| 摘要 |
PURPOSE:To prevent knocking due to the delay of control on the lowering of compression ratios by using a system in which when acceleration is made by quickly opening a throttle valve, angular velocity retardation control is made during the ignition period in an interlocking manner with the acceleration in an internal combustion engine in which reciprocal movement is made by an oil pressure according to load of the engine for a subpiston inside a subcylinder. CONSTITUTION:An ignition time control circuit 31 has a function by which angular velocity retardation control is made for a proper period of time by a proper angle in the angular velocity retardation direction on the basis of output signals from a throttle valve opening speed detection circuit 32 with respect to ignition time. When the opening speed of the throttle valve 9 exceeds apreset value by the step-in operation of accel pedal, since the ignition time is properly subjected to an angular velocity retardation control in the direction of angular velocity retardation only for a proper period of time, the occurrence of knocking due to the delay of retraction of subpiston 13 in the early period of the acceleration of engine is suppressed, and at a time when the subpiston 13 goes back to a given position beyond a proper period of time from the acceleration of the engine, the angular velocity retardation control of the ignition time is released. |
