Diesel engine

Patent metadata

Field	Value
Publication number	US-2025020088-A1
Application number	US-202218717543-A
Country	US
Kind code	A1
Filing date	Aug 29, 2022
Priority date	Dec 10, 2021
Publication date	Jan 16, 2025
Grant date	—

Abstract

A diesel engine 1 includes: an injector 15 ; a control device which controls an injection timing of fuel 81 injected from the injector 15 ; and exhaust circulating means. The control device controls the injection timing of main injection and pre-injection performed prior to the main injection and executes control such that, by ensuring a premixing period of the pre-injection from start of the pre-injection until ignition of an air-fuel mixture of the fuel 81 injected by the pre-injection and the air AR, a homogenous and lean premixed air-fuel mixture is generated in the auxiliary combustion chamber 13 by the fuel 81 injected by the pre-injection and air AR, and the premixing period of the main injection from the start of the main injection until ignition of the air-fuel mixture of the fuel 81 injected by the main injection and the air AR is ensured.

First claim

1 . A diesel engine having a main combustion chamber and an auxiliary combustion chamber communicating with the main combustion chamber, the diesel engine comprising:
an injector that is provided facing the auxiliary combustion chamber and injects fuel into the auxiliary combustion chamber; a control device that controls an injection timing of the fuel injected from the injector; and exhaust circulating means that circulates exhaust of an engine wherein, the control device controls the injection timing of main injection and pre-injection performed prior to the main injection and executes control such that, by ensuring a premixing period of the pre-injection from start of the pre-injection until ignition of an air-fuel mixture of the fuel injected by the pre-injection and air, a homogenous and lean premixed air-fuel mixture is generated in the auxiliary combustion chamber by the fuel injected by the pre-injection and the air, and the premixing period of the main injection from the start of the main injection until ignition of the air-fuel mixture of the fuel injected by the main injection and the air is ensured.

2 . The diesel engine according to claim 1 , wherein
the injection timing of the main injection is a timing after a peak of a heat generation rate generated by the pre-injection and before a top dead center in a compression stroke.

3 . The diesel engine according to claim 2 , wherein
a timing of ignition of the air-fuel mixture of the fuel injected by the main injection and the air is at the top dead center and after the top dead center in the compression stroke.

4 . The diesel engine according to claim 2 , wherein
the injection timing of the pre-injection is a timing at which a crank angle is 60° or more and 120° or less before the top dead center in the compression stroke.

5 . The diesel engine according to claim 2 , wherein
the injection timing of the pre-injection is a timing at which a crank angle is 80° or more and 120° or less before the top dead center in the compression stroke.

6 . The diesel engine according to claim 1 , wherein
the control device executes the pre-injection prior to the main injection only once.

7 . The diesel engine according to claim 1 , wherein
the pre-injection is pilot injection.

8 . The diesel engine according to claim 3 , wherein
the injection timing of the pre-injection is a timing at which a crank angle is 60° or more and 120° or less before the top dead center in the compression stroke.

9 . The diesel engine according to claim 3 , wherein
the injection timing of the pre-injection is a timing at which a crank angle is 80° or more and 120° or less before the top dead center in the compression stroke.

Assignees

• Kubota Kk

Inventors

• Kobayashi Yasushi
• Nagai Naotaro
• Kaneko Rina
• Tennomi Masanari
• Matsuo Naruhiro

Classifications

• F02B19/08

  the chamber being of air-swirl type · CPC title

• F02B3/06

  with compression ignition (compression ignition engines using air or gas for blowing fuel into compressed air in cylinder F02B13/02) · CPC title

• F02B1/12

  with compression ignition (with fuel-air charge ignited by compression ignition of an additional fuel F02B7/00) · CPC title

• F02D41/402

  Multiple injections · CPC title

• F02D41/405

  with post injections · CPC title