Fuel injection system for internal combustion engines

Claim 1

A fuel injection system for an internal combustion engine, comprising: a fuel injection pump including a pump housing having a wall and filled with fuel, pumping means for forcibly delivering the fuel within said pump housing to the engine, and control means associated with said pumping means for controlling an amount of fuel delivered by said pumping means to the engine; an accelerator pedal disposed to be depressed; a governor arranged within said pump housing and associated with said control means for regulating the amount of fuel delivered by said pumping means to the engine, in dependence on the rotational speed of the engine; a control lever shaft supported by said wall of said pump housing for angular movement about an axis thereof relative thereto, said control lever shaft extending through said wall of said pump housing and having one end located interiorly of said pump housing and another end located exteriorly thereof; governor spring means connected between said one end of said control lever shaft and said control means for transmitting the angular movement of said control lever shaft to said control means in a manner such that when said control lever shaft angularly moves in a first direction said control means decreases the amount of fuel delivered by said pumping means to the engine, and when said control lever shaft angularly moves in a second direction said control means increases the amount of fuel delivered by said pumping means to the engine at a rate corresponding to the speed of the angular movement of said control lever shaft; a control lever fixedly mounted on said another end of said control lever shaft for angular movement therewith in said first and second directions; a cancel lever freely fitted on said another end of said control lever shaft for angular movement relative thereto, said cancel lever being disposed to abut against said control lever on a leading side of said cancel lever with reference to the angular movement thereof in said first direction; cancel spring means connected between said control lever and said cancel lever and acting upon them to be angularly moved together; an accelerator rod connecting said accelerator pedal to said cancel lever for transmitting depressing movement of said accelerator pedal to said cancel lever to angularly move said cancel lever in said first and second directions; and a dash pot arranged exteriorly of said pump housing and associated with said control lever for applying a counteracting force to the angular movement of said control lever in said second direction against the force of said cancel spring means; the force of said cancel spring means being set such that when said accelerator pedal is depressed to angularly move said cancel lever at a speed lower a predetermined value, said cancel spring means is not substantially resiliently deformed by said counteracting force of said dash pot to allow said cancel lever and said control lever to be angularly moved together in said second direction, while when said accelerator pedal is depressed to angularly move said cancel lever at a speed higher than said predetermined value, said cancel spring means is resiliently deformed by said counteracting force of said dash pot to allow said control lever to be angularly moved in said second direction behind the angular movement of said cancel lever in said second direction to thereby reduce the rate of increase of the amount of fuel delivered by said pumping means to the engine through said control means.