Multiple stage torsional coupling with centering bearing and coil spring snubbing

A method of providing variable stiffness in a torsional coupling, the method comprising:

• providing a multi-stage torsional coupling comprising:
• an inner member;
• a sprocket plate connected to the inner member;
• one or more plates;
• an outer member rigidly attached to the one or more plates;
• and
• a plurality of damping stages that are arranged for sequential engagement by movement of the sprocket plate relative to the one or more plates to provide a variable stiffness over a range of angular displacement for the multi-stage torsional coupling;
• wherein the plurality of damping stages comprises at least a first damping stage and a second damping stage;
• wherein the second damping stage comprises one or more first coil spring assemblies, each of which comprises one or more coil springs;
• wherein:
• the inner member is connected to a first torsional connection and the one or more plates is/are connected to a second torsional connection;
• or
• wherein the inner member is connected to the second torsional connection and the one or more plates is/are connected to the first torsional connection;
• and
• rotating the sprocket plate relative to the one or more plates to sequentially engage the plurality of damping stages to provide stiffness between the first and second torsional connections that increases in a non-linear, or stepped, manner as the angular displacement of the sprocket plate relative to the one or more plates increases.