No. The tube is fixed and doesn't rotate. The wood blade with magnets all down it's "blade" stays in the bottom position under collection operation, with moop collecting all along the bottom only. To release what it's picked up, the blade inside is then rotated counter-clockwise (tube remains fixed in place), dragging the collected metal up and over the outside of the tube (also the source of the outside of the tube wearing). To avoid having a cam (and a movement beyond simply rotation), as the internal blade continues past the top of the ramp (which is fixed to the fixed tube), the moop cannot continue following the magnet as the ramp blocks it, and the magnet becomes too distant to hold the moop, and the moop falls down the ramp into the collection bin. The blade continues to the bottom position, and collection can begin again.
The alternate way has the internal blade fixed in reference to the tube (easier construction, less wear), and the resulting single assembly does not rotate during collecting. Both rotate for release (they're one structure) with the ramp in place but not fixed to the tube, hence the gap between ramp and tube means that not all of the moop will be released into the collection bin, and some moop may even jam between the ramp and tube.
In both, the tube is support up off of the ground by wheels, not shown in the diagram.
A series of blades could be constructed inside and collect and release as it moves along, but cost & weight go up, as does the force to push it along while rotating, and it requires an unattached ramp, with it's some retained moop and jam potential.
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