Fuel injection pumping apparatus

摘要

A fuel injection pumping apparatus of the rotary distributor type includes a cam ring the angular setting of which can be adjusted to determine the timing of delivery of fuel. In order to adjust the setting of the cam ring first and second fluid pressure operable pistons are arranged in parallel side by side relationship and are each coupled to the cam ring by a radial arm. The first piston is subject to a speed dependent pressure generated within the apparatus to provide normal speed advance and the second piston under the control of a valve can be subjected to said pressure to give full advance when the associated engine is cold and up to a predetermined engine load.