JP2003293803A - Method to lengthen expansion process of cylinder injection gasoline engine further than real compression process of gasoline engine in terms of stroke - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method to lengthen the expansion process than the real compression process of a cylinder injection gasoline engine in terms of a stroke. <P>SOLUTION: During a compression process, an exhaust valve is opened to a bottom dead center and closed this side of a top dead center. Further, as a countermeasure when the exhaust valve is too opened during a compression process, a suction valve is opened and closed at a bottom dead center before over expansion turns into resistance of rotation during an expansion process. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for making a stroke of a cylinder injection gasoline engine longer than a true compression step in terms of stroke.

[0002]

2. Description of the Related Art In a conventional cylinder injection gasoline engine, theoretically, compression ratio = expansion ratio (actually, it differs depending on valve timing, etc.).

[0003]

In the conventional cylinder-injection gasoline engine, the theory is that the compression ratio = expansion ratio causes the exhaust valve to open before the expansion is complete and the energy generated due to the explosion. There was a problem that (power, torque) was discharged.

The present invention relates to a direct injection gasoline engine,
The purpose is to obtain a method of taking a stroke that is longer than the step of really compressing in terms of stroke, and further to obtain a measure during the expansion step when using the method. I am trying.

[0005]

In order to achieve the above object, in the method of taking the stroke of the cylinder injection gasoline engine of the present invention, the step of expanding the cylinder rather than the step of really compressing is longer. Opens the exhaust valve at the bottom dead center and closes just before the top dead center during the compression process.

Further, as a countermeasure against excessive opening of the exhaust valve during the compression process, the intake valve is opened and closed at the bottom dead center during the expansion process before it expands too much and becomes resistance to rotation.

[0007]

In the method of taking the stroke of the cylinder injection gasoline engine having the above-described structure, the step of expanding the cylinder as compared with the step of really compressing is longer than that of the stroke.
During the compression process, the process of compression ratio <expansion ratio can be performed because the exhaust valve is opened at the bottom dead center and closed just before the top dead center.

Further, as a measure against excessive opening of the exhaust valve during the compression process, the intake valve is opened and closed at the bottom dead center during the expansion process before it expands excessively and becomes resistance to rotation. Therefore, the ratio of compression ratio <expansion ratio can be increased.

[0009]

EXAMPLES Examples will be described with reference to the drawings.
In FIGS. 1 to 4, the movement of the valve in the compression process and the expansion process of the cylinder injection gasoline engine is such that the expansion process is longer than the compression process in terms of stroke. 1 to FIG. 4. FIG. 1 to FIG. 4 are shown in FIG. 1. The compression process-1 The intake valve is closed, the exhaust valve is opened at the bottom dead center, and is closed just before the top dead center (FIG. 1). The exhaust valve shown in Fig. 2 is a diagram assuming that the exhaust valve will close when the piston moves up by about two-thirds, and is a diagram immediately before closing.). Fig. 2 Compression process-2 (gasoline injection / ignition) The intake valve and exhaust valve are closed. Fig. 3 Expansion step-1 (combustion) The intake valve opens before it expands too much and becomes a resistance to rotation, and the exhaust valve closes (in the intake valve shown in Fig. 3, the piston is about three quarters, It is a diagram that is assumed to open when it descends, and also a diagram immediately after opening.). Fig. 4 Expansion step-2 The intake valve is closed at bottom dead center and the exhaust valve is also closed. (The valve timings of the valves shown in FIGS. 1 to 4 are not included because they differ depending on the purpose of the engine, the number of revolutions, the rise and fall of the revolutions, the compression ratio, etc.) .).

[0010]

Since the present invention is constructed as described above, it has the following effects.

In a method of taking a stroke of a cylinder injection gasoline engine, which expands more than a compression actually, in terms of stroke, the exhaust valve is opened at the bottom dead center during the compression step and the top dead center is reached. Due to the fact that it closes just before the point, the process of compression ratio <expansion ratio can be performed, and the energy generated by the explosion when consuming the same amount of fuel as the conventional direct injection gasoline engine. More (power, torque) can be transmitted to the piston and crank shaft.

As a countermeasure against excessive opening of the exhaust valve during the compression process, the intake valve is opened and closed at the bottom dead center during the expansion process before it expands too much and becomes a resistance to rotation. Therefore, the resistance during rotation is reduced, and the ratio of compression ratio <expansion ratio is high, and the expansion process can be performed smoothly.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an embodiment of a process of a cylinder injection gasoline engine (compression process-1).

FIG. 2 is a vertical cross-sectional view showing an embodiment of a process of a cylinder injection gasoline engine (compression process-2).

FIG. 3 is a vertical cross-sectional view showing an embodiment of a process of a cylinder injection gasoline engine (expansion process-1).

FIG. 4 is a vertical cross-sectional view showing an example of a process of a cylinder injection gasoline engine (expansion process-2).

[Explanation of symbols]

1 Intake valve (also serves as a valve that opens at top dead center during the intake stroke and closes at bottom dead center, and a valve that opens before expanding too much and becomes resistance to rotation during the expansion stroke and closes at bottom dead center) 2 Exhaust valve (a valve that opens at bottom dead center and closes at top dead center during the exhaust stroke, and a valve that opens at bottom dead center and closes slightly before top dead center during the compression stroke, A valve that doubles as a fuel cell.) 3 Plug 4 Fuel injector 5 Piston 6 Intake pipe 7 Exhaust pipe

Claims (2)

[Claims] 1. An in-cylinder injection gasoline engine (FIGS. 1 to 4) in which an exhaust valve is opened at bottom dead center and closed just before top dead center during a compression process. 2. The exhaust valve according to claim 1, as a measure against excessive opening during the compression process, opens the intake valve during the expansion process before it expands too much and becomes resistance to rotation. In-cylinder injection gasoline engine, closed at points (Figs. 1 to 4).