JPH02182549A - Light distribution correction device for motorcycle headlights - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a light distribution correction device for a motorcycle headlamp that can always keep the light distribution of the headlight horizontal with respect to the road surface. be.

[Conventional technology]

2. Description of the Related Art Conventionally, it has been known that a headlight (headlamp) of a two-wheeled vehicle is rotated around an optical axis according to the inclination angle of the vehicle body. In other words, when a two-wheeled vehicle turns left or right, the vehicle body leans against the road surface, but if the headlights also lean at this time, the normal light distribution pattern will not be obtained and sufficient light will not be provided in the direction of the turn. At the same time, a situation arises in which oncoming vehicles are dazzled. Therefore, it is desirable to rotate the headlight in the direction opposite to the direction of inclination depending on the inclination angle of the vehicle body.

FIG. 4 shows an example in which the above-mentioned inclination angle detection means is attached to a motorcycle, in which the ultrasonic sensor 1 is attached to the axle of the wheel 2. In addition, in the figure, 3 is a headlight, and 4 is a road surface.

In a motorcycle equipped with such an ultrasonic sensor 1, when the vehicle body leans when turning left or right, the detection value of the ultrasonic sensor 1 that detects the distance to the road surface 4 changes,
The tilt angle is detected from this amount of change. Although not shown, the headlight 3 is rotated around the optical axis in a direction opposite to the inclination direction by an optical axis driving means according to the inclination angle.

Thereby, the light distribution of the headlights 3 is kept horizontal to the road surface 4.

[Problem to be solved by the invention]

However, in the conventional light distribution correction means for motorcycles as described above, the ultrasonic sensor is placed only on one side, so if there is an obstacle such as a curb between the sensor and the road surface, or if the wheels are If the vehicle does not touch the ground, the angle of inclination of the vehicle is incorrectly detected, causing the headlights to malfunction.Also, since the sensor is mounted on the axle, there is a large impact force from uneven road surfaces, which causes noise due to vibration. There have been problems in that this may occur or the sensor may be damaged.

This invention was made with attention to these problems, and it provides a headlight for motorcycles that can detect the angle of inclination without error, prevents the headlight from malfunctioning, and prevents the effects of vibration and damage to the sensor. The purpose is to obtain a light distribution correction device.

(Means for Solving the Problems) The light distribution correction device for a motorcycle headlamp of the present invention detects the inclination angle of the vehicle body based on the output from ultrasonic sensors installed on both left and right sides of the vehicle body of the motorcycle, The system is configured to adjust the rotation angle of the headlights according to the detected tilt angle of the vehicle body, and the tilt angle is detected by comparing the outputs from the left and right ultrasonic sensors using a differential amplifier. By doing this,
Furthermore, the detection signal of the tilt angle of the heavy body and the detection signal of the rotation angle of the headlamp are compared by a differential amplifier to adjust the rotation angle of the headlamp.

(Function) In the light distribution correction device for a motorcycle headlamp of the present invention,
Ultrasonic sensors are installed on both the left and right sides of the vehicle body, so the tilt angle can be accurately detected regardless of obstacles.
Also, it is not affected by wheel vibration.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

Fig. 1 is a diagram showing the running state of a motorcycle equipped with the light distribution correction device according to the present invention, in which Fig. 1(a) shows the state when the motorcycle is running straight and horizontally, and Fig. 1(b) shows the state when the motorcycle is running on the right side. Each shows the state when the vehicle is tilted while turning left.

In the figure, 1a and 1b are ultrasonic sensors installed on both left and right sides of the vehicle body, 2 is a wheel, 3 is a headlight (headlamp), and 4 is a road surface.

The left and right ultrasonic sensors 1a and 1b are installed with their ultrasonic emission ports facing the road surface 4, and the outputs of these ultrasonic sensors Ia and 1bh1 detect the inclination angle of the vehicle body. The headlight 3 is configured to adjust the rotation angle of the headlight 3 according to the detected inclination angle. Here, both sensors la and lb each measure the distance to the road surface 4, and at that time, they output a signal with a voltage level corresponding to the measured distance, and the difference between these outputs is detected. Detects the tilt angle of the vehicle body. At this time, both sensors la
, lb is "0" when the heights of the left and right sensors Ia and Ib are equal, that is, when the vehicle body is horizontal with respect to the road surface 4 as shown in FIG. When the vehicle body is tilted as shown in FIG. 1(b), the value is "+" or "-" depending on the tilt angle. When the vehicle body tilts, the headlight 3 is rotated in the direction of arrow A in the figure, that is, in the direction opposite to the tilt, based on the "+" or "-" output.

Thereby, the light distribution of the headlights 3 is kept horizontal to the road surface 4.

FIG. 2 is a block diagram showing an example of the circuit configuration of the light distribution correction device. In the figure, 5 is 40 KH for ultrasonic oscillation.
6 is a clock generator that generates a reference clock; 7a and 7b are 0 and 5 m;
A multivibrator that generates a one-shot signal of 5ec, 8a and 8b a mask circuit that generates a mask signal, 9
a and 9b are AND gates, 10a and Job are AND gates 9a.

amplifiers that amplify the signals applied from 9b to the ultrasonic sensors la and lb; lla and llb are amplifiers that amplify the output signals (received signals) from the ultrasonic sensors la and lb; 12a;
12b is a detector, 13a.

13b is a comparator, 14a, 14b are timers, 15a, 1
5b is a D/A (digital/analog) comparator, 16 is a differential amplifier, 17 is a potentiometer that detects the rotation angle of the headlight 3, 18 is a differential amplifier, 19a
, 19b is a comparator, and 20 is a driver that drives the motor 21 to rotate the headlight 3.

In the above circuit, the left and right ultrasonic sensors la.

■The tilt angle of the vehicle body is detected by comparing the output from b with the differential amplifier 16, and the detection signal (output signal of the differential amplifier 16) is compared with the rotation angle of the headlight 3. A differential amplifier 18 compares the detection signal (output signal of the potentiometer 17) to adjust the rotation angle of the headlight 3 by 51 degrees. FIG. 3 shows the signal waveforms of each part (a to h) in FIG. 2, and here is a timing chart of the sensor 1a on one side.

That is, a one-shot signal C is obtained from the reference clock b in FIG. Then, input the H2 pulse and this C one-shot signal to the AND gate 9a at 40 of a,
The output signal e is amplified and the ultrasonic sensor 1
Apply to a.

Further, the received signal f from the ultrasonic sensor 1a is amplified and then manually inputted to the detector 12a. At this time, the received signal of f includes the emitted wave component 1 and the reflected wave component 2 from the path wB4.
Since both components are included, the detected signal of g is detected by comparator 1.
At step 3a, it is compared with the mask signal d, and only a signal exceeding the level of the mask signal, that is, a comparison signal h, which is a reflected wave component, is extracted. The next-stage timer 14a operates using the one-shot signal of C as a trigger (TR) signal, the comparison signal of h as a clear (CL) signal, and the reference clock of a as a clock (CK). The time from the emission of the sound wave signal to the reception of the reflected wave is measured. The time data is stored in the next stage D/A converter 15a.
is converted into a voltage level signal by

On the other hand, regarding the sensor 1b on the opposite side, signal processing similar to that described above is performed in each section, and a voltage level signal corresponding to the distance between the sensor Ib and the road surface 4 is output from the D/A converter 15b. Then, these voltage level signals are input to the differential amplifier PJ16, and a differential output corresponding to the inclination of the vehicle body is obtained from the differential amplifier 16.

Here, the above-mentioned light distribution correction device is provided with a potentiometer 17 so as to apply a divided voltage according to the rotation angle of the drive motor 21 of the headlight 3 rotating around the optical axis. However, the differential amplifier 16 is used so that the output of the potentiometer 17 and the differential output become the same voltage output when the rotation angle of the headlight 3 and the angle of inclination of the vehicle body in the opposite direction respectively match. The amplification factor etc. are set. The output of the potentiometer 17 and the output of the differential amplifier 16 are input to a differential amplifier 18, and the output of the differential amplifier 18 is compared with a window voltage by comparators 19a and 19b. Based on this comparison result, by rotating the motor 21 forward or reverse (reversing) via the driver 2°, the differential amplifier is always activated! The output of 8 is controlled to fit within the window. As a result, even if the vehicle body is tilted, the light distribution of the headlights 3 will always be adjusted to the road surface 4.
is kept horizontal to.

In this way, the light distribution pattern of the two-wheeled vehicle can always be properly controlled, but in this case, the ultrasonic sensors la, lb
Since these are provided on both the left and right sides, the inclination angle of the vehicle body can be detected correctly without being erroneously detected, and the headlights 3 will not malfunction. That is, both sensors la,
When the output from one of the lb sensors is constant, the headlight 3 remains unchanged even if the output from the other sensor changes.
The light distribution will not be corrected. For example, even if an obstacle such as a curb is present under one sensor while the vehicle is driving, the headlights 3 will not rotate. Furthermore, since the ultrasonic sensors la and lb are not provided on the axle, it is possible to prevent the effects of vibrations caused by uneven road surfaces and damage to the sensors la and lb. Furthermore, in the example of FIG. 2, both sensors la,
Since the lb differential output is used, the influence of vertical movement of the vehicle body can also be ignored.

(Effects of the Invention) As described above, according to the present invention, since the ultrasonic sensors are installed on both the left and right sides of the vehicle body, the tilt angle of the vehicle body can be detected without error, the malfunction of the headlights is eliminated, and This has the effect of preventing the influence of wheel vibration and damage to the sensor, and by using a differential amplifier, it is possible to detect the tilt angle more accurately.

[Brief explanation of the drawing]

Figures 1 to 3 are diagrams showing an embodiment of the present invention.
FIG. 1 is a normal image showing a running state of a two-wheeled vehicle, FIG. 3 is a signal waveform chart of each part of FIG. 2, and FIG. 3 is a front view showing a conventional example. la, lb --- Ultrasonic sensor 3 --- Headlight (headlight) 16 ---
-Differential amplifier 17-----Potentiometer 18-=-Differential amplifier 21----Motor

Claims (3)

[Claims] (1) The angle of inclination of the vehicle body is detected by the output from ultrasonic sensors installed on both the left and right sides of the motorcycle body, and the rotation angle of the headlight is adjusted according to the detected angle of inclination of the vehicle body. A light distribution correction device for a motorcycle headlamp, which is characterized by: (2) The light distribution correction device for a motorcycle headlamp according to claim 1, wherein the inclination angle of the vehicle body is detected by comparing the outputs from the left and right ultrasonic sensors using a differential amplifier. . (3) The rotation angle of the headlamp is adjusted by comparing the detection signal of the tilt angle of the vehicle body and the detection signal of the rotation angle of the headlamp using a differential amplifier. The light distribution correction device for a motorcycle headlamp described above.