Method for controlling vibrations during transitions in a variable displacement engine
AssigneeFord Global Technologies, LLC
InventorsJames Douglas Ervin, Brad Alan Boyer, Gregory Patrick McConville, Kim Hwe Ku
Life of this patent
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Abstract
Methods and systems are provided for controlling vibrations during transitions between engine operating modes in a four-cylinder engine. One method includes timing a transition in engine operation between two-cylinder, three-cylinder, and four-cylinder modes with a sequence of firing events such that successive firing events are separated by at least 120 crank angle degree intervals. Vibrations resulting from transitions may be countered by adjusting active mounts, the active mounts being adjusted in synchronization with a valvetrain switching solenoid.
Claims20
A method, comprising:
- transitioning an engine with only four cylinders between two-cylinder, three-cylinder, and four-cylinder modes of operation with a sequence of firing events, the sequence including at least two successive firing events separated by at least 120 crank angle degrees;
- and
- adjusting one or more active mounts coupled to the engine in response to the transitioning.
A method comprising:
- operating an engine with only four cylinders in a three-cylinder mode by deactivating a first cylinder and firing a second cylinder, a third cylinder, and a fourth cylinder 240 crank angle degrees apart;
- transitioning engine operation to a four-cylinder mode by activating the first cylinder;
- and
- firing the first cylinder between firing events in the fourth cylinder and the third cylinder.
A method, comprising:
- operating an engine with only four cylinders in a two-cylinder mode by firing a first cylinder and a second cylinder 360 crank angle degrees apart;
- transitioning engine operation to four-cylinder mode by activating a third cylinder and a fourth cylinder, firing the third cylinder 120 crank angle degrees after firing the first cylinder, and firing the fourth cylinder 240 crank angle degrees after firing the second cylinder;
- and
- actuating one or more active mounts in response to the transitioning.
Dependencies are inferred from the claim text.