JP2013049344A - Optical axis control method and device of vehicular headlamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical axis control means capable of reducing cost, by arranging a device part only in the vicinity of a headlamp.SOLUTION: An inner surface of an outer frame of the headlamp 10 is provided with an inclination sensor 14 for detecting a vehicle body inclination to a horizontal plane h, an optical axis adjuster 20, and an actuator 22 for operating the optical axial adjuster 20. This optical axis control device includes a door opening-closing sensor 24, and a wheel speed sensor 26. A controller 30 has a memory 32 for storing a vehicle body inclination α detected by the inclination sensor 14, a stopping-starting determining part 34 for determining whether or not a vehicle is in a stopping state or after starting from a detecting value of the door opening-closing sensor 24 and the wheel speed sensor 26, and a difference calculating part 36 for calculating a difference β1 or β2 between a vehicle body inclination α1 in the initial setting of the vehicle or a vehicle body inclination α3 when stopping the vehicle, and a vehicle body inclination α2 after starting the vehicle, and adjusts an optical axis angle θ of the headlamp 10 based on the difference β1 or β2.

Description

  The present invention relates to an optical axis control method and apparatus for a vehicle headlamp that can be simplified in structure and reduced in cost.

  Vehicle headlamps (headlamps) are initially adjusted so that the optical axis angle (the inclination angle of the optical axis with respect to the horizontal plane) satisfies the legal standards at the time of factory shipment or vehicle inspection. For example, the optical axis of the headlamp is adjusted in a state in which no occupants and loads are placed on a horizontal plane, that is, in a state where the vehicle is not inclined forward and backward with respect to a horizontal plane (road surface).

  By the way, the direction (irradiation direction) of the optical axis of the headlamp with respect to the road surface changes depending on the posture of the vehicle in the front-rear direction (the inclination of the vehicle with respect to the road surface). For example, if the rear side of the vehicle is tilted to sink, the headlamps are directed upward, so the direction of the optical axis tends to be upward.If the front side of the vehicle is tilted to sink, the headlamps are directed downward. The direction of the optical axis tends to be downward. Depending on the degree of inclination of the vehicle in the front-rear direction, the oncoming vehicle may be dazzled by the headlight of the own vehicle, or the direction of the optical axis may be too downward to illuminate the front accurately.

  Therefore, an auto leveling device is known that adjusts the optical axis angle of the headlamp according to the posture (tilt) of the vehicle body in the front-rear direction so that the direction of the optical axis of the headlamp with respect to the road surface is not greatly changed.

  Conventional optical axis control of headlamps is provided with vehicle height sensors at the front and rear parts of the vehicle body, and the distance from the ground is measured at the front and rear parts of the vehicle body. The inclination angle in the longitudinal direction of the vehicle is detected, and based on this inclination angle, the optical axis angle is adjusted so that the direction of the optical axis of the headlamp (irradiation direction) is appropriate. An optical axis control device of a method according to Patent Document 1 is disclosed. Patent Document 2 discloses an optical axis control apparatus using a GPS system.

JP 2009-78810 A JP 2005-206071 A

  The optical axis control device disclosed in Patent Document 1 requires vehicle height sensors to be arranged at the front and rear of the vehicle, and the system becomes large. There is a problem of cost. Similarly, the optical axis control device using the GPS system disclosed in Patent Document 2 cannot avoid cost increase.

  In view of the problems of the prior art, the present invention has a simple configuration in which a sensor for detecting the inclination angle of the vehicle body is arranged in or near the headlamp, and the cost can be reduced. It aims at realizing the optical axis control means of a headlamp.

  In order to achieve this object, an optical axis control method for a vehicle headlamp according to the present invention automatically adjusts the optical axis direction of the headlamp with respect to a vehicle body posture that changes when the vehicle is stopped. In the optical axis control method of the lamp, a reference value setting step for detecting and storing the inclination angle of the vehicle body with respect to the horizontal plane when the vehicle stops from the running state, and the inclination angle of the vehicle body with respect to the horizontal plane when the vehicle starts from the stop state The difference calculation step for calculating the difference between the vehicle body inclination angle detected in the reference value setting step and the vehicle body inclination angle detected in the change amount detection step, and the optical axis direction of the headlamp It includes an optical axis angle correction step of correcting the angle by the difference calculated in the calculation step.

  The change factor of the optical axis angle is the posture of the vehicle body in the longitudinal direction, and the change of the optical axis angle occurs while the vehicle is stopped. Also, the factors that change the vehicle's longitudinal posture are vehicle factors such as loading / unloading of passengers, increase / decrease of passengers or change of their weight distribution, tire wear, increase / decrease of fuel, decrease of tire pressure, vehicle maintenance, etc. A possible cause outside the vehicle is the slope of the road surface. In the present invention, factors outside the vehicle are not considered.

  That is, in FIG. 3, (A) shows that the angle of the optical axis L of the headlight 102 provided on the front side front surface of the vehicle 100 with respect to the road surface r satisfies the legal standard in a state where the road surface r is parallel to the horizontal plane. The case where it is within the range, that is, the case where the inclination of the vehicle 100 with respect to the road surface r is within the allowable range is shown. (B) shows the case where the angle of the optical axis L with respect to the road surface r deviates from the legal standard due to some vehicle factor, that is, the case where the inclination of the vehicle 100 with respect to the road surface r is outside the allowable range. In the case of (B), it is necessary to change the optical axis direction.

  FIG. 3C shows a state where the angle of the optical axis L with respect to the road surface r is within a range satisfying the legal standards, that is, the inclination of the vehicle 100 with respect to the road surface r in a state where the road surface r is inclined with respect to the horizontal surface h. Indicates the case where is within the allowable range. Also in this case, since the angle of the optical axis L with respect to the road surface r is maintained within a range that satisfies the legal standard, it does not hinder travel. Therefore, adjustment in the optical axis direction is unnecessary.

  Specifically, the method of the present invention compares the inclination angle of the vehicle body (headlight) immediately after stopping from the running state with the inclination angle of the vehicle body (headlight) immediately after starting running from the stopped state. The amount of change (change angle) is obtained, and the optical axis angle of the headlamp is adjusted by the change angle. Thus, for example, when the vehicle is stopped on a flat road surface (that is, when no occupant or luggage is mounted) (at this time, the inclination angle of the vehicle body is 0 degree), the luggage is then loaded and the vehicle body is loaded. When the vehicle is tilted 10 degrees upward with respect to the horizontal, the tilt angle is stored when the vehicle starts to travel, and the tilt angle stored before the travel (here, when the vehicle has stopped from the previous travel) is stored. Compared with (0 degree), the difference, that is, the angle of the 10-degree spectroscopic axis is adjusted downward, so that the direction of the optical axis is adjusted appropriately.

  After that, when the vehicle is stopped in a state where the inclination angle of the vehicle body (headlight) is inclined upward by 10 degrees (a load is loaded), the inclination angle of the vehicle body (headlight) at that time is Remembered. And when the load is unloaded while the vehicle is stopped and the tilt angle changes, the tilt angle of the vehicle body changes by the amount tilted by the load. Only the adjustment is made so that the angle of the optical axis is returned to the upper side. Basically, there is no need to consider the inclination of the road surface because the road surface angle does not change between when the vehicle is stopped and when the traveling is started again.

  In this way, the difference between the vehicle body tilt angle detected when the vehicle is stopped (before the vehicle starts) and the vehicle body tilt angle detected after the vehicle starts is calculated, and the optical axis angle is corrected by this difference after the vehicle starts. Therefore, the optical axis angle can be maintained at an appropriate value in response to a change in the vehicle body posture that occurs while the vehicle is stopped. As a result, a simple and low-cost means is required which simply provides a sensor for detecting the vehicle body inclination angle in the headlamp or in the vicinity of the headlamp.

  Moreover, it is not necessary to adjust the optical axis angle while the vehicle is running after that, only by adjusting the optical axis angle after starting the vehicle. Therefore, it is possible to prevent shaking of the headlamp light that occurs due to the optical axis angle adjustment performed while the vehicle is running. In addition, after the initial adjustment of the optical axis angle, which is performed when the vehicle is shipped from the factory or at the time of vehicle inspection, it is not necessary to set the optical axis angle one by one.

  In the method of the present invention, an initial reference value setting step for detecting and storing the inclination angle of the vehicle with respect to the horizontal plane when the optical axis angle of the headlamp is adjusted so as to conform to the legal standards, and after the initial reference value setting step An initial travel determination step for determining whether or not it is the first travel, and only when the initial travel determination step is determined to be the first travel after the initial reference value setting step, the initial reference value setting step in the difference calculation step The difference between the detected vehicle body inclination angle and the vehicle body inclination angle detected in the change amount detection step may be calculated.

  When the vehicle is shipped from the factory or at the time of vehicle inspection, the optical axis angle of the headlamp (the inclination angle of the optical axis with respect to the horizontal plane) is initially adjusted so as to satisfy the legal standards. Therefore, when it is determined in the initial driving determination step that the vehicle is the first driving after the initial reference value setting step, the vehicle body inclination angle detected in the initial reference value setting step is used as the vehicle body inclination angle immediately after the vehicle stops, The difference from the vehicle body inclination angle is calculated. As a result, the optical axis angle is accurately adjusted even during the first run after factory shipment or vehicle inspection.

  In the method of the present invention, the determination immediately after the vehicle stops and immediately after the start of the vehicle may be determined from the open / closed state of the door and the traveling speed of the vehicle. That is, the detection timing of the vehicle body inclination angle immediately after the vehicle stops and immediately after the start is determined from the door open / closed state and the traveling speed. Thus, for example, when starting, the vehicle body tilt angle is detected when it is determined that the door is closed and the vehicle body tilt angle does not change due to increase or decrease of luggage or passengers. Since it is possible to detect the vehicle body inclination angle after determining that the vehicle has stopped reliably from the state, it is possible to more accurately calculate the change in the vehicle body inclination angle caused by loading and unloading of the load and the passenger getting on and off.

  The optical axis control device for a vehicle headlamp according to the present invention, which can be directly used for carrying out the method of the present invention, is an optical axis control device for a vehicle headlamp provided with an actuator for changing the optical axis direction. An inclination angle detection device for detecting the inclination angle of the vehicle body with respect to the vehicle, a storage device for storing a detection value detected by the inclination angle detection device, vehicle state determination means for determining stop and start of the vehicle based on the vehicle speed, and start of the vehicle And calculating means for calculating a difference between the vehicle body inclination angle detected when the vehicle has stopped since the previous run and the vehicle body inclination angle when the vehicle started, And a controller that operates the actuator so as to correct the optical axis angle of the illumination lamp.

  In the device of the present invention, the difference between the vehicle body tilt angle detected when the vehicle is stopped (before the vehicle starts) and the vehicle body tilt angle detected after the vehicle starts is calculated, and the optical axis angle is corrected by this difference after the vehicle starts. Therefore, the optical axis angle can be maintained at an appropriate value in response to a change in the vehicle body posture that occurs while the vehicle is stopped. In addition, automatic control of the optical axis angle is possible, and a simple and low-cost configuration is required in which the vehicle body tilt angle sensor is disposed in the headlamp or in the vicinity of the headlamp.

  According to the method of the present invention, in the optical axis control method for a vehicle headlamp that automatically adjusts the optical axis direction of the headlamp with respect to the vehicle body posture that changes when the vehicle is stopped, the vehicle is stopped from the running state. A reference value setting process that detects and stores the inclination angle of the vehicle body relative to the horizontal plane, a change amount detection process that detects the inclination angle of the vehicle body relative to the horizontal plane when the vehicle starts from a stopped state, and a reference value setting process A difference calculating step for calculating a difference between the vehicle body inclination angle and the vehicle body inclination angle detected in the change amount detecting step, and an optical axis for correcting the angle of the optical axis direction of the headlamp by the difference calculated in the difference calculating step Since the angle correction step is included, it is not necessary to provide vehicle height sensors at the front and rear portions of the vehicle body, the apparatus configuration can be simplified and the cost can be reduced, and automatic control of the optical axis angle is facilitated.

  According to the device of the present invention, in the optical axis control device for a vehicle headlamp provided with an actuator for changing the optical axis direction, the tilt angle detecting device for detecting the tilt angle of the vehicle body with respect to the horizontal plane, and the tilt angle A storage device that stores detection values detected by the detection device, vehicle state determination means that determines stop and start of the vehicle based on the vehicle speed, and detection when the vehicle stops from the previous run when the start of the vehicle is determined Calculating means for calculating a difference between the vehicle body inclination angle and the vehicle body inclination angle when the vehicle starts, and a controller for operating the actuator so as to correct the optical axis angle of the headlamp by the difference after the vehicle starts Thus, the same effects as those of the method of the present invention can be obtained.

It is a block diagram which shows the optical-axis control means of the vehicle headlamp which concerns on one Embodiment of this invention method and this invention apparatus. It is a flowchart which shows the operation procedure of the said embodiment. It is explanatory drawing which shows the case where the optical axis angle control of the vehicle headlamp is required, and the case where it is not required.

  Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in this embodiment are not intended to limit the scope of the present invention to that unless otherwise specified.

  An embodiment of the method and the device of the present invention will be described with reference to FIGS. In FIG. 1, a headlamp 10 is provided on the front side front surface of a vehicle body (not shown). A reflector 12 is provided inside the headlamp 10. One end 12a of the reflector 12 is fixed, and the other end 12b is configured to be movable in the direction of the arrow. A valve 16 is provided in the center of the front surface of the reflector 12. The light from the bulb 16 is reflected by the reflector 12 and radiated to the front of the vehicle body via the lens 18. An optical axis adjuster 20 is provided on the back surface of the one end 12 b of the reflector 12, and an actuator 22 that operates the optical axis adjuster 20 and adjusts the optical axis L is provided adjacent to the optical axis adjuster 20. .

  An inclination angle sensor 14 for detecting the inclination angle of the vehicle body (headlamp 10) with respect to the horizontal plane h is mounted on the inner surface of the outer frame of the headlamp 10. A door opening / closing sensor 24 that detects the open / close state of the door and a wheel speed sensor 26 that detects the speed of the vehicle are provided in the vehicle, for example, in the driver's seat. The tilt angle sensor 14 is provided in each of the left and right headlamps 10 and is configured to measure the tilt angle of each of the left and right headlamps 10.

  Further, a controller 30 that controls the angle of the optical axis L is provided. The memory 32 of the controller 30 stores the inclination angle of the vehicle body (headlight 10) with respect to the horizontal plane h detected by the inclination angle sensor 14, and the opening / closing state of the vehicle body door detected by the door opening / closing sensor 24, and the wheel speed sensor. The vehicle speed detected at 26 is stored. The stop / start determination unit 34 is in a state (vehicle speed V = 0, door open) in which the vehicle can be loaded and unloaded and passengers can get on and off from the detection values of the door opening / closing sensor 24 and the wheel speed sensor 26. It is determined whether or not the vehicle is in a state where it is impossible to load / unload luggage or to / from passengers (vehicle speed V> 0, door closed).

  The difference calculation unit 36 calculates the difference in the inclination angle of the vehicle body (the headlamp 10) with respect to the horizontal plane h when the vehicle stops from the running state (the door opens immediately after the stop) and when the vehicle starts (the door closes immediately after the start). calculate. The controller 30 calculates the adjustment amount of the optical axis angle θ according to the difference, operates the actuator 22 based on the calculated optical axis angle adjustment amount, and adjusts the optical axis angle θ of the headlamp 10.

  The change (tilt) in the longitudinal posture of the vehicle body due to the vehicle factors described above occurs due to loading / unloading of luggage or getting on / off of passengers when the vehicle is stopped. Therefore, in the present embodiment, for example, the inclination angle of the vehicle body (headlight) before the occupant gets on or off the vehicle (immediately after the vehicle stops from the traveling state), the loading or unloading of the occupant, An inclination angle of the vehicle body (headlight) after the vehicle has started (when starting from a stopped state) is detected, and the difference is calculated. Then, by correcting the optical axis angle θ of the headlamp 10 by the calculated difference, it responds to the change (tilt) in the longitudinal posture of the vehicle body (the direction of the headlamp) caused by loading and unloading of luggage and getting on and off of passengers The optical axis angle can be controlled. Thereby, even if the vehicle body is inclined, the direction of the optical axis of the headlamp 10 with respect to the road surface is maintained in an appropriate direction.

  Hereinafter, the operation procedure of the present embodiment will be described with reference to FIG. When the vehicle is manufactured and shipped at the factory, or at the time of vehicle inspection, user inspection, parts replacement, etc., the optical axis angle θ is initially adjusted within legal compliance (S10). The initial adjustment of the optical axis angle θ is performed on a substantially horizontal plane while the vehicle is in an empty state (no load or passengers are loaded). Next, the inclination angle sensor 14 detects the inclination angle α1 of the vehicle body (headlight 10) with respect to the horizontal plane h in the initial adjustment state (at the time of factory shipment, immediately after vehicle inspection), and stores the inclination angle α1 at this time as an initial value. 32 (S12). If the road surface is horizontal, the inclination angle α = 0.

  At this time, an initial flag F is set (F = 1) (S13). The signal of the initial flag F is input to the memory 32. The initial flag F is set only at the time of factory shipment or after vehicle inspection, and is reset when the vehicle travels. While the vehicle is stopped, the posture (tilt) of the vehicle body changes due to loading / unloading of the load, increase / decrease of passengers, or changes in the distribution of their weight, etc., and this change changes the direction of the optical axis relative to the road surface. To do.

  Next, when the door is closed (S15) and the vehicle speed V> 0 (S16), the stop / start determination means 34 determines that the vehicle has started (S18). Next, the inclination angle α2 of the vehicle body (headlight 10) with respect to the horizontal plane h is detected by the inclination angle sensor 14, and stored in the memory 32 (S20). Next, since it is determined by the controller 30 that the initial flag F is set (F = 1), that is, it is determined that it is the first run after the initial adjustment (S21), the difference calculating unit 36 The initial inclination angle α1 stored at the time of the initial adjustment is compared with the inclination angle α2 immediately after traveling, and the difference β1 (β1 = α2-α1) is calculated (S22).

  Next, based on the calculated difference β1, an optical axis angle adjustment amount is calculated (S24), and the optical axis angle θ of the headlamp 10 is adjusted (S26). Then, the initial flag F is reset (F = 0) (S27). Next, when the vehicle speed V = 0 (S28) and the door is open (S29), the stop / start determination unit 34 determines that the vehicle has stopped (S30). Next, the inclination angle α3 of the vehicle body (headlight 10) with respect to the horizontal plane h immediately after the stop is detected by the inclination angle sensor 14, and stored in the memory 32 (S32).

  Thereafter (after the second control round), the procedure from S16 to S20 is performed in the same manner, and then the initial flag F is reset. Therefore, the difference calculation unit 36 stores the horizontal plane immediately after the previous stop of the vehicle. The inclination angle α3 of the vehicle body (headlight 10) with respect to h is compared with the inclination angle α2 detected when starting (immediately after), and the difference β2 (β2 = α3-α2) is calculated (S34). Next, an optical axis angle adjustment amount is calculated based on the calculated difference β2 (S36), and the optical axis angle θ of the headlamp 10 is adjusted by the actuator 22 (S38). Thereafter, the procedure from S28 to S38 is repeated, and the optical axis angle is adjusted each time.

  In addition, the inclination angle sensor 14 is provided in each of the headlamps 10 provided in a pair of left and right, and the above-described control is also performed on each of the left and right headlamps 10. Therefore, the automatic adjustment of the optical axis of the headlamp 10 is controlled independently on the left and right.

  According to the present embodiment, at the time of factory shipment or immediately after vehicle inspection, the vehicle body (headlight 10) with respect to the inclination angle α1 stored at the time of initial adjustment or the horizontal plane h detected when the vehicle stops from the running state (immediately after the vehicle stops). ) And a difference β1 or β2 between the inclination angle α2 of the vehicle body (headlight 10) with respect to the horizontal plane h detected at the time of vehicle start (immediately after vehicle start), and based on the differences β1 and β2. Since the optical axis angle θ of the headlamp 10 is corrected, the direction of the optical axis is appropriately adjusted in response to the change in the front-rear direction posture of the vehicle body (headlamp 10) that occurs while the vehicle is stopped. Can hold in the direction.

  For this reason, it is not necessary to arrange vehicle height sensors at the front and rear portions of the vehicle body to detect the vehicle body's longitudinal posture, and the optical axis can be adjusted with respect to the vehicle body's longitudinal posture change with a simple configuration. The cost of the device configuration can be reduced. In addition, since the optical axis can be adjusted independently by the left and right headlamps 10, for example, when the vehicle body is tilted left and right due to the loading of luggage, the degree of adjustment ( Although the angle changes, the optical axis is adjusted by the left and right headlamps 10, so that finer adjustment is possible.

  Moreover, it is not necessary to adjust the optical axis angle while the vehicle is running after that, only by adjusting the optical axis angle after starting the vehicle. Therefore, it is possible to prevent the fluctuation of the incident light of the headlamp 10 caused by the optical axis angle adjustment performed while the vehicle is traveling. In addition, it detects both the open / closed state of the door and the vehicle speed, and the vehicle is in a state where it can be loaded and unloaded and passengers can get on and off (vehicle speed V = 0, door open), or the vehicle is started Since it is determined whether the vehicle body tilt angle is detected by determining whether it is in a state where vehicle loading / unloading and occupant entry / exit are not possible (vehicle speed V> 0, door closed), A more accurate determination can be made with respect to a change in angle. Furthermore, the adjustment of the optical axis angle θ can be accurately performed even during traveling immediately after vehicle inspection, user inspection, parts replacement, and the like.

  In the above embodiment, it is determined whether the vehicle is stopped or the vehicle is started by detecting both the open / closed state of the door and the vehicle speed. However, only the vehicle speed is detected, and only the detected value of the vehicle is detected. You may make it determine stop or start.

  According to the present invention, it is possible to automate the optical axis control of a vehicle headlamp with simple and low-cost means, thereby eliminating a vehicle height sensor or the like conventionally attached to a suspension or the like.

DESCRIPTION OF SYMBOLS 10,102 Headlamp 12 Reflector 14 Inclination angle sensor 16 Valve 18 Lens 20 Optical axis adjuster 22 Actuator 24 Door open / close sensor 26 Wheel speed sensor 30 Controller 32 Memory 34 Stop / start determination part 36 Difference calculation part 100 Vehicle L Optical axis h Horizontal plane r Road surface θ Optical axis angle

Claims (4)

In the optical axis control method for a vehicle headlamp that automatically adjusts the optical axis direction of the headlamp with respect to the vehicle body posture that changes when the vehicle is stopped,
A reference value setting step for detecting and storing the inclination angle of the vehicle body relative to the horizontal plane when the vehicle is stopped from the running state;
A change amount detecting step for detecting an inclination angle of the vehicle body relative to a horizontal plane when the vehicle starts from a stopped state;
A difference calculating step for calculating a difference between the vehicle body inclination angle detected in the reference value setting step and the vehicle body inclination angle detected in the change amount detection step;
An optical axis control method for a vehicle headlamp, comprising: an optical axis angle correcting step of correcting an angle of the optical axis direction of the headlamp by the difference calculated in the difference calculating step. An initial reference value setting step for detecting and storing the inclination angle of the vehicle with respect to a horizontal plane when the optical axis angle of the headlamp is adjusted so as to meet the legal standards, and the first run after the initial reference value setting step Including an initial travel determination step for determining whether or not
The difference between the vehicle body inclination angle detected in the initial reference value setting step in the difference calculation step and the vehicle body inclination angle detected in the change amount detection step only when it is determined as the first travel in the initial travel determination step. The optical axis control method for a vehicle headlamp according to claim 1, wherein:   The method of controlling an optical axis of a vehicle headlamp according to claim 1 or 2, wherein the determination immediately after the vehicle stops and immediately after the start is determined from an open / closed state of the door and a traveling speed of the vehicle. In an optical axis control device for a vehicle headlamp equipped with an actuator that makes the optical axis direction variable,
An inclination angle detection device for detecting the inclination angle of the vehicle body relative to a horizontal plane;
A storage device for storing a detection value detected by the tilt angle detection device;
Vehicle state determination means for determining stop and start of the vehicle from the vehicle speed;
A calculating means for calculating a difference between a vehicle body inclination angle detected when the vehicle has stopped since the previous travel and a vehicle body inclination angle when the vehicle started when determining the start of the vehicle;
And a controller for operating the actuator so as to correct the optical axis angle of the headlamp by the difference after the start of the vehicle.

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