Capacitor discharge ignition system

• US 4,027,198 A
• Filed: 08/14/1975
• Issued: 05/31/1977
• Est. Priority Date: 08/14/1975
• Status: Expired due to Term

• Current Assignee: Unison Industries Limited Partnership A de Limited Partnership
• Original Assignee: The Bendix Corporation (Honeywell International Inc.)
• Inventors: Linkroum, Irving E.
• Primary Examiner(s): Chatmon, Jr., Saxfield
• Application Number:
  US05/604,687
• Time in Patent Office: 656 Days
• Field of Search: 315/209 CD, 315/209 SC, 315/241 R, 315/227 R, 315/276, 315/277, 315/278, 315/247, 315/279, 123/148
• US Class Current: 315/209.0CD
• CPC Class Codes: F02P 1/086 for generating sparks by discharging a capacitor into a coil circuit
• CPC Class Codes: F02P 15/003 Layout of ignition circuits for gas turbine plants ignition of gas turbine plants per se F02C7/26

Abstract

A capacitor discharge ignition system for a jet engine which has a relatively high power factor at the transformer input without exceeding the one ampere current rating required in jet ignition systems at the desired power level. A specially designed power transformer (10 ) has a capacitor (3) connected across closely coupled primary and tertiary windings (11 and 12).

Claims

1. A capacitor discharge ignition system for igniting fuel in a jet engine comprising:

a transformer having a secondary winding, a primary winding for receiving alternating electric current, and a tertiary winding in series with the primary winding;

a first capacitor electrically connected across the primary and tertiary windings of said transformer;

a second capacitor;

means for rectifying the alternating electric current received from the secondary winding of said transformer and supplying such rectified current to the second capacitor; and

means for periodically discharging the electrical energy stored in said second capacitor, including;

a switching device periodically rendered electrically conductive and electrically nonconductive, said switching device permitting said second capacitor to discharge when conductive and preventing said second capacitor from discharging when electrically nonconducting;

a second transformer having a first winding and a second winding, with said first winding coupled to said switching device; and

a discharge device coupled in series with the second transformer for dissipating the electrical energy from said second capacitor when said switching device is rendered electrically conductive, said discharge device located within the jet engine for igniting fuel therein, whereby the discharge of the second capacitor through the switching device causes igniting of the fuel in the jet engine.

2. A capacitor discharge ignition system as recited in claim 1 wherein said means for periodically discharging the electrical energy stored in said second capacitor further includes:

a third capacitor; and

wherein said second winding of the second transformer and said third capacitor are connected in series with each other and across said switching device, and said first winding is electrically connected to receive the discharge from said second capacitor when said switching device is rendered conductive; and

wherein the discharge device is a spark plug having spaced electrodes electrically connected in series with said first winding, whereby when said switching device conducts said third capacitor discharges through the second winding of said second transformer causing an electrical discharge of energy to occur between the electrodes of said spark plug, allowing the second capacitor to discharge through the first winding of said second transformer and across the electrodes of said spark plug.

6. The capacitor discharge ignition system as recited in claim 1 wherein the primary winding and the tertiary winding of said transformer have the same number of turns.

7. The capacitor discharge ignition system as recited in claim 2 wherein the primary winding and the tertiary winding of said transformer have the same number of turns.

3. An ignition system for periodically igniting fuel in a jet engine, said system comprising:

a transformer having a primary winding for receiving electrical energy, a tertiary winding in series with the primary winding and a secondary winding electromagnetically coupled to said primary and tertiary windings;

a capacitor connected across the primary and tertiary windings of said transformer;

means for storing electrical energy received from the secondary winding of said transformer; and

means for periodically discharging the electrical energy stored in the means for storing electrical energy, including

a switching device selectively rendered electrically conductive and electrically nonconductive, said switching device permitting said energy storage device to discharge its stored energy when conductive and preventing said energy storage device from discharging its stored energy when electrically nonconductive;

a second transformer having a primary winding and a secondary winding and coupled to said switching device; and

a discharge device coupled in series with the secondary winding for dissipating electrical energy from said second capacitor when said switching device is conductive, said discharge device located within the jet engine for igniting fuel therein, whereby said energy storing device periodically discharges its stored energy through the switching device to cause igniting of the fuel in the jet engine.

4. An ignition system as recited in claim 3 wherein said discharge device includes:

a spark plug having spaced electrodes, said spark plug adapted to receive and dissipate the energy discharged from said energy storage means across the spaced electrodes of said spark plug.

5. An ignition system as recited in claim 4 wherein said means for periodically discharging the electrical energy stored in the means for storing electrical energy includes:

means for periodically rendering said switching device electrically conductive and electrically nonconductive.

8. The capacitor discharge ignition system as recited in claim 3 wherein the primary winding and the tertiary winding of said transformer have the same number of turns.

9. The capacitor discharge ignition system as recited in claim 4 wherein the primary winding and the tertiary winding of said transformer have the same number of turns.