Multi-cylinder internal combustion engine

摘要

In a multi-cylinder internal combustion engine having a plurality of cylinders which are supplied with air via one common throttle valve and a control unit for regulating the number of operating cylinders to rest an arbitrary number of cylinders by blocking the air supply to said cylinders, the output of the engine under Z1-cylinder operation is known to come to coincide with the output under Z2-cylinder operation at one point with the same degree of opening of the throttle valve under a given constant rate of the engine rotation. At such a point, the pressure of the intake manifold under both the Z1-cylinder operation and the Z2-cylinder operation remain at or close to a certain value respectively over a wider range of rotation of the engine. This multi-cylinder internal combustion engine enables smooth switching between the Z1-cylinder operation and the Z2-cylinder operation without causing fluctuation in output nor shock by detecting the pressure at the intake manifold and the control unit for such switching can be made simple in construction.