Abstract: A conveying apparatus for moving a plurality of spaced and interconnected support trays along horizontal pathways of different levels and thru pathways interconnecting the horizontal pathways. The apparatus includes tie rods interconnecting the sides of one support tray with another defining an endless chain of the latter and by crank members operatively connected to the tie rods and a pair of crank rods which extend into operative engagement with crank members of adjacent support trays, the latter as they travel through the conveyor pathways are maintained in uniform positions.