Green ring and blue gear rotate around a fixed axis.
The ring carries two yellow gear shafts with brown cones.
The arrows show which link is the driving at different times.
1. If the green ring is driving:
- When the ring rotates anticlockwise, gearing forces (axial components) push the yellow gear shafts towards the femal cones of the ring, the yellow gear shafts can not rotate and make the blue gear rotate.
- When the ring rotates clockwise, gearing forces push the yellow gear shafts away from the femal cones of the ring, the yellow gear shafts rotate idly and the blue gear is kept immobile by load applied on it.
2. If the blue gear is driving:
- When the blue gear rotates anticlockwise, gearing forces push the yellow gear shafts away from the femal cones of the ring, the yellow gear shafts rotate idly and the ring is kept immobile by load applied on it.
- When the blue gear rotates clockwise, gearing forces push the yellow gear shafts towards the femal cones of the ring, the yellow gear shafts can not rotate and make the ring rotate.
For an embodiment of this mechanism the three helical gears are replaced by a non self locking worm drive (one worm gear and two worms).