Patent ID: 6067794
Filing Date: 2000-05-30
Classification: F02D

Abstract:
A system with double loop for richness control for internal combustion engines of the fuel-injection type controlled by an electronic computer and equipped with a catalytic converter which comprises:a first control loop comprising a first nonlinear sensor to deliver a first electrical signal representative of the proportion of one of the components of the exhaust gases of the engine at the inlet of the catalytic converter and a first correction circuit to process the said first electrical signal in such a way as to deliver to the computer a first signal for correction of the quantity of fuel injected,a second control loop comprising a second nonlinear sensor to deliver a second electrical signal representative of the proportion of one of the components of the exhaust gases exiting the said catalytic converter, and a second correction circuit to process the said second electrical signal in such a way as to deliver to the computer a second signal for correction of the quantity of fuel injected,characterized in that it additionally comprises, in the second control loop, a circuit for filtering the output signal of the second correction circuit and an adder circuit, to which there are applied the output signal of the second correction circuit and the output signal of the filter circuit.