Patent ID: 7073487

Claim:
A fuel pressure control apparatus for a multicylinder internal combustion engine in which fuel is injected into the internal combustion engine having M cylinders, said apparatus comprising: fuel injection valves arranged one for each of said cylinders; a fuel injection amount calculation section that calculates a fuel injection amount per cylinder to be injected into each of said cylinders; a fuel injection valve control section that determines the injection pulse width of each of said fuel injection valves based on said fuel injection amount thereby to set the drive timing for each of said fuel injection valves; a fuel rail that is connected in common with said fuel injection valves to store high pressure fuel; a high pressure fuel pump that has N fuel discharge strokes with respect to said fuel rail while a fuel injection stroke makes a round of said respective cylinders; a fuel discharge amount control valve that adjusts a fuel discharge amount from said high pressure fuel pump; an FF amount calculation section that calculates, as an FF amount, a feedforward amount in the fuel discharge amount of said high pressure fuel pump based on said fuel injection amount; and a fuel discharge amount control section that determines the fuel discharge amount of said high pressure fuel pump based on said FF amount and sets the drive timing of said fuel discharge amount control valve; wherein said FF amount calculation section uses said fuel injection amount multiplied by M/N as an FF amount in the fuel discharge amount of said high pressure fuel pump in three times while the fuel injection stroke makes a round of said respective cylinders.