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: An apparatus for preventing the outflow of a fuel from a fuel tank for vehicle comprises a vent tube device connected to the fuel tank and a canister device connected to the inlet system of an engine to supply the fuel into the tank, an evaporating tube device separated from the vent tube device and connected to the fuel tank and the canister device to supply the evaporated fuel within the tank to the canister device, a shut-off valve disposed in the vent tube device to pass and interrupt the fuel flow through the vent tube device, an opener switch for detecting the opening and closing states of a lid opener opening and closing a filler lid for supplying the fuel into the fuel tank, and a control device for controlling the opening and closing of the shut-off valve by the opener switch to open the shut-off valve only in the open state of the lid opener.

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.

Abstract: A device liquefies fuel vapor generated in a fuel tank. An arrangement prevents the liquefied fuel from escaping into the atmosphere. The liquefied fuel may be returned to the fuel tank. A canister may be used to trap fuel vapor which is not liquefied by the device.

Abstract: A fuel supply port structure of a fuel tank for use in vehicles comprises a filler tube with a neck portion and a fuel supply gun guide disposed within the filler tube. The fuel supply gun guide has an opening at the lower end thereof to receive a fuel gun inserted therethrough. The fuel supply gun guide also has a shutter plate pivotally connected so as to usually close the opening. The shutter plate pushed by the fuel gun inserted opens the opening, wherein the shutter plate has raised at the central portion thereof with which the fuel gun comes into contact, so that even if the fuel gun is insufficiently inserted, the free end portion of the shutter plate clears the flow of the fuel emanating from the fuel supply gun.

Abstract: A filter device for use in a fuel tank, has a filter body having an upper wall and a lower wall, a guide portion extending through the filter body and having an intake hole at a lower portion of the guide portion near the bottom wall of the filter body, a suction pipe having a lower portion which is inserted into the guide portion, and spring means provided between the suction pipe and the filter body for biasing the filter body toward the bottom wall of the tank body.

Abstract: A fuel filter device for use in a fuel tank, comprising an upper blank plate, a lower blank plate, a filter body having a filter portion fixed between the upper and lower blank plates, and at least one fuel suction pipe having a lower portion which is placed in the filter body, a fuel suction port being formed in a lower end portion of the fuel suction pipe characterized by the filter portion being flexible, the lower portion of the fuel suction pipe being foldable.

Abstract: A sensor detects the flow rate of fuel returned from an internal combustion engine to a fuel tank to control a pump motor in such a manner that an appropriate amount of fuel is supplied from the pump to the engine.

Abstract: A pressure control device with a fluid discharge prevention mechanism such that operation is reliable, size is small, weight is light, and cost is low. The pressure control device according to the present invention comprises a novel valve body housing a weight and a fluid discharge prevention valve together, a vessel body with a tank-communicating port, and a lid with an atmosphere-communicating port. The top circumferential surface of the valve body serves also as a vacuum pressure regulation valve in cooperation with the vessel body.

Abstract: A device for pumping fluid includes a main pump device and an auxiliary device integrally fixed thereto. The auxiliary device can function as a damper, cut-off valve, check valve and relief valve. The auxiliary device includes a first and second room separated by a diaphragm. The first room is connected to the fuel supply passage of the main pump device. One end of the outlet passage of the auxiliary device is connected to the first room by way of a valve mechanism consisting of a valve body and valve seat. The valve body is actuated by deforming of the diaphragm in response to the change of the fluid pressure within the first room. A relief passage is formed in the valve body to connect the first room with the second room. A relief valve such as a ball valve is placed in cooperation with the relief passage.

Abstract: A safety valve which interrupts fluid flow when it is substantially tilted or inverted, comprises a valve chamber with three lobes two of which have an inlet and an outlet opening at an inlet and an outlet valve seat, respectively. A ball is freely movable within the chamber. When the chamber is in its normal position, or preferred orientation, the ball rests or floats in the third lobe, but when the chamber is tilted or inverted, the ball moves into one of the other lobes and abuts against the inlet or the outlet valve seat.