Combustion chamber of direct injection diesel engine for reducing the NOx

Patent metadata

Field	Value
Publication number	US-9284877-B2
Application number	US-201313971338-A
Country	US
Kind code	B2
Filing date	Aug 20, 2013
Priority date	Sep 14, 2012
Publication date	Mar 15, 2016
Grant date	Mar 15, 2016

Abstract

Disclosed is a combustion chamber of a diesel engine provided with a bowl having a concave shape so that fuel injected from an injector creates a swirl or squishing flow to be mixed with air, and the combustion chamber of the diesel engine includes: a pip protruding from a center of a lower surface of the bowl toward the injector; a lip part protruding from a side surface of the bowl toward the injector; and a main combustion chamber provided on a lower portion of the lip part and a sub combustion chamber provided on an upper portion of the lip part, with the lip part interposed therebetween, in which a surface of the sub combustion chamber is formed in a flat shape or a concave bowl shape to have a depth of the sub combustion chamber of 0.8 mm or lower.

First claim

What is claimed is:

1. A combustion chamber of a diesel engine provided with a bowl having a concave shape so that fuel injected from an injector is mixed with air, the combustion chamber comprising:
a pip protruding from a center of a lower surface of the bowl toward the injector;
a lip part protruding from a side surface of the bowl toward the injector; and
a main combustion chamber provided on a lower portion of the lip part and a sub combustion chamber provided on an upper portion of the lip part, with the lip part interposed therebetween,
wherein a surface of the sub combustion chamber is formed in a concave bowl shape optimized to reduce generation of nitrogen oxide by causing the fuel injected from the injector to swirl and squish by having a depth of the sub combustion chamber of 1.0 mm or lower.

2. The combustion chamber of claim 1 , wherein the depth of the sub combustion chamber is equal to or lower than 0.8 mm.

3. The combustion chamber of claim 2 , wherein the depth of the sub combustion chamber is 0.2 mm to 0.8 mm.

4. The combustion chamber of claim 1 , wherein a diameter of the lip part is smaller than a maximum diameter of the main combustion chamber, and the maximum diameter of the main combustion chamber is smaller than a diameter of an entrance of the combustion chamber.

5. The combustion chamber of claim 1 , wherein a ratio of a lip curvature center depth of the lip part to a combustion chamber maximum depth of the main combustion chamber is 2.2 to 2.8.

Assignees

• Doosan Infracore Co Ltd

Inventors

• Yoo Doc Koon
• Kim Chung Min
• Ahn Jong Mo
• Han Dae Sung
• Yu Jin Hwan
• Jung Wook
• Kim Duk Sang

Classifications

• F02B23/0696

  W-piston bowl, i.e. the combustion space having a central projection pointing towards the cylinder head and the surrounding wall being inclined towards the cylinder wall · CPC title

• F02B23/0651

  the fuel spray impinging on reflecting surfaces or being specially guided throughout the combustion space · CPC title

• F02B23/0687

  Multiple bowls in the piston, e.g. one bowl per fuel spray jet · CPC title

• F02B19/14 Primary

  with compression ignition · CPC title

• F02B23/0693

  the combustion space consisting of step-wise widened multiple zones of different depth · CPC title