Control system of evaporated fuel

Claim 1

An evaporated fuel control system comprising: an engine mounted on a vehicle; a fuel tank mounted on the vehicle to supply fuel to the engine, the fuel tank having a fuel injection port to receive a filler gun for fuel supply and an exhaust port to discharge evaporated fuel in the tank; a first evaporator line connected to the exhaust port of the fuel tank to introduce the evaporated fuel in the fuel tank into the engine; a seal means provided to the fuel injection port to prevent the evaporated fuel from leaking out through the fuel injection port when the filler gun is inserted into the fuel injection port; a filler switch to detect a filler gun insertion signal when the filler gun is inserted into the fuel injection port of the fuel tank; a first canister disposed in the first evaporator line to temporarily hold and adsorb the evaporated fuel from the fuel tank; a first solenoid valve provided in the first evaporator line between the fuel tank and the first canister; a second solenoid valve provided in the first evaporator line between the first canister and the engine; a third evaporator line to open the first canister into the open air through a filter, the filter being installed in the canister for adsorbing the vapor fuel; a third solenoid valve provided in the third evaporator line; a second evaporator line connected to the exhaust port of the fuel tank to introduce evaporated fuel in the fuel tank into the engine; a second canister provided in the second evaporator line to temporarily hold and adsorb the evaporated fuel from the fuel tank, the second canister being communicated with the engine; and a control means to open the first solenoid valve, while the engine is stopped, to communicate the first canister with the fuel tank in response to the detection signal from the filler switch that detects when the filler gun is inserted into the fuel injection port and at the same time open the third solenoid valve to communicate the first canister to the open air through the filter, the control means also being adapted to open the second solenoid valve, while the engine is running, in response to the state that the evaporated fuel can be purged into the engine, to communicate the first canister with the engine, and at the same time open the third solenoid valve to communicate the first canister to the open air through the filter.