JP2002127813A - Vehicular headlight - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a means of preventing or reducing dazzlement caused by an oncoming traffic, even when a failure such as the malfunction of an adjusting device occurs. SOLUTION: A safety device is provided, and the function of the adjusting device is at least indirectly monitored by the safety device. When the adjusting device does not properly function in case of a trouble, an electric output to actuate a light source is reduced by the safety device, and/or the illumination distance of light flux generated by a headlight unit is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a headlight for a vehicle, wherein at least one headlight unit is provided, and the headlight unit generates a dimmed light beam, and the light beam is emitted. Has an asymmetric upper light-dark boundary, the luminous flux has a greater illumination distance in the traveling lane of the own vehicle than in the traveling lane of the oncoming vehicle, and the headlight unit is located in front of the vehicle. Depending on the trajectory of the roadway, it can be pivoted by an adjusting device to change the trajectory of the light beam in a horizontal direction, and the headlight unit can be centered at least approximately horizontally by an illuminating distance adjusting device. As a type that can be turned.

[0002]

2. Description of the Related Art A headlight of this type is known from DE 198 60 461 A1. The headlight has a headlight unit, which produces a dimmed light beam with an asymmetric upper light-dark boundary. As a result, the luminous flux shows a larger illumination distance in the traveling lane of the own vehicle than in the traveling lane of the oncoming vehicle. The headlight unit can be turned by an adjusting device to change the trajectory of the light beam in a horizontal direction, depending on the trajectory of the roadway ahead of the vehicle. Thus, when traveling on a curve, sufficient illumination of the road ahead of the vehicle according to the actual track of the road is obtained. The headlight unit is further pivotable about an axis extending at least substantially horizontally by means of an illumination distance adjusting device. In the event of a malfunction of the adjusting device, it is possible that the headlight unit remains in a certain position and that the luminous flux has a large lighting distance in the driving lane of the oncoming vehicle so as to cause dazzling counter traffic. And this must be prevented. For example, this is the case where the headlight unit is at a position for traveling on a left curve while the vehicle is traveling on a right curve while traveling on the right.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a means for preventing or reducing dazzling of opposing traffic even when a malfunction such as a malfunction of the adjusting device occurs. is there.

[0004]

In order to solve this problem, according to the present invention, a safety device is provided, by which the function of the adjusting device is monitored at least indirectly, and in the event of a fault. The safety device may reduce the electrical power at which the light source is activated and / or reduce the illuminating distance of the luminous flux generated by the headlight unit if the adjusting device is not functioning properly. Has become.

[0005]

The headlight having the configuration according to the first aspect of the present invention has the following advantages over the conventional headlight. That is, the safety device can recognize an erroneous function of the adjusting device, and can prevent dazzling of opposing traffic. This can be done by reducing the power at which the light source is activated and / or by reducing the illumination distance of the luminous flux produced by the headlight unit.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings.

The headlight for a vehicle, in particular for a motor vehicle, shown in FIGS. 1 and 2, has at least one headlight unit 10, which has a reduced luminous flux, for example, It is used to generate at least a passing beam bundle. The headlight unit 10 has a reflector 12 and a light source 14, which is an incandescent lamp or preferably a gas discharge lamp. The reflector 12 together with the light source 14 form a headlight unit 10, which is adjustably arranged in a holder or casing 15. The light exit opening of the casing 15 is covered by a light transmitting plate 16 made of glass or plastic. The light transmitting plate 16 may be formed as a smooth plate, or may have an optical molded body at least locally. The passing light is deflected and / or scattered by the optical molding. The reflector 12
The reflector 12 has an opening for the light source 14 in the top region of the reflector 12. The headlight unit 10 may be configured according to the projection principle, and may have, in addition to the reflector 12 and the light source 14, a shade 17 arranged on the optical path of the light reflected by the reflector 12. Good. The shade 17 creates a light-dark boundary of a light beam emitted from the headlight unit 10. Further, the headlight unit 10 may have a lens 18,
Light that is reflected by the reflector 12 and passes by the shade 17 passes through the lens 18.

[0008] The headlight unit 10 produces a low beam bundle having an asymmetric upper and lower boundary. As a result, the passing beam bundle is generated in the traveling lane of the own vehicle, that is, in the traveling lane on the right side of the right-hand traffic,
Indicates an illumination distance greater than the traveling lane of the oncoming vehicle. FIG.
FIG. 1 shows a measuring screen 80 spaced in front of the headlights, which is illuminated by a low beam bundle generated by the headlight unit 10. The measurement screen 80 has a horizontal center plane HH and a vertical center plane VV, and both center planes cross each other at a point HV. The measuring screen 80 represents a projected image of the roadway to be illuminated by the headlight unit 10 accordingly. Since the headlight unit 10 is set for right-hand traffic, the traveling lane of the own vehicle is on the right side of the measurement screen 80, and the traveling lane of the oncoming vehicle is on the left side of the measurement screen 80. The area 82 of the measuring screen 80 is illuminated by the low beam produced by the headlight unit 10. Region 82 is bounded above by a light-dark boundary. The light-dark boundary has a horizontal section 83 on the traveling lane of the oncoming vehicle, that is, on the left side of the measurement screen 80, and starts from the horizontal section 83 on the traveling lane of the own vehicle, that is, on the right side of the measurement screen 80. And has a section 84 which rises to the right. The horizontal section 83 of the light-dark boundary extends approximately 1%, that is, approximately 0.57 ° below the horizontal center plane HH of the measurement screen 80. The section 84 of the light-dark boundary rises at an angle of approximately 15 ° with respect to the horizontal center plane HH. Area 8
The distribution of the illuminance of No. 2 is specified by a plurality of lines 85 indicating the same illuminance, so-called iso-illuminance curves.

The headlight unit 10 includes the adjusting device 3
By means of 0, it is possible to turn to change the trajectory of the light beam generated by the headlight unit 10 horizontally, depending on the trajectory of the roadway ahead of the vehicle. In this case, the headlight unit 10 is pivotable about an axis 32 that extends at least substantially vertically. The adjusting device 30 has an electric drive 34 in the form of, for example, an electric motor, an electromagnet or a piezo actuator. When the vehicle goes straight ahead, the headlight unit 10
Is not turned around the headlight unit 10
The optical axis 11 extends substantially parallel to the longitudinal axis of the vehicle. In this non-rotated position, the passing beam bundle generated by the headlight unit 10 causes the area 8 of the measuring screen 80 shown in FIG.
2 is illuminated. If the vehicle runs on the right curve,
The headlight unit 10 is controlled by the adjusting device 30
As shown in FIG. 2, it is turned around the axis 32 clockwise as viewed from above. Correspondingly, the area illuminated by the passing beam bundle is shifted to the right to the position indicated by the numeral 82a, indicated by the dashed line in FIG. Bright and dark boundaries of the area 82a are represented by reference numerals 83a and 84a. When the vehicle travels on the left curve, the headlight unit 10 is turned around the shaft 32 counterclockwise as viewed from above by the adjusting device 30 as shown in FIG. Correspondingly, the area illuminated by the passing beam bundle is indicated by the dash-dot line in FIG.
It is shifted left to the position represented by 2b. Bright and dark boundaries of the area 82b are represented by reference numerals 83b and 84b. This turning around the axis 32 of the headlight unit 10 provides illumination according to the actual trajectory of the roadway.
When the headlight unit 10 is in the position where the headlight unit 10 is turned counterclockwise and the area 82b is illuminated by the passing beam bundle, however, when the vehicle goes straight or runs on a right curve, the light-dark boundary rises. Category 8
4 exists in the traveling lane of the oncoming vehicle, and the illumination distance of the passing beam bundle is large, so that dazzling of oncoming traffic occurs.

The headlight has an illumination distance adjustment device 40 in addition to the adjustment device 30. The illumination distance adjustment device 40 can change the illumination distance of the light beam generated by the headlight unit 10. it can. The illumination distance adjusting device 40 allows the headlight unit 10 to pivot about an axis 42 that extends at least substantially horizontally. This illumination distance adjusting device 40
May have an electric drive motor 44, via which an adjusting element 45 pivotally connected to the reflector 12 is movable, and The turning of the headlight unit 10 about the axis 42 is obtained by the element 45. The headlight is fixed to the body or the superstructure of the vehicle in a manner not shown. The inclination of the body or superstructure of the vehicle may change when the loading condition of the vehicle changes or during traveling, in which case the tilt of the headlights is also changed, and thus the illumination of the luminous flux produced by the headlights. The distance can also be changed.
Especially for the passing beam bundle, the illumination distance and thus the vertical position of the light-dark boundaries 83, 84 are precisely defined in order to prevent dazzling counter traffic. The illuminating distance adjusting device 40 is adapted to rotate the headlight unit 10 around the axis
Is used to keep the illumination distance of the passing beam bundle generated by the vehicle at least approximately constant, independent of the vehicle loading. When no car is loaded, the illumination distance and thus the positions of the light and dark boundaries 83 and 84 are properly adjusted. If a car is loaded,
The headlight unit 1 is controlled by the illumination distance adjusting device 40.
0 is pivoted down about axis 42 so that the illumination distance and thus the position of light / dark boundaries 83, 84 are still properly adjusted.

For the light source 14, an electrical stabilizer 46 is provided.
The electric ballast 46 causes the light source 14 to be activated depending on the operating state of the light source 14, including the required voltage, current and electrical output determined by both values. This stabilizer 46 serves for ignition of the light source 14 and for enabling a stable operation of the light source 14.

According to the present invention, the safety device 50 is provided on the headlight, and the safety device 50 allows the adjustment device 30 to function properly and to ensure that the headlight unit 10 is in an appropriate position, that is, in a straight running state. It is monitored whether the vehicle is in a position where the vehicle is not turned, a position where the vehicle is turned counterclockwise when traveling on a right curve, and a position where the vehicle is rotated clockwise when traveling a left curve. Safety device 5
By means of 0, for example, the operating current of the drive 34 of the adjusting device 30 is monitored. When the adjusting device 30 is activated, in order to rotate the headlight unit 10,
The current is supplied at the current value set in the driving unit 34. If the actual current value deviates from the set current value,
From this, it can be inferred that the malfunction of the adjusting device 30 can be inferred, and that the headlight unit 10 is not in a position appropriate for the current trajectory of the roadway ahead of the vehicle. If the electrical connection between the regulating device 30 and the required voltage source is interrupted, for example by a cable break, there is no operating current for the drive 34, which is recognized by the safety device 50 as a fault. Is done. If the elements of the headlight unit 10 or the adjusting device 30 are locked, an operating current for the drive 34 that is higher than the set operating current is generated, which is likewise achieved by the safety device 50. Recognized as a failure. From this, it can be seen that also in this case, the headlight unit 10 is not at an appropriate position.

When a malfunction is recognized by the safety device 50, measures are taken to prevent or at least reduce the dazzling of opposing traffic. The safety device 50 is a stabilizer 4 for the light source 14.
6 can also be influenced as follows: the light source 14 is operated by the ballast 46 at an electrical output smaller than the normal electrical output. The electrical output is reduced in this case to the point where no dazzling or only little dazzling counter traffic is caused. The electrical output is
In this case, the light source 14 can be reduced to zero, so that the operation of the light source 14 is stopped and shut off. Usually, two headlights are provided on a car,
If a gas discharge lamp is used as the light source 14, sufficient illumination is guaranteed if only one headlight is activated.

As an alternative or in addition to the aforementioned reduction in the electrical output at which the light source 14 is activated, the safety device 50 also causes the lighting distance adjustment device 40 in the event of a fault to: The headlight unit 10 can be controlled so as to be pivoted downward about the axis 42 and, consequently, the illumination distance of the light beam generated by the headlight is reduced. Accordingly, when the headlight unit 10 is in the position where the headlight unit 10 is turned counterclockwise and the passing beam bundle illuminates the area 82b, the passing beam bundle is lowered in the area 82b in FIG. It can be lowered until it reaches the position 82c indicated by the dashed line. Light and dark boundaries of the area 82c are indicated by reference numerals 83c and 84c. This area 82c is lowered to a position where it does not protrude beyond the horizontal center plane HH of the measuring screen 80 at least in the traveling lane of the oncoming vehicle. By lowering the passing beam bundle, the illumination distance adjusting device 40
Is used, dazzling of the opposing traffic is prevented or at least reduced. Additionally, as mentioned above,
The electrical power at which the light source 14 is activated can also be reduced.

The position of the headlight unit 10 can be monitored by the safety device 50 to determine whether the headlight unit 10 corresponds to the set proper position. In this case, the safety device 50 monitors whether the headlight unit 10 is at the appropriate position set for the respective trajectory of the roadway, ie, straight ahead, right curve or left curve. In this case, position sensors 52 are provided for various positions taken by the headlight unit 10, and the position sensors 5
2, the position of the headlight unit 10 at each position is detected. As the position sensor 52, for example, a potentiometer, a limit switch, or a position feedback sensor can be used. With the position sensor 52, the headlight unit 1
If the proper position of 0 is not detected, this is recognized by the safety device 50, and the output of the light source 14 is reduced or the light source 14
And / or illumination distance adjusting device 4 for headlight unit 10
A downturn by zero occurs. Position sensor 52
Accordingly, it is only necessary to detect whether or not the headlight unit 10 is at an appropriate position during straight running. If the headlight unit 10 is not at the appropriate position, it is determined that a malfunction has occurred.

As an alternative or in addition to the above arrangement,
The illuminating distance of the luminous flux generated by the headlight unit 10 may also be reduced in the event of a fault, by the safety device 50 activating the shielding device 54. The shield device 54 at least partially shields a part of the light beam generated by the headlight unit 10 and having an extremely large illumination distance. The shield device 54 may be formed as a movable shade or may be formed in a fixed position so that the light transmittance is variable. The shield device 54, which is formed as a movable shade, is, for example, the shade 1 of the headlight unit 10 when not in operation.
Located below the upper edge of 7 and can be moved to protrude beyond the upper edge of shade 17 when activated. Thus, the light reflected by the reflector 12 is shielded by the shield device 54. The shield device 54 may be arranged on the optical path between the light source 14 and the reflector 12 or on the optical path of the light beam reflected by the reflector 12. The movement of the shield device 54 can be performed by an electric drive 56 such as an electric motor or an electromagnet.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of a headlight unit in a vertical direction.

FIG. 2 is a horizontal longitudinal sectional view of the headlight unit.

FIG. 3 is a view of a measuring screen arranged in front of the headlight unit, illuminated by a light beam generated by the headlight unit.

[Explanation of symbols]

10 headlight unit, 11 optical axis,
12 reflector, 14 light source, 15 casing,
16 light transmission plate, 17 shade, 18 lens, 30 adjustment device, 32 axis, 34 drive unit,
Reference Signs List 40 illumination distance adjustment device, 44 electric drive motor, 45 adjustment device, 46 stabilizer, 50 safety device, 52 position sensor, 54 shield device, 56 drive unit, 80 measurement screen, 82
Area, 83 horizontal section, 84 section rising to the right, 85 lines

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F21V 7/16 B60Q 1/04 E 14/02 F21M 3/20 Z 14/04 3/22 K 14/08 // F21W 101: 10 F21Y 101: 00 (72) Inventor Michael Ham Germany Pfringen wer Tostrasse 137/4 (72) Inventor Doris Bebel Germany Stuttgart im Unteren Keenle 13 F-term (reference) 3K039 AA04 CC01 FD11 GA02 HA01 HA03 JA03 3K042 AA08 AC06 AC07 BB01 BC01 BD04 BE09 CB13 CB20

Claims (6)

[Claims] 1. A headlight for a vehicle, comprising at least one headlight unit (10), wherein a reduced light beam is generated by the headlight unit (10), and the light beam is emitted by the headlight unit (10). The headlight unit has an asymmetric upper light / dark boundary (83, 84), and the luminous flux has a larger illumination distance in the traveling lane of the own vehicle than in the traveling lane of the oncoming vehicle. (1
0) can be turned by an adjusting device (30) to change the trajectory of the light beam in the horizontal direction, depending on the trajectory of the roadway ahead of the vehicle, and the headlight unit (10) is illuminated By the distance adjusting device (40)
A safety device (50) is provided, at least of the type pivotable about an axis (42) extending at least substantially horizontally, wherein the safety device (5) is provided.
0) at least indirectly monitors the function of the adjusting device, and in the event of a malfunction, if the adjusting device (30) is not functioning properly, the light source (14) is activated by the safety device (50). Electrical output is reduced, and / or
Alternatively, an illumination distance of a light beam generated by the headlight unit is reduced. 2. The regulating device (30) has an electric drive (34), the operating current of which is reduced from the operating current set by the safety device (50). The headlight according to claim 1, wherein the headlight is monitored for deviation. 3. The headlight according to claim 1, wherein the position of the headlight unit (10) is monitored at least indirectly by a safety device (50) for a set position. 4. In the event of a fault, a safety device (50)
4. The headlight according to claim 1, wherein the operation of the light source (14) is stopped. 5. An illumination distance adjusting device (40) in the event of a failure.
4. The headlight according to claim 1, wherein the headlight unit (10) is controlled by a safety device (50) to be pivoted downward by the illumination distance adjusting device (40). . 6. In the event of a fault, the safety device (50)
The shield device (54) is activated, and the shield device (5) is activated.
4) By means of 4), a part of the light beam having a very large illumination distance created by the headlight unit (10) is at least partially blocked.
The headlight according to any one of the above.