Vehicle lighting device control device

Abstract

To provide a technique capable of performing automatic leveling control, which acquires an inclination angle of a vehicle with respect to a horizontal plane from an inclination detecting device and adjusts a position of an optical axis of a vehicle lighting fixture, with higher accuracy.SOLUTION: Irradiation control parts 228L and 228R include: receiving parts 228L1 and 228R1 for receiving an inclination angle of a vehicle 300 with respect to a horizontal plane from an inclination detecting device; control parts 228L2 and 228R2 configured to generate a control signal for instructing adjustment for a position of an optical axis of the vehicle lighting fixture in response to change of the inclination angle, during stopping of the vehicle, and avoid generation of the control signal or generate a control signal for instructing the vehicle lighting fixture to maintain the position of the optical axis in response to change of the inclination angle, during traveling of the vehicle; and transmitting parts 228L3 and 228R3 for transmitting the control signal to a leveling control part 236 of the vehicle lighting fixture.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a vehicle lighting control device, a vehicle lamp, and a method for controlling a vehicle lamp, and more particularly to a vehicle lighting control device, a vehicle lamp, and a method for controlling a vehicle lamp used in automobiles, etc. [Background technology]

[0002] Conventionally, there is known an auto-leveling control that automatically adjusts the optical axis position of a vehicle headlamp according to the inclination angle of the vehicle to change the irradiation direction. In general, in the auto-leveling control, a vehicle height sensor is used as a vehicle inclination detection device, and the optical axis position of the headlamp is adjusted based on the pitch angle of the vehicle detected by the vehicle height sensor. In contrast, Patent Document 1 discloses a configuration in which the auto-leveling control is performed using a gravity sensor as the inclination detection device. In addition, Patent Document 2 discloses a configuration in which the auto-leveling control is performed using a three-dimensional gyro sensor as the inclination detection device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2000-085459 A [Patent Document 2] JP 2004-314856 A Summary of the Invention [Problem to be solved by the invention]

[0004] When an acceleration sensor (gravity sensor), gyro sensor, geomagnetic sensor, or the like is used as a vehicle tilt detection device, the auto-leveling system can be made less expensive and more lightweight than when a vehicle height sensor is used. However, the present inventors have come to recognize that the conventional auto-leveling control using an acceleration sensor or the like has the following problems.

[0005] That is, for example, the inclination angle detected by the acceleration sensor is the inclination angle of the vehicle relative to the horizontal plane, including the inclination angle of the road surface relative to the horizontal plane and the inclination angle of the vehicle relative to the road surface. On the other hand, the inclination angle of the vehicle required for the auto-leveling control is the inclination angle of the vehicle relative to the road surface. In contrast, in the conventional auto-leveling control, when the detection value of the acceleration sensor changes, the optical axis position is adjusted without distinguishing whether the change is a change in the inclination angle of the road surface relative to the horizontal plane or a change in the inclination angle of the vehicle relative to the road surface. Therefore, the conventional auto-leveling control using the acceleration sensor has room for improvement in terms of improving the adjustment accuracy of the optical axis position.

[0006] The present invention has been made based on this recognition by the inventors, and its purpose is to provide a technology that can perform auto-leveling control with greater precision, which obtains the vehicle inclination angle relative to a horizontal plane from an inclination detection device and adjusts the optical axis position of a vehicle lamp. [Means for solving the problem]

[0007] In order to solve the above problems, one aspect of the present invention is a control device for a vehicle lamp, the control device comprising: a receiving unit for receiving an inclination angle of the vehicle with respect to a horizontal plane from an inclination detection device; a control unit configured to generate a control signal that instructs adjustment of the optical axis position of the vehicle lamp in response to a change in the inclination angle while the vehicle is stopped, and to generate a control signal that avoids generation of the control signal or instructs maintenance of the optical axis position in response to a change in the inclination angle while the vehicle is moving; and a transmitting unit for transmitting the control signal to a optical axis adjustment unit of the vehicle lamp.

[0008] According to this aspect, it is possible to perform auto-leveling control with higher accuracy, in which the vehicle inclination angle with respect to the horizontal plane is obtained from the inclination detection device and the optical axis position of the vehicle lamp is adjusted.

[0009] In the above aspect, when the inclination angle of the vehicle with respect to the horizontal plane is called the total angle, this total angle includes a first angle which is the inclination angle of the road surface with respect to the horizontal plane and a second angle which is the inclination angle of the vehicle with respect to the road surface, and when the total angle changes while the vehicle is stopped, the control device may generate a control signal which instructs adjustment of the optical axis position by taking the change in the total angle as a change in the second angle. This aspect also makes it possible to perform auto-leveling control with higher accuracy, which acquires the inclination angle of the vehicle with respect to the horizontal plane from the inclination detection device and adjusts the optical axis position of the vehicle lamp.

[0010] In the above embodiment, the control unit may hold a reference value of the first angle and a reference value of the second angle, hold the first angle obtained from the detection value of the inclination detection device and the reference value of the second angle as a new reference value when the vehicle is stopped, and generate a control signal for instructing adjustment of the optical axis position using the second angle obtained from the detection value of the inclination detection device and the reference value of the first angle when the total angle changes while the vehicle is stopped, and hold the obtained second angle as a new reference value. This embodiment also makes it possible to perform auto-leveling control with higher accuracy, which obtains the inclination angle of the vehicle with respect to the horizontal plane from the inclination detection device and adjusts the optical axis position of the vehicle lamp.

[0011] In the above embodiment, the control unit may hold a reference value of the first angle and a reference value of the second angle, update the reference value of the first angle by taking a change in the total angle while the vehicle is moving as a change in the first angle, update the reference value of the second angle by taking a change in the total angle while the vehicle is stopped as a change in the second angle, and generate a control signal that instructs adjustment of the optical axis position using the updated reference value of the second angle. This embodiment also makes it possible to perform auto-leveling control with higher accuracy, which obtains the inclination angle of the vehicle with respect to the horizontal plane from the inclination detection device and adjusts the optical axis position of the vehicle lamp.

[0012] In the above aspect, the inclination detection device may be an acceleration sensor capable of detecting the inclination angle of the vehicle as a vector, and the control unit may correct the reference value of the first angle held to approach 0° when the difference between the square of the magnitude of the acceleration vector of the vehicle obtained from the vehicle speed sensor or the acceleration sensor a predetermined time after the vehicle starts and the square of the magnitude of the detection value vector of the acceleration sensor is equal to the square of the magnitude of the gravitational acceleration vector. In the above aspect, the inclination detection device may be an acceleration sensor capable of detecting the inclination angle of the vehicle as a vector, and the control unit may correct the reference value of the first angle obtained when the vehicle stops to approach 0° when the difference between the square of the magnitude of the acceleration vector of the vehicle obtained from the vehicle speed sensor or the acceleration sensor a predetermined time before the vehicle stops and the square of the magnitude of the detection value vector of the acceleration sensor is equal to the square of the magnitude of the gravitational acceleration vector. According to these aspects, the accuracy of the auto-leveling control can be further improved.

[0013] In the above aspect, the control unit may generate a control signal for instructing adjustment of the optical axis position using a second angle obtained from the detection value of the tilt detection device and the reference value of the first angle or the detection value of the tilt detection device last detected during the previous drive of the control device, and may hold the obtained second angle as a new reference value. According to this aspect, the accuracy of the auto-leveling control can be improved.

[0014] In the above aspect, the control unit may generate a control signal for instructing adjustment of the optical axis position using the held reference value of the second angle when the second angle obtained from the detection value of the tilt detection device and the reference value of the first angle exceeds a predetermined range. According to this aspect, it is possible to improve the visibility of the driver of the vehicle while reducing the risk of causing glare to the driver of the other vehicle. In the above aspect, the control unit may prohibit the generation of a control signal for instructing adjustment of the optical axis position thereafter when the second angle obtained from the detection value of the tilt detection device and the reference value of the first angle exceeds a predetermined range. According to this aspect, it is possible to reliably prevent glare from being caused to the driver of the other vehicle.

[0015] Another aspect of the present invention is a vehicular lamp, which is characterized in that the position of the optical axis is adjusted when the inclination angle of the vehicle with respect to the horizontal plane changes while the vehicle is stopped, and the position of the optical axis is maintained when the inclination angle of the vehicle with respect to the horizontal plane changes while the vehicle is moving.

[0016] Yet another aspect of the present invention is a method for controlling a vehicle lamp, the method being for adjusting a light axis of the vehicle lamp based on the inclination angle of the vehicle with respect to a horizontal plane detected by an inclination detection device, characterized in that the light axis position is adjusted when the inclination angle of the vehicle with respect to the road surface changes, and the light axis position is maintained when the inclination angle of the road surface with respect to the horizontal plane changes.

[0017] These aspects also make it possible to perform auto-leveling control with higher accuracy, in which the vehicle inclination angle with respect to the horizontal plane is obtained from the inclination detection device and the optical axis position of the vehicle lamp is adjusted. Effect of the Invention

[0018] According to the present invention, it is possible to perform auto-leveling control with higher accuracy, in which the vehicle inclination angle with respect to a horizontal plane is obtained from an inclination detection device and the optical axis position of a vehicle lamp is adjusted. [Brief description of the drawings]

[0019] [Figure 1] 1 is a schematic vertical sectional view illustrating an internal structure of a vehicle lighting system according to a first embodiment. [Diagram 2] 4 is a functional block diagram illustrating the operational cooperation between an illumination control unit of the headlamp unit and a vehicle control unit on the vehicle side. FIG. [Diagram 3] 4 is an auto-leveling control flowchart of the vehicle lighting system according to the first embodiment. [Figure 4] 10 is an explanatory diagram of an auto-leveling control by a vehicle lighting system according to a second embodiment. FIG. [Diagram 5]10 is a control flowchart of road surface horizontality determination and road surface angle correction when the vehicle starts moving in the vehicle lighting system according to the second embodiment. [Figure 6] 10 is a control flowchart of road surface horizontality determination and road surface angle correction when the vehicle stops in the vehicle lighting system according to the second embodiment. [Figure 7] 11 is a determination control flowchart of a vehicle attitude angle θv in a vehicle lighting system according to a third embodiment. [Figure 8] 13 is another determination control flowchart for the vehicle attitude angle θv in the vehicle lamp system according to the third embodiment. [Figure 9] 10 is an auto-leveling control flowchart of a vehicle lighting system according to a fourth embodiment. [Figure 10] 10 is a functional block diagram illustrating the operational cooperation between a headlamp unit, a vehicle control unit, and a leveling ECU in a vehicle lighting system according to a modified example. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] The present invention will be described below based on preferred embodiments with reference to the drawings. The same or equivalent components, parts, and processes shown in each drawing are given the same reference numerals, and duplicated descriptions are omitted as appropriate. In addition, the embodiments are illustrative rather than limiting the invention, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

[0021] (Embodiment 1) FIG. 1 is a schematic vertical cross-sectional view illustrating the internal structure of a vehicle lighting system according to a first embodiment. The vehicle lighting system 200 of this embodiment is a variable light distribution headlamp system in which a pair of symmetrically formed headlamp units are arranged on the left and right sides of the vehicle in the vehicle width direction. The left and right headlamp units have substantially the same configuration except for having a symmetrical structure, so the structure of the right headlamp unit 210R will be described below, and the description of the left headlamp unit will be omitted as appropriate. When describing each member of the left headlamp unit, for convenience of explanation, the same reference numerals as the corresponding members of the headlamp unit 210R will be used for each member.

[0022] The headlamp unit 210R has a lamp body 212 with an opening on the vehicle front side, and a light-transmitting cover 214 that covers this opening. The lamp body 212 has a removable cover 212a on the vehicle rear side that can be removed when replacing the bulb 14, etc. The lamp body 212 and the light-transmitting cover 214 form a lamp chamber 216. The lamp chamber 216 houses a lamp unit 10 (vehicle lamp) that irradiates light forward of the vehicle.

[0023] A lamp bracket 218 having a pivot mechanism 218a that serves as the center of vertical and horizontal swing of the lamp unit 10 is formed in a part of the lamp unit 10. The lamp bracket 218 is screwed into an aiming adjustment screw 220 that is rotatably supported on the wall surface of the lamp body 212. Therefore, the lamp unit 10 is fixed at a predetermined position in the lamp chamber 216 determined by the adjustment state of the aiming adjustment screw 220, and can change its posture to a forward or backward tilt posture, etc., with the pivot mechanism 218a as the center based on that position.

[0024] In addition, a rotating shaft 222a of a swivel actuator 222 for configuring a curved road variable light distribution headlamp (Adaptive Front-lighting System: AFS) that illuminates the traveling direction when traveling on a curved road is fixed to the lower surface of the lighting unit 10. The swivel actuator 222 rotates (swivels) the lighting unit 10 in the traveling direction around the pivot mechanism 218a based on steering amount data provided from the vehicle side, shape data of the traveling road provided from the navigation system, and the relationship between the relative position of the vehicle and a preceding vehicle including an oncoming vehicle and a preceding vehicle. As a result, the illumination area of ​​the lighting unit 10 faces the end of the curve of the curved road instead of the front of the vehicle, improving the driver's forward visibility. The swivel actuator 222 can be configured with, for example, a stepping motor. In addition, when the swivel angle is a fixed value, a solenoid or the like can be used. The swivel actuator 222 is fixed to a unit bracket 224.

[0025] A leveling actuator 226 disposed outside the lamp body 212 is connected to the unit bracket 224. The leveling actuator 226 is composed of, for example, a motor that expands and contracts the rod 226a in the directions of the arrows M and N. When the rod 226a expands in the direction of the arrow M, the lamp unit 10 swings around the pivot mechanism 218a so as to assume a rearward tilting posture. Conversely, when the rod 226a contracts in the direction of the arrow N, the lamp unit 10 swings around the pivot mechanism 218a so as to assume a forward tilting posture. When the lamp unit 10 assumes a rearward tilting posture, a leveling adjustment can be performed to orient the pitch angle of the optical axis O, that is, the vertical angle of the optical axis O, upward. When the lamp unit 10 assumes a forward tilting posture, a leveling adjustment can be performed to orient the pitch angle of the optical axis O downward. By performing such a leveling adjustment, the optical axis can be adjusted according to the vehicle posture. As a result, the reach of the forward illumination light by the vehicle lamp system 200 can be adjusted to an optimal distance.

[0026] An irradiation control unit 228 (control device) that controls turning on and off the lamp unit 10, controls the formation of a light distribution pattern, adjusts the optical axis of the lamp unit 10, and the like is disposed on the inner wall surface of the lamp chamber 216 below the lamp unit 10. In the case of FIG. 1, an irradiation control unit 228R for controlling the headlamp unit 210R is disposed. This irradiation control unit 228R also controls the swivel actuator 222, the leveling actuator 226, and the like. The irradiation control unit 228R may be provided outside the headlamp unit 210R.

[0027] The lamp unit 10 may include an aiming adjustment mechanism. For example, an aiming pivot mechanism (not shown) that serves as a swing center during aiming adjustment is disposed at a connection portion between the rod 226a of the leveling actuator 226 and the unit bracket 224. The above-mentioned aiming adjustment screws 220 are disposed at intervals in the vehicle width direction on the lamp bracket 218. For example, when the two aiming adjustment screws 220 are rotated counterclockwise, the lamp unit 10 assumes a forward tilting position around the aiming pivot mechanism, and the optical axis O is adjusted downward. Similarly, when the two aiming adjustment screws 220 are rotated clockwise, the lamp unit 10 assumes a backward tilting position around the aiming pivot mechanism, and the optical axis O is adjusted upward. When the aiming adjustment screw 220 on the left side in the vehicle width direction is rotated counterclockwise, the lamp unit 10 assumes a right-turning position around the aiming pivot mechanism, and the optical axis O is adjusted to the right. Furthermore, when the aiming adjustment screw 220 on the right side in the vehicle width direction is rotated counterclockwise, the lamp unit 10 is rotated leftward around the aiming pivot mechanism, and the optical axis O is adjusted leftward. This aiming adjustment is performed when the vehicle is shipped, during vehicle inspection, and when the headlamp unit 210R is replaced. Then, the headlamp unit 210R is adjusted to a design-defined position, and the formation of the light distribution pattern and the adjustment of the optical axis position are controlled based on this position.

[0028] The lamp unit 10 includes a shade mechanism 18 including a rotating shade 12, a lamp housing 17 that supports a bulb 14 as a light source and a reflector 16 on its inner wall, and a projection lens 20. For the bulb 14, for example, an incandescent bulb, a halogen lamp, a discharge bulb, an LED, or the like can be used. In this embodiment, an example in which the bulb 14 is a halogen lamp is shown. The reflector 16 reflects the light emitted from the bulb 14. Then, a portion of the light from the bulb 14 and the light reflected by the reflector 16 is guided to the projection lens 20 via the rotating shade 12.

[0029] The rotating shade 12 is a cylindrical member that can rotate around a rotation axis 12a, and includes a cutout portion cut out in the axial direction and multiple shade plates (not shown). Either the cutout portion or the shade plate is moved along the optical axis O to form a predetermined light distribution pattern. At least a part of the reflector 16 is ellipsoidal, and this ellipsoidal surface is set so that the cross-sectional shape including the optical axis O of the lamp unit 10 is at least a part of an elliptical shape. The ellipsoidal part of the reflector 16 has a first focal point approximately at the center of the bulb 14 and a second focal point on the rear focal plane of the projection lens 20.

[0030] The projection lens 20 is disposed on an optical axis O extending in the front-rear direction of the vehicle. The bulb 14 is disposed rearward of a rear focal plane, which is a focal plane including the rear focal point of the projection lens 20. The projection lens 20 is made of a plano-convex aspheric lens having a convex front surface and a flat rear surface, and projects a light source image formed on the rear focal plane as an inverted image onto a virtual vertical screen in front of the vehicle lighting system 200. Note that the configuration of the lighting unit 10 is not particularly limited to this, and may be a reflective lighting unit not having the projection lens 20.

[0031] 2 is a functional block diagram for explaining the operational cooperation between the illumination control unit of the headlamp unit configured as described above and the vehicle control unit on the vehicle side. As described above, the right headlamp unit 210R and the left headlamp unit 210L are basically configured the same, so only the headlamp unit 210R side will be explained and the explanation of the headlamp unit 210L side will be omitted.

[0032] The illumination control unit 228R of the headlamp unit 210R has a receiving unit 228R1, a control unit 228R2, a transmitting unit 228R3, and a memory 228R4. The illumination control unit 228R controls the power supply circuit 230 based on information obtained from a vehicle control unit 302 (vehicle control ECU) mounted on the vehicle 300, and executes lighting control of the bulb 14. The illumination control unit 228R also controls the variable shade control unit 232, the swivel control unit 234, and the leveling control unit 236 (optical axis adjustment unit) based on information obtained from the vehicle control unit 302. Various information transmitted from the vehicle control unit 302 is received by the receiving unit 228R1, and various control signals are generated by the control unit 228R2 from the information and information stored in the memory 228R4 as necessary. Then, the control signal is transmitted by the transmission section 228R3 to the power supply circuit 230, the variable shade control section 232, the swivel control section 234, the leveling control section 236, etc. of the lighting unit 10. The memory 228R4 is, for example, a non-volatile memory.

[0033] The variable shade control unit 232 controls the rotation of a motor 238 connected to the rotating shaft 12a of the rotating shade 12 via a gear mechanism to move a desired shade plate or cutout onto the optical axis O. The variable shade control unit 232 receives rotation information indicating the rotation state of the rotating shade 12 from detection sensors such as an encoder provided on the motor 238 and the rotating shade 12. This allows accurate rotation control through feedback control. The swivel control unit 234 also controls the swivel actuator 222 to adjust the angle of the optical axis O of the lamp unit 10 in the vehicle width direction (left and right direction). For example, when turning, such as traveling on a curved road or turning right or left, the optical axis O of the lamp unit 10 is directed in the direction of travel.

[0034] The leveling control section 236 controls the leveling actuator 226 to adjust the optical axis O of the lighting unit 10 in the vehicle up-down direction (pitch angle direction). For example, the attitude of the lighting unit 10 is adjusted according to the forward or backward tilt of the vehicle attitude when the load amount or the number of passengers increases or decreases, and the reach distance of the forward illumination light is adjusted to an optimal distance. The vehicle control section 302 also provides similar information to the headlamp unit 210L, and an illumination control section 228L (control device) provided in the headlamp unit 210L executes the same control as the illumination control section 228R.

[0035] In this embodiment, the light distribution pattern formed by the headlamp units 210L, 210R can be switched depending on the operation of the light switch 304 by the driver. In this case, depending on the operation of the light switch 304, the irradiation control units 228L, 228R control the motor 238 via the variable shade control unit 232 to determine the light distribution pattern formed by the lamp unit 10.

[0036] The headlamp units 210L, 210R of this embodiment may be automatically controlled to detect the situation around the vehicle using various sensors and form a light distribution pattern optimal for the state of the vehicle 300 and the situation around the vehicle, regardless of the operation of the light switch 304. For example, when it is detected that a preceding vehicle, an oncoming vehicle, a pedestrian, or the like exists ahead of the vehicle, the irradiation control units 228L, 228R determine that glare should be prevented based on information obtained from the vehicle control unit 302, and form a light distribution pattern for low beam by the lamp unit 10. When it is detected that a preceding vehicle, an oncoming vehicle, a pedestrian, or the like does not exist ahead of the vehicle, the irradiation control units 228L, 228R determine that the driver's visibility should be improved, and form a light distribution pattern for high beam without shading by the rotating shade 12. In addition to the low beam light distribution pattern and the high beam light distribution pattern, when a conventionally known special high beam light distribution pattern or special low beam light distribution pattern such as a so-called left or right one-sided high beam light distribution pattern or a V beam light distribution pattern can be formed, an optimal light distribution pattern may be formed taking into account the presence of a vehicle ahead according to the presence of a vehicle ahead. Such a control mode is sometimes called an ADB (Adaptive Driving Beam) mode.

[0037] In order to detect objects such as a preceding vehicle or an oncoming vehicle, a camera 305 such as a stereo camera is connected to the vehicle control unit 302 as a recognition means for the object. The image frame data captured by the camera 305 is subjected to predetermined image processing such as object recognition processing by the image processing unit 308, and the recognition result is provided to the vehicle control unit 302. For example, if the recognition result data provided from the image processing unit 308 includes data including a feature point indicating a vehicle previously stored by the vehicle control unit 302, the vehicle control unit 302 recognizes the presence of the vehicle and provides the information to the irradiation control units 228L and 228R. The irradiation control units 228L and 228R receive vehicle information from the vehicle control unit 302, determine an optimal light distribution pattern taking the vehicle into consideration, and form the light distribution pattern. Here, the "feature point indicating a vehicle" is, for example, a light point with a predetermined luminous intensity or more that appears in an estimated presence area of ​​a headlight of a preceding vehicle or a marker light such as a tail lamp. Furthermore, for example, when the recognition result data provided from the image processing unit 308 contains data including pre-stored feature points indicating a pedestrian, the vehicle control unit 302 provides the information to the illumination control units 228L, 228R, and the illumination control units 228L, 228R form an optimal light distribution pattern taking the pedestrian into consideration.

[0038] The vehicle control unit 302 can also obtain information from a steering sensor 310, a vehicle speed sensor 312, a navigation system 314, an acceleration sensor 316 as an inclination detection device, and the like mounted on the vehicle 300. This allows the illumination control units 228L, 228R to select a light distribution pattern to be formed according to the running state and attitude of the vehicle 300, or to change the direction of the optical axis O to simply change the light distribution pattern. For example, when there is luggage in the luggage compartment at the rear of the vehicle or there is a passenger in the rear seat, the vehicle attitude is inclined backward, and when the luggage is unloaded or the passenger in the rear seat gets off, the vehicle attitude is inclined forward from the backward inclination state. The illumination direction of the lamp unit 10 also changes up and down according to the attitude state of the vehicle 300, and the forward illumination distance becomes longer or shorter. Therefore, the illumination control units 228L and 228R receive the inclination angle of the vehicle 300 from the acceleration sensor 316 via the vehicle control unit 302, and control the leveling actuator 226 via the leveling control unit 236 to set the pitch angle of the optical axis O to an angle according to the vehicle attitude. In this way, by performing the leveling adjustment of the lamp unit 10 in real time based on the vehicle attitude, the reach distance of the forward illumination can be optimally adjusted even if the vehicle attitude changes according to the usage situation of the vehicle 300. Such a control mode may be called an auto-leveling control mode. The automatic formation control of the light distribution pattern including the various control modes described above is executed when the automatic formation control of the light distribution pattern is instructed by the light switch 304, for example.

[0039] In this embodiment, the acceleration sensor 316 is used as an example of an inclination detection device for detecting the inclination angle of the vehicle 300 relative to the horizontal plane. However, the inclination detection device is not limited to the acceleration sensor 316, and other sensors such as a gyro sensor or a geomagnetic sensor may be used.

[0040] Next, the auto-leveling control by the vehicle lighting system 200 having the above-mentioned configuration will be described in detail.

[0041] The acceleration sensor 316 of the vehicle lighting system 200 according to this embodiment is a three-axis acceleration sensor having, for example, an X-axis, a Y-axis, and a Z-axis that are mutually orthogonal. The acceleration sensor 316 is attached to the vehicle 300 so that the X-axis of the sensor is along the front-rear axis of the vehicle 300, the Y-axis of the sensor is along the left-right axis of the vehicle 300, and the Z-axis of the sensor is along the up-down axis of the vehicle 300. The acceleration sensor 316 can detect a resultant acceleration vector obtained by combining a gravitational acceleration vector and a motion acceleration vector generated by the movement of the vehicle 300, and outputs the numerical value of each component of the resultant acceleration vector in the three axial directions. When the vehicle 300 is in a stationary state, the acceleration sensor 316 outputs the numerical value of each component of the gravitational acceleration vector in the three axial directions. That is, the acceleration sensor 316 can detect the inclination angle (total angle) of the vehicle with respect to the horizontal plane as a vector, which includes the inclination angle (first angle) of the road surface with respect to the horizontal plane and the inclination angle (second angle) of the vehicle with respect to the road surface. In other words, the inclination angle of the vehicle with respect to the horizontal plane can be derived from the detection value of the acceleration sensor 316. Hereinafter, the inclination angle of the road surface with respect to the horizontal plane will be referred to as the "road surface angle" and given the symbol θr, the inclination angle of the vehicle with respect to the road surface will be referred to as the "vehicle attitude angle" and given the symbol θv, and the inclination angle of the vehicle with respect to the horizontal plane will be referred to as the "total angle" and given the symbol θ. Note that the road surface angle θr, the vehicle attitude angle θv, and the total angle θ are each the angle in the up-down direction of the X-axis, in other words, the angle in the pitch direction of the vehicle 300.

[0042] The acceleration sensor 316 may be attached to the vehicle 300 in any orientation. In this case, the numerical values ​​of the components of the X-axis, Y-axis, and Z-axis output from the acceleration sensor 316 are converted by the irradiation control unit 228R into the components of the front-rear axis, left-right axis, and up-down axis of the vehicle, and the total angle θ is derived. Here, when the acceleration sensor 316 is used as the inclination detection device, it is naturally understood that the irradiation control unit 228R receives the numerical values ​​of each axis component of the acceleration vector from the acceleration sensor 316 and derives the total angle θ from the numerical values ​​of each axis component, which is included in "receiving the total angle from the inclination detection device". In this case, for example, the inclination detection device may be configured by the acceleration sensor 316 and a total angle calculation unit (not shown) included in the irradiation control unit 228R. Also, the detection value of the inclination detection device may be the total angle θ derived from the detection value of the acceleration sensor 316.

[0043] Here, the auto-leveling control is intended to absorb the change in the forward illumination distance of the vehicle lamp accompanying the change in the vehicle inclination angle, and to maintain the forward reach distance of the illumination light at an optimum value. Therefore, the vehicle inclination angle required for the auto-leveling control is the vehicle attitude angle θv. Therefore, the vehicle lighting system 200 according to this embodiment adjusts the optical axis position of the lighting unit 10 when the vehicle attitude angle θv changes, and controls to maintain the optical axis position of the lighting unit 10 when the road surface angle θr changes.

[0044] In addition, in this embodiment, the change in the total angle θ while the vehicle is stopped is estimated as the change in the vehicle attitude angle θv, and the change in the total angle θ while the vehicle is traveling is estimated as the change in the road surface angle θr. That is, while traveling, the vehicle attitude angle θv rarely changes due to an increase or decrease in the load amount or the number of passengers, so the change in the total angle θ while traveling can be estimated as the change in the road surface angle θr. On the other hand, while the vehicle is stopped, the vehicle 300 rarely moves and the road surface angle θr rarely changes, so the change in the total angle θ while the vehicle is stopped can be estimated as the change in the vehicle attitude angle θv. The illumination control unit 228R derives the total angle θ from the detection value of the acceleration sensor 316, generates a control signal that instructs the adjustment of the optical axis position in response to a change in the total angle θ while the vehicle is stopped, and avoids the generation of the control signal in response to a change in the total angle θ while the vehicle is traveling. Then, the control signal is transmitted to the leveling control unit 236. The illumination control unit 228R may generate a control signal that instructs the maintenance of the optical axis position in response to changes in the total angle θ while the vehicle is traveling, and transmit this control signal to the leveling control unit 236.

[0045] Specifically, first, the vehicle 300 is placed on a horizontal plane to be in a reference state, for example, at a vehicle manufacturer's manufacturing plant or a dealer's maintenance plant. In the reference state, the vehicle 300 is in a state in which one person is seated in the driver's seat, or in an empty vehicle state. Then, an initialization signal is transmitted to the irradiation control unit 228R by operating a switch of an initialization processing device in the factory, or by communication of a CAN (Controller Area Network) system that connects the irradiation control unit 228R and the acceleration sensor 316 via the vehicle control unit 302. The initialization signal transmitted to the irradiation control unit 228R is received by the receiving unit 228R1 and transmitted to the control unit 228R2. When the control unit 228R2 receives the initialization signal, it performs an initial aiming adjustment using the output value of the acceleration sensor 316 received by the receiving unit 228R1 as a reference tilt angle. In addition, the control unit 228R2 records information that the reference value of the road surface angle θr=0° and the reference value of the vehicle attitude angle θv=0° in the memory 228R4, thereby holding these reference values.

[0046] While the vehicle is traveling, the control unit 228R2 (illumination control unit 228R) avoids generating a control signal that instructs adjustment of the optical axis position. Whether the vehicle 300 is traveling can be determined, for example, by the vehicle speed obtained from the vehicle speed sensor 312. The aforementioned "vehicle is traveling" refers to the period from when the detection value of the vehicle speed sensor 312 exceeds 0 to when the detection value of the vehicle speed sensor 312 becomes 0 again, for example. This "vehicle is traveling" can be appropriately set by the designer based on experiments and simulations.

[0047] When the vehicle stops, the control unit 228R2 subtracts the reference value of the vehicle attitude angle θv read from the memory 228R4 from the current inclination angle of the vehicle 300 derived from the detection value of the acceleration sensor 316, that is, the total angle θ, to calculate the road surface angle θr when the vehicle stops. Then, this road surface angle θr is recorded in the memory 228R4 as a new reference value of the road surface angle θr. The "when the vehicle stops" is, for example, when the detection value of the acceleration sensor 316 becomes stable after the detection value of the vehicle speed sensor 312 becomes 0. The reason why the detection value of the acceleration sensor 316 becomes stable is because it takes some time for the vehicle attitude to become stable after the vehicle 300 stops, and it is difficult to detect the accurate total angle θ when the vehicle attitude is not stable. This "when it becomes stable" may be when the change amount per unit time of the detection value of the acceleration sensor 316 becomes a predetermined amount or less, or may be when a predetermined time has passed since the detection value of the vehicle speed sensor 312 became 0. The "when the vehicle is stopped," "predetermined amount," and "predetermined time" can be appropriately set by a designer based on experiments and simulations.

[0048] In addition, the control unit 228R2 may record the calculated road surface angle θr in the memory 228R4 as a new reference value when the difference between the road surface angle θr when the vehicle is stopped, which is obtained by subtracting the reference value of the vehicle attitude angle θv from the total angle θ when the vehicle is stopped, and the reference value of the road surface angle θr recorded in the memory 228R4 is equal to or greater than a predetermined amount. In addition, the control unit 228R2 may calculate the road surface angle θr when the total angle θ when the vehicle 300 starts and the total angle θ when the vehicle is stopped are different. In this way, it is possible to avoid frequent rewriting of the reference value of the road surface angle θr, and it is possible to reduce the control load of the control unit 228R2.

[0049] While the vehicle is stopped, the control unit 228R2 repeatedly calculates the vehicle attitude angle θv at a predetermined timing. The vehicle attitude angle θv is obtained by subtracting the reference value of the road surface angle θr recorded in the memory 228R4 from the current total angle θ. If the difference between the calculated vehicle attitude angle θv and the reference value of the vehicle attitude angle θv is equal to or greater than a predetermined amount, the control unit 228R2 generates a control signal for adjusting the optical axis based on the newly obtained vehicle attitude angle θv. Then, the optical axis is adjusted based on this control signal. In addition, the calculated vehicle attitude angle θv is recorded in the memory 228R4 as a new reference value. In this way, frequent optical axis adjustment can be avoided by performing the optical axis adjustment when the difference between the calculated vehicle attitude angle θv and the reference value is equal to or greater than a predetermined amount. As a result, the control burden of the control unit 228R2 can be reduced, and the life of the leveling actuator 226 can be extended. The "vehicle is stopped" is, for example, from when the detection value of the acceleration sensor 316 becomes stable until the vehicle starts, and this "vehicle starts" is, for example, when the detection value of the vehicle speed sensor 312 exceeds 0. Note that the calculation of the vehicle attitude angle θv may be performed when the vehicle starts, rather than being repeatedly performed at a predetermined timing. The "vehicle is stopped" can be appropriately set based on experiments and simulations by the designer.

[0050] Also, for example, in a configuration in which power is not supplied to the irradiation control unit 228R when the ignition (IG) is off and the memory 228R4 is not a non-volatile memory, the control unit 228R2 records the reference value of the road surface angle θr in a non-volatile memory (not shown) when it receives an IG-OFF signal sent from the vehicle control unit 302 when the ignition is off or when the power supply voltage supplied to the irradiation control unit 228R becomes equal to or lower than a predetermined value. This allows the reference value of the road surface angle θr to be held even when the ignition is off, so that the auto-leveling control can be performed with high accuracy even after the ignition is on.

[0051] Furthermore, when the ignition is turned on, that is, when the illumination control unit 228R is started, the control unit 228R2 calculates the vehicle attitude angle θv from the detection value of the acceleration sensor 316 and the reference value of the road surface angle θr. Then, the control unit 228R2 determines the optical axis position using the calculated vehicle attitude angle θv, and stores the calculated vehicle attitude angle θv as a new reference value by recording it in the memory 228R4. As a result, even if the vehicle attitude angle θv changes while the ignition is off, the optical axis O is adjusted to an appropriate position when the ignition is on, thereby improving the accuracy of the auto-leveling control.

[0052] Alternatively, in a configuration in which power is not supplied to the illumination control unit 228R when the ignition is turned off and the memory 228R4 is not a non-volatile memory, the control unit 228R2 records in the non-volatile memory when the ignition is turned off the reference value of the vehicle attitude angle θv and the detection value or total angle θ of the acceleration sensor 316 last detected before the ignition is turned off, i.e., the detection value or total angle θ of the acceleration sensor 316 last detected during the previous driving (period from ignition on to ignition off). Then, when the illumination control unit 228R is started, the control unit 228R2 calculates the difference between the total angle θ obtained from the current detection value of the acceleration sensor 316 and the total angle θ obtained from the detection value of the acceleration sensor 316 last detected before the ignition is turned off, and calculates the current vehicle attitude angle θv from the obtained difference and the reference value of the vehicle attitude angle θv. Then, the control unit 228R2 performs the optical axis adjustment using the calculated vehicle attitude angle θv, and records the calculated vehicle attitude angle θv in the memory 228R4 as a new reference value. In this case, the optical axis adjustment corresponding to the change in the vehicle attitude angle θv while the ignition is off is also possible, so that the accuracy of the auto-leveling control can be improved.

[0053] In the above-described control, the road surface angle θr is calculated by subtracting the reference value of the vehicle attitude angle θv from the total angle θ, and the obtained road surface angle θr is held as a new reference value. However, by holding the total angle θ and the reference value of the vehicle attitude angle θv used in this calculation, the road surface angle θr is essentially held as a new reference value. Therefore, holding the road surface angle θr as a new reference value in this embodiment also includes holding such reference values ​​of the total angle θ and the vehicle attitude angle θv used in the calculation. The same is true for the calculation of the vehicle attitude angle θv, and holding the vehicle attitude angle θv as a new reference value in this embodiment includes holding the total angle θ and the reference value of the road surface angle θr used in the calculation. In this case, the held total angle θ may be the detection value of the acceleration sensor 316 corresponding to this total angle θ.

[0054] FIG. 3 is an auto-leveling control flowchart of the vehicle lighting system according to the first embodiment. In the flowchart of FIG. 3, the processing procedure of each unit is displayed by a combination of S (initial letter of Step), which means a step, and a number. In addition, in the process displayed by the combination of S and a number, if some judgment process is performed and the judgment result is positive, Y (initial letter of Yes) is added and displayed as (Y of S101), for example, and conversely, if the judgment result is negative, N (initial letter of No) is added and displayed as (N of S101), for example. This flow is repeatedly executed at a predetermined timing by the illumination control unit 228R (control unit 228R2) when the ignition is turned on in a state in which the execution instruction of the auto-leveling control mode is given by the light switch 304, and ends when the ignition is turned off.

[0055] First, the control unit 228R2 judges whether the vehicle is traveling (S101). If the vehicle is traveling (Y in S101), the control unit 228R2 does not generate a control signal instructing adjustment of the optical axis position, avoids optical axis adjustment (S102), and ends this routine. If the vehicle is not traveling (N in S101), the control unit 228R2 judges whether the vehicle is stopped (S103). If the vehicle is stopped (Y in S103), the control unit 228R2 subtracts the reference value of the vehicle attitude angle θv from the current total angle θ to calculate the road surface angle θr (S104), and records the calculated road surface angle θr in the memory 228R4 as a new reference value. Then, the illumination control unit 228R avoids optical axis adjustment (S102), and ends this routine.

[0056] If the vehicle is not stopped (N in S103), this means that the vehicle is stopped, so the control unit 228R2 calculates the vehicle attitude angle θv by subtracting the reference value of the road surface angle θr from the current total angle θ (S106). Next, the control unit 228R2 determines whether the difference between the calculated vehicle attitude angle θv and the reference value of the vehicle attitude angle θv is equal to or greater than a predetermined amount (S107). If the difference is less than the predetermined amount (N in S107), the control unit 228R2 avoids adjusting the optical axis (S102) and ends this routine. If the difference is equal to or greater than the predetermined amount (Y in S107), the control unit 228R2 adjusts the optical axis position based on the calculated vehicle attitude angle θv (S108). Then, the control unit 228R2 records the calculated vehicle attitude angle θv as a reference value in the memory 228R4 (S109) and ends this routine.

[0057] For the left headlamp unit 210L, the illumination control unit 228L (control unit 228L2) executes similar control. Alternatively, one of the illumination control units 228L, 228R may calculate the vehicle attitude angle θv or the road surface angle θr, and the other may obtain the calculated vehicle attitude angle θv or the road surface angle θr and adjust the optical axis O.

[0058] As described above, in the vehicle lighting system 200 according to this embodiment, when the illumination control units 228L and 228R perform auto-leveling control based on the total angle θ derived from the detection value of the acceleration sensor 316, the illumination control units 228L and 228R adjust the optical axis position when the vehicle attitude angle θv changes, and maintain the optical axis position when the road surface angle θr changes. In addition, in this embodiment, the change in the total angle θ while the vehicle is stopped is estimated as the change in the vehicle attitude angle θv, and the change in the total angle θ while the vehicle is traveling is estimated as the change in the road surface angle θr. Then, the illumination control units 228L and 228R generate a control signal that instructs the adjustment of the optical axis position in response to the change in the total angle θ while the vehicle is stopped, and generate a control signal that avoids the generation of the control signal or instructs the maintenance of the optical axis position in response to the change in the total angle θ while the vehicle is traveling. That is, when the total angle θ changes while the vehicle is stopped, the illumination control units 228L and 228R generate a control signal that instructs the adjustment of the optical axis, regarding the change in the total angle θ as the change in the vehicle attitude angle θv. This allows for more accurate auto-leveling control using an inclination detection device that detects the inclination angle of the vehicle 300 relative to the horizontal plane. In this embodiment, the inclination angle of the vehicle 300 is detected using an inclination detection device such as the acceleration sensor 316, so there is no need to use a vehicle height sensor. This is therefore more advantageous in terms of cost reduction than using a vehicle height sensor, and also provides greater freedom in vehicle body design.

[0059] (Embodiment 2) The vehicle lighting system 200 according to the second embodiment performs auto-leveling control in consideration of changes in the vehicle attitude angle θv that may occur during vehicle travel. This embodiment will be described below. Note that the main configuration of the vehicle lighting system 200, the main flow of the auto-leveling control, and the shape of the light distribution pattern that can be formed are the same as those of the first embodiment, so the same reference numerals are used for the same configurations as those of the first embodiment, and the description and illustration thereof will be omitted as appropriate. FIG. 4 is an explanatory diagram of the auto-leveling control by the vehicle lighting system according to the second embodiment.

[0060] In the first embodiment, the change in the vehicle inclination angle (total angle θ) during vehicle travel is estimated as the change in the road surface angle θr. This allows the auto-leveling control to be performed with high accuracy using a simple control structure. However, although rare, there are cases where the vehicle attitude angle θv changes during vehicle travel. For example, if the vehicle 300 is a large vehicle such as a bus, there is a possibility that an occupant moves within the vehicle cabin while the vehicle is traveling, which may cause the vehicle attitude angle θv to change. Therefore, if the change in the total angle θ during vehicle travel is estimated as the change in the road surface angle θr, an error may occur between the actual road surface angle θr and the estimated road surface angle θr.

[0061] Therefore, in this embodiment, a road surface level determination is performed at least when the vehicle starts or stops, and the reference value of the road surface angle θr is corrected according to the result of the road surface level determination.

[0062] The road surface horizontality determination and the reference value correction according to the result when the vehicle starts are performed as follows. First, the control unit 228R2 determines whether the vehicle 300 has started. The control unit 228R2 can determine that the vehicle 300 has started when the vehicle speed change amount (motion acceleration of the vehicle 300) per unit time obtained from the detection value of the vehicle speed sensor 312 is equal to or greater than a predetermined value. The predetermined value of the motion acceleration at which it is determined that the vehicle 300 has started can be set appropriately. The control unit 228R2 also determines whether the vehicle 300 is moving straight. The control unit 228R2 can determine that the vehicle is moving straight from the detection value of the steering sensor 310 or the value of the Y-axis component of the acceleration sensor 316. For example, the control unit 228R2 determines that the vehicle 300 is moving straight when the steering wheel angle is near 0° from the detection value of the steering sensor 310. The range of the steering angle at which it is determined that the vehicle 300 is moving straight can be set appropriately.

[0063] When the vehicle 300 is moving straight, the control unit 228R2 calculates the square of the magnitude of the motion acceleration vector of the vehicle 300 obtained from the vehicle speed sensor 312 or the acceleration sensor 316 a predetermined time after the vehicle starts, and the square of the magnitude of the detection value vector of the acceleration sensor 316. Then, when the difference is equal to the square of the magnitude of the gravitational acceleration vector, the control unit 228R2 corrects the reference value of the road surface angle θr held so as to approach 0°.

[0064] Furthermore, the road surface level determination when the vehicle stops and the reference value correction according to the result are performed as follows. First, the control unit 228R2 determines whether the vehicle is predicted to stop. The control unit 228R2 can predict that the vehicle 300 will stop if the amount of change in vehicle speed per unit time (the motion deceleration of the vehicle 300, i.e., the negative motion acceleration) obtained from the detection value of the vehicle speed sensor 312 is equal to or greater than a predetermined value. The predetermined value of the motion deceleration at which the vehicle 300 is predicted to stop can be set appropriately. Furthermore, the control unit 228R2 determines whether the vehicle 300 is moving straight.

[0065] When the vehicle 300 is traveling straight and then the vehicle speed becomes 0 and the vehicle 300 stops, the control unit 228R2 calculates the square of the magnitude of the motion acceleration vector of the vehicle 300 obtained from the vehicle speed sensor 312 or the acceleration sensor 316 a predetermined time before the vehicle stopped, and the square of the magnitude of the detection value vector of the acceleration sensor 316. Then, when the difference is equal to the square of the magnitude of the gravitational acceleration vector, the control unit 228R2 corrects the reference value of the road surface angle θr obtained when the vehicle stopped so that it approaches 0°.

[0066] As shown in Fig. 4, for example, when vehicle 300, whose pitch angle is tilted by vehicle attitude angle θv, stops on a road with road surface angle θr, vehicle 300 is subjected to gravitational acceleration of magnitude G and motion acceleration (motion deceleration) of magnitude α in the direction in which vehicle 300 decelerates. This motion acceleration is a vector parallel to the road surface. Therefore, the X-axis component, Y-axis component, and Z-axis component of detection value vector V = (x, y, z) of acceleration sensor 316 in this state can be expressed by the following equations (1) to (3).

[0067]

number

[0068] The square of the magnitude of the detection value vector V of the acceleration sensor 316 is expressed by the following equation (4).

[0069]

number

[0070] Here, the above formula (4) is transformed to obtain the following formula (5).

[0071]

number

[0072] When the vehicle 300 stops on a horizontal road, that is, when the road surface angle θr=0°, it can be seen from the above formula (5) that the difference between the square of the magnitude of the detection value vector V of the acceleration sensor 316 and the square of the magnitude α of the motion acceleration vector is equal to the square of the magnitude G of the gravitational acceleration vector. Therefore, by calculating the square of the magnitude α of the motion acceleration vector of the vehicle 300 obtained from the vehicle speed sensor 312 or the acceleration sensor 316 and the square of the magnitude of the detection value vector V of the acceleration sensor 316 and judging whether or not the difference is equal to the square of the magnitude G of the gravitational acceleration vector, it is possible to judge whether or not the vehicle 300 is on a horizontal plane. Therefore, when the difference between the square of the magnitude of the motion acceleration vector and the square of the magnitude of the detection value vector a predetermined time before the vehicle stops is equal to the square of the magnitude of the gravitational acceleration vector, the control unit 228R2 executes a correction to bring the reference value of the road surface angle θr obtained when the vehicle stops closer to 0°. The correction amount can be, for example, in the range of 0.01° to 0.1°.

[0073] Also, when the vehicle starts, the detection value vector, the motion acceleration vector, and the gravity acceleration vector of the acceleration sensor 316 have the same relationship as when the vehicle stops. Therefore, when the difference between the square of the magnitude of the motion acceleration vector and the square of the magnitude of the detection value vector after a predetermined time from the vehicle starting is equal to the square of the magnitude of the gravity acceleration vector, the control unit 228R2 executes a correction to bring the reference value of the road surface angle θr held closer to 0°. By performing the above-mentioned correction either when the vehicle starts or when the vehicle stops, the accuracy of the auto-leveling control can be improved while suppressing an increase in the control load of the control unit 228R2. Also, when the correction is performed both when the vehicle starts and when the vehicle stops, the accuracy of the auto-leveling control can be further improved.

[0074] The "predetermined time after the vehicle starts" and "predetermined time before the vehicle stops" are times when the above-mentioned horizontal determination can be performed on a road surface whose road surface angle θr is substantially equal to the road surface at the point where the reference value of the road surface angle θr to be corrected is calculated. That is, when the vehicle starts, the horizontal determination can be performed on the road surface immediately after the start, so that the horizontality of the road surface on which the reference value of the road surface angle θr to be corrected is calculated can be substantially determined. When the vehicle stops, the horizontality determination can be performed on the road surface immediately before the stop, so that the horizontality of the road surface on which the reference value of the road surface angle θr to be corrected is calculated can be substantially determined. Then, if the result of the determination is that the road surface is horizontal but the reference value of the road surface angle θr is not 0°, this means that there is an error between the actual road surface angle θr and the recorded reference value of the road surface angle θr, so the reference value is corrected to approach 0°.

[0075] As a result, even if the vehicle attitude angle θv changes while the vehicle is traveling, a reference value of the road surface angle θr that takes the change into consideration can be obtained. Since the vehicle attitude angle θv is calculated using the corrected reference value of the road surface angle θr, the vehicle attitude angle θv can be calculated more accurately. The "predetermined time after the vehicle starts" and "predetermined time before the vehicle stops" can be appropriately set based on experiments and simulations by a designer. In addition, the road surface may be determined to be horizontal when a state in which the difference between the square of the magnitude of the motion acceleration vector and the square of the magnitude of the detection value vector is equal to the square of the magnitude of the gravitational acceleration vector continues for a predetermined time, for example, 3 seconds or more.

[0076] 5 is a control flowchart of road surface horizontality determination and road surface angle correction when the vehicle starts in the vehicle lighting system according to the embodiment 2. This flow is repeatedly executed at a predetermined timing by the control unit 228R2 (illumination control unit 228R) when the ignition is turned on in a state where the execution instruction of the auto-leveling control mode is given by the light switch 304, for example, and ends when the ignition is turned off. This flow is also appropriately incorporated into the control flow of the embodiment 1.

[0077] First, the control unit 228R2 determines whether the vehicle is stopped (S201). If the vehicle is not stopped (N in S201), the control unit 228R2 ends this routine. If the vehicle is stopped (Y in S201), the control unit 228R2 determines whether the motion acceleration of the vehicle 300 is equal to or greater than a predetermined value (S202). That is, the control unit 228R2 determines whether the vehicle 300 has started moving. If the motion acceleration is less than the predetermined value (N in S202), the control unit 228R2 repeatedly determines whether the motion acceleration of the vehicle 300 is equal to or greater than a predetermined value (S202). If the motion acceleration is equal to or greater than a predetermined value (Y in S202), the control unit 228R2 determines whether the steering angle is near 0° (S203).

[0078] If the steering angle is not near 0° (N in S203), the control unit 228R2 ends this routine. If the steering angle is near 0° (Y in S203), the control unit 228R2 performs a road surface horizontality determination (S204). Then, the control unit 228R2 determines whether the road surface is horizontal (S205). If the road surface is not horizontal (N in S205), the control unit 228R2 ends this routine. If the road surface is horizontal (Y in S205), the control unit 228R2 corrects the reference value of the road surface angle θr to approach 0° (S206), and ends this routine.

[0079] 6 is a control flowchart of road surface horizontality determination and road surface angle correction when the vehicle stops in the vehicle lighting system according to the second embodiment. This flow is repeatedly executed at a predetermined timing by the control unit 228R2 (illumination control unit 228R) when the ignition is turned on in a state where the execution instruction of the auto-leveling control mode is given by the light switch 304, for example, and ends when the ignition is turned off. This flow is also appropriately incorporated into the control flow of the first embodiment.

[0080] First, the control unit 228R2 determines whether the vehicle is moving (S301). If the vehicle is not moving (N in S301), the control unit 228R2 ends this routine. If the vehicle is moving (Y in S301), the control unit 228R2 determines whether the motion deceleration of the vehicle 300 is equal to or greater than a predetermined value (S302). If the motion deceleration is less than the predetermined value (N in S302), the control unit 228R2 ends this routine. If the motion deceleration is equal to or greater than the predetermined value (Y in S302), the control unit 228R2 determines whether the steering wheel angle is near 0° (S303).

[0081] If the steering angle is not near 0° (N in S303), the control unit 228R2 ends this routine. If the steering angle is near 0° (Y in S303), the control unit 228R2 determines whether the vehicle speed is 0 from the detection value of the vehicle speed sensor 312 (S304). If the vehicle speed is not 0 (N in S304), the control unit 228R2 ends this routine. If the vehicle speed is 0 (Y in S304), the control unit 228R2 performs a road surface horizontality determination (S305) and determines whether the road surface is horizontal (S306). If the road surface is not horizontal (N in S306), the control unit 228R2 ends this routine. If the road surface is horizontal (Y in S306), the control unit 228R2 corrects the reference value of the road surface angle θr to approach 0° (S307) and ends this routine.

[0082] As described above, in the vehicle lighting system 200 according to this embodiment, the illumination control units 228L and 228R perform a road surface horizontality determination at least when the vehicle starts or stops, and correct the reference value of the road surface angle θr according to the result. Therefore, even if the vehicle attitude angle θv changes while the vehicle is traveling, the reference value of the road surface angle θr that takes the change into consideration can be obtained, and the accuracy of the auto-leveling control can be further improved.

[0083] (Embodiment 3) The vehicle lighting system 200 according to the third embodiment considers the change in road surface angle θr that may occur while the vehicle is stopped in the auto-leveling control. Hereinafter, this embodiment will be described. Note that the main configuration of the vehicle lighting system 200, the main flow of the auto-leveling control, and the shape of the light distribution pattern that can be formed are the same as those in the first embodiment, so the same reference numerals are used for the same configurations as those in the first embodiment, and the description and illustration thereof will be omitted as appropriate.

[0084] In the first embodiment, the change in the vehicle inclination angle (total angle θ) while the vehicle is stopped is estimated as the change in the vehicle attitude angle θv. This allows the auto-leveling control to be performed with high accuracy using a simple control structure. However, although rare, there are cases where the road surface angle θr changes while the vehicle is stopped. For example, when the vehicle 300 is transported or towed by a ship, a car carrier, or the like, the road surface angle θr may change while the vehicle is stopped. Therefore, when the change in the total angle θ while the vehicle is traveling is estimated as the change in the vehicle attitude angle θv, an error may occur between the actual vehicle attitude angle θv and the estimated vehicle attitude angle θv.

[0085] Therefore, in this embodiment, it is determined whether the vehicle attitude angle θv obtained from the total angle θ and the reference value of the road surface angle θr is within a predetermined range, and depending on the determination result, the auto-leveling control is performed or the auto-leveling control is stopped.

[0086] When the vehicle attitude angle θv obtained from the total angle θ derived from the detection value of the acceleration sensor 316 and the reference value of the road surface angle θr exceeds a predetermined range, the control unit 228R2 determines the optical axis position of the lamp unit 10 using the reference value of the vehicle attitude angle θv held. When the calculated vehicle attitude angle θv is included in the predetermined range, the control unit 228R2 determines the optical axis position using the calculated vehicle attitude angle θv. This makes it possible to improve the visibility of the driver of the vehicle while reducing the risk of giving glare to the driver of another vehicle. The "predetermined range" is, for example, a range from the vehicle attitude angle θv in an empty state to the vehicle attitude angle θv in a state where the maximum load is applied to the luggage compartment, that is, a range of the vehicle attitude angle θv that the vehicle 300 can substantially take, with a margin of 0.1° added. When the calculated vehicle attitude angle θv exceeds this range, it can be estimated that the calculated vehicle attitude angle θv is different from the actual vehicle attitude angle θv.

[0087] The control unit 228R2 may prohibit the generation of a control signal instructing the adjustment of the optical axis position thereafter when the calculated vehicle attitude angle θv exceeds a predetermined range. Specifically, the control unit 228R2 stops the generation of the control signal (stop of auto-leveling control) when the calculated vehicle attitude angle θv exceeds a predetermined range. Then, the control unit 228R2 turns on an indicator (not shown) via the vehicle control unit 302 to notify the user of an abnormality in the auto-leveling control. The control unit 228R2 also generates auto-leveling control stop information and records it in the memory 228R4. After that, even if an instruction to execute the auto-leveling control is given by operating the light switch 304 or the like, the control unit 228R2 avoids the execution of the auto-leveling control and turns on the indicator when the auto-leveling control stop information is read from the memory 228R4. When the control unit 228R2 receives a reset signal transmitted to the irradiation control unit 228R by a switch operation at a dealer's maintenance shop or by communication of the CAN system, the control unit 228R2 resets the reference value of the vehicle attitude angle θv and the reference value of the road surface angle θr to 0°. In addition, the control unit 228R2 erases or invalidates the auto-leveling control stop information, and restores the auto-leveling control to an executable state. This makes it possible to more reliably prevent glare from being given to drivers of other vehicles.

[0088] Also, for example, in a configuration in which power is not supplied to the irradiation control unit 228R when the ignition is turned off and the memory 228R4 is not a non-volatile memory, the control unit 228R2 records the reference value of the vehicle attitude angle θv in addition to the reference value of the road surface angle θr in a non-volatile memory (not shown) when it receives an IG-OFF signal sent from the vehicle control unit 302 when the ignition is turned off or when the power supply voltage supplied to the irradiation control unit 228R becomes equal to or lower than a predetermined value. This makes it possible to hold the reference value of the vehicle attitude angle θv even when the ignition is turned off.

[0089] The transportation and towing of the vehicle 300 by the above-mentioned ship, car carrier, etc. is often performed with the ignition turned off. Therefore, the control unit 228R2 may determine whether the vehicle attitude angle θv calculated when the ignition is turned on is within a predetermined range, and execute the above-mentioned control based on the determination result.

[0090] 7 is a flow chart of the determination control of the vehicle attitude angle θv in the vehicle lighting system according to the embodiment 3. This flow is repeatedly executed at a predetermined timing by the control unit 228R2 (illumination control unit 228R) when the ignition is turned on in a state where the execution instruction of the auto-leveling control mode is given by the light switch 304, for example, and ends when the ignition is turned off. This flow is also appropriately incorporated into the control flow of the embodiment 1.

[0091] First, the control unit 228R2 calculates the vehicle attitude angle θv from the total angle θ and the reference value of the road surface angle θr (S401), and judges whether the calculated vehicle attitude angle θv is outside a predetermined range (S402). If the calculated vehicle attitude angle θv is outside the predetermined range (Y in S402), the control unit 228R2 performs optical axis adjustment using the recorded reference value of the vehicle attitude angle θv (S403), and ends this routine. If the calculated vehicle attitude angle θv is within the predetermined range (N in S402), the control unit 228R2 performs optical axis adjustment using the calculated vehicle attitude angle θv (S404), and ends this routine.

[0092] 8 is another determination control flowchart of the vehicle attitude angle θv in the vehicle lighting system according to the embodiment 3. This flow is repeatedly executed at a predetermined timing by the control unit 228R2 (illumination control unit 228R) when the ignition is turned on in a state where the execution instruction of the auto-leveling control mode is given by the light switch 304, for example, and ends when the ignition is turned off. This flow is also appropriately incorporated into the control flow of the embodiment 1.

[0093] First, the control unit 228R2 judges whether auto-leveling control stop information is recorded in the memory 228R4 (S501). If there is auto-leveling control stop information (Y in S501), the control unit 228R2 stops the auto-leveling control and turns on the indicator (S502). Next, the control unit 228R2 judges whether a reset signal is detected (S503). If a reset signal is detected (Y in S503), the control unit 228R2 resets the reference value of the vehicle attitude angle θv and the reference value of the road surface angle θr to 0°, erases the auto-leveling control stop information, turns off the indicator (S504), and ends this routine. If a reset signal is not detected (N in S503), this routine ends.

[0094] If there is no auto-leveling control stop information (N in S501), the control unit 228R2 calculates the vehicle attitude angle θv from the total angle θ and the reference value of the road surface angle θr (S505), and judges whether the calculated vehicle attitude angle θv is outside a predetermined range (S506). If the calculated vehicle attitude angle θv is outside the predetermined range (Y in S506), the control unit 228R2 generates auto-leveling control stop information and records it in the memory 228R4 (S507). Then, the control unit 228R2 stops the auto-leveling control and turns on the indicator (S502). Next, the control unit 228R2 performs detection judgment of a reset signal (S503), resets the reference value of the vehicle attitude angle θv and the reference value of the road surface angle θr, erases the auto-leveling control stop information, and controls the indicator to turn off (S504), and ends this routine.

[0095] If the calculated vehicle attitude angle θv is within the predetermined range (N in S506), the control unit 228R2 performs the optical axis adjustment using the calculated vehicle attitude angle θv (S508), and ends this routine.

[0096] As described above, in the vehicle lighting system 200 according to the present embodiment, the illumination control units 228L and 228R determine whether the calculated vehicle attitude angle θv is included in a predetermined range. Then, when the calculated vehicle attitude angle θv is out of the predetermined range, the illumination control units 228L and 228R perform auto-leveling control using the reference value of the vehicle attitude angle θv held. Therefore, even if the road surface angle θr changes while the vehicle is stopped, the auto-leveling control can be performed taking the change into consideration, so that the visibility of the driver of the vehicle can be improved while reducing the glare given to the driver of the other vehicle. Alternatively, when the calculated vehicle attitude angle θv is out of the predetermined range, the illumination control units 228L and 228R stop the auto-leveling control. This can reliably prevent the glare given to the driver of the other vehicle.

[0097] (Embodiment 4) The vehicle lighting system 200 according to the fourth embodiment differs from the first embodiment in the method of auto-leveling control. This embodiment will be described below. Since the configuration of the vehicle lighting system 200 is the same as that of the first embodiment, the same components as those of the first embodiment are given the same reference numerals, and the description and illustration thereof will be omitted as appropriate. Also, as in each of the above-mentioned embodiments, in this embodiment, only the headlamp unit 210R side will be described, and the description of the headlamp unit 210L side will be omitted as appropriate.

[0098] In the auto-leveling control of this embodiment, the vehicle 300 is first placed in the reference state described above. Then, an initialization signal is sent to the irradiation control unit 228R by operating a switch of the initialization processing device or the like. When the control unit 228R2 receives the initialization signal, it starts an initial aiming adjustment and aligns the optical axis O of the lamp unit 10 with the initial setting position. In addition, the control unit 228R2 records the output value of the acceleration sensor 110 when the vehicle 300 is in the reference state in the memory 228R4 as the reference value of the road surface angle θr (θr=0°) and the reference value of the vehicle attitude angle θv (θv=0°).

[0099] In a situation where the vehicle 300 is actually used, the control unit 228R2 avoids the optical axis adjustment in response to a change in the total angle θ while the vehicle is traveling. The control unit 228R2 may avoid the optical axis adjustment by avoiding the output of a control signal instructing the optical axis adjustment, or may avoid the optical axis adjustment by generating a maintenance signal instructing the maintenance of the optical axis position and outputting this maintenance signal. When avoiding the output of a control signal, the output of the control signal may be avoided by not generating the control signal, or the control signal may be generated and then the output of the generated control signal may be avoided.

[0100] Furthermore, the control unit 228R2 updates the reference value of the road surface angle θr by considering the change in the total angle θ while the vehicle is traveling as the change in the road surface angle θr. For example, the control unit 228R2 calculates the difference Δθ1 in the total angle θ before and after traveling when the vehicle is stopped. Then, the control unit 228R2 calculates a new reference value of the road surface angle θr by adding the obtained difference Δθ1 to the reference value of the road surface angle θr recorded in the memory 228R4 (new θr reference value=θr reference value+Δθ1) and records this in the memory 228R4.

[0101] The control unit 228R2 calculates the difference Δθ1, for example, as follows. That is, immediately after the start of the vehicle 300, the control unit 228R2 records the total angle θ immediately before the start in the memory 228R4 as a reference value of the total angle θ. Then, when the vehicle stops, the control unit 228R2 subtracts the reference value of the total angle θ from the current (when the vehicle stops) total angle θ to calculate the difference Δθ1. Note that the control unit 228R2 periodically receives acceleration from the acceleration sensor 316, and holds the acceleration for a predetermined period or the total angle θ obtained from the acceleration. The "immediately after the start" is, for example, a predetermined period from when the detection value of the vehicle speed sensor 312 exceeds 0. The "immediately before the start" is, for example, a time a predetermined time before when the detection value of the vehicle speed sensor 312 exceeds 0. The "immediately after the start" and "immediately before the start" can be appropriately set based on experiments and simulations by a designer.

[0102] During the vehicle stop, the control unit 228R2 updates the reference value of the vehicle attitude angle θv by taking the change in the total angle θ during the vehicle stop as the change in the vehicle attitude angle θv, and generates a control signal for instructing the adjustment of the optical axis position using the reference value of the vehicle attitude angle θv after the update. For example, the control unit 228R2 calculates the difference Δθ2 between the current total angle θ and the reference value of the total angle θ recorded in the memory 228R4 during the vehicle stop. The reference value of the total angle θ used at this time is, for example, the reference value updated after the calculation of the difference Δθ1, that is, the total angle θ at the time of the vehicle stop, in the first calculation of the difference Δθ2 after the vehicle 300 stops, and the reference value updated after the previous calculation of the difference Δθ2 in the second or subsequent calculations. Then, the control unit 228R2 calculates a new reference value of the vehicle attitude angle θv by adding the obtained difference Δθ2 to the reference value of the vehicle attitude angle θv recorded in the memory 228R4 (new θv reference value=θv reference value+Δθ2), and records this in the memory 228R4.

[0103] In addition, the control unit 228R2 may perform optical axis adjustment so as to displace the optical axis O by a difference Δθ2 corresponding to the change in the total angle θ while the vehicle is stopped, without storing the reference value of the road surface angle θr and the reference value of the vehicle attitude angle θv in the memory 228R4.

[0104] 9 is an auto-leveling control flowchart of the vehicle lighting system according to the fourth embodiment. First, the control unit 228R2 judges whether the vehicle is traveling (S601). If the vehicle is traveling (Y in S601), the control unit 228R2 judges whether the vehicle 300 has just started (S602). If the vehicle has just started (Y in S602), the control unit 228R2 records (updates) the total angle θ immediately before starting in the memory 228R4 as the reference value of the total angle θ (S603), avoids the optical axis adjustment (S604), and ends this routine. If the vehicle has not just started (N in S602), the control unit 228R2 avoids the optical axis adjustment without updating the reference value of the total angle θ (S604), and ends this routine.

[0105] If the vehicle is not traveling (N in S601), the control unit 228R2 determines whether the vehicle is stopped (S605). If the vehicle is stopped (Y in S605), the control unit 228R2 subtracts the reference value of the total angle θ from the current total angle θ to calculate a difference Δθ1 (S606). Then, the control unit 228R2 calculates a new reference value of the road surface angle θr from the calculated difference Δθ1 and the reference value of the road surface angle θr recorded in the memory 228R4, and updates the reference value of the road surface angle θr (S607). The control unit 228R2 also records the current total angle θ in the memory 228R4 as the new reference value of the total angle θ (S608), and ends this routine.

[0106] If the vehicle is not stopped (N in S605), this means that the vehicle is stopped, so the control unit 228R2 subtracts the reference value of the total angle θ from the current total angle θ to calculate a difference Δθ2 (S609). The control unit 228R2 calculates a new reference value of the vehicle attitude angle θv from the calculated difference Δθ2 and the reference value of the vehicle attitude angle θv recorded in the memory 228R4, and updates the reference value of the vehicle attitude angle θv (S610). Then, the control unit 228R2 performs optical axis adjustment according to the updated reference value of the vehicle attitude angle θv (S611). The control unit 228R2 also records the current total angle θ in the memory 228R4 as a new reference value of the total angle θ (S612), and ends this routine.

[0107] For the left headlamp unit 210L, the illumination control unit 228L may perform similar control, or one of the illumination control units 228L, 228R may calculate the vehicle attitude angle θv or the road surface angle θr, and the other may obtain the calculated vehicle attitude angle θv or road surface angle θr and adjust the optical axis O.

[0108] As described above, the auto-leveling control of this embodiment can also perform the auto-leveling control with higher accuracy. In addition, in the auto-leveling control of this embodiment, the difference Δθ1, which is the change in the total angle θ while the vehicle is traveling, is added to the reference value of the road surface angle θr to derive a new road surface angle θr, and the difference Δθ2, which is the change in the total angle θ while the vehicle is stopped, is added to the reference value of the vehicle attitude angle θv to derive a new vehicle attitude angle θv. Therefore, it is possible to avoid the accumulation of errors in the reference value of the road surface angle θr and the reference value of the vehicle attitude angle θv, which may occur in the auto-leveling control of the first embodiment.

[0109] The vehicle lighting system 200 according to each embodiment is one aspect of the present invention. The vehicle lighting system 200 includes a lighting unit 10 capable of adjusting an optical axis O, an acceleration sensor 316 (tilt detector) capable of detecting the tilt angle of the vehicle 300 relative to a horizontal plane, and illumination controllers 228L and 228R for controlling the lighting unit 10, and the illumination controllers 228L and 228R execute the above-mentioned auto-leveling control.

[0110] Another aspect of the present invention is the illumination control units 228L and 228R as a control device. The illumination control units 228L and 228R include a receiving unit 228L1 and 228R1 for receiving the inclination angle of the vehicle 300 with respect to the horizontal plane from the inclination detection device, a control unit 228L2 and 228R2 for executing the above-mentioned auto-leveling control, and a transmitting unit 228L3 and 228R3 for transmitting the control signal generated by the control unit 228L2 and 228R2 to the leveling control unit 236. The illumination control unit 228 in the vehicle lighting system 200 corresponds to a control unit in a broad sense, and the control units 228L2 and 228R2 in the illumination control unit 228 correspond to a control unit in a narrow sense.

[0111] Furthermore, another aspect of the present invention is a lighting unit 10 as a vehicle lamp. The lighting unit 10 adjusts the optical axis position when the inclination angle of the vehicle 300 with respect to the horizontal plane changes while the vehicle is stopped, and maintains the optical axis position when the inclination angle of the vehicle 300 with respect to the horizontal plane changes while the vehicle is traveling.

[0112] Yet another aspect of the present invention is a method for controlling a vehicle lamp, which adjusts the position of the optical axis O of the lamp unit 10 based on the inclination angle of the vehicle 300 with respect to the horizontal plane detected by the inclination detection device, if the inclination angle of the vehicle 300 with respect to the road surface changes, and maintains the position of the optical axis if the inclination angle of the road surface with respect to the horizontal plane changes.

[0113] The present invention is not limited to the above-mentioned embodiments, and it is possible to combine the embodiments, or to add various modifications such as design changes based on the knowledge of a person skilled in the art, and such combined or modified embodiments are also included in the scope of the present invention. New embodiments resulting from combinations of the above-mentioned embodiments with each other, or combinations of the above-mentioned embodiments with the following modifications, have the same effects as the combined embodiments and modifications.

[0114] In each of the above-mentioned embodiments, the vehicle control unit 302 or the irradiation control unit 228 may determine the traveling state of the vehicle (including whether the vehicle is moving straight or not, and calculation of the motion acceleration of the vehicle 300), determine the optical axis position, and determine the light distribution pattern. When the irradiation control unit 228 performs these determinations, information from various sensors and the navigation system is transmitted to the irradiation control unit 228 via the vehicle control unit 302. When the irradiation control unit 228 performs these determinations, one or both of the irradiation control unit 228L and the irradiation control unit 228R can perform these determinations. In addition, the irradiation control unit 228 may control the leveling actuator 226 as the optical axis adjustment unit without the intervention of the leveling control unit 236. That is, the irradiation control unit 228 may function as the leveling control unit 236. When the vehicle control unit 302 performs these determinations, the irradiation control unit 228 controls the turning on and off of the bulb 14, the driving of the swivel actuator 222, the leveling actuator 226, and the motor 238, and the like, based on instructions from the vehicle control unit 302. In this case, the vehicle control unit 302 constitutes a control device that executes the auto-leveling control.

[0115] The functional configuration of the vehicle lighting system may be modified as follows. Fig. 10 is a functional block diagram for explaining the operational cooperation of the headlamp unit, the vehicle control unit, and the leveling ECU in the vehicle lighting system according to the modified example. As described above, the right headlamp unit 210R and the left headlamp unit 210L are basically configured the same, so in Fig. 10, the headlamp unit 210R and the headlamp unit 210L are collectively referred to as the headlamp unit 210.

[0116] The leveling ECU 100 (a control device for vehicle lighting) includes a receiving unit 102, a control unit 104, a transmitting unit 106, a memory 108, an acceleration sensor 110, and a temperature sensor 112. The leveling ECU 100 is installed, for example, near the dashboard of the vehicle 300. The installation position of the leveling ECU 100 is not particularly limited, and may be installed, for example, in the headlight unit 210. The installation position of the acceleration sensor 110 is also not particularly limited, and may be installed, for example, outside the leveling ECU 100. For example, the acceleration sensor 110 can be installed at any position in the vehicle body or in the headlight unit 210. An acceleration sensor mounted on an ECU of another system equipped in the vehicle 300, such as an airbag system, may be used. Furthermore, multiple acceleration sensors may be used, such as a combination of the acceleration sensor 110 for the auto-leveling system and an acceleration sensor of another system. The installation position of the leveling ECU 100 and the installation position of the acceleration sensor 110 can be combined arbitrarily.

[0117] Furthermore, in this modification, the acceleration sensor 110 is used as an example of a tilt detection device, but the tilt detection device is not limited to the acceleration sensor 110, and other sensors such as a gyro sensor or a geomagnetic sensor may be used.

[0118] A vehicle control unit 302 and a light switch 304 mounted on the vehicle 300 are connected to the leveling ECU 100. Signals output from the vehicle control unit 302 and the light switch 304 are received by the receiving unit 102. The receiving unit 102 also receives output values ​​from the acceleration sensor 110 and the temperature sensor 112. A steering sensor 310, a vehicle speed sensor 312, a navigation system 314, and the like are connected to the vehicle control unit 302, and the vehicle control unit 302 can acquire various information from these sensors and transmit it to the leveling ECU 100 and the like. For example, the vehicle control unit 302 transmits an output value of the vehicle speed sensor 312 to the leveling ECU 100. This allows the leveling ECU 100 to detect the running state of the vehicle 300.

[0119] The light switch 304 transmits signals instructing to turn on / off the headlamp unit 210, signals instructing the light distribution pattern to be formed by the headlamp unit 210, signals instructing to execute auto-leveling control, etc. to the power source 306, the vehicle control unit 302, the leveling ECU 100, etc., depending on the operation content of the driver. For example, the light switch 304 transmits a signal instructing to execute auto-leveling control to the leveling ECU 100. As a result, the leveling ECU 100 starts the auto-leveling control of each of the above-mentioned embodiments.

[0120] The signal received by the receiving unit 102 is transmitted to the control unit 104. The control unit 104 derives a change in the inclination angle of the vehicle 300 based on the output value of the acceleration sensor 110 transmitted from the receiving unit 102 and information stored in the memory 108 as necessary, and generates a control signal that instructs adjustment of the optical axis of the lamp unit 10. The control unit 104 outputs the generated control signal from the transmitting unit 106 to the leveling actuator 226.

[0121] The vehicle 300 is equipped with a power source 306 that supplies power to the leveling ECU 100, the vehicle control ECU 302, and the headlamp unit 210. When a light switch 304 is operated to instruct the headlamp unit 210 to be turned on, power is supplied from the power source 306 to the bulb 14 via the power supply circuit 230.

[0122] In addition, when comparing the configuration of this modified example (see FIG. 10) with the configuration of embodiment 1 (see FIG. 2), the leveling ECU 100 of this modified example corresponds to the irradiation control unit 228 (228R, 228L) of embodiment 1. In addition, the receiving unit 102 corresponds to the receiving units 228L1, 228R1, the control unit 104 corresponds to the control units 228L2, 228R2, the transmitting unit 106 corresponds to the transmitting units 228L3, 228R3, the memory 108 corresponds to the memories 228L4, 228R4, and the acceleration sensor 110 corresponds to the acceleration sensor 316, respectively. [Explanation of symbols]

[0123] O optical axis, 10 lighting unit, 200 vehicle lighting system, 226 leveling actuator, 228, 228L, 228R irradiation control unit, 228L1, 228R1 receiving unit, 228L2, 228R2 control unit, 228L3, 228R3 transmitting unit, 236 leveling control unit, 300 vehicle, 316 acceleration sensor.

Claims

1. A control device for a vehicle lamp having a function of controlling an illumination direction of a vehicle lamp in the vertical direction of a vehicle based on information from an inclination detection device, Calculating information about a road surface angle based on a detection value of the inclination detection device when the vehicle is stopped; adjusting the irradiation direction based on information regarding a vehicle attitude angle obtained from a detection value of the inclination detection device while the vehicle is stopped and information regarding the road surface angle; The tilt detection device and a temperature sensor are provided in the control device. A control device for vehicle lighting.

2. calculating information about the road surface angle from a difference between a detection value of the inclination detection device when the vehicle starts moving and a detection value of the inclination detection device when the vehicle stops; The vehicle lighting control device according to claim 1 .

3. When the vehicle is stopped, information regarding the road surface angle is calculated from a difference between the detection values ​​of the inclination detection device before and after the vehicle starts moving. The vehicle lighting control device according to claim 1 .

4. A control device for a vehicle lamp having a function of controlling an illumination direction of a vehicle lamp in a vertical direction of a vehicle based on information from an inclination detection device, adjusting the irradiation direction based on a difference between a detection value of the inclination detection device when the vehicle is stopped and a detection value of the inclination detection device while the vehicle is stopped, and a reference value related to a vehicle attitude angle; The tilt detection device and a temperature sensor are provided in the control device. A control device for vehicle lighting.

5. A control device for a vehicle lamp having a function of controlling an illumination direction of a vehicle lamp in a vertical direction of a vehicle based on information from an inclination detection device, adjusting the irradiation direction based on a difference between a detection value of the tilt detection device when the vehicle is stopped and a detection value of the tilt detection device while the vehicle is stopped; The tilt detection device and a temperature sensor are provided in the control device. A control device for vehicle lighting.

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