Patent ID: 8646748

Claim:
A gaseous fuel regulator for supplying pressure regulated gaseous fuel from a fuel tank to a fuel dosing device, comprising (a) a housing; (b) a regulation chamber arranged in said housing; (c) a piston arranged in said regulation chamber in a loose fit configuration to define a first chamber and a second chamber within said regulation chamber on opposite sides of said piston and an annular passage between said piston and a side wall of said regulation chamber, said first chamber including a first inlet and said second chamber including a second inlet for delivering gaseous fuel to said first and second chambers, respectively, from the fuel tank at an inlet pressure, said first chamber including a first outlet and said second chamber including a second outlet connected with an outlet conduit for delivering said gaseous fuel at an outlet pressure to the dosing device, said piston having a first surface facing said first outlet and a second surface facing said second outlet, said first surface having a planar configuration and said second surface having a configuration tapering toward said second outlet, said piston being displaced within said regulation chamber in response to a change in pressure of said gaseous fuel in said first chamber to open and close said second outlet from said second chamber to change said outlet pressure, said passage allowing a flow of said gaseous fuel between said first chamber and said second chamber; (d) a control chamber arranged in said housing and connected with said first chamber via said first outlet; (e) a valve mechanism arranged in said housing and including a solenoid valve comprising a shutter arranged in said control chamber for opening and closing said first outlet from said first chamber to change the pressure of said gaseous fuel in said first chamber; (f) a bypass conduit connecting said control chamber with said outlet conduit; (g) a pressure sensor connected with said outlet conduit for measuring said outlet pressure; and (h) a control device connected with said pressure sensor and with said valve mechanism, said control device comparing said outlet pressure with a set pressure and generating an electric signal when said outlet pressure deviates from said set pressure to operate said valve mechanism by way of pulse width modulation cycles to open and close said first outlet in order to vary the pressure within said first chamber, thereby to operate said piston to bring the outlet pressure to the set pressure.