A basic solution for belt contol is to physically link it to the spreaders tyre. This is done via a gearbox mounted on the driven shaft. The purpose built gearbox has no internal gear changes, reducing any mechanisms internally. Two speed is achieved by using a seperate input shaft position for the cage wheel. The Gearbox is oil filled for reduced maintenance.
The two speed on the gearbox give a wide range of application rates. The application rate is adjusted via the rear door opening. The belt speed is proportionate to the forward speed.
To select gear ratio simply remove cage wheel and mount on the other shaft. Similar to a pto shaft coupling.
Overload protection is present via a shear bolt on the driven wheel.