Throttle valve position detecting apparatus

Claim 1

An apparatus for use with an internal combustion engine having first and second throttle valves located in series within an engine induction passage, said apparatus comprising: first sensor means associated with said first throttle valve for deriving a first sensor signal indicative of a position of said first throttle valve with respect to a reference position; second sensor means associated with said second throttle valve for deriving a second sensor signal indicative of a position of said second throttle valve with respect to a reference position; and a circuit connected to said first and second sensor means and including first means for detecting a first minimum value of said first sensor signal obtained when said first throttle valve is at a minimum position, second means for detecting a second minimum value of said second sensor signal obtained when said second throttle valve is at a minimum position, means for calculating a difference between said first and second minimum values, first means for correcting one of said first and second sensor signals in a direction zeroing said difference, and second means for correcting said one of said first and second sensor signals, corrected by said first correcting means, based upon a constant corresponding to a difference between said minimum positions of said first and second throttle valves.

Claim 2

An apparatus for use with an internal combustion engine having first and second throttle valves located in series within an engine induction passage, said apparatus comprising: first sensor means associated with said first throttle valve for deriving a first sensor signal indicative of a position of said first throttle valve with respect to a reference position; second sensor means associated with said second throttle valve for deriving a second sensor signal indicative of a position of said second throttle valve with respect to a reference position; and a circuit connected to said first and second sensor means and including first means for detecting a first minimum value of said first sensor signal obtained when said first throttle valve is at a minimum position, second means for detecting a second minimum value of said second sensor signal obtained when said second throttle valve is at a minimum position, means for calculating a difference between said first and second minimum values, first means for correcting one of said first and second sensor signals in a direction zeroing said difference, and second means for correcting said one of said first and second sensor signals, corrected by said first correcting means, based upon a constant corresponding to a difference between said minimum positions of said first and second throttle valves.

Claim 4

An apparatus for use with an internal combustion engine having first and second throttle valves located in series within an engine induction passage, said apparatus comprising: first sensor means associated with said first throttle valve for deriving a first sensor signal indicative of a position of said first throttle valve with respect to a reference position; second sensor means associated with said second throttle valve for deriving a second sensor signal indicative of a position of said second throttle valve with respect to a reference position, said second sensor signal having a value greater than a value of said first sensor signal for the same throttle position; and a circuit connected to said first and second sensor means and including first means for detecting a first minimum value of said first sensor signal obtained when said first throttle valve is at a minimum position, second means for detecting a second minimum value of said second sensor signal obtained when said second throttle valve is at a minimum position, means for calculating a difference of said second minimum value from said first minimum value, means for adding said difference to said second sensor signal to correct said second sensor signal to produce a corrected second sensor signal, and means for adding a constant to said corrected second sensor signal to further correct said corrected second sensor signal, said constant corresponding to a difference between said minimum positions of said first and second throttle valves.

Claim 5

An apparatus for use with an internal combustion engine having first and second throttle valves located in series within an engine induction passage, said apparatus comprising: first sensor means associated with said first throttle valve for deriving a first sensor signal indicative of a position of said first throttle valve with respect to a reference position; second sensor means associated with said second throttle valve for deriving a second sensor signal indicative of a position of said second throttle valve with respect to a reference position, said second sensor signal having a value greater than a value of said first sensor signal for the same throttle position; and a circuit connected to said first and second sensor means and including first means for detecting a first minimum value of said first sensor signal obtained when said first throttle valve is at a minimum position, second means for detecting a second minimum value of said second sensor signal obtained when said second throttle valve is at a minimum position, means for calculating a difference of said second minimum value from said first minimum value, means for adding said difference to said second sensor signal to correct said second sensor signal to produce a corrected second sensor signal, and means for adding a constant to said corrected second sensor signal to further correct said corrected second sensor signal, said constant corresponding to a difference between said minimum positions of said first and second throttle valves.