Patent ID: 7070381

Claim:
A refuse vehicle including a lifting arm mounted to the vehicle, said arm having a container holding and lifting apparatus, a positive displacement pump with an associated valve system including a first valve in fluid communication with a first drive mechanism that operates the lifting arm and a second valve in fluid communication with a second drive mechanism that operates the container holding and lifting mechanism, said valve system including a first spool mechanism for the first valve having a pressure compensator to maintain a constant flow rate of fluid through the first valve regardless of differential in pressure across the first valve for any given position of the first spool mechanism and a second spool mechanism for the second valve having a pressure compensator to maintain a constant flow rate of fluid through the second valve regardless of differential in pressure across the second valve for any given position of the second spool mechanism, and an electrical/electronic control system that controls the speed and direction of movement of the first and second spool mechanisms to vary the speed and govern the movement of the drive mechanism to which the each said spool mechanism is in communication.