159results about How to "Increase flux density" patented technology

A composite magnetic core formed of a high permeability material and a lower permeability, high saturation flux density material prevents core saturation without an air gap and reduces eddy current losses and loss of inductance. The composite core is configured such that the low permeability, high saturation material is located where the flux accumulates from the high permeability sections. The presence of magnetic material having a relatively high permeability keeps the flux confined within the core thereby preventing fringing flux from spilling out into the winding arrangement. This composite core configuration balances the requirements of preventing core saturation and minimizing eddy current losses without increasing either the height or width of the core or the number of windings.

A vehicle seat inductive charger and data transmitter system includes: a vehicle seat having a first inductive coil, apparel having therein a second inductive coil, a first charging and controlling circuit cooperating with the first inductive coil, and adapted to energize and modulate the first inductive coil to transfer power and data to the second inductive coil solely via inductive coupling between the first and second inductive coils, a second charging and control circuit on the apparel cooperating with the second inductive coil, at least one main battery adapted for wearing by the user, where the main battery is adapted for charging by the second circuit upon the inductive coupling of the first and second inductive coils when energized.

An inductive energy harvester comprises a permanent magnet magnetic field source attached by a pair of compact spiral disk springs to an induction coil. The springs position the magnet so that the induction coil surrounds one end of the magnet where the flux density is greatest. In addition, the magnetic flux emerging from that end of the magnet is enhanced by a disk of magnetic material having high permeability and high flux density. In another embodiment, the magnetic field source comprises two dipole magnets arranged in opposing flux relationship with a thin layer of high flux density, high magnetic permeability material located in a gap between the magnets.

A perpendicular magnetic recording disk having a single domain exchange-coupled laminated soft magnetic underlayer (SUL) is disclosed. The SUL is a combination synthetic anti-parallel coupled SUL structure, which has the product (Mst) of saturation magnetization and film thickness of the middle ferromagnetic layer less than the sum of the Mst of the bottom and top ferromagnetic layers. Subjected to a post radial field reset process, this SUL provides single domain state. Moreover, both robustness of stray fields and low permeability are obtained while keeping excellent corrosion resistance and cost effective manufacturability.

A rotor-stator structure for electrodynamic machinery is disclosed to, among other things, minimize magnetic flux path lengths and to eliminate back-iron for increasing torque and/or efficiency per unit size (or unit weight) and for reducing manufacturing costs. In one embodiment, an exemplary rotor-stator structure can comprise a shaft defining an axis of rotation, and a rotor on which at least two magnets are mounted on the shaft. The two magnets can be cylindrical or conical magnets having magnetic surfaces that confront air gaps. In some embodiments, substantially straight field pole members can be arranged coaxially and have flux interaction surfaces formed at both ends of those field poles. Those surfaces are located adjacent to the confronting magnetic surfaces to define functioning air gaps, which are generally curved in shape.

A reflector for a liquid crystal display includes a substrate with light-reflective concave portions on the surface thereof. Each concave portion has a specific vertical section which passes through a deepest point of the concave portion. The internal shape of the specific vertical section is defined by a first curve, which extends from one point on the peripheral edge of the concave portion to the deepest point of the concave portion, and a second curve, which extends continuously from the first curve and from the deepest point of the concave portion to another point on the peripheral edge of the concave portion. The average of the absolute value of an inclination angle of the first curve relative to the substrate surface is larger than the average of the absolute value of an inclination angle of the second curve relative to the substrate surface.

A valve actuator for an internal combustion engine is described having a core having a wound coil located therein, said core further having at least one permanent magnet located at least partially inside or outside said coil and positioned at an angle relative to a direction of movement of an armature. Further, various recesses, indentations, chamfers, bevels, and/or depressions may be included to affect flux leakage, and/or force generation.

The present invention provides a novel use of a powdered high saturation flux density soft magnetic material as a NMR probe core material. The probe structural geometry facilitates the use of powdered material, which has a relatively low magnetic permeability.

Disclosed are various embodiments for a motor/generator comprising: a rotor adapted to rotate about a longitudinal axis, the rotor comprising a first partial toroidal magnetic cylinder defining a semi-circular tunnel, wherein the plurality of magnets forming the first partial toroidal magnetic cylinder have substantially all like poles facing inward toward the semi-circular tunnel, the semi-circular tunnel having an entrance and an exit forming an open throat defined by a space between the entrance and the exit, and a stator positioned about the longitudinal axis within a rotational path of the rotor.

A superconducting electrical machine has rotor and stator assemblies. A first rotor assembly is located to rotate within a stator assembly and is spaced from the stator assembly by an air gap. A second rotor assembly is located to rotate outside the stator assembly and is also spaced from the stator assembly by an air gap. The first and second rotor assemblies have at least one superconducting field winding. The superconducting field windings are formed from a High Temperature Superconducting (HTS) material such as BSCCO-2223 or YBCO, for example. The double rotor assembly configuration provides a new technical effect over conventional rotating superconducting machines having a single rotor assembly.

Two TE modes whose electric-field rotating planes have a perpendicular relationship are coupled independently of the coupling between two TM modes whose electric-field directions have the same respective perpendicular relationships. In a multimode dielectric resonator device producing four modes: TM01δ_x mode, TM01δ_y mode, TE01δ_x mode, and TE01δ_y mode, protrusions (Pe1), (Pe2) are disposed on an upper-layer (La) and a lower-layer of a dielectric core (1) to cause a difference in effective dielectric constants of individual parts through which even-mode and odd-mode electric flux of the TE coupling modes passes. A protrusion (Pc) is formed on a middle-layer Lb of the dielectric core (1) such that the effective dielectric constants of the parts through which even-mode and odd-mode electric flux of the TM coupling modes pass become substantially equal. Thereby, the TE01δ_x mode and TE01δ_y mode are coupled while restraining the coupling of the TM01δ_x mode and the TM01δ_y mode.

A giant magnetoresistive flux focusing eddy current device effectively detects deep flaws in thick multilayer conductive materials. The probe uses an excitation coil to induce eddy currents in conducting material perpendicularly oriented to the coil's longitudinal axis. A giant magnetoresistive (GMR) sensor, surrounded by the excitation coil, is used to detect generated fields. Between the excitation coil and GMR sensor is a highly permeable flux focusing lens which magnetically separates the GMR sensor and excitation coil and produces high flux density at the outer edge of the GMR sensor. The use of feedback inside the flux focusing lens enables complete cancellation of the leakage fields at the GMR sensor location and biasing of the GMR sensor to a location of high magnetic field sensitivity. In an alternate embodiment, a permanent magnet is positioned adjacent to the GMR sensor to accomplish the biasing. Experimental results have demonstrated identification of flaws up to 1 cm deep in aluminum alloy structures. To detect deep flaws about circular fasteners or inhomogeneities in thick multilayer conductive materials, the device is mounted in a hand-held rotating probe assembly that is connected to a computer for system control, data acquisition, processing and storage.

The present disclosure provides a brushless permanent magnet machine which includes an essentially circular shaped rotor, and a pair of magnets arranged in the rotor. The magnets are each U-shaped and have a thickness direction extending along a contour of the corresponding magnet between the opposite poles of the corresponding magnet, respectively. The magnets are each composed of a non-rare earth material having a lower coercivity than a rare earth material. A direction of magnetization of each of the pair of magnets is parallel to the thickness direction of the corresponding magnet. The present disclosure also provides a method of manufacturing such a brushless permanent magnet machine.

Numerous arrangements for permanent magnets are disclosed that can focus the flux produced by the magnets. Depending on the particular application in which the disclosed designs and techniques are used, efficiency and reliability may be increased by minimizing flux leakage, increasing peak flux density, and shaping the flux fields to improve the effective coercivity of the flux focusing permanent magnet arrangement when loaded, and to achieve customized voltage and current waveforms. The disclosed magnet assemblies may be incorporated into a machine, such as a motor/generator, having windings and may be disposed for movement relative to the windings. The magnet assembly may be mounted on a support formed of one or more ferromagnetic materials, such as a back iron The disclosed flux focusing magnet assemblies may be formed using a variety of manufacturing methods.

The machine in accordance with the present disclosure is an AC machine whose pole numbers can be switched (from pole p₁ to pole p₂), and whose number of series turns per phase N can be switched say from N₀=N_rated to N₁=N₀/2. Furthermore, it employs an inverter so that the frequency can be changed from a low value (e.g., 5 Hz) to a high value (e.g., 200 Hz). Due to the combination of pole number and number of series turns switching/reconfiguration, a high torque at low speed (e.g., 0 rpm) and a high torque at high speed (e.g., 5,000 rpm) can be achieved, making mechanical gears obsolete. In addition, the output power of the motor can be increased at high speed in direct proportion to the speed increase.

Systems for x-ray illumination that have an x-ray brightness several orders of magnitude greater than existing x-ray technologies. These may therefore useful for applications such as trace element detection or for micro-focus fluorescence analysis. The higher brightness is achieved in part by using designs for x-ray targets that comprise a number of microstructures of one or more selected x-ray generating materials fabricated in close thermal contact with a substrate having high thermal conductivity. This allows for bombardment of the targets with higher electron density or higher energy electrons, which leads to greater x-ray flux. The high brightness/high flux x-ray source may have a take-off angle from 0 to 105 mrad. and be coupled to an x-ray optical system that collects and focuses the high flux x-rays to spots that can be as small as one micron, leading to high flux density.

The present invention relates to a miniature electro-acoustic transducer including a magnetic circuit, a diaphragm and a voice coil operatively connected to the diaphragm. The magnetic circuit includes first and second air gap portions adapted to receive first and second voice coil segments, respectively. The magnetic flux acting on the first voice coil segment is provided by inner magnetic means and first outer magnetic means in combination and the magnetic flux acting on the second voice coil segment is essentially provided by the inner magnetic means only.

Disclosed are various embodiments for a motor/generator where the stator is a coil assembly and the rotor is a magnetic toroidal cylindrical tunnel or where the rotor is a coil assembly and the stator is a magnetic toroidal cylindrical tunnel.