US Patent 10520039 Isolating decoupler

An isolating decoupler comprising a hub, a pulley journalled to the hub, a torsion spring having a first torsion spring end welded directly to the hub, a wrap spring having a first wrap spring end welded directly to a second torsion spring end, a wrap spring outer surface fictionally engaged with a pulley inner surface, and a wrap spring second end temporarily engagable with the torsion spring first end whereby the frictional engagement between the wrap spring outer surface and the pulley inner surface is progressively released as a torque load increases.