Internal-combustion engine

Patent metadata

Field	Value
Publication number	US-9803539-B2
Application number	US-201213681422-A
Country	US
Kind code	B2
Filing date	Nov 20, 2012
Priority date	Nov 25, 2011
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

An internal-combustion engine includes a cylinder, a piston, a spark plug, and a fuel injection valve. The piston includes a top surface and a cavity provided in the top surface. The cavity includes a bottom surface, a vertical wall, a first sidewall, and a second sidewall. The fuel injection valve includes a plurality of injection ports from which a plurality of fuel mists are to be obliquely injected toward the top surface of the piston in respectively different directions at a predetermined crank angle in a compression stroke. The cavity extends from a position close to a center of the piston toward the fuel injection valve when viewed from above the top surface of the piston. The first and second sidewalls extend toward the fuel injection valve when viewed from above the top surface of the piston.

First claim

What is claimed is:

1. An internal-combustion engine comprising:
a cylinder including a combustion chamber;
a piston provided in the cylinder to reciprocate in the cylinder and including a top surface and a cavity provided in the top surface and having a front half and a rear half, the cavity comprising:
a bottom surface;
a vertical wall at the front half of the cavity provided near a center of the top surface and standing substantially perpendicularly from the bottom surface, the vertical wall extending from the bottom surface to the top surface;
a first sidewall extending toward a first end of the vertical wall and extending from the bottom surface to the top surface;
a second sidewall extending toward a second end of the vertical wall, the second end being opposite to the first end in the vertical wall, the second sidewall extending from the bottom surface to the top surface;
a first curved transition wall portion between the first sidewall and the vertical wall; and
a second curved transition wall portion between the second sidewall and the vertical wall;

a spark plug provided above the combustion chamber to generate a spark that ignites a mixture of fuel and air in the cylinder and to face toward a position close to a center of the combustion chamber; and
a fuel injection valve facing the combustion chamber and including a plurality of injection ports from which a plurality of fuel mists are to be obliquely injected toward the top surface of the piston in respectively different directions at a predetermined crank angle in a compression stroke, the cavity extending from a position close to a center of the piston toward the fuel injection valve when viewed from above the top surface of the piston, the first and second sidewalls extending toward the fuel injection valve when viewed from above the top surface of the piston, the plurality of injection ports comprising:
a first injection port from which a first fuel mist is to be injected at the predetermined crank angle toward the vertical wall and an adjoining portion adjoining the vertical wall, the adjoining portion being provided in the top surface of the piston, the top surface of the piston including an uppermost surface of the piston;
second injection ports from which a pair of second fuel mists are to be injected at the predetermined crank angle to respectively collide with the first and second sidewalls, the first and second sidewalls being provided to guide the second fuel mists to flow along the first and second sidewalls toward the vertical wall, the first and second curved transition wall portions being provided to guide the second fuel mists to flow from the first and second side walls toward the vertical wall; and
a third injection port from which a third fuel mist is to be injected to collide with the bottom surface of the cavity, the bottom surface including a lowest surface of the cavity, the bottom surface being provided to lift the first fuel mist and the second fuel mists to flow toward the spark plug together with the third fuel mist after the third fuel mist collides with the lowest surface of the cavity,

wherein a distance between the first and second sidewalls continuously reduces beginning within the rear half of the cavity and continuing to the first curved transition wall portion along a direction toward the vertical wall.

2. The internal-combustion engine according to claim 1 , wherein the first injection port includes a center axis along which the first fuel mist is to be injected from the first injection port, the center axis of the first injection port being provided to direct at the predetermined crank angle toward the adjoining portion provided in the top surface of the piston, the bottom surface of the cavity being provided to reflect the third fuel mist so that the first fuel mist is directed toward the spark plug by the third fuel mist having been reflected by the bottom surface of the cavity.

3. The internal-combustion engine according to claim 1 ,
wherein the plurality of injection ports further comprises a pair of fourth injection ports from which a pair of fourth fuel mists are to be injected at the predetermined crank angle toward respective outer sides of the pair of second fuel mists, and toward a side closer to the fuel injection valve than the second fuel mists, and
wherein the fourth fuel mists are injected at the predetermined crank angle from the fourth injection ports to respectively collide with portions other than the cavity in the top surface of the piston.

4. The internal-combustion engine according to claim 3 , wherein the first fuel mist, each of the pair of second fuel mists, the third fuel mist, and each of the pair of fourth fuel mists are of a same amount as each other.

5. The internal-combustion engine according to claim 1 , wherein the third fuel mist is injected at the predetermined crank angle from the third injection port toward a space between the second fuel mists.

6. The internal-combustion engine according to claim 1 , wherein the first injection port includes a center axis and the first fuel mist is injected from the first injection port to align with the center axis of the piston.

7. An internal-combustion engine comprising:
a cylinder including a combustion chamber;
a piston provided in the cylinder to reciprocate in the cylinder and including a top surface and a cavity provided in the top surface and having a front half and a rear half, the cavity comprising:
a bottom surface;
a vertical wall at the front half of the cavity provided near a center of the top surface and standing substantially perpendicularly from the bottom surface, the vertical wall extending from the bottom surface to the top surface;
a first sidewall extending toward a first end of the vertical wall and extending from the bottom surface to the top surface;
a second sidewall extending toward a second end of the vertical wall, the second end being opposite to the first end in the vertical wall, the second sidewall extending from the bottom surface to the top surface;
a first curved transition wall portion between the first sidewall and the vertical wall; and
a second curved transition wall portion between the second sidewall and the vertical wall;

a spark plug provided above the combustion chamber to generate a spark that ignites a mixture of fuel and air in the cylinder and to face toward a position close to a center of the combustion chamber; and
a fuel injection valve facing the combustion chamber and including a plurality of injection ports from which a plurality of fuel mists are to be obliquely injected toward the top surface of the piston in respectively different directions at a predetermined crank angle in a compression stroke, the cavity extending from a position close to a center of the piston toward the fuel injection valve when viewed from above the top surface of the piston, the first and second sidewalls extending toward the fuel injection valve when viewed from above the top surface of the piston, the plurality of injection ports comprising:
a first injection port from which a first fuel mist is to be injected at the predetermined crank angle toward the vertical wall and an adjoining portion adjoining the vertical wall, the adjoining portion being provided in the top surface of the piston;
second injection ports from which a pair of second fuel mists are to be injected at the predetermined crank angle to respectively collide with the first and second sidewalls, the first and second sidewalls being provided to guide the second fuel mists to flow along the first and second sidewalls toward the vertical wall, the first and second curved transition wall portions being provided to guide the second fuel mists to flow from the first and second side walls to

Assignees

• Honda Motor Co Ltd

Inventors

• Sato Hiroaki
• Motohashi Yasuhiro
• Kitano Haruya
• Takahashi Masayoshi
• Hirano Hiromitsu
• Tanaka Shun

Classifications

• F02M61/1813

  Discharge orifices having different orientations with respect to valve member direction of movement, e.g. orientations being such that fuel jets emerging from discharge orifices collide with each other · CPC title

• Y02T10/125

  Cross-Sectional Technologies · mapped topic

• F02B23/0651 Primary

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

• F02B2023/103

  the injector having a multi-hole nozzle for generating multiple sprays · CPC title

• F02B23/104

  the injector being placed on a side position of the cylinder · CPC title