Spark plug configurations for dedicated-EGR engines

Patent metadata

Field	Value
Publication number	US-11519348-B2
Application number	US-201916675600-A
Country	US
Kind code	B2
Filing date	Nov 6, 2019
Priority date	Jun 2, 2017
Publication date	Dec 6, 2022
Grant date	Dec 6, 2022

Abstract

One embodiment is a system comprising an internal combustion engine having one or more non-dedicated cylinders and one or more dedicated EGR cylinders configured to provide EGR to the engine via an EGR loop, a first spark plug coupled to each of the one or more non-dedicated cylinders, and a second spark plug coupled to each of the one or more dedicated EGR cylinders, wherein the second spark plug has a physical or dimensional characteristic that is different from the first spark plug. In certain forms each of the non-dedicated cylinders has only one of a first type of spark plug and each of the dedicated EGR cylinders has only one of a second type of spark plug. One or more of the characteristics that may vary between the first and second types of spark plugs include spark gap, electrode diameter, heat range, and ion sensing capability.

First claim

What is claimed is:

1. A system, comprising:
an internal combustion engine having one or more non-dedicated cylinders and one or more dedicated Exhaust Gas Recirculation (EGR) cylinders configured to provide EGR to the engine via an EGR loop;
one or more first spark plugs coupled to each of the one or more non-dedicated cylinders, the first spark plugs including first physical characteristics;
one or more second spark plugs coupled to each of the one or more dedicated EGR cylinders, the second spark plugs including second physical characteristics, wherein the second physical characteristics differ from the first physical characteristics effective to provide different spark plug geometries of the second spark plugs relative to the first spark plugs, wherein the different spark plug geometries include the first spark plug has a first electrode diameter and the second spark plug has a second electrode diameter that is smaller than the first electrode diameter, and further wherein the different spark plug geometries include the first spark plug has a first tip protrusion into the non-dedicated cylinder, the second spark plug has a second tip protrusion into the dedicated EGR cylinder that is greater than the first tip protrusion such that the first tip protrusion into the non-dedicated cylinder is less than the second tip protrusion; and
an electronic control system operatively coupled to the one or more non-dedicated cylinders and the one or more dedicated EGR cylinders, the electronic control system is structured to execute control operations to control fueling of the one or more dedicated EGR cylinders and to control fueling of the one or more non-dedicated cylinders independently from the one or more dedicated EGR cylinders,
wherein the electronic control system is configured to control the one or more non-dedicated cylinders in a first combustion mode, and the electronic control system is configured to control the one or more dedicated EGR cylinders in a second combustion mode.

2. The system of claim 1 , wherein each of the one or more non-dedicated cylinders has only one of the first spark plugs, and each of the one or more dedicated EGR cylinders has only one of the second spark plugs.

3. The system of claim 1 , wherein the first combustion mode is stoichiometric, and the second combustion mode is rich.

4. The system of claim 1 , wherein the different spark plug geometries include the first spark plug has a first spark gap and the second spark plug has a second spark gap that is greater than the first spark gap.

5. The system of claim 1 , wherein only the first spark plugs are operatively coupled with the one or more non-dedicated cylinders and only the second spark plugs are operatively coupled with the one or more dedicated cylinders.

6. The system of claim 1 , wherein the internal combustion engine is a six cylinder engine wherein two cylinders are dedicated EGR cylinders.

7. The system of claim 1 , wherein the different spark plug geometries include the first spark plug has a first heat range and the second spark plug has a second heat range that is greater than the first heat range.

8. A system, comprising:
an internal combustion engine having one or more non-dedicated cylinders and one or more dedicated Exhaust Gas Recirculation (EGR) cylinders configured to provide EGR to the engine via an EGR loop, wherein each of the one or more non-dedicated cylinders has only one of a first spark plug, the first spark plug is configured to perform a first spark to a first temperature range, and wherein each of the one or more dedicated EGR cylinders has only one of a second spark plug, the second spark plug is configured to perform a second spark to a second temperature range wherein the second temperature range is higher than the first temperature range, wherein the first spark plug has a first tip protrusion into the non-dedicated cylinder, the second spark plug has a second tip protrusion into the dedicated EGR cylinder that is greater than the first tip protrusion such that the first tip protrusion into the non-dedicated cylinder is less than the second tip protrusion; and
an electronic control system operatively coupled to the one or more non-dedicated cylinders and the one or more dedicated EGR cylinders, the electronic control system is structured to execute control operations to control fueling of the one or more dedicated EGR cylinders and to control fueling of the one or more non-dedicated cylinders independently from the one or more dedicated EGR cylinders, the electronic control system is configured to control the one or more non-dedicated cylinders in a first combustion mode, and the electronic control system is configured to control the one or more dedicated EGR cylinders in a second combustion mode.

9. The system of claim 8 , wherein the second spark plug has a physical or dimensional characteristic that is different from the first spark plug, wherein the second physical characteristic differs from the first physical characteristic effective to provide a different spark plug geometry of the second spark plug relative to the first spark plug.

10. The system of claim 9 , wherein the different spark plug geometry includes the first spark plug has a first spark gap, and the second spark plug has a second spark gap that is greater than the first spark gap.

11. The system of claim 9 , wherein the different spark plug geometry includes the first spark plug has a first heat range and the second spark plug has a second heat range that is higher than the first heat range.

12. The system of claim 9 , wherein the different spark plug geometry includes the first spark plug has a first electrode diameter and the second spark plug has a second electrode diameter that is smaller than the first electrode diameter.

13. The system of claim 8 , wherein the first combustion mode is stoichiometric, and the second combustion mode is stoichiometric.

14. A method of operating an internal combustion engine, the method comprising:
providing a dedicated Exhaust Gas Recirculation (EGR) engine having one or more non-dedicated cylinders and one or more dedicated EGR cylinders, each of the one or more non-dedicated cylinders having only a first spark plug, the first spark plug having first physical characteristics, and each of the one or more dedicated EGR cylinders having only a second spark plug, the second spark plug including second physical characteristics, wherein the second physical characteristics differ from the first physical characteristics effective to provide different spark plug geometries of the second spark plug relative to the first spark plug, wherein the different spark plug geometries include the first spark plug has a first tip protrusion into the non-dedicated cylinder, the second spark plug has a second tip protrusion into the dedicated EGR cylinder that is greater than the first tip protrusion such that the first tip protrusion into the non-dedicated cylinder is less than the second tip protrusion;
providing an electronic control system operatively coupled to the one or more non-dedicated cylinders and the one or more dedicated EGR cylinders;
controlling with the electronic control system fueling of the one or more dedicated EGR cylinders and controlling fueling of the one or more non-dedicated cylinders independently from the one or more dedicated EGR cylinders; and
controlling with the electronic control system the one or more non-dedicated cylinders in a first combustion mode and the one or more dedicated EGR cylinders in a second combustion mode.

15. The method of claim 14 , wherein the first combustion mode is stoi

Assignees

• Cummins Inc

Inventors

• Kolhouse J Steven
• Stroh David J
• O'Connor Daniel J

Classifications

• F02P5/1512

  with particular means concerning an individual cylinder · CPC title

• F02D2200/0406

  Intake manifold pressure · CPC title

• F02D41/1448

  the characteristics being an exhaust gas pressure · CPC title

• F02D35/021

  using an ionic current sensor · CPC title

• F02D2200/0414

  Air temperature · CPC title