JP2007266200A - Magnet composite structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnet composite structure wherein each magnet has high positioning precision. <P>SOLUTION: In this magnet composite structure, a plurality of magnets 3 are arranged and fixed on a substrate 2. The substrate 2 has the reference for positioning the magnets 3 to be arranged. For example, the substrate 2 has two planes bent into L-shape in the cross-section thereof as reference planes 2A and 2B, and the magnets 3 are positioned according to these reference planes 2A and 2B and arranged and fixed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a magnet composite structure incorporated in an application product such as a motor, for example, and relates to a magnet composite structure capable of highly accurate assembly.

  For example, in application products such as various motors, it is indispensable to incorporate a magnet, and until now, the magnet has been assembled alone. In recent years, products using magnets such as motors have been remarkably advanced in precision and characteristics, and magnets with higher characteristics are required. On the other hand, when the magnet is enlarged, heat generation or loss due to eddy current becomes a problem, and countermeasures are desired.

  From such a situation, a mode has been proposed in which a magnet is divided into a plurality of small magnets and these are handled together (see, for example, Patent Document 1 and Patent Document 2). Patent Document 1 discloses a motor magnet in which a required outer peripheral surface of a magnet body composed of a plurality of magnet pieces is fastened and integrated with a high-strength fiber body, and a motor in which the magnet is embedded in a rotor. In the invention described in Patent Document 1, by adopting the above configuration, the divided magnet pieces can be easily integrated, and further, eddy current loss can be reduced.

  Patent Document 2 discloses a permanent magnet for a motor comprising a plurality of divided magnets and an insulating base material and an insulating sheet containing an adhesive, which are arranged on a joint surface of the divided magnets for bonding the divided magnets. In this configuration, the divided magnets are easily bonded to each other to reduce the eddy current generated in the magnets and to ensure insulation between the divided magnets.

  Furthermore, a method has also been proposed in which a magnet piece is fixed to an adhesive sheet or a thin metal plate and then attached to a motor or the like in order to simplify the attachment of the magnet and prevent breakage (for example, Patent Document 3 to Patent Document 3). (See 5).

  Specifically, first, in Patent Document 3, in a method of manufacturing a permanent magnet rotor for an electric motor in which a plurality of permanent magnet pieces are fixedly formed on the outer peripheral surface of a yoke, the required number of permanent magnet pieces is temporarily set on a sheet. A method of manufacturing a permanent magnet rotor is disclosed in which a permanent magnet piece is wound around the outer peripheral surface of a yoke and the permanent magnet piece is disposed at a desired fixing position.

  Patent Document 4 discloses a step of obtaining a band-like body in which permanent magnet pieces having a rectangular bottom surface are arranged in a row in the longitudinal direction of a thin metal plate on a rectangular metal plate, and a permanent magnet piece having an outer peripheral surface. A step of producing a regular polygonal columnar magnet holding portion having the same number of surfaces as the number of arrangements and having a planar shape in which each surface constituting the outer peripheral surface is substantially equal to the bottom surface of the permanent magnet piece; Bending at a portion between adjacent permanent magnet pieces, positioning the permanent magnet pieces on each surface, winding the strip around the outer peripheral surface of the magnet holding portion, and prior to the step of winding the strip around the magnet holding portion A step of magnetizing the piece, a step of mounting a cylindrical spacer so as to enclose the permanent magnet piece wound around the outer peripheral surface of the magnet holding portion, and a step of filling a magnetic binder between the permanent magnet piece and the spacer A manufacturing method of a cylindrical permanent magnet rotor with It is.

Patent Document 5 discloses a permanent magnet fixing method in which a permanent magnet is fixed to a slit hole via an adhesive sheet between the slit hole and the permanent magnet when the permanent magnet is inserted into the slit hole provided in the rotor core. This prevents the magnet from cracking or chipping when the permanent magnet is inserted into the rotor core.
JP 2001-86671 A Japanese Patent Laid-Open No. 2003-164083 JP-A-5-191938 JP 2002-272066 A JP-A-9-163649

  However, when handling a plurality of magnets collectively, the dimensional accuracy of each magnet has not been considered so far. When handling multiple magnets at the same time, there is a risk that the position of each magnet will be slightly shifted, which may cause a shift between the actual magnetic field distribution and the designed magnetic field distribution, which may cause cogging and other operational irregularities. is there.

  The conventional techniques as described in each of the above patent documents can improve the ease of handling and prevent the occurrence of cracks, chips, etc. Can not do it.

  The present invention has been proposed in view of the above-described conventional situation, can be easily assembled, can increase the positioning accuracy of each magnet, and can achieve high accuracy. An object of the present invention is to provide a magnet composite structure. Another object of the present invention is to provide a magnet composite structure having excellent characteristics in terms of strength, for example, a structure in which a magnetized magnet is difficult to fall off.

  In order to achieve the above-mentioned object, the magnet composite structure of the present invention is characterized in that a plurality of magnets are arranged and fixed on a base, and the base has a reference for positioning the arranged magnets. For example, the base has two or more reference surfaces as the reference, and the magnets are arranged by being positioned by these reference surfaces.

  In addition to the above structure, the present invention is characterized in that the base body has, as the reference plane, two planes bent in an L-shaped cross section. Furthermore, the dimension of the reference surface is 50% or more of the corresponding magnet dimension, and is not more than a value obtained by adding 0.5 mm to the magnet dimension. Furthermore, the thickness of the substrate is 0.05 mm to 1.0 mm. Furthermore, the magnet is bonded and fixed to at least one surface of the base. Furthermore, the base is formed of a nonmagnetic material.

  In the magnet composite structure of the present invention, first, since a plurality of magnets are handled in a state of being fixed to the base, the handling is simple. For example, when it is inserted into a rotor slot of a motor, it can be handled and assembled like a single magnet.

  Moreover, in the magnet composite structure of this invention, each magnet is fixed in the state positioned with respect to the base. For example, when the base has two reference surfaces, the two surfaces of the magnet are abutted against these reference surfaces. As a result, the position of each magnet is uniquely determined, and the positioning accuracy is maintained with high accuracy. Therefore, for example, the designed magnetic field distribution and the actual magnetic field distribution agree well.

  Furthermore, in the magnet composite structure of the present invention, each magnet is fixed to the base, which is advantageous in terms of strength. When the magnets are handled together, the joint surfaces are only bonded together in the conventional structure. For example, if the magnets are only bonded between the magnets, for example, if each magnet is magnetized in parallel with the bonding surface, the magnets are likely to fall off during magnetizing or assembling, resulting in an improvement in strength. In the magnet composite structure of the present invention, since each magnet is fixed to the base body, the strength is sufficiently secured, and even when magnetized, the magnet composite structure has a structure that does not easily fall off.

  According to the magnet composite structure of the present invention, the assembly can be easily performed, and the positioning accuracy of each magnet can be increased, and high accuracy can be realized. Moreover, according to the magnet composite structure of the present invention, it is possible to sufficiently secure the fixing strength of each magnet. For example, a magnetized magnet can be made difficult to fall off.

  Hereinafter, specific embodiments of a magnet composite structure to which the present invention is applied will be described in detail with reference to the drawings.

  FIG. 1A shows an example of a magnet composite structure to which the present invention is applied, and FIG. 1B shows a base 2 used for this. The magnet composite structure 1 is formed by fixing a plurality of rectangular parallelepiped magnets 3 to a base body 2 bent in an L shape. That is, the magnet composite structure 1 of the present embodiment uses the two planes 2A and 2B of the base body 2 bent in an L shape as reference planes, and positions and fixes the two planes of each magnet 3 with these reference planes. It has a structure in which magnets 3 are arranged in a line.

  The base 2 is preferably formed of a nonmagnetic material, and preferably has an insulating property. Further, since the base 2 serves as a positioning reference with respect to the magnet 3, it needs to have a certain degree of rigidity. If the base 2 is flexible, it may not be able to play a role in positioning. From such a viewpoint, for example, a metal plate such as stainless steel or a plastic plate can be used. In particular, when importance is attached to the strength of the magnet composite structure 1, it is preferable to use a metal plate such as stainless steel. On the other hand, when importance is attached to insulation and weight reduction, a plastic plate is preferable. Plastic plates are easy to obtain, highly insulating, non-magnetic and lightweight. Note that the metal plate such as stainless steel and the plastic plate are both characterized in that even if scratches are generated due to rubbing, the metal plate is a material that does not easily fall off, and when the magnet composite structure 1 is inserted and attached, The falling powder does not become a problem.

  Moreover, it is preferable to set the thickness of the base 2 appropriately. The magnet composite structure 1 is inserted into a rotor slot of a motor, for example, with a base 2 attached to a magnet 3. Therefore, if the thickness of the base 2 is too thick, the occupied volume of the magnet 3 is reduced, and the surface magnetic flux may be reduced. On the other hand, if the substrate 2 is too thin, it is difficult to ensure the strength, and it will not serve as a reference for the magnet 3, and the substrate 2 may be easily deformed or damaged. There is a fear. Therefore, from these viewpoints, the thickness of the base 2 is preferably 0.05 mm to 1.0 mm. More preferably, it is 0.1 mm-0.2 mm.

  Any magnet can be used as the magnet 3, and the type thereof is not limited. For example, a rare earth sintered magnet is preferable from the viewpoint of improving the magnetic characteristics of the magnet composite structure 1. The rare earth sintered magnet has, for example, a rare earth element R, a transition metal element T, and boron as main components, and the magnet composition is not particularly limited, and may be arbitrarily selected according to the application. For example, the rare earth element R specifically means Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb or Lu. 1 type (s) or 2 or more types can be used. Among these, it is preferable that the main component as the rare earth element R is Nd because it is abundant in resources and relatively inexpensive. As the transition metal element T, any of the conventionally used transition metal elements can be used. For example, one or more of Fe, Co, Ni and the like can be used. Among these, from the viewpoint of magnetic properties, Fe is the main component, and it is particularly preferable to add Co that is effective in improving the Curie temperature and improving the corrosion resistance of the grain boundary phase. In addition to the rare earth element R, transition metal element T, and boron B, the inclusion of other elements is allowed. For example, elements such as Al, Cu, Zr, Ti, Bi, Sn, Ga, Nb, Ta, Si, V, Ag, and Ge can be appropriately contained.

  As shown in FIG. 2A, the magnet 3 is positioned in the left-right direction in the figure by abutting one end surface 3a against the vertical reference surface 2A of the base 2, and the bottom 3b is set as a horizontal reference of the base 2 Positioning in the vertical direction in the figure is performed by supporting the surface 2B. At this time, it is preferable that the dimension of each reference surface 2A, 2B is 50% or more of the dimension of the corresponding magnet 3 and not more than a value obtained by adding 0.5 mm to the dimension of the magnet 3.

  For example, as shown in FIG. 2B, when the dimension (thickness dimension) of the end surface 3a of the magnet 3 is T1, and the height of the reference surface 2A against which the end surface 3a is abutted is T2, T2 ≧ 0. 5 × T1 is preferable. More preferably, T2 ≧ 0.8 × T1. As shown in FIG. 2C, when T2> T1, it is preferable to satisfy T2−T1 ≦ 0.5 mm, and it is more preferable to satisfy T2−T1 ≦ 0.2 mm. Similarly, with respect to the length dimension L1 of the magnet 3, as shown in FIG. 2B, when the dimension of the reference surface 2B on which the bottom surface 3b is supported is L2, L2 ≧ 0.5 × L1. It is preferable. More preferably, L2 ≧ 0.8 × L1. As shown in FIG. 2C, when L2> L1, L2−L1 ≦ 0.5 mm is preferable, and L2−L1 ≦ 0.2 mm is more preferable.

  If the dimension of each reference surface 2A, 2B is less than 50% of the dimension of the corresponding magnet 3, there is a risk that the dimensional accuracy will deteriorate. In view of strength, it is preferably 80% or more of the dimension of the magnet 3. Furthermore, it is preferable that the dimensions of the reference surfaces 2A and 2B are the same as or slightly larger than the dimensions of the corresponding magnet 3. If the dimension of the reference surfaces 2A, 2B protruding from the magnet 3 (T2-T1 or L2-L1) exceeds 0.5 mm, there is a risk of obstructing the assembly. The occupied volume of the magnet 3 becomes small, which may be disadvantageous in terms of magnetic characteristics. By making the dimensions 0 mm or more and 0.5 mm or less, it is effective in preventing cracks and chipping when the magnet composite structure 1 is mounted, and does not interfere with the assembly, and can cope with the dimensional tolerance of the magnet 3. Become. Considering magnetic characteristics, it is preferably 0 mm or more and 0.2 mm or less.

  The magnets 3 are preferably fixed to the base body 2 by adhesion or the like. In this case, at least the bottom surface 3b and the reference surface 2B of the magnet 3 or any one of the end surface 3a and the reference surface 2A may be bonded and fixed. Preferably, in addition to the bottom surface 3b, the end surface 3a and the reference surface 2A are also bonded, and the surfaces of the magnets 3 that are in contact with each other are also bonded. Thereby, an extremely strong adhesive fixing state can be realized.

  The magnets 3 and the base 2 may be fixed or the magnets 3 may be fixed using an adhesive such as an epoxy resin, or may be attached using a double-sided pressure-sensitive adhesive sheet. The adhesive has the advantage that it can be firmly fixed, and the adhesive sheet has the advantage that it can be simply fixed.

  In the magnet composite structure 1 according to the present embodiment, as described above, each magnet 3 is firmly fixed by adhesion to the base 2 or the like, and therefore, as shown in FIG. 4 may be interposed. By interposing the insulating layer 4, eddy current loss can be reduced. As the insulating layer 4, a sheet-like material such as a resin film or paper can be used, and a material previously formed in a sheet shape may be sandwiched. Or you may form in the joint surface of the magnet 3 by methods, such as application | coating. In the case of a magnet structure in which a plurality of magnets are integrated only by adhesion between the magnets 3, it is difficult to ensure strength when the insulating layer 4 is interposed. On the other hand, in the magnet composite structure 1 of the present embodiment, the strength is ensured by bonding and fixing the magnet 3 and the base 2, so that the strength reduction becomes a problem by interposing the insulating layer 4. Never become. When further improvement in strength is required, the insulating layer 4 is preferably an adhesive sheet, an adhesive sheet, or an adhesive layer having adhesiveness.

  In the magnet composite structure 1 having the above-described configuration, each magnet 3 can be positioned with high accuracy, and the dimensional accuracy of the entire magnet composite structure 1 can be increased. Therefore, for example, when incorporated in a motor or the like, variations in the gap between the rotor and the stator can be reduced, and as a result, the gap can be designed to be small, contributing to miniaturization and high performance. In addition, since the magnet 3 is fixed not only between the magnets 3 but also between the magnet 3 and the base 2 by adhesion or the like, the strength of the magnet composite structure 1 can be increased, and the magnet 3 is magnetized. In some cases, the structure can be made difficult to drop off. Furthermore, since a plurality of magnets 3 can be handled collectively in a state of being fixed to the base 2, the assembly can be easily performed, and the magnet 3 is protected by the base 2 during the insertion assembly, It is possible to prevent the magnet 3 from cracking or chipping. Without the base 2, the edges and corners of the magnet 3 are exposed, and cracks and chips are likely to occur. For example, in a motor or the like, if a fallen object generated by cracking or chipping of the magnet 3 enters between the rotor and the stator, the rotation may be locked to cause a serious failure. On the other hand, if the magnet composite structure 1 of this embodiment is used, the occurrence of the cracks and chips can be suppressed, and the failure can be reliably avoided.

  Actually, a magnet composite structure as shown in FIG. 1 was produced by using a magnet of 4 mm × 19.5 mm × 5 mm and stacking it on an L-shaped base (L-shaped base). At this time, the dimension of the L-shaped substrate was 32.55 mm × 19.7 mm × 5.25 mm, and the wall thickness was 0.15 mm. The size of the eight stacked magnet bodies is 32.35 mm × 19.5 mm × 5 mm, and the dimension of the L-shaped substrate is about 0.2 mm larger. Each magnet and the reference surface 2B of the L-shaped base were bonded with an epoxy resin, and each magnet was also bonded with an epoxy resin. The magnetizing direction of each magnet was perpendicular to the reference plane 2B. As a result, a magnet composite structure having excellent dimensional accuracy and extremely high strength could be produced. Further, when the produced magnet composite structure was inserted into the rotor slot of the motor, it could be inserted smoothly as if handling one magnet, and there was no occurrence of cracks or chipping.

  As mentioned above, although embodiment of the magnet composite structure to which this invention is applied has been described, this invention is not limited to this embodiment, and various changes are possible. Hereinafter, modifications of the magnet composite structure 1 will be described.

  FIG. 4A shows an example of the base 2 provided with three orthogonal reference surfaces 2A, 2B, and 2C. As shown in FIG. 4B, the reference surface 2A supports the end surface 3a of the magnet 3, and the reference surface 2B supports the bottom surface 3b of the magnet 3. In this example, the reference surface 2C is positioned at the end. The side surface of the magnet 3 is supported. In this way, by arranging three orthogonal planes as reference planes, the arranged magnets 3 are completely fixed in spatial coordinates, and no positional deviation occurs in any direction. Further, by inserting and assembling from the reference surface 2C, it is possible to further prevent the magnet from being cracked or chipped.

  FIG. 5A shows an example in which the shape of the magnet 3 is, for example, an umbilical shape when the upper surface includes a curved surface. In the magnet 3, the surfaces that are in contact with the reference surfaces 2 </ b> A and 2 </ b> B of the base 2 are not necessarily flat. As shown in FIG. 5 (b), the magnet-shaped magnet 3 also has the same shape as the rectangular parallelepiped-shaped magnet 3 as long as the arc-shaped side faces the reference surface 2A while the bottom surface 3b is supported by the reference surface 2B. It is possible to fix the positioning.

  FIG. 6A shows an example in which the reference surface 2B of the base 2 is an arc surface corresponding to the arc-shaped magnet 3. The reference surface against which the magnet 3 is abutted does not necessarily have to be a flat surface. If the reference surface 2B is an arc surface having the same radius of curvature as the inner arc surface of the arc-shaped magnet 3, it also functions as a reference surface. Therefore, as shown in FIG. 6B, if the arc-shaped bottom surface 3b of the arc-shaped magnet 3 is supported by the arc-shaped reference surface 2B and the end edge 3a is abutted against the reference surface 2A, the previous embodiment. It can be positioned and fixed in the same manner as described above.

  FIG. 7 shows an example in which a skew is provided. As shown in FIG. 7A, the base body 2 has a step structure, and the reference surface 2A is installed in a step shape, so that the arranged magnets 3 have a step as shown in FIG. 7B. And a skew structure. In this case, each of the step-like reference surfaces 2A serves as a reference for positioning the magnet 3, so that the magnet 3 can be accurately stepped. As a result, the magnet composite structure 1 skewed with high accuracy and good reproducibility can be manufactured. In the base 2, the stepped reference surface 2A may be formed by changing a mold for molding the base 2, or may be formed by combining strip-shaped members with steps.

  Furthermore, although illustration is omitted, for example, a structure in which two L-shaped bases 2 are combined and the magnet 3 is wrapped may be employed. In this case, the magnet 3 is positioned by using the reference surfaces 2A and 2B of the one base 2, and the other base 2 is used as a simple protective surface.

(A) is a schematic perspective view which shows an example of a magnet composite structure, (b) is a schematic perspective view which shows an example of a base | substrate. (A) is a figure which shows the positional relationship of a base | substrate and a magnet, (b) And (c) is a figure which shows the dimensional relationship of a reference plane and a magnet. It is a disassembled perspective view which shows the example which interposed the insulating sheet between the magnets. (A) is a schematic perspective view of an example of a base body using three orthogonal planes as a reference plane, and (b) shows a magnet positioning state based thereon. (A) is a disassembled perspective view which shows the magnet composite structure at the time of making a magnet shape into a kamaboko shape, (b) is a figure which shows the abutting state to the base | substrate of the magnet which has a kamaboko shape. (A) is a disassembled perspective view which shows the magnet composite structure when a magnet shape is made into an arc shape, (b) is a figure which shows the abutting state to the base | substrate of the magnet which has an arc shape. (A) is a schematic plan view which shows the attachment state of the magnet to the base | substrate which has a stair-like reference surface, (b) is a schematic plan view of the magnet composite structure with a skew.

Explanation of symbols

1 Magnet composite structure, 2 base, 2A, 2B, 2C reference surface, 3 magnet, 3a end surface, 3b bottom surface, 4 insulating layer

Claims (7)

  A magnet composite structure comprising a plurality of magnets arranged and fixed on a base, the base having a reference for positioning the magnets to be arranged.   The magnet composite structure according to claim 1, wherein the base body has two or more reference surfaces, and the magnets are arranged by being positioned by the reference surfaces.   The magnet composite structure according to claim 2, wherein the base has two planes bent in an L-shaped cross section as the reference plane.   4. The magnet composite structure according to claim 2, wherein a dimension of the reference surface is 50% or more of a corresponding magnet dimension and is equal to or less than a value obtained by adding 0.5 mm to the magnet dimension. 5.   5. The magnet composite structure according to claim 1, wherein the base has a thickness of 0.05 mm to 1.0 mm.   6. The magnet composite structure according to claim 1, wherein the magnet is bonded and fixed to at least one surface of the base. The magnet composite structure according to claim 1, wherein the base is made of a nonmagnetic material.

Images