Gas-discharge lamp for a vehicle headlamp

Patent metadata

Field	Value
Publication number	US-10325769-B2
Application number	US-201515533643-A
Country	US
Kind code	B2
Filing date	Dec 4, 2015
Priority date	Dec 12, 2014
Publication date	Jun 18, 2019
Grant date	Jun 18, 2019

Abstract

The invention describes a gas-discharge lamp comprising an inner vessel enclosing a pair of electrodes separated by a gap; and an outer vessel enclosing the inner vessel; and wherein the lamp comprises a lateral stripe arranged on the surface of a vessel such that the lateral stripe lies below a horizontal plane through a longitudinal axis through the center of the lamp, and wherein the lateral stripe extends essentially only over a region corresponding to the gap between the electrodes.

First claim

The invention claimed is:

1. A gas-discharge lamp for horizontal mounting in a vehicle headlamp comprising:
an inner vessel enclosing a pair of electrodes separated by a gap; and
an outer vessel enclosing the inner vessel;

wherein the lamp comprises a lateral stripe for blocking light of the lamp from appearing above a bright/dark cut-off line of a front beam of the vehicle headlamp, with the lateral stripe being arranged on a surface of the inner or outer vessel below a horizontal plane through a longitudinal axis through the center of the lamp, and wherein the lateral stripe extends
over a region corresponding to the gap between the electrodes, and
by a distance of at most 1.0 mm beyond the gap in the direction of an inner end region of the lamp, and
by a distance of at most 2.0 mm beyond the gap in the direction of an outer end region of the lamp.

2. A lamp according to claim 1 , wherein the lateral stripe has a length of at most 6.0 mm, preferably at most 5.0 mm.

3. A lamp according to claim 1 , wherein the lateral stripe has a height of 2.0±0.7 mm.

4. A lamp according to claim 1 , wherein the lamp comprises two lateral stripes, one on each side of the inner or outer vessel.

5. A lamp according to claim 4 , wherein the lateral stripes have essentially identical dimensions.

6. A lamp according to claim 1 , wherein the lateral stripe extends by a distance of at most 0.5 mm in the direction of the inner end region of the lamp.

7. A lamp according to claim 1 , wherein the lateral stripe extends by a distance of at most 0.5 mm in the direction of the outer end region of the lamp.

8. A lamp according to claim 1 , wherein the lateral stripe comprises an opaque material.

9. A lamp according to claim 1 , wherein the lamp is free of any coating about the inner end region.

10. A lamp according to claim 1 , further comprising a circumferential stripe arranged on a surface of the inner or outer vessel in the inner region of the lamp, and wherein the circumferential stripe is separate from the lateral stripe by a distance of at least 1.5 mm.

11. A lamp according to claim 1 , with a nominal power of 35 W, for which lamp
the capacity of the inner discharge vessel is greater than or equal to 15 μl and less than or equal to 23 μl;
the inner diameter of the inner discharge vessel comprises at least 2.2 mm and at most 2.8 mm; and
the outer diameter of the inner discharge vessel comprises at least 5.2 mm and at most 5.8 mm.

12. A lamp according to claim 1 , wherein the lateral stripe is applied to an outer surface of the outer vessel of the lamp.

Assignees

• Koninklijke Philips Nv

Inventors

• Kuepper Lukas
• Dohmen Hans-Alo
• Lenzen Thorsten Erich

Classifications

• H01J61/34 Primary

  Double-wall vessels or containers · CPC title

• H01J61/54

  Igniting arrangements, e.g. promoting ionisation for starting · CPC title

• H01J61/35

  provided with coatings on the walls thereof; Selection of materials for the coatings (using coloured coatings H01J61/40; using luminescent coatings H01J61/42) · CPC title

• F21S41/43

  characterised by the shape thereof · CPC title

• H01J61/025 Primary

  Associated optical elements · CPC title