B65G 19/10

Conveyors comprising an impeller or a series of impellers carried by an endless traction element and arranged to move articles or materials over a supporting surface or underlying material, e.g. endless scraper conveyors for moving bulk material in open troughs or channels the impellers being scrapers similar in size and shape to the cross-section of the trough or channel and attached to a pair of belts, ropes or chains