Abstract: An electro hydraulic actuator with built-in fail safes is provided. Multiple accumulators are integrated into the actuator to improve reliability and redundancy. One or more accumulators can fail and the remaining accumulators provide sufficient energy to move the actuator to its fail-safe condition.

Abstract: A fuel system for use in an internal combustion engine, the fuel system comprising a source of high pressure fuel for supplying fuel through a single fuel supply path to an injector for injecting fuel, a first valve arrangement for controlling initiation of fuel injection and a second valve arrangement arranged in the fuel supply path, comprising a valve member which is operable between first and second positions to vary the rate of flow of fuel through the second valve arrangement, thereby to permit the fuel injection characteristics to be varied, in use.

Abstract: A system for automatically transferring the fuel from one or more engine fuel manifolds directly to the engine fuel tank(s) during engine shutdown using an ejector pump has been presented. A checkvalve, which may be integrated with the ejector pump, is also used. A metering valve initiates fuel flow shutoff and is used in the draining of the fuel manifolds, thereby eliminating the need for an additional solenoid dedicated mainly to the shutoff function. The shutoff and pressurizing valve provides flow division between manifolds and manifold drain for systems having multiple manifolds. The bypass valve is used to turn the motive flow and/or manifold drain functions on and off as a function of engine speed at start and shutdown.

Abstract: Fabrication processes for manufacturing and connecting a semiconductor switching device are disclosed, including an embodiment for dicing a wafer into individual circuit die by sawing the interface between adjacent die with a saw blade that has an angled configuration across its width, preferably in a generally V-shape so that the adjacent die are severed from one another while simultaneously providing a beveled surface on the sides of each separated die. Another embodiment relates to the manner in which damage to a beveled side surface of the individual die can be smoothed by a chemical etching process.

Abstract: A system for automatically transferring the fuel from one or more engine fuel manifolds directly to the engine fuel tank(s) during engine shutdown using an ejector pump has been presented. A checkvalve, which may be integrated with the ejector pump, is also used. A metering valve initiates fuel flow shutoff and is used in the draining of the fuel manifolds, thereby eliminating the need for an additional solenoid dedicated mainly to the shutoff function. The shutoff and pressurizing valve provides flow division between manifolds and manifold drain for systems having multiple manifolds. The bypass valve is used to turn the motive flow and/or manifold drain functions on and off as a function of engine speed at start and shutdown.

Abstract: A dynamic sealing arrangement for preventing leakage of a fluid along a shaft includes multiple seals and pressurized barrier sealant. According to one aspect, at least three seals are arranged along the shaft with pressurized barrier sealant between the first and second seals and a collection area is provided between the second and third seals to collect any leakage that might occur. Collected leakage, if any, is ported to an output port. According to another aspect, a unitary seal block member is provided that supports the dynamic sealing arrangement for the shaft and defines a piston chamber and a drilled passageway connecting the piston chamber and barrier sealant pressurization chamber between two seals. A substantial amount of plumbing is self contained in a single body minimizing the need for additional components or complexity.

Abstract: A pulsing valve assembly pulses metered fuel flow to a turbine engine. The pulsing valve assembly comprises a valve housing having an inlet and an outlet. A divider valve divides metered fuel flow into a first flow portion and a second flow portion. A first actuator sets a magnitude of a flow divide between the first and second flow portions. The valve assembly also includes a pulsing valve for pulsing the first flow portion and a second actuator for setting a frequency of pulsing valve. The pulsed and unpulsed flow portions are then joined and delivered to the turbine engine combustion chamber.

Abstract: An improved retainer, apparatus and method for retaining a circuit card are provided, through the use of a circuit card retainer comprising a length of spring wire defining a longitudinal axis of the retainer, lying in a plane of the retainer, and formed to define a wavy section of the retainer having peaks and valleys of the spring wire lying in the plane of the retainer with at least some of the peaks and/or the valleys being offset from the axis of the retainer. Some embodiments include a retainer guide, having a groove therein for properly orienting the wavy section of the retainer with respect to the circuit card.

Abstract: A fuel system for a gas turbine engine that utilizes a centrifugal pump is presented. The system includes a fuel metering valve that is adapted to set a metered flow of fuel, and a throttle valve that is adapted to accurately control pressure drop across the fuel metering valve. The throttle valve has at least two variable orifices and a compensation chamber between the variable orifices. The throttle valve includes a differential valve piston slidable in a valve body. The differential valve piston comprises working surfaces of at least two different diameters such that changes in chamber pressures effect different axial forces upon the piston.

Abstract: An apparatus and method to sense the onset of combustion stability is presented. An electrode is positioned in a turbine combustion chamber such that the electrode is exposed to gases in the combustion chamber. A control module applies a voltage potential to the electrode and detects a combustion ionization signal and determines if there is an oscillation in the combustion ionization signal indicative of the occurrence of combustion stability or the onset of combustion instability. A second electrode held in a coplanar but spaced apart manner by an insulating member from the electrode provides a combustion ionization signal to the control module when the first electrode fails. The control module broadcasts a notice if the parameters indicate the combustion process is at the onset of combustion instability or broadcasts an alarm signal if the parameters indicate the combustion process is unstable.

Abstract: The invention provides an ion sensor for use in a fuel nozzle of a gas turbine combustor and other combustor surfaces that uses thin-film coatings to form both the dielectric and electrode layer of the ion sensor and methods to provide an electrical connection to the electrode layer. The dielectric layer electrically insulates the sensor from the combustor surface, which is typically grounded. The electrode layer, typically a metallic material capable of withstanding high temperatures in the combustion environment without delamination from the dielectric layer, is applied over the dielectric layer and forms the ion-sensing electrode. A wire protrudes through the dielectric layer to connect to the electrode layer and provides for the ion-sensing electrode to be controlled outside of the combustion zone (e.g., to a control module for signal processing).

Abstract: A pressurized sealing arrangement suited for providing a seal between a valve stem and a valve body is provided. The sealing arrangement includes a piston that is restrained in and statically sealed to the valve body and which surrounds the valve stem. Contained within the piston is an annular seal packing that includes two sealing elements spaced apart by a spacer element. The piston includes a face acted upon by a process fluid flowing through the valve body in such a manner that the piston exerts pressure upon a lubricant cavity. The lubricant cavity is in fluid communication with the seal packing such that lubricant contained therein forms a lubricant ring around the stem. Lubricant is also thereby supplied to sealing elements of the packing seal. To prevent contamination of the seal packing, a removable cover is provided that encloses the piston and seal packing.

Abstract: A valve assembly is disclosed that provides for complete or partial fluid pressure balancing across the valve, and can be used for reducing valve actuation forces in order to employ electric actuation. The valve assembly includes a valve housing having a valve chamber, a flow passageway, and a piston chamber. A valve member is disposed in the valve housing and is movable along a valve axis. The valve member is subjected to a first pressure, which urges the valve in a first direction. To counteract this force, a piston integral with the valve member is slidably arranged in the piston chamber. One side of the piston is subjected to this first pressure to provide a counterbalancing force. A pressure passage fluid communication of the first pressure between the flow passageway and said one side of the piston.

Abstract: A high recovery sonic gas valve design with the inlet flow entering transverse and orthogonal to the outlet flow is presented. The configuration cancels the effects of the inlet flow entering orthogonal to the axis of the nozzle and diffuser. The inlet passage is curved in a manner to let the flow enter along the centerline of the nozzle and diffuser. The nozzle is contoured and provides upstream flow impedance. The diffuser is contoured with the area gradient varying from a low positive value at the nozzle throat then to a maximum value and finally dropping off significantly to near zero prior to the nozzle exit. The diffuser is nearly cylindrical and may extend past the valve outlet flange and protrude into adjacent piping.

Abstract: A method to automatically identify the inertia of an actuator (and the like) and load for tuning an observer-based controller is presented. The tuning is a one-time process that is initiated by a user when the actuator is installed. The control includes a model of the actuator with state feedback to set the desired dynamics.

Abstract: An apparatus for permitting both base and flush mounting a device to a surface is disclosed. The apparatus comprises a case housing a device and a frame. The frame is configured to attach to the case in both a base mounting and flush mounting configuration.

Abstract: A fluid metering valve includes a gear rack which is slidable on a valve stem in which a spring counteracts the force of an actuator to maintain a constant load on the gear mechanism to prevent backlash. Corresponding stop mechanisms between the gear and the shaft of a rotary actuator come into engagement with each other near a fully closed position of the fluid metering valve for zero calibration purposes upon power loss to the actuator. A single valve member and a single actuator of the fluid metering valve provides for both a shut-off function and a metering function.

Abstract: A system for automatically transferring the fuel from one or more engine fuel manifolds directly to the engine fuel tank(s) during engine shutdown using an ejector pump has been presented. A checkvalve, which may be integrated with the ejector pump, is also used. A metering valve initiates fuel flow shutoff and is used in the draining of the fuel manifolds, thereby eliminating the need for an additional solenoid dedicated mainly to the shutoff function. The shutoff and pressurizing valve provides flow division between manifolds and manifold drain for systems having multiple manifolds. The bypass valve is used to turn the motive flow and/or manifold drain functions on and off as a function of engine speed at start and shutdown.

Abstract: The present invention provides a system that controls the amount and timing of pilot fuel injection to obtain minimum NOx and UHC emissions. The system senses if combustion occurs, when combustion occurs, and/or the quality of combustion in the combustion chamber of each cylinder of the gaseous fuel engine and adjusts the amount and/or timing of the pilot fuel injected. The minimum amount of pilot fuel needed to ignite gaseous fuel in a combustion chamber is determined and injected into the prechamber or the combustion chamber of the engine. The actual start of combustion location is determined and the injection timing is adjusted if the start of combustion location is not approximately equal to a desired location. The amount of pilot fuel or injection timing is adjusted if a knock or a misfire has occurred or if the combustion quality measure is not approximately equal to a desired quality measure.

Abstract: A valve assembly is disclosed that provides for complete or partial fluid pressure balancing across the valve, and can be used for reducing valve actuation forces in order to employ electric actuation. The valve assembly includes a valve housing having a valve chamber, a flow passageway, and a piston chamber. A valve member is disposed in the valve housing and is movable along a valve axis. The valve member is subjected to a first pressure, which urges the valve in a first direction. To counteract this force, a piston integral with the valve member is slidably arranged in the piston chamber. One side of the piston is subjected to this first pressure to provide a counterbalancing force. A pressure passage fluid communication of the first pressure between the flow passageway and said one side of the piston.