Abstract: A flexible coupling includes a first hub, a flexible insert having a plurality of exterior lobes and a plurality of interior lobes, a retainer having an interior which engages the exterior lobes of the flexible insert, and a second hub having an exterior surface contoured to engage the interior lobes of the flexible insert. Protruding teeth are formed on wings of the second hub and positioned to engage sidewalls of openings formed in an inner lip of the retainer in the event that the flexible insert tears or shears, thereby preventing the second hub from going into a potentially damaging free spin mode.

Abstract: A flexible coupling including a first hub having an inner face, a flexible insert having a plurality of exterior lobes and a plurality of interior lobes, a retainer ring having an interior which engages the exterior lobes of the flexible insert, and a second hub having an exterior surface contoured to engage the interior lobes of the flexible insert.