Air-fuel ratio controller for operating cylinder number variable type internal-combustion engine

Abstract

Abstract PURPOSE:To reduce a torque variation in time of cylinder number selection, by operating an engine in a way of dividing a degree of throttle valve opening, from small to large, into a partial cylinder running range, a partial stoichiometric running range, an all-cylinder lean running range and an all-cylinder stoichiometric running range. CONSTITUTION:When being applied to a 4-cylinder engine, there is provided with a driving condition detecting device 4 inclusive of an opening detecting device 4a outputting a signal corresponding to the opening of a throttle valve 3, and the output signal is inputted into a controlling device 5 outputting a driving signal to injectors 2-1-2-4. The controlling device 5 is constituted of installing an operating cylinder number setting part 5a determining the number of cylinders to be operated in making the specified opening value of the throttle valve 3 a criterion and an air-fuel ratio setting part 5b setting such a value as having a trend which makes an air-fuel ratio smaller over the range from small to large of the throttle opening. And, engine operation should be done in a way of dividing the throttle valve opening into a partial cylinder lean running range, a partial cylinder stoichiometric running range, an all- cylinder lean running range and an all-cylinder stoichiometric running range.

Inventors

• 👤 Toshimi Kashiwakura
• 👤 利美 柏倉

Bibliographic Details