Abstract: Retainer rings for locking in an N-sided shaft to restrict axial movement of components sandwiched between them. The retainer rings have inner edges bounding a central bore. The inner edges are defined by a series of N arcs whose distance from the bore's center decreases gradually along the inner edge from a first end to a second end of each arc. The rings are slid on to the shaft with the corners of the shaft aligned with the first ends of the arcs. Then the rings are rotated on the shafts toward the second ends of the arcs until the corners of the shafts jam against the inner edges. A special spanner wrench can be used to tighten and loosen the rings on the shaft.

Abstract: Retainer rings for locking in an N-sided shaft to restrict axial movement of components sandwiched between them. The retainer rings have inner edges bounding a central bore. The inner edges are defined by a series of N arcs whose distance from the bore's center decreases gradually along the inner edge from a first end to a second end of each arc. The rings are slid on to the shaft with the corners of the shaft aligned with the first ends of the arcs. Then the rings are rotated on the shafts toward the second ends of the arcs until the corners of the shafts jam against the inner edges. A special spanner wrench can be used to tighten and loosen the rings on the shaft.