Abstract: A motor-fan unit includes an end plate assembly, a motor assembly supported by the end plate assembly, and a shaft rotated by the motor assembly and extending through the end plate assembly. The fan assembly further includes a discharge shell, a tapered stationary fan which has a concave underside, and a rotating fan secured to the rotatable shaft and disposed between the discharge shell and the stationary fan. The tapered stationary fan includes a fan side which is substantially parallel and aligned with the frusto-conical shape of the fan disc of the rotating fan. A tapered fan shell is supported by the discharge shell and held in place by the stationary fan. A fan shroud secures the stationary fan and the fan shell to the discharge shell to prevent damage to a rotating fan secured to the shaft and positioned between the fan shroud and the stationary fan.

Abstract: A motor-fan unit includes an end plate assembly, a motor assembly supported by the end plate assembly, and a shaft rotated by the motor assembly and extending through the end plate assembly. The fan assembly further includes a fan secured to the rotatable shaft which is supported by the end plate assembly. The fan includes a fan disc having a substantially frusto-conical shape, a fan ring having a substantially frusto-conical shape, and a plurality of vanes connecting the fan disc to the fan ring such that the frusto-conical shapes are substantially parallel to one another. A diffuser with a tapered fan side is also provided between the fan and the end plate assembly, wherein the tapered fan side is substantially parallel with the fan disc.

Abstract: A labyrinth seal for a bypass discharge-type motor-fan unit includes a motor unit from which extends a rotating shaft that passes through an aperture in an end plate to drive a fan unit. Disposed within the aperture is a labyrinth seal configured to prevent liquid entrained in a working airflow from entering the motor unit. The rotating shaft also includes a vacuum bore, such that the negative pressure generated by the operation of the fan unit draws any liquid out of an evacuation zone maintained between the motor unit and the end plate. As such, the components of the motor unit are protected from being exposed to the liquid, thereby extending the operating life motor-fan unit.

Abstract: The system contains a voltage reference input positioned to be compared to an initial generator output voltage of an engine generator control unit by a subtractor circuit. A resistive voltage divider has at least one input series resistor, a subtractor input, at least two secondary resistors, and a ground. The input series resistor is disposed between the voltage reference input and the subtractor input. The secondary resistors are disposed between the subtractor input and the ground. At least two transistor switches connected between the secondary resistors and the ground. The reduced generator output voltages are from the input series resistor and the secondary resistors.

Abstract: A mixed flow fan assembly includes an electric motor, an impeller having a hub enclosing the motor, and a plurality of fan blades spaced circumferentially around the hub. The fan assembly also includes an axis of rotation extending through the hub, an annular venturi radially surrounding the impeller, and a mounting plate with an opening to allow for axial airflow positioned on one open end of the venturi. The venturi has at least one elongated slot to allow for radial airflow from the fan assembly, the slot being oriented substantially perpendicular to the axis of rotation and having a generally rectangular shape. Rotation of the hub and the fan blades caused by the electric motor generates both axial and radial airflow through the fan assembly.

Abstract: A Modbus data protocol register formatting system and method are disclosed. The system and method provide for the Modbus communications protocol request and recall of data stored in a register in the data base native format, and the conversion of the data into a different requested format. The system and method similarly provide for the writing of data into a device register from a known variable format into the data base native format. The ability to convert the data by a format converter after recalling the data, or before storing the data, obviates the need to store or write data in different or multiple formats. The inventive method uses a modified register mapping that comprises defined mapping elements identifying the data address location, the requested data format, along with the data variable. The register mapping is fully variable to provide for a wide range of data formats and data address formats.

Abstract: A measurement system having a first and second seal to create a sealed interface with a fluid and further having a rupturable barrier configured to relieve pressure when the pressure imparted to the first seal is less than the pressure imparted to the second seal, is disclosed. More particularly, the pressure relief element, which may be a rupturable barrier, is configured and positioned so that the second seal pressure limit is less than the first seal pressure limit. The primary elements of the system include the system housing, a sensing element having a first seal, with the sensing element within the housing, a second seal in fluid communication with the first seal, and a barrier that is rupturable when the pressure on the first seal is less than the pressure on the second seal.

Abstract: An apparatus and method for measuring the level of a wide range of varied surfaces or materials housed within vessels, and for detecting contact with a solid surface within the vessel is disclosed. A high precision radio frequency admittance measuring system, using capacitance to measure levels of process materials, coupled with detection element to sense contact of the detection element with a solid surface, such as a floating roof. An active element and ground element in coaxial relationship provides means for measuring the level of process materials including water, oil, kerosene, jet fuel, gasoline. Along with detecting the level of a solid surface within the vessel such as a floating roof. One preferred application of the inventive apparatus is to provide vessel or tank overfill protection. The apparatus detection element is capable of sensing level and non-level solid surfaces.

Abstract: An ultrasonic ranging device for ultrasonic ranging in the near zone. The device may include a transducer for generating an ultrasonic signal and for detecting an echo signal. The device may also include a processor for calculating the distance to a target object based on a first time period defined by a first set of ultrasonic signals when the target object is located outside the near zone and a second time period defined by a second set of ultrasonic signals when the target object is located within the near zone. The processor may also adjust the amplitude of the generated ultrasonic signal until the first set of ultrasonic signals is detected at the transducer.

Abstract: An arc detector comprising a voltage generator for detecting a voltage and an integrator for integrating said voltage with respect to time and generating an output signal corresponding to said integration. The arc detector also includes a discharge controller for controlling said output signal of said integrator, an amplifier for amplifying said output signal from said integrator and outputting an amplified signal; and a comparator for comparing said amplified output signal to a reference voltage and generating a detection signal based on said comparison.

Abstract: Systems and methods are provided for shielding integrated circuits from electromagnetic or electrostatic fields by locating an active device layer between two conductors that are electrically coupled together. In certain embodiments, a sensor comprises a conductive substrate that provides structural support and shielding to circuit elements in a semiconductor device layer. The device layer is between the conductive substrate and a shield layer that are electrically coupled together to create a shield or “Faraday box.” In certain embodiments, the device layer is substantially isolated from the conductive substrate and the shield layer by insulative layers. In certain embodiments, an input voltage powers the device layer and is also coupled to the substrate and the shield layer. Thus, the conductive substrate and the shield layer absorb and/or repel electrostatic charges or ions in a medium surrounding the sensor.

Abstract: A three-phase AC/DC active power converter provides an H-bridge that is controlled by a DSP (digital signal processing) controller that places the H-bridge in a voltage-boost mode of operation when voltage of a DC-link capacitor maintained by the H-bridge is near than the voltage input from a three-phase power source. The voltage difference between the boosted DC-link voltage and the three-phase power source voltage provides a voltage potential thereby giving the control loops a possible gain value. The gain value provides loop stability to thereby prevent an inrush of electrical current into the power converter upon startup. The converter also allows harmonic distortion to be modified through wave shaping of the normally pure sinus conduction signal.

Abstract: A curvilinear brush retainer and brushes for an electric motor assembly provides an end plate upon which is disposed a pair of curvilinear brush retainers. The brush retainers are configured to retain and support a pair of curvilinear brushes as they are biased against the commutator of the electric motor along a curvilinear path. Brush liners are disposed within the curvilinear path maintained by the brush retainers, serving to reduce the stiction or frictional force imparted to the brushes as they move, thereby reducing the temperature of the brush and extending their operating life.

Abstract: A Modbus data protocol register formatting system and method are disclosed. The system and method provide for the Modbus communications protocol request and recall of data stored in a register in the data base native format, and the conversion of the data into a different requested format. The system and method similarly provide for the writing of data into a device register from a known variable format into the data base native format. The ability to convert the data by a format converter after recalling the data, or before storing the data, obviates the need to store or write data in different or multiple formats. The inventive method uses a modified register mapping that comprises defined mapping elements identifying the data address location, the requested data format, along with the data variable. The register mapping is fully variable to provide for a wide range of data formats and data address formats.

Abstract: Embodiments of systems include primary and secondary seals, and pressure-relief devices that are configured and positioned so that the secondary seals can have maximum rated capacities substantially less than those of the primary seals.

Abstract: An arc detector comprising a voltage generator for detecting a voltage and an integrator for integrating said voltage with respect to time and generating an output signal corresponding to said integration. The arc detector also includes a discharge controller for controlling said output signal of said integrator, an amplifier for amplifying said output signal from said integrator and outputting an amplified signal; and a comparator for comparing said amplified output signal to a reference voltage and generating a detection signal based on said comparison.

Abstract: An air data sensor that determines a body's angle of attack, static air pressure, total air pressure, mach number, static air temperature and true air speed in one device using pressure and temperature readings. The air data sensor includes a probe that protrudes into an airflow to collect data, a base plate for attaching the probe to a body, and an electronics housing including electronics for interpreting the data collected from the probe.

Abstract: The present invention generally provides a motor-fan unit including a motor assembly having a shaft, a commutator supported on the shaft, and a pair of brushes in electrical contact with the commutator, a fan assembly having an impeller coupled to the shaft, an end plate assembly located between the impeller and the motor assembly said end plate assembly including a plate portion defining an opening throughwhich the shaft passes, wherein said commutator is located near the opening, and a pair of brush retainers adapted to receive the brushes formed on the plate portion adjacent said commutator, the brush retainers opening toward the fan assembly.

Abstract: An ultrasonic ranging device for ultrasonic ranging in the near zone. The device may include a transducer for generating an ultrasonic signal and for detecting an echo signal. The device may also include a processor for calculating the distance to a target object based on a first time period defined by a first set of ultrasonic signals when the target object is located outside the near zone and a second time period defined by a second set of ultrasonic signals when the target object is located within the near zone. The processor may also adjust the amplitude of the generated ultrasonic signal until the first set of ultrasonic signals is detected at the transducer.

Abstract: An arc detector comprising a voltage generator for detecting a voltage and an integrator for integrating said voltage with respect to time and generating an output signal corresponding to said integration. The arc detector also includes a discharge controller for controlling said output signal of said integrator, an amplifier for amplifying said output signal from said integrator and outputting an amplified signal; and a comparator for comparing said amplified output signal to a reference voltage and generating a detection signal based on said comparison.