Mikuni Corporation

Ryoji Ehara

Shogo Hashimoto

Hiroshi Mizui

Junichiro Takahashi

Tadashi Nichogi

In a fuel injection system, a fuel tank is disposed below an electronically controlled fuel injection apparatus. A fuel reservoir chamber for supplying fuel from the fuel tank is disposed above the electronically controlled fuel injection apparatus, and the fuel stored in the fuel reservoir chamber is supplied to the electronically controlled fuel injection apparatus via a fuel supply passage. The fuel reservoir chamber and the fuel tank are connected by a first fuel return passage through which vapor is ejected and fuel in the fuel reservoir chamber overflows. A second fuel return passage for returning surplus fuel from the electronically controlled fuel injection apparatus is connected to either of the fuel reservoir chamber and the first fuel return passage at the position above the connecting position at which the fuel reservoir chamber connects with the first fuel return passage.

Fuel injection system

With structure comprising a cylinder, a magnetic circuit to exert a mountain-shaped thrust, and a feeding spring to exert an urging force to a plunger during a feeding process, fuel is sucked by movement of the plunger and energy is accumulated in the feeding spring during a powering state, the fuel is fed by movement of the plunger by the urging force of the feeding spring during a non-powering state, a spring constant of the feeding spring is set to generate an urging force larger than a thrust in an early range of the mountain-shaped thrust, and a second spring is disposed to exert an urging force in a direction against the urging force of the feeding spring to make the urging force smaller than the thrust, at least in the early range. In this manner, with an electromagnetically driven type plunger pump of a non-powering feeding type, an effective stroke is enlarged and a feeding amount is increased.

Electromagnetic drive type plunger pump

The present device is a fuel supply device to pressurize and supply fuel F which is stored in a fuel tankwhich comprises a fuel supply pipewhich forms a supply passage for the fuel F, a fuel filterto filter the fuel F disposed at the midway of the fuel pipeand below the fuel tanka fuel pumpto pressure-feed the fuel F disposed at the downstream side than the fuel filter, and a venting pipeto connect the downstream side of the fuel filterand an upper air-space A of the fuel tankThe object is to provide the fuel supply device and the fuel filter utilized for the fuel supply device which can ensure the discharging amount of the fuel pump by satisfactory removing of vapor which is generated in the fuel sucked to the fuel pump.

Fuel feeding device and fuel filter used for the device

An internal combustion engine fuel supply system includes a fuel discharge apparatus having a vapor removal system. The fuel discharge apparatus includes an apparatus body, a fuel chamber defined in the body, a fuel inlet connected to a fuel tank, a fuel supply path partially defined by the fuel inlet and connecting the fuel chamber to the fuel tank, a fuel discharge outlet, a fuel return outlet for return of excess fuel to the fuel tank, and a reflux path connecting the fuel supply path to the fuel return outlet. A vapor blocking member is provided in the fuel supply path at a bifurcation point at which the reflux path branches from the fuel supply path. The reflux path is arranged such that vapor blocked by the vapor blocking member rises from the bifurcation point and through the reflux path to the fuel return outlet due to self-buoyancy of the vapor.

Fuel discharge apparatus having a vapor removal system, and internal combustion engine fuel supply system having such fuel discharge apparatus

An electronically controlled fuel injection device includes a plunger pump constituted by a cylinder, a plunger is slidably mounted within the cylinder to form a pressure chamber, and a solenoid coil for driving the plunger. At a lower section of a body that encases the plunger pump, an intake section is coupled to the pressure chamber to cause intake of fuel into the pressure chamber upon operation of the plunger. At an upper section of the body, a return section is arranged to return surplus fuel to a fuel tank. A circulation passage branches off from the intake section and is provided between the cylinder and the solenoid coil for guiding a portion of the fuel toward the return section. With this arrangement, penetration of vapor into the fuel injection device is suppressed, and an inexpensive and highly durable electronically controlled fuel injection device is provided.

Electronically controlled fuel injection device

An electronically controlled fuel injection device includes a plunger pump, a circulation passage which circulates fuel that has been pressurized in the initial stage of a pressure-feeding stroke, a valve body which blocks the circulation passage in the later stage of the pressure-feeding stroke, an inlet orifice nozzle which allows the passage of fuel whose pressure has been increased in the later stage of the pressure-feeding stroke, an outlet orifice nozzle which is used to circulate some of the fuel that has passed through the inlet orifice nozzle back into the fuel tank, an injection nozzle which injects an amount of fuel equal to the difference between the fuel that has passed through the inlet orifice nozzle and the fuel that has passed through the outlet orifice nozzle, and a control arrangement for controlling the plunger pump in response to the cycle of the engine.

Growing community of inventors

Odawara, Japan

Ryoji Ehara