This isn't the right one for the application but is it what you are talking about?
That's exactly what I mean. By having two crosses in the joint instead of one, the angular velocity of the upper and lower shafts never changes. A single Cardan joint has unequal velocities at certain points in its rotation, and it's subject to binding at extreme angles of operation. That's why front drive axles need CV joints. Ever tried to make a tight turn on hard pavement with a 4X4 truck with the front axle engaged?
Jerry
