JPS6218662Y2 - - Google Patents

Description

[Detailed explanation of the idea] [Industrial application field]

The present invention relates to a piston for an internal combustion engine, and particularly to one that improves intake efficiency, exhaust efficiency of burned gas, and combustion efficiency due to turbulence of air-fuel mixture within a cylinder.

[Conventional technology and problems]

In order to improve combustion efficiency in an internal combustion engine, it is sufficient to generate a gas flow in the air-fuel mixture sucked into the cylinder to speed up flame propagation when ignited by the spark plug. Some products, such as high swirl ports and masked sheets, cause swirls during inhalation. However, although the flow of the air-fuel mixture is particularly required at the time of ignition near the end of the compression stroke and immediately after ignition, the above-mentioned method has little gas flow remaining by this time and is therefore ineffective. Another method is to create turbulence at the end of the compression stroke by squeezing between the inner wall of the combustion chamber and the piston, but this is not effective at low engine speeds, and the turbulence continues up to the center of the combustion chamber. No effect can be expected, and there is little effect on disturbing the area around the plug. Next, to improve the intake efficiency, for example, there is supercharging using a turbocharger, etc., but it goes without saying that the structure is extremely complicated. Regarding improving the exhaust efficiency of burnt gas, for example,
There is a prior art in Publication No. 63815, which separates the top of the piston from the main body and makes it expandable and retractable using a spring.The problem is that the top of the piston stretches during the intake stroke, which deteriorates the filling efficiency of the intake air-fuel mixture. . Incidentally, there is a prior art similar to the present invention, for example, in Japanese Utility Model Publication No. 47-20567, which protects the piston from heat during combustion by embedding a heat-resistant plate in the top of the piston. The purpose, structure, and effects are completely different.

[Means to solve the problem]

In view of these circumstances, the present invention has been developed by attaching a rocking plate to the top of the piston to which the exhaust valve end is fixed. Shake it like this,
It is an object of the present invention to provide a piston that improves suction efficiency in the suction stroke, gas discharge efficiency in the exhaust stroke, and combustion efficiency due to turbulence generated during combustion.

【Example】

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings. In FIGS. 1 and 2, reference numeral 1 is a cylinder, 2 is a piston inserted into the cylinder 1 and reciprocating up and down; 3 is a combustion chamber;
Suction and exhaust ports 4 and 5 communicating with this combustion chamber 3 are provided with suction and exhaust valves 6 and 7, respectively. In this configuration, a rocking plate 8 smaller in diameter than the top 2' of the piston 2 is attached to the top 2' of the piston 2 by fixing its end on the exhaust valve 7 side with screws 9. The rocking plate 8 is made of a heat-resistant and highly elastic material such as SUH3, SUH4, etc., and the acceleration when the piston 2 reciprocates between the top dead center and the bottom dead center is The acceleration changes from large at the dead center to small along the way, and the direction of the acceleration is reversed on the outward and return journeys, so it uses this inertial force to swing elastically like a fan. There is.
The deflection of the rocking plate 8 in this case can be controlled by appropriately setting the spring constant of the suction and exhaust valves 6 and 7.
will not interfere with it when it opens. Next, the operation of the present invention constructed as described above will be explained using FIG. is free without being subjected to residual gas pressure. Therefore, when the piston 2 rises at high speed from the bottom dead center and suddenly decreases in speed before reaching the top dead center, the rocking plate 8 is suddenly bent upward by inertia force using the side fixed by the screws 9 as a fulcrum.
The burnt gas remaining in the combustion chamber 3 is pushed out by the stirring action at this time. Since the screw 9 is installed on the exhaust valve side, when the rocking plate 8 is bent upward as shown in FIG. 1, the burnt gas can be pushed out more effectively. Next, in the intake stroke, the piston 2 descends at high speed at first, and the speed decreases as it approaches the bottom dead center, and the rocking plate 8 lags behind the piston 2.
In the first half of the stroke, the rocking plate 8 is bent upward, and returns to touch the piston top 2' after the halfway point. On the other hand, at this time, the negative pressure inside the cylinder 1 is large, and the opening degree of the intake valve 6 is also large, and in addition to this, the negative pressure increases due to the swinging movement caused by the return of the rocking plate 8, thereby promoting intake. In the compression stroke, the air-fuel mixture in the cylinder 1 is compressed by the rise of the piston 2 and acts on the upper part of the rocking plate 8, but the compressed air-fuel mixture flows into the gap between the lower part of the rocking plate 8 and the piston top 2'. The difference in pressure on both sides of the rocking plate 8 is offset by the pressure difference between the two sides of the rocking plate 8. Therefore, as in the case of the exhaust stroke, the rocking plate 8 bends upward due to inertia before the top dead center, but is immediately returned by the elastic restoring force of the rocking plate 8, and at this time, the rocking plate 8 and The air-fuel mixture between the piston top 2' is ejected and a turbulent flow is generated. In the process, it is ignited by the spark plug and explodes, but the large combustion gas pressure at this time pushes the rocking plate 8 further against the piston top 2', which causes the rocking plate 8 and the piston top 2' The gas between the two is ejected toward the flame, creating turbulence in the air-fuel mixture during flame propagation, and increasing the combustion rate. Note that the shape of the rocking plate 8 is not limited to a circular shape;
It may be elongated and wider than the exhaust ports 4 and 5, and in a bathtub-type combustion chamber, it may act within the combustion chamber excluding the squishy portion.

[Effect of the idea]

As is clear from the above explanation, according to the present invention, the rocking plate 8 attached to the piston top 2' bends up and down like a fan due to inertia and combustion gas pressure at the time of explosion, resulting in negative pressure during the intake stroke. Increasing the intake efficiency and pushing out the exhaust gas in the exhaust stroke,
Gas exhaust efficiency is improved. Furthermore, during the compression stroke and subsequent explosion, turbulence is generated in the air-fuel mixture, increasing the combustion rate and improving combustion efficiency.

[Brief explanation of the drawing]

Figure 1 is a side view of the piston according to the present invention, Figure 2 is a side view of the piston according to the present invention;
The figure is a plan view of the same, and FIG. 3 is a diagram showing the operating state. 2... Piston, 2'... Piston top, 8...
...Swing plate.

Claims (1)

[Scope of utility model registration request] A rocking plate having an exhaust valve side end fixed to the top of the piston is attached, and the rocking plate is rocked by the inertial force during reciprocating movement of the piston and the combustion gas pressure during the explosion stroke. Piston to do.