Patent US4661746A successfully refreshed from Google Patents.
US4661746A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrodeless low-pressure discharge lamp
Assignee: US Philips Corp
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Filing: 1985-06-05
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Granted: 1987-04-28
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Expires: 2005-06-05
Abstract
Abstract An electrodeless low-pressure discharge lamp comprising a lamp vessel (1) sealed in a vacuum-tight manner and filled at least with a metal vapor and a rare gas, the lamp being provided also with a cylindrical core (2) of magnetic material, such as ferrite, a winding (4) arranged to surround the core (2) and an electrical supply unit connected thereto for producing during operation of the lamp an electrical field in the lamp vessel (1). The supply unit is located in a thin-walled metal housing (8) provided in a wall portion (9) of synthetic material, which is partly of conical shape and is provided at its end with an Edison lamp cap (10), and the core (2) accommodates a rod-shaped or tubular body (11) of thermally conducting material connected to the housing (8). In order to improve the ignition properties of the lamp, an electrical insulator (12) is provided between the end of the body (11) and the wall of the housing (8).
Inventors
- 👤 Pieter Postma
- 👤 Johannes A. J. M. van Vliet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:18
CPC Classifications
H; H01; H01J; H01J65/00; H01J65/04; H01J65/042; H01J65/048
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
119 words
An electrodeless low-pressure discharge lamp comprising a lamp vessel which is sealed in a gastight manner and is filled at least with a metal vapour and a rare gas and an electrical supply unit which is connected to a winding around a cylindrical core of magnetic material for producing during operation an electrical field in the lamp vessel, said supply unit being located in a metal housing forming part of the lamp, and said core of magnetic material accommodating a rod-shaped body of thermally conducting material connected to the housing, characterized in that the part of the thermally conducting body located at the area of the winding is electrically insulated from the metal housing accommodating the electrical supply unit.
Claim 2
Dependent Claim
119 words
An electrodeless low-pressure discharge lamp comprising a lamp vessel which is sealed in a gastight manner and is filled at least with a metal vapour and a rare gas and an electrical supply unit which is connected to a winding around a cylindrical core of magnetic material for producing during operation an electrical field in the lamp vessel, said supply unit being located in a metal housing forming part of the lamp, and said core of magnetic material accommodating a rod-shaped body of thermally conducting material connected to the housing, characterized in that the part of the thermally conducting body located at the area of the winding is electrically insulated from the metal housing accommodating the electrical supply unit.
Claim 3
Dependent Claim
34 words
An electrodeless low-pressure discharge lamp as claimed in claim 1, characterized in that an electrical insulator is provided between the lower side of the thermally conducting body and the wall of the metal housing.
Claim 4
Dependent Claim
46 words
An electrodeless low-pressure discharge lamp as claimed in claim 2, characterized in that the electrical insulator comprises a layer which extends between the wall of the metal housing facing the lamp vessel and the lower side of the lamp vessel, this layer further being thermally insulating.
Claim 5
Dependent Claim
41 words
An electrodeless low-pressure discharge lamp as claimed in claim 3, characterized in that the thermally conducting body extends beyond the end of the cylindrical core facing the metal housing, this thermally conducting body being provided in situ with a thickened part.
Claim 6
Dependent Claim
33 words
An electrodeless low-pressure discharge lamp as claimed in claim 4, characterized in that the electrical insulator consists of a cylinder of synthetic material disposed between the end of the body and the housing.
Claim 7
Dependent Claim
33 words
An electrodeless low-pressure discharge lamp as claimed in claim 2, characterized in that the electrical insulator consists of a cylinder of synthetic material disposed between the end of the body and the housing.
Claim 8
Dependent Claim
41 words
An electrodeless low-pressure discharge lamp as claimed in claim 2, characterized in that the thermally conducting body extends beyond the end of the cylindrical core facing the metal housing, this thermally conducting body being provided in situ with a thickened part.
Claim 9
Dependent Claim
41 words
An electrodeless low-pressure discharge lamp as claimed in claim 1, characterized in that the thermally conducting body extends beyond the end of the cylindrical core facing the metal housing, this thermally conducting body being provided in situ with a thickened part.
References Cited (Backward Citations)
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US4119889A
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US4189661A
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US4266167A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-04-27 | 1990-10-27 | 1991-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-27 | 1994-10-27 | 1995-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-27 | 1998-10-27 | 1999-04-28 | $7700.00 | Window Closed / Lapsed |