DE102012004823A1 - Diaphragm for headlight i.e. projection headlight, of motor car, has semi-transparent structures formed in region of outer edge of diaphragm and designed such that gradient of bright-dark borders comprises steady course - Google Patents

Abstract

The diaphragm (3) has an outer contour that is adapted to receive a light beam to generate bright-dark borders. Semi-transparent structures are formed in a region of an outer edge of the diaphragm. The semi-transparent structures are designed such that a gradient of the bright-dark borders comprises a steady course. The semi-transparent structures are formed as adjacent recesses (7) that form a comb-like structure. The semi-transparent structures are formed by an opaque coating on a glass or plastic substrate. The semi-transparent structure comprises apertures and protruding elements. An independent claim is also included for a headlight for a motor car.

Description

The invention relates to a diaphragm in a vehicle headlight.

In the more recent development of driving lights, the focus is increasingly on optimizing driving safety. In addition to other improvements in lighting technology, such as the use of LEDs or xenon lamps, assistance systems have meanwhile also found their way into modern motor vehicles. Known assistance systems are, for example, a curve light assistance system for changing the illumination emission during cornering or an aid known under the term AFL system (AFL = adaptive forward lighting, adaptive front lighting), which can carry out a headlight range adjustment depending on the driving situation.

From the general state of the art known vehicle headlights are usually divided in terms of their structure in projection headlights and reflection headlights. Known projection headlights have a diaphragm, which ensures a suitable limitation of the light emission in the case of operation in the low-beam mode.

An example of an aperture for a low beam headlight of motor vehicles is from the DE 4317961 A1 known. In this aperture, seen in the beam direction having a first portion with a horizontal boundary edge and extending to the optical axis and at which a second section for generating an asymmetrical light beam on the side facing the roadway edge and which is inclined downwards, closes to the second section to a third section, whose boundary edge rises again. Furthermore, this publication shows a diaphragm for a low beam headlamp with a rounded diaphragm edge for influencing the gradient at the cut-off line.

In general, a sharp cut-off line is distracting. The cut-off line can also be influenced only to a limited extent by means of further optical elements, such as lenses. In addition, in a vehicle headlamp with a headlamp leveling, if necessary, a differently pronounced cut-off point can be observed depending on the light distribution, which is also perceived as disturbing.

An object of the invention is to provide a diaphragm for a vehicle headlight, in which the course of the cut-off line is further improved.

This object is solved by the features of patent claim 1. Further advantageous embodiments of the invention are each the subject of the dependent claims. These can be combined in a technologically meaningful way. The description, in particular in conjunction with the drawing, additionally characterizes and specifies the invention.

According to the invention, a diaphragm for a vehicle headlight is provided which has an outer contour which is suitable for producing a light cone with a light-dark boundary, wherein the diaphragm has, in the region of an outer edge, a semi-transparent structuring which is designed such that the light-dark border has a smooth course.

Through a structured aperture, a softer and, moreover, dynamically controllable cut-off can be achieved. In this case, light which is absorbed in standard systems by a continuous edge profile of the diaphragm, partially to the light exit surface, z. B. a lens, and affect the gradient of the cut-off. In the context of, for example, a legislator prescribed glare value maxima, the cut-off threshold can now also be adapted dynamically to the respective driving situation or to the AFL mode.

In another embodiment, the semi-transparent patterning is implemented as a plurality of adjacent recesses forming a comb-like structure.

In this way, light partially passes out of the previously absorbed region via a lens out of the headlight and now contributes specifically to the light characteristic on the road. The shape or the number of juxtaposed recesses can be selected so that the desired light characteristic is established on the road.

In a further embodiment, the semi-transparent structuring is carried out by means of a plurality of openings in the diaphragm.

According to this embodiment, a further possibility for influencing the light characteristic is created. The size or the number of openings can be selected so that the desired light characteristic is established on the road.

The semi-transparent structuring can also be formed by means of a plurality of projecting elements.

Accordingly, an alternative embodiment is provided which can be used to influence the light characteristic.

In a further embodiment, the opaque coating is formed on a glass or plastic substrate in a printing process, preferably in a through-printing process, in particular in a screen printing process.

The use of glass or plastic substrates as a panel can also result in less noise when switching between dipped and main beam.

Furthermore, a headlight of a motor vehicle with an aperture described above is specified.

The diaphragm is arranged within a projection module of the headlight for a specific adjustment of the sharpness profile of the cut-off line. Here, the aperture, which forms the light limit for the low beam, provided with a partially transparent structuring.

This panel is constructed in the prior art with a continuous top edge. This continuous upper edge forcibly creates a very sharp cut-off, which can be defused only by defocusing the aperture in the overall system, or a corresponding lens design.

Both options for defusing the cut-off line are static adjustments, which are set once for all light modes and are invariable afterwards. Even a local sharpness adjustment of the cut-off line is not possible. In order to tailor the cut-off line for different operating modes in an AFL system or driving situations, the continuous outer edge of the diaphragm is widened as described above. By this measure, light partially passes out of the previously absorbed area via a lens out of the headlight and now contributes specifically to the light characteristic on the road.

The headlight can be connected to an assistance system. As an assistance system, for example, a cornering light system or an AFL system can be used.

The cut-off line can be adapted in a targeted manner and, depending on the light mode (eg: city trip soft, highway trip hard) have a different course. The headlight range adjustment can be done by adjusting the aperture, so that no flexible suspension of a static panel is necessary, which can lead to a cost reduction.

In the front headlamp, the aperture may be connectable to a rotating mechanism to allow dynamic adjustment of the gradient of the cut-off line.

The headlamp may have another aperture to allow dynamic adjustment of the gradient of the cut-off line together with the aperture.

Some embodiments will be explained in more detail with reference to the drawing. Show it:

1 : a headlight according to the invention in a sectional view,

2a FIG. 1 schematically shows a light cone according to a comparative example, FIG.

2 B FIG. 2 schematically shows a light cone according to the invention, FIG.

3 FIG. 2 shows a view from above of a panel according to a first embodiment, FIG.

4 FIG. 2: a view of a diaphragm according to the invention in a plan view according to a second embodiment, FIG.

5 FIG. 2: a view of a diaphragm according to the invention in a plan view according to a third embodiment, FIG.

6 FIG. 2: a view of a diaphragm according to the invention in a plan view according to a fourth embodiment, FIG.

7 FIG. 2 shows a view from above of a diaphragm according to a fifth embodiment, and FIG

8th FIG. 2: a view of a diaphragm according to the invention in a plan view according to a sixth embodiment. FIG.

In the figures, identical or functionally identical components are provided with the same reference numerals.

In 1 is a front view in a cross-sectional view 1 shown, which is designed as a projection headlight. These are a suitably shaped reflector 2 and a lens 4 intended. Between the reflector 2 and the lens 4 is a blind 3 Arranged by a light source 5 radiated light 6 affected. By introducing the aperture 3 can therefore the radiated light 6 be brought from a high beam operation in a low beam operation.

In conventional headlamps, as known from the prior art, a road illumination is achieved in low beam operation, as in 2a is shown. That of the headlight 1 emitted light forms a cone of light 10 which has a sharp cut-off line at the edge.

According to the invention, the cut-off line becomes softer, that is to say the light distribution at the transition between the light cone 10 and the area outside the cone of light has a gradient with a steady course. This is in 2 B based on the hatched area 11 shown.

To achieve the soft cut-off, the aperture becomes 3 provided with a partially transparent structure, so that the emitted light 6 partially from the previously absorbed area over the lens 4 from the headlight 1 can step out. The part of radiated light passing through the partially transparent structure 6 now contributes specifically to the light characteristics on the road.

The outer contour of the panel 3 follows the course known from the prior art. In the area of the upper outer edge of the panel 3 However, a semi-transparent structuring is provided. The partially transparent structure on the panel can be achieved in several ways, as explained below.

In 3 In a first embodiment, the semi-transparent patterning is shown as a plurality of adjacent recesses 7 is executed, which form a comb-like structure. The shape or the number of adjacent recesses 7 can be chosen so that by means of the aperture 3 in the 2 B shown bright-dark border 11 on the street.

As in 4 is shown, the semi-transparent structuring can also by means of a plurality of openings 8th in the aperture 3 be executed, the size or position, in turn, the light characteristics of the headlamp 1 determine.

Another embodiment is in 5 shown. In this example, the aperture 3 is the semi-transparent structuring by means of a plurality of projecting elements 9 formed in the area of the outer edge of the panel 3 are arranged.

The headlight 1 can also with another aperture 12 be equipped with the aperture 3 allows a dynamic adjustment of the gradient of the cut-off line by the further aperture 12 over the aperture 3 is displaceable, as in 6 is shown. Moving the other aperture 12 over the aperture 3 This can be done by means of an assistance system, so that an adaptation of the gradient of the cut-off line is achieved as a function of the driving speed. Thus, for example, a highway driving a hard course and during a city driving a smooth course of the cut-off line can be achieved.

Another option for dynamic adaptation is in 7 shown. The aperture 3 is with a rotation axis 14 connected over which the aperture 3 can be tilted. As a result, the cut-off point can also be adjusted. In addition, both options for headlamp leveling can be used.

The semi-transparent structuring can also be achieved by means of an opaque coating 13 be achieved, which the recesses 7 has corresponding openings to let light pass specifically. The opaque coating 13 can in a printing process z. B. be formed in a screen printing on a glass or plastic substrate.

Although some possible embodiments of the invention have been disclosed in the foregoing description, it is to be understood that numerous other variants of embodiments exist through the possibility of combining all of the cited and further all of the obvious technical features and embodiments. It is further understood that the embodiments are to be understood as examples only, which in no way limit the scope, applicability and configuration. Rather, the foregoing description would suggest a suitable way for the skilled person to realize at least one exemplary embodiment. It should be understood that in an exemplary embodiment, numerous changes in the function and arrangement of the elements may be made without departing from the scope and equivalents disclosed in the claims.

LIST OF REFERENCE NUMBERS

1

headlamp

2

reflector

3

cover

4

lens

5

Lamp

6

radiated light

7

recess

8th

opening

9

projecting element

10

light cone

11

Light-off

12

further aperture

13

coating

14

axis of rotation

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 4317961 A1 [0004]

Claims (10)

Cover for a vehicle headlight ( 1 ), which has an outer contour suitable for illuminating a cone of light ( 10 ) with a light-dark boundary, whereby the diaphragm ( 3 ) in the region of an outer edge a partially transparent structuring ( 7 ; 8th ; 9 ), which is designed such that a gradient of the cut-off line ( 11 ) has a steady course. An orifice as claimed in claim 1, in which the semi-transparent structuring is designed as a plurality of adjacent recesses ( 7 ) is formed, which form a comb-like structure. Aperture according to Claim 1, in which the semi-transparent structuring is effected by means of a multiplicity of openings ( 8th ) is executed in the aperture. Aperture according to Claim 1, in which the semitransparent structuring is effected by means of a multiplicity of projecting elements ( 9 ) is formed. Aperture according to Claim 1, in which the semi-transparent structuring by means of an opaque coating ( 13 ) is formed on a glass or plastic substrate. Aperture according to Claim 5, in which the opaque coating ( 13 ) is formed in a printing process, preferably in a through-printing process, in particular in a screen printing process. Headlight of a motor vehicle with a diaphragm ( 3 ) according to one of claims 1 to 6. Headlamp according to claim 7, which is connectable to an assistance system, in particular a cornering light system or an AFL system. Front headlamp according to one of claims 7 or 8, in which the diaphragm ( 3 ) with a rotating mechanism ( 14 ) in order to dynamically adjust the gradient of the cut-off line ( 11 ). Front headlamp according to one of claims 7 or 8, which has a further diaphragm ( 12 ), which together with the diaphragm ( 3 ) a dynamic adjustment of the gradient of the cut-off line ( 11 ) by the further aperture ( 12 ) over the aperture ( 3 ) is displaceable.

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