# US 2008/0185964 A1 · High-Pressure Discharge Lamp

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2008/0185964 A1
- Document ID: US20080185964A1
- Status: Published application
- Kind: A1
- Application number: 11/913,334
- Filed: 2006-04-27
- Published: 2008-08-07
- Earliest claimed: 2005-05-02
- Assignees: Koninklijke Philips Electronics N.V.
- Inventors: Mark Josephus Lucien Maria Van Dommelen; Marten Willem Schuiteman; Leonardus Gerardus Maria Michiels
- Web page: https://patentgrep.com/patent/US20080185964A1

## CPC

- H01J 61/50: Auxiliary parts or solid material within the envelope for reducing risk of explosion upon breakage of the envelope, e.g. for use in mines
- H01J 61/34: Double-wall vessels or containers
- H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H)

## Abstract

A high-pressure discharge lamp comprising an outer envelope (1) accommodating a discharge vessel (11) having a wall with an inner and an outer surface arranged around a longitudinal axis (22); the discharge vessel enclosing, in a gastight manner, a discharge space (13) provided with an ionizable filling; the discharge vessel having first and second, mutually opposite end portions (2, 3) through which a first and a second current-supply conductor (4, 5), respectively, extend to a pair of electrodes (6, 7) arranged in the discharge space. The lamp according to the invention has the special feature that the discharge vessel is provided with a weakening line (20) extending along at least a part of the circumference of the discharge vessel (11) so as to allow the discharge vessel to break into two parts along said weakening line in the case of breakage of the discharge vessel.

## Claims

### Claim 1

A high-pressure discharge lamp comprising
an outer envelope accommodating a discharge vessel having a wall with an inner and an outer surface arranged around a longitudinal axis;
the discharge vessel enclosing, in a gastight manner, a discharge space provided with an ionizable filling;
the discharge vessel having first and second, mutually opposite end portions through which a first and a second current-supply conductor, respectively, extend to a pair of electrodes arranged in the discharge space,
characterized in that the wall of the discharge vessel is provided with a weakening mark on at least a part of its circumference so as to allow the discharge vessel to break along a line over said weakening mark in the case of breakage of the discharge vessel.

### Claim 2 (depends on 1)

A high-pressure discharge lamp according to claim 1, wherein the weakening mark has a shape of a line formed by a groove or a series of spots extending along a line.

### Claim 3 (depends on 1)

A high-pressure discharge lamp according to claim 1, wherein the weakening mark is shaped as one or more blind holes.

### Claim 4 (depends on 2)

A high-pressure discharge lamp according to claim 2, wherein said weakening line extends along the entire circumference of the wall of the discharge vessel.

### Claim 5 (depends on 1)

A high-pressure discharge lamp according to claim 1, wherein said weakening mark is located at the inner surface of the wall of the discharge vessel.

### Claim 6 (depends on 1)

A high-pressure discharge lamp according to claim 1, wherein said weakening mark is located at the outer surface of the wall of the discharge vessel.

### Claim 7 (depends on 1)

A high-pressure discharge lamp according to claim 1, wherein the weakening mark is a recess in the surface of the wall of the discharge vessel, which recess has a depth varying between 0.05 mm and 0.7 mm, and is particularly less than 0.3 mm.

### Claim 8 (depends on 1)

A high-pressure discharge lamp according to claim 1, wherein the weakening mark is a recess in the surface of the wall of the discharge vessel, with a largest width varying between 0. 1 mm and 1 mm, particularly between 0.2 mm and 0.5 mm.

### Claim 9 (depends on 1)

A high-pressure discharge lamp according to claim 1, wherein said weakening mark is located on the wall of the discharge vessel at least substantially halfway the first and the second end portion of the discharge vessel.