Apparatus for controlling fuel delivery to engine

Claim 1

An apparatus for controlling a multi-cylinder type internal combustion engine including first and second cylinder groups each including at least one cylinder, comprising: sensor means for generating electrical signals indicative of engine operating conditions including engine speed; a control circuit coupled to said sensor means for calculating an appropriate value repetitively at uniform intervals, the calculation being made according to engine operating conditions; fuel supply means coupled to said control circuit for supplying fuel to said first and second cylinder groups in an amount corresponding to the calculated value; said control circuit including means responsive to an overspeed condition for operating said fuel supply means in a fuelcut mode to alternatively terminate fuel delivery to said first cylinder group and fuel delivery to said second cylinder group, means for calculating a difference of a predetermined fuelcut speed value from an existing engine speed, and means for determining the overspeed condition when the calculated difference is greater than zero, said control circuit including means for setting a value of a first interval during which said fuel supply means operates in the fuelcut mode according to the calculated difference.

Claim 2

An apparatus for controlling a multi-cylinder type internal combustion engine including first and second cylinder groups each including at least one cylinder, comprising: sensor means for generating electrical signals indicative of engine operating conditions including engine speed; a control circuit coupled to said sensor means for calculating an appropriate value repetitively at uniform intervals, the calculation being made according to engine operating conditions; fuel supply means coupled to said control circuit for supplying fuel to said first and second cylinder groups in an amount corresponding to the calculated value; said control circuit including means responsive to an overspeed condition for operating said fuel supply means in a fuelcut mode to alternatively terminate fuel delivery to said first cylinder group and fuel delivery to said second cylinder group, means for calculating a difference of a predetermined fuelcut speed value from an existing engine speed, and means for determining the overspeed condition when the calculated difference is greater than zero, said control circuit including means for setting a value of a first interval during which said fuel supply means operates in the fuelcut mode according to the calculated difference.

Claim 5

An apparatus for controlling a multi-cylinder type internal combustion engine including first and second cylinder groups each including at least one cylinder, comprising: sensor means for generating electrical signals indicative of engine operating conditions including engine speed; a control circuit coupled to said sensor means for calculating an appropriate value respectively at uniform intervals, the calculation being made according to engine operating conditions; fuel supply means coupled to said control circuit for supplying fuel to said first and second cylinder groups in an amount corresponding to the calculated value; said control circuit including means responsive to an overspeed condition for operating said fuel supply means in a fuelcut mode to alternatively terminate fuel delivery to said first cylinder group and fuel delivery to said second cylinder group, means for calculating a difference of a predetermined fuelcut speed value from an existing engine speed, and means for determining the overspeed condition when the calculated difference is greater than zero said control circuit including means for determining a first interval during which said fuel supply means operates in the fuelcut mode to terminate fuel delivery to said first cylinder group according to the calculated difference, said control circuit including means for determining a second interval during which said fuel supply means operates in the fuelcut mode to terminate fuel delivery to said second cylinder group according to the calculated difference, the second interval being shifted a predetermined value with respect to the first interval to avoid overlap of the first and second intervals.

Claim 6

An apparatus for controlling a multi-cylinder type internal combustion engine including first and second cylinder groups each including at least one cylinder, comprising: sensor means for generating electrical signals indicative of engine operating conditions including engine speed; a control circuit coupled to said sensor means for calculating an appropriate value respectively at uniform intervals, the calculation being made according to engine operating conditions; fuel supply means coupled to said control circuit for supplying fuel to said first and second cylinder groups in an amount corresponding to the calculated value; said control circuit including means responsive to an overspeed condition for operating said fuel supply means in a fuelcut mode to alternatively terminate fuel delivery to said first cylinder group and fuel delivery to said second cylinder group, means for calculating a difference of a predetermined fuelcut speed value from an existing engine speed, and means for determining the overspeed condition when the calculated difference is greater than zero said control circuit including means for determining a first interval during which said fuel supply means operates in the fuelcut mode to terminate fuel delivery to said first cylinder group according to the calculated difference, said control circuit including means for determining a second interval during which said fuel supply means operates in the fuelcut mode to terminate fuel delivery to said second cylinder group according to the calculated difference, the second interval being shifted a predetermined value with respect to the first interval to avoid overlap of the first and second intervals.