Engine system

Patent metadata

Field	Value
Publication number	US-11248520-B2
Application number	US-202016775530-A
Country	US
Kind code	B2
Filing date	Jan 29, 2020
Priority date	Apr 1, 2019
Publication date	Feb 15, 2022
Grant date	Feb 15, 2022

Abstract

An engine system capable of controlling an intake air flow includes a combustion chamber, an ignition plug, an intake air flow control valve, and a controller. The controller performs, in at least a part of an operating range, SPCCI combustion in which after jump-spark ignition combustion of a portion of a mixture gas inside the combustion chamber by a jump-spark ignition of the ignition plug, compression ignition combustion of the remaining mixture gas is carried out by a self-ignition. The controller strengthens, at least in a part of the operating range of SPCCI combustion, the intake air flow inside the combustion chamber by controlling the intake air flow control valve. The controller controls, in a middle-load range of the operating range where SPCCI combustion is performed, the intake air flow control valve so that the intake air flow becomes weaker than in a high-load range and a low-load range.

First claim

What is claimed is:

1. An engine system capable of controlling an intake air flow, comprising:
a combustion chamber;
an ignition plug disposed inside the combustion chamber;
an intake air flow control valve configured to generate an intake air flow inside the combustion chamber; and
a controller configured to control the ignition plug and the intake air flow control valve,
wherein the controller performs, in at least a part of an operating range, partial compression ignition combustion in which after jump-spark ignition combustion of a portion of a mixture gas inside the combustion chamber by a jump-spark ignition of the ignition plug, compression ignition combustion of the remaining mixture gas inside the combustion chamber is carried out by a self-ignition,
wherein the controller controls the intake air flow control valve at least in a part of the operating range of the partial compression ignition combustion, such that turbulence in the intake air flow inside the combustion chamber is increased and the intake air is swirled in the combustion chamber,
wherein the controller controls, in a given middle-load range, higher than a first predetermined load and lower than a second predetermined load higher than the first predetermined load, of the operating range where the partial compression ignition combustion is performed, an opening of the intake air flow control valve to be a first predetermined opening so that the intake air flow becomes weaker than in a high-load range, higher than the second predetermined load, where the load is higher than the middle-load range and a low-load range, lower than the first predetermined load, where the load is lower than the middle-load range,
wherein the controller controls, in the high-load range of the operating range, the opening of the intake air flow control valve to be a second predetermined opening smaller than the first predetermined opening so that the intake air flow becomes stronger than in the middle-load range, and
wherein the controller controls, in the low-load range of the operating range, the opening of the intake air flow control valve to be a third predetermined opening smaller than the first predetermined opening so that the intake air flow becomes stronger than in the middle-load range.

2. The engine system of claim 1 , wherein the intake air flow control valve is a swirl control valve configured to generate a swirl flow inside the combustion chamber.

3. The engine system of claim 1 , wherein the controller controls the ignition plug so that an ignition timing is retarded in the high-load range where the partial compression ignition combustion is performed.

4. The engine system of claim 1 , further comprising an intake valve configured to introduce intake air into the combustion chamber, and an exhaust valve configured to discharge exhaust gas after combustion inside the combustion chamber,
wherein the controller controls the intake valve and the exhaust valve, in the low-load range where the partial compression ignition combustion is performed, to increase an amount of internal exhaust gas recirculation.

5. The engine system of claim 1 , wherein the ignition plug is disposed in a circumferential part inside the combustion chamber.

6. The engine system of claim 5 , further comprising an intake valve configured to introduce intake air into the combustion chamber,
wherein the ignition plug is disposed in the circumferential part inside the combustion chamber on the side where the intake valve is provided.

7. The engine system of claim 1 , wherein the controller controls, in a middle engine speed range of the high-load range, the opening of the intake air flow control valve to be a fourth predetermined opening smaller than the first predetermined opening.

8. A method of controlling an intake air flow, comprising the steps of:
controlling an ignition plug disposed inside a combustion chamber and an intake air flow control valve configured to generate an intake air flow inside the combustion chamber to perform, in at least a part of an operating range, partial compression ignition combustion in which after jump-spark ignition combustion of a portion of a mixture gas inside the combustion chamber by a jump-spark ignition of the ignition plug, compression ignition combustion of the remaining mixture gas inside the combustion chamber is carried out by a self-ignition;
controlling the intake air flow control valve at least in a part of the operating range of the partial compression ignition combustion, such that turbulence in the intake air flow inside the combustion chamber is increased and the intake air is swirled in the combustion chamber;
controlling, in a given middle-load range of the operating range, higher than a first predetermined load and lower than a second predetermined load higher than the first predetermined load, where the partial compression ignition combustion is performed, an opening of the intake air flow control valve to be a first predetermined opening so that the intake air flow becomes weaker than in a high-load range, higher than the second predetermined load, where the load is higher than the middle-load range and a low-load range, lower than the first predetermined load, where the load is lower than the middle-load rang,
controlling, in the high-load range of the operating range, the opening of the intake air flow control valve to be a second predetermined opening smaller than the first predetermined opening so that the intake air flow becomes stronger than in the middle-load range, and
controlling, in the low-load range of the operating range, the opening of the intake air flow control valve to be a third predetermined opening smaller than the first predetermined opening so that the intake air flow becomes stronger than in the middle-load range.

9. The method of claim 8 , further comprising: controlling, in a middle engine speed range of the high-load range, the opening of the intake air flow control valve to be a fourth predetermined opening smaller than the first predetermined opening.

Assignees

• Mazda Motor

Inventors

• Inoue Atsushi
• Chikada Tetsuya
• Kawai Yusuke

Classifications

• F02B2023/108

  Swirl flow, i.e. the axis of rotation of the main charge flow motion is vertical · CPC title

• F02D2041/0015

  for engines with means for controlling swirl or tumble flow, e.g. by using swirl valves · CPC title

• F02D41/3041 Primary

  with means for triggering compression ignition, e.g. spark plug · CPC title

• F02M26/03

  with a single mechanically or electrically driven intake charge compressor · CPC title

• F02M35/10163

  having air intakes specially adapted to selectively deliver naturally aspirated fluid or supercharged fluid · CPC title