Exhaust scavenged engine

Abstract

The invention provides an exhaust gas scavenging engine which comprises a cylinder body, a piston, an exhaust duct, a bent shaft cavity, a scavenging duct, a scavenging port and a crank case. An exhaust gas backflow duct communicated with the exhaust duct and the scavenging duct is arranged on the cylinder body, and a check valve opening from the exhaust gas backflow duct to the scavenging duct is arranged at the gas outlet end of the exhaust gas backflow duct. When the exhaust gas scavenging engine works, exhaust gas is discharged from a gas outlet, the exhaust gas passes through the exhaust gas backflow duct to open the check valve to enter the scavenging duct, the exhaust gas enters the scavenging duct to enable mixed oil gas to be pressed to the bent shaft cavity, and backflow exhaust gas on an upper layer in the scavenging duct firstly enters a combustor and rapidly pushes residual exhaust gas in the cylinder to enter the exhaust duct to be discharged from the gas outlet when the scavenging port is opened. The exhaust gas scavenging engine conducts scavenging on the engine by using the exhaust gas, reduces original discharging of the engine, and accordingly controls discharging indexes of the engine.

Description

technical field [0001] The invention relates to the technical field of engines, more specifically, to an exhaust gas scavenged engine. Background technique [0002] Since the invention of the internal combustion engine, it has greatly promoted the development of human society and the improvement of people's living standards. The two-stroke gasoline engine is widely used in motorcycles and other portable machinery because of its high power, stable operation, simple structure and many advantages such as manufacturing. [0003] Now we widely use the two-stroke gasoline engine, since the exhaust gas after combustion in the cylinder combustion chamber is purged and ventilated with the combustible mixture, the fresh combustible mixture is first sucked into the crankcase, and when the piston goes down, the inside of the crankcase The compressed combustible gas enters the combustion chamber of the cylinder through the scavenging port, and the fresh mixed gas has the function of squ...

AI Technical Summary

Problems solved by technology

In order to keep as little exhaust gas as possible in the combustion chamber of the cylinder, there must be a part of the combustible mixture that is discharged from the exhaust port and wasted in vain without combustion.

At the same time, in the process of mixing with exhaust gas, a part of the mixed gas will decompose and produce toxic and harmful substances out of the machine due to the action of lack of oxygen and high-temperature exhaust gas, which will further aggravate and worsen the emission pollution.

At the same time, in order to minimize the gas exchange loss in the existing two-stroke gasoline engine, the scavenging port is designed to be lower than the exhaust port. However, when the piston moves upward, the scavenging port is closed first, and then the exhaust port is closed. During this period, that is, In the later stage of scavenging, part of the combustible gas in the combustion chamber of the cylinder is extruded out of the machine through the exhaust port, which not only wastes fuel, but also increases pollution

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