Patent ID: 11964757
Assignee: TEXTRON INNOVATIONS INC.
Field: Transport (Mechanical engineering)
Classification: CPC B  F | IPC B  F

Claim 17:
18. A tiltrotor aircraft having rotary and non-rotary flight modes, in the rotary flight mode, the tiltrotor aircraft operating at least two proprotor assemblies each having a plurality of proprotor blades, in the non-rotary flight mode, the proprotor assemblies are rotationally locked and circumferentially clocked for blade folding, for each proprotor assembly, the aircraft comprising:
a proprotor drive shaft coupled to and rotatable with the proprotor assembly;
a nonrotating airframe structure disposed proximate the proprotor drive shaft; and
a lock assembly having first and second lock members, the first lock member coupled to and rotatable with the proprotor drive shaft, the second lock member coupled to the nonrotating airframe structure, the first lock member including a plurality of bearing assemblies, the second lock member including a cradle having a plurality of asymmetric slots, each asymmetric slot including a leading ramp having a curved upper profile with a progressively decreasing angle and a trailing stop having a surface that is substantially parallel with a central axis of the second lock member;
wherein, the lock assembly has a plurality of positions including a disengaged position in which rotation of the proprotor drive shaft is allowed and an engaged position in which each of the bearing assemblies is seated within one of the asymmetric slots to prevent rotation of the proprotor drive shaft;
wherein, the lock assembly is actuatable between the disengaged and engaged positions;
wherein, each of the bearing assemblies has a diameter and each of the asymmetric slots has a height; and
wherein, the height is greater than the diameter.