MULTI-PRESSURE COMPENSATION OF VARIABLE DISPLACEMENT PUMP

摘要

A variable displacement pump is controlled throughout a broad range of operating conditions between a maximum pressure, low flow rate combination and a minimum pressure, high flow rate combination even when the pump is driven by a power limited prime mover. Different relief valves set at different operating pressures are automatically selectably connected to a control port of the pump in response to the actual flow rate of the fluid pumped by the pump reaching different flow rate set points.