INTAKE SYSTEM EVAPORATIVE FUEL LEAKAGE PREVENTING DEVICE

摘要

PROBLEM TO BE SOLVED: To improve the reliability of an intake system evaporative fuel leakage preventing device. SOLUTION: A housing 10a of an air cleaner 10 in an intake passage 7 is internally equipped with an on-off valve 30 closable by a given set point or lower of an intake flow rate passing the intake passage to close a connection opening 10b in the housing into an air intake nozzle 17. During an engine stop, the on-off valve is closed to close the connection opening 10b and thus prevent emission of fuel vapor generated in the intake passage from the nozzle 17 to the atmosphere. The on-off valve 30 has a valve element 30a of a flat plate shape, and closes the opening 10b through surface contact with the periphery of the connection opening 10b. The vale element is thus protected against a malfunction due to entrainment of foreign matter and the like in valve element closing.