PURPOSE: To appropriately control the action of a dash pot in an engine in which the feed-back control of idling engine speed is carried out with the use of the detected opening degree of a throttle valve, by providing such a subtractor for gradually decreasing the desired opening degree of the throttle valve in accordance with a load upon load reduction from the intermediate load condition.
CONSTITUTION: An actuator 4 comprising a motor 5 and gears 6a through 6d is provided to drive a throttle valve 2 in an intake-air passage 1 for controlling the idling engine speed. A control device 15 receives signals from an idling sensor 9, a throttle valve opening degree sensor 8, etc. and carries out feed-back control in accordance with the opening degree of the throttle valve under a fixed running condition upon idling. When a load reduction from the intermediate load condition is detected in accordance with a signal from a load sensor 21, a computing device carries out subtraction to gradually decrease the desired opening degree of the throttle valve in accordance with the load, and the throttle valve 12 is gradually closed in dependence upon the thus obtained output, thereby the action of a dash pot is controlled while the action of engine braking is ensured.
HASHIMOTO TOORU
NAKAO KENZOU
| JPS57124037A | 1982-08-02 |