Abstract: A jet engine actuation system includes a first ring gearbox, a second ring gearbox and an actuator. The first ring gearbox includes a first ring driveshaft coupled to a first portion of a synchronization ring included in a jet engine. The second ring gear box includes a second ring drive shaft coupled to a second portion of the synchronization ring. The actuator has a first actuator gearbox configured to generate a first rotational output and a second actuator gearbox configured to generate a second rotational output. A first drive shaft transfers the first rotational output to the first ring gearbox and a second drive shaft transfers the second rotational output to the second ring gearbox. The actuator simultaneously controls the first and second actuator gearboxes such that the first and second rotational outputs are simultaneously transferred to the first and second ring gearboxes to rotate the synchronization ring.

Abstract: A valve includes a housing having an inlet and an outlet. A spool is fixed within the housing and defines a flow window therethrough for fluid communication between the inlet and the outlet. A piston is slidingly engaged in a piston compartment of the spool. A sleeve is slidingly engaged with the spool on an outer surface of the spool. The piston and sleeve are operatively connected for common motion along a sliding axis relative to the spool and housing between a first position in which the sleeve occludes the flow window to inhibit flow from the inlet to the outlet, and a second position in which the sleeve unoccludes the flow window to allow flow from the inlet to the outlet.

Abstract: An excitation circuit includes an operational amplifier, a transistor circuit, a switch, and a pull-down resistor. The operational amplifier receives an excitation input voltage at a non-inverting input and provides an operational amplifier output. The transistor circuit receives the operational amplifier output and provides a transistor circuit output. The transistor circuit output is connected to an inverting input of the operational amplifier. The switch is connected between the operational amplifier output and the transistor circuit. The switch is opened to disconnect the operational amplifier output from the transistor circuit. The pull-down resistor is connected between an output of the switch and ground, wherein the pull-down resistor turns off the transistor circuit when the analog switch is opened.

Abstract: A motor housing includes a central body having a central cavity region configured to receive an electric motor. Also included is a first end portion having a first inner surface that defines a first internal cavity region configured to receive a first end winding of a stator of the electric motor, wherein the first internal cavity region comprises a first radius defined by a distance from a main axis of the motor housing to the first inner surface. Further included is a second end portion having a second inner surface that defines a second internal cavity region configured to receive a second end winding of the stator, wherein a ratio of the first radius to a first end portion wall thickness ranges from 19.89 to 27.85.

Abstract: A power conversion system includes a power source, a matrix converter, and a controller. The power source is configured to produce an input power. The matrix converter is configured to convert the input power to output power and includes a plurality of normally-on switches and a plurality of normally-off switches. The controller is configured to control the plurality of normally-on switches and the plurality of normally-off switches to control the output power. The plurality of normally-on switches provide the input power directly as the output power when the controller is inactive.

Abstract: A pressure regulating valve includes a housing having a cavity therein with at least a first port, a second port and a third port in fluidic communication with the cavity, and a spool movable within the cavity. The spool separates the cavity into at least a first space and a second space, the first port and the second port are in alterable fluidic communication with the first space with movement of the spool altering a flow area connecting the first port with the second port. The third port connects to the second space through a variable flow area opening that is configured to alter a rate of movement of the spool.

Abstract: A fluid transfer coupling is described that includes first and second connectable coupling members that together contain a sealed interior space when connected. A gas or steam purge inlet and a purge outlet are disposed in fluid communication with the sealed interior space for purging potential contaminants out of the interior space. The coupling also includes a vacuum port in fluid communication with the sealed interior space for drawing a vacuum on the sealed interior space and optionally testing the space for an adequate seal. The first coupling member includes a first fluid transfer conduit and the second coupling member includes a second fluid transfer conduit. The first and second fluid transfer conduits are positioned such that they can be connected together within the sealed interior space when the first and second coupling members are connected.

Abstract: The present invention relates to a coupling formation of a pipetting channel of a pipetting device for coupling of an implement, for instance a pipette tip, or a laboratory instrument, laboratory tool or the like, thereto, wherein the coupling formation surrounds a pipetting channel section which extends along a pipetting channel axis which defines an axial direction, wherein the coupling formation additionally has, at its free longitudinal end, a pressure-imparting orifice into which the pipetting channel section opens and has, at its radially outer surface which surrounds the pipetting channel axis and extends principally in axial direction and in peripheral direction about the pipetting channel axis relative to the pipetting channel axis, a coupling projection which yields in the radial direction, which is characterized in that the coupling projection is provided so as to be essentially undeformable but radially movable on a spring arrangement which is elastic in radial direction.

Abstract: An outlet header of a heat exchanger is provided. The outlet header defines a flow-tap-off duct and includes an L-tube. The L-tube defines first and second legs. The first leg is fasteningly installed in the flow-tap-off duct such that the second leg is directed toward a cold-cold corner of the heat exchanger. The second leg is configured to capture cool air from the cold-cold corner for providing the cool air to and through the flow-tap-off duct and exterior the heat exchanger.

Abstract: A permanent magnet alternator (PMA) includes a rotatable shaft, windings, a shunt regulator circuit, and a speed detection circuit. The rotatable shaft is connected electromagnetically to the windings. The shunt regulator circuit is electrically connected to the windings. A current sense transformer with a primary coil is electrically connected to the shunt regulator circuit. A secondary coil is electrically connected to a comparator circuit with reference voltage and generates voltage pulse indicating PMA speed. The voltage pulses form an output corresponding to and indicative of rotation speed of the shaft suitable for processing by a processor to present a PMA speed indication for use in the overall system architecture as a measurement parameter.

Abstract: An aspect is a thrust plate assembly for an air cycle machine. The thrust plate assembly includes an annular body defined by an outer rim and a main bore. The annular body includes a nozzle side and a thrust bearing side. The nozzle side includes a nozzle region proximate the outer rim and a turbine rotor region proximate the main bore, where the outer rim has an outer diameter. The thrust plate assembly also includes a main bore seal installed in the main bore. The main bore seal has an inner diameter, where a ratio of the outer diameter of the outer rim to the inner diameter of the main bore seal is between 3.94 and 3.96.

Abstract: A current sense system includes a current transformer having a primary coil and a secondary coil, wherein the secondary coil has a first and second terminal; a burden resistor connected between the first terminal of the secondary coil and ground; a monitor circuit that measures current in the primary coil by monitoring voltage across the burden resistor; and a built-in test (BIT) circuit connected to the second terminal of the secondary coil. The BIT circuit provides a virtual ground during normal operation, and either a positive voltage or a negative voltage during test operations.

Abstract: A support bracket for a cabin air compressor (CAC) assembly includes a CAC mounting portion formed substantially orthogonal to an access portion and a structural support portion. A cross-support bracket mounting portion is formed at an angle relative to the access portion. An upper lug portion is formed at an angle relative to the access portion and substantially orthogonal to an upper lug. A plurality of CAC mounting holes is formed in the CAC mounting portion. The CAC mounting holes are distributed in an arc configuration along a CAC mounting hole circle radius. A plurality of lower slotted holes and an upper slotted hole are formed in the cross-support bracket mounting portion. A ratio of the CAC mounting hole circle radius to a length defined between the lower slotted holes and the upper slotted hole is between 5.93 and 6.25.

Abstract: A propeller blade includes a foam core formed of a combination of polyuria and polyvinyl chloride (pvc), an adhesive layer formed on the core and a structural layer that covers at least a portion of the adhesive layer and that surrounds at least a portion of the foam core.

Abstract: A stand for a musical keyboard is both stable in a deployed configuration and conveniently compact and portable in a collapsed configuration. The separation of the arms and legs may not change in width as the height of the stand is adjusted. The stand has two “floating” V's, one for the arms and one for the legs. These components slide vertically in slots in a central column and are locked in place with clamps that wrap around the column. To adjust the height of the stand, a user loosens either or both the top and/or bottom clamp (arm clamp or leg clamp) and slides the associated floating V up or down along the center column, then re-tightening the clamp when adjustments are finished. For transport and storage, the user loosens each clamp and rotates the arms or legs in, towards the column.

Abstract: A system for controlling an electromechanical device includes a motor drive, a main controller, a voltage regulator and a resistor-capacitor circuit. The motor drive controls an electric motor of the electromechanical device. The main controller provides motor commands to control the motor drive that are provided by providing command voltage on at least one command line. The voltage regulator circuit receives the command voltage and provides a motor voltage to power the motor drive. A capacitor of the resistor-capacitor circuit is charged by the command voltage, and the motor voltage is controlled based upon charge of the capacitor.

Abstract: A check valve for a housing with adjacent first and second apertures separated by a septum comprises a hinge pin, a first flapper, and a second flapper. The hinge pin is located downstream of the septum. The first flapper is anchored via the hinge pin, and is rotatable about the hinge pin to block the first aperture when in a closed position. The second flapper is anchored via the hinge pin, and comprises a primary flapper section and a counterbalance section. The primary flapper section is rotatable about the hinge pin to block the second aperture when in a closed position. The counterbalance section extends upstream from and substantially parallel to the primary flapper section, towards the first aperture.

Abstract: An apparatus for use in testing protective masks for leaks. The apparatus includes a test head assembly for supporting at least a portion of a protective mask to be tested for leaks. The test head assembly may be freestanding, mounted directly on a mask tester or integral with the mask tester. The test head assembly includes a body and a cover. The body includes a head section simulating at least a portion of a human head. The cover is mounted on the body to cover at least a portion of the head section. The test head assembly is preferably configured such that a portion of the cover can be inflated while the remaining portion of the cover remains in a relaxed state and in contact with the corresponding portion of the body.

Abstract: A remote power unit has an inlet duct and an outlet duct in a housing. The inlet and outlet ducts are configured to receive and expel cooling air from the remote power unit. A plurality of slots within the housing each hold a printed wiring board. A door is attached to each of the slots, and each door has a shape thermal memory element. The shape thermal memory element is used to open and close the doors to either allow or prevent cooling airflow from passing along the printed wiring board. In this way, cooling air use is reduced to only those areas where cooling is needed.

Abstract: An exemplary containment structure includes an annular wall configured to receive a rotatable portion of a turbomachine. A plurality of apertures extend radially through the annular wall. The apertures have a varying circumferential width.