rotorque.
Doman had a similar idea.
Web page
Sketch of rotorhead
As mentioned by Mart, a few years ago while developing this
Hub - 3-blade - Constant Velocity Joint w/ Hub Spring the gentleman at Thompson and I discussed CVJ's.
If interested, the following is the fundamental difference between our two ideas.
The Thompson coupling converts the double universal joint into a Constant Velocity Joint by the use of linkages to maintain the correct position of the simple housing. The Thompson coupling may be an ideal solution for conventional CVJ applications, since it offers no resistance to angular change and can except axial loading. However, for a helicopter rotor, a spring resistance to changes in the axial angle between the driver shaft (mast) and the driven shaft (rotorhub) is desired, since it acts as a
hub spring, in addition to maintaining position.
Dave