Variable-displacement engine

Abstract

The invention discloses a variable-displacement engine and belongs to the technical field of engines. The variable-displacement engine is characterized in that a cylinder I, a cylinder II, a cylinder III and a cylinder IV on an internal direct-injection engine are respectively and correspondingly provided with one gas inlet pipe, and are respectively connected with a partitional gas inlet mechanism of a throttle valve by gas inlet pipe openings of the cylinder I, the cylinder II, the cylinder III and the cylinder IV; an outlet of the end part of an exhausting main pipe is connected with a three-way catalytic converter; an outlet of the side surface of the exhausting main pipe is connected with an inlet of a waste gas return pipe I; an outlet of the waste gas return pipe I is connected with a waste gas return pipe II by a throttle valve connector III with a throttle valve III; the waste gas return pipe II is connected with a gas inlet pipe of the cylinder IV of the partitional gas inlet mechanism of the throttle valve; an electric control unit is respectively connected with the three throttle valves, a three-cylinder injector and a four-cylinder injector fixedly connected on a cylinder cover of the internal direct-injection engine. The variable-displacement engine disclosed by the invention has the advantages that after the displacement is changed, the excess air factor is 1 when the engine is in working can be guaranteed, so that the three-way catalytic converter works normally, the emission can be improved, the cold-heat alternation in the cylinders can be avoided, the service life of the engine can be prolonged, the cost is low and the oil-saving effect is good.

Description

technical field [0001] The invention belongs to the technical field of engines, and in particular relates to a variable-displacement engine capable of improving fuel-saving efficiency. Background technique [0002] Variable displacement technology refers to stop some cylinders working under small load conditions, and inject more fuel to other cylinders, so that it can produce the same power as all cylinders, but the total fuel injection volume will be reduced, so that It will save some fuel. It can be seen from the load characteristics of gasoline engines that the fuel consumption rate of the engine will be high when the engine is working at a small load, but the fuel consumption rate will be reduced at medium and high loads. The effect is greater, and when the throttle opening is small, the ventilation of the cylinder is not good, the residual exhaust gas increases, and the combustion is not good, resulting in an increase in fuel consumption. As the energy crisis becomes ...

AI Technical Summary

Problems solved by technology

When the engine is running on the road, the load is not constant. Sometimes it is necessary to stop the work of some cylinders, and sometimes it is necessary to work all the cylinders. The cylinders that stop working are still fed with air, and the air will take away the heat generated by the previous cylinders when they were all working, reducing the temperature in the cylinders, which not only causes additional heat loss to the engine, but also the alternating process of cold and heat will lead to the use of the engine Decreased lifespan

Furthermore, it will also lead to a decline in the conversion capability of the post-processing device. This is mainly because most of the current gasoline engine post-processing devices are three-way catalytic converters. This device has the best conversion efficiency when the excess air coefficient is 1. If it does not work If the cylinder continues to enter the air, it will cause the exhausted gas air to increase, so that the excess air coefficient is much greater than 1, and the catalytic conversion efficiency of the post-processing device will decrease, resulting in worsening emissions

[0003] Some high-end cars are equipped with a stop valve mechanism, which is a mechanism that can stop the valve movement while stopping the fuel injection, and keep the intake and exhaust valves in a closed state. This mechanism is not only complicated, but also requires high structural precision. Its movement is also more troublesome, requiring accurate and rapid

On the other hand, now most of the family cars are mostly four-cylinder engines, and there are almost no valve stop mechanisms that are really applied to small-displacement engines, and major automobile companies have not yet launched this type of engine.

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