Non-linear position transducer for detecting the position of a valve controlling the rate of flow of air inducted to the cylinders of a heat engine

Claim 1

A non-linear position transducer (1) for detecting the position of a valve (7) for controlling the rate of flow of air inducted to the cylinders of a heat engine (9), comprising first means (5) for detecting the position (α) of the said valve (7) and second means (3,4) coupled to the said first means (5) and operable to provide an electric output signal (V 2 ) in non-linear relation to the position (α) of the said valve (7), characterised by the fact that the said first and second means (3,4,5) comprise an electrical sensing circuit, said sensing circuit further comprising a first and second resistor connected in parallel with each other and forming a first resistor pair, a first end of said resistor pair being connected to a voltage level, a third and fourth resistor connected in parallel with each other and forming a second resistor pair, a first end of said second resistor pair being connected to a second voltage level different from said first voltage level, the other ends of said resistor pairs being electrically connected together, said electrical output signal being present at said other ends of said resistor pairs, wherein said second means comprises means for varying the resistive values of the first and third resistors inversely with respect to each other as a function of the valve position and wherein said sensing circuit is constructed wholly from passive components.