3. Ground equipment

3.1 Underground chain conveyor tractor

This is the typical machine for continuous handling in warehouses. The chain and all curves and motors are located below ground level. Carts are driven by a vertically movable spindle, enabling manual disengagement. In various variants, the underground circuit comprises a continuous track embedded in and flush with the ground. A 25 mm wide groove is left for the cart spindles. The chain, when fitted with bearing rollers, offers the best conditions of mechanical efficiency, at least as far as its own movement is concerned. A diagram of this conveyor is shown in figure 16 .

In order to reduce the height...