Spark-ignited direct-injection engine combustion systems

Patent metadata

Field	Value
Publication number	US-10718258-B2
Application number	US-201615355343-A
Country	US
Kind code	B2
Filing date	Nov 18, 2016
Priority date	Nov 18, 2016
Publication date	Jul 21, 2020
Grant date	Jul 21, 2020

Abstract

A direct-injection stratified charge internal combustion engine includes a combustion cylinder to receive an air-fuel mixture, and an air intake port to inlet air into the combustion cylinder. The direct-injection engine also includes a fuel injector configured to deliver fuel within the cylinder in a spray pattern substantially aligned to a cylinder central axis to create the air-fuel mixture. A spark igniter is located within a path of the spray pattern to ignite combustion of the air-fuel mixture. The direct-injection engine further includes a movable piston defining a lower boundary of the combustion cylinder to contain the combustion of the air-fuel mixture. The piston is configured to include a bowl portion having local geometric features located on an intake port side of the combustion cylinder to redirect fluid flow towards a vortex in fluid communication with a combustion location near the cylinder central axis.

First claim

What is claimed is:

1. A direct-injection stratified charge internal combustion engine comprising:
a combustion cylinder configured to receive an air-fuel mixture;
intake ports configured to inlet air into the combustion cylinder;
exhaust ports configured to outlet exhaust from the combustion cylinder;
a fuel injector configured to deliver fuel within the combustion cylinder in a spray pattern substantially aligned to a cylinder central axis to create the air-fuel mixture;
wherein the fuel injector includes a tip that is centrally located within the combustion cylinder, and the tip is configured to spray the fuel in the spray pattern;
wherein the fuel injector is centrally located between the intake ports and the exhaust ports;
a spark igniter is located within a path of the spray pattern such that a trailing edge of the spray pattern when the spray pattern is initially ejected from the tip is ignited to combustion of the air-fuel mixture;
wherein a plane intersects the cylinder central axis, the fuel injector and the spark igniter such that the spark igniter aligns with the cylinder central axis and is offset from the fuel injector;
wherein the intake ports are disposed along the combustion cylinder relative to a first side of the plane to define an intake port side of the combustion cylinder;
wherein the exhaust ports are disposed along the combustion cylinder relative to a second side of the plane to define an exhaust port side of the combustion cylinder;
wherein the first and second sides of the plane oppose each other;
a movable piston defining a lower boundary of the combustion cylinder to contain the combustion of the air-fuel mixture, wherein the movable piston includes a bowl portion having an angled re-entrant edge located only on the intake port side to redirect fluid flow towards a vortex in fluid communication with a combustion location near the cylinder central axis;
wherein the movable piston includes a wall defining an outer side boundary of the bowl portion;
wherein the movable piston includes a plurality of raised portions spaced from each other to define a plurality of cutouts between the respective raised portions; and
wherein the raised portions surround the bowl portion, and the raised portions protrude outwardly farther from the bowl portion than the wall.

2. The direct-injection engine of claim 1 wherein the bowl portion is asymmetric relative to the cylinder central axis, and wherein the bowl portion defines a first opening edge on the intake port side that extends farther towards an outer edge of the movable piston relative to an opposing second opening edge on the exhaust port side.

3. The direct-injection engine of claim 2 wherein the bowl portion defines a radius r1 relative to the cylinder central axis and the first opening edge is extended by Δr, wherein 0.15*r1≤Δr≤0.35*r1.

4. The direct-injection engine of claim 1 wherein the bowl portion defines a first depth on the intake port side that is deeper than a second depth on the exhaust port side.

5. The direct-injection engine of claim 1 wherein the angled re-entrant edge is oriented at an angle α relative to the cylinder central axis to direct the air-fuel mixture back toward a center of the bowl portion, and 20 degrees≤α≤40 degrees.

6. The direct-injection engine of claim 1 wherein the movable piston further includes an extension wall extending from a top surface of the movable piston near an outer edge of the bowl portion.

7. The direct-injection engine of claim 6 wherein the extension wall is located on the intake port side.

8. A movable piston arranged to travel within a combustion chamber of a direct-injection engine according to a combustion cycle, the movable piston comprising:
a side portion configured to seal against a side of the combustion chamber;
a top surface defining a lower boundary of the combustion chamber to contain an air-fuel mixture during the combustion cycle;
a piston bowl formed in the top surface to receive a fuel injection dispensed at a location generally along a central cylinder axis, wherein the piston bowl defines a floor portion that extends in a first direction laterally towards the side portion from the central cylinder axis a distance that is greater than an opposing second direction from the central cylinder axis; and
wherein:
the top surface defines a plurality of cutouts spaced from each other, and each of the cutouts surround the piston bowl and intersect the side portion;
the floor portion extends a deeper depth on one side of the central cylinder axis that defines an intake port side than an opposing side of the central cylinder axis that defines an exhaust port side;
the piston bowl includes a side wall extending from the floor portion toward the top surface on the intake port side;
the piston bowl includes an angled re-entrant edge only on the intake port side;
the top surface includes an extension wall that extends outwardly away from the piston bowl along the intake port side, and the extension wall is offset from the side wall; and
the top surface includes a step disposed between and orientated transverse to the side wall and the extension wall to offset the extension wall from the side wall.

9. The movable piston of claim 8 wherein the first direction from the central cylinder axis is oriented on the intake port side.

10. The movable piston of claim 8 wherein the extension wall increases a height of the piston bowl on the intake port side.

11. The movable piston of claim 8 wherein the angled re-entrant edge redirects fluid flow towards a vortex in fluid communication with a combustion location near the central cylinder axis.

12. The movable piston of claim 11 wherein the angled re-entrant edge is oriented at an angle α relative to the central cylinder axis, and 20 degrees≤α≤40 degrees.

13. A direct-injection stratified charge internal combustion engine comprising:
a combustion cylinder configured to receive an air-fuel mixture;
intake ports configured to inlet air into the combustion cylinder;
exhaust ports configured to outlet exhaust from the combustion cylinder;
a fuel injector configured to emit a fuel spray pattern within the combustion cylinder at a location substantially near a cylinder central axis to create the air-fuel mixture;
wherein the fuel injector includes a tip that is centrally located within the combustion cylinder, and the tip is configured to spray the fuel spray pattern;
wherein the fuel injector is centrally located between the intake ports and the exhaust ports;
a spark igniter is located within a path of the fuel spray pattern such that a trailing edge of the fuel spray pattern when the fuel spray pattern is initially ejected from the tip is ignited to combustion of the air-fuel mixture;
wherein a plane intersects the cylinder central axis, the fuel injector and the spark igniter such that the spark igniter aligns with the cylinder central axis and is offset from the fuel injector;
wherein the intake ports are disposed along the combustion cylinder relative to a first side of the plane to define an intake port side of the combustion cylinder;
wherein the exhaust ports are disposed along the combustion cylinder relative to a second side of the plane to define an exhaust port side of the combustion cylinder;
wherein the first and second sides of the plane oppose each other;
a movable piston includes a top surface defining a lower boundary of the combustion cylinder that contains the combustion of the air-fuel mixture;
wherein the movable piston includes a side portion configured to seal against a side of a combustion chamber and includes a piston bowl def

Assignees

• Gm Global Tech Operations Llc

Inventors

• Solomon Arun S
• Spruit William F
• Sczomak David P

Classifications

• Y02T10/12

  Improving ICE efficiencies · CPC title

• F02F1/18

  Other cylinders · CPC title

• F02B23/101 Primary

  the injector being placed on or close to the cylinder centre axis, e.g. with mixture formation using spray guided concepts · CPC title

• F02F3/26

  having combustion chamber in piston head (the surface thereof being covered F02F3/14) · CPC title

• F02F3/00 Primary

  Pistons · CPC title