MATERIAL HANDLING EQUIPMENT AND PARTS AND ACCESSORIES THEREFOR-NAMELY, GRAVITY TYPE ROLLER CONVEYORS, LIVE ROLLER CONVEYORS OF THE BELT AND CHAIN DRIVEN TYPE, SLAT CONVEYORS, PUSHER BAR CONVEYORS, BELT CONVEYORS, WHEEL CONVEYORS, CHAIN CONVEYORS, CONVEYOR DRIVES AND DRIVE TAKE-UP APPARATUS, TRANSFER CARS, TURNTABLES, ROLLER SPIRALS FOR CONTROLLED LOWERING OF ARTICLES BY GRAVITY, SLIDES AND CHUTES, RECIPROCATING CONVEYORS, VERTICAL CHAIN CONVEYORS, CURVES, DISAPPEARING ROLL SECTIONS, STOPS, ESCAPEMENTS, DEFLECTORS, GATES, MECHANICAL SWITCHES FOR CONTROLLING THE MOVEMENT OF ARTICLES ALONG, BETWEEN, AND TO AND FROM CONVEYORS, TILTERS AND ROLL-OVERS FOR TURNING ARTICLES ON END AND FOR ROTATING ARTICLES ON A HORIZONTAL AXIS IN THE COURSE OF MOVEMENT ALONG A CONVEYOR OR PROCESSING LINE, CASTER TABLE AND BALL PEDESTALS FOR TRANSFER OF ARTICLES BETWEEN CONVEYORS AND FOR TURNING OF ARTICLES IN A HORIZONTAL PLANE WITHOUT LIFTING OF SAME, TROLLEY CONVEYORS, INCLUDING TOW CONVEYORS OF THE OVERHEAD AND SUB-FLOOR TYPE, OVERHEAD TROLLEY AND POWER AND FREE CONVEYORS, RECIPROCATORY, POWERED CONVEYOR APPARATUS FOR MOVING ARTICLES BETWEEN PICK-UP AND DELIVERY STATIONS IN AN AUTOMATED ARTICLE STORAGE AND RETRIEVAL SYSTEM AND PLATFORMS FOR SUPPORT OF THE ARTICLES BEING TRANSFERRED BY THE SAME, STORAGE RACKS OF THE GRAVITY ROLLER TYPE, AND TILT-TRAY SORTERS