US Patent 7748652 Electric hopper-spreader

A material spreading drive system for a hopper spreader having a conveyor and a spreader separately driven by two electric motors that are powered directly from the electrical system of the vehicle. The conveyor drive system includes a speed reducing gearbox that can very efficiently transmit power received from the conveyor motor to the conveyor, thus reducing the demand on the electrical system. As a result, the electrical system is capable of also powering a second electric motor that drives the spreader. Due to the improved efficiency of the conveyor belt system, increased conveying and spreading speed are possible as well as independent control over the operating speeds of the conveyor and spreader.