Abstract: The permanent magnet member 10 for a voice coil motor (VCM) in accordance with the present invention comprises a magnet body 1 including a shorter periphery 11, a longer periphery 12 located at a position separated from the shorter periphery 11 by a predetermined distance, and a pair of side peripheries 13, 14 connecting the shorter periphery 11 and longer periphery 12 to each other, the magnet body having a fan-shaped planar form; and a corrosion-resistant film (Ni plating film 2) applied to a surface of the magnet body. The permanent magnet member 10 has a thickness whose maximum and minimum values yield a difference of 10 to 150 ?m therebetween.

Abstract: A rare-earth magnet having a protective film for enhancing a corrosion resistance is provided. The protective film is a three-layer film including a first protective layer with a crystalline structure ? (for example, a polycrystalline structure), a second protective layer with a crystalline structure ? (for example, a columnar-crystalline structure), and a third protective layer with the crystalline structure ? from the side near a magnet body. Since the adjoining first and second protective layers have different crystalline structures from each other, and the adjoining second and third protective layers have also different crystalline structures from each other, compactness among the three layers in the protective film may be improved. Therefore, development of a pinhole is restrained, and corrosion of the protective film can be restrained.

Abstract: The permanent magnet member 10 for a voice coil motor (VCM) in accordance with the present invention comprises a magnet body 1 including a shorter periphery 11, a longer periphery 12 located at a position separated from the shorter periphery 11 by a predetermined distance, and a pair of side peripheries 13, 14 connecting the shorter periphery 11 and longer periphery 12 to each other, the magnet body having a fan-shaped planar form; and a corrosion-resistant film (Ni plating film 2) applied to a surface of the magnet body. The permanent magnet member 10 has a thickness whose maximum and minimum values yield a difference of 10 to 150 ?m therebetween.

Abstract: A magnet body 1 including a shorter periphery 11, a longer periphery 12 located at a position separated from the shorter periphery 11 by a predetermined distance, and a pair of side peripheries 13, 14 connecting the shorter periphery 11 and longer periphery 12 to each other, the magnet body having a fan-shaped planar form; and a corrosion-resistant film (Ni plating film 2) applied to a surface of the magnet body. The permanent magnet member 10 has a thickness whose maximum and minimum values yield a difference of 10 to 150 ?m therebetween.

Abstract: A rare earth magnet having excellent corrosion resistance is provided. It has a magnet body (10) containing a rare earth element, and a protective film (20) formed on the magnet body (10). In the protective film (20), a first protective film (21), a second protective film (22) and a third protective film (23) are laminated in this order from the side of the magnet body (10). These are in a polycrystalline state and composed of a metal plated film, for example. The first protective film (21) and the third protective film (23) have a smaller mean crystal grain size than that of the second protective film (22). Microcrystallization of the first protective film (21) can improve the density of the interface between the protective film (20) and the magnet body (10), and decrease the number of pinholes.

Abstract: Provided are a method of manufacturing a rare-earth magnet with superior corrosion resistance, and a plating bath used for the method. A first protective film including nickel and a second protective film including nickel and sulfur are laminated in order on a magnet body including a rare-earth element. The first protective film is formed through electroplating with a first plating bath including a nickel source, a conductive salt and a pH stabilizer, and having a concentration of the nickel source of 0.3 mol/l to 0.7 mol/l on a nickel atom basis and a conductivity of 80 mS/cm or over. Thereby, a rare-earth-rich phase can be prevented from being leached out, and the production of pinholes can be reduced. Therefore, the corrosion resistance of the rare-earth magnet can be improved.

Abstract: An R-T-B system permanent magnet 1 comprises a magnet body 2 comprising a sintered body comprising at least a main phase comprising R2T14B grains (wherein R represents one or more rare earth elements, and T represents one or more transition metal elements including Fe or Fe and Co essentially) and a grain boundary phase containing R in a larger amount than the main phase, the magnet body 2 having a 300 ?m or less thick (not inclusive of zero thick) hydrogen-rich layer 21 having a hydrogen concentration of 300 ppm or more formed in the surface layer portion, and an overcoat 3 covering the surface of the magnet body 2 can improve the corrosion resistance of the R-T-B system permanent magnet 1 with an overcoat 3 formed thereon without degrading the magnetic properties thereof.

Abstract: A rare earth magnet having excellent corrosion resistance is provided. It has a magnet body (10) containing a rare earth element, and a protective film (20) formed on the magnet body (10). In the protective film (20), a first protective film (21), a second protective film (22) and a third protective film (23) are laminated in this order from the side of the magnet body (10). These are in a polycrystalline state and composed of a metal plated film, for example. The first protective film (21) and the third protective film (23) have a smaller mean crystal grain size than that of the second protective film (22). Microcrystallization of the first protective film (21) can improve the density of the interface between the protective film (20) and the magnet body (10), and decrease the number of pinholes.

Abstract: An R-T-B system permanent magnet 1 comprises a magnet body 2 comprising a sintered body comprising at least a main phase comprising R2T14B grains (wherein R represents one or more rare earth elements, and T represents one or more transition metal elements including Fe or Fe and Co essentially) and a grain boundary phase containing R in a larger amount than the main phase, the magnet body 2 having a 300 ?m or less thick (not inclusive of zero thick) hydrogen-rich layer 21 having a hydrogen concentration of 300 ppm or more formed in the surface layer portion, and an overcoat 3 covering the surface of the magnet body 2 can improve the corrosion resistance of the R-T-B system permanent magnet 1 with an overcoat 3 formed thereon without degrading the magnetic properties thereof.

Abstract: The present invention provides a rare-earth magnet capable of enhancing a corrosion resistance. A protective film is a three-layer film including a first protective layer with a crystalline structure ? (for example, a polycrystalline structure), a second protective layer with a crystalline structure ? (for example, a columnar-crystalline structure), and a third protective layer with the crystalline structure ? from the side near a magnet body. Since the adjoining first and second protective layers have different crystalline structures from each other, and the adjoining second and third protective layers have also different crystalline structures from each other, compactness among the three layers in the protective film may be improved. Therefore, development of a pinhole is restrained, and corrosion of the protective film can be restrained.

Abstract: The permanent magnet member 10 for a voice coil motor (VCM) in accordance with the present invention comprises a magnet body 1 including a shorter periphery 11, a longer periphery 12 located at a position separated from the shorter periphery 11 by a predetermined distance, and a pair of side peripheries 13, 14 connecting the shorter periphery 11 and longer periphery 12 to each other, the magnet body having a fan-shaped planar form; and a corrosion-resistant film (Ni plating film 2) applied to a surface of the magnet body. The permanent magnet member 10 has a thickness whose maximum and minimum values yield a difference of 10 to 150 ?m therebetween.

Abstract: It is an object of the present invention to provide an R—T—B system permanent magnet which is easy to apply in the production of an actual R—T—B system permanent magnet, and which contains a plating film that is also effective in securing hardness. The present invention achieves this object by providing an R—T—B system permanent magnet 1 which contains a magnet base body 2 constituted from a sintered body which contains at least main phase grains containing an R2T14B compound, and a grain boundary phase which contains a larger amount of R than the main phase grains, and a plating film 3 which covers the magnet base body 2 surface and which contains, when C content is defined as Cc (wt. %), 0.005<Cc?0.2 wt. %.

Abstract: A bending sequence and bending die proposing apparatus for a sheet metal part, includes: means for storing a development drawing of the sheet metal part; means for detecting a plurality of bending sequence candidates capable of manufacturing the sheet metal part, and bending die candidates to be used in the respective bending steps in the respective bending sequence candidates, based on the development drawing; and means for displaying the plurality of bending sequence candidates. The display includes information representing the number of stages in the respective bending sequence candidates.

Abstract: Provided are a method of manufacturing a rare-earth magnet with superior corrosion resistance, and a plating bath used for the method. A first protective film including nickel and a second protective film including nickel and sulfur are laminated in order on a magnet body including a rare-earth element. The first protective film is formed through electroplating with a first plating bath including a nickel source, a conductive salt and a pH stabilizer, and having a concentration of the nickel source of 0.3 mol/l to 0.7 mol/l on a nickel atom basis and a conductivity of 80 mS/cm or over. Thereby, a rare-earth-rich phase can be prevented from being leached out, and the production of pinholes can be reduced. Therefore, the corrosion resistance of the rare-earth magnet can be improved.

Abstract: A bending sequence and bending die proposing apparatus for a sheet metal part, includes: means for storing a development drawing of the sheet metal part; means for detecting a plurality of bending sequence candidates capable of manufacturing the sheet metal part, and bending die candidates to be used in the respective bending steps in the respective bending sequence candidates, based on the development drawing; and means for displaying the plurality of bending sequence candidates. The display includes information representing the number of stages in the respective bending sequence candidates.

Abstract: A sighting apparatus comprising an optical system which includes a laser oscillator and an automatic correction mechanism mounted on a rotational table, wherein the laser beams from the oscillator are emitted in any horizontal direction by remote control. A circular air bubble tube is provide on the table such that the position of an air bubble in the tube is sensed by a photosensor to recognize the tilt of the table. When the tilt of the table exceeds an effective operation range of the automatic correction mechanism, an interrupter circuit is operated to interrupt a power source circuit for the laser oscillator.

Abstract: A sighting apparatus in which a laser oscillator and an optical system are provided on a rotational table and in which the laser beam is emitted in any horizontal direction by remote control. A movement conversion mechanism which converts a rotational movement to a linear movement, and a drive unit which comprises a motor operated by remote control and a reduction gear mechanism which transmits the rotation of the motor to the movement conversion mechanism are provided on the table. The movement conversion mechanism is connected to a movable mirror cylinder which holds a focusing lens constituting a part of the optical system to move the focusing lens by remote control.