WO2009059990A1

WO2009059990A1 - Headlight for vehicles

Info

Publication number: WO2009059990A1
Application number: PCT/EP2008/064980
Authority: WO
Inventors: Mirco GÖTZ; Franz-Josef Kalze; Michael Kleinkes; Wolfgang Pohlmann; Thomas Vieregge
Original assignee: Hella Kgaa Hueck & Co.
Priority date: 2007-11-06
Filing date: 2008-11-05
Publication date: 2009-05-14
Also published as: DE102007052746A1; EP2210037B1; EP2210037A1

Abstract

The invention relates to a headlight for vehicles having a light module, which comprises a plurality of LED light sources and an optical unit, which is associated with the LED light sources, having a sensor apparatus for detecting an object located in a vehicle foreground, having a control unit which activates the light module as a function of a sensor signal provided by the sensor apparatus and/or a switching signal of a switching apparatus, to emit a predetermined light bundle, said light module having a first cell containing at least one LED light source such that, working together with the optical unit, a first wide light bundle is generated to generate a freeway light distribution, and the light module has at least one second cell containing at least one LED light source such that, working together with the same optical unit, at least one further wide light bundle can be generated, which directly adjoins the first wide light bundle immediately above it.

Description

Headlights for vehicles

The invention relates to a headlight for vehicles with a light module comprising a plurality of LED light sources and an optical unit associated with the LED light sources, with a sensor device for detecting an object located in the vehicle front, with a control device which is provided in response to one of the sensor device Sensor signal and / or a switching signal of a switching device, the light module drives to the radiation of a predetermined light beam.

From DE 10 2005 041 234 A1 discloses a headlamp for vehicles is known, which has at least two groups of LED light sources for generating a predetermined light distribution, which are summarized in a matrix-like manner on a substrate to an LED field. The LED fields are each preceded by an optical unit which has such an imaging characteristic that light bundles of different solid angles are radiated, which generate a predefined light distribution by superposition. The known headlight thus has a light module with a plurality of LED fields and optical units, so that the light module is relatively complex.

From DE 10 2004 042 092 A1 a headlamp for vehicles with a light module is known, which has a plurality of LED light sources, which are combined on a substrate to form an LED field. Furthermore, the headlight has a sensor device by means of which objects in the vehicle apron can be detected. The sensor device is interconnected with a control device which activates individual LED light sources of the LED field as a function of the sensor signal such that a light beam emitted by the light module has recessed areas where an oncoming traffic participant or preceding road user would be dazzled. The known headlamp thus enables the generation of a light distribution, which illuminates a large part of the vehicle apron with the exception of the recess area. Object of the present invention is to develop a headlamp for vehicles such that in a simple way improved illumination of the vehicle apron is ensured without glare occurs located in the vehicle apron road users.

To achieve this object, the invention in connection with the preamble of claim 1, characterized in that the light module comprises a first cell containing at least one LED light source, such that in cooperation with the optical unit, a first wide light beam for generating a motorway light distribution is generated and in that the light module has at least one second cell containing at least one LED light source such that, in cooperation with the same optical unit, at least one further wide light bundle can be generated, which adjoins directly above the first broad light bundle.

The particular advantage of the invention is that a light module is created in a simple manner, which illuminates an enlarged vehicle apron space in addition to a base light distribution generated by a further light module. Because a plurality of cells are provided, to which a common optical unit is assigned in such a way that at least two broad light beams can be generated, a light-dark boundary of the light distribution can be displaced variably in the vertical direction, depending on the current traffic situation. A first cell of the light module is used to generate a motorway light distribution, which is superimposed on a basic light distribution.

According to a preferred embodiment of the invention, the at least two cells of the light module and the optical unit are designed such that at least two wide light beams are emitted, each of which hit the vehicle apron at a horizontal critical angle of at least 8 ° and at a maximum vertical angle of 1 ° , Advantageously, this relatively wide light spots can be generated on a screen, so that by connecting the superimposed arranged wide light spots, the range of illumination can be increased. The fact that the vertical critical angle is limited to a maximum of 1 °, the light-dark boundary of the light distribution and the range of the light beam can be gradually increased or decreased.

According to a preferred embodiment of the invention, the optical unit is designed in such a way that the wide light beams emitted at different vertical angles are emitted with overlap of adjacent broad light beams. Advantageously, this results in a continuous transition when "switching on" or "switching off" of cells of the light module, while the bright-dark boundary has a relatively high luminance gradients.

According to a development of the invention, at least the first cell of the light module can be controlled in a dimmable manner so that relatively "soft" transitions are created between the lowermost wide light bundle and an upper edge of the basic light distribution or between the broad light bundles only at the cut-off line there is a relatively high luminance gradient.

According to a development of the invention, each cell of the light module has only a single LED chip. The upstream optical unit is designed such that a "widening" in the horizontal direction of the emitted light beam from the respective LED chip and thus a relatively wide light spots on the screen is generated.

According to an alternative embodiment, the cell may also be formed by a series of LED light sources, the number of rows of LED light sources corresponding to the number of wide light bundles. The optical unit in this case forms the individual LED light sources, so that pixel-like light sources are arranged in a plurality of horizontal rows on a measuring screen. Further advantages of the invention will become apparent from the further subclaims.

An embodiment of the invention will be explained in more detail with reference to the drawings.

Show it:

Fig. 1 is a block diagram of a headlamp and

Fig. 2 is a schematic representation of a light distribution of the headlamp on a screen.

A headlight for vehicles essentially consists of a housing 1, in which at least a first light module 2 and a second light module 3 are arranged.

The first light module 2 consists of three cells A, B, C of light sources, each cell A, B, C having a single LED chip 4. The LED chip 4 may have, for example, a single LED or, for example, four common potted LEDs.

The LED chips 4 of the cells A, B, C are arranged on a common substrate 5. The cells A, B, C are preceded by a common optical unit 6, which in each case scatters the light generated by the cells A, B, C into narrow, horizontally extending light bundles a, b and c. In the present embodiment, the light generated by the o- bere cell A is scattered into a first wide light beam a to form a lower wide light spot 7, which impinges on a measuring screen 18 at an angle of -0.28 ° below the horizontal H. The light generated by the middle cell B is scattered by means of the optical unit 6 such that a second broad light beam b is generated to form a middle wide light spot 8, which is arranged on the measuring screen 18 at least partially overlapping above the first broad light beam a. A generated by the lower cell C light is using the optical unit 6 is scattered such that another wide light beam c is imaged to form an upper wide light spot 9 on the screen.

The second light module 3 has, as a light source, an LED chip 11 to which a second optical unit 10 is assigned to form a basic light distribution 12. The LED chip

11 and the second optical unit 10 is formed such that as a basic light distribution

12 a low-beam light distribution is formed with a light-dark boundary HDG having a 15 ° rise 13.

For improved illumination of the vehicle apron, the cells A, B, C can be switched on or off in succession. For this purpose, the cells A, B, C are controlled by means of a control device 14 which is coupled on the input side to a sensor device 15 and to a switching device 16 on the input side. The sensor device 15, which is preferably arranged outside the housing 1, is designed such that objects located in the vehicle apron can be detected. For example, preceding or oncoming traffic participants can be detected and located. The switching device 16 may be arranged, for example, in the cockpit of the vehicle, so that manually or in dependence on predetermined parameters, an input, shutdown of cells A, B, C is made possible.

In the present exemplary embodiment, the narrow light bundles a, b, c have a horizontal critical angle α of at least 8 ° and a vertical critical angle β of at most 1 °. Horizontal limiting angle α is understood to be the opening angle of the corresponding light bundle in the horizontal direction and the vertical limit angle β the opening angle of the corresponding light bundle in the vertical direction.

In the present embodiment, the horizontal critical angle α of the light bundles a, b, c is 10 °, the formed wide light spots 7, 8, 9 are arranged symmetrically to a vertical V. The vertical limit angle β of the light bundles a, b, c is about 0.3 °, so that the lower light bundle a for generating a motorway light Distribution serves. The lower light spot 7 generated by the lower light bundle a extends under overlap to a horizontal light-dark boundary HDG of the low-beam light distribution 12. The motorway light can be achieved, for example, by dimming the cell A in a dimmed manner, so that a homogenous expansion of the driving can be carried out. Depending on the location of objects in the vehicle apron then the other cells B and C can be switched on or off. This connection or disconnection can also be made dimmable. By the electrically switchable activation of the cells A, B, C, a "cross-fading" of an upper edge region 17 of the basic light distribution can take place which adaptively adapts the bright-dark boundary HDG of the resulting light distribution to the current traffic situation.

Preferably, the LED chips 11 of the cells A, B, C and the optical unit 6 are formed such that upon activation of the cells A, B, C, an overlap of adjacent wide light spots 7, 8, 9 occurs. As can be seen from FIG. 2, the wide light spots 7, 8, 9 have the same contour, so that the broad light bundles a, b, c have the same horizontal critical angle α and vertical critical angle β.

According to an alternative embodiment of the cells A, B, C, these can each also be formed by a series of LED chips 4, wherein the optical unit 6 images the light emitted by the respective rows of LED chips 4 to pixel-like light spots, which in one horizontal row are arranged. This row of light spots corresponds in each case to the wide light spots 7, 8, 9 when the cells A, B, C are executed with the respective single LED chips 4. LIST OF REFERENCE NUMBERS

1 housing

2 first light module

3 second light module

4 LED chip

5 substrate

6 optical unit

7 lower wide light spot

8 medium wide light spot

9 upper wide light spot

10 second optical unit

11 LED chip

12 basic light distribution

13 15 ° rise

14 control device

15 sensor device

16 switching device

17 border area

18 screen

A ₁ B ₁ C cells a, b, c light bundle

H horizontal

HDG light-dark border

V Vertical α horizontal limit angle ß vertical limit angle

Claims

Headlights for vehiclesPatent claims

1. A headlamp for vehicles with a light module containing a plurality of LED light sources and an LED unit associated with the optical light sources, with a sensor device for detecting an object located in the vehicle front, with a control device in response to a provided by the sensor device sensor signal and The light module (2) has a first cell (A) containing at least one LED light source (4) in such a way that, in cooperation with the optical unit (2), the light module activates the radiation of a predetermined light beam. 6), a first broad light beam (a) for generating a highway light distribution (7) is generated, and that the light module (2) at least one second cell (B, C) comprising at least one LED light source (4), such that in Cooperation with the same optical unit (6) at least one further wide light beam (b, c) can be generated, which adjoins directly above the first broad light beam (a).

2. Headlight according to claim 1, characterized in that the first cell (A) and the other cells (B, C) is formed either by a single LED chip (4) or a series of LED chips and that the optical unit ( 6) has an imaging characteristic such that the first broad light bundle (a) and the further wide light bundles (b, c) are radiated at a horizontal critical angle (α) of at least 8 ° and at a vertical critical angle (β) of at most 1 ° ,

3. Headlight according to claim 1 or 2, characterized in that at least the first cell (A) of the light module (2) is dimmably controlled.

4. Headlight according to one of claims 1 to 3, characterized in that the optical unit (6) is formed such that the first wide light beam (a) and the other wide light bundles (b, c) have the same horizontal and / or vertical critical angle ( α, ß).

5. Headlight according to one of claims 1 to 4, characterized in that the optical unit (6) is designed such that the wide light bundles (a, b, c) on a measuring screen (18) to form an overlap of adjacent light bundles (a , b, c) are arranged one above the other.

6. Headlight according to one of claims 1 to 5, characterized in that the optical unit (6) is formed such that the first wide light beam (a) at a vertical angle of -0.28 ° to the horizontal (H) on the Measuring screen (18) is arranged.

7. Headlight according to one of claims 1 to 6, characterized in that a second light module (3) containing an LED light source (11) and an optical unit (10) is provided for generating a basic light distribution (12).

8. Headlight according to one of claims 1 to 9, characterized in that the light spots formed by the first broad light beam (a) (7) Ü is disposed overlapping to an upper edge (17) of the basic light distribution (12).

9. Headlight according to one of claims 1 to 8, characterized in that the cells (A, B, C) of the first light module (2) are arranged side by side in the vertical direction.

10. Headlight according to one of claims 1 to 9, characterized in that the cells (A, B, C) of the first light module (2) by means of the control device (14) are driven such that the cut-off line (HDG) the basic light distribution (12) is changed in the vertical direction as a function of the traffic situation determined by means of the sensor device (15).