109results about How to "Avoid magnetization" patented technology

In the thin-film magnetic head of the present invention, the length of each of a pinned layer and an antiferromagnetic layer in their contact area in the depth direction from a surface facing a medium is longer than the length of a free layer in the same direction. When the length of the pinned layer in the depth direction is set longer as such, the direction of magnetization of the pinned layer can be restrained from being tilted by disturbances. Also, the pinned layer and the antiferromagnetic layer have the same length in their contact area in the MR height direction, so that the pinned layer is in contact with the antiferromagnetic layer throughout its length in the MR height direction, thus raising the exchange coupling force, whereby the inclination in the direction of magnetization can be suppressed more effectively.

There are provided a permanent magnet and a manufacturing method thereof capable of inhibiting grain growth of magnet grains having single domain particle size during sintering so as to improve magnetic properties. To fine powder of milled neodymium magnet is added an organometallic compound solution containing an organometallic compound expressed with a structural formula of M-(OR)_x (M represents V, Mo, Zr, Ta, Ti, W or Nb, R represents a substituent group consisting of a straight-chain or branched-chain hydrocarbon, _x represents an arbitrary integer) so as to uniformly adhere the organometallic compound to particle surfaces of the neodymium magnet powder. Thereafter, the desiccated magnet powder is calcined by utilizing plasma heating and the powdery calcined body is sintered so as to form a permanent magnet 1.

The invention discloses a segmented rotor consequent pole permanent magnet motor. The segmented rotor consequent pole permanent magnet motor comprises two segments of rotors, wherein the two segments of rotors are connected in an axial direction of the rotors, a surface of each segment of rotor is provided with multiple convex poles, grooves among the adjacent convex poles are embedded with permanent magnets, a convex pole and permanent magnet alternating arrangement structure is formed on surfaces of the rotors, the shape of the permanent magnets is in matching with the shape of the grooves, each surface of the permanent magnets and each surface of the grooves realize tight contact, upper surfaces of the permanent magnets and upper surfaces of the convex poles are arc-shaped surfaces, radian of the upper surfaces of the permanent magnets and radian of the upper surfaces of the convex poles are identical, all the upper surfaces of the convex poles and all the upper surfaces of the permanent magnets form an integral cylindrical surface, the permanent magnets on the two segments of rotors circumferentially offset for a half electric period angle, magnetizing directions of the permanent magnets on one segment of rotor are identical, and magnetizing directions of the permanent magnets on different segments of rotors are opposite. The segmented rotor consequent pole permanent magnet motor is advantaged in that disadvantages of a traditional surface-mounted permanent magnet motor are solved, permanent magnet materials and protection sleeves are saved, and magnetization of an end portion of a rotation shaft can be avoided.

The invention discloses a biological endogenous magnetic particle detection device. A gradient receiving coil (6) is connected with an input coil of a low-temperature DC superconducting quantum interference device (2); the low-temperature DC superconducting quantum interference device (2) is connected with a preamplifier (4); and the low-temperature DC superconducting quantum interference device (2), the gradient receiving coil (6) and a low-temperature data wire (5) are packaged in a low-temperature non-magnetic Dewar (1). When DC passes through a magnetization and demagnetization unit (3), a static magnetic field is generated to magnetize a biological sample; and when AC passes through the magnetization and demagnetization unit (3), an AC magnetic field is generated to demagnetize the biological sample. A mobile platform and a magnetization and demagnetization unit controller (10) complete control signal acquisition and feedback control of the magnetization and demagnetization unit (3) and the mobile platform (8). The low-temperature non-magnetic Dewar (1), the magnetization and demagnetization unit (3), the magnetic nanoparticle-containing biological sample (7), the mobile platform (8) and a non-magnetic sample holder (9) are arranged in a magnetically shielded room (13).

the present invention aims to achieve that geomagnetism can be sensed in high precision while eliminating an adverse influence by magnetic noise with respect to a geomagnetic sensor provided in a housing, and correct azimuth information can be acquired.

A portable terminal apparatus according to the present invention is arranged by that both a first housing (11) and a second housing (12) are coupled to each other by way of a hinge portion (13) under pivotable condition, a geomagnetic sensor (33) is provided on a circuit board (32) in the second housing (12), and also, a speaker (19) is provided on the side of a rear surface thereof. Both this geomagnetic sensor (33) and a speaker (19) corresponding to a component for generating magnetic noise which gives an adverse influence with respect to the geomagnetic sensor (33) are provided in the vicinity of each other within the same second housing (12), and both the members are arranged on the same plane. In this structure, since a magnetic force line (35) which is caused by magnetic noise generated from a magnet (19a) of the speaker (19) is intersected with respect to the geomagnetic sensor (33) at a right angle, and thus, a horizontal direction component thereof is not produced, the geomagnetic sensor (33) can correctly sense the geomagnetism without being adversely influenced by the magnetic noise.

There are provided a permanent magnet and a manufacturing method thereof that enables concentration of V, Mo, Zr, Ta, Ti, W or Nb contained in an organometallic compound in grain boundaries of the permanent magnet. To fine powder of milled neodymium magnet is added an organometallic compound solution containing an organometallic compound expressed with a structural formula of M-(OR)_x (M represents V, Mo, Zr, Ta, Ti, W or Nb, R represents a substituent group consisting of a straight-chain or branched-chain hydrocarbon, _x represents an arbitrary integer) so as to uniformly adhere the organometallic compound to particle surfaces of the neodymium magnet powder. Thereafter, a compact body obtained by compacting the magnet powder is held for several hours in hydrogen atmosphere at 200 through 900 degrees Celsius so as to perform a calcination process in hydrogen. Thereafter, through sintering, a permanent magnet is manufactured.

There are provided a permanent magnet and a manufacturing method thereof capable of decreasing an activity level of a calcined body activated by a calcination process. To fine powder of milled neodymium magnet is added an organometallic compound solution containing an organometallic compound expressed with a structural formula of M-(OR)_x (M represents V, Mo, Zr, Ta, Ti, W or Nb, R represents a substituent group consisting of a straight-chain or branched-chain hydrocarbon, _x represents an arbitrary integer) so as to uniformly adhere the organometallic compound to particle surfaces of the neodymium magnet powder. Thereafter, desiccated magnet powder is held for several hours in hydrogen atmosphere at 200 through 900 degrees Celsius. Thereafter, the powdery calcined body calcined through the calcination process in hydrogen is held for several hours in vacuum atmosphere at 200 through 600 degrees Celsius for a dehydrogenation process.

There are provided a permanent magnet and a manufacturing method thereof enabling carbon content contained in magnet particles to be reduced in advance before sintering even when wet milling is employed. Coarsely-milled magnet powder is further milled by a bead mill in a solvent together with an organometallic compound expressed with a structural formula of M-(OR)_X (M represents V, Mo, Zr, Ta Ti W or Nb, R represents a substituent group consisting of a straight-chain or branched-chain hydrocarbon, X represents an arbitrary integer) so as to uniformly adhere the organometallic compound to particle surfaces of the magnet powder. Thereafter, a compact body of compacted magnet powder is held for several hours in hydrogen atmosphere at 200 through 900 degrees Celsius to perform hydrogen calcination process. Thereafter, through sintering process, a permanent magnet 1 is formed.

The invention discloses a magnetic field enhanced consequent-pole permanent magnet motor, comprising n rotor sections, wherein the n rotor sections are connected in sequence in the axial direction of a rotor, an annular permanent magnet magnetized axially is arranged between two adjacent rotor sections, and the magnetized directions of the adjacent annular permanent magnets are opposite; the n rotor sections are of the same structure, a plurality of salient poles are uniformly arranged on the surface of each rotor section, a permanent magnet is embedded into a groove between the adjacent salient poles, and an alternate arrangement structure of the salient poles and the permanent magnets is formed on the surface of the rotor; the magnetized directions of the permanent magnets on the surface of the same rotor section are same, and the magnetized directions of the permanent magnets on the surfaces of the adjacent rotor sections are opposite; a hollow cylindrical permanent magnet is arranged between the inner side of each rotor section and a rotating shaft, and the magnetized directions of the permanent magnets on the inner sides of the two adjacent rotor sections are opposite. The magnetic field enhanced consequent-pole permanent magnet motor overcomes the defects of a traditional surface-mounted permanent magnet motor, reduces the cost of a permanent magnet material, and enhances the output torque.

There are provided a permanent magnet and a manufacturing method thereof capable of densely sintering the entirety of the magnet without making a gap between a main phase and a grain boundary phase in the sintered magnet. To fine powder of milled neodymium magnet is added an organometallic compound solution containing an organometallic compound expressed with a structural formula of M-(OR)_x (M represents V, Mo, Zr, Ta, Ti, W or Nb, R represents a substituent group consisting of a straight-chain or branched-chain hydrocarbon, x represents an arbitrary integer) so as to uniformly adhere the organometallic compound to particle surfaces of the neodymium magnet powder. Thereafter, desiccated magnet powder is held for several hours in hydrogen atmosphere at 200 through 900 degrees Celsius. Thereafter, the powdery calcined body calcined through the calcination process in hydrogen is held for several hours in vacuum atmosphere at 200 through 600 degrees Celsius for a dehydrogenation process.