Abstract: Multiple intensifier injectors with positive needle control and methods of injection that reduce injector energy consumption. The intensifiers are disposed about the axis of the injectors, leaving the center free for direct needle control down the center of the injector. Also disclosed is a boost system, increasing the needle closing velocity but without adding mass to the needle when finally closing. Direct needle control allows maintaining injection pressure on the fuel between injection events if the control system determines that enough fuel has been pressurized for the next injection, thus saving substantial energy when operating an engine at less than maximum power, by not venting and re-pressurizing on every injection event.

Abstract: Methods of operating low emission high performance compression ignition engines. After an expansion stroke during which combustion occurred, a predetermined amount of exhaust gas is trapped in the combustion chamber during the next compression stroke, typically by closure of an exhaust valve. Then fuel is injected into the combustion chamber, the amount of exhaust gas trapped being limited so that that compression stroke does not cause compression ignition. Then typically near the end of the following expansion stoke, air is injected so that compression ignition occurs at or near the end of the next compression stoke.

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: Hydraulic valve actuation systems and methods to provide variable lift for one or more engine air valves by way of a variable position hard stop. Various embodiments are disclosed, including embodiments controlling lift by providing a choice of two different fixed stops, three different fixed stops, stops continuously variable throughout a range of lifts, and a fixed stop and stops continuously variable throughout a range of lifts. The valves controlled by a variable position hard stop may be a single engine intake or exhaust valve, or multiple valves of any number, and of either intake or exhaust valves or both, or of one intake or one exhaust valve for one or more cylinders in engines having more than one intake or exhaust valve per cylinder. Dashpot deceleration of engine valve velocity on opening to the hard stop and on engine valve closure is disclosed, as are other aspects and embodiments of the invention.

Abstract: Hydraulic valve actuation systems and methods to provide variable lift for one or more engine air valves by way of a variable position hard stop. Various embodiments are disclosed, including embodiments controlling lift by providing a choice of two different fixed stops, three different fixed stops, stops continuously variable throughout a range of lifts, and a fixed stop and stops continuously variable throughout a range of lifts. The valves controlled by a variable position hard stop may be a single engine intake or exhaust valve, or multiple valves of any number, and of either intake or exhaust valves or both, or of one intake or one exhaust valve for one or more cylinders in engines having more than one intake or exhaust valve per cylinder. Dashpot deceleration of engine valve velocity on opening to the hard stop and on engine valve closure is disclosed, as are other aspects and embodiments of the invention.

Abstract: Hydraulic valve actuation systems and methods to provide multiple lifts for engine valves using fixed or hard stops at each lift. The fixed or hard stops provide a very repeatable selection of engine valve lifts dependent on engine operating conditions. For full valve lift, unidirectional hydraulic dashpots are used to decelerate the engine valve, both as it approaches the full lift fixed stop, and as the engine valve approaches the valve seat from the engine valve full lift position. Various embodiments and methods of operation are disclosed.

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: Two stage spool valves having, in a single assembly, a first stage spool and a second stage spool. The first stage spool may have a solenoid actuator with a return spring, with the second stage spool having either a hydraulic return or a spring return, or both. The solenoid actuator may be comprised of a stationary structure defining a magnetic flux path, including a stationary structure pole face, that together with a moveable structure, including a moveable structure pole face, define a substantially zero air gap magnetic circuit when the solenoid actuator is actuated, the pole faces of the stationary structure and the moveable structure each being defined in part by soft magnetic iron and in part by hardened steel, the hardened steel of the moveable structure contacting the hardened steel of the stationary structure and the soft magnetic iron of the moveable structure being face to face with the soft magnetic iron of the stationary structure when the solenoid actuator is actuated.

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.

Abstract: Herein disclosed is a combustion cell adapted for an internal combustion engine, comprising i) a hydraulic engine valve actuation portion capable of providing a selection of two different and stable engine valve lift (i.e., open) positions per engine valve or per coupled engine valves and ii) a fuel injection portion capable of providing a selection of comprising i) a hydraulic engine valve actuation portion capable of providing two stable engine valve lift positions and ii) a fuel injection portion capable of providing a selection of one, two or three injection pressure levels for injection fuel. The combustion cell provides more flexibility in control of incoming intake air, outgoing exhaust gas, and/or incoming injection fuel relative to an engine combustion chamber so as to better match engine operating conditions that may change over time.