JPH01243405A - Manufacture of resin magnet structure body - Google Patents

Abstract

PURPOSE:To make an annular type resin magnet small, thin and light, by pressing glanular composite material formed by using binder and Fe-B-R system magnet material (R is Nd or/and Pr), and thermally polymerizing it. CONSTITUTION:Microcapsule binder contains thermally polymerizing resin constituting components as the contents. Glanular composite material is formed by using the above binder and Fe-B-R system magnet material (R is Nd or/and Pr), and pressed in a cavity. While contents of the microcapsule are eluted, a green body is molded, and then the binder components are made a rigid body by thermal polymerization. That is, when the granular composite material is compressed in the cavity on which a retaining member is previously mounted and is turned into a green body, the microcapsule is mechanically destructed, the retaining member is wetted by the content substance, and the green body and the retaining member are unified in a body. Thereby, an annular resin magnet is made small-sized and thin, and assembling characteristics are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method of manufacturing a resin magnet structure used as a rotor member of a so-called permanent magnet motor.

BACKGROUND OF THE INVENTION The shape of the resin magnet to which the present invention is applied is a suitable ring shape,
It has an annular shape such as a cylinder or a C shape, and the corresponding support member also has an annular shape such as a ring shape, a cylinder shape, or a cylinder shape, although it can be provided with an engaging portion if necessary.

R(Co, Cu, Fe, M)n (R is Sm
, rare earth elements such as Ce, M is Group II and Group V of the periodic table.

When a sintered magnet, such as one or a combination of two or more elements belonging to group ① or group Ⅰ, where n is generally an integer of 5 to 9, is formed into an annular shape, it becomes magnetically anisotropic in the radial direction. That is extremely difficult. The main reason for this is that there is a difference in expansion coefficient due to anisotropy during the sintering process.
In particular, in the case of thin-walled annular magnets, the only solution is isotropy. For this reason, the high magnetic performance that would normally exhibit 20 to 30 MGOe is reduced to about 5 MGOe.

Furthermore, in cases such as rotor parts of permanent magnet motors that require a high degree of dimensional accuracy, grinding is required after sintering, resulting in poor yields, and the fact that the main components are Sl and CO makes it difficult to achieve economic efficiency. There is a poor balance between performance and performance.

On the other hand, R(Co*Cu+FeeM)
In resin magnets, the matrix resin absorbs the difference in expansion coefficient of the magnet material which is anisotropic in the radial direction, so it is possible to manufacture annular magnets with radial magnetic anisotropy.For example, in the axial direction 8 in case of magnetic anisotropy
Magnets with magnetic performance of ~10 MGOe are easily obtained. Although the magnetic performance is lower than that of a magnetically anisotropic sintered magnet, the density is reduced by approximately 30%, and it is easy to ensure a high degree of dimensional accuracy. Furthermore, since the mechanical weakness peculiar to sintered magnets is improved, the annular magnet has the advantage of being arbitrarily shaped.

However, the problems to be solved by the invention are as follows:
) Even with resin magnets, it is still not possible to sufficiently address the issues of reducing the size of the annular magnet, making it thinner and lighter, or assembling it with other supporting members, such as those used in rotor members of permanent magnet motors. There was a drawback.

The reason for this will be explained below.

First, when annular magnets are made smaller and thinner, they tend to be subject to restrictions on magnetic performance. Generally R(Co*Cu, Fe
+M) As a means for making a resin magnet magnetically anisotropic in the radial direction, for example, as described in Japanese Patent Laid-Open No. 57-170501, a magnetic yoke and a non-magnetic yoke are combined by surrounding a cavity. , and a mold in which a magnetizing coil is disposed on the outside, or a mold in which a magnetizing coil is embedded in the outer periphery of the cavity. In this method, a high voltage, low current type power source is used to generate a predetermined magnetic field strength within the cavity, and the magnetomotive force is increased. However, in order to effectively focus the magnetic flux excited by the magnetizing coil from the outer periphery of the mold into the cavity by the yoke, the magnetic path length must be made long.Especially in the case of a small annular magnet, a considerable portion of the magnetomotive force is generated. is consumed as leakage magnetic flux. Therefore, radial magnetic anisotropy may not be achieved sufficiently depending on the shape of the annular magnet.

Moreover, cracks may occur in the case of thin-walled annular resin magnets due to volumetric shrinkage due to melting and solidification during molding of R(Co, Cut Fel M)n resin magnets.

On the other hand, the above R(Co, Cu, Fe, M
) When a resin magnet is used as a rotor member of a permanent magnet motor, for example, the annular resin magnet and the shaft are often fixed with a supporting member interposed, rather than directly fixing the shaft to the annular resin magnet. Here, the annular resin magnet and the support member are generally fixed by mechanical fitting or by flowing an adhesive from the outside. This is because it is extremely difficult to integrally mold an annular resin magnet with radial magnetic anisotropy with any non-magnetic or magnetic support member due to constraints on the mold configuration. Therefore, when the annular resin magnet and the support member are mechanically fitted, a gap is required for the adhesive to flow, which poses difficulties in the bonding strength, dimensional accuracy, and workability between the annular resin magnet and the support member. be.

It is clear that the above-mentioned problems have a significant impact on the design concept of the performance and structure of permanent magnet motors, which are the field of application of the present invention.

The present invention provides a method for manufacturing a resin magnet structure that eliminates the obstacles to making annular resin magnets smaller, thinner and lighter due to the lack of shape arbitrariness as described above, and at the same time improves assemblability. This is what I am trying to do.

Means for Solving the Problems The present invention uses one or more types of microcapsules containing a thermopolymerizable resin component as a binder component, and the binder and a Fe-B-R magnet material (however, By compressing the granular composite material (R is Nd or/and Pr) in the cavity, a green body having an integral structure with the supporting member is directly molded while the microcapsule-encapsulated substance is eluted. The binder component is then made into a rigid body by thermal polymerization to form a resin magnet structure.

Here, the form of the granular composite material is to form a granular intermediate with one or more binders other than microcapsules and Fe-B-R magnet material, and then form microcapsules and optionally It is a mixture of various additives.

Further, the supporting member is a ring-shaped laminated electromagnetic steel plate used as a rotor member of a so-called permanent magnet motor, and an annular resin magnet is integrally formed with such a supporting member.

action The present invention will be explained in more detail below.

The thermopolymerizable resin component referred to in the present invention is preferably an epoxy resin composition that is generally used as a binder for resin magnets. Here, the epoxy resin composition includes an epoxy resin, a curing agent that three-dimensionally bridges the epoxy resin, and various additives ranging from non-reactive to reactive, which are added as necessary. Here, the epoxy resin refers to a compound having at least two or more oxirane rings in one molecule, which can be represented by the following general formula.

However, Y in the above formula is a polyfunctional halohydrin, for example, a residue of a reaction product of epichlorohydrin and polyhydric phenol. Polyhydric phenols useful herein include resorcinol and various bisphenols obtained by condensation of phenol with aldehydes or ketones.

A representative example of these bisphenols is 2,2'-
Bisphenol A, 4-4'-dihydroxybiphenyl, which is bis(P-hydroxyphenylpropane).

4,4'-dihydroxybiphenylmethane, 2,2'-
Examples include dihydroxydiphenyl oxide. As the most common epoxy resin, a glycidyl ether type represented by the following general formula can be exemplified.

However, in the above formula, R1 is -H or -CH3, R2,
R3, R41R5, R6+ R71R11l R9 is each independently -H, -CQ, -Br, -F, and A is an alkylene group having 1 to 8 carbon atoms, -S-, -O-.

-8O□-, and n is O or an integer from 1 to 10. In addition, as one curing agent, fatty acid polyamines,
Polyamides, heterocyclic diamines.

Examples include aromatic polyamines, acid anhydrides, aromatic nuclear aliphatic polyamines, imidazoles, organic acid dihydrazides, and polyisocyanates. Further, as various additives to be used as appropriate with the above-mentioned epoxy resin and its curing agent as necessary, there may be mentioned various monoepoxy compounds, fatty acids and their metal soaps, fatty acid amides, and the like.

The microcapsules containing the thermopolymerizable resin component as an encapsulating material can be produced, for example, by a so-called 1n-situ polymerization method in which suspension polymerization is carried out in the presence of the thermopolymerizable resin component.

The monomers used here include vinyl chloride, vinylidene chloride, acrylonitrile, styrene, vinyl acetate, acrylic esters, and various crosslinking agents, which are used to form copolymer microcapsules.

However, the thermopolymerizable resin component used as the encapsulating material must be liquid at least at room temperature and chemically inert with respect to the microcapsules. Further, as for the form of the microcapsules, mononuclear spherical capsules having several to several tens of μm are preferable. Incidentally, the number of thermopolymerizable resin components used as the encapsulating substance may be one or two or more. In addition, the amount of compounds other than the thermopolymerizable resin constituents used as the encapsulating material of the microcapsules is small (it is necessary that the final binder is solid at room temperature).

Next, the Fe-B-R magnet material referred to in the present invention refers to a thin piece produced by a liquid quenching method such as a single roll method as disclosed in JP-A No. 59-64739, or by heat treatment. By doing so, a magnet material for a resin magnet represented by the following compositional formula was obtained.

Fe 10G-x-1/-Z Cox Ry Bz However, in the above formula, 0≦X≦30.10≦V≦28, 2≦2≦12
．． y + z≦34, 6z+y≦34. x, y,
z is the atomic percent of Co, R+B, respectively, and R is N
d or/and Pr. In addition, such Fe-B
The -R magnet material may be mixed with other elements or may have regular partial substitution as long as the characteristics as a permanent magnet material are not impaired.

A granular composite material is prepared by using one or more types of microcapsules containing the above thermopolymerizable resin constituents as a binder component, and using the binder and Fe-B-R magnet material. do. Here, the granular composite material is required to be non-adhesive at room temperature and to have moldability necessary for powder molding.

A particularly preferred form of the granular composite is that the magnetic material is made into a granular intermediate in advance with one or more binder components other than microcapsules, and then microcapsules and, if necessary, are added. Additives are mixed. This is because when the granular composite material is compressed in a cavity preloaded with a support member to form a green body, the microcapsules are mechanically destroyed and the encapsulated material, which is a thermopolymerizable resin composition that is liquid at room temperature, is released. This is because when the components are eluted, the supporting member is easily wetted (and the integrity of the green body and the supporting member is easily ensured by pressure bonding and adhesion).

Example Example 1゜ Hereinafter, the present invention will be specifically explained with reference to Examples.

A 1N copolymer of acrylonitrile and methyl methacrylate was prepared by condensation of epichlorohydrin and bisphenol A in the presence of a glycidyl ether type epoxy resin with a viscosity η of 100 to 160 poises at 25°C.
- Microcapsules were prepared by synthesis using an in-situ polymerization method. This microcapsule has an average particle size of 8
The microcapsules are mononuclear spherical capsules made by μAkebono, and the content of the encapsulated substance in the microcapsules is 75% by weight.

On the other hand, the unique coercive force 1Hc14~1 obtained by the liquid quenching method
5KOe, Nd port with particle size 53-350μm)'67s
3e Add 96 parts by weight of thin flakes to Durran'smp6
The mixture was mixed with 3 parts by weight of a 50% by weight acetone solution of a glycidyl ether type epoxy resin at 5 to 75°C, solvent removed, and ground to obtain a granular intermediate material whose particle size was adjusted to 53 to 500 μι.

The above-mentioned granular intermediate material contains 2 parts by weight of the microcapsules described above, which have the following structure and a particle size of 5 to 10μ.
Bis(hydrazinocarboethyl χ5-isopropylhydantoin NH2O, 45 parts by weight, and calcium stearate 0.2
A granular composite material (I) according to the present invention containing 95.9% by weight of Fe-B-R magnet material was prepared by mixing 0 parts by weight.

FIGS. 1(a) and 1(b) are photographs showing the appearance of the granular composite material (1). As is clear from the figure, Fe-
The B-R magnet materials are Durran'smp65~
It is prepared into granules using solid epoxy resin at 75°C, and on the surface of the granules are microcapsules containing epoxy resin that is liquid at room temperature, epoxy resin curing agents, calcium stearate, and other fine particles. It has an attached structure. Therefore, this granular composite material is non-adhesive at room temperature and has fluidity as a powder molding material.

Next, a support member having an annular shape with an outer diameter of 47.9+n+++ and an inner diameter of 8IIIR and made by laminating 22 electromagnetic steel plates with a thickness of 0.5 mm is loaded into the mold member, and a diameter of 50.2On+n+ is attached to the outer periphery of the support member. An annular cavity was formed. The granular composite material (1) was filled into this annular cavity and compressed at room temperature to form an annular green body.

Next, the annular green body and the support member were demolded together, and then the binder was thermally polymerized at 120° C. for 1 hour. The obtained annular green body was made rigid integrally with the support member.

FIG. 2 shows the above resin magnet structure according to the present invention in which a shaft is assembled to a support member.

In the figure, 1 is a support member, 2 is a resin magnet made rigid integrally with the support member 1, and 3 is a shaft on which the support member 1 is assembled. As is clear from the figure, it is clear that the resin magnet structure can be used as is as a rotor member of a permanent magnet motor.

Table 1 below is a characteristic table showing the outer diameter dimension and the outer circumferential runout with respect to the axis of the resin magnet structure described above.

Table 1 In particular, thin-walled annular Fe-B with a thickness of about 1 mm is directly attached to the outer peripheral part of an annular support member made of laminated electromagnetic steel sheets with an outer diameter of 47.9 m.
-Although it is a resin magnet structure integrally molded from R-based magnet material, a high degree of dimensional accuracy is ensured.

FIG. 3 is a characteristic diagram showing the temperature dependence of the shear strength of the resin magnet and the support member of the resin magnet structure. As is clear from the figure, the shear strength between the resin magnet and the support member decreases at high temperatures, reflecting the properties of the binder in the resin magnet. However, even at 100° C., the weight remains approximately 300 kg, and it is clear that the resin magnet structure is a resin magnet structure in which the resin magnet and the support member are sufficiently integrated and rigid.

FIG. 4 is a photograph of the bonded surface of the resin magnet separated from the support member due to shear failure of the resin magnet structure. From the figure, it can be seen that the microcapsules, which are the binder component, were mechanically destroyed during the step of forming the granular composite into a green body. In this way, the encapsulated substance eluted outside the microcapsule,
It is clear here that the glycidyl ether type epoxy resin having a viscosity η25°C of 100 to 160 poises directly wets the support.

Example 2゜Unique coercive force 1Hc14-15KO obtained by liquid quenching method
e, Nd14Fe7eB with a particle size of 53 to 350 μ-
8 flakes, 97 parts by weight, and the following structure, and a softening temperature of 16
Granules whose particle size is adjusted to 5'3 to 350 μm by mixing with 1.6 parts by weight of a 50% acetone solution of poly P-vinyphenol, an alkenylphenol polymer, at 0 to 170°C, pulverizing, and removing the solvent. It was used as an intermediate. This granular intermediate contains 2.2 parts by weight of the microcapsules used in Example 1, 0.05 parts by weight of BF3:2-methylimidazole complex, and 0.05 parts by weight of calcium stearate.
05 parts by weight to form a Fe-B-R based granular composite (I
I) was adjusted. Next, the outer diameter is 47.9 m, which is the same as in Example 1.
A supporting member having an annular inner diameter of 8++n and made of 11 laminated electromagnetic steel plates having a thickness of 0.5 m was loaded into a mold member, and an annular cavity with a diameter of 50.2+ms was formed around the outer periphery of the supporting member. This annular cavity was filled with the granular composite material (n) and compressed at room temperature to form an annular green body. Next, the annular green body and the support were demolded together, and then the binder was thermally polymerized at 160° C. for 1 hour. The obtained annular green body was made rigid integrally with the support member.

A shaft was assembled to the above resin magnet structure and rotated at a high speed of 8,000 rpm for 6 hours in an atmosphere of 100° C., but no mechanical breakage of the annular resin magnet due to centrifugal force or separation from the support member was observed.

Comparative Example 1 Unique coercive force obtained through solution treatment: 1Hc9.5K Oe
e Ss (Co 0.68
8゜C1o, tot, p6 o, 2nd * Zr 01
017) 7 particles 97 parts by weight, viscosity η25℃100-1
60 poises of glycidyl ether type epoxy resin/1-benzyl 2-methylimidazole (weight ratio 10
:1) 3 parts by weight of the mixture to prepare a compression molding grade R(Co, Cu, Fee M)n resin magnet raw material.

Next, in the same manner as in Examples 1 and 2, the outer diameter was 47°9-2.
Two electromagnetic steel plates with an inner diameter of 8 mm and a thickness of 0.5 m are
Two laminated support members were loaded into a mold member, and an annular cavity with a diameter of 50.2 mm was formed around the outer periphery of the support member. This annular cavity was filled with R(Co, Cu, Fee M)n resin magnet raw material and compressed at room temperature to form an annular green body. However, with this method, it is not only difficult to fill the material into the cavity, but also difficult to remove the annularly molded green body and supporting member from the mold together, and the green body is damaged due to springback of the green body. This results in separation from the support.

Comparative Example 2 Sl with a unique coercive force of 1Hc9.5KOe obtained through solution treatment (Co o, sea, (:uo, tot, )
'e O, 2nd eye.

Zr 0-017)? 92 parts by weight of particles and a relative viscosity of 1.6 (measured with a 0.5%-m cresol solution at 25°C using an Ostwald viscometer) having the following structure: H(NH(
An injection molding grade R(Co, Cu, Fe, M)n resin magnet raw material was prepared by kneading CH2)tlo)nOH with 8 parts by weight of 12-polyamide.

Next, in the same manner as in Examples 1 and 2, the outer diameter was 47°9w.
m, annular with an inner diameter of 8IIIl and a thickness of 0.5 mm
A supporting member in which 11 electromagnetic steel sheets were laminated was loaded into a mold member, and an annular cavity with a diameter of 50.2 nm was formed around the outer periphery of the supporting member. R(Co, Cu, Fe) from a ring gate provided at one end of this annular cavity.

M) N resin magnet raw material was melted and injected, and filled and solidified in the cavity. However, it is not only difficult to fill the thin-walled annular cavity with this resin magnet, but even when it is filled, cracks occur in all the annular resin magnets due to volume shrinkage due to melting and solidification.

Comparative Example 3゜Figure 5 is a perspective view of a rotor member in which sintered ferrite magnets of 4,2MGOe, which are magnetically anisotropic in the thickness direction, are adhesively fixed to the outer peripheral surface of a 0.5w* thick electromagnetic steel sheet laminated support member. It is. However, in the figure, 4 is a support member, 5 is a sintered magnet fixed to the outer peripheral surface of the support member 4 with adhesive, and 3 is a shaft assembled to the support member 4. Here, the outer diameter of the rotor member is 50.2-
This is on the same level as the resin magnet structure according to the present invention shown in FIG. However, the length of the magnet is 1.5 times that of the resin magnet structure according to the present invention shown in FIG. 2, and the volume ratio is 4 times that of the resin magnet structure according to the present invention shown in FIG. Table 2 is a characteristic table when both motors are brushless DC fan motors, which are representative permanent magnet motors.

Table 2: However, the torque and output in the table are at a fan load of 1420 rpm. Note that the maximum load current values in the range of rated voltages of 7 to 35 V were both at the same level below IA. As is clear from the table, the resin magnet structure according to the present invention can be used even in fields where it has been generally difficult to apply annular magnets.

Effects of the Invention As described above, the present invention provides a resin magnet structure that can eliminate the obstacles to miniaturization and thinning of annular resin magnets due to the lack of shape arbitrariness, and at the same time improve assemblability. be able to.

[Brief explanation of the drawing]

Figures 1 (a) and (b) are photographs showing the particle structure of the granular composite material, Figure 2 is a perspective view of the resin magnet structure, and Figure 3 is the characteristics showing the shear strength of the resin magnet and supporting member. 4 are photographs showing the particle structure of the joint surface of the resin magnet with the supporting member, and FIGS. 5(a) and 5(b) are a perspective view and a plan view showing a rotor member of a comparative example. Name of agent: Patent attorney Toshio Nakao and one other person Figure 2″’ Figure 3 Atmospheric temperature °C Figure 5 (a) (b) Procedure amendment method) 1 Indication of case Patent Application No. 63976, filed in 1988 2 Name of the invention Method for manufacturing a resin magnet structure 3 Relationship with the case of the person making the amendment Patent Issued by Colonel Akane Address 1006 Kadoma, Kadoma City, Osaka Name Name
(582) Representative of Matsushita Electric Industrial Co., Ltd.
Akio Tanii 4 Agent 571 Address 1006-5 Kadoma, Kadoma-shi, Osaka Date of amendment order March 28, 1999 6 Detailed explanation of the invention in the specification subject to amendment 7 Contents of amendment ( 1) Correct the "photo" in the 9th line from the bottom of page 14 of the specification to "schematic diagram." (2) Correct "photo" in the second line of page 17 to "schematic diagram". (3) Correct "Photograph" on page 22, line 20 of the same page to "schematic diagram." ■Correct "photo" in the third line of page 23 to "schematic diagram". (5) Revise Figure 1 of the drawing as shown in the attached sheet. (6) Revise Figure 4 of the drawing as shown in the attached sheet.

Claims (3)

[Claims] (1) One or more types of microcapsules containing thermopolymerizable resin components as binder components, and the binder and Fe-B-R magnet material (where R is Nd or /
By compressing the granular composite material formed with (Pr) and Pr) in the cavity, a green body having a structure that is directly integrated with the supporting member is formed while the microcapsule-encapsulated substance is eluted, and then the binder component is A method for manufacturing a resin magnet structure that becomes rigid through thermal polymerization. (2) The granular composite material is made into a granular intermediate by one or more binder components other than microcapsules and Fe-B-R magnet material, and then added to microcapsules and as necessary. The method for manufacturing a resin magnet structure according to claim 1, which is a mixture of various additives. (3) The method for manufacturing a resin magnet structure according to claim 1, wherein the supporting member is a laminated electromagnetic steel plate, and the annular green body is directly integrally formed on the outer periphery of the supporting member.