| 摘要 |
PURPOSE:To prevent evaporation of fuel by utilizing the latent heat evaporation of fuel by allowing the fuel vapor in a float chamber to be adsorbed onto a canister when an engine is in stop and carrying-out purging of the canister through the float chamber when the engine starts. CONSTITUTION:A negative-pressure generating throttle part 16 is installed closely to an air cleaner 15 in an air passage 14 on the upstream side of venturis 7 and 8, and said throttle part 16 is communicated with the space above the oil surface in a float chamber 3 through a vent pipe 17. Midway on the vent pipe 17, an ON/OFF valve 18 which is opened only when the engine operates, interlocked with an ignition switch. When the engine operates, intake operation is performed into the air passage 14 from a canister 13 side by the pressure difference between the negative pressure in the throttle part 16 and the atmospheric pressure on the canister side, and air is allowed to flow in the float chamber 3, and the temperature of the fuel surface is directly reduced in form of the fuel evaporation heat. |
