JP2000087751A - 2-cycle internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To clean up the exhaust gas and increase the output by blowing the pressurized air into the cylinder in the scavenging stroke for forced exhaust. SOLUTION: During the operation of a two-cycle engine, when a piston 2 approaches the bottom dead center due to combustion or explosion in a cylinder 1, the pressurized air is blown through an intake port 3, and thus the exhaust gas in the cylinder 1 is forcedly exhausted through an exhaust port 4. The operation proceeds to the compression stroke by closing the exhaust port 4 as the piston 2 rises. When the piston 2 reaches an appropriate position near the top dead center, fuel is blown from a fuel injection port 5 and a spark plug 6 is ignited, leading to combustion or explosion, generating power to press down the piston 2. Repetition of the above operations, the power for motion of the piston 2 is transmitted from a piston pin 7 to a crank 9 via a connecting rod 8, thereby rotating an output shaft.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] The present invention relates to an improvement of a two-stroke internal combustion engine.

2. Description of the Related Art A conventional two-stroke internal combustion engine has a simpler structure and a relatively higher output than a four-stroke internal combustion engine. However, unburned gas easily mixes with exhaust gas due to the air supply system, and the structure is lubricated. There is a disadvantage that it is difficult to produce a high-power one because of using a fuel mixed with oil.

[Problems to be Solved by the Invention]
In a cycle internal combustion engine, exhausted scavenging of burned waste gas in a cylinder is performed by blowing a new air-fuel mixture. Therefore, when the volume of the new air-fuel mixture is less than the required amount, the exhaust gas scavenging is not completely performed. When the volume of the air-fuel mixture is larger than the required amount, the new air-fuel mixture, that is, unburned gas is discharged and waste of fuel is reduced. Become. Also, the pressure change in the crankcase due to the piston up and down is used to inject a new air-fuel mixture into the cylinder,
At the same time, since the mixture is sucked into the crankcase, lubricating oil cannot be stored in the crankcase, and measures such as mixing lubricating oil into the fuel in advance are taken. There is a drawback that exhaust combustion may occur due to incomplete combustion.

Means for Solving the Problems The present invention enables exhaust gas to be completely exhausted at the end of a public combustion stroke of a piston and at the same time allows lubricating oil to be stored in a crankcase, thereby making exhaust gas cleaner. And the production of high-power engines.

[Means for Solving the Problems] In order to achieve the above object, in an internal combustion engine of the present invention, compressed air is blown into the cylinder from the outside to completely discharge burned gas. .

Embodiments of the present invention will be described with reference to the accompanying drawings based on embodiments. In FIG. 1, when the piston 2 approaches the bottom dead center due to combustion or explosion in the cylinder 1, pressurized air is blown from the air supply port 3 to forcibly exhaust waste air in the cylinder 1 from the exhaust port 4. Next, as the piston 2 rises, the exhaust port 4 is closed and enters the compression stroke. When the piston 2 reaches the top dead center as shown in FIG. The fuel is injected from the fuel injection port 5 at an appropriate timing near the top dead center of the piston 2, and then the piston 2 is pushed by the ignition plug 6 by combustion or explosion by diesel ignition or electric ignition. It is lowered and returns to the state of forced exhaust as shown in FIG. Thereafter, by repeating the above, the kinetic force of the piston 2 is transmitted from the piston pin 7 to the output shaft 10 through the connecting rod 8 through the crank 9. A lubricating oil 12 for lubricating a piston or the like is stored in a crankcase 11.
Is performed in the same manner as in a conventional four-stroke engine.

[Effects of the Invention] Since the present invention is configured as described above, it has the following effects.

Since the exhaust gas in the cylinder is completely scavenged, the efficiency of the engine is improved because the cylinder is filled only with a mixture of newly injected fuel and air.

Further, since only the waste gas in the cylinder is scavenged in the exhaust stroke, the unburned gas is not discharged.

Further, since the air supply does not pass through the inside of the crankcase, the lubricating oil can be stored in the lower portion, and the use of a mixed oil in which the lubricating oil is added to the fuel does not have to be used. The output engine can be used for manufacturing.

[0011] Compared to a four-cycle engine, almost twice the output can be obtained with the same displacement, and half or less cylinders are required to obtain the same output, making it possible to reduce the size and weight.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view when a piston of the present invention is near a bottom dead center.

FIG. 2 is a schematic sectional view when the piston of the present invention is at the top dead center.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder 2 Piston 3 Air supply port 4 Exhaust port 5 Fuel injection port 6 Spark plug 7 Piston pin 8 Connecting rod 9 Crank 10 Output shaft 11 Crankcase 12 Lubricating oil

Claims (1)

[Claims] 1. A two-stroke internal combustion engine using forced exhaust by blowing compressed air into a cylinder during a scavenging stroke.