Spontaneous intake type internal combustion engine for vehicles

Abstract

A naturally aspirated internal combustion engine for a vehicle having an operating range from a no-load range to a high-load high-speed range is controlled in accordance with the Miller cycle throughout the entire operation range including the high-load high-speed range, thereby further improving fuel consumption , while improving the productivity of the internal combustion engine with a simple structure, and, furthermore, suppressing an increase in cost and an increase in weight of the internal combustion engine. The naturally aspirated internal combustion engine E for a vehicle is equipped with a cylinder 2 in which a piston 8 can freely reciprocate, and an intake valve that opens and closes at a constant opening and closing time throughout the entire operating range from a no-load range to a high-load high-speed range. 35 and exhaust valve 36. The valve closing time of the suction valve 35 is set before the bottom dead center, or the prescribed valve closing time after the suction gas in the cylinder 2 flows back to the bottom dead center upstream of the suction valve 35 . In addition, the exhaust volume of the internal combustion engine E is set in the high-load high-speed region, and the internal combustion engine E can obtain the specified exhaust volume of the maximum required indicated output through the control of closing the intake valve 35 at the above-mentioned predetermined valve closing time.

Description

technical field [0001] The invention relates to a naturally aspirated internal combustion engine for vehicles operating in the form of a Miller cycle. Background technique [0002] As we all know, in previous reciprocating internal combustion engines, the closing time of the suction valve was set before the bottom dead center, or at the bottom dead point where the suction gas that had just flowed into the cylinder flowed back from the open suction valve to the bottom dead point of the suction hole. After the point, the internal combustion engine operates in the form of the so-called Miller cycle. This kind of internal combustion engine operating in the form of Miller cycle, compared with the internal combustion engine operating in the form of Otto cycle, reduces the compression pressure at the top dead center of the compression stroke (actual compression ratio). The form of the Torr cycle is the same, so, for the actual compression ratio mentioned above, the expansion ratio...

AI Technical Summary

Problems solved by technology

[0004] However, the disadvantages of the above-mentioned prior art are that since a supercharging device or a phase angle variable device must be provided, the structure of the internal combustion engine becomes complicated, the number of parts increases, and the cost and weight of the internal combustion engine also increase. up

In addition, unfortunately, in the prior art disclosed in the above publication, since the internal combustion engine operates in the form of Otto cycle at high load, the improvement of fuel consumption rate through the Miller cycle is not complete.

Images