Patent US4442380A successfully refreshed from Google Patents.
US4442380A
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Discharge tube firing device
Assignee: Mitsubishi Electric Corp
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Filing: 1981-08-28
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Granted: 1984-04-10
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Expires: 2001-08-28
Abstract
Abstract The disclosed firing device comprises a fluorescent lamp serially connected to an inductive stabilizer, a first semiconductor switch including an SCR connected across the fluorescent lamp, and a nonlinear dielectric element serially connected to a parallel combination of a PNPN switch as a second semiconductor switch and a discharging circuit across the fluorescent lamp. The discharging circuit may comprise a resistor alone. The first semiconductor switch may include a semiconductor diode and a PNPN switch and the discharging circuit may include a resistor connected across series combination of a semiconductor diode. Alternatively, the discharging circuit may include a Zener diode and a resistor serially interconnected.
Inventors
- 👤 Hiromi Adachi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:07
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/14; H05B41/16; H05B41/18; H05B41/02; H05B41/04; H05B41/042; H05B41/044; H05B41/046
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
82 words
A discharge tube firing device comprising: a discharge tube; an inductive stabilizer connected in series with said discharge tube; a first semiconductor switch and a nonlinear dielectric element each connected in parallel to said discharge tube; a second semiconductor switch connected in series with said nonlinear dielectric element and in parallel to said first semiconductor switch, said second semiconductor switch serving as a charging circuit for said nonlinear dielectric element; and a discharging circuit connected in parallel to said second semiconductor switch.
Claim 2
Dependent Claim
82 words
A discharge tube firing device comprising: a discharge tube; an inductive stabilizer connected in series with said discharge tube; a first semiconductor switch and a nonlinear dielectric element each connected in parallel to said discharge tube; a second semiconductor switch connected in series with said nonlinear dielectric element and in parallel to said first semiconductor switch, said second semiconductor switch serving as a charging circuit for said nonlinear dielectric element; and a discharging circuit connected in parallel to said second semiconductor switch.
Claim 3
Dependent Claim
17 words
A discharge tube firing device as claimed in claim 1, wherein said discharging circuit comprises a resistor.
Claim 4
Dependent Claim
44 words
A discharge tube firing device as claimed in claim 1, wherein said discharging circuit comprises: a resistor; a semiconductor diode connected in series with said resistor; and an impedance element connected in parallel to said series combination of said resistor and said semiconductor diode.
Claim 5
Dependent Claim
27 words
A discharge tube firing device as claimed in claim 1, wherein said discharging circuit comprises a resistor and a Zener diode connected in series with said resistor.
Claim 6
Dependent Claim
85 words
A discharge tube firing device comprising: a discharge tube; an inductive stabilizer connected in series with said discharge tube; a first semiconductor switch and a nonlinear dielectric element each connected in parallel to said discharge tube; a second semiconductor switch comprising a thyristor connected in series with said nonlinear dielectric element and in parallel to said first semiconductor switch, said second semiconductor switch serving as a charging circuit for said nonlinear dielectric element; and a discharging circuit connected in parallel to said second semiconductor switch.
Claim 7
Dependent Claim
85 words
A discharge tube firing device comprising: a discharge tube; an inductive stabilizer connected in series with said discharge tube; a first semiconductor switch and a nonlinear dielectric element each connected in parallel to said discharge tube; a second semiconductor switch comprising a thyristor connected in series with said nonlinear dielectric element and in parallel to said first semiconductor switch, said second semiconductor switch serving as a charging circuit for said nonlinear dielectric element; and a discharging circuit connected in parallel to said second semiconductor switch.
Claim 8
Dependent Claim
17 words
A discharge tube firing device as claimed in claim 5, wherein said discharging circuit comprises a resistor.
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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) | 1987-04-10 | 1987-10-10 | 1988-04-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-04-10 | 1991-10-10 | 1992-04-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-04-10 | 1995-10-10 | 1996-04-10 | $7700.00 | Window Closed / Lapsed |