JP2002178829A - Automatic optical axis direction adjusting device of head lamp for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an uneasiness from being given to an operator when the optical axis direction of a head lamp is controllably turned in the right and left directions based on the steering angle of a steering wheel. SOLUTION: A filter for changing the responsiveness of the lights for swivel lamp (head lamps) 11R and 11L when the optical axis thereof is turned is switched based on the steer angle variation amount and the displacement direction of the steering wheel 15 detected by a steering angle sensor 16. The optical axis direction of the swivel lamps 11R and 11L is adjusted based on a swivel control angle obtained by using the filter. In this case, when the steering wheel is steered rapidly, a weak filter is selected and, when the steering wheel 15 is steered slowly, a strong filter is selected. By this filter treatment, the light directions of the swivel lamps 11R and 11L can be controllably turned without an uneasiness according to the steering of the steering wheel 15 by the operator.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle headlight for automatically adjusting the optical axis direction and irradiation range of left and right front irradiation by a headlight disposed on a vehicle in conjunction with a steering angle of a steering wheel. The present invention relates to a lamp optical axis direction automatic adjustment device.

[0002]

2. Description of the Related Art Conventionally, as a prior art document related to a headlight optical axis direction automatic adjusting device for a vehicle, Japanese Patent No. 29508 is known.
No. 97 is known. In this technology, a technique is disclosed in which the optical axis direction of a headlight (vehicle lamp) is changed in the left-right direction according to the steering angle (steering steering angle) of a steering wheel of a vehicle. And
A dead zone is provided near the neutral point of the steering angle to prevent the headlight from swinging in the left-right direction in the optical axis direction in conjunction with the play angle near the neutral point of the steering wheel steering angle and fine operation. The swivel control of the headlight that meets the driver's request is performed by changing the width of the headlight according to the vehicle speed.

[0003] Also, Japanese Patent Application Laid-Open No. 2-81743 discloses that
It describes that the irradiation angle of the headlight is changed according to the steering angle and the vehicle speed.

[0004]

By the way, according to these prior arts, even when the steering wheel is operated gently, the headlight is controlled with respect to the steering angle beyond the dead zone of the steering wheel. The axial direction swings in the left-right direction, giving a driver a sense of incongruity.

SUMMARY OF THE INVENTION The present invention has been made in order to solve such a problem, and it is intended to give a driver an uncomfortable feeling when the optical axis of a headlamp is swiveled to the left or right based on the steering angle of a steering wheel. It is an object of the present invention to provide a vehicle headlight optical axis direction automatic adjustment device without a headlight.

[0006]

According to the automatic headlight optical axis direction adjusting device for a vehicle according to the first aspect, the responsiveness changing means changes the vehicle speed by changing the steering angle of the steering wheel detected by the steering angle detecting means. Responsiveness when swiveling in the optical axis direction of the headlight is changed. The direction of the optical axis of the headlight is adjusted by the swivel control means based on the angle thus obtained. Thus, an effect is obtained in which the optical axis direction of the headlight is swivel-controlled without a sense of incongruity in accordance with the driver's steering of the steering wheel.

In the responsiveness changing means in the automatic headlight optical axis direction adjusting device for a vehicle according to the second aspect, the filter is switched to change the responsiveness. At this time, a weak filter is selected when the steering wheel is steered quickly, and a strong filter is selected when the steering wheel is steered slowly. According to the filter processing using the selected filter, an effect is obtained that the optical axis direction of the headlight is swivel-controlled without a sense of incongruity according to the steering of the driver's steering wheel.

According to a third aspect of the present invention, there is provided a vehicle headlight optical axis direction automatic adjusting apparatus, wherein the steering angle detecting means includes a play angle near a neutral point of a steering angle of a steering wheel and an optical axis direction of the headlight linked to a fine operation. Of the steering wheel in the left-right direction can be prevented, and the steering operation without a sense of incongruity can be performed.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples.

FIG. 1 is a schematic diagram showing the overall configuration of a vehicle headlight optical axis direction automatic adjusting apparatus according to an embodiment of the present invention.

In FIG. 1, right and left headlights 10L and 10R as headlights and left and right swivel lights 11L and 11R are provided on the front of the vehicle. Reference numeral 20 denotes an ECU (Electronic Control Unit). The ECU 20 includes a CPU 21 serving as a central processing unit for executing various known arithmetic processing, a ROM 22 storing a control program, and an RA storing various data.
It is configured as a logical operation circuit including an M23, a B / U (backup) RAM 24, an input / output circuit 25, and a bus line 26 connecting them.

The ECU 20 includes the steering wheel 1
Output signals from the steering angle sensor 16 that detects the steering angle STA of No. 5 and various sensor signals are input. And E
An output signal from the CU 20 is input to each of the actuators 12L and 12R of the left and right swivel lights 11L and 11R of the vehicle.
The optical axis directions of 1L and 11R are adjusted.

In the configuration of the present embodiment, as shown in FIG. 2, the headlight (left) light distribution area (low beam) by the headlight 10L and the headlight 10R
The headlight (right) light distribution area (low beam) is fixed, and the light distribution area by the swivel light 11L according to steering to the left from the neutral point of the steering wheel 15, and the light distribution area from the neutral point of the steering wheel 15 to the right. The light distribution area by the swivel light 11R is adjusted within the swivel control range in accordance with the steering in the direction.

FIG. 3 is a flowchart showing a processing procedure for selecting a filter in the CPU 21 in the ECU 20 used in the automatic headlight optical axis direction adjusting device for a vehicle according to one embodiment of the present invention. This will be described with reference to FIGS. 4, 5 and 6. Here, FIG. 4 is a map for obtaining the swivel target angle using the steering angle as a parameter in FIG. FIG. 5 is a time chart showing transition states of the steering angle of the steering wheel 15 to the right, the swivel target angle, and the swivel control angle corresponding to the processing of FIG. FIG. 6 is an explanatory diagram showing the movement of the light distribution area of the swivel light 11R corresponding to the swivel control angle in FIG. This filter selection routine is repeatedly executed by the CPU 21 at predetermined time intervals.

In FIG. 3, in step S101, a steering angle (steering angle) of the steering wheel 15 is set.
It is determined whether the STA exceeds 0 (zero), that is, whether the STA has a plus (positive) sign. When the steering angle STA is a plus sign, for example, it indicates that the steering wheel 15 is being steered to the right. When the determination condition of step S101 is satisfied, that is, when the steering angle STA is a plus sign and the steering wheel 15 is steered to the right, the process proceeds to step S102, and the unit time is 1 [s
ec: seconds], it is determined whether the steering angle change amount (steering change angle) DSTA exceeds 60 [° / sec].

If the determination condition of step S102 is satisfied, that is, if the steering angle change amount DSTA exceeds 60 [° / sec] and the steering wheel 15 is quickly steered to the right, the process proceeds to step S103, and the weak filter is set. This routine is selected and this routine ends. According to the filtering process using the weak filter selected at this time,
The swivel control angle SWC based on the swivel target angle SWT corresponding to the transition state of the steering angle STA of the steering wheel 15 responds sensitively to a small change in the steering angle STA.

In this case, first, as shown in FIG. 4, a swivel target angle SWT corresponding to the displacement of the steering angle STA exceeding the dead zone (-α <STA <α) is obtained. By applying a weak filter to the swivel target angle SWT, a swivel control angle SW having a linear quick response is provided.
C is obtained (see a steep rise “A” at the swivel control angle SWC in FIG. 5). Then, according to the swivel control angle SWC, the left and right swivel lights 11L, 1L
Automatic adjustment is performed in the optical axis direction of 1R (the arrow direction “A” indicating the movement of the light distribution area of the swivel light 11R in FIG. 6 corresponding to the steep rising “A” at the swivel control angle SWC in FIG. 5). reference).

On the other hand, the determination condition of step S102 is not satisfied, that is, the steering angle change amount DSTA is 60 [° / sec.
c] When it is smaller than the following, the process proceeds to step S104,
It is determined whether the steering angle change amount DSTA is less than -90 [° / sec]. When the steering angle change amount DSTA is a minus (negative) sign, it indicates that the steering angle STA of the steering wheel 15 is on the return side (left direction). When the determination condition in step S104 is satisfied, that is, when the steering angle change amount DSTA is smaller than -90 [° / sec] and the steering wheel 15 is quickly returned to the left, the process proceeds to step S103 described above. The weak filter is selected, and this routine ends.

On the other hand, the determination condition of step S104 is not satisfied, that is, the steering angle change amount DSTA is 60 [° / sec.
c] to -90 [° / sec], and when the steering wheel 15 is slowly steered to the right or returned slowly to the left, step S105.
Then, a strong filter is selected, and this routine ends. According to the filtering process using the strong filter selected at this time, the steering angle S of the steering wheel 15 is determined.
The swivel control angle SWC based on the swivel target angle SWT corresponding to the transition state of the TA is such that the high-frequency component of the vibration is removed from the steering angle STA and there is no small fluctuation.

In this case, first, as shown in FIG. 4, a swivel target angle SWT corresponding to the displacement of the steering angle STA exceeding the dead zone (−α <STA <α) is obtained. By applying a strong filter to the swivel target angle SWT, a swivel control angle SWC having a dull response can be obtained (“B” without a large change in the swivel control angle SWC in FIG. 5, a gentle fall ” C "). And
In accordance with the swivel control angle SWC, automatic adjustment of the left and right swivel lights 11L and 11R in the optical axis direction is performed ("B" without a large change in the swivel control angle SWC in FIG. 5; A steering position “B” indicating the movement of the light distribution area of the swivel light 11R in FIG. 6 corresponding to “C” in FIG. 6, and an arrow direction “C”).

If the condition of step S101 is not satisfied, that is, if the steering angle STA is 0 (zero) or a minus sign and the steering wheel 15 is steered to the neutral point or to the left, the process proceeds to step S106. ,
It is determined whether the steering angle change amount DSTA is less than -60 [° / sec]. The determination condition of step S106 is satisfied, that is, the steering angle change amount DSTA is −60 [° / sec.
c], the steering wheel 15 is steered quickly to the left in a small direction, the process proceeds to step S107, a weak filter similar to that in step S103 is selected, and this routine ends.

On the other hand, the determination condition of step S106 is not satisfied, that is, the steering angle change amount DSTA is -60 [° / sec.
c] When it is larger than the above, the process proceeds to step S108,
It is determined whether the steering angle change amount DSTA exceeds 90 [° / sec]. The determination condition of step S108 is satisfied, that is, the steering angle change amount DSTA is 90 [° / sec].
When the steering wheel 15 is quickly returned to the right direction largely beyond the above, the process proceeds to the above-described step S107, and similarly, a weak filter is selected, and this routine ends. On the other hand, the determination condition of step S108 is not satisfied, that is, the steering angle change amount DSTA is −60 [° / sec.
c] to 90 [° / sec], and when the steering wheel 15 is slowly steered leftward or slowly returned rightward, the above-described step S1 is performed.
The process proceeds to 05, a similarly strong filter is selected, and this routine ends.

As described above, the apparatus for automatically adjusting the optical axis direction of the vehicle headlamp according to the present embodiment includes the steering wheel 15 of the vehicle.
A steering angle sensor 16 as a steering angle detecting means for detecting the steering angle STA [°] of the steering angle STA, and a steering angle change amount DSTA [° / °] as a displacement speed of the steering angle STA detected by the steering angle sensor 16 per unit time. sec], the responsiveness when the optical axis directions of the left and right swivel lights (headlights) 11L and 11R of the vehicle are swiveled in the left and right direction parallel to the horizontal plane according to the displacement direction represented by the minus / plus signs. The optical axis of the swivel lights 11L and 11R based on the responsiveness changing means achieved by the ECU 20 and the swivel control angle SWC obtained by the responsiveness changing means with respect to the steering angle STA detected by the steering angle sensor 16. And a swivel control means achieved by the ECU 20 for adjusting the direction.

That is, the swivel light 11L, depending on the steering angle change amount DSTA of the steering angle STA of the steering wheel 15 detected by the steering angle sensor 16 and the displacement direction.
Responsiveness when swiveling in the optical axis direction of 11R is changed. The optical axis directions of the swivel lights 11L and 11R are adjusted based on the swivel control angle SWC obtained as described above. Thereby, the swivel control of the optical axis direction of the swivel lights 11L and 11R can be performed without a sense of incongruity according to the steering of the steering wheel 15 by the driver.

The responsiveness changing means achieved by the ECU 20 of the vehicle headlamp automatic optical axis direction adjusting device of this embodiment is a responsiveness changing means that switches the filters to control the swivel lights 11L and 11R based on the swivel control angle SWC. This is to change the response of the optical axis direction adjustment. At this time, a weak filter is selected when the steering wheel 15 is steered quickly, and a strong filter is selected when the steering wheel 15 is steered slowly. According to the filter processing using the selected filter, the swivel control of the optical axis directions of the swivel lights 11L and 11R can be performed without any uncomfortable feeling according to the steering of the steering wheel 15 by the driver.

A steering angle sensor 1 as a steering angle detecting means of the vehicle headlight optical axis direction automatic adjusting apparatus of the present embodiment.
Numeral 6 sets a dead zone near the neutral point “0 (zero) [°]” of the steering angle STA. Thereby, the swivel light 11L, which is linked to the play angle and the fine operation near the neutral point of the steering angle STA of the steering wheel 15,
11R can be prevented from swinging in the left-right direction in the optical axis direction, and steering operation without a sense of incongruity can be performed.

In the above embodiment, swivel lights 11L and 11R are provided as left and right headlights 10L and 10R as headlights of the vehicle to achieve swivel control. When practicing the invention,
It is not limited to this, and the headlights 10L,
The 10R may be swiveled directly by the actuator.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing the entire configuration of a vehicle headlight optical axis direction automatic adjustment device according to an example of an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a light distribution area of a headlight and a swivel light in the vehicle headlight optical axis direction automatic adjustment device according to one example of an embodiment of the present invention.

FIG. 3 is a flowchart showing a filter selection processing procedure in a CPU in an ECU used in a vehicular headlamp automatic optical axis direction adjusting apparatus according to one embodiment of the present invention.

FIG. 4 is a map for obtaining a swivel target angle using the steering angle in FIG. 3 as a parameter.

FIG. 5 is a time chart showing transition states of a steering angle, a swivel target angle, and a swivel control angle of the steering wheel to the right, corresponding to the processing of FIG. 3;

FIG. 6 is an explanatory diagram showing the movement of the light distribution area of the swivel light corresponding to the swivel control angle in FIG.

[Explanation of symbols]

 11L, 11R Swivel light (headlight) 12L, 12R Actuator 15 Steering wheel 16 Steering angle sensor (Steering angle detecting means) 20 ECU (Electronic control unit)

Continued on front page (72) Inventor Kunio Ohashi 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Yuji Yamada 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Yoshiyuki Miki 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F-term (reference) 3K039 AA08 CC01 GA02 JA03

Claims (3)

[Claims] 1. A steering angle detecting means for detecting a steering angle of a steering wheel of a vehicle, and an optical axis direction of a headlight of the vehicle is swiveled by a displacement speed of the steering angle detected by the steering angle detecting means. Swiv
el: responsiveness changing means for changing the responsiveness when the vehicle turns, and for the steering angle detected by the steering angle detecting means,
A swivel control unit that adjusts the optical axis direction of the headlight based on the angle obtained by the responsiveness changing unit. 2. The responsiveness changing means changes responsiveness by switching a filter.
4. The automatic headlight optical axis direction adjusting device according to claim 1. 3. The steering angle detecting means sets a dead zone near a neutral point of the steering angle.
4. The automatic headlight optical axis direction adjusting device according to claim 1.