Intelligent control of motor vehicle gas equipment

Claim 1

In a device for the control of a carburetor unit for a gaseous fuel, for an internal combustion engine, comprising a vaporizer/pressure regulator for the supply of gas at a pressure near the air pressure upstream of the carburetor unit, a venturi type mixing device for mixing the gas with combustion air sucked in by a said internal combustion engine, a connecting line for connecting the vaporizer/pressure regulator to said mixing device, a main throttle valve for the intake of combustion air to control the engine output, said main throttle valve being adapted to be coupled to an accelerator pedal and being situated upstream of said mixing device, and a regulating valve in said connecting line for regulating the quantity of gas supplied to the mixing device, said regulating valve being coupled to said main throttle valve; the improvement comprising a mixing air supply device in said connecting line between said vaporizer/pressure regulator and said regulating valve, said supply device comprising a further venturi and an annular channel having a throat through which said gas flows between said vaporizer/pressure regulator and said regulating valve, a mixing air supply pipe that supplies air to said air supply device, said further venturi sucking said mixing air into said annular channel, a mixing air regulating valve in said mixing air supply pipe, the first-mentioned regulating valve being so dimensioned as to be adapted to supply too rich a gas/air mixture to the engine, and correction means controlling the opening of said mixing air regulating valve to dilute said gas with mixing air, thereby to supply to the engine a leaner gas/air mixture.