Liquid fuel injection pumping apparatus

摘要

A liquid fuel injection pumping apparatus includes a plunger movable inwardly in a bore to deliver fuel, by the action of a roller and a cam. An adjustable stop ring is provided to limit the extent of outward movement by the plunger and hence the maximum amount of fuel which can be supplied to the associated engine. The ring is positioned by a piston upon which liquid under pressure can act. The liquid under pressure is supplied by a low pressure pump and is admitted to one end of a cylinder containing the piston through a restrictor. The pressure downstream of the restrictor is controlled by a valve which includes a valve member spring biased into contact with a seating against the action of the pressure downstream of the restrictor. The air pressure in the engine inlet manifold is applied to a diaphragm and the force developed assists the action of the spring biasing the valve member.