Abstract: A drive shaft assembly is formed from two concentrically arranged driveshafts fastened together near to one end of the driveshaft assembly so as to prevent relative rotation therebetween and connectable together near to an opposite end via a torque sensitive drivable connection. The torsional stiffness of the driveshaft assembly is primarily dependent upon whether one or both driveshafts are arranged to transmit torque. The drivable connection may be a mechanical lost motion connection which is operable to either connect the two driveshafts together or not based upon the magnitude of torque applied to the driveshaft assembly. Therefore, the driveshaft assembly provides more than one torsional stiffness allowing it to be better optimized to meet differing operational requirements.

Abstract: A drive shaft assembly is formed from two concentrically arranged driveshafts fastened together near to one end of the driveshaft assembly so as to prevent relative rotation therebetween and connectable together near to an opposite end via a torque sensitive drivable connection. The torsional stiffness of the driveshaft assembly is primarily dependent upon whether one or both driveshafts are arranged to transmit torque. The drivable connection may be a mechanical lost motion connection which is operable to either connect the two driveshafts together or not based upon the magnitude of torque applied to the driveshaft assembly. Therefore, the driveshaft assembly provides more than one torsional stiffness allowing it to be better optimized to meet differing operational requirements.