US3746920A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lightweight xenon lamp igniter
Assignee: United States Department of the Navy
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Filing: 1971-11-24
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Granted: 1973-07-17
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Expires: 1991-11-24
Abstract
Abstract A high voltage diode in combination with a vacuum relay and a low voltage power supply provide an ignition circuit for a Xenon lamp, eliminating the use of a heavy and continuous duty high voltage pulse transformer. This permits appreciable reduction in weight of the ignition circuit, which also produces much less radio frequency interference than a conventional spark discharge type igniter.
Inventors
- 👤 J Flatley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:25
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/02; H05B41/04; H05B41/042; Y; Y10; Y10S; Y10S315/00; Y10S315/05; Y10S315/07
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
296 words
An igniter circuit for a gas filled electric lamp having a first electrode and a grounded second electrode comprising: a first power supply adapted to provide a D.C. voltage; a current regulator having its input connected to the output of said first power supply and its output coupled to the first electrode of said lamp; a second power supply for stepping up the output voltage of said first power supply, the input of said second power supply being coupled to the output of said first power supply and the output of said second power supply being coupled to said first electrode of said lamp; a timing circuit including a unijunction transistor having a first ohmic contact coupled to the output of said first power supply, an emitter contact coupled to the output of said second power supply, and a second ohmic contact; means for maintaining the second ohmic contact of said unijunction transistor above ground potential; a first normally closed switching element coupling the output of said first power supply to the input of said second power supply and to said first ohmic contact; a second normally open switching element coupling the output of said current regulator to the output of said second power supply and to said first electrode; means for isolating the output of said current regulator from the output of said second power supply; a voltage pulse transformer having its primary winding coupled to said second ohmic contact and its secondary winding coupled to said first electrode; and means driven by said timing circuit for actuating said first and second switching elements a predetermined time after energization of said second power supply, thereby applying the output of said current regulator and disconnecting the output of said second power supply from said first electrode.
Claim 2
Dependent Claim
296 words
An igniter circuit for a gas filled electric lamp having a first electrode and a grounded second electrode comprising: a first power supply adapted to provide a D.C. voltage; a current regulator having its input connected to the output of said first power supply and its output coupled to the first electrode of said lamp; a second power supply for stepping up the output voltage of said first power supply, the input of said second power supply being coupled to the output of said first power supply and the output of said second power supply being coupled to said first electrode of said lamp; a timing circuit including a unijunction transistor having a first ohmic contact coupled to the output of said first power supply, an emitter contact coupled to the output of said second power supply, and a second ohmic contact; means for maintaining the second ohmic contact of said unijunction transistor above ground potential; a first normally closed switching element coupling the output of said first power supply to the input of said second power supply and to said first ohmic contact; a second normally open switching element coupling the output of said current regulator to the output of said second power supply and to said first electrode; means for isolating the output of said current regulator from the output of said second power supply; a voltage pulse transformer having its primary winding coupled to said second ohmic contact and its secondary winding coupled to said first electrode; and means driven by said timing circuit for actuating said first and second switching elements a predetermined time after energization of said second power supply, thereby applying the output of said current regulator and disconnecting the output of said second power supply from said first electrode.
Claim 3
Dependent Claim
52 words
The igniter circuit of claim 1 wherein the means for isolating the output of said current regulator from the output of said second power supply is a first diode having its anode connected to the output of said current regulator and its cathode coupled to the output of said second power supply.
Claim 4
Dependent Claim
45 words
The igniter circuit of claim 2 wherein a second diode is interposed between the secondary winding of said pulse transformer and output of said second power supply to protect said second power supply from a voltage pulse from the secondary winding of said pulse transformer.
Claim 5
Dependent Claim
38 words
The igniter circuit of claim 3 wherein said first switching element comprises a firsT solenoid relay having its first terminal connected to the output of said first power supply and its second terminal connected to said timing circuit.
Claim 6
Dependent Claim
52 words
The igniter circuit of claim 4 wherein said second switching element comprises a second solenoid vacuum relay, the solenoid of said second relay having its first terminal connected to the output of said first power supply and its second terminal connected to the second terminal of the solenoid of said first relay.
Claim 7
Dependent Claim
62 words
The igniter circuit of claim 5 wherein the timing circuit further comprises: a first SCR having its anode coupled to the output of said second power supply and also coupled to the primary winding of said pulse transformer, said SCR being biased to conduct upon conduction of said unijunction transistor, thereby providing a signal to the primary winding of said pulse transformer.
Claim 8
Dependent Claim
24 words
The igniter circuit of claim 1 wherein the means for maintaining the ohmic contact of said unijunction transistor above ground potential is a resistor.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-16 | 1977-01-15 | 1977-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-16 | 1981-01-15 | 1981-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-16 | 1985-01-15 | 1985-07-17 | $7700.00 | Window Closed / Lapsed |