| 摘要 |
PURPOSE: To prevent an increase in the negative pressure of a venting pipe when a lower opening is plugged so as to protect a filter by connecting a negative pressure valve to the venting pipe having a lower opening connected to the fuel vapor filter. CONSTITUTION: A fuel vapor filter 1 is connected to a fuel tank 2a via a conduit 2, and to an intake system 3a of a motive power machine via a conduit 3. In order to reuse the filtration material of the filter 1, a lower end of the filter 1 is connected to a venting pipe 4. A lower opening 5 of the venting pipe 4 is arranged in the road region of a vehicle. In this case, a negative pressure valve 8 is connected to the venting pipe 4 via a conduit 7 having a downward opening 8 in an upper portion. When the lower opening 5 is plugged so that the negative pressure generated by the intake system 3a is increased and acts upon the filter 1 and venting pipe 4, a negative pressure valve 6 is opened to connect the venting pipe 4 with atmosphere. |
