JP2003341421A - Light distribution control device of vehicular headlamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light distribution control device of a vehicular headlamp manufacturable at low cost regardless of the type of a vehicle, and hardly influenced by a road surface condition such as irregularity. <P>SOLUTION: Lighting and lighting-out of additional lighting lamps 4 and 5 for irradiating the turning direction of a light distribution pattern 6 by headlamps 2 and 3 in curve traveling of the vehicle 1 is controlled based on the output signal from an acceleration sensor 12. The acceleration sensor 12 is built in an arithmetic control part 13. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light distribution control device for a vehicle headlamp.

[0002]

2. Description of the Related Art Conventionally, when driving a vehicle on a left or right curve,
When driving in a curve on a winding road, if the field of view in front is dark, it is not convenient for driving.Therefore, the curve traveling is detected from the steering angle of the steering wheel, and the headlamp irradiation angle in the curve traveling direction is detected in front of the traveling direction. There is known a light distribution control device for a vehicle headlamp, which is designed to widen the vehicle.

In this conventional vehicle headlamp light distribution control device, when the steering angle of the steering wheel becomes equal to or greater than the reference steering angle for starting lighting, the additional lighting lamp is turned on and the steering angle of the steering wheel is turned on. While the start judgment reference steering angle is greater than or equal to and less than the predetermined angle,
The additional lighting lamp is swiveled (oscillated) so that the irradiation angle of the additional lighting lamp increases in proportion to the rudder angle, and when the rudder angle is at or above the predetermined angle, the swivel is stopped and additional lighting is performed. Control is performed to fix the irradiation angle of the lamp (for example, Japanese Patent Laid-Open No. 2000-195312).

[0004]

In this conventional light distribution control device, a very expensive and highly accurate rudder angle detection sensor must be used. Therefore, the light distribution control device becomes expensive accordingly. Further, since the vehicle type to which the steering angle detecting sensor is attached is limited, the vehicle type to which the light distribution control device can be attached is also limited accordingly.

Further, in this conventional light distribution control device, the steering angle by the steering wheel operation is detected by using a highly accurate steering angle detection sensor, and the additional lighting lamp is turned on / off based on the steering angle of the steering wheel operation. It also controls the irradiation angle of the additional lighting device. Therefore, when the steering wheel moves finely in the vicinity of the lighting start determination reference rudder angle according to the road surface condition such as unevenness, the movement of the steering wheel is followed to cause the additional lighting lamp to blink by repeating lighting and extinguishing. Blinking may also annoy the driver.

The present invention has been made in view of the above circumstances. The object of the present invention is not limited to a vehicle type, and can be manufactured at a low cost, and is not affected by road surface conditions such as unevenness as much as possible. It is an object of the present invention to provide a light distribution control device for a vehicle headlamp that can perform the above.

[0007]

According to a first aspect of the present invention, additional lighting lamps for additionally illuminating the front of the vehicle in the traveling direction when traveling on a curve are provided on the front surface of the vehicle at intervals in the vehicle width direction. A light distribution control device for a vehicle headlight, which detects acceleration in the vehicle width direction according to turning of the vehicle,
An acceleration sensor that outputs a detection signal, and an arithmetic control unit that controls turning on and off of the additional lighting device according to the output of the acceleration sensor, and the acceleration sensor is incorporated in the arithmetic control unit. Is characterized by.

According to a second aspect of the present invention, the arithmetic control unit is attached to the additional lighting device.

According to a third aspect of the present invention, there is provided a vehicle headlamp in which additional lighting lamps for additionally illuminating the front of the vehicle in the traveling direction when traveling on a curve are provided on the front surface of the vehicle at intervals in the vehicle width direction. In the light distribution control device, the angular velocity detection sensor that detects an angular velocity associated with the turning of the vehicle and outputs a detection signal, and controls the turning on and off of the additional lighting device according to the output of the angular velocity detection sensor. And an arithmetic control unit for
A light distribution control device for a vehicle headlamp, wherein the angular velocity detection sensor is incorporated in the arithmetic control unit.

According to a fourth aspect of the present invention, the arithmetic control unit is attached to the additional lighting device.

According to the first and third aspects of the present invention, the arithmetic control unit determines whether the vehicle is traveling, whether it is straight traveling or curved traveling based on the output signal from the acceleration sensor or the angular velocity sensor. It is determined whether the curve traveling is in the right direction or the left direction depending on the traveling direction of the vehicle, and by the determination of this arithmetic control unit, the additional lighting lamp in the direction in which the vehicle is going to turn is appropriately turned on. It can be completed in the light distribution system without using the steering angle of the steering wheel or the signal from the vehicle speed sensor. Therefore, it is possible to prevent the additional lighting lamp from being repeatedly turned on and off due to a slight movement of the handle, and the additional lighting lamp is properly turned on and off. Further, since the acceleration sensor or the angular velocity sensor is incorporated in the arithmetic control unit, the work for incorporating the acceleration sensor or the angular velocity sensor in the vehicle is unnecessary by incorporating the control circuit board in which the arithmetic control unit is formed in the vehicle. By simplifying the assembling work, an inexpensive vehicle light distribution control device is provided.

According to the second and fourth aspects of the present invention, since the control circuit board having the arithmetic control unit in which the acceleration sensor or the angular velocity sensor is incorporated can be unitized and incorporated into the additional lighting lamp in advance, the assembly is not required. It becomes easier and advantageous in cost reduction.

[0013]

FIG. 1 is a schematic view showing an example of a vehicle according to an embodiment of the present invention viewed from the front. 1
Is a vehicle, 2 is a right headlamp as a headlamp, 3 is a left headlamp as a headlamp, 4 is a right additional lighting lamp for additionally illuminating the traveling direction when the vehicle 1 is traveling to the right in a curve. Is a left additional lighting lamp for additionally illuminating the traveling direction when the vehicle 1 travels to the left in a curve.

The light distribution pattern of the vehicle 1 is shown in FIG. Light distribution patterns 7 and 8 by the right additional lighting lamp 4 and the left additional lighting lamp 5, respectively, are formed on both sides of the light distribution pattern 6 obtained by combining the right headlamp 2 and the left headlamp 3.

Here, the right additional lighting lamp 4 and the left additional lighting lamp 5 are set so that their respective irradiation axes B have an opening angle of 12 degrees with respect to the straight traveling direction A of the vehicle 1. Further, the light distribution pattern 6 and the light distribution patterns 7 and 8 are set to overlap each other. If there is no overlap between the light distribution pattern 6 and the light distribution patterns 7 and 8, both the light distribution patterns 6 and the light distribution will be immediately after the right additional lighting lamp 4 or the left additional lighting lamp 5 is turned on. This is because a dark region is generated between the patterns 7 and 8 and the formation of this dark region is prevented and the driver feels uncomfortable due to the dark region.

As shown in FIG. 3, each of the additional lighting lamps 4 and 5 includes a cylindrical housing 9a whose one end is open, and a bulb 9b supported in the housing 9a. Inside the housing 9a, a reflector 9c for directing the emitted light from the bulb 9b to the front is arranged on the back surface of the bulb 9b, and a lens 9d is attached to the front end of the housing 9a. A control circuit board 1 in which an arithmetic control unit for controlling lighting / extinguishing operations of both the additional lighting lamps 4 and 5 is formed in one housing 9a of the both additional lighting lamps 4 and 5.
0 is attached.

Right additional lighting lamp 4, left additional lighting lamp 5
The lighting and extinguishing operations of are controlled by the light distribution control device 11 shown in FIG. The light distribution control device 11 includes a headlamp switch SW1, an acceleration sensor 12, an arithmetic control unit 13, a right additional lighting lamp driver unit 14 and a left additional lighting lamp driver unit 15. The arithmetic control unit 13 is formed on the control circuit board 10 attached to the housing 9 a, and the acceleration sensor 12 is assembled to the control circuit board 10 so that the acceleration sensor 12 is incorporated in the arithmetic control unit 13. .

The acceleration sensor 12 is a known acceleration sensor such as a semiconductor G sensor utilizing the piezoresistive effect of silicon, and is provided on either the right additional lighting lamp 4 or the left additional lighting lamp 5. . The acceleration sensor 12 has a pair of output terminals, and as shown in FIG. 5, for example, outputs an output voltage Va corresponding to the acceleration R in the right direction or the clockwise direction when viewed from the driver's seat of the vehicle 1 to one output end. Then, the output voltage Vb corresponding to the acceleration L to the left, that is, the counterclockwise direction is output to the other output end. In the example shown in FIG. 5, the acceleration is proportional to the output voltage.

Since the lateral accelerations L and R, which are accelerations in the vehicle width direction, do not act on the acceleration sensor 12 when the vehicle 1 is in a stopped state or in a straight traveling state, the acceleration sensor 12 outputs an output from both of the output terminals. The voltages Va and Vb are not output.

When the vehicle 1 travels in a curve, an acceleration R or L is applied to one of the left and right sides depending on the turning direction. When the acceleration sensor 12 detects the acceleration R or L, the acceleration R or L is detected. A voltage Va proportional to the magnitudes of the accelerations R and L is applied to one of the output terminals of the acceleration sensor 12.
Alternatively, Vb is output to the arithmetic control unit 13 as the output signal K1.

The arithmetic and control unit 13 has a function of controlling turning on / off of the right additional lighting lamp 4 and the left additional lighting lamp 5 according to the output signal K1 from the acceleration sensor 12. The right additional lighting lamp 4 is driven by a drive circuit section including the right additional lighting driver section 14 and lights up. The left additional lighting lamp 5 is driven by a drive circuit section including the left additional lighting driver section 15 and lights up.

Both additional lighting lamp drivers 14 and 15
To the battery BA via the ignition switch SW2.
Electric power for each additional lighting lamp 4 and 5 is supplied from T, and each additional lighting lamp 4 and 5 is supplied from the arithmetic and control unit 13.
A control signal for driving is input.

Further, a detection signal K2 for detecting that the headlamp switch SW1 for lighting the right headlamp 2 and the left headlamp 3 is operated is inputted to the arithmetic control section 13 from the headlamp switch SW1. It

In a situation where the arithmetic control unit 13 receives the detection signal K2 notifying that the headlamp is being turned on, the additional lighting device for each additional lighting is responsive to the control signal K1 (Va, Vb) from the acceleration sensor 12. Controls turning on and off of 4 and 5. For this control, the arithmetic and control unit 13 has a memory, and the memory has a judgment reference value Va which is a judgment criterion for both lighting start and extinction start of the additional lighting lamps 4 and 5.
1 and Vb1 are stored.

The arithmetic control unit 13 compares the output signal Va corresponding to the right lateral acceleration R received from the acceleration sensor 12 with the determination reference value Va1 for the right additional lighting lamp 4, and determines the left lateral acceleration L. The output signal Vb is compared with the determination reference value Vb1 for the left additional lighting lamp 5. Arithmetic control unit 13
Is the reference value Va for which the output signals Va and Vb received from the acceleration sensor 12 correspond to the respective lateral accelerations A1 and B1.
As long as it does not exceed 1, Vb1, each additional lighting fixture 4, 5 is not illuminated.

When the vehicle 1 turns right and the right lateral acceleration R increases, and the output signal Va from the acceleration sensor 12 exceeds the judgment reference value Va1 corresponding to the acceleration A1, during that time, the arithmetic control unit 13 moves to the right. A control signal is sent to the right additional lighting lamp driver unit 14 so as to light the additional lighting lamp 4. When the output signal Va becomes equal to or lower than the determination reference value Va1,
The arithmetic control unit 13 sends a control signal to the right additional lighting lamp driver unit 14 so as to turn off the right additional lighting lamp 4.

When the left lateral acceleration L changes due to the vehicle 1 turning left or the like, the arithmetic and control unit 13 lights up the judgment reference value Vb1 corresponding to the acceleration B1 as in the right lateral acceleration R. As the threshold value for the judgment criteria for turning off the light,
The left additional lighting lamp driver unit 1 is based on the comparison between the determination reference value Vb1 and the output signal Vb from the acceleration sensor 12.
A control signal for turning on / off the left additional lighting device 5 is sent to the control unit 5.

Therefore, in the light distribution control device 11 according to the present invention, the arithmetic control unit 13 senses the curving direction of the vehicle 11 and the curving direction by the output voltages Va and Vb from the acceleration sensor 12, and determines the curving direction. The turning on and off of any one of the additional lighting lamps 4 and 5 on the corresponding side is controlled. The control of the additional lighting lamps 4 and 5 does not use the steering angle of the tearing which is influenced by the uneven road surface. Therefore, there is no fear that the frequent blinking due to the uneven road surface as in the conventional case is repeated, and it is appropriate. Lighting and extinguishing control is performed.

In the example shown in FIG. 4, the lighting / turning-off start determination reference value Va1 for the right additional lighting lamp 4 and the lighting / turning-off start determination reference value Vb1 for the left additional lighting lamp 5 match each other. However, both Va1 and Vb1 can be set to different values.

In the embodiment of the present invention, the output voltages Va and Vb from the acceleration sensor 12 detect that the vehicle 1 is in a traveling state, and the start and stop of turning traveling and the turning direction of the vehicle 11 are determined. Is perceived. Therefore, according to this embodiment, the steering angle of the steering wheel and the signal from the vehicle speed sensor as in the related art are used by controlling the lighting and extinction of the additional lighting lamps 4 and 5 based on the lateral acceleration. Since it is possible to properly illuminate the turning direction of the vehicle 1 without being affected by the uneven road surface of the steering wheel, a vehicle speed signal from the vehicle speed sensor is required even for a vehicle having no steering sensor. Without doing so, the light distribution control device can be incorporated at low cost.

Further, the acceleration sensor 12 has an arithmetic control unit 13
Since the acceleration sensor 12 is incorporated in the vehicle 1, the acceleration sensor 12 is attached to the vehicle 1 by mounting the control circuit board 10 on which the arithmetic and control unit 13 is formed at a predetermined position without attaching the acceleration sensor 12 to the vehicle 1. Since the mounting work can be performed, the assembling work of the light distribution control device 11 to the vehicle 1 can be simplified. Regarding this assembly work,
As shown in FIG. 3, the control circuit board 10 in which the acceleration sensor 12 is incorporated can be assembled in advance to the one additional lighting lamp 4 or 5. As a result, the additional lighting lamp and the control circuit board 10 can be unitized, and the process of the assembling work can be simplified. By this uniting, the assembling work of the light distribution control device 11 can be further simplified. Can be planned.

Instead of the acceleration sensor 12, an angular velocity sensor having an output characteristic as shown in FIG. 6 can be used. As this angular velocity sensor, a known silicon type gyro sensor can be used. The horizontal axis of FIG. 6 represents the angular velocity ω, and the vertical axis represents the output voltage V from the angle sensor at that time. The analog voltage characteristic Q of the angular velocity sensor is
The linear characteristic is shown in the range from the maximum angular velocity detection value ω1 when the vehicle 1 turns right to the maximum angular velocity detection value ω2 when the vehicle 1 turns left.
In this linear characteristic region, the output voltage V of the angular velocity sensor is proportional to the angular velocity.

The arithmetic control unit 13 which receives the output voltage V from the angular velocity sensor as the detection signal K1 uses this output voltage V0 as a reference with respect to the output voltage V0 when the angular velocity detection value ω is zero.
When the output voltage V is lower than 0, it is determined to be a right turn,
When the output voltage V is higher than the output voltage V0, it is determined that the vehicle is making a left turn. Further, the calculation control unit 13 calculates the rotation angle from the straight ahead 1 of the vehicle 1 by time-integrating the output voltage V from the angular velocity sensor.

The calculation control unit 13 compares the rotation angle, which is a preset determination criterion, with the rotation angle obtained by the calculation process, and based on the comparison result, one additional lighting lamp 4 in the turning direction, The turning on and off of 5 is controlled.

In the above description, the additional lighting device has been described as an example of a fixed type additional lighting device in which the additional lighting device does not rock the irradiation region according to the turning angle of the vehicle. The present invention can be applied to a swing-type additional lighting lamp that swings. In the case of this swing-type additional lighting lamp, it is desirable to attach a circuit board incorporating an acceleration sensor or an angular velocity sensor to a fixed portion of the additional lighting lamp that serves as a support portion for the vehicle 1.

Further, each additional lighting lamp 4 according to the present invention,
For turning off the light of 5, it is possible to employ so-called dimming, in which the light amount is gradually reduced to turn off.

[0037]

According to the present invention, there is provided a light distribution control device for a vehicle headlamp, which is not limited to a vehicle type, can be manufactured at low cost, and can be minimized by the influence of road surface conditions such as unevenness. Provided.

[Brief description of drawings]

FIG. 1 is a front view schematically showing an arrangement example of an additional lighting lamp arranged in a front portion of a vehicle according to the present invention.

FIG. 2 is an explanatory diagram showing a light distribution pattern of a vehicle according to the present invention.

FIG. 3 is a vertical cross-sectional view schematically showing the inside of the additional lighting lamp according to the present invention.

FIG. 4 is a block circuit diagram of a light distribution control device according to the present invention.

FIG. 5 is a graph of output characteristics showing the relationship between lateral acceleration and output voltage received by the acceleration sensor according to the present invention.

FIG. 6 is a graph showing output voltage characteristics of the angular velocity sensor according to the present invention.

[Explanation of symbols]

1 vehicle A few headlamps Lighting equipment for additional lighting 11 Light distribution control device 12 Accelerometer 13 Arithmetic control unit (control circuit) 14, 15 Drive circuit section

Claims (4)

[Claims] 1. A light distribution control device for a vehicle headlamp, wherein additional lighting lamps for additionally illuminating the front of the vehicle in the traveling direction when traveling on a curve are provided on the front surface of the vehicle at intervals in the vehicle width direction. An acceleration sensor that detects the acceleration in the vehicle width direction accompanying the turning of the vehicle and outputs a detection signal; and an arithmetic control unit that controls lighting and extinction of the additional lighting lamp according to the output of the acceleration sensor. A light distribution control device for a vehicle headlight, comprising: the acceleration sensor incorporated in the arithmetic control unit. 2. The vehicle headlamp control system according to claim 1, wherein the arithmetic control unit is attached to the additional lighting lamp. 3. A light distribution control device for a vehicle headlamp, wherein additional lighting lamps for additionally illuminating the front of the vehicle in a traveling direction when traveling on a curve are provided at a front side of the vehicle with a space therebetween in the vehicle width direction. And an angular velocity detection sensor that detects an angular velocity associated with the turning of the vehicle and outputs a detection signal, and an arithmetic control unit that controls turning on and off of the additional lighting device according to the output of the angular velocity detection sensor. The light distribution control device for a vehicle headlamp, wherein the angular velocity detection sensor is incorporated in the arithmetic control unit. 4. The light distribution control device for a vehicle headlamp according to claim 3, wherein the arithmetic control unit is attached to the additional lighting lamp.