Patent ID: 7451742

Claim:
An internal combustion engine comprising: an engine housing having a plurality of cylinders therein; a common rail; a plurality of fuel injectors fluidly connected with said common rail and each associated with one of said cylinders; a pressurization device for said common rail which includes a housing having a plurality of intensifier pistons disposed at least partially therein, at least one fluid inlet, and at least one fluid outlet connected with said common rail, said plurality of intensifier pistons being configured to reciprocate within said housing; a source of pressurized actuation fluid for said intensifier pistons fluidly connected with said at least one fluid inlet, said source of pressurized actuation fluid having an adjustable flow output and said plurality of intensifier pistons having a reciprocation speed within said housing which is based at least in part on the adjustable flow output; an hydraulically actuated valve movable between a first position at which it fluidly connects said at least one fluid inlet with a first one of said intensifier pistons but not a second one of said intensifier pistons, and a second position at which it fluidly connects said at least one fluid inlet with the second one of said intensifier pistons but not the first one of said intensifier pistons; and a control device coupled with said source of pressurized actuation fluid and configured to control a fluid pressure in said common rail at least in part by varying the reciprocation speed of said plurality of intensifier pistons via adjusting the flow output of said source of pressurized actuation fluid.