US5862033A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Exciter circuit
Assignee: Unison Industries LLC
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Filing: 1997-02-13
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Granted: 1999-01-19
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Expires: 2017-02-13
Abstract
Abstract An ignition system exciter circuit includes a storage capacitor; a charging circuit for charging the capacitor; a discharge circuit connectable to an igniter plug; and a first switching circuit for controlling discharge of the capacitor through the discharge circuit and plug; the discharge circuit comprising a step-up transformer for transforming voltage stored on the capacitor to a higher voltage across the igniter plug when the first switching circuit is closed; the transformer having a primary winding and a secondary winding, with the secondary winding having a first terminal that can be coupled to a first terminal of the igniter plug and a second terminal that can be coupled to a second terminal of the igniter plug; and a second switching circuit that is responsive to a voltage transition across the igniter plug and that prevents the transformer primary and secondary windings from conducting spark discharge current.
Inventors
- 👤 Dale F. Geislinger
- 👤 Howard V. Bonavia
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:24
CPC Classifications
F; F02; F02P; F02P15/00; F02P15/001; F02P15/003; F02P3/00; F02P3/06; F02P3/08; F02P3/09; F02P3/093
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
125 words
An ignition system exciter circuit comprising: a storage capacitor; a charging circuit for charging the capacitor; a discharge circuit connectable to an igniter plug; and a switching circuit for controlling discharge of the capacitor through the discharge circuit and plug; said discharge circuit comprising a step-up transformer having a primary winding and a secondary winding; said secondary winding having a first terminal that can be coupled to a first terminal of the igniter plug and a second terminal that can be coupled to a second terminal of the igniter plug; said primary winding having a first terminal that receives energy from the capacitor by operation of the switching circuit; and a rectifier connected between said primary winding first terminal and said secondary winding first terminal.
Claim 2
Dependent Claim
125 words
An ignition system exciter circuit comprising: a storage capacitor; a charging circuit for charging the capacitor; a discharge circuit connectable to an igniter plug; and a switching circuit for controlling discharge of the capacitor through the discharge circuit and plug; said discharge circuit comprising a step-up transformer having a primary winding and a secondary winding; said secondary winding having a first terminal that can be coupled to a first terminal of the igniter plug and a second terminal that can be coupled to a second terminal of the igniter plug; said primary winding having a first terminal that receives energy from the capacitor by operation of the switching circuit; and a rectifier connected between said primary winding first terminal and said secondary winding first terminal.
Claim 3
Dependent Claim
17 words
The apparatus of claim 1 comprising an impedance circuit coupled in series with said transformer primary winding.
Claim 4
Dependent Claim
12 words
The apparatus of claim 2 wherein said impedance circuit comprises a capacitor.
Claim 5
Dependent Claim
21 words
The apparatus of claim 1 wherein said rectifier prevents spark discharge current from flowing through said transformer primary and secondary windings.
Claim 6
Dependent Claim
28 words
The apparatus of claim 1 comprising an inductor having a first terminal connected to said switching circuit and a second terminal connected to said primary winding first terminal.
Claim 7
Dependent Claim
13 words
The apparatus of claim 5 wherein said inductor comprises an air core inductor.
Claim 8
Dependent Claim
12 words
The apparatus of claim 1 wherein said transformer comprises a pulse transformer.
Claim 9
Dependent Claim
38 words
The apparatus of claim 7 wherein said pulse transformer comprises a core which magnetically couples said primary and secondary windings, wherein said core is unsaturated throughout a time period during which the capacitor discharges through the igniter plug.
Claim 10
Dependent Claim
19 words
The apparatus of claim 1 wherein the igniter plug comprises an air gap plug or a semiconductor spark plug.
Claim 11
Dependent Claim
16 words
The apparatus of claim 1 wherein the ignition system is used in a gas turbine engine.
Claim 12
Dependent Claim
11 words
The apparatus of claim 1 wherein said rectifier comprises a diode.
Claim 13
Dependent Claim
17 words
The apparatus of claim 11 wherein said rectifier comprises a string of series or parallel connected diodes.
Claim 14
Dependent Claim
125 words
An ignition system exciter circuit comprising: an energy storage capacitor; a charging circuit for charging the capacitor; a discharge circuit connectable to an igniter plug; and a first switching circuit for controlling discharge of the capacitor through the discharge circuit and plug; said discharge circuit comprising a step-up transformer having a primary winding and a secondary winding; said secondary winding having a first terminal that is connectable to a first terminal of the igniter plug and a second terminal connectable to a second terminal of the igniter plug; said primary winding having a first terminal that receives energy from the capacitor by operation of the switching circuit; and a second switching circuit connected between said primary winding first terminal and said secondary winding first terminal.
Claim 15
Dependent Claim
125 words
An ignition system exciter circuit comprising: an energy storage capacitor; a charging circuit for charging the capacitor; a discharge circuit connectable to an igniter plug; and a first switching circuit for controlling discharge of the capacitor through the discharge circuit and plug; said discharge circuit comprising a step-up transformer having a primary winding and a secondary winding; said secondary winding having a first terminal that is connectable to a first terminal of the igniter plug and a second terminal connectable to a second terminal of the igniter plug; said primary winding having a first terminal that receives energy from the capacitor by operation of the switching circuit; and a second switching circuit connected between said primary winding first terminal and said secondary winding first terminal.
Claim 16
Dependent Claim
13 words
The apparatus of claim 13 wherein said second switching circuit comprises a diode.
Claim 17
Dependent Claim
12 words
The apparatus of claim 13 wherein said transformer comprises a pulse transformer.
Claim 18
Dependent Claim
38 words
The apparatus of claim 15 wherein said pulse transformer comprises a core which magnetically couples said primary and secondary windings, wherein said core is unsaturated throughout a time period during which the capacitor discharges through the igniter plug.
Claim 19
Dependent Claim
50 words
The apparatus of claim 13 wherein said second switching circuit produces substantially an open circuit between said primary winding first terminal and said secondary winding first terminal prior to a spark discharge at the igniter plug, and produces substantially a short circuit therebetween when the igniter plug begins to discharge.
Claim 20
Dependent Claim
146 words
An ignition system exciter circuit comprising: a storage capacitor; a charging circuit for charging the capacitor; a discharge circuit connectable to an igniter plug; and a first switching circuit for controlling discharge of the capacitor through the discharge circuit and plug; said discharge circuit comprising a step-up transformer for transforming voltage stored on the capacitor to a higher voltage across the igniter plug when the first switching circuit is closed; said transformer having a primary winding and a secondary winding, with said secondary winding having a first terminal that can be coupled to a first terminal of the igniter plug and a second terminal that can be coupled to a second terminal of the igniter plug; and a second switching circuit that is responsive to a voltage transition across the igniter plug and that prevents said transformer primary and secondary windings from conducting spark discharge current.
Claim 21
Dependent Claim
146 words
An ignition system exciter circuit comprising: a storage capacitor; a charging circuit for charging the capacitor; a discharge circuit connectable to an igniter plug; and a first switching circuit for controlling discharge of the capacitor through the discharge circuit and plug; said discharge circuit comprising a step-up transformer for transforming voltage stored on the capacitor to a higher voltage across the igniter plug when the first switching circuit is closed; said transformer having a primary winding and a secondary winding, with said secondary winding having a first terminal that can be coupled to a first terminal of the igniter plug and a second terminal that can be coupled to a second terminal of the igniter plug; and a second switching circuit that is responsive to a voltage transition across the igniter plug and that prevents said transformer primary and secondary windings from conducting spark discharge current.
Claim 22
Dependent Claim
39 words
The apparatus of claim 18 wherein said second switching circuit provides a very low impedance spark discharge current path from the capacitor to the plug to remove said transformer primary and secondary windings from said spark current discharge path.
Claim 23
Dependent Claim
51 words
The apparatus of claim 18 wherein said second switching circuit comprises a rectifier which completely removes said transformer primary and secondary windings from the discharge circuit operation after the igniter plug begins to conduct spark discharge current to prevent spark discharge current from passing through said transformer primary and secondary windings.
Claim 24
Dependent Claim
29 words
The apparatus of claim 18 wherein said voltage transition is characterized by a substantial voltage drop across the igniter plug when the plug begins to conduct spark discharge current.
Claim 25
Dependent Claim
35 words
The apparatus of claim 21 wherein said second switching circuit comprises a diode that changes from a reverse bias condition to a forward bias condition in response to said voltage transition across the igniter plug.
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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) | 2002-01-18 | 2002-07-20 | 2003-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-01-18 | 2006-07-20 | 2007-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-01-18 | 2010-07-20 | 2011-01-19 | $7700.00 | Window Closed / Lapsed |