| 摘要 |
PURPOSE:To change the number of working cylinders in a wide range of operation without deteriorating the operation performance, by providing a throttle opening degree characteristic alteration means in a throttle valve drive unit and shifting the means in response to a control signal from an idle cylinder control signal from an idle cylinder control means to cause all the cylinders to work or put some cylinders out of operation. CONSTITUTION:The atmospheric pressure or negative intake pressure is selectively conducted to the chamber 11 of an actuator 9 through an electromagnetic changeover valve 12 to which a control signal S2 is applied from an idle cylinder control circuit 1 depending on the operating condition of an engine. The control signal S2 is applied to shift the three-way changeover valve 12 to conduct the atmospheric pressure to the chamber 11 to cause all cylinders to work or conduct the negative intake pressure to the chamber to put some cylinders out of operation. Following the shifiting of the valve 12, the degree of opening of a throttle valve is altered without changing the depression of the accelerator pedal, to eliminate the torque difference of an output shaft at the time of the shifting to reduce the shifting shock in a wide range of operation. |
