The AD's are specific in identifying Spline wear as the salient concern. It is logical to conclude from this (I did not find in the AD) that slop in the splines can result in, and therefore cause additional thrust loading on the bearing. Rather than attenuating low levels of thrust (from Shaft), there may be enhanced levels; along with this, perhaps more rapid cycling (therefore damage to spline faces) of Thrust orientation (both directions?). More slop, more energy when each opposite face arrests the other component.
If Oil loss is patent, and addressed (AD?), the possibilities were known. A finely machined set of effacing surfaces, once worn, will wear faster, then faster. Failure point accelerates as wear continues.
I think it is illogical to point at an oiler, identify its failures, but then leave unaddressed the target (and the reasons) for the lubrication. The AD id's an aftward drift of the IP Shaft, this can be bearing wear, or spline wear, or both. Other? The isometric shows that the IP Shaft is made up of two separate Shafts.
Oil Fire. Fine. And???
From the patent, I think one of the reasonings behind its elegance is the accomplishment of constant contact spline to spline, as the torque is transferred, rather than a clash, thus attenuating wear, extending its service life. IMO
bear
Last edited by bearfoil; 8th Dec 2010 at 12:34.