FUEL EVAPORATIVE EMISSION PROCESSING SYSTEM

摘要

A fuel evaporative emission processing system suitable for a hybrid vehicle includes a fuel vapor passage, a shut-off valve, a purge passage, a first purge control valve, and a second purge control valve. The shut-off valve selectively opens and closes the fuel vapor passage communicating between a fuel tank and a canister. The first purge control valve opens and closes the purge passage communicating between the canister and an intake air passage of an internal combustion engine. The second purge control valve selectively opens or closes the tank opening passage communicating between the purge passage on an upstream side of the first purge control valve and the fuel tank. When purging the canister, by opening the second purge control valve, the evaporative fuel inside the fuel tank is directly processed by the internal combustion engine, so that increase in the amount of adsorption in the canister can be suppressed.

主权项

1. A fuel evaporative emission processing system for an internal combustion engine, comprising:
a fuel vapor passage communicating a fuel tank and a canister; a shut-off valve interposed in the fuel vapor passage and configured to selectively open and close the fuel vapor passage, a purge passage communicating the canister and an intake passage of the internal combustion engine; a first purge control valve interposed in the purge passage and configured to selectively open and close the purge passage; a tank opening passage communicating the purge passage in an upstream side position of the first purge control valve and the fuel tank; a second purge control valve interposed in the tank opening passage and configured to selectively open and close the tank opening passage; and a purge control mechanism configured to purge the canister by controlling the first purge control valve during operation of the internal combustion engine, wherein the purge control mechanism is configured to process the evaporative fuel emission in the fuel tank by the internal combustion engine by opening the second purge control valve during purging of the canister.