What is the driving device used when operating the hydraulic variable speed stacker for loading and unloading goods?

When operating a hydraulic variable speed stacker, the inching pedal plays a crucial role in controlling the machine's movement during the loading and unloading of goods. This device allows the operator to move the stacker at a very slow and controlled speed, enabling precision when positioning the machine close to racks or pallets. The inching pedal typically operates the hydraulic powertrain, allowing for incremental movement which is particularly important in tight spaces or when aligning forks with loads.

The other options serve different functions. The steering wheel is primarily used for directing the stacker's path but is not involved in speed control. A gas pedal, which would control acceleration and deceleration in a conventional vehicle, is not applicable to the hydraulic stacker as it does not operate like a traditional automobile. The reverse lever is important for changing the direction of travel but does not facilitate the gradual speed control that is necessary when maneuvering into and out of tight spots. Hence, the inching pedal is specifically designed to provide the necessary control for safe and effective operation during loading and unloading tasks.