CORONA IGNITION SYSTEM HAVING SELECTIVE ENHANCED ARC FORMATION

• US 20120180742A1
• Filed: 01/13/2012
• Published: 07/19/2012
• Est. Priority Date: 01/13/2011
• Status: Active Grant

• Current Assignee: Federal-Mogul Ignition LLC (Apollo Global Management, Inc.)
• Original Assignee: Federal-Mogul Ignition Company (Apollo Global Management, Inc.)
• Inventors: Burrows, John Antony
• Granted Patent: US 8,726,871 B2
• Time in Patent Office: Days
• US Class Current: 123/143.B
• CPC Class Codes: F02P 15/10 having continuous electric sparks
• CPC Class Codes: F02P 23/04 Other physical ignition means, e.g. using laser rays
• CPC Class Codes: F02P 23/045 using electromagnetic microwaves
• CPC Class Codes: F02P 3/01 Electric spark ignition installations without subsequent energy storage, i.e. energy supplied by an electrical oscillator with magneto- or dynamo-electric generators F02P1/00; piezoelectric ignition F02P3/12; with continuous electric spark F02P15/10
• CPC Class Codes: F02P 3/0807 Closing the discharge circuit of the storage capacitor with electronic switching means F02P3/0853, F02P3/0876, F02P3/09 take precedence
• CPC Class Codes: F02P 9/007 by supplementary electrical discharge in the pre-ionised electrode interspace of the sparking plug, e.g. plasma jet ignition
• CPC Class Codes: H01T 13/50 having means for ionisation of gap H01T13/52 takes precedence

Abstract

A corona discharge (24) ignition includes an electrode (38) emitting a radio frequency electric field and providing a corona discharge (24) to ignite a combustible mixture. The system includes a controlled high voltage energy supply (52) providing energy to a main energy storage (28) at a main voltage. A fixed high voltage energy supply (54) provides extra energy to an extra energy storage (26) at an extra voltage, which is greater than the main voltage. While the corona discharge (24) is being provided, the energy of the main energy storage (28), but not the extra energy storage (26), is provided to the electrode (38). When the corona discharge (24) switches to arc discharge, the extra energy of the extra energy storage (26) is provided to the corona igniter (22) to enhance the arc discharge and provide reliable ignition until the corona discharge (24) is restored.

Claims

1. A corona discharge (24) ignition system for igniting a combustible mixture of fuel and air in a combustion chamber (20), comprising:

an electrode (38) for receiving energy at a radio frequency voltage and emitting a radio frequency electric field to ionize the combustible mixture and provide a corona discharge (24) igniting said combustible mixture,

a main energy storage (28) storing energy at a main voltage and providing the energy ultimately to said electrode (38), and

an extra energy storage (26) storing energy at an extra voltage being greater than said main voltage and providing the energy ultimately to said electrode (38) only when arc discharge occurs to enhance said arc discharge.

2. The system of claim 1 including a switch (72) between said extra energy storage (26) and said electrode (38) to prevent the energy of said extra energy storage (26) from being provided to said electrode (38) while said corona discharge (24) is provided.

3. The system of claim 2 including a switch control (74) instructing said switch (72) to remain open when said corona discharge (24) is provided and to close when said arc discharge occurs, wherein said closed switch (72) allows the energy of said extra energy storage (26) to be provided to said electrode (38).

4. The system of claim 1 wherein said extra voltage is at least 1.1 times greater than said main voltage.

5. The system of claim 1 including a power supply (42) and a controlled high voltage energy supply (52) providing the energy from said power supply (42) to said main energy storage (28) at said main voltage and a fixed high voltage energy supply (54) separate from said controlled high voltage energy supply (52) providing the energy from said power supply (42) to said extra energy storage (26) at said extra voltage.

6. The system of claim 5 wherein said fixed high voltage energy supply (54) maintains said extra energy storage (26) fully charged.

7. The system of claim 1 wherein said main voltage provided by said controlled high voltage energy supply (52) is 10 V to 100 V and said extra voltage provided by said fixed high voltage supply is 100 to 200 V.

8. The system of claim 1 including an igniter drive circuit (46) and a igniter driver (48), wherein

said igniter drive circuit (46) transmits corona drive signals (56) to said igniter driver (48), said corona drive signals (56) indicate a predetermined time, duration, voltage level, and resonant frequency of the energy ultimately provided to said electrode (38),

said igniter driver (48) receives said corona drive signals (56) and the energy from said main energy storage (28) and provides the energy at the predetermined time, duration, voltage level, and resonant frequency ultimately to said electrode (38).

9. The system of claim 8 including an LC circuit (64) receiving the energy from said igniter driver (48) and increasing the voltage and decreasing the current prior to providing the energy to said electrode (38).

10. The system of claim 8 wherein said igniter drive circuit (46) is an oscillating circuit operating at a high frequency of 0.5 to 2.0 MHz.

11. A method for igniting a combustible mixture of fuel and air in a combustion chamber (20), comprising the steps of:

storing energy in a main energy storage (28) at a main voltage,

providing the energy from the main energy storage (28) ultimately to an electrode (38) allowing the electrode (38) to emit a radio frequency electric field to ionize the combustible mixture and provide a corona discharge (24) igniting the combustible mixture,

storing energy in an extra energy storage (26) at an extra voltage being greater than the main voltage, and

providing the energy from the extra energy storage (26) to the electrode (38) only when arc discharge occurs to enhance the arc discharge.

12. The method of claim 11 including preventing the energy of the extra energy storage (26) from being provided to the electrode (38) while the corona discharge (24) is being provided.

13. The method of claim 11 including maintaining the extra energy storage (26) fully charged.

14. The method of claim 11 including supplying the energy to the main energy storage (28) at a main current and supplying the energy to the extra storage at an extra current greater than the main current.