Bearing support which allows to keep a turbofan engine functioning after the appearance of an imbalance

摘要

The method involves maintaining at least one bearing (15,18) on a support (17,19) having at least two levels of stiffness (35,36) agreed at the level of the normal stiffness corresponding to the correct rotor mode at a speed above a given level where the engine is throttled back during flight, and a lower level of stiffness corresponding to a mode suitable for a level below this speed. Play is provided (E) at least equal to the radial displacement (D) of the rotor at the first speed, under the effect of a maximum pre-established imbalance with the bearing support at a lower level. The bearing support is moved from a normal level to a lower level after the appearance of an imbalance at least equal to the pre established level.