Twin spool rotor assembly for a small gas turbine engine

摘要

A small twin spool gas turbine engine with a hollow inner rotor shaft having solid shaft ends and an outer rotor shaft having a cylindrical portion on the compressor end that forms a forward bearing support surface and a turbine rotor disk on the turbine end that forms a aft bearing support surface. The inner rotor shaft includes solid shaft ends that project out from the cylindrical portion of the outer shaft on one end and out from the turbine rotor disk on the other end. An inner bearing housing is secured on the solid shaft ends of the inner rotor shaft. A threaded nut on the inner rotor shafts ends provide a compressive load to the inner bearing housings which results in a tension preload to the inner rotor shaft solid ends so that the bearing assemblies for the forward and aft ends of the twin spools do not become lose from the engine operation.