US Patent 7191965 Material spreader and method for using same

A material spreader includes a belt/chain assembly. The belt is mounted within the chamber of the material spreader and the chain remains out of contact with the material during the operation of the device. A sliding barrier is mounted at the rear of the belt, and moves from a forward position adjacent the front of the spreader to a rear position adjacent the rear of the spreader. One form of the hydraulic system utilizes a sensor for built up pressure within independently driven augers. In response to this pressure build up the sliding barrier speed is reduced.