Method for controlling transitions in a variable displacement engine
First Claim
1. 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 crank angle degrees dependent on the mode of operation and may occur over a range of degrees with a minimum of 120 degrees, wherein the engine operates with uneven firing intervals in the four-cylinder mode, the uneven firing intervals including four successive firing events of a cycle with two successive firing events having a 120 crank angle degrees firing interval, and another two successive firing events of the cycle having a 240 crank angle degrees firing interval.
1 Assignment
0 Petitions
Accused Products
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.
33 Citations
12 Claims
- 1. 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 crank angle degrees dependent on the mode of operation and may occur over a range of degrees with a minimum of 120 degrees, wherein the engine operates with uneven firing intervals in the four-cylinder mode, the uneven firing intervals including four successive firing events of a cycle with two successive firing events having a 120 crank angle degrees firing interval, and another two successive firing events of the cycle having a 240 crank angle degrees firing interval.
- 11. A method comprising transitioning an engine with only four cylinders between two-cylinder, three-cylinder, and four-cylinder modes of operation, wherein the engine operates with uneven firing intervals in the four-cylinder mode, 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, adjusting a plurality of active mounts coupled to the engine and a chassis to provide a different input function during each transition in modes of operation of the engine.
Specification