| 摘要 |
PURPOSE:To prevent the erroneous operation of a choke due to variations in negative pressure of an intake-air pipe upon engine operation, by providing a valve which is closed when the vehicle speed is higher than a predetermined speed, in a negative pressure passage controlled by a choke valve that is opened by negative pressure effected under complete explosion. CONSTITUTION:A choke valve 3 in a carburetter 1 is opened when negative pressure in an intake-air pipe is introduced into a diaphragm chamber 6 through a pipe 5 and a constriction 12 upon complete explosion of an engine. Meanwhile, when both of a cranking signal 9 indicating the complete explosion of the engine and a signal 10 indicating the vehicle speed higher than a predetermined value are effected, a coil 8a is energized so that a valve 8 closes the pipe 5. With this arrangement there may be prevented such an erroneous operation that the choke is closed due to a decrease in negative pressure upon acceleration during operation of the engine, and as well such an erroneous operation that the choke is opened due to an increase in negative pressure upon deceleration next to the acceleration. The control may be made by a signal 11 indicating the vehicle speed or engine rotational speed. |
