Abstract: A motor with positive torque parking positions. The motor includes a rotor which is rotatable about an axis of rotation and a stator in magnetic coupling relation with the rotor. The stator includes a plurality of teeth each having a radially extending shaft and an axially extending face. The faces of the stator teeth define an aperture for receiving the rotor and the faces of the stator teeth and the rotor define an air gap therebetween. Each stator tooth has a notch in its face that is approximately at least as wide as the shaft of the stator tooth so that the stator has a magnetic configuration relative to the rotor for parking the rotor in a rest position corresponding to a positive torque starting position. The motor also includes a winding on the shafts of the stator teeth and a control circuit for controlling current in the winding whereby an electromagnetic field is produced for rotating the rotor at a desired speed or torque during operation of the motor.

Abstract: A vibration isolating mounting system for an electric motor comprising includes a plurality of mounting arms formed from rod stock and each having one segment extending generally parallel to an axis of the motor and another segment extending generally perpendicular to the motor axis. The one is swaged at an end to create a pair of spaced protrusions. A plurality of circumferentially spaced retainers are mounted on the motor and adapted for passage of the end of the one segment when the arm is rotationally positioned to align the spaced protrusions in a first orientation. After insertion of the one end, the arm is rotated to align the protrusions away from the first orientation such that the protrusions engage the retainer and prevent axial motion of the one segment. In another form, a second retainer is spaced from the first retainer and the one end of each arm passes through both retainers to provide additional support between the arm and motor.

Abstract: Disclosed are methods of making dynamoelectric machines which include use of two sheet metal cup-shaped members to form a housing that completely surrounds and encloses the stator. The stator is assembled with a can in such a manner that the core of the stator is completely contained within the can. Thereafter, a cap is positioned at the exposed face of the stator and the cap and can are joined together by a sheet metal fastening technique which displaces material from one superposed sheet into a second sheet of material. The can and cap are precision formed so that they will have precision sized and located bearing receivers and core retention regions. Both the cap and the can are provided with multiple flange locations which are utilized for fastening the can and cap together during the assembly process.

Abstract: An electric motor includes a stator having a stator core, a start winding and first and second main windings. The first main winding and the start winding are configured to form a lower number of poles than the second main winding. The stator core forms a stator bore. The motor also includes a rotor having a rotor shaft concentrically arranged axially of the stator core and a rotor core positioned concentrically with the rotor shaft. Secondary conductors are arranged axially of the rotor shaft and extend through the rotor core. A plurality of permanent magnets are located at an outer periphery of the rotor core and are magnetized to form a number of poles equal to the number of poles formed by the second main winding.

Abstract: An active power line conditioner circuit having a series compensation system arrangement utilizes a transformer-coupled three-phase voltage-source inverter. A conventional metal oxide varistor (MOV) and bypass breaker combination are provided on the line side of the coupling transformer. A solid-state thyristor shorting ("crowbar") switch is provided on the secondary side of the coupling transformer across the outputs of the three-phase voltage-source inverter (VSI). The crowbar switch circuitry utilizes a diode bridge with a thyristor on the dc side of the bridge resulting in the simplification that only one active device need be gated. Crowbar switching logic activates the crowbar switch based on the exceeding of a threshold voltage measured at the dc power source link to the voltage-source inverter. A direct measure of dc source link voltage is employed to determine when to trigger the conduction of the crowbar thyristor switch.

Abstract: Apparatus and methods for inspecting electrical connections so as to determine the presence of fault connections between magnet wires and power leads are described. The apparatus includes a processing unit, a power supply unit, and a temperature sensing unit. The processing unit includes a programmable logic controller (PLC) having a central processing unit (CPU) and a plurality of input and output slots. The power supply unit includes a power lead connector configured to couple to the motor power leads and a power relay coupled to the PLC. The temperature sensing unit includes infrared thermometers to determine the temperature at the electrical connections between the stator magnet wires forming the motor windings and the power leads. The outputs of the thermometers are coupled to the programmable logic controller (PLC).

Abstract: An apparatus for use with a refrigeration system including a compressor for compressing a working fluid evaporated in an evaporator and condensed in a condenser. A control circuit initiates operation of a refrigeration cycle and initiates a defrost cycle in response to a defrost enable signal. The apparatus drives an air moving assembly moving air over the evaporator. A motor including a rotatable assembly is in driving relation to the air moving assembly. An energizing circuit selectively energizes the motor in response to the control circuit. A sensing circuit generates a speed/torque signal representative of a speed or a torque of the motor. A defrost initiating circuit generates the defrost enable signal when the speed/torque signal indicates that the speed is greater than a predetermined speed or the torque is greater than a predetermined torque.

Abstract: A fluoroscopic imager for observing a living creature with reduced x-ray dosage uses a video monitor for displaying frames of image samples received during respective ones of frame scan intervals that regularly and successively occur at a display frame rate sufficiently high that brightness flicker is acceptably low to a human observer; an x-ray source that can be gated on for intervals not as long as a display frame; and a fluoroscopic camera, including a raster-scanning video camera and x-ray-to-light conversion apparatus with persistence not appreciably longer than a display frame and frame-filling apparatus. Especially during purely diagnostic procedures, the frame-filling apparatus generates a continuous succession of frames of image samples at the display frame rate by interpolating between successively grabbed frames of image samples.

Abstract: A temperature compensation method for a turbidity sensor in an appliance for washing articles is provided. The method includes the steps of: measuring temperature and turbidity of a liquid, such as water, for washing the articles, calculating a turbidity value corresponding to a predetermined reference temperature; and adjusting the measured turbidity of the liquid with respect to the calculated turbidity value so as to provide a temperature compensated turbidity measurement. The method can further include the step of measuring temperature and turbidity of substantially particle-free liquid. This allows for calculating a normalized turbidity value which is substantially free or independent from temperature variation effects.

Abstract: An interferometric switch for spatially switching either linearly polarized or unpolarized externally derived beams of substantially coherent light includes an optical input unit for dividing an externally derived light beam into a constituent beam pair. An optical phase modulating device includes a nematic liquid crystal pixel for selectively shifting the relative phase of the constituent beam pair. An output unit cooperates to combine respective components of the constituent beam pair along coincident collinear paths so as to form a respective output light beam directed along a selected one of first and second output axes, according to the relative phase imparted by the phase-modulating device. The phase modulating device may comprise a cascading arrangement of pixel stages which can respectively provide a selected incremental phase-shift to each constituent beam passing therethrough.

Abstract: A decimation filter for filtering an externally derived stream of quantized electrical signals includes a coefficient generator responsive to a set of externally derived decimation-ratio select signals to provide a separate normalized coefficient signal at each respective one of a plurality of output ports. The coefficient generator employs a zero-fill circuit comprising first and second circuits which selectively ripple therethrough an scaling-control output signal from a demultiplexer unit in order to provide the normalized coefficient signals. An accumulator is coupled to the coefficient generator to receive each normalized coefficient signal generated therein. The accumulator receives the stream of quantized electrical signals so as to produce, upon masking with respective ones of the received normalized coefficient signals, a plurality of accumulator output signals. An overflow detector is coupled to the accumulator to detect and correct any overflow condition arising in the accumulator.

Abstract: A current sensor for measuring a primary electrical current inducing a primary magnetic field defined over a known region includes a first sensor unit for measuring the line integral of the primary magnetic field along a first predetermined path included within the known region; and a second sensor unit for measuring the line integral of the primary magnetic field along a second predetermined path within the known region, the line integral of the primary magnetic field measured by the second sensor unit being a predetermined calibrated amount different from the line integral of the primary magnetic field measured by the first sensor unit. The current sensor further includes a current source for generating a current inducing a magnetic field to partially offset the difference between the line integral of the primary magnetic field measured by the first sensor unit and the line integral of the primary magnetic field measured by the second sensor unit.

Abstract: Techniques and system for pre-processing cone beam projection data for reconstructing substantially free of interpolation-induced artifacts a three-dimensional computerized tomography (CT) image of a portion of an object are provided. Such techniques include identifying first, second and third regions on a surface array detector such that only cone beam projection data acquired in the identified regions is retained for subsequent processing. The identified regions cooperate to eliminate interpolation effects upon lines of integration situated relatively close to boundaries on the array detector and thus allow for reconstructing the substantially free of interpolation-induced artifacts CT image.

Abstract: A memory storage verification device for use with a memory storage unit in which electrical signals stored in selected memory locations are periodically accessed by an external processor. The device includes a register for storing the address of a memory location in the memory storage unit having a stored electrical signal, a comparator for comparing the address stored in the register with an electrical signal from the memory storage unit providing the address of the memory location being accessed by the external processor, and a latch including a trigger coupled to the output port of the comparator. The input port of the latch is coupled to the memory storage unit and receives the electrical signal stored in the memory location being accessed when the trigger receives a signal from the comparator.

Abstract: An electro-optics current sensing system for sensing and avoiding thermally induced measurement errors in a current sensor includes a beam generator, such as a light emitting diode or a laser diode, thermally coupled to the current sensor for encoding into the optical beam supplied by the beam generator both temperature and sensed current information. An electro-optics (E/O) demodulator which includes a wavelength division multiplexer (WDM) demodulates the encoded optical beam to recover the temperature and sensed current information from a pair of demodulated signals which can be further processed for filtering resistivity changes from the sensed current measurement.

Abstract: An ultrasonic transducer with a magnetostrictive lens for dynamically focussing and steering a beam of ultrasound energy is provided. The magnetostrictive lens is operable in response to a magnetic field generated by a coil such that the speed of propagation of the ultrasound beam is selectively controlled as the beam passes through the lens. The lens can be made up of first and second prisms wherein at least one of such prisms is magnetostrictive. Alternatively, the lens can be made up of an individual stage made of a composite having a plurality of elongated rods of magnetostrictive material cooperating in response to the control signal applied to the lens for selectively controlling the propagation speed of the ultrasound beam passing therethrough.

Abstract: An alternating current sensor for measuring a primary alternating current inducing a magnetic flux density defined over a known region comprises: a first sensor for measuring changes in magnetic flux due to the primary current over a first predetermined area included within the known region; a second sensor for measuring changes in magnetic flux due to the primary current over a second predetermined area within the known region, the changes in magnetic flux measured by the second sensor being a predetermined amount different from the changes in magnetic flux measured by the first sensor; and a current source for generating a current inducing changes in magnetic flux over a third predetermined area to offset the difference between the changes in magnetic flux measured by the first sensor and the changes in magnetic flux measured by the second sensor.

Abstract: An alternating current sensor employing a mutually-inductive current sensing scheme comprises a conductive pipe and a cylindrical-shaped conductive element at least partially surrounded by the pipe. The pipe is substantially concentric to the conductive element and a conductor electrically connects a pair of corresponding ends of the pipe and conductive element to form a connected conductive path through the sensor. The conductive element may include a passage or opening shaped to form a magnetic field within the passage during current flow along the conductive path.

Abstract: A noninductive shunt current sensor includes a cylindrical-shaped conductive element and a concentric conductive pipe electrically connected at one end by a conductor, such as a washer. Except for the conductor, the pipe and conductive element are electrically isolated from each other by insulation, such as a polyimide or an air-gap. Sensing wires are electrically connected to contact points, each contact point being located on either the inner surface of the inner pipe or the outer surface of the outer pipe. The wires pass through a space where the magnetic field is substantially null, thereby minimizing any mutual coupling effects. A magnetic core and a coil can be situated between the pipe and the conductive element to provide an electrical self-power capability to the noninductive shunt current sensor.

Abstract: A programmable length decimation filter responsive to an externally derived stream of quantized electrical signals arriving at a predetermined rate comprises a counter, a resolution filter, and an accumulator. The resolution filter is responsive to the counter output signals, to an externally derived resolution select signal, and to the stream of quantized signals, and operates to mask selected quantized signals in order to provide resolution filter output signals to the accumulator on a plurality of resolution filter output ports. The resolution select signal allows for providing flexibility of operation regarding the tradeoff of the bandwidth of the decimation filter with its resolution capability.