Rotary wheel type rock picker

A stone picker assembly comprising in combination a wheel mounted supporting chassis, a pick up reel journalled for rotation in said chassis about an axis transversely thereof, a rake component supported in said chassis and inclining downwardly and forward for ground engagement by a leading edge thereof, and curved around said pick-up reel axis so that said reel conveys material upwardly along the rake component, said pick-up reel including a plurality of transversely extending spaced and parallel pick-up bars secured thereto parallel to said pick-up reel axis, said rake component including a plurality of spaced and parallel longitudinally extending bars, each of said pick-up bars carrying a plurality of teeth spaced therealong and arranged such that each tooth passes between a respective pair of adjacent longitudinally extending bars of said rake component as said reel rotates, each tooth comprising a flat plate member lying in a respective plane radial to said pick-up reel axis and defining a leading edge and a trailing edge which converge toward an end of the tooth of greater spaced from said pick-up reel axis, the teeth of each of said bars being arranged on the respective bar alternately forwardly and rearwardly of the bar relative to its direction of movement around the pick-up reel axis such that two adjacent teeth in side elevation define a generally wedge-shaped gap between a forward edge of one of the two and a trailing edge of the other of the two, a vertical cylindrical screening wheel journalled for rotation about a horizontal axis longitudinal of said chassis such that the wheel is situated behind said pick-up reel, means mounting said screening wheel for rotation and means to drive said screening wheel, said screen wheel having an open front face for receiving material from said reel and an open rear face for discharge therefrom of said stones, means to initially retain within said screen wheel said material from said reel deposited on the lower side of said wheel until said material is elevated to a predetermined level by rotation of said wheel, a stone receiving container in said chassis rearwardly of said screening wheel, and said means to move said container from a stone receiving position to a stone dumping position and vice versa, said screening wheel having a peripheral cylindrical surface formed from a plurality of parallel spaced slats extending from said open front face of the wheel to said open rear face thereof, the slats being arranged to lie at an angle to a line in the surface parallel to the axis of rotation thereof such that an end of each slat adjacent the front face rotates angularly advanced relative to an end thereof adjacent the rear face such that said slats constitute the sole means for throwing said stones from said wheel into said container.