Device for controlling the flow of a high-pressure pump in a common-rail fuel injection system of an internal combustion engine

The common rail (6) supplies a number of injectors (5) of the cylinders (3) of the engine (2), and is supplied by a constant-displacement high-pressure pump (7) in turn supplied by a low-pressure, variable-delivery, variable-pressure, motor-driven pump (11). The control device has an electronic control unit (31) for receiving signals indicating operating conditions of the engine (2); the suction side of the high-pressure pump (7) has a choke (41); and the control unit (31) controls the motor-driven pump (11) to vary the fuel pressure upstream from the choke (41) between a predetermined maximum value and a predetermined minimum value, so as to regulate the fuel intake of the high-pressure pump (7) within a predetermined range.