Abstract: Disclosed is a smart lead comprising a large number of micro-electrodes and macro-electrodes. The macro-electrodes are perforated, and contain several through-holes which are used to electrically join them with associated electrode-wires. The radial gaps that separate the macro-electrodes are filled with macro-electrode strips that carry a three-dimensional array of micro-electrodes. The nest of macro-electrodes with electrode-wires and micro-electrode strips are injection molded to form the smart lead. The signals sensed by micro-electrodes are used to locate the target neurons right at the first insertion of the smart lead, thereby greatly reducing the surgical time. A closed loop control software in automates location of the target neuron sites and limit the currents to stimulate only the target neurons, thereby reducing side-effects and increasing battery life.

Abstract: The end windings in the stator and rotor are major sources of core-end heating in large electric machines. This invention discloses a Stealth End Winding that makes some of the end-turns within these end windings to be magnetically invisible or stealth in order to reduce the core-end heating. It employs permanent magnets in proximity of these end windings to flip the magnetic field of stealth end-turns, making them to point in a direction away from the core-end. This action reduces the magnetic field that hits the core-end, which in turn reduces core-end heating. A Stealth End Winding can potentially eliminate prevailing devices such as the flux shield, flux shunt, core-end stepping, slit-teeth etc that have been used so far to reduce the core-end heating. Elimination of core-end stepping reduces the field current thereby increase the efficiency and power rating. Elimination of flux shield reduces cost and cooling needs.

Abstract: This disclosure describes a Wearable Magnetic Stimulator to treat a variety of disorders. The device comprises a wearable stimulator head and a wearable stimulator controller. The patient wears the stimulator head over skin close to the target nerves and carries the wearable controller in his clothing. The wearable head comprises a small gapped cut-core energized by coil windings. The head operates on the principle that its small gap injects fringe flux into target nerves, which induces ionic currents that cure disorders. Small gapped cores require significantly smaller current than large gapped cores. This greatly reduces the size and weight of the head and controller. The wearable controller, such as a cell phone, comprises pulse generator hardware and software from internet. The wearable stimulator can be used to treat several disorders such as migraine headache, arthritis, incontinence, depression, erectile dysfunction etc.

Abstract: The invention discloses an insulation system for a stator bar in high voltage electric machines, comprising an anti-corona tape that is wound uniformly and continuously over the entire length of a bare bar. The anti-corona tape comprises a thin resistive sublayer engaged to a thick insulative sublayer. The insulative sublayer provides resistance against high voltage. The resistive sublayer protects the insulation against partial discharges. These partial discharges can occur in voids, such as delamination voids, transposition crossover gaps, strand corners, slot voids, overlap voids etc. The resistive sublayer also increases the thermal conductivity hence reduces the operating temperature. Such insulation using a single-tape approach can replace several layers used in prior-art, viz., an internal corona protection layer, an external corona protection layer, a stress-grading layer and mica layers. This single-tape approach also simplifies the process of manufacturing the stator bar and reduces its cost.

Abstract: A keybar or clamping bolt with a high-resistivity coating to protect an electric machine. The coating engages the laminations, flanges and frame rings and forms a part of electrical circuits through which harmful eddy currents circulate. One class of eddy currents, viz., core-fault currents, due to edge burrs or insulation defects, are forced to flow through this coating. The high resistance of the coating weakens the fault currents, preventing creation of hotspots that can cause core failure. Such coated keybar is in inexpensive alternative to traditional recoating and/or core-fault detection. Another class of eddy currents, viz., keybar currents, caused by over-fluxing, are also forced to flow through this coating. The high resistance of the coating weakens the keybar currents, so prevents core-end overheating. A coated keybar also allows the machine to operate at higher leading power factor. It also prevents core-decompression hence protects the machine against loose laminations.

Abstract: An insulation tester for measuring the surface resistivity of a coated electrical steel sheet using a cylindrical electrode that tests the entire surface area of the sheet. A specific voltage is applied across the insulative coating of the electrical steel sheet using the rotatable cylindrical electrode. The cylindrical electrode is roved over the entire surface of the coated electrical steel sheet to detect insulation defects. This roving tester can be used to locate insulation defects in the coating that can cause core failures, or measure the surface resistivity or dielectric strength of the insulative coating. This tester improves over a conventional Franklin tester which uses discrete button electrodes to test only a small portion of the sheet.

Abstract: The invention provides for flux-shields wrapped around the flux-sources at the core-end of large power generators. They prevent overheating of all core-end parts under all abnormal conditions of operation. A first flux-shield is an electrically conductive cylindrical shell concentric with rotating end-windings, held outside the retaining ring. The rotating flux source induces eddy currents in the first flux-shield whose flux repels the source flux. Only a small part of the rotating source flux is hence received by all the core-end parts, thereby greatly reducing their temperatures. A second flux-shield comprises an electrically conductive tape wrapped over the ground-insulation of stator bars protruding from the core. Alternating flux generated by the stator bars induces eddy currents in the second flux-shield whose flux repels the source flux. Only a small fraction of the source flux is hence received by all core-end parts, thereby greatly reducing their temperatures.

Abstract: The keybar that is attached to the frame of a dynamoelectric machine is broken into a bald keybar with mini-dovetails attached to it. The bald keybar is identical to the bolt portion of a conventional keybar. The mini-dovetail is a trapezoidal or U-shaped strip with insulated slanted arms. The core packet is inserted loosely over an array of mini-dovetails. Devices such as wedges, threaded rods flex the slanted arm and press them against the slot faces of the core packet, thereby locking the core packet to the frame. Insulation on the slanted arms prevents large eddy currents due to shorted laminations, increasing the machine efficiency. Preventing large eddy currents also eliminates hot spots which could otherwise cause a core failure. Locking the core packets also prevents rattling of laminations. The locking method also distributes the torque forces evenly around the periphery.

Abstract: A method of manufacturing a stator bar in large dynamoelectric machines, with the bar insulation made of solid materials with high thermal conductivity and high dielectric strength. In the present invention, the bar insulation is provided by thermally conductive shells whose inner cavity conforms to the bar stock. The manufacturing process comprises slipping one or more thermally conductive shells at the substantially central straight portion of the bar stock, bending the ends of the bar stock to form end-arms, insulating the end-arms with tape or extrusion insulation and bonding all members to form a solid stator bar. In short, the bent end-arms are insulated by the tape or extrusion insulation while the straight portion of the bar is insulated by the thermally conductive shells. This greatly increases the effective thermal conductivity of the stator bar. The high dielectric strength of the materials significantly reduces the wall thickness of the bar insulation.

Abstract: A high power, high frequency toroidal inductor is broken into four quadrant cores and uses bare rectangular conductors to form coils. One coil is wound centrally around each quadrant. The coils positioned centrally on the quadrants minimize the effect of damaging fringe flux and leakage flux. The coil inner winding ends are bent perpendicular to the coils to form tangential leads with one coil inner tangential lead joined to an adjacent outer coil radial lead by jumpers that span adjacent coils.

Abstract: A motor with three gaps produces higher torque than existing one or two gap motors. The motor uses both one radial and two axial gaps to produce torque. A single stator is provided with an essentially “U” shaped rotor shell having permanent magnets with back iron. The stator has loops of coil windings separated by pole pieces. Current flowing in three segments of the coils interacts with the fields from the permanent magnets to produce more torque. The plane of the coils extends through the centerline of the stator. In a given plane through the motor axis, the same polarity of the magnets on the rotor face the stator.

Abstract: An arrangement for cooling an electric motor's stator winding coil is described. One area of a conductor insulation is removed to expose the copper conductor. The conductor is wound into a coil with bared, exposed conductor areas facing inward. The vertical edges of a slot or recess in an iron stator are lined with electrically insulating paper. A thermally conductive electrically insulating, ceramic substrate is bonded to the floor or base of the slot. The coil is inserted within the slot over the ceramic substrate with the exposed conductor facing and contacting the ceramic substrate. The coil is bonded to the ceramic substrate by thermally conductive and electrically insulative epoxy that fills the voids between the two. Heat flows from the conductor, through the bared copper surface, into the ceramic and the iron core stator with little resistance. A ceramic strip can be used alone or with copper traces bonded to the ceramic or conductor bared surface.

Abstract: A brushless motor with axial air gaps is rotated at speeds higher than that of conventional motors by using magnets adjustable in the radial direction. The axial gap machine includes one or more stators, containing windings that conduct electrical currents, and one or more rotors, with sets of permanent magnets rotating on a shaft adjacent the stators. The magnets are supported by bearings in a magnet carrier on the rotor so that the magnets can move radially under the action of centrifugal force opposed by springs. The radial movement of the magnets reduces the number of lines of flux of the magnets that can interact with those created by the electrical currents flowing in the windings. Reducing the flux interaction allows an increase in the speed capability of the machine. Linear radial guides inside the magnet carrier restrict movement of the magnets in all directions other than the radial direction and stops limit outward and inward movement.

Abstract: The torque produced by an electric machine of the axial air gap type is increased by pressing or forming the active sectors of the radial coil sections, essentially coplanar, and by using nonuniform cross-section conductors for the radial active sectors of the coils. One of the active sectors of a leading radial coil section and one of the active sectors of a trailing radial coil section are confined within the central open area formed in a first coil. The gap required between the permanent magnets of rotors, necessary to accommodate the axial thickness of a stator, is reduced to little more than the axial thickness of a single radial section of a stator coil in the active area of the coil. The stator coils can be made by joining winding sheets together. The winding sheets can be made by forming coils from flat, thin conductor coils on carrier films.

Abstract: The torque produced by an electric machine of the type generally known as an axial air gap motor or generator is increased by using nonuniform conductor wires in the stator phase coils in the areas of the coil where the conductor wires extend radially outwardly from and where they extend radially inwardly toward the center of rotation, i.e. that portion of the coil regarded as the active sectors of the coil. The tapered conductor wires enable the total number of wires employed in a phase coil to be doubled by determining the number of wires that can be used at the median radius of the coil rather than at the inner radius. The tapered conductor extends to cover a greater area within the bounds of the coil. With the tapered width designed to extend and increase radially outwardly from the center of rotation, essentially all the surface area within the windings of the coil can be covered by the conductor wires. Only the insulation areas between the wires is not covered by the conductor wires.

Abstract: An electromagnetic disk pump which has a reciprocating member in the form of a rigid ferromagnetic disk. An elastomeric spring, in the form of a short cylindrical tube, is interposed between the reciprocating disk and an electromagnet. The elastomeric spring seals the space between the rigid disk and the electromagnet, thus forming the pump chamber. The electromagnet is used to vibrate the reciprocating disk thereby pumping the fluid contained within the pump chamber. Check valves regulate the fluid flow through the inlet and outlet of the pump chamber.

Abstract: The apparatus includes a resilient mounting for the damping of magnetic bearings. This mount may include a resilient material placed between the magnetic stator and the fixed structure to damp vibrations of the stator induced by variations in the position of the shaft and rotor of the bearing. Alternatively, the resilient material may be placed between successive concentric magnetic rings of the stator. The resilient material is typically an elastomer or a woven metal material with both stiffness and damping properties. The mounting also may consist of separate spring and damping elements. The spring elements can include thin rods or bars which provide both alignment and stiffness. The damping element may consist of a resilient material or a device to provide damping through viscous or mechanical friction configurations.

Abstract: Supercurrent bearings make use of high temperature superconducting coils to support a loaded rotor against radial or thrust loads. One such bearing is an electrodynamic bearing in which superconducting coils are used on both the stator and the rotor to develop a repulsive force. Current is induced in the rotor coils by current supplied to stator coil. Another bearing is an active magnetic bearing in which both superconducting and non-superconducting coils are used on the stator, while the rotor has a laminated secondary to develop attractive forces. The superconducting coils are used for biasing or static loads while the standard (non-superconducting) coils are used for balancing dynamic loads. The high current density of superconductors translates to higher load capacity, smaller bearing size and a lighter bearing.

Abstract: A fatigue test apparatus in which a specimen to be tested is attached at its ends to a pair of opposing pistons positioned within a pair of opposing cylinders. The cylinders are attached to a support frame such that the specimen is oriented substantially vertically. In a preferred embodiment, the specimen is enclosed in a heat chamber to test at high temperatures. Each of the pistons is attached to a shaft having a weight at its end and the weights are drivingly connected to a pair of shakers which are actuated to vibrate 180.degree. out of phase with each other. The cylinders are pressurized to exert a static tensile load on the specimen, and the shakers are actuated to exert a dynamic tensile load which is superimposed on the static load and travels through the weights, shafts and pistons to the specimen.