Lighting device for a motor vehicle headlight

Patent metadata

Field	Value
Publication number	US-10876696-B2
Application number	US-201816470679-A
Country	US
Kind code	B2
Filing date	Jan 8, 2018
Priority date	Jan 20, 2017
Publication date	Dec 29, 2020
Grant date	Dec 29, 2020

Abstract

The invention relates to a lighting device ( 1 ) for a motor vehicle headlight, comprising a plurality of light sources, a light guide unit ( 3 ) that is made of a light-conducting solid body and comprises a plurality of light guides ( 3 b ), and a downstream projection lens ( 4 ) including a focal plane (E), each light guide ( 3 b ) comprising a light incoupling surface ( 3 b ′) for coupling light of a light source ( 2 ) into the light guide ( 3 b ), the light guides ( 3 b ) converging toward a shared light outcoupling surface ( 3 a ) of the light guide unit ( 3 ), the light outcoupling surface ( 3 a ) being configured to radiate light into the projection lens ( 4 ) and being essentially located in the focal plane (E) of the projection lens ( 4 ), characterized in that the light guide unit ( 3 ) comprises at least one translucent deflection element ( 6 ), which extends along the light outcoupling surface ( 3 a ) in a rib-shaped manner and protrudes beyond the light outcoupling surface ( 3 a ) in the direction of the projection lens ( 4 ), or is formed as a recess inside the light outcoupling surface ( 3 a ) counter to this direction, the deflection element ( 6 ) being designed to at least partially deflect light entering the deflection element ( 6 ) from the light outcoupling surface ( 3 a ) in the direction of the projection lens ( 4 ).

First claim

The invention claimed is:

1. A lighting device ( 1 ) for a motor vehicle headlight, comprising:
a plurality of light sources;
a light guide unit ( 3 ) that is made of a light-conducting solid body and comprises a plurality of light guides ( 3 b ); and
a downstream projection lens ( 4 ) including a focal plane (E),
wherein each light guide ( 3 b ) comprises a light incoupling surface ( 3 b ′) for coupling light of a light source ( 2 ) into the light guide ( 3 b ), the light guides ( 3 b ) converging toward a shared light outcoupling surface ( 3 a ) of the light guide unit ( 3 ), the light outcoupling surface ( 3 a ) being configured to radiate light into the projection lens ( 4 ) and being essentially located in the focal plane (E) of the projection lens ( 4 ),
wherein the light guide unit ( 3 ) comprises at least one translucent deflection element ( 6 ), which extends along the light outcoupling surface ( 3 a ) in a rib-shaped manner and protrudes beyond the light outcoupling surface ( 3 a ) in the direction of the projection lens ( 4 ), or is formed as a recess inside the light outcoupling surface ( 3 a ) counter to this direction, the deflection element ( 6 ) being designed to at least partially deflect light entering the deflection element ( 6 ) from the light outcoupling surface ( 3 a ) in the direction of the projection lens ( 4 ), the deflection element ( 6 ) having a triangular cross-section, and
wherein the triangular cross-section is delimited by three legs (S 1 , S 2 , S 3 ), a first leg (S 1 ) of the triangle extending parallel to the optical axis (X), and a second leg (S 2 ) extending parallel to the light outcoupling surface ( 3 a ).

2. The lighting device ( 1 ) according to claim 1 , wherein the deflection element ( 6 ) extends along the entire width of the light outcoupling surface ( 3 a ).

3. The lighting device ( 1 ) according to claim 1 , wherein the triangular cross-section has a third leg (S 3 ), which connects an end of the first leg (S 1 ) to an end of the second leg (S 2 ), the angle of inclination (α, α 1 , α 2 ) between the second and third legs (S 3 ) being between 5° and 40°.

4. The lighting device ( 1 ) according to claim 3 , wherein the projection lens ( 4 ) has an optical axis (X), and the light guide unit ( 3 ) is disposed in such a way that the optical axis (X) intersects the light outcoupling surface ( 3 a ), all deflection elements ( 6 ) being disposed below the optical axis (X).

5. The lighting device ( 1 ) according to claim 4 , wherein the angle of inclination (α, α 1 , α 2 ) between the second and third legs of each deflection element ( 6 ) is selected so that the angles of inclination (α, α 1 , α 2 ) of deflection elements ( 6 ) that are disposed on top of one another decrease upon approaching the optical axis (X) of the projection lens ( 4 ).

6. The lighting device ( 1 ) according to claim 5 , wherein the decrease in the angle of inclination (α, α 1 , α 2 ) of a respective deflection element ( 6 ) compared to the closest deflection element ( 6 ) located beneath the respective deflection element ( 6 ) is between 5 and 50%.

7. The lighting device ( 1 ) according to claim 1 , wherein the light guides ( 3 b ) of the light guide unit ( 3 ) are disposed in at least two rows located on top of one another, the bottommost row coupling light into an outcoupling section ( 3 a ′) of the light outcoupling surface ( 3 a ), the deflection elements ( 6 ) being only disposed within the lower half of the outcoupling section ( 3 a ′).

8. The lighting device ( 1 ) according to claim 7 , wherein the light guides ( 3 b ) of the bottommost row, in cooperation with the at least one deflection element ( 6 ) and the projection lens ( 4 ), are configured to form a high-beam light distribution.

9. The lighting device ( 1 ) according to claim 1 , wherein a light source ( 2 ) is assigned to each light incoupling surface ( 3 b ′).

10. The lighting device ( 1 ) according to claim 1 , wherein the light sources ( 2 ) are LEDs.

11. A vehicle headlight, and in particular a motor vehicle headlight, comprising the lighting device ( 1 ) according to claim 1 .

12. The vehicle headlight according to claim 11 , wherein the lighting device ( 1 ) is disposed in such a way, and the deflection elements ( 6 ) are designed in such a way, that the deflection elements ( 6 ) extend along the light outcoupling surface ( 3 a ) in a horizontal direction when the vehicle headlight is installed.

13. A motor vehicle comprising at least one lighting device ( 1 ) according to claim 1 .

14. The lighting device ( 1 ) according to claim 7 , wherein the light guides ( 3 b ) of the light guide unit ( 3 ) are disposed in three rows located on top of one another.

15. The lighting device ( 1 ) according to claim 1 , wherein the light guide unit ( 3 ) comprises two or more deflection elements ( 6 ), which are disposed on top of one another at the light outcoupling surface ( 3 a ).

16. The lighting device ( 1 ) according to claim 1 , wherein the projection lens ( 4 ), at the upper and lower faces thereof, has a trim ( 4 ′) interrupting the continuous circumference thereof to reduce the height of the projection lens ( 4 ).

17. A lighting device ( 1 ) for a motor vehicle headlight, comprising:
a plurality of light sources;
a light guide unit ( 3 ) that is made of a light-conducting solid body and comprises a plurality of light guides ( 3 b ); and
a downstream projection lens ( 4 ) including a focal plane (E),
wherein each light guide ( 3 b ) comprises a light incoupling surface ( 3 b ′) for coupling light of a light source ( 2 ) into the light guide ( 3 b ), the light guides ( 3 b ) converging toward a shared light outcoupling surface ( 3 a ) of the light guide unit ( 3 ), the light outcoupling surface ( 3 a ) being configured to radiate light into the projection lens ( 4 ) and being essentially located in the focal plane (E) of the projection lens ( 4 ),
wherein the light guide unit ( 3 ) comprises at least one translucent deflection element ( 6 ), which extends along the light outcoupling surface ( 3 a ) in a rib-shaped manner and protrudes beyond the light outcoupling surface ( 3 a ) in the direction of the projection lens ( 4 ), or is formed as a recess inside the light outcoupling surface ( 3 a ) counter to this direction, the deflection element ( 6 ) being designed to at least partially deflect light entering the deflection element ( 6 ) from the light outcoupling surface ( 3 a ) in the direction of the projection lens ( 4 ), the deflection element ( 6 ) having a triangular cross-section, and
wherein the light guide unit ( 3 ) comprises two or more deflection elements ( 6 ), which are disposed on top of one another at the light outcoupling surface ( 3 a ).

18. The lighting device ( 1 ) according to claim 17 , wherein deflection elements ( 6 ) disposed on top of one another abut one another.

19. A lighting device ( 1 ) for a motor vehicle headlight, comprising:
a plurality of light sources;
a light guide unit ( 3 ) that is made of a light-conducting solid body and comprises a plurality of light guides ( 3 b ); and
a downstream projection lens ( 4 ) including a focal plane (E),
wherein each light guide ( 3 b ) comprises a light incoupling surface ( 3 b ′) for coupling light of a light source ( 2 ) into the light guide ( 3 b ), the light guides ( 3 b ) converging toward a shared light outcoupling surface ( 3 a ) of the light guide unit ( 3 ), the light outcoupling surface ( 3 a

Assignees

• Zkw Group Gmbh

Inventors

• Plank Josef
• Taudt Lukas
• Brauner Nina

Classifications

• G02B6/0075

  Arrangements of multiple light guides (G02B6/0028 takes precedence) · CPC title

• G02B6/0046

  Tapered light guide, e.g. wedge-shaped light guide · CPC title

• F21S41/255

  Lenses with a front view of circular or truncated circular outline · CPC title

• F21S41/24 Primary

  Light guides · CPC title

• F21S41/143 Primary

  the main emission direction of the LED being parallel to the optical axis of the illuminating device · CPC title