightnesses of the plurality of light sources may be either different or the same. For example, in a case where a single sub headlight light source includes a plurality of light sources (for example, four light sources) having the same brightness, turning on ail the plurality of light sources enables the sub headlight light source to light up in a full-light state while turning on part of the plurality of light sources enables the sub headlight light source to light up in a dimmed state.

[0056]

In the course of a graduai increase in the lean angle along with inclination of the

I4 motorcycle 10 to the left, when the lean angle reaches the first reference value, the sub headlight light source 13La is turned on in the full-light state, and when the lean angle reaches the second reference value, the sub headlight light source 13Lb is turned on in the full-light state, and when the lean angle reaches the third reference value, the sub headlight light source 5 13Lc is turned on in the full-light state. Thus, along with an increase in the lean angle, the sub headlight light sources 13La, 13Lb, and 13Lc sequentially change from the dimmed state into the full-light state. On the other hand, when the lean angle decreases, the sub headlight light sources 13Lc, 13Lb, and 13La sequentially change from the full-light state into the dimmed state. The same applies to a case where the motorcycle 10 is inclined to the right.

[0057]

It may be also acceptable that, while the sub headlight light sources 13La, 13Lb, and 13Lc sequentially change from the dimmed state into the full-light state along with an increase in the lean angle, the sub headlight light sources 13Rc, 13Rb, and 13Ra sequentially change from the dimmed state into a turn-off state.

To be spécifie, it may be acceptable that, when the vehicle is inclined to one side (for example, to the left) with respect to the width direction of the vehicle so that the lean angle increases, the plurality of sub headlight light sources (13La to 13Lc) that illuminate this one side increase their brightnesses sequentially in ascending order from the sub headlight light source (13La) having an illumination range whose upper end edge is located lowerto the sub headlight 20 light source (13Lc) having an illumination range whose upper end edge is located upper, while the plurality of sub headlight light sources (13Rc to 13Ra) that illuminate the other side (right side) of the vehicle with respect to the width direction of the vehicle decrease their brightnesses sequentially in descending order from the sub headlight light source (13Rc) having an illumination range whose upper end edge is located upper to the sub headlight light source 25 (13Ra) having an illumination range whose upper end edge is located lower.

[0058]

An answerback main unit 21 is connected to the controller 20. The answerback main unit 21 receives a signal radio wave from a remote control key 25 serving as a transmitter. The remote control key 25 is portable for the rider. When communication with the remote control 30 key 25 satisfies a predetermined condition, the answerback main unit 21 transmits to the controller 20 a request signal for changing the brightnesses of the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc. The predetermined condition is not particularly limited, and examples thereof include that the answerback main unit 21 receives a signal from the remote control key 25 when the vehicle is parked (when the engine is stopped) and that an answer 35 signal in response to an inquiry signal of the answerback main unit 21 is not received from the remote control key 25 when the vehicle is stopped (when the engine is running).

[0059] «

The controller 20 receives the request signal from the answerback main unit 21. Then, the controller 20 performs a control to change the brightnesses of the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc, and performs an answerback operation. In this embodiment, in the answerback operation, the sub headlight light sources 13La to 13Lc, 13Ra . 5 to 13Rc are turned on in a predetermined pattern. The answerback operation will be detailed with reference to FIG. 5.

[0060]

In this embodiment, the beam switch 15B and the flasher switch 15F are connected to the controller 20, and signais supplied from the beam switch 15B and the flasher switch 15F are 10 inputted to the controller 20.

According to the présent teaching, the controller 20 is allowed to control the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc by using the signais supplied from the beam switch 15B and the flasher switch 15F.

In such a case, no particular limitation is put on a manner of using the signais supplied 15 from the beam switch 15B and the flasher switch 15F.

For example, it may be conceivable that, when a signal for turning on the high beam light source 11H is received from the beam switch 15B, the controller 20 does not control the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc in accordance with the lean angle. In this case, when the high beam light source 11H is turned on, the controller 20 may turn off the 20 sub headlight light sources 13La to 13Lc, 13Ra to 13Rc, or may turn on any of the sub headlight light sources 13Lato 13Lc, 13Rato 13Rc.

It may be also possible that the controller 20 does not control the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc in accordance with the lean angle during a time period from when a signal for causing any one of the flashers 14L and 14R to flash is received from the 25 flasher switch 15F to when a signal for turning off the flashers 14L and 14R is received from the flasher switch 15F. In such a case, when the flasher 14L or 14L is flashing, ail of the sub headlight light sources (for example, the sub headlight light sources 13La to 13Lc) capable of illuminating the side where the flasher (for example, the flasher 14L) that is currently flashing is arranged may be turned on in the full-light state.

[0061]

FIG. 3 is a diagram schematically showing, in a front elevational view, a screen light distribution of the motorcycle 10 of FIG. 1 when the motorcycle 10 is in an inclined state.

The motorcycle 10 is inclined to the left at a lean angle B relative to a ground G. The lean angle B corresponds to the third reference value. An illumination range LB of the low 35 beam light source 11L is inclined downward to the left. A cut-off line L_o of the low beam light source 11 L, which defines an upper boundary line of the illumination range LB, is inclined downward to the left similarly to the illumination range LB. Accordingly, in a case where only e

the low beam light source 11L illuminâtes ahead, an illumination range produced in an inner left area ahead in the advancing direction is reduced. An optical axis A_o of the low beam light source 11L is located below a horizontal line H of the low beam light source 11L.

[0062]

In the motorcycle 10, however, the lean angle B has reached the third reference value and therefore the sub headlight light sources 13La to 13Lc are turned on in the full-light state, so that illumination ranges SHi to SH3 of the sub headlight light sources 13La to 13Lc cover a space between the horizontal line H and the cut-off line L_o of the low beam light source 11 L. As a resuit, a wide illumination range is ensured in the inner left area ahead in a path. This 10 improves the visibility ahead in the path at a time of running in a curve. Additionally, since cutoff Unes L1 to L₃ of the illumination ranges SH1 to SH₃ and optical axes Ai to A₃ are located below the horizontal line H, occurrence of glare is prevented.

[0063]

FIG. 4 is a diagram schematically showing a screen light distribution of the motorcycle 15 10 of FIG. 1 when the motorcycle 10 is in an upright state.

FIG. 4 shows a state where the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc are turned on in the dimmed state at a time of running straight ahead. The cut-off line Lo of the illumination range LB and the optical axis Ao of the low beam light source 11L are located below the horizontal line H. The illumination ranges SH1 to SH₃ of the sub headlight light 20 sources 13La to 13Lc, 13Ra to 13Rc include a space above the horizontal line H. The sub headlight light sources 13La to 13Lc, 13Ra to 13Rc are turned on in the dimmed state under a state where the optical axes Ai to A₃ are directed above a horizontal plane.

[0064]

In the motorcycle 10, the illumination ranges SH1 to SH₃ produced when the sub 25 headlight light sources 13La to 13Lc are turned on in the dimmed state (FIG. 4) are located higher than the illumination ranges SHi to SH₃ produced when the sub headlight light sources 13La to 13Lc are turned on in accordance with the lean angle B of the motorcycle 10 (FIG. 3). Similarly, the optical axes Ai to A₃ occurring when the sub headlight light sources 13La to 13Lc are turned on in the dimmed state (FIG. 4) are directed upward relative to the optical axes Ai to 30 A₃ occurring when the sub headlight light sources 13La to 13Lc are turned on in accordance with the lean angle B of the motorcycle 10 (FIG. 3). Accordingly, the conspicuity of the sub headlight light sources 13La to 13Lc is ensured at a time of performing the answerback operation. Additionally, the conspicuity thereof as a position light is improved.

[0065]

FIGS. 5(a) to 5(c) are diagrams showing an example of a lighting pattern of the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc of the motorcycle 10 of FIG. 1, and FIGS. 5(d) to 5(f) are diagrams showing another example of the lighting pattern. In FIG. 5, hatching <1 is given to the sub headlight light sources that are currently turned on.

[0066]

In a case where communication between the answerback main unit 21 and the remote control key 25 satisfies the predetermined condition, the controller 20 controls the sub headlight o light sources 13La to 13Lc, 13Ra to 13Rc.

For example, firstly, as shown in FIG. 5(a), the sub headlight light sources 13La and 13Ra are turned off while the sub headlight light sources 13Lb, 13Lc, 13Rb, and 13Rc are turned on in the full-light state for a predetermined time period.

Then, as shown in FIG. 5(b), the sub headlight light sources 13Lb and 13Rb are turned off while the sub headlight light sources 13La, 13Lc, 13Ra, and 13Rc are turned on in the full-light state for a predetermined time period.

Then, as shown in FIG. 5(c), the sub headlight light sources 13Lc and 13Rc are turned off while the sub headlight light sources 13La, 13Lb, 13Ra, and 13Rb are turned on in the full-light state for a predetermined time period.

Then, the lighting in the manner shown in FIGS. 5(a) to 5(c) is sequentially repeated a plurality of times. Thereby, the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc are caused to flash.

[0067]

Alternatively, the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc may be 20 controlled as follows.

For example, firstly, as shown in FIG. 5(d), the sub headlight light sources 13Lb, 13Lc, 13Rb, and 13Rc are turned off while the sub headlight light sources 13La and 13Ra are turned on in the full-light state for a predetermined time period.

Then, as shown in FIG. 5(e), the sub headlight light sources 13La, 13Lc, 13Ra, and 25 13Rc are turned off while the sub headlight light sources 13Lb and 13Rb are turned on in the full-light state for a predetermined time period.

Then, as shown in FIG. 5(f), the sub headlight light sources 13La, 13Lb, 13Ra, and 13Rb are turned off while the sub headlight light sources 13Lc and 13Rc are turned on in the full-light state for a predetermined time period.

Then, the lighting in the manner shown in FIGS. 5(d) to 5(f) is sequentially repeated a plurality of times. Thereby, the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc are caused to flash.

[0068]

As thus far described, in the motorcycle 10 according to this embodiment, the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc are turned on in accordance with the lean angle. Thereby, the field of view can be ensured in an area at the inner side of a curve and ahead in the advancing direction (see FIG. 3). Moreover, at a time of parking or stopping, an e

answerback function can be achieved, and at a time of running straight ahead, the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc are able to function as a position light (see FIG. 4). Thus, the sub headlight light sources 13La to 13Lc, 13Ra to 13Rc serve a plurality of functions, which can suppress a size increase of the device as a whole.

[0069]

In the motorcycle 10 according to this embodiment, the sub headlight 13 is composed of the sub headlight units 13L and 13R, each of which is provided at each side with respect to the width direction of the vehicle. However, the présent teaching is not limited to this example. For example, in a possible configuration, the sub headlight units 13L and 13R each provided at 10 each side with respect to the width direction of the vehicle are formed intégral with each other, as a single sub headlight unit. In this case, the single sub headlight unit has, at each side thereof with respect to the width direction of the vehicle, a plurality of headlight light sources that generate illumination ranges at one side with respect to the width direction of the vehicle.

[0070]

This embodiment describes a case where each of the sub headlight units 13L and

13R is a physically integrated unit. However, the présent teaching is not limited to this example. It may be possible that the sub headlight unit 13L is physically divided into the sub headlight light sources 13La to 13Lc. In this case, it may be possible that these sub headlight light sources 13La to 13Lc are assembled into a single sub headlight unit 13L which is then 20 installed in the motorcycle 10 (vehicle). It may be also possible that each of the sub headlight light sources 13La to 13Lc is individually installed in the motorcycle 10. In this case, the sub headlight light sources 13La to 13Lc, in a state of being installed in the motorcycle 10, constitute a single sub headlight unit 13L.

[0071]

In this embodiment, the sub headlight units 13L and 13R are members separate from the main headlight 11. However, the présent teaching is not limited to this example. It may be acceptable that a sub headlight unit is integrated with a main headlight. In this case, the sub headlight unit includes the main headlight.

[0072]

The attitude détection sensor 22 and the vehicle speed sensor 23 correspond to a détection part for detecting variables available for obtaining the lean angle of the motorcycle 10. Although the détection part includes the attitude détection sensor 22 and the vehicle speed sensor 23 in this embodiment, the présent teaching is not limited to this example. For example, the détection part may include the attitude détection sensor 22 while not including the vehicle speed sensor 23.

The answerback main unit 21 includes a communication device and a control unit. The communication device corresponds to a communication part of the présent teaching. The

Ο controller 20 and the control unit correspond to a control part of the présent teaching. However, a hardware configuration of the présent teaching is not limited to this example. For example, the answerback main unit 21 and the controller 20 may be integrated with each other. In a case where the answerback function is not provided, the controller 20 corresponds to the control part of the présent teaching. The control part détermines whether or not the lean angle of the motorcycle 10 has reached the reference value based on the variables detected by the détection part. At this time, it is not always necessary that the control part calculâtes the lean angle. No particular limitation is put on details of processing performed in the control part. For example, it may be possible that the memory provided in the controller 20 serving as the control part stores, in the form of data, a table in which the angular velocity (roll rate) and the vehicle speed are associated with a resuit of whether or not the lean angle has reached the first reference value. In this case, the control part refers to the table based on the angular velocity and the vehicle speed, and thereby can détermine whether or not the lean angle has reached the first reference value without calculating the lean angle.

[0073]

In this embodiment, the lean angle is the angle of inclination of the vehicle body to the inner side of a curve relative to the upright state (vertical direction). However, the présent teaching is not limited to this example. The lean angle may be the angle of inclination of the vehicle body to the inner side of a curve relative to a direction perpendicular to a road surface. As a method and a device for measuring the angle of inclination of the vehicle body to the inner side of a curve relative to the direction perpendicular to the road surface, conventionally known ones are adoptable.

[0074]

This embodiment describes a case where the sub headlight units 13L and 13R are members separate from the control part (the controller 20 and the control unit of the answerback main unit 21), the communication part (the communication device of the answerback main unit 21), and the détection part (the attitude détection sensor 22 and the vehicle speed sensor 23). However, the présent teaching is not limited to this example. The sub headlight unit may include at least one of the control part, the communication part, and the détection part.

[0075]

In this embodiment, three sub headlight light sources are provided at each side of the vehicle with respect to the width direction of the vehicle. In the présent teaching, however, no particular limitation is put on the number of sub headlight light sources. The number of sub headlight light sources may be one. It is not always necessary that the sub headlight light source is provided at each side of the vehicle with respect to the width direction of the vehicle.

[0076]

Φ

This embodiment describes a case where the sub headlight light source is turned on in accordance with the lean angle. However, the présent teaching is not limited to this example. The sub headlight light source may be configured such that a turn-on function in accordance with the lean angle is manually activated or deactivated. To be spécifie, it may be possible that the function is manually put into a standby state and, in the standby state, the sub headlight light source is turned on in accordance with the lean angle. In this case as well, the sub headlight light source is turned on not manually but in accordance with the lean angle. In the flasher, on the other hand, flashing/turn-off is manually switched. Also, in the main headlight, the illuminating direction is manually switched. In this manner, the sub headlight light source is different from the flasher and the main headlight.

The sub headlight light source may be also configured such that an instruction for turn-on or turn-off is manually inputted. In such a case, when the instruction is not inputted, the brightness of the sub headlight light source is changed in accordance with the lean angle, while when the instruction is inputted, turn-on or turn-off is performed in accordance with the instruction. For example, when the instruction for turn-on is inputted, the sub headlight light source is turned on irrespective of the lean angle. When the instruction for turn-off is inputted, the sub headlight light source is turned off irrespective of the lean angle. In such a case, the sub headlight System includes an input part (for example, a switch) to which the instruction for turning on or off the sub headlight light source is manually inputted. When the instruction is inputted, the control part turns on or off the sub headlight light source in accordance with the instruction. When the instruction is not inputted, the control part changes the brightness of the sub headlight light source in accordance with the lean angle. In this case as well, the sub headlight light source is different from the flasher and the main headlight, in that a function of turning on the sub headlight light source in accordance with the lean angle is provided.

The sub headlight light source may be configured such that, when the lean angle is equal to or larger than a minimum reference value, the brightness is changed in accordance with the lean angle, while when the lean angle is less than the minimum reference value (for example, at a time of running straight ahead), the brightness is manually changed. In this case as well, the sub headlight light source is different from the flasher and the main headlight, in that a function of turning on the sub headlight light source in accordance with the lean angle is provided.

[0077]

In the description of this embodiment, the sub headlight light source is, when turned on in accordance with the lean angle, turned on in the full-light state. However, the présent teaching is not limited to this example. It suffices that the amount of light emitted when the sub headlight light source is turned on in accordance with the lean angle is greater than the amount of light emitted when the sub headlight light source is turned on or caused to flash at a time of ο

parking or stopping or at a time of running straight ahead.

[0078]

In the description of this embodiment, the sub headlight light source is turned on in accordance with the lean angle. Here, the sub headlight light source is turned on in 5 accordance with the lean angle because the sub headlight light source functions mainly as a light for ensuring the field of view of the rider of the vehicle. Therefore, in a well-lit situation, for example, in daytime, the sub headlight light source may not necessarily be turned on in accordance with the lean angle. In this case, the state at a time of parking or stopping or at a time of running straight ahead, in which the sub headlight light source is turned on or caused to 10 flash with the amount of light being smaller than the amount of light emitted when the sub headlight light source is turned on in accordance with the lean angle, may be continued even in a case where the lean angle is detected. According to the présent teaching, the time of running straight ahead includes not only a time of running under a state where the vehicle is in lhe upright state but also a time of running under a state where the lean angle of the vehicle is 15 less than the minimum reference value.

[0079]

According to the présent teaching, no particular limitation is put on the lighting pattern of the sub headlight light sources given by the answerback function. It is préférable that the lighting pattern (the order and time of turning on) of sub headlight light sources given by the 20 answerback function is different from the lighting pattern of the sub headlight light sources given in accordance with the lean angle.

[0080]

In the description of this embodiment, the sub headlight light sources are used for achievement of the answerback function and also used as a position light. Instead, the sub 25 headlight light sources may be used for either one of them. According to the présent teaching, intended use of the sub headlight light sources is not limited to them. For example, in a possible configuration, at a time of switching between a state where an immobilizer is set (a state where the vehicle is not able to run with its own power) and a state where the setting of the immobilizer is disabled (a state where the vehicle is able to run with its own power), the sub j0 headlight light sources function as a status display by being turned on or caused to flash for a predetermined time period with the amount of light per unit time being reduced as compared with the amount of light per unit time emitted when the vehicle is turned on in accordance with the lean angle. Moreover, in another possible configuration, the sub headlight light sources are used for an alarm and/or a panic alarm of a theft warning device. Furthermore, the sub 35 headlight light sources can be used as a passing light. That is, it may be possible that, when the rider opérâtes a passing switch at a time of running straight ahead, the sub headlight light sources are turned on or caused to flash for a predetermined time period. In this case, a time

Ο period of the turn-on or flashing is the predetermined time period (that is, temporary). Thus, a time period in which the turn-on or flashing is continued is short. Therefore, the amount of light per unit time is small. Here, the predetermined time period may be, for example, a time period that has been set in advance, or a time period from when the passing switch is tumed on to when the passing switch is tumed off. More specifically, the présent teaching can adopt the following configuration.

[0081] (A) A sub headlight System for use in a vehicle that leans into turns, the sub headlight System including:

the sub headlight unit according to any one of (1) to (5) described above;

an immobilizer that stops, through an electronic method, a function of a device (such as a motor) for running the vehicle, to thereby prevent the vehicle from running by itself;

an immobilizer control device that sets the immobilizer and disables the setting of the immobilizer;

a détection part that detects a variable (such as a vehicle speed and a roll rate) for obtaining a lean angle of the vehicle; and a control part that controls light émission of a sub headlight light source, wherein the control part turns on the sub headlight light source in accordance with the lean angle of the vehicle and, when the immobilizer control device sets the immobilizer and disables the setting of the immobilizer at a time of parking, the control part causes the sub headlight light source to be tumed on or flash with the amount of light per unit time being smaller than the amount of light per unit time emitted when the sub headlight light source is tumed on in accordance with the lean angle of the vehicle.

[0082] (B) A sub headlight System for use in a vehicle that leans into turns, the sub headlight System including:

the sub headlight unit according to any one of (1) to (5) described above;

a change détection part (such as an inclination sensor and a vibration sensor) that detects a change caused by intrusion or interférence into the vehicle;

a détection part that detects a variable (such as a vehicle speed and a roll rate) for obtaining a lean angle of the vehicle; and a control part that controls light émission of a sub headlight light source, wherein the control part turns on the sub headlight light source in accordance with the lean angle of the vehicle and, at a time of parking, in accordance with détection of a change by the change détection part, the control part causes the sub headlight light source to be tumed on or flash with the amount of light per unit time being reduced as compared with the amount of e

light per unit time emitted when the sub headlight light source is turned on in accordance with the lean angle of the vehicle.

[0083] (C) A sub headlight System for use in a vehicle that leans into turns, the sub headlight System including:

the sub headlight unit according to any one of (1) to (5) described above; a passing switch configured to be operated by a rider;

a détection part that detects a variable (such as a vehicle speed and a roll rate) for obtaining a lean angle of the vehicle; and a control part that controls light émission of a sub headlight light source, wherein the control part turns on the sub headlight light source in accordance with the lean angle of the vehicle and, in a case where the passing switch is operated at a time when the vehicle is running straight ahead, the control part causes the sub headlight light source to be turned on or flash with the amount of light per unit time being reduced as compared with the amount of light per unit time emitted when the sub headlight light source is turned on in accordance with the lean angle of the vehicle.

[0084]

In the conventional techniques, as disclosed in JP4806550, when the lean angle increases, the sub headlight light source is turned on, while when the lean angle decreases, the sub headlight light source is turned off. The reason for turning off the sub headlight light source is for the purpose of preventing glare. That is, conventionally, there hâve been reasonable grounds for turning off the sub headlight light source at a time of parking or stopping and at a time of running straight ahead. The causes of glare are the orientation (illumination range) and brightness of the sub headlight light source.

As for the brightness of the sub headlight light source, the sub headlight light source is a light intended mainly to improve the visibility for the rider and therefore, in normal cases, the brightness of the sub headlight light source is set high. However, in a case of achieving a function other than the function for improving the visibility for the rider, that is, in a case of achieving a function for improving the conspicuity of the own vehicle when seen from the surroundings, a réduction in the brightness is allowed. This can solve the problem of glare.

As for the orientation of the sub headlight light source, on the other hand, the fact that a disadvantage of glaring has conventionally existed means that the conspicuity of the own vehicle when seen from the surroundings is high. Therefore, adjusting the brightness of the sub headlight light source in the above-described manner to thereby solve the problem of glare makes it possible that the disadvantage of glaring is turned into the advantage of high conspicuity of the own vehicle when seen from the surroundings, which can be thus leveraged. This idea underlies the accomplishment of the présent teaching.

e

The conventional techniques do not involve the technical idea that a headlight that produces an illumination range including a space above a horizontal plane when the vehicle is in the upright state is turned on with a reduced amount of light per unit time so that the headlight is used for achievement of the answerback function and also used as a position light providing 5 excellent conspicuity of the own vehicle when seen from the surroundings. Moreover, the conventional techniques do not involve the technical idea that a headlight that produces an illumination range including a space above the horizontal plane when the vehicle is in the upright state is turned on while the vehicle is in the upright state. Therefore, the présent teaching is based on the technical ideas different from those of the conventional techniques, 10 and exerts effects that cannot be obtained from the conventional techniques.

[0085]

The embodiments also discloses a method for controlling light émission of a sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc for use in a vehicle that leans into turns comprising:

detecting a variable used for obtaining a lean angle of the vehicle, turning on the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc in accordance with the lean angle of the vehicle and, at a time of parking or stopping or at a time of running straight ahead, causing the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc to be turned on or flash with an amount of light per unit time being reduced as compared with an amount of light per unit time emitted when the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc is turned on in accordance with the lean angle of the vehicle.

According to the method for controlling light émission of the sub headlight light source, the sub headlight system comprising a communication part that communicates with a portable communication device that is portable for a rider, wherein the method further comprises:

turning on the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc in accordance with the lean angle of the vehicle and, in a case where communication between the communication part and the portable communication device satisfies a predetermined condition at a time of parking or stopping, causing the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc to be turned on or flash with an amount of light per unit time being reduced as compared with an amount of light per unit time emitted when the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc is turned on in accordance with the lean angle of the vehicle.

The method for controlling light émission of the sub headlight light source further comprises turning on the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc in accordance with the lean angle of the vehicle and, at a time of running straight ahead, turning 35 on the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc with the amount of light per unit time being reduced.

φ

The method for controlling light émission of the sub headlight light source further comprising:

producing an illumination range of the sub headlight light source 13La,13Lb,13l_c,13Ra,13Rb,13Rc when the sub headlight light source

13La,13Lb,13Lc,13Ra,13Rb,13Rc is turned on or caused to flash with the amount of light per unit time being reduced located higherthan an illumination range of the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc produced when the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc is turned on in accordance with the lean angle of the vehicle.

The method for controlling light émission of the sub headlight light source further lü comprising:

directing an optical axis of the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc occurring when the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc is turned on or caused to flash with the amount of light per unit time being reduced upward relative to an optical axis of the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc occurring when the sub 15 headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc is turned on in accordance with the lean angle of the vehicle, and/or turning the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc on or causing to flash with the amount of light per unit time being reduced, under a state where an optical axis of the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc is directed at or above a horizontal 20 plane.

According to the method for controlling light émission of the sub headlight light source, when the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc is turned on in accordance with the lean angle of the vehicle, locating a cut-off line of the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc at or below a horizontal line of the sub headlight light 25 source 13La,13Lb,13Lc,13Ra,13Rb,13Rc, while when the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc is turned on or caused to flash with the amount of light per unit time being reduced, the cut-off line of the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc is wholly or partially located in a space above the horizontal line of the sub headlight light source 13La,13Lb,13Lc,13Ra,13Rb,13Rc.

[0086] [DESCRIPTION OFTHE REFERENCE NUMERALS] motorcycle (vehicle that leans into turns) main headlight

11H high beam light source

11L low beam light source handlebar sub headlight φ

13L, 13R sub headlight unit

13La, 13Lb, 13Lc, 13Ra, 13Rb, 13Rc sub headlight light source

14L, 14R flasher

16

22 operation switch front wheel frontfork front cover controller answerback main unit attitude détection sensor vehicle speed sensor remote control key

Claims

1. A sub headlight System for use in a vehicle that leans into turns, the sub headlight

System (13L, 13R) comprising:

a sub headlight unit including a sub headlight light source(13La, 13Lb, 13Lc, 13Ra, 13Rb, 13Rc) that illuminâtes an area ahead and outward of the vehicle with respect to a width direction of the vehicle;

a control unit arranged and programmed to control light émission of the sub headlight light source; and a détection unit that detects a variable used to obtain a lean angle of the vehicle; wherein the sub headlight light source is configured to, when the vehicle is in an upright state, produce an illumination range including an area above a horizontal plane extending horizontally from the sub headlight light source( 13La, 13Lb, 13Lc, 13Ra, 13Rb, 13Rc);

the control unit is arranged and programmed to calculate the lean angle of the vehicle while the vehicle is running and to turn on the sub headlight light source in accordancewith the calculated lean angle of the vehicle to émit an amount of light per unit of time;

and the control unit is arranged and programmed to, at a time of parking or stopping or at a time of running in the upright state, cause the sub headlight light source (13La, 13Lb, 13Lc, 13Ra, 13Rb, 13Rc)to be turned on or to flash to émit an amount of light per unit of time that is reduced compared to the amount of light per unit of time emitted when the sub headlight light source (13La, 13Lb, 13Lc, 13Ra, 13Rb, 13Rc) is turned on in accordance with the lean angle of the vehicle while the vehicle is running.

2. The sub headlight System according to claim 1, wherein an illumination range of the sub headlight light source (13La, 13Lb, 13Lc, 13Ra, 13Rb, 13Rc) produced when the sub headlight light source (13La, 13Lb, 13Lc, 13Ra, 13Rb, 13Rc) is turned on or caused to flash with the amount of light per unit of time being reduced is located higher than an illumination range of the sub headlight light source (13La, 13Lb, 13Lc, 13Ra,13Rb, 13Rc) produced when the sub headlight light source (13La,13Lb, 13Lc, 13Ra,13Rb, 13Rc) is turned on in accordance with the lean angle of the vehicle.

3. The sub headlight System according to claim 1, wherein an optical axis of the sub headlight light source (13La, 13Lb, 13Lc, 13Ra, 13Rb, 13Rc) occurring when the sub headlight light source (13La,13Lb, 13Lc,13Ra, 13Rb, 13Rc) is turned on or caused to flash with the amount of light per unit of time being reduced is directed upward relative to an optical axis of the sub headlight light source (13La, 13Lb, 13Lc, 13Ra, 13Rb, 13Rc) occurring when the sub headlight light source (13La, 13Lb, 13Lc, 13Ra,13Rb,13Rc) is turned on in accordance with the lean angle of the vehicle.

4. The sub headlight System according to claim 1, wherein the sub headlight light source (13La, 13Lb, 13Lc, 13Ra, 13Rb, 13Rc) is turned on or caused to flash with the amount of light per unit of time being reduced, under a state where an optical axis of the sub headlight light source (13La,13Lb, 13Lc, 13Ra, 13Rb, 13Rc) is directed at or above the horizontal plane.

5. The sub headlight System according to claim 1, wherein when the sub headlight light source(13La,13Lb,13Lc,13Ra,13Rb,13Rc) is turned on in accordance with the lean angle of the vehicle, a cut-off line of the sub headlight light source (13La,13Lb,13Lc,13Ra, 13Rb,13Rc) is located at or below the horizontal plane including the sub headlight light source (13La, 13Lb, 13Lc,13Ra, 13Rb, 13Rc), while when the sub headlight light source (13La,13Lb, 13Lc,13Ra,13Rb,13Rc) is turned on or caused to flash with the amount of light per unit of time being reduced, the cut-off line of the sub headlight light source (13La, 13Lb, 13Lc, 13Ra, 13Rb, 13Rc) is wholly or partially located in an area above the horizontal plane including the sub headlight light source(13La,13Lb, 13Lc,13Ra,13Rb,13Rc).

6. The sub headlight System according to claim 1, further comprising a communication unit that communicates with a portable communication device that is portable for a rider, wherein the control unit turns on the sub headlight light source(13La,13Lb,13Lc, 13Ra, 13Rb, 13Rc) in accordance with the lean angle of the vehicle and, in a case where communication between the communication unit and the portable communication device satisfies a predetermined condition at a time of parking or stopping, the control unit causes the sub headlight light source (13La,13Lb, 13Lc,13Ra,13Rb, 13Rc) to be turned on or flash with the amount of light per unit of time being reduced as compared with the amount of light per unit of time emitted when the sub headlight light source (13La, 13Lb, 13Lc, 13Ra, 13Rb, 13Rc) is turned on in accordance with the lean angle of the vehicle.

7. The sub headlight System according to claim 1, wherein the control unit turns on the sub headlight light source (13La, 13Lb, 13Lc, 13Ra, 13Rb, 13Rc) in accordance with the lean angle of the vehicle and, at a time of running in the upright state, the control unit «

turns on the sub headlight light source (13La, 13Lb, 13Lc, 13Ra, 13Rb, 13Rc) with the amount of light per unit of time being reduced.

8. A vehicle that leans into turns comprising:

5 the sub headlight System according to claim 1.