Abstract: An apparatus for reliably and quickly detecting a fault in an exhaust system of an internal combustion engine, based on an output of an air/fuel ratio sensor mounted in the exhaust system. The apparatus includes: a control unit which provides a rich air/fuel ratio forcefully and continuously when detecting the presence or absence of a fault in the exhaust system; and a determining unit which determines that there is a fault in the exhaust system when the sensor mounted in the exhaust system does not produce an output that corresponds to the rich air/fuel ratio being provided under control of the control unit. The detection accuracy of the apparatus is enhanced by making provisions to perform the exhaust system fault detection when the engine is in an idling state in which the fluctuation in pressure is large and the effect of exhaust pipe leakage is most pronounced.

Abstract: An apparatus for reliably and quickly detecting a fault in an exhaust system of an internal combustion engine, based on an output of an air/fuel ratio sensor mounted in the exhaust system. The apparatus includes: a control unit which provides a rich air/fuel ratio forcefully and continuously when detecting the presence or absence of a fault in the exhaust system; and a determining unit which determines that there is a fault in the exhaust system when the sensor mounted in the exhaust system does not produce an output that corresponds to the rich air/fuel ratio being provided under control of the control unit. The detection accuracy of the apparatus is enhanced by making provisions to perform the exhaust system fault detection when the engine is in an idling state in which the fluctuation in pressure is large and the effect of exhaust pipe leakage is most pronounced.

Abstract: A fuel tank including a tank body, a fuel supply pipe mounted on the tank body, a first canister connected to the tank body through a first fuel vapor passage provided with a change-over control valve therein, and a second canister connected to the tank body through a second fuel vapor passage provided with a check valve therein. The change-over control valve is opened during supply of fuel through the fuel supply pipe and the check valve is opened when the pressure within the tank body exceeds a predetermined value. A first vapor leading opening of the first fuel vapor passage for the first canister is positioned lower than a second vapor leading opening of the second fuel vapor passage for the second canister.

Abstract: A fuel tank comprising a fuel inlet pipe. A fuel pump nozzle is inserted into the fuel inlet pipe. A throat portion having a venturi shaped cross-section is arranged in the fuel inlet pipe between the interior space of the fuel tank and the tip of the fuel pump nozzle inserted into the fuel inlet port. Fuel spouted from the fuel pump nozzle passes through the entire cross-section of the throat portion.

Abstract: A fuel tank including a tank body, a fuel supply pipe mounted on the tank body, and a canister connected to the tank body. The fuel supply pipe is provided with a closing valve therein, the canister is connected to the tank body through a first fuel vapor passage having a change-over control valve. The fuel injection pipe is further communicated with the tank body through a second fuel vapor passage. The change-over valve is interlocked to the closing valve so that the change-over valve opens the first fuel vapor passage along with opening of the closing valve when a fuel feed nozzle is inserted into the fuel injection pipe.

Abstract: Fuel filler conduit connected at one end with fuel reservoir for engine in automobile etc. has the free end exposed out of the body wall. When removing a cap engaging with said free end for fuel filling, fuel vapour therein is released in the atmosphere.The invention provides a lid normally closing conduit inlet and adapted to be open by tip end of fuel dispensing nozzle. Angular movement of the lid actuates a valve normally closing an outlet to be open so that fuel vapour in the conduit is supplied from the outlet through a pipe to the engine.

Abstract: A fuel tank comprising a fuel inlet pipe and a cap detachably attached to the fuel inlet of the fuel inlet pipe. A valve port interconnecting the interior of the fuel tank to a canister is formed in the fuel inlet pipe. A control valve controlling the opening operation of the valve port is arranged in the fuel inlet pipe. The control valve is normally closed. When the cap is slightly unscrewed, the control valve automatically opens, and the fuel vapor in the fuel tank is fed into the canister via the valve port.

Abstract: Disclosed is a device comprising a lid which is pivotally connected to the vehicle body and normally closes a recess formed on the vehicle body. A cap of the fuel inlet of a fuel tank is arranged in the recess. The interior of the fuel tank is connected to a canister via a normally closed control valve controlled in response to the pivotal movement of the lid. When the lid is opened, the control valve opens to connect the interior of the fuel tank to the canister.

Abstract: A fuel tank comprising a fuel inlet pipe and a cap detachably attached to the fuel inlet of the fuel inlet pipe. The fuel tank has a small chamber expanding downward from the bottom wall of the fuel tank. The fuel outlet of the fuel inlet pipe is open to the small chamber. A baffle member made of a porous material is fixed to the inner bottom wall of the small chamber.

Abstract: A fuel tank comprising a fuel inlet pipe and a cap detachably attached to the fuel inlet of the fuel inlet pipe. A valve port interconnecting the interior of the fuel tank to a canister is formed in the fuel inlet pipe. A control valve controlling the opening operation of the valve port is arranged in the fuel inlet pipe. The control valve is normally closed. When a fuel pump nozzle is inserted into the fuel inlet, the control valve automatically opens, and the fuel vapor in the fuel tank is fed into the canister via the valve port.

Abstract: A fuel tank comprising a fuel inlet pipe and a canister housing which surrounds the upper portion of the fuel inlet pipe. A valve body is arranged in the upper portion of the fuel inlet pipe. A fuel vapor passage continuously connected to the interior of the fuel tank is formed between the valve body and the upper portion of the fuel inlet pipe. The valve body has a valve portion cooperating with a cap. When the cap is screwed into the threaded bore formed in the canister housing, the valve body disconnects the fuel vapor passage from the canister housing. When the cap is unscrewed, the fuel vapor passage is connected to the canister housing.