High-pressure fuel supply system of internal combustion engine

A high-pressure fuel supply system of an internal combustion engine including a plurality of cylinders, comprising:

• a high-pressure pump driven by the internal combustion engine and operable with a cycle consisting of an intake stroke for receiving a fuel and a discharge stroke for delivering the fuel, the high-pressure pump comprising a valve selectively placed in an open position to allow the fuel to be introduced into the high-pressure pump and in a closed position to allow the fuel to be fed under pressure to a high-pressure portion of the fuel supply system that is located downstream of the high-pressure pump;
• and
• a controller that:
• generates commands for closing the valve to the high-pressure pump during starting of the engine before the cylinders are discriminated from each other, such that a period of the generated commands is shorter than a half of the cycle of operation of the high-pressure pump during starting of the engine;
• and
• after starting of the engine, controls a duration of closing of the valve during the discharge stroke of the high-pressure pump so that a regulated amount of the fuel is fed under pressure to the high-pressure portion of the fuel supply system
• wherein the valve is constantly biased under a first force in a valve-opening direction, and is moved by a second force in a valve-closing direction in response to the commands, and
• wherein a magnitude of the second force is determined so that the valve can be closed by the second force against the first force during the discharge stroke of the high-pressure pump, but cannot be closed by the second force during the intake stroke of the high-pressure pump with the first force and a pressure difference on opposite sides of the valve being applied to the valve in a valve-opening direction.