Abstract: A coupling shaft couples driving and driven shafts which are subject to relative misalignment. The coupling shaft has crowned male polygonal profiles on both of its ends, and which ends mate directly with corresponding female polygonal profiles carried by the driving and driven shafts. The crowned male profiles permit the coupling arrangement to act in a hinge like manner to accommodate the misalignment. Non-metallic bushings and adapters may be interposed between the coupling shaft and the driving and driven shafts to eliminate metal to metal contact and to thereby eliminate fretting and metal wear which would otherwise occur.

Abstract: A compliantly mounted damper (16,18) for rotating equipment of the type including a rotor shaft (2) and a quill shaft (6) coupling the rotor shaft (2) to a driver shaft (8) is disclosed. The damper includes a plate (14) rigidly mounted to the quill shaft (6) and a plate (16) compliantly mounted to the rotor shaft (2) so that the rotor shaft plate (16) follows the angular displacement of the quill shaft plate (14) due to shaft misalignment which may occur, while torsional damping is achieved.