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US3858075A Expired / Lapsed US ⏱️ 0.0 years remaining

Low pressure mercury vapor discharge lamp

Assignee: Osram GmbH
•
Filing: 1974-01-16
•
Granted: 1974-12-31
•
Expires: 1994-01-16
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Abstract

Abstract An improved low pressure mercury vapor discharge lamp having an elongated vitreous envelope with electrodes sealed into its ends. At least one of said electrodes is connected to an outwardly flared stem which is sealed to one end of the envelope. The stem is partially coated with an amalgam-forming metal which becomes the main amalgam during lamp operation. The stem is also coated with a ceramic between the amalgam-forming metal and the electrode to prevent migration of the amalgam during operation.

Inventors

  • 👤 R Herrmann
  • 👤 G Sohring

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 07:38
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/70; H01J61/72

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 72 words
IN A LOW-PRESSURE MERCURY VAPOR DISCHARGE LAMP COMPRISING AN ELONGATED VITREOUS ENVELOPE HAVING ELECTRODES SEALED INTO ITS ENDS, AT LEAST ONE OF SAID ELECTRODES BEING CONNECTED TO AN OUTWARDLY FLARED STEM SEALED TO ONE END OF SAID ENVELOPED AND SAID STEM BEING PARTIALLY COATED WITH AN AMALGAM-FOAMING METAL WHICH BECOMES THE MAIN AMALGAM DURING LAMP OPERATION, THE IMPROVEMENT POSITIONING A CERAMIC COATING ON SAID STEM BETWEEN SAID AMALGAM-FORMING METAL AND SAID ELECTRODE.
Claim 2
Dependent Claim 72 words
IN A LOW-PRESSURE MERCURY VAPOR DISCHARGE LAMP COMPRISING AN ELONGATED VITREOUS ENVELOPE HAVING ELECTRODES SEALED INTO ITS ENDS, AT LEAST ONE OF SAID ELECTRODES BEING CONNECTED TO AN OUTWARDLY FLARED STEM SEALED TO ONE END OF SAID ENVELOPED AND SAID STEM BEING PARTIALLY COATED WITH AN AMALGAM-FOAMING METAL WHICH BECOMES THE MAIN AMALGAM DURING LAMP OPERATION, THE IMPROVEMENT POSITIONING A CERAMIC COATING ON SAID STEM BETWEEN SAID AMALGAM-FORMING METAL AND SAID ELECTRODE.
Claim 3
Dependent Claim 46 words
The lamp of claim 1 wherein said amalgam-forming meal is in the form of an annulus covering at least part of the flared portion of said stem, and said ceramic coating is an adjacent annular coating; and wherein said amalgam-forming annular coating is a spray-deposited coating.
Claim 4
Dependent Claim 12 words
The lamp of claim 2 wherein said amalgam-forming metal coating is indium.
Claim 5
Dependent Claim 11 words
The lamp of claim 3 wherein said ceramic material is ZrO2.
Claim 6
Dependent Claim 11 words
The lamp of claim 3 wherein said ceramic material is SiO2.
Claim 7
Dependent Claim 11 words
The lamp of claim 1 wherein said ceramic material is SiO2.
Claim 8
Dependent Claim 11 words
The lamp of claim 1 wherein said ceramic material is ZrO2.
Claim 9
Dependent Claim 11 words
The lamp of claim 1 wherein said amalgam-forming metatl is indium.
Claim 10
Dependent Claim 11 words
The lamp of claim 2 wherein said ceramic material is ZrO2.
Claim 11
Dependent Claim 11 words
The lamp of claim 2 wherein said ceramic material is SiO2.

References Cited (Backward Citations)

US3548241A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-12-30 1978-07-01 1978-12-31 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-12-30 1982-07-01 1982-12-31 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-12-30 1986-07-01 1986-12-31 $7700.00 Window Closed / Lapsed

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