The tilting shelf vertical conveyor has a frame with a front transfer area and a rear return area. Sprockets rotate on horizontal axes at the upper and lower ends, to drive an endless chain. Shelves are pivotally mounted for rotation about horizontal axes on the chain to define axially opposed shelves (10a). The chain and shelves move in a vertical conveying path between the sprockets in the front area and in a vertical return path at the rear. - A first pair of rollers (23,24) are mounted on one axial end of each shelf for rotation about parallel spaced horizontal axes. A second pair (32,33) of rollers are mounted on the other axial end of each shelf for rotation about parallel spaced axes. The rollers engage cam tracks to hold the shelves horizontal. (3/3) EPAB- EP--81574 B A tilting shelf, vertical conveyor, comprising a frame (1) having an upper end, a lower end, a front transfer area, and a rear return area opposed to the front area; two sprockets each (2,4 and 3,5 respectively) mounted for rotation about one horizontal axis each on the frame (1) at its upper and its lower end respectively; two endless chains (6,7) drivingly engaging and operatively mounted about the respective upper and lower pairs of sprockets (2,4,3,5) for rotation therewith in respective generally vertical parallel planes; a plurality of shelves (10) pivotally mounted for rotation about respective horizontal axes on the chains (6,7) to define axially opposed shelf ends and for travel with the chains (6,7); the chains (6,7) and shelves (10) together moving in a generally vertical conveying path between the sprockets (2,4,3,5) in the front area, and further moving in a generally vertical return path between the sprockets (2,4,3,5) in the rear area; a first pair of rollers (23,24) mounted on one axial end of each shelf (10) respectively for rotation about parallel spaced apart horizontal axes; and a second pair of rollers (32,33) mounted on the other axial end of each shelf (10) respectively for rotation about parallel spaced apart horizontal axes; characterised in that for each shelf, a line connecting the axes of the first pair of rollers (23, 24) is generally perpendicular to the line connecting the axes of the second pair of rollers (32,33); only a single first cam track (15) having opposite terminal ends, is mounted on the frame (1) adjacent one axial end of the shelves (10), this first track (15) generally following the path of the chains (6,7) for only approximately one-half of the chains' travel; only a single second cam track (31) having opposite terminal ends, is mounted on the frame (1) adjacent the other axial end of the shelves (10), this second track (31) generally following the path of the chains for only approximately one-half of the chains' travel; - EP--81574 B A tilting shelf, vertical conveyor, comprising a frame (1) having an upper end, a lower end, a front transfer area, and a rear return area opposed to the front area; two sprockets each (2,4 and 3,5 respectively) mounted for rotation about one horizontal axis each on the frame (1) at its upper and its lower end respectively; two endless chains (6,7) drivingly engaging and operatively mounted about the respective upper and lower pairs of sprockets (2,4,3,5) for rotation therewith in respective generally vertical parallel planes; a plurality of shelves (10) pivotally mounted for rotation about respective horizontal axes on the chains (6,7) to define axially opposed shelf ends and for travel with the chains (6,7); the chains (6,7) and shelves (10) together moving in a generally vertical conveying path between the sprockets (2,4,3,5) in the front area, and further moving in a generally vertical return path between the sprockets (2,4,3,5) in the rear area; a first pair of rollers (23,24) mounted on one axial end of each shelf (10) respectively for rotation about parallel spaced apart horizontal axes; and a second pair of rollers (32,33) mounted on the other axial end of each shelf (10) respectively for rotation about parallel spaced apart horizontal axes; characterised in that for each shelf, a line connecting the axes of the first pair of rollers (23, 24) is generally perpendicular to the line connecting the axes of the second pair of rollers (32,33); only a single first cam track (15) having opposite terminal ends, is mounted on the frame (1) adjacent one axial end of the shelves (10), this first track (15) generally following the path of the chains (6,7) for only approximately one-half of the chains' travel; only a single second cam track (31) having opposite terminal ends, is mounted on the frame (1) adjacent the other axial end of the shelves (10), this second track (31) generally following the path of the chains for only approximately one-half of the chains' travel; USAB- US4421227 A The tilting shelf type vertical conveyor has shelves pivotally mounted between two endless chains driven by pairs of upper and lower sprockets. It has a shelf control having a single track formed by a first track half adjacent one chain and a second track half adjacent the other chain. - One side of the shelf has two rollers for engaging in one of the tracks, whereas the other side of the shelf is provided with two rollers, at right angles to the first two rollers, for engagement with the other track. The shelf position is controlled during the conveying run by one set of rollers and track, and during the return run with the other set of rollers and track. (9pp)d