Abstract: Digital regulators using a plurality of latching solenoid actuators, each having a spring return, the springs being configured to provide a force on the valve member of a regulator, when the solenoid actuators are unlatched, in a binary progression. The solenoid actuators are selectively latched by an latching current pulse and retained in the latched condition by residual magnetism in a zero air gap magnetic circuit. Various embodiments are disclosed, including embodiments having the solenoid actuators side by side and in a stacked relationship, solenoid actuators having springs providing a spring force in a binary progression, solenoid actuators having equal springs and distributed in a binary progression from a hinge axis, and solenoid actuators not distributed in a binary progression from a hinge axis and not distributed in a binary progression from the hinge axis. Embodiments are also disclosed having the capability of interpolating between binary settings of the digital regulator.

Abstract: A device for controlling a temperature of a fluid includes a plurality of valve assemblies, each coupled to a cold fluid supply, a hot fluid supply, and an outlet line. An orifice is coupled to each outlet line and to a combined outlet line that is common to all orifices. Each of the orifices has a proportionally different flow area. Hot and cold fluid supply temperature sensing elements are coupled to supplies. A controller is coupled to the hot and cold fluid supply temperature sensing elements and the plurality of valve assemblies. The controller selectively couples one of the cold fluid supply or the hot fluid supply to the outlet line for each of the plurality of valve assemblies responsive to the cold fluid supply temperature sensing element, the hot fluid supply temperature sensing element, and a desired temperature in the combined outlet line.

Abstract: High efficiency, high pressure fixed displacement pump systems and methods of control. A typical application is for engine driven high pressure pumps for powering loads such as fuel injectors and/or hydraulic engine valve actuators. The pump systems include a control valve controllably coupling the pump output back to the pump input to stop the pumping when the desired pressure of the output is reached. Reinitiating pumping an increment in crankshaft angle before a load event based in the increment in pressure needed to reach the desired pressure at the crankshaft angle of the load event provides a simple control algorithm assuring accurate repeatability in the pressure at the beginning of a load event. Pumping throughout the load event minimizes the decrease in pressure during the load event. Providing underlap in the control valve minimizes pressure peaks and maximizes efficiently when starting and stopping the pumping action. Various embodiments are disclosed.