US3760224A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Discharge lamp igniting circuit
Assignee: Tokai Rika Co Ltd
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Filing: 1971-08-05
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Granted: 1973-09-18
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Expires: 1991-08-05
Abstract
Abstract A discharge lamp igniting circuit in a discharge lamp of short tube length and capable of being ignited only by pre-heating a filament thereof, comprising a stabilizer winding having a secondary winding; a switching element connected to the discharge lamp at a terminal of one filament of said discharge lamp which is not connected to a power supply; and a diode connected to said secondary winding to keep said switching element conductive for at least one cycle until the discharge lamp is started; said secondary winding of the stabilizer winding, said filament of the discharge lamp, said switching element and said diode forming a closed loop to promote pre-heating of the filament and energize the stabilizer winding throughout all cycles by a short-circuit current flowing through the secondary winding, the switching element and the diode. With such a discharge lamp igniting circuit, a kick voltage produced at a time of ignition of the discharge lamp can be well prevented to eliminate possible darkening of the discharge lamp at its end portions.
Inventors
- 👤 H Tanaka
- 👤 T Shimizu
- 👤 M Iwakura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:45
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/02; H05B41/04; H05B41/042; H05B41/044; Y; Y10; Y10S; Y10S315/00; Y10S315/05
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
199 words
In a discharge lamp of short tube length responsive to an AC power supply voltage thereacross for being ignited by pre-heating a filament thereof and without application of a kick voltage thereto, a discharge lamp igniting circuit comprising a stabilizer winding connected in circuit with the power supply and terminals of the filaments of the lamp and having a secondary winding; a switching element having a breakdown voltage and connected to the discharge lamp at a further terminal of one filament of said discharge lamp for conducting through said stabilizer winding due to first half cycles of said power supply; and a diode connected to said secondary winding to keep said switching element conductive for at least one cycle until the discharge lamp is started; said secondary winding of the stabilizer winding, said one filament of the discharge lamp, said switching element and said diode forming a closed loop to promote pre-heating of the filament and maintain energization of the stabilizer winding throughout all cycles prior to lamp ignition by a current flowing through the secondary winding, the switching element and the diode, thereby preventing a kick voltage from being produced at a time of igniting the discharge lamp.
Claim 2
Dependent Claim
199 words
In a discharge lamp of short tube length responsive to an AC power supply voltage thereacross for being ignited by pre-heating a filament thereof and without application of a kick voltage thereto, a discharge lamp igniting circuit comprising a stabilizer winding connected in circuit with the power supply and terminals of the filaments of the lamp and having a secondary winding; a switching element having a breakdown voltage and connected to the discharge lamp at a further terminal of one filament of said discharge lamp for conducting through said stabilizer winding due to first half cycles of said power supply; and a diode connected to said secondary winding to keep said switching element conductive for at least one cycle until the discharge lamp is started; said secondary winding of the stabilizer winding, said one filament of the discharge lamp, said switching element and said diode forming a closed loop to promote pre-heating of the filament and maintain energization of the stabilizer winding throughout all cycles prior to lamp ignition by a current flowing through the secondary winding, the switching element and the diode, thereby preventing a kick voltage from being produced at a time of igniting the discharge lamp.
Claim 3
Dependent Claim
18 words
A discharge lamp igniting circuit as claimed in claim 1 wherein said secondar winding is an autotransformer winding.
Claim 4
Dependent Claim
21 words
A discharge lamp igniting circuit as claimed in claim 1 wherein said secondary winding is a winding of a two-winding transformer.
Claim 5
Dependent Claim
17 words
A discharge lamp igniting Device as claimed in claim 1 wherein said switching element is a thyristor.
Claim 6
Dependent Claim
22 words
A discharge lamp igniting switch as claimed in claim 1 wherein said discharge lamp has power dissipation of 10 watts or less.
Claim 7
Dependent Claim
151 words
In a discharge lamp igniting circuit for a lamp of short tube length and capable of being ignited by preheating a filament thereof at the rated voltage of the lamp and without a kick voltage applied thereto, such lamp having a pair of filaments, each filament having a pair of terminals, the combination comprising: a stabilizer winding and means connecting same in circuit with a terminal of each lamp filament to an AC power supply for maintaining the lamp conductive after ignition, said stabilizer winding having a secondary winding; a thyristor switching element and a first diode connected end to end between said filaments and to the remaining terminals thereof and being a portion of the flow path of preheating current through said filaments and stabilizer winding in one portion of a cycle of said power supply; a second diode connecting said end of said switching element to said secondary winding.
Claim 8
Dependent Claim
151 words
In a discharge lamp igniting circuit for a lamp of short tube length and capable of being ignited by preheating a filament thereof at the rated voltage of the lamp and without a kick voltage applied thereto, such lamp having a pair of filaments, each filament having a pair of terminals, the combination comprising: a stabilizer winding and means connecting same in circuit with a terminal of each lamp filament to an AC power supply for maintaining the lamp conductive after ignition, said stabilizer winding having a secondary winding; a thyristor switching element and a first diode connected end to end between said filaments and to the remaining terminals thereof and being a portion of the flow path of preheating current through said filaments and stabilizer winding in one portion of a cycle of said power supply; a second diode connecting said end of said switching element to said secondary winding.
Claim 9
Dependent Claim
27 words
A discharge lamp igniting device as claimed in claim 6, in which said diodes connect back to back at the ends thereof connected to said switching element.
Claim 10
Dependent Claim
58 words
A discharge lamp igniting device as claimed in claim 6, in which said switching element, the filament connected thereto, said second diode and said secondary winding define a closed series loop for flowing current therethrough for the remaining portion of said cycle, whereby preheating current flows continuously through said switching element during preheating and ignition of said lamp.
References Cited (Backward Citations)
US3644780A
Cited
US3631317A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-17 | 1977-03-19 | 1977-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-17 | 1981-03-19 | 1981-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-17 | 1985-03-19 | 1985-09-18 | $7700.00 | Window Closed / Lapsed |