JPH11342787A - Automatic optical axis angle adjusting device for headlight of automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dissolve the inconvenience by the snapping of the wire of a car speed detection part. SOLUTION: When the wire of a car speed detection part 8 snaps, a microcomputer 3 judges the wire-snapped state of a car speed detection part 8 and the light axis angle set control signal (h) of an initial aiming position θ deg. is outputted to actuators 6, 7 and a warning signal (i) is outputted to a warning lamp. Thereby, as the optical axes of headlights RH, LH are returned and held to an intial aiming position θ deg., it is not feared that a dozzle is given to an oncoming car and the visual recognition of own car is dropped and the wire-snapped state of the car speed detection part 8 is warned to a driver.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a headlight which is suitable for the state of stopping and running of an automobile and which corresponds to a calculated front and rear inclination value of the vehicle body (hereinafter simply referred to as vehicle body inclination value). The present invention relates to a device for automatically adjusting an optical axis angle above and below a lamp (hereinafter simply referred to as an optical axis angle).
When the vehicle speed detection unit that detects the state of stopping and running of the automobile and outputs it as a vehicle speed signal is broken, the optical axis angle can be returned to the initial aiming position and held, and the warning unit can be operated, so-called vehicle speed. The present invention relates to a device for automatically adjusting the optical axis angle of an automotive headlamp having a disconnection warning function of a detection unit.

[0002]

2. Description of the Related Art The front and rear inclination of a vehicle with respect to a road surface (for example, the inclination of a vehicle body rising and falling) is determined by the number of persons riding the vehicle, the amount of load to be loaded, or the distribution of those loads, and the stopping and running of the vehicle. It changes according to the state and the like, whereby the vertical direction of the optical axis of the headlight also changes.
This is because, without knowing, the headlight's optical axis is too upward and dazzling the oncoming vehicle with the own vehicle's headlight, or the headlight's optical axis is too downward and the visibility is reduced Means that you may Therefore, being able to automatically adjust the optical axis of the headlight in accordance with the state of stopping or running of the vehicle and corresponding to the inclination of the vehicle body in front and rear is extremely useful for ensuring the safety of the own vehicle and the oncoming vehicle.

[0003] Various automatic headlamp optical axis angle adjusting devices for detecting the stopping and running state of an automobile, calculating the body inclination value, and automatically adjusting the optical axis angle have been filed. I have. Examples of this optical axis angle automatic adjusting device include, for example, Japanese Patent Application No. 8-344002 and Japanese Patent Application No. 8-34400.
No. 3, Japanese Patent Application No. 8-344004, Japanese Patent Application No. 8-3440
No. 05, Japanese Patent Application No. 8-344006, Japanese Patent Application No. 8-344
007 and so on. Hereinafter, two examples of the automatic optical axis angle adjusting device for a vehicle headlamp will be described with reference to FIGS.

FIGS. 6 to 12 show examples in which the vehicle body front displacement detecting section and the vehicle rear rear displacement detecting section are constituted by ultrasonic sensors or the like. FIG. 6 is a block diagram illustrating a device for automatically adjusting the optical axis angle of a vehicle headlamp according to a first example, FIG. 7 is a schematic view of a vehicle equipped with the automatic optical axis angle adjusting device illustrated in FIG. 6, and FIG. 9 is a signal waveform diagram showing the operation of each unit of each displacement amount detection unit, and FIGS. 10A and 10B are detection signals from each displacement amount detection unit in the microcomputer. 11 (a) and 11 (b) are waveform diagrams showing the average value of detection signals from the respective displacement amount detection units in the microcomputer, and FIG. FIG. 5 is an explanatory diagram showing a correlation between a vehicle body inclination average value, a set value voltage, and an optical axis control angle.

In FIGS. 1 and 2, reference numerals 1 and 2 denote a vehicle body front displacement detecting section and a vehicle rear rear displacement detecting section. The displacement detection units 1 and 2 are provided with ultrasonic sensors 1- and 2-
, Transmission units (transmission circuits) 1- and 2-, and reception units (reception circuits) 1- and 2-. Each of the ultrasonic sensors 1 and 2 is composed of a pair of transmitting and receiving ultrasonic vibrators and the like, and is provided on the bottom surface of the front part and the rear part of the vehicle body C of the automobile so as to face the road surface G, respectively. ing. Each of the transmission units 1-, 2-
Is used to connect the ultrasonic sensors 1- and 2-
At a constant frequency of 0 msec, at a high frequency of 40 KHz,
It vibrates for a fixed time of 0.1 msec.
That is, the ultrasonic waves are emitted from the ultrasonic sensors 1- and 2- toward the road surface G. Each of the receiving units 1-and 2 is connected to each of the ultrasonic sensors 1-and 2-
, And each of the transmitting units 1-2
Amplifying and waveform-shaping the reflected wave drawn out from the connection between-and each of the ultrasonic sensors 1- and 2-, and outputting the amplified and shaped waveforms as detection signals a and b.

In FIGS. 6 and 7, reference numeral 8 denotes a vehicle speed detecting section. The vehicle speed detection unit 8 outputs a pulse signal that changes according to the vehicle speed to the microcomputer 3 as a vehicle speed signal g when the vehicle is in a running state, and outputs a “LO” level signal when the vehicle is in a stopped state. It is output to the microcomputer 3 as a vehicle speed signal g.

In FIGS. 6 and 7, reference numeral 3 denotes a microcomputer as control means. The microcomputer 3 includes a counter, a D / A converter, an A / D converter, a memory, and the like, and receives detection signals a and b from the displacement amount detection units 1 and 2 at regular intervals, respectively. (Sampling), the respective detection signals a and b are averaged when a plurality of, in this example, the same number of ten, accumulate, and the vehicle body inclination value is calculated from the average value of the displacement amount between the front rear portion of the vehicle body and the road surface G. ,
In this example, the vehicle body inclination angle θ ° is calculated, and the vehicle body inclination angle θ is calculated.
This is for setting the optical axis angles of the headlights RH and LH described later corresponding to ° and outputting a setting signal c (for example, an analog voltage).

In FIGS. 6 and 7, reference numerals 4 and 5 denote a right motor control unit and a left motor control unit. The left and right motor control units 4 and 5 receive setting signals c from the microcomputer 3, respectively, and output position signals s1 and s1 output from position sensors of left and right actuators 6 and 7, which will be described later.
s2 (for example, an analog voltage) is compared with the setting signal c, and a control signal c 'for controlling the drive stop of the DC motors of the left and right actuators 6, 7 described later is output. The control signal c 'and the setting signal c constitute an optical axis angle setting control signal.

The left and right motor controllers 4 and 5 and the microcomputer 3 constitute control means. Note that the left and right motor controllers 4 and 5 provide the position signal s
1 and s2 are compared with the setting signal c to output a control signal c 'for controlling the DC motor. The microcomputer 3 performs the comparison control performed by the left and right motor controllers 4 and 5. It is also possible. In this case, the left and right motor controllers 4 and 5 can be omitted, and the microcomputer 3 outputs the control signal c 'directly to the left and right actuators 6 and 7. The control signal c 'in this case is an optical axis angle setting control signal.

In FIGS. 6 and 7, reference numerals 6 and 7 denote a right actuator (L / A) and a left actuator (L / A). These left and right actuators 6, 7
A DC motor (not shown) that receives control signals c ′ from the left and right motor control units 4 and 5 and controls the optical axes of headlights RH and LH described later, and a head motor RH and LH described later A position sensor that detects an optical axis position and outputs an analog voltage, and outputs the analog voltage output as position signals s1 and s2. The above-mentioned position sensor is, for example, a potentiometer, and the headlights RH and LH of the left and right actuators 6 and 7 which will be described later.
The position signals (analog voltages) s1 and s2 are output in conjunction with a rod for moving the optical axis up and down.

In FIGS. 6 and 7, RH and LH are a right headlight and a left headlight. This headlight RH,
LH is a headlamp of a reflector movable type, for example, in which a lamp chamber is defined by a lamp housing and a lens, and a light source bulb and a reflector are provided in this lamp chamber at least on a horizontal axis (horizontal axis perpendicular to the optical axis). It is provided so as to be rotatable up and down around an axis. Under the control of the left and right actuators 6 and 7, the reflector and the light source bulb rotate up and down, and the optical axis angles of the headlights RH and LH are controlled. The above-mentioned headlights RH and LH include, in addition to the above-mentioned reflector movable type, a lamp unit movable type in which the entire headlight rotates with respect to the vehicle body C. In addition to the above-described headlights that rotate vertically about the horizontal axis, there are also headlights that rotate left and right about the vertical axis.

Next, the operation of the above-described automatic optical axis angle adjusting device will be described with reference to FIGS. When the power is turned on to the automatic optical axis angle adjusting device, the vehicle speed detecting section 8 detects the stop and running state of the vehicle and outputs the detected state to the microcomputer 3 as a vehicle speed signal g. On the other hand, each of the transmission units 1 and 2 of the displacement amount detection units 1 and 2 transmits each of the ultrasonic sensors 1 and 2 at a constant period of 10 msec to 40K.
Vibration is performed at a high frequency of 0.1 Hz for a fixed time of 0.1 msec. FIG. 9A shows the output waveforms of the transmission units 1- and 2- at this time. By the operation of the transmission units 1-2, the ultrasonic sensors 1-2 emit ultrasonic waves toward the road surface G.

Here, the above-mentioned ultrasonic emission cycle T1 must satisfy the condition of the following equation (1). T1> 2Lo / v = 2Lo / 331.5 + 0.607t (sec) (1) where Lo: each ultrasonic sensor 1-2 when no vehicle is loaded
The distance between-and the road surface G: v: sound speed (m / sec) t: ambient temperature (° C) Each ultrasonic sensor 1-, when the above-mentioned vehicle body is not loaded,
The distance Lo between 2- and the road surface G is at most 0.5 m, and when the ambient temperature is, for example, 20 ° C., the above-described ultrasonic emission cycle T1 = 10 msec is sufficiently established.

Each of the ultrasonic sensors 1- and 2-oscillated by the operation of the above-described transmission units 1- and 2-
The ultrasonic wave having the waveform shown in FIG.
Fired one by one and 2Lo / 331.5 + 0.6
After 07 tsec, a reflected wave having the waveform shown in FIG. 9C is received.

When each of the ultrasonic sensors 1-2 receives a reflected wave, each of the receiving units 1-2 amplifies and shapes the above-mentioned reflected wave, and the amplified and shaped waveform, that is, FIG. The waveform shown in D) is sent to the microcomputer 3 as detection signals a and b at regular intervals (each ultrasonic sensor 1-).
, 2-). The detection signals a and b shown in FIG.
, 2-, a distance-time signal whose time width changes in accordance with the distance from the road surface G to each of the transmitters 1 in FIG.
Operation start time t1 of-and 2-, that is, FIG. 9B
9C from the ultrasonic emission start time t2 of each of the ultrasonic sensors 1 to 2 to the reflected wave reception start time t3 of each of the ultrasonic sensors 1 and 2 in FIG. Time, which changes in accordance with the distance from each of the ultrasonic sensors 1- and 2- to the road surface G) is “H”.
This is an "I" level signal.

Following the operation of each of the displacement detecting units 1 and 2 described above, the operation of the microcomputer 3 described above is shown in FIG.
The operation will be described with reference to the flowchart of FIG.

First, the microcomputer 3 includes, in each of the receiving units 1- 2 of the displacement detecting units 1 and 2 described above,
, 2- are input at a constant period (see FIGS. 10A and 10B). A plurality of the detection signals a and b are measured by a counter of the microcomputer 3. That is, “H” of each of the plurality of detection signals a and b
The "I" level time is added. Fig. 8-"Measurement of reception wave at front of vehicle body Measurement of reception wave at rear of vehicle body".

Next, go to the microcomputer 3
In, the measurement number (number of times) of each of the detection signals a and b described above is set in advance (N = 10 in this example),
The number of each of the detection signals a and b is counted and compared. When the measured number is less than 10, the detection signals a and b are measured again. That is, the “HI” level time of each of the plurality of detection signals a and b is continuously added until ten detection signals a and b are measured. Fig. 8-"Is N data stored?"

The measured number of the detection signals a and b is 10
(At time t1 in FIGS. 10 (a) and 10 (b)), and proceeds to the following formulas (2) and (3) to calculate the average value of the displacement between the front portion of the vehicle body and the road surface G. τF and the average value τR of the amount of displacement between the rear portion of the vehicle body and the road surface G are calculated. That is, the “HI” level time of each of the detection signals “a” and “b” added by 10 is divided by 10. τF = (τf1 + τf2 +... + τf9 + τf10) / 10 (2) τR = (τr1 + τr2 +... + τr9 + τr10) / 10 (3)
Is "HI" of the detection signals a and b obtained by adding the above ten signals.
11A and 11B show average values of the level time.
Shows the average time of the above-mentioned reflected wave or received wave. Fig. 8-"Average of N measured values of front body reception waves" Fig. 8-"Mean of N measured values of rear body reception waves".

Then, the vehicle body inclination angle θ is calculated based on the average value τF of the displacement amount (distance) between the front portion of the vehicle body and the road surface G and the average value τR of the displacement amount (distance) between the rear portion of the vehicle body and the road surface G.
Calculate °. That is, the distance between the ultrasonic sensor 1 of the vehicle body front displacement detecting unit 1 and the ultrasonic sensor 2 of the vehicle rear displacement detecting unit 2 is Xm, the average value τF of the displacement at the vehicle front and the vehicle body. Average value of displacement at the rear τR
Τsec, and the calculated body tilt angle is θ °.
Here, a difference τsec between the average value τF of the displacement amount at the front portion of the vehicle body and the average value τR of the displacement amount at the rear portion of the vehicle body is an (average) displacement amount between the front portion and the rear portion of the vehicle body C, and is expressed in time. When converted to the distance Ym, Y = τ (sec) × v (m / sec) = τ × (331.5 + 0.607t) [m] (4)

The above-mentioned vehicle body inclination angle θ ° is tan θ = Y / X (5) As a result, θ = tan ⁻¹ (Y / X) [°] (6) Fig. 8-"Calculation of body inclination".

Then, the process proceeds to step S3, where the optical axis angle set value voltage d0 corresponding to the vehicle body inclination angle θ ° calculated as described above is obtained.
To d6 are output to the left and right motor controllers 4 and 5 as setting signals c. FIG. 8— “Output optical axis angle set value voltage”.

Here, in FIG. 12, the vehicle body tilt average value (the average value of the vehicle body tilt angle θ ° calculated by the microcomputer 3 as described above) and the set value voltages d0 to d6 are shown.
A correlation between an optical axis control angle (an angle for controlling the optical axes of the headlights RH and LH up and down) (for example, an analog voltage output as a setting signal c to the left and right motor control units 4 and 5) is shown. . As is apparent from FIG. 12, when the vehicle body C is directed upward (upward), the optical axes of the headlights RH and LH are controlled downward, and when the vehicle body C is directed downward (downward), the headlights RH and LH are controlled. Is controlled upward, and the vehicle body C
The optical axes of the headlights RH and LH are controlled up and down by a control angle having a size corresponding to the size of the upward angle and the downward angle. In addition,
In FIG. 12 described above, the case where the vehicle body C is substantially parallel to the road surface G is “0”, the case where the average body inclination is upward is “+”, and the case where the average body inclination is downward. Is set to “−”, the case where the optical axis control angle is the downward control of the optical axis is “−”, and the case where the optical axis control angle is the upward control of the optical axis is “+”.

In FIG. 12, the optical axis control angle is controlled in blocks of 0.4 °. As a result, the optical axis control angle (for example, 0 °) is ± 0.2 with respect to the vehicle body inclination average value (for example, −0.2 ° to 0 ° to +0.2).
° width. However, the width of ± 0.2 ° does not dazzle the oncoming vehicle or reduce the visibility. In addition, if the width of the block of the above-mentioned optical axis control angle is made small, the optical axis control angles of the headlights RH and LH can be finely controlled. The step width of the optical axis control angle is determined in combination with the operation frequency of the left and right actuators 6 and 7.

Following the operation of the microcomputer 3, the operation of the left and right motor controllers 4, 5 and the left and right actuators 6, 7 will be described. The left and right motor control units 4 and 5 compare the setting signal c from the microcomputer 3 with the position signals s1 and s2 from the position sensors of the left and right actuators 6 and 7 until the two signals become equal. The control signal c 'is transmitted to the left and right actuators 6, 7
And when the two signals become equal, the output of the control signal c 'to the DC motor is stopped. The DC motors of the left and right actuators 6 and 7 are connected to the left and right motor control units 4 and 5 described above.
9 (a) and 9 (b), the driving is started from the time point t2 in FIGS. 9 (a) and 9 (b), and is stopped when the output of the control signal c 'is stopped.

As described above, the above-described device for automatically adjusting the optical axis of a headlight for a vehicle is suitable for the state of stopping and running of the vehicle, and corresponds to the calculated inclination angle θ ° of the front and rear of the vehicle body C. The vertical optical axis angles of the headlights RH and LH can be automatically adjusted. In addition, the number of the detection signals a and b to be input is not limited to the same number of 10 as described above.
The number may be one, or the number of input detection signals on the front side of the vehicle body and the number of input detection signals on the rear side of the vehicle body may be slightly different. The period T1 for inputting the detection signals a and b may be input at different periods other than the fixed period of 10 msec. Furthermore, the vehicle body inclination angle θ ° is calculated as the vehicle body inclination value,
The distances X and Y may be used instead of the angles.

FIGS. 13 to 17 show examples in which the vehicle body front displacement detecting section and the vehicle rear rear displacement detecting section are constituted by suspension sensors or the like. FIG. 13 is a block diagram showing a second example of a device for automatically adjusting the optical axis angle of a vehicle headlamp,
FIG. 14 is a schematic view of a vehicle equipped with the automatic optical axis angle adjusting device shown in FIG. 13, FIG. 15 is a flowchart showing an operation sequence in the microcomputer, and FIG. 16 is a diagram showing the output of the front wheel suspension sensor and the output of the rear wheel suspension sensor. FIG. 17 is an explanatory diagram showing a conversion value between a suspension sensor displacement amount and a vehicle body displacement distance. In the drawings, the same reference numerals as those in FIGS. 6 to 12 denote the same components.

Each of the displacement detectors 1 and 2 in the second example
As shown in FIGS. 13 and 14, are mounted on a suspension arm (not shown) of a front wheel portion and a suspension arm (not shown) of a rear wheel portion of the vehicle body C, respectively. It comprises suspension sensors 1- and 2- which detect and output and output the respective outputs to the microcomputer 3A as detection signals e and f. Each of the above-mentioned suspension sensors 1 and 2 detects the amount of displacement of each suspension arm and outputs an analog voltage, respectively, and a so-called volume that outputs the output of each analog voltage as detection signals e and f. Type sensor. The middle point of the above-mentioned volume is set so as to be just about half of the total resistance value when there is no loading. This is to make it correspond to the vehicle body inclination during traveling. The microcomputer 3A in the second example includes a counter, a D / A converter, an A / D
And a detection signal e, f from each of the suspension sensors 1-, 2-.
Input (sampling) at a constant cycle of 0 msec and A /
D conversion is performed.

Next, the operation of the automatic optical axis angle adjusting device of the second example will be described with reference to the operation flowchart of the microcomputer 3A of FIG. First, at (1), when the power is turned on to the optical axis angle automatic adjustment device, the microcomputer 3A, as shown in FIG.
Outputs from the above suspension sensors 1- and 2- are input as detection signals e and f at a constant period of 10 msec and are A / D converted. Fig. 15- '"Reading front wheel suspension sensor output at regular intervals" Reading rear wheel suspension sensor output at regular intervals.

Next, proceed to the same manner as in the first example described above.
A measurement number (number of times) determination process is performed. Fig. 15-"Is N data stored?"

The measured number of the detection signals e and f is 10
When the number is reached, go to 'and', and the following equation (7)
And (8), that is, Vf = (Vf1 + Vf2 +... + Vf9 + Vf10) / 10 (7) Vr = (Vr1 + Vr2 +... + Vr9 + Vr10) / 10 (8) Average value of the displacement amount of the suspension arm of the vehicle, and the average value of the displacement amount between the front part of the vehicle body and the road surface G) and the output average value Vr of the rear wheel suspension sensor 2 (the displacement amount of the suspension arm of the rear wheel portion). (The average value of the displacement amounts between the rear portion of the vehicle body and the road surface G). Fig. 15- '"Average of N front wheel suspension sensor outputs" Fig. 15-'"Average of N rear wheel suspension sensor outputs".

Then, the process proceeds to ′, and the front and rear inclination angle θ ° of the vehicle body C is calculated from the front wheel suspension sensor output average value Vf and the rear wheel suspension sensor output average value Vr as follows:
It is calculated based on the conversion chart of FIG. FIG. 15- ′ “Calculation of body inclination”.

FIG. 17 of the above conversion diagram shows the displacement amount of the suspension sensor (ie, the displacement amount between the output average value Vf of the front wheel suspension sensor and the average output value Vr of the rear wheel suspension sensor) and the displacement of the vehicle body C in the front-rear direction. It is a conversion figure with distance. The converted value of the displacement of the suspension sensor and the displacement distance of the vehicle body C in the front-rear direction is calculated from the data collection and analysis results, and is stored in the microcomputer 3A as a conversion formula of the following formula (9). That is,
The difference (displacement amount) between the front wheel suspension sensor output average value Vf and the rear wheel suspension sensor output average value Vr is represented by Vf
−Vr = Vz, and assuming that the value obtained by converting the difference Vz into the displacement distance of the vehicle body C in the front-rear direction is P, and the inclination α between P and Vz, the conversion formula P = αVz [m] (9) holds. . From the conversion formula (9), the above-described conversion diagram of FIG. 17 is obtained.

Here, assuming that the wheel base is X'm, the vehicle body inclination angle θ ° is: tan θ = P / X ′ (10) As a result, θ = tan ⁻¹ (P / X ′) [°] (11)

Then, the procedure proceeds to step S3, where the optical axis angle set value voltage d0 corresponding to the vehicle body inclination angle θ ° calculated as described above is obtained.
To d6 as the setting signal c to the right motor control unit 4 and the left motor control unit 5, respectively. FIG. 15— “Output of Optical Axis Angle Set Value Voltage” Then, similarly to the above-described first example, the operation of the vehicle speed detection unit 8 and the left and right motor control units 4 and 5 and the left and right actuators 6 and 7 stops the vehicle, Suitable for driving conditions, and
The vertical optical axis angles of the headlights RH and LH corresponding to the calculated front and rear inclination angles θ ° of the vehicle body C can be automatically adjusted. In particular, since the second example uses the suspension sensors 1-2 as the displacement amount detection units 1 and 2, the detection of the displacement amount at the front part and the rear part of the vehicle body C requires no The effect is not affected by the environment.

[0036]

However, in the above-described apparatus for automatically adjusting the optical axis angle of a headlight for a vehicle, when the vehicle speed detection unit 8 is disconnected, the state of the vehicle stopped and the state of the vehicle running are determined. Because the headlights RH, LH are not suitable for stopping and running the vehicle,
It is not adjusted to the angle corresponding to the calculated front-back tilt angle θ ° of the vehicle body C. As a result, the oncoming vehicle may be dazzled or the visibility of the own vehicle may be reduced. Further, since no means is provided for warning a driver, a passenger, or the like (hereinafter, simply referred to as a driver) that the vehicle speed detecting unit 8 is disconnected, even if the vehicle speed detecting unit 8 is disconnected, Cannot be warned.

The present invention is provided with a so-called disconnection warning function of the vehicle speed detecting unit, which can return the optical axis angle to the initial aiming position and maintain the same when the vehicle speed detecting unit is disconnected, and can activate the warning unit. An object of the present invention is to provide a device for automatically adjusting the optical axis angle of a vehicle headlamp.

[0038]

In order to achieve the above-mentioned object, the present invention is provided with a warning section for warning a disconnection state of a vehicle speed detecting section. A control function of outputting to the actuator an optical axis angle setting control signal of an initial aiming position for returning and holding the optical axis angle to the initial aiming position, and a control function of outputting a warning signal for activating the warning unit to the warning unit. Is provided in the control means.

As a result, in the apparatus for automatically adjusting the optical axis angle of a vehicle headlamp according to the present invention, when the vehicle speed detecting section is disconnected, the control means judges the disconnection state of the vehicle speed detecting section, and the initial aiming is performed by the control means. An optical axis angle setting control signal for the position is output to the actuator, and a warning signal is output to the warning unit. For this reason, since the optical axis of the headlight is returned to and held at the initial aiming position, there is no danger of dazzling the oncoming vehicle or reducing the visibility of the own vehicle.
In addition, the disconnection state of the vehicle speed detection unit is warned by the driver.

[0040]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Two embodiments of the automatic headlight angle adjusting apparatus for a vehicle headlamp according to the present invention will be described below with reference to FIGS. 1 to 4 show a first embodiment of an automatic optical axis angle adjusting apparatus for a headlight for a vehicle according to the present invention. In the drawings, the same reference numerals as those in FIGS. 6 to 17 denote the same components. In the first embodiment, each of the displacement detectors 1 and 2 is composed of a suspension sensor.

The apparatus for automatically adjusting the optical axis angle of a vehicle headlamp according to the first embodiment of the present invention includes a warning lamp 9 as a warning unit for warning a disconnection state of the vehicle speed detection unit 8. This warning lamp 9
Are arranged at positions where the driver can easily see them. On the other hand, the microcomputers 3 and 3A include a vehicle speed detecting unit 8.
When the disconnection state is determined, the optical axis angle setting control signal h of the initial aiming position for returning and holding the optical axis angle to the initial aiming position is output to the actuators 6 and 7 via the left and right motor controllers 4 and 5. A control function is provided. The above-mentioned initial aiming position refers to a position where the optical axis control angle is 0 ° in FIG. As a result, the optical axis angle setting control signal h of the initial aiming position output to the actuators 6 and 7 via the left and right motor controllers 4 and 5
Corresponds to the set value voltage d3 in FIG. In addition, the microcomputers 3 and 3A have a control function of outputting a warning signal i for turning on the warning lamp 9 to the warning lamp 9 when the disconnection state of the vehicle speed detection unit 8 is determined. Further, the microcomputers 3 and 3A are also provided with a reset function for turning off the lit warning lamp 9 after the disconnection of the vehicle speed detection unit 8 is repaired.

Here, the point in time when the microcomputer 3, 3A determines the disconnection of the vehicle speed detector 8 will be described with reference to FIGS. First, when the vehicle speed detection unit 8 is in a normal state, when the vehicle is running, a pulse signal that changes according to the vehicle speed is a vehicle speed signal g.
Is output to the microcomputers 3 and 3A. When the vehicle is stopped, a signal at the “LO” level is set as the vehicle speed signal g to the microcomputers 3 and 3.
A is output to A. On the other hand, when the vehicle speed detection unit 8 is in a disconnected state, even when the vehicle is running,
Even when the car is stopped, both are "LO"
The level signal is output to the microcomputers 3 and 3A as the vehicle speed signal g. As a result, the microcomputers 3 and 3A need only perform the disconnection determination of the vehicle speed detection unit 8 when the "LO" level vehicle speed signal g is output from the vehicle speed detection unit 8.

Next, conditions for determining that the vehicle speed detecting section 8 is in a disconnected state will be described. That is, the vehicle speed detector 8
The control of returning the optical axis angle to the initial aiming position and maintaining the optical axis angle by determining that the vehicle is in the disconnection state is performed in order to prevent dazzling of the oncoming vehicle and decrease of the visibility of the own vehicle. It is. Thus, it is necessary at least when the vehicle is in a running state to determine that the wire is broken and perform the above-described control. As a result, it is necessary to determine the disconnection of the vehicle speed detection unit 8 while the vehicle is running.

Further, the basis for judging whether the vehicle is stopped or running from the inclination of the vehicle body C will be described with reference to FIG. First, when the vehicle is stopped and the vehicle is idle, the detection values of the suspension sensors of the displacement amount detection units 1 and 2 are constant. Further, when the occupant or the load changes, the detection value of the suspension sensor of each of the displacement amount detection units 1 and 2 changes, but after a certain period of time, it calms down with the value accompanying the change of the occupant and the load. It will be constant. On the other hand, when the car is running, when accelerating, when decelerating,
In the case of traveling on a slope, the detection values of the suspension sensors of the displacement amount detection units 1 and 2 greatly change. Further, when traveling at a constant speed, the inclination of the vehicle body C does not change so much, but the detection values of the suspension sensors of the displacement amount detection units 1 and 2 change small. As a result, when the inclination of the vehicle body C changes greatly or small within a short time,
It can be determined that the car is running.

Next, the operation control of the apparatus of the present invention in the first embodiment will be described with reference to the flowchart of FIG. First, in (11), based on the vehicle speed signal g output from the vehicle speed detection unit 8, the microcomputer 3,
In 3A, it is determined whether or not the vehicle speed detection unit 8 performs the disconnection determination. As shown in FIG. 3, when the vehicle speed signal g of the pulse signal is output from the vehicle speed detection unit 8, the vehicle speed detection unit 8 does not perform the disconnection determination, determines that the vehicle speed detection unit 8 is normal, and proceeds to (12). The automatic adjustment of the optical axis angle (auto leveling control during traveling) is performed. On the other hand, when the vehicle speed signal g of the "LO" level signal is output from the vehicle speed detection unit 8, the disconnection of the vehicle speed detection unit 8 is determined, and the process proceeds to (13). FIG. 1- (11) “Is vehicle speed pulse output?” FIG. 1- (12) “Same control as in FIGS. 8 and 15”.

Next, in (13), at regular time intervals (N
(Every second), the vehicle body inclination angle θ ° is calculated, and then (14)
In, it is determined whether or not the calculated vehicle body inclination angle θ ° is the same as the previously calculated vehicle body inclination angle θ °. In the same case, the vehicle is stopped (the situation indicated by arrows i to iv in FIG. 2), and the vehicle speed detection unit 8 determines that the vehicle is normal (1).
Proceeding to 5), the automatic adjustment of the optical axis angle (auto leveling control during stopping) is performed. On the other hand, if different, (1
Proceed to 6). Fig. 1- (13) "Calculation of vehicle body tilt every N seconds" Fig. 1- (14) "Is the same value as the previous value?" Fig. 1- (15) "Same control as in Figs. 8 and 15".

Then, in (16), it is determined whether or not the same vehicle body inclination angle θ ° has continued for a predetermined time (N × (S−1) seconds). If it continues, it means that the occupant and the load have changed, the car is stopped (the situation shown by arrows v and vi in FIG. 2), and the vehicle speed detection unit 8 determines that it is normal (1).
Proceeding to 7), automatic adjustment of the optical axis angle is performed. FIG. 1- (16) “Is S the same value continued in P?” FIG. 1- (17) “Same control as in FIGS. 8 and 15”.

In the above (16), if the same vehicle body inclination angle θ ° does not continue for a predetermined time (N × (S−1) seconds), the vehicle is running (arrows vii to x in FIG. 2).
ii), the vehicle speed detection unit 8 determines that the wire is broken, and proceeds to (19) and (20) via (18). This (1
In step 9), the optical axis angle setting signal h at the initial aiming position is output to the actuators 6 and 7 via the left and right motor controllers 4 and 5, and the optical axis angle is returned to the initial aiming position and held. In (20), a warning signal i is output to the warning lamp 9, and the warning lamp 9 is turned on. FIG. 1- (18) “Disconnection” FIG. 1- (19) “Output of optical axis angle set value voltage d3” FIG. 1- (20) “Warning lamp on”.

As described above, the apparatus for automatically adjusting the optical axis angle of a vehicle headlamp according to the present invention in this embodiment, when the disconnection state of the vehicle speed detector 8 is determined, the microcomputer 3 or 3A sends the initial aiming position. Is output to the actuators 6 and 7, the optical axes of the headlights RH and LH are returned to and held at the initial aiming position θ °, causing dazzling to oncoming vehicles, There is no fear that the visibility is reduced. The microcomputers 3, 3
Since the warning signal i is output from A to the warning lamp 9, the disconnection state of the vehicle speed detector 8 is warned by the driver.

In particular, in this embodiment, the disconnection judgment of the vehicle speed detecting unit 8 is performed by the output from the vehicle speed detecting unit 8 and the microcomputers 3 and 3A.
There is no need to provide a separate disconnection determination circuit for the vehicle speed detector 8. As a result, the number of parts and cost can be reduced.

FIG. 5 shows a second embodiment of the apparatus for automatically adjusting the optical axis angle of an automotive headlamp according to the present invention. In the drawings, the same reference numerals as those in FIGS. 1 to 4 and 6 to 17 denote the same components. In the second embodiment, each of the displacement detectors 1, 2
Uses a suspension sensor.

The apparatus for automatically adjusting the optical axis angle of a vehicle headlamp according to the second embodiment of the present invention detects the disconnection state of the vehicle speed detector 8 by detecting the vehicle body front displacement amount detector 1 (or the vehicle body rear displacement amount detector). The determination is made based on the data detected by the second unit. That is, when the difference T between the maximum value and the minimum value of the plurality (P) of data detected by the vehicle body front displacement amount detection unit 1 is larger than the set value S, the vehicle travels. It can be determined that it is in the middle state (see FIG. 2).

Next, the operation control of the device of the present invention in the second embodiment will be described with reference to the flowchart of FIG. First, in (11), when a pulse signal is output from the vehicle speed detection unit 8, the vehicle speed detection unit 8 determines that it is normal and proceeds to (12) to perform automatic adjustment of the optical axis angle.
On the other hand, when the “LO” level signal is output from the vehicle speed detection unit 8, the process proceeds to (21), and the disconnection of the vehicle speed detection unit 8 is determined. FIG. 5- (11) “Is vehicle speed pulse output?” FIG. 5- (12) “Same control as in FIGS. 8 and 15”.

Next, in (21), at regular time intervals (N
(Every second), the data detected by the vehicle body front displacement detecting section 1 is read, and subsequently, in (22), it is determined whether or not a predetermined number (P) of the read data has accumulated. . When the vehicle is not accumulated, the vehicle is stopped (the situation shown by arrows i to iv in FIG. 2), and the vehicle speed detection unit 8
Is determined to be normal, the process proceeds to (15), and the automatic adjustment of the optical axis angle is performed. On the other hand, if it has accumulated, the process proceeds to (23). FIG. 5- (21) “Reading of vehicle body front displacement amount detecting section every N seconds” FIG. 5- (22) “P accumulated?” FIG. 5- (15) “Same control as in FIGS. 8 and 15”.

Then, in (23), the difference T between the maximum value and the minimum value of the P data is calculated, and then (2)
In 4), it is determined whether the difference T is larger or smaller than the set value S. If it is small, it means that the occupant and the load have changed, and the vehicle is stopped (arrows v, v in FIG. 2).
i), the vehicle speed detection unit 8 determines that the vehicle speed is normal, and proceeds to (17) to perform automatic adjustment of the optical axis angle. FIG. 5- (23) “Calculation of maximum value−minimum value = T of P data” FIG. 5- (24) “Is set value S <T?” FIG. 5- (17) “FIG. Same control ".

If the difference T is larger than the set value S in the above (24), the vehicle is running (the situation indicated by arrows vii to xii in FIG. 2), and the vehicle speed detector 8 Is determined to be broken (18), (19),
Proceed to (20). Fig. 5- (18) "Disconnection" Fig. 5- (19) "Output of optical axis angle set value voltage d3" Fig. 5- (20) "Warning lamp lighting".

As described above, the apparatus for automatically adjusting the optical axis angle of an automotive headlamp according to the second embodiment of the present invention can achieve the same functions and effects as those of the apparatus of the first embodiment. In particular, in the device according to the second embodiment, the disconnection determination of the vehicle speed detection unit 8 is performed by setting the difference T between the maximum value and the minimum value of the P data detected by the vehicle body front displacement amount detection unit 1. Since the determination is made based on whether the value is greater than the value S, erroneous determination is prevented as much as possible.

That is, the set value S is as follows: (a) Fluctuation of the detection signal (analog voltage) of the vehicle body front displacement amount detecting section 1. (B) The value fluctuates as the resolution of A / D conversion when the detection signal (analog voltage) of the vehicle body front displacement amount detection unit 1 is input to the microcomputers 3 and 3A increases. (C) At the time of A / D conversion when the detection signal (analog voltage) of the vehicle body front displacement amount detection unit 1 is input to the microcomputers 3 and 3A, the value changes if it is a threshold value. Is determined in consideration of the situation. For example, the voltage width of one count when the reference voltage is 5 V is 1/25 in the case of 8 bits.
6 × 5V = 0.02V, and for 10 bits, 1 /
1024 × 5V = 0.005V. As described above, when the accuracy is improved, the width of the threshold value for one count and one count becomes narrower, so that the set value S is set to (a), (b),
If the determination is made in consideration of the situation (c), erroneous determination is prevented.

In the above-described embodiment, each of the displacement detectors 1 comprising a suspension sensor,
2 is used, but the present invention may use each of the displacement amount detection units 1 and 2 configured by an ultrasonic sensor or the like.

[0060]

As described above, in the apparatus for automatically adjusting the optical axis angle of a vehicle headlamp according to the present invention, when the vehicle speed detecting section is disconnected, the control means judges the disconnection state of the vehicle speed detecting section.
The control unit outputs an optical axis angle setting control signal of the initial aiming position to the actuator, and outputs a warning signal to the warning unit. For this reason, since the optical axis of the headlight is returned and held at the initial aiming position,
There is no danger of dazzling the oncoming vehicle or reducing the visibility of the own vehicle. In addition, the disconnection state of the vehicle speed detection unit is warned by the driver.

[Brief description of the drawings]

FIG. 1 is a flowchart of an operation sequence in a microcomputer showing a first embodiment of a device for automatically adjusting an optical axis angle of a vehicle headlamp according to the present invention.

FIG. 2 is an explanatory diagram showing a correlation between a stop and a running state of a vehicle, a vehicle body inclination, a vehicle body inclination calculation timing, a normal output and a disconnection output of a vehicle speed detection unit, and control of a microcomputer.

FIG. 3 is an explanatory diagram showing a correlation between a state of a vehicle speed detection unit, a state of a vehicle, an output of the vehicle speed detection unit, a disconnection determination of a microcomputer, a result, and control.

FIG. 4 is a block diagram of an automatic optical axis angle adjusting device for a headlight for a vehicle according to the present invention.

FIG. 5 is a flowchart of an operation sequence in the microcomputer showing the second embodiment of the automatic headlight angle adjusting device for a vehicle headlamp according to the present invention.

FIG. 6 is a block diagram showing a first prior art apparatus for automatically adjusting the optical axis angle of a vehicle headlamp;

FIG. 7 is a schematic diagram of a vehicle equipped with the first prior art vehicle headlight automatic optical axis angle adjusting device in FIG. 6;

FIG. 8 is a flowchart of an operation sequence in the microcomputer.

FIG. 9 is a signal waveform diagram illustrating an operation of each unit of each displacement amount detection unit.

FIGS. 10A and 10B are waveform diagrams showing a state in which ten detection signals from each displacement amount detection unit are accumulated in the microcomputer.

FIGS. 11A and 11B are waveform charts showing average values of detection signals from each of the displacement amount detection units accumulated in a microcomputer by 10 pieces.

FIG. 12 is an explanatory diagram showing a correlation among a vehicle body tilt average value, a set value voltage, and an optical axis control angle.

FIG. 13 is a block diagram showing a second prior art apparatus for automatically adjusting the optical axis angle of a vehicle headlamp.

FIG. 14 is a schematic view of a vehicle equipped with the second prior art vehicle headlight automatic optical axis angle adjusting device in FIG. 13;

FIG. 15 is a flowchart showing an operation sequence in the microcomputer.

FIG. 16 is an explanatory diagram showing the timing at which the output of the front wheel suspension sensor and the output of the rear wheel suspension sensor are read into the microcomputer at regular intervals.

FIG. 17 is an explanatory diagram showing a converted value of a suspension sensor displacement amount and a vehicle body displacement distance.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Body displacement amount detection part, 2 ... Body displacement amount detection part, 1-, 2 -... Ultrasonic sensors, 1-, 2 -...
Transmission unit (transmission circuit), 1-, 2 -... Reception unit (reception circuit), 1-, 2 -... Suspension sensor, 3, 3
A: microcomputer (control means), 4, 5: motor control unit (control means), 6, 7: actuator (DC
8) Vehicle speed detecting section, 9 ... Warning lamp (warning section), a, b, e, f ... Detection signal, c ... Setting signal, c '... Control signal (optical axis angle setting control signal) ), G: vehicle speed signal, h: optical axis angle setting control signal of initial aiming position, i: warning signal, s1, s
2: Position signal, d0 to d6: Optical axis angle set value voltage, θ °
Initial aiming position, C: car (body), G: road surface,
L / A: Actuator, RH, LH: Headlight, X: Distance between front and rear ultrasonic sensors, X ': Wheelbase.

Claims (3)

[Claims] 1. A device for automatically adjusting a vertical optical axis angle of a headlight corresponding to a stop or running state of an automobile and corresponding to an inclination of a vehicle body in front and rear, comprising: A vehicle body front displacement detector that detects a displacement and outputs the detection signal as a detection signal; a vehicle body rear displacement detector that detects a displacement between the vehicle rear and the road surface and outputs the detection signal as a detection signal; A vehicle speed detection unit that outputs the state as a vehicle speed signal, a vehicle speed signal from the vehicle speed detection unit is input, and each detection signal from each of the displacement amount detection units is input to calculate a vehicle body inclination value, Stop means of the car, control means for outputting an optical axis angle setting control signal suitable for the state of running and corresponding to the vehicle body inclination value, inputting the optical axis angle setting control signal from the control means, and setting the optical axis angle An actuator that controls In the apparatus for automatically adjusting the optical axis angle of a vehicle headlamp, there is provided a warning unit for warning a disconnection state of the vehicle speed detection unit, and when the control unit determines a disconnection state of the vehicle speed detection unit, A control function of outputting the optical axis angle setting control signal of the initial aiming position for returning and holding the axis angle to the initial aiming position to the actuator, and a control function of outputting a warning signal for operating the warning unit to the warning unit A device for automatically adjusting the optical axis angle of an automotive headlamp, comprising: 2. A vehicle speed signal output from the vehicle speed detection unit includes a pulse signal output when the vehicle is in a running state,
A "LO" level signal that is output when the vehicle is stopped and when the vehicle is disconnected. The control means outputs a "LO" level signal when the vehicle speed detection unit outputs a "LO" level signal. At the time when the calculated vehicle body inclination value is different from the previous vehicle body inclination value, when a plurality of the same values do not continue in a predetermined number of calculated vehicle body inclination values, The vehicle headlight according to claim 1, wherein the vehicle speed detection unit determines that the vehicle is in a disconnected state, and outputs an optical axis angle setting control signal of the initial aiming position and the warning signal, respectively. Automatic optical axis angle adjustment device. 3. A vehicle speed signal output from the vehicle speed detection unit includes a pulse signal output when the vehicle is running,
A "LO" level signal that is output when the vehicle is stopped and when the vehicle is disconnected. The control means outputs a "LO" level signal when the vehicle speed detection unit outputs a "LO" level signal. A detection signal from the vehicle body front displacement amount detection unit or a detection signal from the vehicle body rear displacement amount detection unit, and when a predetermined number of the read detection signals are accumulated, the maximum value of the predetermined number of detection signals And the minimum value is calculated, and when the calculated difference is larger than a predetermined value, the vehicle speed detection unit is determined to be in a disconnected state, and the optical axis angle setting control signal of the initial aiming position and the warning The automatic optical axis angle adjusting device for a vehicle headlamp according to claim 1, wherein a signal is output.