| 摘要 |
PROBLEM TO BE SOLVED: To provide an evaporated fuel treatment device not impairing desorption efficiency in desorbing an evaporated fuel by utilizing only intake pipe negative pressure while stopping a purge pump.SOLUTION: An evaporated fuel treatment device includes a fuel tank 1, a canister 2, an atmosphere passage 10, a vapor passage 11, an intake pipe 15, a purge passage 12, a purge pump 3, and a flow rate control valve 4. In a case when a negative pressure is sufficiently generated in the intake pipe 15, an evaporated fuel is desorbed only by the negative pressure of the intake pipe. When the negative pressure is not sufficiently generated in the intake pipe 15, the purge pump 3 is driven to desorb the evaporated fuel. The purge pump 3 and the flow rate control valve 4 are disposed on the purge passage 12. The purge pump 3 is a vortex pump in which a gas can pass even in stopping its drive. A minimum cross-sectional area of an internal space in the purge pump 3 is a minimum cross-sectional area of an internal space of the purge passage or more.SELECTED DRAWING: Figure 1 |
