US Patent 8622697 Ram air turbine bearing spacer

A ram air turbine assembly includes a spacer that controls axial movement of a bearing assembly supporting rotation of a driven shaft to limit compression of a bearing biasing member. A gearbox includes mating gears that transfer power through a strut to a generator. Bearings support rotation of the driven shaft and the biasing member generates a biasing load to maintain desired alignment between the mating gears. Axial thrust reversals generated during operation are prevented from fully compressing the biasing member by a spacer that defines a minimum compressed height and that further limits axial movement of the bearing assembly responsive to the thrust reversals of the driven shaft.