US Patent 7901314 Transmission system for pump drive

A transmission system for use in a pump system comprising a prime mover driving a pump, the transmission system comprising: an epicylic gear system comprising a sun gear and a ring gear, and a planet gear engaged between the sun gear and ring gear; a main input drive arranged to be driven by the prime mover; an auxiliary input drive arranged to be driven by the prime mover; and an output drive arranged to drive the pump; wherein the main input drive is connected to the sun gear and either (i) the auxiliary input drive is connected to the ring gear and the output drive is lead from the planet gear; or (ii) the auxiliary input drive is connected to the planet gear and the output drive is lead from the ring gear.