Abstract: A valve for detecting a liquid surface used in a fuel tank is formed of a valve body having an orifice at an upper part thereof, a plurality of bottom through-holes formed at a bottom part thereof, and a plurality of surrounding wall through-holes formed at a surrounding part thereof; a valve member movably disposed inside the valve body to close the orifice; and an urging member for moving the valve member in cooperation with buoyancy of the valve member so as to close the orifice. In the valve of the invention, the diameter of the orifice is set to be larger than the diameter of the bottom through-holes, and also larger than a diameter of the surrounding wall through-holes. Therefore, the orifice can be prevented from being clogged by foreign substances.

Abstract: A float valve device for a fuel tank of an automotive vehicle. The float valve device comprises a valve body installed to an upper wall of the fuel tank. The valve body is formed thereinside with a communication passage for establishing communication between inside and outside of the fuel tank. A valve mouth member is fixedly disposed inside the communication passage and includes a lower end section having a peripheral portion defining thereinside a valve opening which forms part of the communication passage. A float is disposed inside the valve body and movable relative to the valve opening in accordance with a level of the liquid in the fuel tank. A rubber member is securely disposed at an upper section of the float. The rubber member has a sealing face which is substantially flat and contactable with the peripheral portion of the valve mouth member to close the valve opening upon ascending of the float.

Abstract: A fuel control system includes a valve assembly disposed between a fuel tank with a filler tube and a fuel vapor storage canister. The valve assembly includes a housing having a vapor inlet port for establishing communication with the fuel tank at a level above the full level of fuel contained in the fuel tank, and a vent inlet port for establishing communication with the fuel tank until the full level is reached by fuel contained in the fuel tank. An outlet port is provided for establishing communication with the canister. A conduit is provided for transmiting signal pressure for establishing communication with the filler tube at a level above the fuel level of fuel in the filler tube. First and second check valves are mounted within the housing and respectively include valve seats, valve elements, springs and diaphragms. The diaphragms cooperate with the housing to define a signal pressure chamber communicating with the conduit.

Abstract: A reservoir arrangement for use in an automotive fuel tank includes a reservoir body in which fuel is guided and from which fuel is pumped. The reservoir body defines a fuel passage by upwardly depressing its bottom surface and fittingly engaged the depressed surface with a chamber plate. The chamber plate is made of a material whose swelling amount by fuel is larger than that of the reservoir body, thereby causing a tight fit of the chamber plate.

Abstract: A fuel supply system including a fuel tank, a feed conduit through which fuel is pumped from the fuel tank, and a return conduit through which excess fuel is returned to the fuel tank. The fuel tank has first and second sumps. The system comprises an ejector pump having a pressure chamber opening through a throat into the first sump. The pressure chamber is connected through a communication conduit to the second sump. The ejector pump includes a fuel nozzle having an inlet port connected to the return conduit and a discharge end opening into the pressure chamber for discharging a jet of fuel into the pressure chamber to create a negative pressure in the pressure chamber so as to suck fuel through the communication conduit from the second sump. In one aspect of the invention, a relief valve is provided which is responsive to a back pressure produced in the fuel nozzle for relieving the back pressure to the first sump when the back pressure exceeds a predetermined value.

Abstract: A fuel-level detecting system for detecting residual fuel in a fuel tank includes two fuel-level detecting sensors, one of which is disposed within one chamber of the fuel tank, the other of which is disposed within the other chamber of the fuel tank. This system can more accurately detect actual fuel-level by indicating a value in accordance with current running through a closed circuit formed by the fuel-level detecting sensors and so forth.

Abstract: Herein disclosed is a fuel tank vent system which comprises a fuel tank of moulded plastics which is formed with a depressed portion protruding into a vapor chamber defined at an upper portion of the interior of the fuel tank, and a structure of moulded plastics which is incorporated with the depressed portion to define an enclosed chamber at the position above the maximum level of fuel in the fuel tank. A first piping or opening is provided for achieving a fluid communication between an upper portion of the enclosed chamber and an upper portion of the vapor chamber, and a second piping or tube is provided for achieving a fluid communication between a lower portion of the enclosed chamber and a lower portion of the vapor chamber.