US Patent 7347783 Driveshaft and method of manufacturing such a driveshaft

In a drive shaft including an outer tube extending from one end and a core shaft extending from the other end at least partially into the outer tube and an elastomer damping element disposed between the outer tube and the core shaft and being vulcanized to the outer tube and the core shaft for the transmission of a torque therebetween, several support rings are disposed in axially spaced relationship between the outer tube and the core shaft and abut the outer tube and the core shaft so as to permit relative movement between the outer tube and the core shaft but prevent bending of the drive shaft.