Internal-combustion engines – Combustion chamber means having fuel injection only – Combustible mixture stratification means
Reexamination Certificate
2000-03-29
2001-07-24
Solis, Erick (Department: 3747)
Internal-combustion engines
Combustion chamber means having fuel injection only
Combustible mixture stratification means
C123S298000, C123S305000
Reexamination Certificate
active
06263855
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a direct fuel injection-type spark-ignition internal combustion engine.
2. Description of the Related Art
There has heretofore been known the stratified charge combustion engine realized the directly injected fuel into a cylinder to form a mixture (hereinafter referred to as combustible mixture) that can be favorably ignited only in the vicinity of a spark plug, at the ignition timing, to burn a total lean mixture in the cylinder. To carry out stratified charge combustion, in general, the fuel injector injects fuel in the latter half period of the compression stroke. It is intended that the thus injected fuel proceeds into a concave cavity formed in the top of the piston, is vaporized by absorbing heat from the wall surfaces of the cavity, is deflected by the shape of the cavity toward the spark plug, and forms a combustible mixture near the spark plug.
In the direct fuel injection-type spark-ignition internal combustion engine for performing the stratified charge combustion, in general, the spark plug is arranged nearly at the center in the upper part of the cylinder, and the fuel injector is arranged in the periphery in the upper part of the cylinder. The piston cavity is located from nearly the central portion of the top surface of the piston to the periphery of the top surface of the piston on the side of the fuel injector. The piston cavity has a bottom wall and side walls which are spark plug side and fuel injector side. Fuel injected into the cavity collides with the bottom wall of the cavity, thereafter proceeds toward the spark plug side wall along the bottom wall, and is deflected toward the spark plug by the spark plug side wall.
In order to promote the fuel vaporization utilizing the heat of the wall surface of the cavity, the distance for moving fuel along the wall surface of the cavity must be lengthened so that the injected fuel stays in contact with the wall surface of the cavity for an extended period. In order to realize this without changing the shape of the cavity, it has been proposed to inject fuel at a relatively large acute angle with respect to the bottom wall of the cavity. This makes it possible to bring the position where fuel collides with the bottom wall away from the spark plug side wall of the cavity, maintaining the same injector hole position, compared with when the fuel is injected at a relatively small acute angle, and, hence, to extend the distance for moving fuel along the bottom wall of the cavity.
When the fuel is injected at a relatively large acute angle with respect to the bottom wall of the cavity, however, fuel which has collided with the bottom surface is diverted and all of the fuel does not proceed toward the spark plug side wall along the bottom surface; i.e., a part of the fuel proceeds toward the fuel injector side wall along the bottom surface.
Accordingly, the quantity of the combustible mixture formed near the spark plug via the spark plug side wall of the cavity is decreased, so that the engine output is also decreased. Furthermore, the mixture formed by fuel proceeded toward the fuel injector side wall of the cavity cannot be favorably burned, and unburned fuel may be emitted in increased amounts.
SUMMARY OF THE INVENTION
The objective of the present invention is to provide a direct fuel injection spark-ignition internal combustion engine which produces the engine output as intended in the stratified charge combustion mode; in this engine, fuel is injected toward the bottom wall of a cavity formed in the top surface of a piston so as to proceed mainly toward the spark plug side wall of the cavity along the bottom wall, and the fuel is led toward the vicinity of the spark plug and in which, even when the fuel that has collided with the wall surface of the cavity is diverted into toward the spark plug side wall of the cavity and toward the fuel injector side wall, all of the injected fuel is burned as the combustible mixture.
According to the present invention, provided is a direct fuel injection-type spark-ignition internal combustion engine comprising a spark plug, a fuel injector and a cavity formed in the top surface of the piston, the cavity having a bottom wall, a spark plug side wall and a fuel injector side wall, the fuel injector injecting fuel toward the bottom wall of the cavity in stratified charge combustion, the fuel mainly proceeding toward the spark plug side wall of the cavity along the bottom wall, being deflected by the spark plug side wall and being led to the vicinity of the spark plug, wherein the fuel injector side wall of the cavity is provided with a deflecting portion, and if a part of the injected fuel proceeds toward the fuel injector side wall along the bottom wall of the cavity, the part of the fuel is led to the vicinity of the spark plug by the deflecting portion.
The present invention will be more fully understood from the description of preferred embodiments of the invention set forth below together with the accompanying drawings.
REFERENCES:
patent: 5720253 (1998-02-01), Matoba et al.
patent: 5806482 (1998-09-01), Igarashi et al.
patent: 5915353 (1999-06-01), Matsumara
patent: 6035822 (2000-03-01), Suzuki et al.
patent: 6035823 (2000-03-01), Koike et al.
patent: 6125817 (2000-10-01), Piock et al.
patent: 6125818 (2000-10-01), Okamoto et al.
patent: 6186113 (2001-02-01), Hattori et al.
patent: 9-158736 (1997-06-01), None
Abe Shizuo
Fujikawa Taketoshi
Hattori Fumiaki
Kashiwagura Toshimi
Kobayashi Tatsuo
Oliff & Berridg,e PLC
Solis Erick
Toyota Jidosha & Kabushiki Kaisha
LandOfFree
Direct fuel injection-type spark-ignition internal... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Direct fuel injection-type spark-ignition internal..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Direct fuel injection-type spark-ignition internal... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2455193