Abstract: A dental attachment includes a magnet element delivering a magnetic attraction force, a yoke made of a soft magnetic material and having a recess for housing the magnet element, and a disc consisting of the soft magnetic material and joined to the yoke so as to close the opening of the recess with the magnet element housed in the recess. The yoke has an almost disc shape and has collars protruding radially outwardly from the outer peripheral surface thereof. The collars are formed to be separated in at least two locations in a substantially peripheral direction, and non-protruding portions having radially outward projection amounts of zero or up to 50% of the maximum projection amount at the collars are provided between respective collars.

Abstract: The present invention relates to a method for producing a rare earth anisotropic bond magnet containing a hollow cylindrically shaped magnetic molded body having, at the hollow cylindrically shaped side face thereof, at least 4 or more orientation portions that are oriented with semi-radial distribution by compression molding of a magnetic material after thermally orienting step, wherein intermediate aligning magnetic fields applied in the thermally orienting step to between adjacent cavities are the mostly same in their magnetic directions. A plurality of rare earth anisotropic bond magnets can be efficiently produced at one time.

Abstract: To realize an anisotropic bonded magnet that reduces cogging torque without lowering output torque. The present invention provides a hollow cylindrically shaped anisotropic bonded magnet for use in a 4-pole motor, formed by molding anisotropic rare-earth magnet powder with resin. The alignment distribution of the anisotropic rare-earth magnet powder in a cross section perpendicular to the axis of the anisotropic bonded magnet is in the normalized direction of the cylindrical side of the hollow cylindrical shape in the main region of a polar period, and in a transition region in which the direction of the magnetic pole changes, steadily points towards a direction tangential to the periphery of the cylindrical side at points closer to the neutral point of the magnetic pole, and becomes a direction tangential to the periphery of the cylindrical side at that neutral point, and steadily points toward the normalized direction of the cylindrical side at points farther away from the neutral point.

Abstract: The present invention provides miniaturization of brushless motors and brush motors used in electric devices, a ring magnet which simultaneously achieves both high torque and a reduction in cogging torque, a ring magnet with yoke, and a brushless motor. The thin hybrid magnetized ring magnet of the present invention is structured of, in a ring magnet comprised of a plurality of magnetic poles, a radially magnetized main pole and an interface for which the interface of the adjoining main pole is polar anisotropic. When the thin hybrid magnetized ring magnet structured in this manner is applied to a brushless motor, in the case of radial magnetizing, the abrupt change in magnetic flux of the interface between the magnetic poles becomes smooth and cogging torque is greatly reduced due to polar anisotropic magnetization of the interface.

Abstract: A hollow cylindrically shaped anisotropic bonded magnet for use in a 4-pole motor, is formed by molding anisotropic rare-earth magnet powder with resin. The alignment distribution of the anisotropic rare-earth magnet powder in a cross section perpendicular to the axis of the anisotropic bonded magnet is in the normalized direction of the cylindrical side of the hollow cylindrical shape in the main region of a polar period, and in a transition region in which the direction of the magnetic pole changes, steadily points towards a direction tangential to the periphery of the cylindrical side at points closer to the neutral point of the magnetic pole, and becomes a direction tangential to the periphery of the cylindrical side at that neutral point, and steadily points toward the normalized direction of the cylindrical side at points farther away from the neutral point.

Abstract: The rectifying characteristic of a brush-equipped direct current machine is improved, and the life of the machine is extended. As illustrated in FIG. 2, a magnetic flux density reduced portion in which the magnetic flux density is reduced is formed in a magnetic pole section of an anisotropic bonded magnet. The position in the magnetic pole section formed with the magnetic flux density reduced portion is formed at the position at which, when a rectifier coil moves in a rectification section, the absolute value of the density of a magnetic flux penetrating the rectifier coil is increased due to the influence of the magnetic flux density reduced portion. Thus, an inverse voltage can be induced in the rectifier coil in the direction of inversion current during a rectification period. It is therefore possible to facilitate the inversion of the current, and to compensate for inadequate rectification and improve the rectifying characteristic.

Abstract: An attitude detection sensor includes three magnetic sensing parts that detect magnetic field strength in respective directions along three axes perpendicular to each other, and two tilt sensing parts that detect tilt angles around two axes perpendicular to each other. The tilt sensing parts each include a cantilever having a magnet body that moves in accordance with the tilt angle, and a magnetic detection head that detects a displacement of the magnet body. The three magnetic sensing parts and the two magnetic detection heads are each formed using a magnetic detection element of the same type. At least one electronic circuit for controlling the five magnetic detection elements, the three magnetic sensing parts, and the two tilt sensing parts is disposed in a single package in the form of a module.

Abstract: [Object] To improve resistance of a motor device against an organic solvent and to suppress degradation in performance of the motor device with time. [Solving Means] In a motor device, an excitation magnet is formed using a hollow-cylinder shaped anisotropic bonded magnet 13. This bonded magnet 13 is press-fitted in a housing 12 and is held. The bonded magnet 13 is formed of a hollow-cylinder shaped anisotropic rare earth bonded magnet which is obtained by compounding an anisotropic rare earth magnet powder with a phenol-novolac type epoxy resin, followed by molding. The anisotropic rare earth bonded magnet 13 is press-fitted along an inner peripheral portion of the housing 12, and on an exposed surface layer of the anisotropic rare earth bonded magnet press-fitted in the housing, a coating layer is formed by an infiltration treatment using a polyamide-imide-based resin.

Abstract: A device capable of producing an annular magnet or arcuate magnet with excellent dimensional accuracy and magnet performance, of which the mass is not greatly scattered. The device for producing the annular magnet, for example, includes a preforming section for obtaining an annular preformed body from a compound of a mixture of an anisotropic magnet powder and a thermosetting resin, a magnetic field orienting and forming section for obtaining an annular intermediate formed body by subjecting the annular preformed body to orienting and pressure-forming, a main forming section for obtaining an annular magnet by further forming the annular intermediate formed body, and a work transferring section for transferring works.

Abstract: The bonded magnet of the present invention, in which average particle diameter and compounding ratio are specified, is comprised of Cobalt-less R1 d-HDDR coarse magnet powder that has been surface coated with surfactant, R2 fine magnet powder that has been surface coated with surfactant (R1 and R2 are rare-earth metals), and a resin which is a binder. The resin, a ferromagnetic buffer in which R2 fine magnet powder is uniformly dispersed, envelops the outside of the Cobalt-less R1 d-HDDR coarse magnet powder. Despite using Cobalt-less R1 d-HDDR anisotropic magnet powder, which is susceptible to fracturing and therefore vulnerable to oxidation, the bonded magnet of the present invention exhibits high magnetic properties along with extraordinary heat resistance.

Abstract: A three-dimensional magnetic bearing sensor 10a includes a first sensor 101, a second sensor 102, and a third sensor 103 each constituted by a magneto-impedance sensor element 10 comprising a magnetic sensitive member 2 having a characteristic changed responsive to an external magnetic field, an insulator 4 formed to allow penetration of the magnetic sensitive member 2 therethrough, and an electromagnetic coil 3 made up of foil-like conductive patterns 31, 32 arranged in adjacent relation on an outer surface of the insulator 4. The first sensor 101, the second sensor 102, and the third sensor 103 are disposed such that directions in which the magnetic sensitive members 2 in respective sensors have maximum magnetic field detection sensitivities are substantially orthogonal to each other.

Abstract: A magnetic compass includes: a three-axis magnetic sensor for detecting geomagnetic vector as geomagnetic components in directions of three orthogonal axes x, y, and z; a data-plane calculating unit for calculating a data plane on which output data of the three-axis magnetic sensor are present in a sensor coordinate system of the three axes x, y, and z; a unit vector calculating unit for calculating unit vectors of a horizontal coordinate system of three orthogonal axes X, Y, and Z whose Z-axis runs vertically and X-Y plane defines a horizontal plane relative to the earth; a horizontal coordinate system conversion unit for converting geomagnetic components in the sensor coordinate system detected by the three-axis magnetic sensor into geomagnetic components in the horizontal coordinate system; an azimuth calculating unit for calculating azimuth based on the converted geomagnetic components in the horizontal coordinate system; and a display unit for displaying the calculated azimuth.

Abstract: A magneto impedance sensor element with electromagnetic coil comprised of: a terminal board on which an extended groove which extends in one direction has been formed; an electromagnetic coil, made with one part of the coil formed in a spiral shape inside the extended groove in the terminal board, and joined to each tip of that coil the other part of the coil placed across the top of the groove; insulating material placed in the extended groove on the terminal board; and a magnetic sensitive body inserted within the insulating material, to which either high frequency or pulse electic current is applied. When either high frequency or pulse electrical current is applied to the magnetic sensitive body, voltage is output from the above electromagnetic coil in response to the intensity of the external magnetic field which is generated in the electromagnetic coil.

Abstract: An accelerometer for measuring the displacement of a magnet body using magnetic detecting elements is provided, the accelerometer having superior measurement accuracy by suppressing influence of a peripheral magnetic field. The accelerometer has detecting units each having a cantilever which is elastically deformed so as to rotate around a fixed end thereof, a magnet body provided at a free end of the cantilever, and a magnetic detecting head portion disposed outside the rotation region of the cantilever. In order to correct detection signals output from the magnetic detecting head portions, the accelerometer has peripheral magnetic field detecting portions for measuring a peripheral magnetic field acting on the magnetic detecting head portions and the magnet bodies.

Abstract: A magnetic compass includes: a three-axis magnetic sensor for detecting geomagnetic vector as geomagnetic components in directions of three orthogonal axes x, y, and z; a data-plane calculating unit for calculating a data plane on which output data of the three-axis magnetic sensor are present in a sensor coordinate system of the three axes x, y, and z; a unit vector calculating unit for calculating unit vectors of a horizontal coordinate system of three orthogonal axes X, Y, and Z whose Z-axis runs vertically and X-Y plane defines a horizontal plane relative to the earth; a horizontal coordinate system conversion unit for converting geomagnetic components in the sensor coordinate system detected by the three-axis magnetic sensor into geomagnetic components in the horizontal coordinate system; an azimuth calculating unit for calculating azimuth based on the converted geomagnetic components in the horizontal coordinate system; and a display unit for displaying the calculated azimuth.

Abstract: An attitude detection sensor includes three magnetic sensing parts that detect magnetic field strength in respective directions along three axes perpendicular to each other, and two tilt sensing parts that detect tilt angles around two axes perpendicular to each other. The tilt sensing parts each include a cantilever having a magnet body that moves in accordance with the tilt angle, and a magnetic detection head that detects a displacement of the magnet body. The three magnetic sensing parts and the two magnetic detection heads are each formed using a magnetic detection element of the same type. At least one electronic circuit for controlling the five magnetic detection elements, the three magnetic sensing parts, and the two tilt sensing parts is disposed in a single package in the form of a module.

Abstract: A motion sensor which can easily and accurately detect bearing, attitude and acceleration in any of three-dimensional directions and a portable telephone using the same. The motion sensor comprises three magnetic sensing parts for detecting magnetic field strength in 3-axis directions orthogonal to one another, and three acceleration sensing parts for detecting accelerations in the 3-axis directions. Each of the acceleration sensing parts has a magnet body constituted to be able to displace depending on acceleration, and a magnet displacement detection head for detecting a displacement of the magnet body. The three magnetic sensing parts and the three magnet displacement detection heads are all made of the same type of magnetic detection elements which operate based on common operation principles. The three magnetic sensing parts and the three acceleration sensing parts are integrated into one modular package together with one electronic circuit for controlling these six magnetic detection elements.

Abstract: A dental attachment including a magnet element delivering a magnetic attraction force, a yoke of a soft magnetic material and including a recess for housing the magnet element, and a disc joined to the yoke so as to close the opening of the recess with the magnet element housed in the recess. The yoke has a substantially disc shape portion and collars protruding axially outwardly from the outer peripheral surface of the disc shape portion. The collars are formed to be separated in at least two locations in a substantially peripheral direction, and non-protruding portions having radially outward projection amounts from zero to 50% of the maximum projection amount at the collars are provided between respective collars.

Abstract: A method for manufacturing an anisotropic magnet powder includes a high-temperature hydrogenation process of holding an RFeB-based alloy containing rare earth elements (R), B and Fe as main ingredients in a treating atmosphere under a first treating pressure (P1) of which a hydrogen partial pressure ranges from 10 to 100 kPa and at a first treating temperature (T1) which ranges from 953 to 1133 K, a structure stabilization process of holding the RFeB-based alloy after the high-temperature hydrogenation process under a second treating pressure (P2) of which a hydrogen partial pressure is 10 or more and at a second treating temperature (T2) which ranges from 1033 to 1213 K such that the condition T2>T1 or P2>P1 is satisfied, a controlled evacuation process of holding the RFeB-based alloy after the structure stabilization process in a treating atmosphere under a third treating pressure (P3) of which a hydrogen partial pressure ranges from 0.

Abstract: An electronic compass and direction finding method includes a geomagnetic direction sensor having two sensor elements for detecting perpendicular components of the Earth's magnetic field vector. A microcomputer is coupled to the geomagnetic direction sensor to compute a heading of a vehicle in software. Even if the electronic compass displays directional errors due to magnetization of the vehicle, a center of an azimuth circle can be immediately corrected by a center calculating means and a relatively accurate heading can be displayed. Later, the center of the azimuth circle can be corrected with a higher accuracy by a least squares calculating means. This frees a vehicle driver from uneasiness due to display of an intelligible direction.