Patent ID: 8398004

Claim:
A hydraulic system for operating a feed auger and spinner of a spreader, including: first and second fluid motors for driving the feed auger and spinner, the first and second fluid motors having respective fluid inlets and outlets; a first solenoid-operated pressure-compensated proportional control valve including a pressure compensating spool and having an inlet configured to receive pressurized fluid from a source thereof, a regulated flow outlet connected to the inlet of the first fluid motor, and a bypass flow outlet, whereby operation of the first valve controls the volume of flow of pressurized fluid supplied to the inlet of the first fluid motor via the regulated flow outlet with the balance of flow bypassing the first fluid motor; a second solenoid-operated pressure-compensated proportional control valve including a pressure compensating spool and having an inlet connected to the outlet of the first fluid motor and the bypass flow outlet of the first valve, a regulated flow outlet connected to the inlet of the second fluid motor, and a bypass flow outlet, whereby operation of the second valve controls the volume of flow of pressurized fluid supplied to the inlet of the second fluid motor via the regulated flow outlet of the second valve with the balance of flow bypassing the second fluid motor; and first and second pressure-relieving restricted flow passages respectively connected between the regulated flow outlets and bypass flow outlets of the first and second valves for preventing pressure buildup at the regulated flow outlets of the first and second valves, thereby to assure proper operation of the compensator spools of the first and second valves.