JP2018067635A - Pin penetration bonded magnet, magnet structure, and process for producing pin penetration bonded magnet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pin penetration bonded magnet capable of being strongly fixed even in a severe environment without using an adhesive despite of being a segment shape or a ring shape, which is thin and small, a magnet structure using the same, and a method for producing the pin penetration bonded magnet.SOLUTION: A pin penetration bonded magnet 1 includes: an arcuate bonded magnet body 11; and two non-magnetic pins 12, 12 integrally penetrating the bonded magnet body 11 in such a manner that both end portions 12a, 12b protrude from the bonded magnet body 11. The pin penetration bonded magnet 1 is manufactured by a compression molding method.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a pin-through bond magnet, a magnet structure using the pin-through bond magnet, and a manufacturing method for manufacturing the pin-through bond magnet.

  In a rotary motor, an acoustic speaker, and the like provided with a permanent magnet, it is common to use an adhesive to bond and fix the permanent magnet to the casing (Patent Documents 1 and 2). For example, in a rotary motor, a plurality of segment-shaped (bow-shaped or kamaboko-shaped) permanent magnets are fixed to the outer periphery of a stator core with an adhesive. The reason why the adhesive is used in this way is that the permanent magnet is a functional member for generating a magnetic force, and is not a structural member that can be mechanically fastened with a screw, a pressing plate, or the like.

  The adhesive strength of the adhesive depends on various factors such as the adhesive strength of the adhesive itself, the adhesive area, how to spread the adhesive, the distance between the two adherends, the surface roughness of the adhesive surface, and the wettability. Change significantly. Therefore, in consideration of the variation in the adhesive force generated in this way, for example, the adhesion area is assumed to be about 1/3 of the actual total contact area, or the safety factor is set to be three times higher.

  Despite such measures, when the adhesive was not sufficiently cured or the adhesive changed over time, the adhesive was fixed due to the effects of magnetic repulsion, rotational centrifugal force, etc. Permanent magnets may peel off and scatter.

  Therefore, a method for fixing a segment-shaped or ring-shaped permanent magnet without using an adhesive has been proposed (Patent Documents 3 and 4). In Patent Document 3, a permanent magnet holding member made of a synthetic resin fixedly provided on the outer peripheral portion of the rotor body is used, and a permanent magnet is interposed between the claw portions of adjacent rod-like portions extending in the axial direction of the permanent magnet holding member. Is inserted, and both outer edge portions of the permanent magnet are held and fixed by the claw portions of the rod-shaped portion. In Patent Document 4, a disk-shaped yoke material having a shaft hole at the center is attached to both opening ends of a cylindrical body made of a composite magnet, and the shaft is inserted into the shaft hole and assembled integrally.

JP 2004-236366 A JP 2002-58183 A JP 2010-207075 A JP-A-3-124237

  As permanent magnets have increased in magnetic force, their shapes are becoming lighter, thinner and shorter. Therefore, in a thin segment-shaped permanent magnet, it is difficult to hold and fix only with an outer edge portion other than the magnetic pole surface as described in Patent Document 3. This is because when holding and fixing only with the outer edge portion, stress concentration such as bending and twisting occurs in the fixed permanent magnet, and the permanent magnet is damaged. In the configuration of Patent Document 4, since the composite magnet, the yoke material, and the shaft are integrally assembled and fixed, similarly to Patent Document 3, stress concentration such as bending and torsion occurs in the fixed composite magnet, The composite magnet will be damaged.

  The present invention has been made in view of such circumstances, and can be firmly fixed without using an adhesive, even in a harsh environment, despite being a light, thin and small segment shape or ring shape. An object of the present invention is to provide a pin-through bond magnet, a magnet structure using the pin-through bond magnet, and a manufacturing method for manufacturing the pin-through bond magnet.

  A pin-penetrating bond magnet according to the present invention includes a segment-shaped or ring-shaped bond magnet main body, and a plurality of pins integrally penetrating the bond magnet main body in a form in which both end portions protrude from the bond magnet main body. It is characterized by providing.

  In the pin-penetrating bond magnet of the present invention, a plurality of pins are integrally penetrated into a segment-shaped (for example, bow-shaped or kamaboko-shaped) or ring-shaped bonded magnet body, and both ends of the pins are bonded. Projects from the magnet body. The fastening force between the bonded magnet body and the pins is uniformly distributed throughout the magnet without stress concentration on the contact surfaces of each other. Therefore, the bonded magnet main body is not damaged. It is possible to obtain a desired fastening force by adjusting the thickness and the number of pins that penetrate.

  The pin through-type bonded magnet according to the present invention is characterized in that the volume of the pin is 10% or less of the whole.

  In the pin through-type bonded magnet of the present invention, the volume of the pin is 10% or less of the total volume of the magnet. Therefore, it is possible to suppress the deterioration of the magnetic characteristics due to the provision of the pins.

  The pin through-type bonded magnet according to the present invention is characterized in that a depression is formed in the center of the pin.

  In the pin through-type bonded magnet of the present invention, a depression is formed in the central portion in the longitudinal direction of the pin. Therefore, the pin is prevented from coming off from the bonded magnet body.

  The pin through-type bonded magnet according to the present invention is characterized in that the bonded magnet main body includes an R-T-B alloy magnetic powder and a thermosetting resin.

  In the pin through-type bond magnet of the present invention, the bond magnet body is composed of a kneaded product of an R-T-B alloy magnetic powder and a thermosetting resin so as to be suitable for compression molding.

  A magnet structure according to the present invention has one or a plurality of pin-penetrating bond magnets as described above, and a plurality of holes into which one ends of the pins of the one or more pin-penetrating bond magnets are fitted. And a yoke body.

  The magnet structure of the present invention is configured by fitting one end of each pin of a pin-through bond magnet into a corresponding hole in the yoke body. Therefore, the pin through-type bonded magnet is mechanically fastened to the yoke body without using an adhesive.

  The manufacturing method of the pin penetration type bond magnet which concerns on this invention uses a compression molding apparatus which has an upper punch, a lower punch, and a die | dye, makes a segment-shaped or ring-shaped bond magnet main body protrude both ends, and a some pin has it. A method of manufacturing a pin through type bonded magnet for manufacturing a pin through type bonded magnet that penetrates integrally, wherein the upper punch is provided with an upper punch hole through which a pin is inserted, and the lower punch is provided with a pin. A lower punch recess is provided to accommodate one end, a step of preparing a kneaded product of magnetic powder and a thermosetting resin, a step of placing a pin in the lower punch recess, and lowering the lower punch Forming a cavity between the die and the lower punch, filling the formed kneaded material into the formed cavity, raising the pin, and And a step of lowering the upper punch and / or raising the lower punch to compress the kneaded material filled in the cavity. It is characterized by that.

  In the manufacturing method of the pin through-type bond magnet of the present invention, after placing the pin in the lower punch recess, the magnetic powder and the heat are placed in the cavity between the die formed by lowering the lower punch and the lower punch. After filling the kneaded material with the curable resin, raising the pin and inserting a part of the pin into the upper punch hole, the upper punch is lowered and / or the lower punch is raised to compress the kneaded material. Therefore, the pin penetration type bond magnet as described above including the thermosetting resin as the binder can be manufactured with high accuracy.

  According to the present invention, a pin-through type that can be firmly fixed without using an adhesive and does not easily peel off even in a harsh environment despite being a light, thin and small segment shape (bow shape or kamaboko shape) or ring shape. A bonded magnet can be provided.

  Further, according to the present invention, it is possible to provide a magnet structure in which the bonded magnet and the yoke body are firmly fastened without using an adhesive.

  Moreover, according to this invention, the manufacturing method of the pin penetration type | mold bond magnet which can manufacture the above pin penetration type bond magnets can be provided accurately.

It is a perspective view showing composition of a pin penetration type bonded magnet concerning the present invention. It is sectional drawing which shows the structure of the pin penetration type | mold bond magnet which concerns on this invention. It is a perspective view which shows the shape of a pin. It is a figure which shows the process of the manufacturing method of the pin penetration type bond magnet by a compression molding method. It is a figure which shows the process of the manufacturing method of the pin penetration type bond magnet by a compression molding method. It is a figure which shows the manufacturing method of the pin penetration type | mold bond magnet by the injection molding method. It is a perspective view which shows an example of the magnet structure which concerns on this invention. It is an exploded view which shows an example of the magnet structure which concerns on this invention. It is a perspective view which shows the other example of the magnet structure which concerns on this invention. It is an exploded view which shows the other example of the magnet structure which concerns on this invention. It is a perspective view which shows the further another example of the magnet structure which concerns on this invention. It is an exploded view which shows the further another example of the magnet structure which concerns on this invention.

  Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof.

  1 and 2 are a perspective view and a cross-sectional view showing a configuration of a pin through type bonded magnet according to the present invention. The pin-through bond magnet 1 is composed of a bond magnet main body 11 and two pins 12.

  The bonded magnet main body 11 has a light, thin and small bow shape as a whole. For example, the thickness t is 1.5 mm to 5 mm, and the circumferential length L is 30 mm to 50 mm. The length of is about 40 mm. The bond magnet body 11 is configured by curing a kneaded product of magnetic powder and resin (binder). The details of the magnetic powder and resin material used will be described later.

  Two pins 12, 12 are provided integrally with the bonded magnet body 11 at symmetrical positions in the circumferential direction of the bonded magnet body 11 so as to penetrate the bonded magnet body 11 in the longitudinal direction. Both end portions (one end portion 12 a and the other end portion 12 b) of each pin 12 protrude from the bonded magnet main body 11.

  FIG. 3 is a perspective view showing the shape of the pin 12. The pin 12 may be either a magnetic pin or a nonmagnetic pin, but it is preferable to use a nonmagnetic hardened steel, for example, stainless steel SUS420J2. By using hardened steel as the pin 12, the strength of the entire bonded magnet is increased. The pin 12 has a long cylindrical shape (diameter d: 0.5 mm to 2 mm, length L ′: about 50 mm). A depression 12c is formed in the central portion in the longitudinal direction of the pin 12 over the entire region or a partial region in the circumferential direction, and the pin 12 in the pin-penetrating bond magnet 1 is prevented from coming off. The contact surface of the pin 12 with the bonded magnet body 11 may be subjected to processing such as knurling or blasting in order to increase the degree of coupling. Further, the shape of the contact surface of the pin 12 may be a polygonal column such as a square column or an elliptical column.

The magnetic powder used for the bonded magnet body 11 will be described. As the magnetic powder, an RTB-based alloy is used. The R-T-B alloy is an alloy in which the R ₂ T ₁₄ B type compound phase occupies 50% by volume or more as a main phase. R is a rare earth element and contains at least one of Nd (neodymium) and Pr (praseodymium).

The content of R in the R-T-B type alloy is preferably 23% by mass or more and 40% by mass or less, and more preferably 26% by mass or more and 34% by mass or less, in mass%. If the content of R is less than 23% by mass, the coercive force of the RTB-based alloy will decrease. On the other hand, when the content of R exceeds 40% by mass, the ratio of the main phase (R ₂ T ₁₄ B type compound phase) decreases, and the magnetization of the R—T—B system alloy decreases.

  T is an iron group element and corresponds to Fe (iron), Co (cobalt), and Ni (nickel). If Co is added instead of Fe, the Curie point of the RTB-based alloy increases and the magnetic anisotropy of the RTB-based alloy can be obtained more easily, resulting in high magnetization. It is done. In addition, in order to suppress the fall of the magnetization of a R-T-B type alloy, it is preferable that addition of Co is 50 mass% or less of T. Moreover, when a small amount of Ni is added instead of Fe, it becomes easier to obtain the magnetic anisotropy of the RTB-based alloy, and high magnetization can be obtained. In addition, in order to suppress the fall of the magnetization of a R-T-B type alloy, it is preferable that addition of Ni is 5 mass% or less of T.

  Further, the content of T in the R-T-B alloy is preferably 57% by mass or more and 76% by mass or less in mass%. If the T content is less than 57% by mass, the ratio of the main phase is lowered and the magnetization becomes small. On the other hand, when the T content exceeds 76 mass%, a magnetically soft phase is generated in the RTB-based alloy, and the coercive force of the RTB-based alloy is reduced.

  B (boron) may be partially or fully substituted with C (carbon). The B content in the RTB-based alloy is preferably 0.6% by mass or more and 1.6% by mass or less in mass%. If the B content is less than 0.6% by mass, a magnetically soft phase is generated in the RTB-based alloy, and the coercive force of the RTB-based alloy is reduced. On the other hand, when the content of B exceeds 1.6% by mass, the ratio of the main phase decreases, and the magnetization of the RTB-based alloy decreases.

  In addition, other elements may be added to the RTB-based alloy as necessary for improving magnetic anisotropy or coercive force. Examples of additive elements effective for improving magnetic anisotropy include Ga (gallium), Zr (zirconium), and Hf (hafnium). In addition, examples of the additive element effective for improving the coercive force include Cu (copper) and Al (aluminum). In addition, Si (silicon), Ti (titanium), V (vanadium), Cr (chromium), Mn (manganese), Zn (zinc), Ge (germanium), Nb (niobium), In as required. (Indium), Sn (tin), Ta (tantalum), W (tungsten), Pb (lead), or the like may be added to the RTB-based alloy.

  The additive elements can be added alone or in combination of two or more. In the case where the additive element is added for the purpose of the above effect, the addition amount of the additive element in the RTB-based alloy is preferably 7.6 mass% or less (or 5 at% or less). When the addition amount of the additive element to the RTB-based alloy exceeds 7.6% by mass, the ratio of the main phase decreases, and the magnetization of the RTB-based alloy becomes small.

  Next, a resin as a binder (binder) used for the bonded magnet body 11 and solidifying the magnetic powder (R-T-B system alloy) as described above will be described. The kind of resin is suitably selected according to the manufacturing method (compression molding method, injection molding method, extrusion molding method, sheet molding method) of the pin penetration type bonded magnet 1.

  That is, when manufacturing the pin penetration type bond magnet 1 by compression molding, thermosetting resins, such as an epoxy resin, are used. Under the present circumstances, in order to suppress that the coupling | bonding degree of a RTB type alloy and a pin falls, it is preferable that the content rate of the thermosetting resin in the bond magnet main body 11 is 1 mass% or more. Moreover, in order to suppress the fall of the magnetic energy of the pin penetration type bond magnet 1, it is preferable that the content rate of a thermosetting resin is 2.5 mass% or less.

  When manufacturing the pin penetration type bonded magnet 1 by injection molding, a thermoplastic resin such as polyamide resin or polyphenylene sulfide resin (PPS) is used. Moreover, when manufacturing the pin penetration type | mold bond magnet 1 by extrusion molding, thermoplastic resins, such as a polyamide resin or a thermoplastic elastomer, are used. When manufacturing the pin penetration type | mold bond magnet 1 by sheet shaping | molding, thermoplastic resins, such as a thermoplastic elastomer, are used. In addition, in order to suppress the fall of a magnetic characteristic, it is preferable that the content rate of the thermoplastic resin (in the case of injection molding, extrusion molding, and sheet molding) in the bond magnet main body 11 is 50 mass% or less. Moreover, in order to suppress that the coupling | bonding degree of a R-T-B type alloy and a pin falls, it is preferable that the content rate of a thermoplastic resin is 40 mass% or more.

  Hereinafter, a method for manufacturing the pin through-type bonded magnet 1 will be described. First, the example which manufactures the pin penetration type bond magnet 1 with a compression molding method is demonstrated.

  First, the magnetic powder for bond magnets is produced. After melting the RTB-based alloy having a predetermined composition, the RTB-based alloy is thinned by a rapid quenching method (such as jet casting or strip casting). Then, the thin R-T-B alloy is pulverized by a pulverizer so as to have a predetermined particle size. A heat treatment for determining the magnetic properties is performed to obtain a magnetic powder composed of an RTB-based alloy. The obtained magnetic powder and a thermosetting resin (for example, epoxy resin) as a binder (binder) are mixed using a kneader to produce a magnetic powder for a bonded magnet. As for the particle size of the magnetic powder for bonded magnet, the 50% mass particle size obtained from classification with a sieve is preferably 10 μm to 200 μm, and more preferably 50 μm to 150 μm. The magnetic particles for bonded magnets having the above particle sizes can be filled without falling down even if the feeder is pushed into a cavity where a plurality of pins to be described later is disposed. Moreover, the magnetic powder for bonded magnets does not bite between the pin and the recess on the punch surface in the molding process. Furthermore, the pin and the bond magnet can be firmly connected by filling the pin surface (particularly, the depression of the pin) without any gap during press molding.

  Prepare the pin 12. Two pins 12 are obtained by cutting a nonmagnetic wire such as stainless steel into a predetermined size. A recess 12c is formed in the center of each pin 12 by polishing, acid treatment, or the like. In order to increase the degree of coupling between the bonded magnet body 11 and the contact surface of the pin 12, the depth of the recess 12 c is preferably 100 μm to 500 μm. Furthermore, it is preferable to perform processing such as knurling or blasting on the contact surface of the pin 12 in order to increase the degree of coupling. Further, the shape of the contact surface of the pin 12 may be a polygonal column such as a square column or an elliptical column.

  A compression molding apparatus is prepared for use in the compression molding method. 4 and 5 are diagrams showing the steps of the method for manufacturing the pin-penetrating bond magnet 1 by the compression molding method.

  FIG. 4A shows the configuration of the compression molding apparatus, and the compression molding apparatus includes a cylindrical die 21, an upper punch 22, and a lower punch 23. On the molding surface of the upper punch 22, two upper punch holes 22 a extending in an appropriate length in the longitudinal direction are formed. As will be described later, the pin 12 is inserted into the upper punch hole 22a, and the length of the upper punch hole 22a is such that the pin 12 and the upper punch 22 do not interfere during compression molding. A taper 22b is attached to the upper punch hole 22a so that the molding surface side is widened. This taper angle needs to be 3 to 10 degrees with respect to the side surface of the upper punch hole 22a extending to the molding surface of the upper punch 22, but this depends on the mold assembly accuracy of the compression molding apparatus. The proportion of the upper punch hole 22a in the upper punch forming surface is preferably 1% or more and 10% or less. If it exceeds 10%, the presence of the pin 12 increases the strength of the compression-bonded bonded magnet, but the occupancy of the non-magnetic pin 12 increases, which may deteriorate the properties of the bonded magnet.

  On the other hand, two lower punch recesses 23a having a predetermined depth are formed on the molding surface of the lower punch 23, and the end of the pin 12 is accommodated in the lower punch recess 23a as described later. The bottom of the lower punch recess 23a can be raised and lowered independently of the lower punch 23.

  As shown in FIG. 4B, one end of each of the two pins 12 is accommodated in the lower punch recess 23a of the lower punch 23, and the two pins 12 are arranged on the molding surface of the lower punch 23 of the compression molding apparatus. At this time, the position of the pin 12 is adjusted so that the pin 12 can be inserted into the upper punch hole 22a. As shown in FIG. 4C, the lower punch 23 is lowered to form a cavity 24 between the die 21 and the lower punch 23.

  Next, as shown in FIG. 5A, the formed cavity 24 is filled with magnetic powder 25 for bonded magnet that has been prepared, which is a kneaded product of magnetic powder and thermosetting resin. The filling method is not particularly limited, but in order to uniformly fill, the raw material powder is supplied to the feeder body that moves back and forth and has an opening on the lower surface and a raw material supply pipe connected to the upper or rear supply pipe connection opening. After the feeder body moves forward on the die and fills the opening powder formed in the die with the raw material powder, the feeder is a feeder in a powder molding apparatus that retreats (for example, JP-A-9-327798) JP-A-10-118794, JP-A 2010-240697, etc.) are preferably used. After filling, as shown in FIG. 5B, only the pin 12 is raised by an appropriate length. As shown in FIGS. 5C and D, the magnetic powder 25 for bonded magnets is compressed to a predetermined density with the upper punch 22 lowered and the pin 12 inserted through the upper punch hole 22a. Although the upper punch 22 is lowered to compress the bonded magnet magnetic powder 25, the lower punch 23 may be raised to compress the bonded magnet magnetic powder 25, or the upper punch 22 is lowered and lowered. The bond 23 magnetic powder 25 may be compressed by simultaneously raising the punch 23.

  Next, the upper punch 22 and the lower punch 23 are raised while holding the pin-penetrating bond magnet 1 in which the pins 12 are integrated. The pin penetration type bond magnet 1 is put out on the surface of the die 21 and the upper punch 22 is further raised, and then the manufactured pin penetration type bond magnet 1 is taken out. The extracted pin-through bond magnet 1 is subjected to heat treatment. The heat treatment temperature is preferably in the range of 150 ° C. to 400 ° C., and the heat treatment time is preferably 1 minute to 4 hours.

  Next, the example which manufactures the pin penetration type bonded magnet 1 by the injection molding method is demonstrated.

  First, the magnetic powder for bond magnets is produced. After melting the RTB-based alloy having a predetermined composition, the RTB-based alloy is thinned by a rapid quenching method (such as jet casting or strip casting). Then, the thin R-T-B type alloy is pulverized by a pulverizer so as to have a predetermined particle size (preferably about 100 μm). A heat treatment for determining the magnetic properties is performed to obtain a magnetic powder composed of an RTB-based alloy. The obtained magnetic powder and a thermoplastic resin (for example, polyamide resin) as a binder are mixed using a kneader to produce a bond magnet pellet.

  Prepare the pin 12. Two pins 12 are obtained by cutting a nonmagnetic wire such as stainless steel into a predetermined size. A recess 12c is formed in the center of each pin 12 by polishing, acid treatment, or the like.

  An injection molding apparatus is prepared for use in injection molding. FIG. 6 is a diagram showing a method for manufacturing a pin-through bond magnet by an injection molding method. The injection molding apparatus includes a pair of produced split molds 31 and 31 and a gate 32.

  A cavity 33 is formed when one of the split molds 31 is opened and two pins 12 are installed and then the split mold 31 is closed. The produced bonded magnet pellet is melted by heat, and the melted raw material is poured into the cavity 33 through the gate 32. After the flow of the raw material into the cavity 33, the process waits until the raw material cools and solidifies. Further, the split mold 31 is heated or cooled as necessary in order to prevent sink marks or the like of the molded body. After the gate 32 is cut, both the split molds 31 are opened, and the pin penetration type bonded magnet 1 in which the pins 12 are integrated is taken out.

  Hereinafter, a magnet structure using the pin-through bond magnet 1 will be described. 7 and 8 are a perspective view and an exploded view showing an example of a magnet structure according to the present invention.

  In this magnet structure 2, eight pin-penetrating bond magnets 1 having a segment shape as described above are arranged in a circle, and one end 12 a of each pin 12 has an annular yoke material. 41, the other end 12b of each pin 12 is fitted into the corresponding hole 44 of the bottomed cylindrical container 43.

  9 and 10 are a perspective view and an exploded view showing another example of the magnet structure according to the present invention. In this magnet structure 3, eight pin-penetrating bonded magnets 1 having the segment shape as described above are arranged in a circle, and one end 12 a of each pin 12 is formed in an upper annular shape. The yoke member 45 is fitted into the corresponding hole 46, and the other end 12 b of each pin 12 is fitted into the corresponding hole 48 of the lower annular yoke material 47. In this example, only one stage of the annular arrangement of the plurality of pin-through bond magnets 1 is provided, but the annular arrangement may be provided over a plurality of stages via a yoke material.

  11 and 12 are a perspective view and an exploded view showing still another example of the magnet structure according to the present invention. Although this magnet structure 4 has a different number of holes from the examples of FIGS. 9 and 10, one end of each pin 12 in one ring-shaped pin through-type bonded magnet 1 having eight pins 12. The portion 12 a is fitted into the corresponding hole 42 of the annular yoke member 41, and the other end 12 b of each pin 12 is fitted into the corresponding hole 44 of the bottomed cylindrical container 43. Have. Such a ring-shaped pin penetration type bonded magnet 1 is integrally formed in a ring shape in advance, and is suitable for a relatively small motor using a bonded magnet having an inner diameter of 10 mm to 100 mm. Further, when the magnet is thick, the pin 12 may be a magnetic pin (for example, an iron pin) in consideration of the demagnetization of the magnet and the amount of magnetic flux.

  Although illustration is omitted, each pin 12 in one ring-shaped pin through-type bond magnet 1 having eight pins 12 is different in the number of holes, similar to the example of FIGS. 9 and 10. One end 12a of the pin 12 is fitted into the corresponding hole 46 of the upper annular yoke member 45, and the other end 12b of each pin 12 is inserted into the corresponding hole 48 of the lower annular yoke member 47. The magnet structure may be configured by fitting.

  In such a magnet structure 2, 3 or 4, an armature is disposed in an internal space surrounded by a plurality or a single pin through-type bonded magnet 1 to constitute a magnet motor. In contrast to this, an armature may be provided outside the annular array of the plural or single pin-penetrating bond magnets 1.

  In the embodiment described above, one segment-shaped pin through-type bond magnet 1 has two pins 12, and one ring-shaped pin through-type bond magnet 1 has eight pins 12. The number of pins 12 provided in one segment-shaped pin through-type bond magnet 1 may be three or more, and one ring-shaped pin through-type bond magnet 1 is provided. The number of pins 12 may be other than eight.

  Moreover, although embodiment mentioned above demonstrated the structure in which the bond magnet main body 11 made | forms a bow shape as a segment shape, the bond magnet main body may comprise the kamaboko shape. Further, as described above, the bonded magnet body 11 may have a ring shape. The present invention can be applied to all bonded magnets having a light, thin and small shape (segment shape or ring shape).

  The disclosed embodiments should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 Pin penetration type | mold bond magnet 2,3,4 Magnetic structure 11 Bond magnet main body 12 Pin 12a One end part 12b The other end part 12c Indentation 21 Dice 22 Upper punch 22a Upper punch hole 23 Lower punch 23a Lower punch recessed part 24 Cavity 25 Magnetic powder for bonded magnet 41, 45, 47 Yoke material 42, 46, 48 hole

Claims (6)

A segment-shaped or ring-shaped bonded magnet body;
A pin penetration type bond magnet comprising: a plurality of pins integrally penetrating the bond magnet body in such a manner that both end portions protrude from the bond magnet body.   The pin penetration type bond magnet according to claim 1, wherein the volume of said pin is 10% or less of the whole.   The pin penetration type bonded magnet according to claim 1, wherein a depression is formed in a central portion of the pin.   4. The pin-penetrating bond magnet according to claim 1, wherein the bond magnet main body includes a magnetic powder of an RTB-based alloy and a thermosetting resin. 5. One or more pin-penetrating bond magnets according to any one of claims 1 to 4,
A magnet structure comprising: a yoke body having a plurality of holes into which one end of each of the one or a plurality of pin through-type bonded magnets is fitted. Using a compression molding machine with an upper punch, a lower punch, and a die, manufactures a pin-through type bond magnet in which both ends protrude from a segment-shaped or ring-shaped bonded magnet body and a plurality of pins penetrates integrally. A method of manufacturing a pin-through bond magnet
The upper punch is provided with an upper punch hole through which a pin is inserted, and the lower punch is provided with a lower punch recess for receiving one end of the pin,
Producing a kneaded product of magnetic powder and thermosetting resin;
Placing a pin in the lower punch recess,
Lowering the lower punch to form a cavity between the die and the lower punch;
Filling the prepared kneaded material into the formed cavity;
Raising the pin and passing a part of the pin through the upper punch hole;
And lowering the upper punch and / or raising the lower punch to compress the kneaded material filled in the cavity.

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