Grundfos Challenge (version 2)

Grundfos Challenge: Design and integration of a gear unit for a hydronic valve into an enclosure box (version 2)

Realised requirements:

Gear ratio 500…1500 RPM (780)
Output torque 20 +/-1 Nm
Radial load to output shaft withstand 300 N
Assembly direction Z
Case walls thikness >/= 1 mm
Total efficiency 0.94
Resource 2000 (6700) hours
Not need lubricate
Not need service

Using a magnetic coupling to limit torque and adjusting (the maximum allowable decrease) the amount of lateral clearance in two stages to obtain a given hysteresis value on the output shaft.

The modified design of the mechanism to minimize lateral clearance in a three-stage gear transmission. Instead of eccentric bushings, a composite (for assembly) bracket in linear guides and springs is used. The direction of movement of the bracket in the middle between the first and third steps.
For guaranteed elimination of the lateral clearance simultaneously with two gears, the bracket with the axis of the second stage has 2 degrees of freedom (clearance along the main movement). This ensures that hysteresis is eliminated automatically without disassembling the gearbox.
Everything else is as in the 1 version.
See more description in attached files...