PRINT OR FLOW-COMPENSATED TAX CONTROL SYSTEM WITH A CONSTANT TORQUE AND VISCOSITY DETERMINATION

摘要

A variable displacement fluid pump system is provided having a pressure and flow compensated control system with constant torque and viscosity sensing over-ride acting on the control system. The system includes a viscosity sensing means receiving fluid from the pump and acting on the control means to over-ride the control means to reduce the pump displacement when the viscosity of fluid in the pump exceeds a predetermined value, a pressure sensing means receiving fluid from the pump acting on the control means to over-ride the control means and reduce pump displacement when the pressure in the system exceeds a predetermined value, at least one pressure compensated work port valve receiving pressure fluid from said pump and a variable by-pass valve receiving fluid from the pump not required by the pressure compensated work port valves to variably by-pass excess fluid from said pressure compensated valve and acting on said control means to vary the displacement of said variable displacement pump to satisfy the fluid requirements of said pressure compensated valve above a minimum established flow rate.