2688 results about "Magneto" patented technology

Apparatus and method for wireless near-field magnetic communication (NFMC) of information (e.g., voice or data) over modest distances (centimeters to a few kilometers). The transmission can proceed from an inductive coil transmitter to a magneto-electric (ME) receiving device, or between two ME devices. Electrical power may also be transmitted from and/or received using the same device. In one case, power and data are transmitted from an induction coil to a distant ME device that collects power and transmits data back to the power-transmission coil. In another case, the wireless transfer of data can be carried out between two ME devices. ME devices can be engineered to transmit or receive data and to receive electric power over a variety of frequencies by changing their dimensions, their material makeup and configuration, electrode configurations, and/or their resonance modes (longitudinal, transversal, bending, shear etc). Data rates up to and above several kilo-bits/s are possible using these methods with no limits on the frequency and duration of the communication.

The present invention provides a tunneling magneto-resistive read sensor structure that improves sensitivity and linear density of the sensor structure. The sensor includes first and second electrodes and a stack positioned between the electrodes. The stack includes first and second free layers with magnetization orientations that are biased relative to each other. A tunneling barrier (insulating layer) or non-magnetic metal spacer is positioned between the first and second free layers. A sense current is passed between the first and second free layers of the stack. The amount of current passing through the first and second free layer changes based upon the orientation of the first and second free layers relative to each other.

Provided herein are systems, methods, and compositions for the use of optical coherence tomography for detection of cells.

A circuit arrangement for correcting magneto-resistive head asymmetry includes a shift circuit which receives a read signal from a magneto-resistive head, and a polarity signal indicative of the polarity of any asymmetry of the read signal. Depending on the polarity of the asymmetry, the shift circuit either adds or subtracts a shift voltage to the read signal to produce a shifted read signal. The shift circuit outputs the read signal, the shifted read signal, and the shift voltage. First, second and third gain circuits are provided, which receive the read signal, the shifted read signal, and the shift voltage, respectively, and which each receive a respective control signal. The first, second and third gain circuits provide respective outputs amplified proportionally based on the respective control signals. Control circuitry provides the polarity signal to the shift circuit and the respective control signals to the first, second and third gain circuits, based on an amount of correction required. A common-mode-feedback circuit adjusts for changes in the common-mode caused by the waveform shaping.

An apparatus having a coil of wire, energized by a repetitively pulsed radio frequency (RF) power source to provide electromagnetic fields to a region within a body. A scanning, directional hydrophone acoustically connected to the body, samples ultrasonic radiation generated by the RF fields at the RF frequency or twice the RF frequency induced from conductive spots. Signals from the hydrophone are analyzed with regard to their time of arrival relative to the RF pulses and with respect to their direction of arrival. These collected data are recorded and displayed as images of the spots within the region.

A magneto-caloric (MC) device is disclosed. The MC device comprise a rotor, a housing disposed about and concentric with the rotor and mechanically coupled to the rotor, wherein the housing comprises at least one axial slot, at least one set of MC elements, wherein each set of MC elements comprises at least one MC element, and at least one MC element of each set of MC elements is disposed within each of the at least one axial slots, and at least one working-segment corresponding to each set of MC elements, wherein each working-segment is disposed axially around the rotor and external to the housing, and wherein each working-segment comprises, a yoke substantially defining an inner volume comprising a first inner volume and a second inner volume, and a magnetic field production (MFP) unit magnetically coupled to the yoke and configured to provide a magnetic field within the first inner volume.

Products are disclosed for measuring electromagnetic fields. One embodiment has at least two coplanar magneto-resistive sensors. Each magneto-resistive sensor has a sensitive axis in the plane of the at least two coplanar magneto-resistive sensors. The at least two magneto-resistive sensors may be orthogonally arranged about a central point to measure orthogonal components of electromagnetic fields.

A magneto-active adhesive and method of adhesive bonding by magnetic field. The method includes steps of providing at least two adherends to be bonded, providing a magneto-active adhesive system between the at least two adherends, the magneto-active adhesive system comprising a plurality of magnetic particles and an adhesive; and applying a non-cyclically varying magnetic field or a cyclically varying magnetic field induced by an alternating current having a frequency of less than 100 hz to the magneto-active adhesive system to change the adhesion of the magneto-active adhesive system to at least one of the adherends. Various carriers for microelectronic devices including magneto-active adhesive contact surfaces are also described within the scope of the invention.

A micro-electromechanical system (MEMS) based current & magnetic field sensor includes a MEMS-based magnetic field sensing component having a capacitive magneto-MEMS component, a compensator and an output component for sensing magnetic fields and for providing, in response thereto, an indication of the current present in a respective conductor to be measured. In one embodiment, first and second mechanical sense components are electrically conductive and operate to sense a change in a capacitance between the mechanical sense components in response to a mechanical indicator from a magnetic-to-mechanical converter.

A heat pump system that uses variable magnetization to control the amount of MCM subjected to a magnetic field is provided. More particularly, the amount of MCM subjected to a magnetic field can be selected based on the amount of refrigeration needed. As such, the heat pump system can be adjusted based on e.g., changes in ambient conditions, and the energy used in operating such a heat pump system can be conserved so as to increase energy efficiency of the system.

The invention concerns a position sensor, designed in particular for detecting a steering column torsion, consisting of a first magnetic structure including a plurality of magnets and a second magnetic structure including two ferromagnetic rings (6, 7) having a plurality of teeth (11, 12) and defining an air gap wherein is placed at least a magneto-sensitive element (15), the two magnetic structures being respectively integral with two parts in relative rotation. The invention is characterised in that the two ferromagnetic rings (6, 7) are nested and have each a substantially tubular part forming axially oriented teeth (11, 123) connected by a flux-closing zone (13, 14), the detecting air gap being delimited by said flux-closing zones.

An angular sensor which enables to obtain an output signal proportional to a relative rotational angle with low manufacturing cost and with miniaturized size. An angular sensor which includes a first magnet and a second magnet fixed to a rotation body, magnetic flux sensing surface is fixed to the stator to be positioned in magnetic field between the first magnet and the second magnet and perpendicular to magnetic sensing direction for sensing a magnetic flux, a magneto-electric transducer element for outputting an electric signal corresponding to a magnetic sensing direction element of the magnetic density, deflection yokes. The deflection yokes are positioned facing the magnetic flux sensing surfaces. The deflection yokes are positioned within a range of three quarters of a distance between the first magnet and the second magnet in X-axis direction and one half of a distance between the first magnet and the second magnet in Y-axis direction.

A tunneling magneto-resistive reader includes a sensor stack separating a top magnetic shield from a bottom magnetic shield. The sensor stack includes a reference magnetic element having a reference magnetization orientation direction and a free magnetic element having a free magnetization orientation direction substantially perpendicular to the reference magnetization orientation direction. A non-magnetic spacer layer separates the reference magnetic element from the free magnetic element. A first side magnetic shield and a second side magnetic shield is disposed between the top magnetic shield from a bottom magnetic shield, and the sensor stack is between the first side magnetic shield and the second side magnetic shield. The first side magnetic shield and the second side magnetic shield electrically insulates the top magnetic shield from a bottom magnetic shield.

The present invention describes the design and fabrication of Multi-Material-Blades used as active regenerative regenerators in active regenerative magneto-caloric or electro-caloric engines. The blades consist of a plurality of elements (2) that divide the blade body along its length. Each element (2) is made of a different magneto-caloric or electro-caloric material selected appropriately, and a plurality of dedicated channels (3) penetrates the blade body (1) and extends along the length of the blade. The dedicated channels (3) can be provided with fluid mixing structures, porous layers or hydrophobic coatings to reduce the HE loss in an active regenerative engine. The Multi-Material-Blades are obtainable by ink jet printing techniques to reduce costs. The Multi-Material-Blades can further have a curved shape to form an involute blade body (1). All measures can improve the performance of active regenerative magneto-caloric or electro-caloric engines, and lay the basis for commercial solutions.

A thermal spring magnetic medium is provided having first and second stacks providing two exchange coupled ferromagnetic layers having different Curie temperatures. The first stack has a high magneto-crystalline anisotropy, a relatively low saturation magnetization and a low Curie temperature. The second stack has a relatively low magneto-crystalline anisotropy, a high saturation magnetization and a high Curie temperature. Preferably the first stack includes an alloy of Fe—Pt or Co—Pt, and the second stack includes an allow of Co—Pt or Co—Pd. A disk drive system having the novel medium is also provided.

A heat pump system is provided that uses multiple stages of MCMs with different Curie temperature ranges. An adjustable fluid flow path is used whereby the number of stages through which a heat transfer fluid passes can be varied depending upon e.g., the amount of heating or cooling desired. In certain embodiments, a magnetic field used to activate the MCMs can be manipulated so that the number of stages of MCMs that are activated also be adjusted. These and other features can improve the operating efficiency of the heat pump.

A magnetic refrigerating device includes: a magnetic refrigerating unit including a magnetic material “A” exhibiting a magneto-caloric effect that the temperature of the material “A” is increased by the application of a magnetic field and the temperature of the material “A” is decreased by the removal of a magnetic field, a magnetic material “B” exhibiting a magneto-caloric effect that the temperature of the material “B” is decreased by the application of a magnetic field and the temperature of the material “B” is increased by the removal of a magnetic field, a heat conductive material “a” exhibiting higher heat conductivity under the application of a magnetic field and lower heat conductivity under the removal of a magnetic field, and a heat conductive material “b” exhibiting lower heat conductivity under the application of a magnetic field and higher heat conductivity under the removal of a magnetic field, wherein the magnetic refrigerating unit is configured so as to include at least one layered structure denoted by “AaBb” or “AbBa”; and a magnetic field-applying means to apply a magnetic field to the magnetic refrigerating unit.

A method of patterning a magnetic tunnel junction (MTJ) stack is provided. According to such method, an MTJ stack is formed having a free layer, a pinned layer and a tunnel barrier layer disposed between the free layer and the pinned layer. A first area of the MTJ stack is masked while the free layer of the MTJ is exposed in a second area. The free layer is then rendered electrically and magnetically inactive in the second area.

A downhole caliper instrument utilizing a magneto resistive sensor to determine the position of a caliper arm which extends to touch the surface of the borehole wall.

A device and method for discovering, identification and monitoring of mechanical flaws in metallic structures is disclosed, based on magneto-graphic/magnetic tomography technique to identify stress-related defects. The technique is specifically optimized for extended, not-accessible underground and underwater metallic structures quality control, emergency alarms as well as timeline planning for structural repairs and maintenance work. Examples of the technique implementation include pipes for oil and gas industry, detection of flaws in rolled products in metallurgical industry, welding quality of heavy duty equipment such as ships, reservoirs, etc. It is especially important for loaded constructions, such as pressured pipes, infrastructure maintenance, nuclear power plant monitoring, bridges, corrosion prevention and environment protection.

A magneto-resistive device has a high reproducing output and is suitable for use as a CPP-GMR device. The magneto-resistive device has a first magnetic layer, a second magnetic layer, and a non-magnetic spacer formed between the first and second magnetic layers. The first magnetic layer contains a magnetic material whose conduction electrons belong to a first energy band, and the second magnetic layer contains a magnetic material whose conduction electrons belong to a second energy band. The first and second energy bands are attributable to orbitals of the same kind, thereby increasing the ratio of change in magnetoresistance and adjusting the electric resistance.

A heat pump system having magneto caloric material positioned in a continuously rotating regenerator is provided. The magneto caloric material is staged so that as the regenerator is rotated, a portion of the material is cycled in and out of a magnetic field in a continuous manner. A heat transfer fluid is circulated through the magneto caloric material simultaneously along at least two paths to provide for the transfer of heat both to and from the material in a cyclic manner. The magneto caloric material may include zones having different temperature ranges of responsiveness to the magnetic field. An appliance using a heat pump system based on magneto caloric material is also provided.

The invention discloses a heat-power conversion magnetism device. The heat-power conversion magnetism device includes a magneto caloric effect material so that the magnetic field thereof can be changed according to the temperature difference. The heat-power conversion magnetism device rotates by changing the magnetic field of the magneto caloric effect material.

A heat pump is provided that uses multiple stages of MCMs to cause heat transfer between a heat receiving end and a heat transmitting end. Thermal blocks are placed along the direction of heat transfer at locations in the heat pump that preclude the transfer of heat in a direction from the heat transmitting end towards the heat receiving end. The heat pump can be, for example, part of a refrigeration loop or can be connected directly with the object for which heating or cooling is desired. An appliance incorporating such a heat pump is also provided.

The utility model provides a back-to-back convertor of a wind power generation system. Two back-to-back convertors are connected in parallel. Each convertor comprises rectifiers on the side of a motor and an inverter on the side of a grid. The rectifiers on the side of the motor are conncted in parallel. An AC input end is connected with an outlet terminal on the side of a stator of a magneto alternator; direct-current output terminals of the two rectifiers on the side of the motor are connected with an independent voltage-stabilizing large capacitor, respectively. A positive terminal and a negative terminal of each of the capacitors are conneted with an inverter, respectively; output terminals of the inverters are connected to a grid after parallel connection. Each rectifier on the side of the motor is controlled by a digital processing chip DSP. When the two convertors run concurrently, circulatory zero-sequence current of the shunt circuit between the convertors is restricted to bezero; circuit loss is accordingly reduced, and circuit components are protected.

A sensor assembly for sensing angular position of an object is provided. The assembly may comprise at least one magneto-sensing element having a first axis of rotation. The assembly may further comprise a magnet having a second axis of rotation. At least one of the magnet and the magneto-sensing element are rotatable relative to the other. The respective axes of rotation of the magneto-sensing element and the magnet are non-coincident with respect to one another. The magnet is magnetized along one of the following directions: an axial direction and a radial direction.

An integrated angular magnetic sensor apparatus for determining a magnetic field angle within two axes of a plane is formed on a substrate onto which two anisotropic magneto-resistive sensing elements and at least one magneto-resistive sensing element are fabricated. The two anisotropic magneto-resistive sensing elements are oriented such that the output voltages of a first and second of the anisotropic magneto-resistive sensing elements are a function of a first and second trigonometric function (a sine function) of the magnetic field angle to a reference axis. The at least one magneto-resistive sensing element on the substrate and having a fixed reference magnetization oriented with respect to the reference axis such that an output voltage of the at least one magneto-resistive sensing element provides a quadrant indicator for the magnetic field angle with respect to the reference axis. The quadrant indicator is a trigonometric function such as a sine or cosine function.

A hard bias (HB) structure for longitudinally biasing a free layer in a MR sensor is disclosed that is based on HB easy axis growth perpendicular to an underlying seed layer which is formed above a substrate and along two sidewalls of the sensor. In one embodiment, a conformal soft magnetic layer that may be a top shield contacts the HB layer to provide direct exchange coupling that compensates HB surface charges. Optionally, a thin capping layer on the HB layer enables magneto-static shield-HB coupling. After HB initialization, HB regions along the sensor sidewalls have magnetizations that are perpendicular to the sidewalls as a result of surface charges near the seed layer. Sidewalls may be extended into the substrate (bottom shield) to give enhanced protection against side reading. The top surface of the seed layer may be amorphous or crystalline to promote HB easy axis perpendicular growth.

A generating device that includes an AC/DC conversion unit having a rectifier circuit that rectifies an output of a magneto rotor and applies the output to a battery, and an inverter circuit that converts a voltage of the battery into an AC control voltage and applies the AC control voltage to an armature coil of the magneto generator, performs chopper control that controls switch elements of the inverter circuit so as to interrupt an output current of the magneto generator to control the output of the magneto generator when a rotational speed of the magneto generator is lower than a set speed, and performs drive control that applies the AC control voltage from the battery through the inverter circuit to the armature coil when the rotational speed becomes higher than the set speed, and changes a phase angle of the AC control voltage to control the output of the magneto generator.

A magnetic field based mechanical apparatus is disclosed. The apparatus is based on coupled attracting or opposing magnets in conjunction with the insertion or removal of a magnetic field modifier. In the preferred embodiment, two repelling magnets are drawn together with the insertion of a magnetic field modifier. The field modifier may be another magnet having an opposing pole. Removal of the field modifier returns the forces to their original states. This oscillating motion may be driven with a low energy and/or small power supply. The resulting motion of the opposing magnets can drive mechanical system such as a linear, gear, ratchet, or reciprocating drive.