Modification made on a hoist trolley, installing a rack and pinion drive system.
This system allows the trolley movements to be very precise avoiding the possibility of wheels slipping.
The two bronze gears are driven by the trolley motor and the two steel gears are rolling on the rack.
The idle trolley wheels remain the same as before. The only change to be made is placing a spacer on the wheels rolling path in order to compensate the rack’s height.