Engine system and a method of operating a direct injection engine

Patent metadata

Field	Value
Publication number	US-9441569-B2
Application number	US-201313893150-A
Country	US
Kind code	B2
Filing date	May 13, 2013
Priority date	May 21, 2012
Publication date	Sep 13, 2016
Grant date	Sep 13, 2016

Abstract

Systems and methods are provided for an engine. The system comprises a direct injection engine having a cylinder in which a piston is slidingly supported to form in combination with a cylinder head a combustion chamber; a fuel injector for the cylinder having a catalytic coated tip portion that projects into the combustion chamber; and an electronic controller to control the operation of the engine and operates the engine in a heating mode of operation if heating of the fuel injector tip is requested. Various methods for heating the fuel injector tip are proposed including operating the engine on a reduced number of cylinders and varying one or both of fuel injection timing and quantity of fuel injected and the ignition timing in order to increase the temperature of combustion.

First claim

The invention claimed is:

1. An engine system comprising:
a direct injection engine having at least one cylinder in which a piston is slidingly supported to form in combination with a cylinder head at least one combustion chamber;
a fuel injector for the at least one cylinder having a fuel injector tip with a catalytic coated portion that projects into the combustion chamber; and
an electronic controller with code to be programmed into non-transitory memory of a computer readable storage medium in the controller to control the operation of the engine and operate the engine in a heating mode of operation if heating of the fuel injector tip is requested, wherein the code to operate the engine in the heating mode further comprises code to disable each of the cylinders of the engine, one at a time in an order, so as to increase loading on each cylinder still operating and cool the disabled cylinder until the catalytic coating on the respective fuel injector tip of the operating cylinder is heated to a light-off temperature of the catalytic coating.

2. The engine system as claimed in claim 1 wherein if heating of the fuel injector tip is not requested, the electronic controller further includes code to operate the engine in a normal mode of operation.

3. The engine system as claimed in claim 1 wherein heating of the fuel injector tip is requested if a temperature of the catalytic coated portion is below light-off temperature of the catalytic coating.

4. The engine system as claimed in claim 3 wherein heating of the fuel injector tip is requested if the temperature of the catalytic coated portion is below the light-off temperature of the catalytic coating and de-coking of the fuel injector tip is requested.

5. The engine system as claimed in claim 1 wherein the code to operate the engine in the heating mode further comprises code to increase a temperature of combustion to adjust at least one of a timing of an injection of fuel and a quantity of fuel injected into the combustion chamber.

6. The engine system as claimed in claim 4 wherein the request to de-coke the fuel injector tip is based upon an accretion model.

7. The engine system as claimed in claim 1 wherein each disabled cylinder is arranged to pump air while it is disabled.

8. The engine as claimed in claim 1 wherein operating the engine in the heating mode comprises operating at least one cylinder rich of stoichiometric and at least one cylinder lean of stoichiometric so as to promote an increased combustion temperature and an oxidizing environment in the at least one lean operated cylinder.

9. The engine system as claimed in claim 1 wherein the engine is a spark ignited engine and code to operate the engine in the heating mode further includes code to increase a temperature of combustion of the operating cylinder by using the electronic controller to adjust a timing of an ignition to one of retarded and advanced relative to a normal timing position.

10. A method of operating a direct injection combustion engine, each cylinder of the engine having a fuel injector having a fuel injector tip with a catalytic coated portion that is exposed to products of combustion, comprising:
operating the engine in a heating mode of operation in response to a request to heat the fuel injector tip, the heating mode of operation including:
disabling each of the cylinders of the engine, one at a time in an order, so as to increase loading on cylinders still operating and cool the disabled cylinder, where the disabled cylinder remains disabled until the catalytic coating on the respective fuel injector tip of the operating cylinder is heated to a threshold.

11. The method as claimed in claim 10 wherein, if heating of the fuel injector tip is not requested, the method comprises operating the engine in a normal mode of operation.

12. The method as claimed in claim 10 wherein heating of the fuel injector tip is requested when a temperature of the catalytic coated portion is below a light-off temperature of a catalytic material and de-coking of the fuel injector tip is requested.

13. The method as claimed in claim 10 wherein operating the engine in the heating mode comprises adjusting at least one of a timing of an injection of fuel and a quantity of fuel injected into each operating cylinder.

14. The method as claimed in claim 12 wherein the request for de-coking of the fuel injector tip is based upon an accretion model.

15. The method as claimed in claim 10 wherein operating the engine in said heating mode comprises operating at least one cylinder rich of stoichiometric and at least one cylinder lean of stoichiometric so as to promote an increased combustion temperature and an oxidizing environment in the at least one lean operated cylinder.

16. The method as claimed in claim 10 wherein operating the engine in said heating mode comprises operating at least one cylinder lean of stoichiometric and at least one cylinder leaner than the at least one lean of stoichiometric operating cylinder so as to promote an increased combustion temperature in the at least one leaner operated cylinder.

17. The method as claimed in claim 10 wherein the engine is a spark ignited engine and operating the engine in the heating mode comprises adjusting a timing of an ignition to one of retarded and advanced relative to a normal timing position for each operating cylinder.

18. The method as claimed in claim 10 wherein disabling at least one of the cylinders of the engine comprises disabling fuel injection to the at least one disabled cylinder of the engine and where a predetermined number of cylinders are coupled through an exhaust manifold to a first catalytic converter and the remaining cylinders are coupled to another exhaust manifold to a second catalytic converter.

19. The method as claimed in claim 18 wherein said predetermined number of cylinders comprises one bank of a V-6 engine and said remaining cylinders comprise another bank of said V-6 engine.

20. The method as claimed in claim 18 wherein said predetermined number of cylinders comprises two outer cylinders of an I-4 engine and said remaining cylinders comprise two inner cylinders of said I-4 engine.

Assignees

• Ford Global Tech Llc

Inventors

• Skipp David
• Hoare Graham
• Berkemeier Oliver
• Crisp Nicholas Dashwood

Classifications

• F01N13/107

  More than one exhaust manifold or exhaust collector · CPC title

• F02P5/151

  with means for compensating the variation of the characteristics of the engine or of a sensor, e.g. by ageing · CPC title

• F02D41/40

  with means for controlling injection timing or duration · CPC title

• F02M61/1893

  Details of valve member ends not covered by groups F02M61/1866 - F02M61/188 · CPC title

• F02D41/3005 Primary

  Details not otherwise provided for · CPC title