by two i beams 86 which serve as rails that ride on two rollers 88 for each i beam this is best seen in the schematic side view of fig4 where the moveable bulkhead is shown in solid lines in its most downward position and in dotted lines in its most upward position the i beams and rollers are not shown in plan view but are located just above the feeder plate 42 shown in dotted lines in fig3 as the dozer blade pushes material into the feeder area the material pushes against the moveable bulkheads which ride on the rails up the rollers to their upward position as material is fed from the feeder plate into the conveyor the moveable bulkheads 52 move by gravity from their upper dotted line position of fig4 down the rollers 88 to their lower position the clearance between the bottom of the moveable bulkhead 52 and the feeder plate 42 may be from 11 2 inches to actually rubbing the moveable bulkhead permits substantially the entire feeder plate to be cleared of material which is especially important as cutting down on the cleanup time involved at the end of a shift especially when.