Abstract: The centrifugal pump includes a separable, multipartite impeller assembly and preferably incorporates a shock-absorbent shaft support that is tolerant of impeller vibrations or minor imbalances in the impeller assembly. The multipartite impeller assembly comprises an impeller portion, a wet-end magnetic coupler, and a radial bearing. The impeller portion and the wet-end magnetic coupler are secured together by a snap-fit joint, which is reinforced by a radial bearing adjacent to the snap-fit joint. The shaft support has an encapsulation junction which secures braces to a peripheral base.

Abstract: The antenna system and method for dynamically controlling radiation patterns provides an assortment of radiation patterns to increase the performance of communication systems, such as trunking communication systems and cellular communication systems. One embodiment of the antenna system permits a user to manually select a desired radiation pattern from the assortment of radiation patterns. For example, the user may manually select a desired radiation pattern via a graphical user interface of a general purpose computer, or via a conventional telephone. Another embodiment of the antenna system and method tailors radiation patterns in response to factors such as the locations of mobile units, the channel assignments of mobile units, and the transmissions of particular mobile units.

Abstract: The axial bearing includes a first ring and a second ring. During operation of the axial bearing, the first ring rotates with respect to the second ring. Over time the foregoing rotation produces wear of the first ring; consequently, exposes layers of the first ring to the second ring. The different layers of the first ring produce variations in the coefficient of friction within the axial bearing. If the axial bearing is associated with a drive motor, then the variations in the coefficient of friction change the load on the drive motor. The change in load upon the drive motor may be monitored to indicate axial bearing wear or the need for axial bearing replacement.

Abstract: The multipartite impeller assembly includes an impeller portion, a magnetic coupler, a snap-fit connector, and a radial bearing. The impeller portion and the magnetic coupler have complementary polygonal shapes which can be interlocked. The impeller portion and the magnetic coupler are secured together by a snap-fit connector, which is reinforced by a radial bearing adjacent to the snap-fit connector. The radial bearing prevents radial movement of the snap-fit connector or snap-fit joint, which could otherwise tend to release the snap-fit joint.

Abstract: The electronic ballast for a gas-discharge lamp includes an inverter. The inverter uses the combination of a step-up transformer, a resonant circuit, and clamping diodes to provide an operational inverter output voltage that is independent of the start-up output voltage of the inverter. During the start-up mode, the step-up transformer is used to provide the start-up voltage for the lamp and the resonant circuit is inactive. Clamping diodes prevent or inhibit the resonant circuit from resonating with potential parasitic capacitances during the start-up mode. During the operational mode, an oscillator is tuned relative to the resonant frequency of a resonant circuit to control the brightness of the fluorescent lamp.

Abstract: An axial bearing includes a ring, pads and a base. Multiple, independent pads are orientated in a curved or circular configuration with respect to one another. The pads are retained by recesses in the base. If the pump is installed in a centrifugal pump, the base is preferably integrated into a front impeller shroud. Each pad conforms in shape and size to a corresponding recess's shape and size. Each pad has a side which faces a face of the ring. Axial clearances between the base and the pads may be controlled by varying the pad heights. Fractured pads can potentially be retained in the recesses. The user may remove individual pads during repair and inspection of the axial bearing.

Abstract: A method for storing and retrieving information on a magnetic storage medium, such as magnetic tape, organizes files into data blocks of variable encoded block sizes. The encoded block sizes indicate file boundaries of files, intrablock data organization and/or interblock data organization to facilitate data retrieval. For example, if encoded block sizes indicate file boundaries, then filemarks are not needed to separate files from each other. During an encoding process, data blocks are assigned corresponding data formats and block sizes are preferably quantized to equal distinctive integer multiples of an encoding constant. Decoding is accomplished by performing a modulo function on the quantized block size to identify corresponding data formats assigned to the data blocks. One practical application of the method of storage and retrieval is recovery of a corrupt or a missing file directory, which references files stored on the magnetic storage medium.

Abstract: The grooved shaft for a magnetic-drive centrifugal pump preferably has an axial groove with a semi-elliptical or U-shaped groove cross section. Adjoining the axial groove is a flat area which is tapered tangentially relative to a substantially cylindrical shaft area. The grooved shaft optimally has a front shaft radius and a rear shaft radius, wherein the front shaft radius is smaller than the rear shaft radius such that the front shaft radius may be oriented near an impeller intake to decrease hydraulic flow resistance. Meanwhile, the rear shaft radius provides increased axial and radial load capacity for the grooved shaft. In practice, the grooved shaft is incorporated into a magnetic-drive centrifugal pump and the groove is statically oriented in a position of minimal radial loading.

Abstract: The axial bearing includes a first ring and a second ring. During operation of the axial bearing, the first ring rotates with respect to the second ring. Over time the foregoing rotation produces wear of the first ring; consequently, exposes layers of the first ring to the second ring. The different layers of the first ring produce variations in the coefficient of friction within the axial bearing. If the axial bearing is associated with a drive motor, then the variations in the coefficient of friction change the load on the drive motor. The change in load upon the drive motor may be monitored to indicate axial bearing wear or the need for axial bearing replacement.

Abstract: The seal assembly comprises a housing, a shaft, seals, and a reservoir. The housing has a hollow section bounded by a cylindrical surface and a first curved protrusion. The housing has a first channel and a second channel extending from the hollow section. The shaft extends through the hollow section. Seals seal the hollow section with respect to the shaft to form a chamber. The combination of the first curved protrusion and the sleeve cooperatively form a hydraulic pump for conveying a lubricating fluid from the chamber via the first channel to reservoir. The lubricating fluid is circulated from the reservoir to the chamber via a second channel. The seal assembly has a fluid level gauge or an optoelectronic leak detector for detecting leaks in the seals of the seal assembly or leaks in a fluid pump (i.e. a magnetic-drive centrifugal pump) coupled to the seal assembly.

Abstract: The radio frequency ferrite system for modulating, phase shifting, or attenuating radio frequency energy has a resonator, a ferrite polarizer, and coupling devices. The coupling devices are used to couple radio frequency signals to and from an interior of the resonator. The ferrite polarizer generates magnetic fields corresponding to an applied voltage or current. To produce phase modulation the ferrite polarizer may be used to detune the cavity from resonance by changing the orientation of the radio frequency signal with respect to a protrusion in the resonator. The ferrite system may be used for phase modulation, switching radio frequency signals, and amplitude modulation by arranging the coupling devices in various orientations and by simultaneously changing the polarization of radio frequency signals with the ferrite polarizer.