System for detecting the operation of the throttle valve

A system for detecting the operation of a throttle valve of an internal combustion engine, comprising

• means comprising a transducer for converting a physical parameter with respect to the operation of the throttle valve into an output voltage,
• a pair of sample-and-hold circuits electrically operatively connected to said transducer, each of said sample-and-hold circuits comprises a gate means and a voltage holding means for holding a value of said output voltage of said transducer at a time when said gate means is actuated for an interval thereafter,
• sampling pulse generator means for producing a pair of sampling pulse trains with a 180 degree phase difference,
• said sampling pulse generator means being connected to said gate means of each said sample-and-hold circuits for actuating said gate means so as to operate said sample-and-hold circuits alternately via said pair of sampling pulse trains, respectively,
• an operational amplifier comparator means having a non-inverting input and an inverting input for providing a resulting voltage constituting a differential voltage between signals applied to said non-inverting input and said inverting input,
• relay contact means for connecting an output of each of said sample-and-hold circuits to said non-inverting input and said inverting input, respectively, and
• relay means for actuating said relay contact means in synchronism with actuation of said sample-and-hold circuits so that the respective outputs of both said sample-and-hold circuits are feedable alternately to both said inputs of said operational amplifier comparator means with a fixed polarity, whereby the resulting voltage of said operational amplifier comparator means represents the change of the output voltage of said transducer per time increment between sequential pulses of said pair of sampling pulse trains.

A system for detecting the operation of a throttle valve of an internal combustion engine, comprising

• means comprising a transducer for converting a physical parameter of the operation of the throttle valve into an electrical signal constituting an output voltage of the transducer,
• holding circuit means constituting a sample-and-hold circuit comprising a holding capacitor and a gate operatively connected to each other,
• a pulse generator means connected to said gate for producing a pulse train of pulses having a constant period for operating said gate so as to enable said sample-and-hold circuit to detect a value of the output voltage of said transducer at every pulse and to hold said value for said period, respectively, and
• an output circuit means connected to said sample-and-hold circuit for continuously producing from said value a voltage, respectively, corresponding to the respective change of said output voltage per said period.