Fuel injection pumping apparatus for internal combustion engines

Claim 1

A fuel injection pumping apparatus for supplying fuel to internal combustion engines comprising an injection pump for delivering fuel in timed relationship to an associated engine, a feed pump for supplying fuel to the injection pump during the filling periods thereof, throttle means for adjusting the amount of fuel supplied by the feed pump to the injection pump and fluid pressure operable means for adjusting a component of the injection pump to vary the timing of delivery of fuel to the associated engine, valve means operable to provide a fluid pressure which increases as the speed of operation of the apparatus increases, a first fixed orifice through which said fluid pressure is applied to said fluid pressure operable means, a second fixed orifice and through which fluid from the down stream side of said first fixed orifice can flow to a drain, a variable orifice connected in series with said second orifice and operable to vary the speed responsive pressure applied to the fluid pressure operable means, the size of said variable orifice being determined by the setting of said throttle means, and a pressure responsive valve operable to provide a flow path in parallel with one of said orifices, said valve being responsive to a fluid pressure within the system.