Patent ID: 8132561

Claim:
A gas-feed system, for feeding methane or hydrogen to an internal-combustion engine, the system comprising: a plurality of electromagnetically controlled injectors coupled to the various cylinders of the engine; a distribution manifold or rail communicating with said injectors; a tank for supplying gas to the distribution manifold where pressurized gas is accumulated; and a pressure-reducing valve set in a connection between the tank and said distribution manifold, wherein said pressure-reducing valve comprises: an inlet connected to the tank and an outlet connected to the distribution manifold, as well as an auxiliary inlet; and valve means configured to determine a reduction in pressure of the gas in the passage from said inlet to said outlet, said pressure reduction being dependent upon a pressure signal sent to said auxiliary inlet, a modulating solenoid valve for sending said pressure signal to said auxiliary inlet, said modulating solenoid valve comprising: an inlet communicating with the fuel tank; an outlet communicating with the auxiliary inlet of the pressure-reducing valve, as well as with the distribution manifold; a solenoid for control of a mobile anchor that controls communication between the inlet and the outlet of the modulating solenoid valve so as to bring about a predetermined reduction in pressure of the gas in the passage from the inlet to the outlet of the modulating solenoid valve, electronic means for control of the solenoid of said modulating solenoid valve; and wherein the pressure-reducing valve and the modulating solenoid valve are integrated in a body of a single electronic pressure-reducer or pressure-regulator unit, said body comprising: the inlet for the gas coming from the fuel tank; the outlet for the gas that is supplied to the distribution manifold or rail; a passage for communication between the inlet and the pressure-reducing valve; a passage for communication between the inlet and the modulating solenoid valve; a passage for communication between the modulating solenoid valve and the pressure-reducing valve; a passage for communication between the modulating solenoid valve and the outlet; and a passage for communication between the pressure-reducing valve and the outlet, said unit further incorporating an electronic control module for controlling the solenoid of the modulating solenoid valve, said electronic control module comprising electronic means for comparing a signal indicating the effective pressure existing in the distribution manifold or rail with a pressure reference signal and for controlling, on the basis of said comparison according to a closed-loop logic, the solenoid of the modulating solenoid valve; said body of said unit further comprising a passage for direct fluid communication of the outlet of the modulating solenoid valve with the distribution manifold or rail, said passage for communication comprising a restricted section defined by a hole of predetermined dimensions.