we do several lifetime and performance tests with our robolink D joints. Until July, main topics were material and geometry optimisations for the gear and bearing components. Nowadays, we do lifetime tests for different joint types at different loads and speeds. The attached film shows or test unit with currently 9 test places, it will be enlarged in the next weeks up to 12 oor 14 test places.
Some numbers and facts that we found out until now:
# general efficiency factor for our current material combination (iglidur J with aluminum HC) is betweeen 0,28 and 0,35 (over all sizes).
# output torque at tooth-break: 19 Nm (size -20) and 30 Nm (size -30), measured at room temperature for first movement. Today we measure this “breaking torque” at continuous operation. Main influences are the rotation speed, and together with this, the temperature in the gear. We see a huge loss of “breaking torque” in operation. For size -20 we find a safe number at high speed rotation of 2,5 Nm (>100.000 cycles) and 3,5 Nm at low speed rotation.
we see good potential for improvement in the material combination and geometry optimisation.