摘要 |
A system for regulating the injection of auxiliary air into the intake of internal combustion engines includes a pressure-regulating stage feeding an intermediate compartment with an intermediate pressure proportional to that in the engine's intake manifold, and an opening-regulating stage through which air flows from the intermediate compartment toward the intake chamber communicating with the manifold. The opening-regulating stage includes a metering valve activated by a membrane which is controlled by a control pressure obtained by joining a compartment on one side of the membrane to intake pressure through a conduit having a metering orifice or choke thereon and also joining the compartment to an intermediate compartment through an electrically-activated valve the opening of which is controlled by a current at the frequency of the engine. The variable opening time of the electrically-activated valve is determined as a function of the engine frequency and the output from an overlying probe in the engine exhaust. |