JPS59203817A - Internal-combustion engine - Google Patents

Abstract

PURPOSE:To inhibit the generation of knocking positively, and to improve an engine output and the specific consumption of fuel by forming a combustion chamber by a recess shaped to the lower surface of a cylinder head and a recess shaped to the top surface of a piston. CONSTITUTION:A combustion chamber 5 is formed by a recess 6 shaped to the lower surface of a cylinder head 2 and a recess 7 shaped to the top surface of a piston 3. An electrode for an ignition plug 8 faces into the combustion chamber 5 while an intake port 10 with an intake valve 9 and an exhaust port with an exhaust valve are opened. The whole piston 3 is made of an aluminum alloy, and the heat treansfer of a squash area 12 in the piston 3 is improved. Ceramics 14 are fixed to the top surface section of the piston 3, and the heat transfer of the squash area 12 in the recess 7 is lowered. Accordingly, an output of the engine and the specific consumption of fuel can be enhanced because the generation of knocking can be inhibited positively.

Description

DETAILED DESCRIPTION OF THE INVENTION The first misfire relates to a spark ignition internal combustion engine with an improved combustion chamber to improve fuel consumption.

In order to improve the thermal efficiency of an internal combustion engine, it is necessary to increase the compression ratio (or inertia). There is a certain limit to the fuel efficiency (G).And if you suppress the generation of horn kinks and IE by improving the combustion chamber, you can increase the white ratio by that much. ]・In order to suppress the horn kink by improving the combustion chamber, 1. The distance from the ignition point looking into the combustion chamber to the hot water in the combustion chamber, that is, the flame propagation distance, should be shortened to reduce the combustion chamber.

(2) To increase the flame propagation speed and shorten the combustion time by creating turbulent air-fuel mixture flow in the combustion chamber.

■ Raise the temperature inside the combustion chamber and maintain it in one state (one state) to lower the temperature around the combustion chamber.

It is well known that there are means such as i;j l? as a specific example of obtaining the second means. J
It is known that a squish area is formed around the ire chamber, and the squish flow from the squish area generates turbulence in the combustion chamber r'i.

- Utility Model Application Publication No. 56-129525 and Utility Model Application Publication No. 56-45120 i as prior art)
It is proposed that a squish area be formed around a combustion chamber formed by recessing the lower surface of the navel 1 to surround the combustion chamber. Forming the squish area around the combustion chamber in this way makes the combustion chamber more compact, and is therefore also effective for the first means. However, in these prior art, the top surface of the piston is completely flat with no recess in the center, while the bottom surface of the cylinder head is recessed to form the combustion chamber.
Increase the squish area to further compact the combustion chamber +-
In order to achieve <=, the depth of the recess on the underside of the Norinda head must be made deep. However, if the depth of the recess at the bottom of the link hesode +n+ is increased, the effect of the squish flow from the squish area cannot be equally applied to the entire area of the combustion chamber, so the effect of the second means is reduced. Moreover, the top of the screw (-) + M+ has a perfect flat surface as mentioned above, and the heat escapes uniformly from the top surface b), so even if the inside of the combustion chamber is kept at a high temperature, In other words, the effect of the third means was insufficient.

The present invention is based on the conventional method in which a squish area is formed around the combustion chamber formed by recessing the lower surface of the cylinder spatula l-, and a combustion chamber is also formed on the top surface of the piston. By providing a recess in the cylinder spatula 1 for forming the combustion chamber, it is possible to make the combustion chamber more compact and increase the ski run unit without reducing the influence of the squish flow on the entire area of the combustion chamber.
Either or both of the recess on the side of
This means that it is possible to effectively implement the means described above.

The present invention will be explained below with reference to one song of the embodiment. In the figure, (1) is a cylinder flock, (2) is a cylinder head, and (3) is a piston that reciprocates within the cylinder hore (4) of the cylinder block (], ). are shown respectively.

(5) indicates a combustion chamber, which includes a recess (6) formed in the lower surface of the cylinder head (2) and a recess (7) formed in the top surface of the pinuton (3). It consists of
Inside the combustion chamber (5) there is an ignition valve (8) screwed onto the cylinder head (2), an intake hole with an intake valve (9) and an exhaust boat with an exhaust valve. ing.

A combustion chamber (5) is located on the lower surface of the cylinder head (2).
and the region outside the recess (7) for forming the combustion chamber (5) on the top surface of the piston (3) ) are at the top dead center of the combustion chamber (5) and approach each other.
The squish area (+1) (IJ) is formed so as to surround almost the entire circumference of the combustion chamber (5) so as to eject squish flow into the combustion chamber (5).

The entire piston (3) is made of aluminum alloy, and the squish area 0 that can be attached to the screw 1 (3) is
4 while increasing heat transfer in the mother of the piston (3),
, a hole 11i'IIQ; is formed in the corresponding part of the recess (7) as shown in Figure 1G, or this recess (7) is By forming a material (IJ) with a low heat transfer coefficient such as a ceramic plate fixed on a part of the top surface of the screws 1 to (3), the heat transfer in the recess (7) is reduced. The heat transfer in the squish area surrounding the

In this case, in another embodiment, as shown in FIG.
to increase heat transfer in the squish area (1'l), while recesses (6) in the cylinder head (2)
It is also possible to have a material with low heat transfer such as ceramic attached to the inner surface of the plate (of course, the one shown in Fig. 3 can be combined with the one shown in Fig. 1 or Fig. 2). Needless to say, it's a good thing.

In this configuration, at the end of the compression stroke as the piston (3) rises, the squish area at the screw (3) or the squish area at the cylinder spatula 1 to (2) approaches 0°C. During this time, a squish action occurs, and the squish flow ejects from the periphery of the combustion chamber (5) toward the combustion chamber (5). The squish area (111 (111) from between 1'4 and The flow is
The combustion chamber (
5) Since the squish flow will be ejected into the interior, the influence of the squish flow will surely reach every corner of the image recesses (6) and (7) even if the depth of both recesses (6 and 7) becomes somewhat deeper. I can do something.

Therefore, the height of the combustion chamber (5) can be increased by this distance, and the radius of the combustion chamber (5) can be decreased.
While the radial dimension of the combustion chamber (5) is reduced, the area of the skiran unilia (1) α can be increased, and the squish flow can be made stronger.

Moreover, the squish area on the cylinder head (2) side (
1υ and piston (3) side squish area o4 (high heat transfer), cylinder head (2) side recess (
6) and/or the heat transfer in the recess (7) on the piston (3) side is configured to be lower than the skillan unitia (11) (la), so that heat loss from the combustion chamber (5) is reduced and the heat transfer from the combustion chamber (5) is reduced. 5) While keeping the inside at a high temperature,
The amount of heat dissipated from both squish areas (11) can be increased (91) in the vicinity of the combustion chamber (5), that is, in the area far from the ignition column (8).

As described above, in the present invention, the combustion chamber into which the ignition column, the intake boat, and the exhaust boat open are taken over by a recess formed by recessing the lower surface of the cylinder head and a recess formed by recessing the additional white of the piston. , a squish area surrounding substantially the entire circumference of the combustion chamber is formed on the lower surface of the cylinder spatula 1 and the top surface of the cylinder spatula 1 in the region outside the combustion chamber; The structure is characterized in that the heat transfer in one or both of the combustion chamber forming recesses is lower than the heat transfer in the squish area surrounding the recess, and the squish flow over the entire area of the combustion chamber is reduced. It is possible to reduce the combustion chamber without reducing the effect, and the flame propagation distance can be further shortened (
While this can make the air flow more powerful, it also keeps the temperature inside the combustion chamber high while keeping the temperature around the combustion chamber low, so these things work together to significantly promote combustion inside the combustion chamber. At the same time, the occurrence of knocking can be reliably suppressed. As a result, the compression ratio can be increased enough to suppress the occurrence of knocking, which has the effect of improving engine output and fuel consumption.

[Brief explanation of the drawing]

The drawings show joint cross-sectional views of main parts of the engine according to embodiments of the present invention, and FIG. 1 is a diagram of the first embodiment, FIG. 2 is a diagram of the second embodiment, and FIG. 3 is a diagram of the third embodiment. This is a diagram. (])...Cylinder flock, (2)...Cylinder head, (3)...Piston, (5)...Combustion chamber, (8
)・Single spark column, (10...Intake port 1-, f6) (7
)・Concavity, α1) (12,l...Sukitsuyu area. Ward Ward

Claims (1)

[Claims] (1) The combustion chamber, which looks about one ignition and has an intake boat and an exhaust boat open, is composed of a recess formed by recessing the lower surface of the cylinder head and a recess formed by recessing the top surface of the piston. A squish area surrounding substantially the entire circumference of the combustion chamber is formed on the lower surface of the cylinder head and the top surface of the piston in the outer region, while either a combustion chamber forming recess in the cylinder head or a combustion chamber forming recess in the piston. An internal combustion engine characterized in that the heat transfer in one or both of the squish areas is lower than the heat transfer in the surrounding squish area.