Apparatus and system for controlling the air-fuel ratio supplied to a combustion engine

A carburetor for a combustion engine, comprising carburetor body means, induction passage means formed in said body means, variably positionable throttle valve means for controlling the rate of motive fluid through said induction passage means and into said engine, fuel reservoir chamber means formed in said body means, idle fuel metering system means communicating generally between said fuel reservoir chamber means and said induction passage means, main fuel metering system means communicating generally between said fuel reservoir chamber means and said induction passage means for supplying rates of metered main fuel flow throughout the entire range of required rate of metered main fuel flow, said main fuel metering system means comprising modulating valve means carried by said body means and effective to be variably positioned in order to thereby controllably alter the rate of metered main fuel flow through said main fuel metering system means to said induction passage means, and electrically energizable motor means carried by said body means and operatively connected to said modulating valve means, said electrically energizable motor means being continuously effective throughout said entire range of required rates of metered main fuel flow to continuously variably position said modulating valve means in response to the electrical energization experienced by said electrically energizable motor means, said modulating valve means comprising first orifice means and a valve member cooperating with said first orifice means to variably define therebetween an effective fuel metering area, said main fuel metering system means further comprising calibrated second orifice means, said first and second orifice means being in parallel fluid circuit relationship to each other, said main fuel metering system means further comprising calibrated third orifice means, and said third orifice means being in series fluid circuit relationship with said first orifice means and in parallel circuit relationship with said second orifice means.

A carburetor for a combustion engine, comprising carburetor body means, induction passage means formed in said body means, variably positionable throttle valve means for controlling the rate of motive fluid through said induction passage means and into said engine, fuel reservoir chamber means formed in said body means, main fuel metering system means communicating generally between said fuel reservoir chamber means and said induction passage means for supplying rates of metered main fuel flow throughout the entire range of required rate of metered main fuel flow, said main fuel metering system means comprising modulating valve means carried by said body means and effective to be variably positioned in order to thereby controllably alter the rate of metered main fuel flow through said main fuel metering system means to said induction passage means, and electrically energizable motor means carried by said body means and operatively connected to said modulating valve means, said electrically energizable motor means being continuously effective throughout said entire range of required rates of metered main fuel flow to continuously variably position said modulating valve means in response to the electrical energization experienced by said electrically energizable motor means, said modulating valve means comprising first orifice means and a valve member cooperating with said first orifice means to variably define therebetween an effective fuel metering area, said main fuel metering system means further comprising calibrated second orifice means, said first and second orifice means being in parallel fluid circuit relationship to each other, said main fuel metering system means further comprising calibrated third orifice means, and said third orifice means being in series fluid circuit relationship with said first orifice means and in parallel circuit relationship with said second orifice means.

A carburetor for a combustion engine, comprising carburetor body means, induction passage means formed in said body means, variably positionable throttle valve means for controlling the rate of motive fluid through said induction passage means and into said engine, fuel reservoir chamber means formed in said body means, main fuel metering system means communicating generally between said fuel reservoir chamber means and said induction passage means, additional fuel metering system means communicating generally between said fuel reservoir chamber means and said induction passage means, said main fuel metering system means comprising first modulating valve means carried by said body means and effective to be variably positioned in order to thereby controllably alter the rate of metered main fuel flow through said main fuel metering system means to said induction passage means, said additional fuel metering system means comprising second modulating valve means carried by said body means and effective to be variably positioned in order to thereby controllably alter the rate of metered additional fuel flow through said additional fuel metering system means to said induction passage means, first electrically energizable motor means carried by said body means and operatively connected to said first modulating valve means, said first electrically energizable motor means being effective to variably position said first modulating valve means in response to the electrical energization experienced by said first electrically energizable motor means, and second electrically energizable motor means carried by said body means and operatively connected to said second modulating valve means, said second electrically energizable motor means being effective to variably position said second modulating valve means in response to the electrical energization experienced by said second electrically energizable motor means.