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US4977349A Expired / Lapsed US ⏱️ 0.0 years remaining

Low-pressure mercury vapor discharge lamp

Assignee: Toshiba Corp
•
Filing: 1989-09-26
•
Granted: 1990-12-11
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Expires: 2009-09-26
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Abstract

Abstract A low-pressure mercury vapor discharge lamp. The lamp includes at least two tube sections substantially parallel to each other for holding a quantity of mercury vapor, sealings for sealing one end of each of two of the tube sections, discharge electrodes for activating the mercury vapor for generating a luminescent discharge, a reduced diameter connecting tube for sealing the remaining ends of the tube sections to one another in successive pairs, and an amalgam for maintaining the mercury vapor pressure at a level which maintains the luminance of the discharge at a substantially constant value.

Inventors

  • 👤 Masahiko Asakura
  • 👤 Kimio Shiraiwa
  • 👤 Yoichi Hattori
  • 👤 Naotosi Toume

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 20:22
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/70; H01J61/02; H01J61/24; H01J61/28; H01J61/30; H01J61/33; H01J61/72

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 148 words
A low-pressure mercury vapor discharge lamp, comprising: at least two substantially parallel tube sections for holding a quantity of mercury vapor, said tube sections being exposed to the atmosphere; sealing means for sealing one end of each of two of the tube sections; stems disposed at each of said sealed ends of said tubes, at least one of said stems including a receptacle disposed at least partially exterior said tube sections; connecting tube means for sealingly connecting the other ends of the tube sections to one another in successive pairs, portions of said connecting tube means having diameters that are less than the diameters of corresponding ones of the tube sections; and an amalgam positioned in the portion of said receptacle that is exterior said tube sections for maintaining the mercury vapor pressure at a level which maintains the luminance of the discharge at a substantially constant value.
Claim 2
Dependent Claim 148 words
A low-pressure mercury vapor discharge lamp, comprising: at least two substantially parallel tube sections for holding a quantity of mercury vapor, said tube sections being exposed to the atmosphere; sealing means for sealing one end of each of two of the tube sections; stems disposed at each of said sealed ends of said tubes, at least one of said stems including a receptacle disposed at least partially exterior said tube sections; connecting tube means for sealingly connecting the other ends of the tube sections to one another in successive pairs, portions of said connecting tube means having diameters that are less than the diameters of corresponding ones of the tube sections; and an amalgam positioned in the portion of said receptacle that is exterior said tube sections for maintaining the mercury vapor pressure at a level which maintains the luminance of the discharge at a substantially constant value.
Claim 3
Dependent Claim 44 words
The low-pressure mercury vapor discharge lamp of claim 1 wherein the connecting tube means includes at least one generally U-shaped tube joining two tube sections, and having a midpoint, the diameter of the U-shaped tube gradually increasing from the midpoint to each end thereof.
Claim 4
Dependent Claim 31 words
The low-pressure mercury vapor discharge lamp of claim 2 wherein the diameter of the U-shaped tube at each end thereof is equal to the diameter of the tube section connected thereto.
Claim 5
Dependent Claim 37 words
The low-pressure mercury vapor discharge lamp of claim 3 wherein the diameter of the U-shaped tube at the midpoint is about 20 mm, and the diameter at the ends of the U-shaped tube is approximately 24 mm.
Claim 6
Dependent Claim 24 words
The low-pressure mercury vapor discharge lamp of claim 4 wherein each tube sections includes a glass wall having a thickness of about 1 mm.
Claim 7
Dependent Claim 15 words
The low-pressure mercury vapor discharge lamp of claim 1 wherein the amalgam is indium-bismuth amalgam.
Claim 8
Dependent Claim 20 words
The low-pressure mercury vapor discharge lamp of claim 6 wherein the indium-bismuth amalgam includes 0.75 to 6 weight percent mercury.
Claim 9
Dependent Claim 56 words
The low-pressure mercury vapor discharge lamp of claim 1, wherein said receptacle includes an elongated pipe extending outward from said stem exterior said tube sections, said pipe being sealed at one end thereof and having a constricted portion, said amalgam being positioned between the sealed end of said pipe and the constricted portion of said pipe.
Claim 10
Dependent Claim 25 words
The low-pressure mercury vapor discharge lamp of claim 8, wherein the other end of said pipe is opened to the interior of said tube sections.
Claim 11
Dependent Claim 33 words
The low-pressure mercury vapor discharge lamp of claim 9, further comprising an electrode supported on each of each stems within said tube sections for activating the mercury vapor for generating a luminescent discharge.
Claim 12
Dependent Claim 132 words
A low-pressure mercury vapor discharge lamp, comprising: at least two substantially parallel tube sections for holding a quantity of mercury vapor, said tube sections being exposed to the atmosphere; sealing means for sealing one end of each of two of the tube sections; means for activating the mercury vapor for generating a luminescent discharge; connecting tube means for sealingly connecting the other ends of the tube sections to one another in successive pairs, portions of said connecting tube means having diameters that are less than the diameters of corresponding ones of the tube sections; and an indium-bismuth-silver amalgam positioned in one of the tube sections of each pair of tube sections for maintaining the mercury vapor pressure at a level which maintains the luminance of the discharge at a substantially constant value.
Claim 13
Dependent Claim 132 words
A low-pressure mercury vapor discharge lamp, comprising: at least two substantially parallel tube sections for holding a quantity of mercury vapor, said tube sections being exposed to the atmosphere; sealing means for sealing one end of each of two of the tube sections; means for activating the mercury vapor for generating a luminescent discharge; connecting tube means for sealingly connecting the other ends of the tube sections to one another in successive pairs, portions of said connecting tube means having diameters that are less than the diameters of corresponding ones of the tube sections; and an indium-bismuth-silver amalgam positioned in one of the tube sections of each pair of tube sections for maintaining the mercury vapor pressure at a level which maintains the luminance of the discharge at a substantially constant value.
Claim 14
Dependent Claim 20 words
The low-pressure mercury vapor discharge lamp of claim 11, wherein the indium-bismuth-silver amalgam includes 0.75 to 6 weight percent mercury.
Claim 15
Dependent Claim 124 words
A low-pressure mercury vapor discharge lamp, comprising: at least two substantially parallel tube sections for holding a quantity of mercury vapor; sealing means for sealing one end of each of two of the tube sections; means for activating the mercury vapor for generating a luminescent discharge; connecting tube means for sealingly connecting the other ends of the tube sections to one another in successive pairs, portions of said connecting tube means having diameters that are less than the diameters of corresponding ones of the tube sections; and an indium-bismuth-silver amalgam positioned in one of the tube sections of each pair of tube sections for maintaining the mercury vapor pressure at a level which maintains the luminance of the discharge at a substantially constant value.
Claim 16
Dependent Claim 124 words
A low-pressure mercury vapor discharge lamp, comprising: at least two substantially parallel tube sections for holding a quantity of mercury vapor; sealing means for sealing one end of each of two of the tube sections; means for activating the mercury vapor for generating a luminescent discharge; connecting tube means for sealingly connecting the other ends of the tube sections to one another in successive pairs, portions of said connecting tube means having diameters that are less than the diameters of corresponding ones of the tube sections; and an indium-bismuth-silver amalgam positioned in one of the tube sections of each pair of tube sections for maintaining the mercury vapor pressure at a level which maintains the luminance of the discharge at a substantially constant value.
Claim 17
Dependent Claim 21 words
The low-pressure mercury vapor discharge lamp of claim 13, wherein the indium bismuth-silver amalgam includes 0.75 to 6 weight percent mercury.

References Cited (Backward Citations)

US4353007A Cited
GB2023924A Cited
JPS5553053A Cited
US4288715A Cited
JPS5748555A Cited
US4481442A Cited
US4636686A Cited
JPS60225346A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-12-10 1994-06-11 1994-12-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-12-10 1998-06-11 1998-12-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-12-10 2002-06-11 2002-12-11 $7700.00 Window Closed / Lapsed

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