| 摘要 |
PURPOSE:To control vibration of an engine, in which an intake air recirculating device is provided to control a feed mixture amount and reduce a pumping loss at idle operation, by decreasing a reduction amount of the pumping loss when the engine causes its vibration to at least a prescribed level. CONSTITUTION:In a suction stroke, a mixture passes an intake passage 3 through a throttle valve 7, previously increased its opening, and is fed to a cylinder 1 through an intake valve 4 in an opening state. At this time, an intake air recirculating valve 11 is opened before closing of the intake valve 4 and closed at half timing of a compression stroke with time delay from close timing of the intake valve 4, then the mixture in the cylinder 1 is partially returned to the intake passage 3 through a recirculating passage 10. In the above condition, the engine increases its vibration to feed a signal from a vibration detector sensor 14 through a gate 16, if output is generated from a comparator circuit 18, an open-close valve 12 is closed by an actuator 20 to inhibit recirculation of the mixture. |
