Control system for determining the quantity of intake air of an internal combustion engine

A control system for an engine having an intake air passage, comprising:

• means for generating a first signal, said first signal being generated in synchronism with two rotation signals generated individually during two periods set in each engine cycle;
• means disposed in the intake passage for generating heat in accordance with an electric current supplied thereto;
• means for detecting the temperature of air passing through the intake passage;
• means for establishing a reference temperature in accordance with the air temperature detected by the air temperature detecting means;
• means for comparing the temperature of the heat generating means with the reference temperature established by the reference temperature establishing means;
• means for generating a second signal starting with the first signal and ending with an output of the comparing means indicating that the reference temperature is reached by the temperature of the heat generating means in accordance with the temperature of said heat generating means;
• means for supplying the heat generating means with the electric current during the time period of the second signal;
• means for determining a correction coefficient as a function of first and second variables, said first variable being proportional to the time period of the second signal previously produced and said second variable being proportional to the time period of the second signal currently produced;
• means for determining the quantity of air passing through the intake air passage in proportion to the product of the correction coefficient and the sum of the first and second variables;
• and
• means for controlling the engine in accordance with the determined quantity of air.

A control system for an engine having an intake air passage, said system comprising:

• heat generating means disposed in the intake air passage of the engine and adapted to be supplied with a heating current;
• heating current supply means for controlling the heating current supplied to said heat generating means in accordance with the temperature of said heat generating means;
• first measuring means for measuring a first quantity of air in said intake air passage from the heating current supplied to said heat generating means when the air flows in a forward direction in said intake air passage;
• second measuring means for measuring a second quantity of air in said intake air passage from the heating current supplied to said heat generating means when the air flows in a backward direction in said intake air passage;
• correction determining means for determining a correction coefficient from said first and second quantities of air, said correction determining means including:
• means for determining a sum of the measured first quantity of air and the second quantity of air;
• means for determining a difference between the measured first quantity of air and the second quantity of air;
• means for determining said correction coefficient from a ratio between the determined sum and the determined difference;
• and means for storing the correction coefficient and reading the stored correction coefficient out in accordance with the determined ratio;
• quantity determining means for determining the quantity of air passing through said intake air passage from the measured first quantity of air, second quantity of air and the determined correction coefficient;
• and
• control means for controlling operation of said engine in accordance with the determined quantity of air.