Method for controlling transitions in a variable displacement engine
AssigneeFord Global Technologies, LLC
InventorsGregory Patrick McConville, Brad Alan Boyer, James Douglas Ervin, Kim Hwe Ku
Life of this patent
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Abstract
Methods and systems are provided for controlling transitions between engine operating modes in a four-cylinder engine. One method includes transitioning engine operation between two-cylinder, three-cylinder, and four-cylinder modes wherein the transitioning includes a sequence of firing events such that successive firing events are separated by at least 120 crank angle degree intervals.
Claims20
A method comprising transitioning an engine with only four cylinders between two-cylinder, three-cylinder, and four-cylinder modes of operation, the transitioning including a sequence of at least two firing events, wherein the at least two firing events are successive and are separated by at least 120 crank angle degrees.
A method comprising:
- operating an engine in a two-cylinder mode by firing a first cylinder and a second cylinder 360 crank angle degrees apart;
- transitioning engine operation to a three-cylinder mode by deactivating the first cylinder, and activating a fourth cylinder and a third cylinder;
- and
- firing the fourth cylinder 240 crank angle degrees after a firing event in the second cylinder.
A system, comprising:
- a vehicle;
- an engine including four cylinders arranged inline wherein a first cylinder, a third cylinder, and a fourth cylinder are deactivatable, the engine mounted on a chassis of the vehicle supported by at least one active mount, the at least one active mount being synchronized with a valvetrain switching solenoid;
- and
- a controller configured with computer readable instructions stored on non-transitory memory for:
- during a first condition,
- transitioning from two-cylinder mode of operation to three cylinder mode of operation by activating the third cylinder and the fourth cylinder, deactivating the first cylinder, firing the fourth cylinder 240 crank angle degrees after a firing event in a second non-deactivatable cylinder, and firing the third cylinder 240 crank angle degrees after firing the fourth cylinder;
- during a second condition,
- transitioning from two-cylinder mode of operation to full-cylinder mode of operation by activating the third cylinder and the fourth cylinder at different times, firing the third cylinder 120 crank angle degrees after firing the first cylinder, firing the second cylinder 240 crank angle degrees after firing the third cylinder, firing the fourth cylinder 240 crank angle degrees after firing the second cylinder, and firing the first cylinder 120 crank angle degrees after the fourth cylinder;
- and
- during a third condition,
- transitioning from three-cylinder mode of operation to four-cylinder mode of operation by activating the first cylinder and firing the first cylinder midway between firing events in the fourth cylinder and the third cylinder.
Dependencies are inferred from the claim text.