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US5500576A Expired / Lapsed US ⏱️ 0.0 years remaining

Low height ballast for fluorescent lamps

Assignee: Universal Lighting Technologies Inc
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Filing: 1994-04-15
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Granted: 1996-03-19
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Expires: 2014-04-15
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Abstract

Abstract An electronic ballast has a high voltage portion and a low voltage portion. The high voltage portion includes a converter, having a variable frequency boost circuit, and a half-bridge, driven inverter having a series resonant, direct coupled output. The low voltage portion of the ballast includes a control circuit and fault detectors for shutting off the boost circuit and the inverter circuit. The fault detectors consume very little power when the ballast and lamp are functioning normally. Separate magnetics are used for boost, inverter, and output. Each magnetic is essentially cubic in shape and carries as little current as possible.

Inventors

  • 👤 Randy G. Russell
  • 👤 Kent E. Crouse
  • 👤 Peter W. Shackle
  • 👤 Ronald J. Bezdon

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 06:53
CPC Classifications
G; G05; G05F; G05F1/00; G05F1/70; H; H02; H02M; H02M1/00; H02M1/42; H02M1/4208; H02M1/4225; H05; H05B; H05B41/00; H05B41/14; H05B41/26; H05B41/28; Y; Y02; Y02B; Y02B70/00; Y02B70/10; Y10; Y10S; Y10S315/00; Y10S315/05

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 145 words
An electronic ballast for powering a gas discharge lamp from an AC input voltage, said ballast having a height equal to or less than one inch, a power factor≧0.9, and a harmonic distortion≦10 percent, said ballast comprising: a converter for converting said AC input voltage into pulses of direct current at a high voltage, said converter including means for varying the current drawn by said converter in phase with said AC input voltage by changing the frequency of said pulses; a capacitor coupled to the output of said converter for storing said high voltage; a driven, half-bridge inverter powered by the energy stored in said capacitor, said inverter having a series resonant, direct coupled output for connection to said lamp; wherein said converter includes a first magnetic and said inverter includes a second magnetic and said first magnetic and said second magnetic have separate cores.
Claim 2
Dependent Claim 145 words
An electronic ballast for powering a gas discharge lamp from an AC input voltage, said ballast having a height equal to or less than one inch, a power factor≧0.9, and a harmonic distortion≦10 percent, said ballast comprising: a converter for converting said AC input voltage into pulses of direct current at a high voltage, said converter including means for varying the current drawn by said converter in phase with said AC input voltage by changing the frequency of said pulses; a capacitor coupled to the output of said converter for storing said high voltage; a driven, half-bridge inverter powered by the energy stored in said capacitor, said inverter having a series resonant, direct coupled output for connection to said lamp; wherein said converter includes a first magnetic and said inverter includes a second magnetic and said first magnetic and said second magnetic have separate cores.
Claim 3
Dependent Claim 33 words
The ballast as set forth in claim 1 wherein said inverter is driven and said ballast further comprises: a control circuit including an output coupled to said converter for shutting off said converter.
Claim 4
Dependent Claim 32 words
The ballast as set forth in claim 2 wherein said control circuit includes a third magnetic, wherein said third magnetic has a core separate from said first magnetic and said second magnetic.
Claim 5
Dependent Claim 17 words
The ballast as set forth in claim 3 wherein each magnetic is wound on an EE core.
Claim 6
Dependent Claim 16 words
The ballast as set forth in claim 4 wherein the magnetics have an approximately cubic shape.
Claim 7
Dependent Claim 37 words
The ballast as set forth in claim 2 wherein said converter also converts said alternating current into a direct current at a low voltage and said control circuit is powered by said direct current at low voltage.
Claim 8
Dependent Claim 26 words
The ballast as set forth in claim 2 wherein said control circuit includes circuitry for shutting off said ballast in the event of a fault condition.
Claim 9
Dependent Claim 33 words
The ballast as set forth in claim 7 and further including a sense capacitor in series with said lamp, wherein said sense capacitor is coupled to said circuitry for shutting off said ballast.
Claim 10
Dependent Claim 23 words
The ballast as set forth in claim 1 wherein the frequency of said converter varies with the amplitude of said AC input voltage.
Claim 11
Dependent Claim 136 words
An electronic ballast for powering a gas discharge lamp from an AC input voltage, said ballast having a height equal to or less than one inch, said ballast comprising: a self-oscillating converter for converting said AC input voltage into pulses of direct current at a high voltage, said converter including means for varying the current drawn by said converter in phase with said AC input voltage by changing the frequency of said pulses; a driven, half-bridge inverter, said inverter having a series resonant, direct coupled output for connection to said lamp; a control circuit coupled to said inverter for driving said inverter at a predetermined frequency; said converter includes a first magnetic, said direct coupled output includes a second magnetic, and said control circuit includes a third magnetic, wherein each magnetic is on a separate core.
Claim 12
Dependent Claim 136 words
An electronic ballast for powering a gas discharge lamp from an AC input voltage, said ballast having a height equal to or less than one inch, said ballast comprising: a self-oscillating converter for converting said AC input voltage into pulses of direct current at a high voltage, said converter including means for varying the current drawn by said converter in phase with said AC input voltage by changing the frequency of said pulses; a driven, half-bridge inverter, said inverter having a series resonant, direct coupled output for connection to said lamp; a control circuit coupled to said inverter for driving said inverter at a predetermined frequency; said converter includes a first magnetic, said direct coupled output includes a second magnetic, and said control circuit includes a third magnetic, wherein each magnetic is on a separate core.
Claim 13
Dependent Claim 37 words
The ballast as set forth in claim 10 wherein said converter also converts said alternating current into a direct current at a low voltage and said control circuit is powered by said direct current at low voltage.
Claim 14
Dependent Claim 30 words
The ballast as set forth in claim 10 wherein said converter includes means for varying the frequency of said converter in phase with the amplitude of said AC input voltage.
Claim 15
Dependent Claim 41 words
The ballast as set forth in claim 10 wherein said converter includes: a full wave rectifier for rectifying said AC input voltage; and means for varying said direct current in phase with a ripple component of the rectified AC input voltage.

References Cited (Backward Citations)

US5214355A Cited
US4277728A Cited
US4251752A Cited
US4562383A Cited
US4523131A Cited
US5363020A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-03-19 1999-09-18 2000-03-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-03-19 2003-09-18 2004-03-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-03-19 2007-09-18 2008-03-19 $7700.00 Window Closed / Lapsed

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