JPS6323535A - Manufacture of magnet-integrated coreless armature - Google Patents

Abstract

PURPOSE:To obtain an annular multipolarized magnet which can respond accurately to controlling operation by pressurizing, melting and curing thermally polymerizable resin magnet composition made of magnet powder thermally softened by thermal conduction from a metal mold in advance, glass fiber and resin composition. CONSTITUTION:A molded cured material 4b of a thermally polymerizable resin magnet composition is obtained by thermally softening the composition by means of thermal conduction from a metal mold and the molding pressure of the composition 3 for sealing an armature winding 1, molding it in a predetermined state, and fusion-bonding and curing it before gelling the composition 3. The composition 3 comprise 70 - 90wt.% of magnet powder, 1 - 10wt.% of glass fiber, and 10 - 20wt.% of resin composition. According to this manufacturing method, a highly accurate annular multipolarized magnet can be efficiently produced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to the armature of ironless motors, especially ironless motors for control that are often used in the OA field. The thermopolymerizable resin magnet composition, which has been heat softened in advance, is directly pressed by the molding pressure of the thermopolymerizable resin that seals the parts, and the magnets weld and harden together before both thermosetting resin components gel. This relates to a method for manufacturing an integrated electrocardiogram connector.

Conventional technology Ironless motors are often used in control fields that take advantage of their extremely fast control response to perform incremental operations (often used in control fields where pulse motors cannot follow the same characteristics. The ironless core armature is made by sealing an armature winding made of insulated wire or self-bonding insulated wire with a thermopolymerizable resin composition, and adding an annular multipolar magnet to the thermopolymerizable resin composition. (FG) bonded via a magnetic shielding member as necessary has been put into practical use.Such an annular multipolar magnetized magnet rotates together with the armature.
This operation is performed by sequentially feeding back signals to the control circuit via a Hall element or a magnetoresistive element facing the magnetized surface.

- The characteristics and reliability of the above-mentioned ironless motor are usually largely due to the armature. In particular, when performing high-frequency and high-precision control operations, in order to maintain motor function, the stability of the thermopolymerizable resin composition that seals the armature winding at high temperatures and the annular multipole bonding are important. The dimensional accuracy of the magnetized surface of the magnet with respect to the armature axis is important.

Conventionally, the thermopolymerizable resin composition for sealing armature windings has generally been a multi-component composite material consisting of an epoxy resin, a filler, an internal mold release agent, and other additives added as necessary. 1 was used. Therefore, one annular multi-pole magnetized magnet is a general MOF e 12018 (where M is one or more selected from Ba, Sr, etc., and 11 is an integer from 45 to 6.2). The indicated ferrite magnet powder was mixed with 11 g of thermoplastic such as polyamide resin (/I
So-called thermoplastic resin magnets, which are injection molded composites dispersed and molded in fat, were used.

The thermoplastic resin 11t'f magnet was adhered to the surface of a molded cured product of a thermopolymerizable resin composition in which the armature winding had been previously sealed, via a magnetic shield part if necessary.

First, the reason why an epoxy resin composition is preferably used as a thermopolymerizable resin composition for sealing armature windings will be described.

It is well known that epoxy resins can yield polymerized cured products with excellent heat resistance, mechanical strength, and chemical resistance, and that they have excellent compatibility with armature windings. Among these, the property of relatively slow polymerization and curing through ring-opening polymerization is advantageous for obtaining iron-core armatures with little curing distortion, high dimensional accuracy, and thermal shock resistance. Furthermore, since the melt viscosity when sealing the armature winding is low, it is easy to seal the armature winding with a dense structure, and therefore the armature winding is less deformed and the motor characteristics are R+I#. This is because it is advantageous.

Furthermore, the low melt viscosity means that fillers such as alumina, aluminum hydroxide, Silino J1 zirconium silicate, etc.
Since it is possible to add a relatively large amount of If the thermal conductivity of the composition is relatively high, it is advantageous for maintaining and ensuring a practical dimension of kh degree as a coreless armature.

Problems to be Solved by the Invention As mentioned above, the epoxy resin composition is an important component of the ironless armature to ensure high reliability and durability as a motor, but on the other hand, the polymerization and curing of the epoxy resin is difficult. The fact that the process progresses relatively slowly has been a serious drawback in terms of productivity from the point of view of the armature winding sealing operation.

On the other hand, the fact that the annular multi-pole magnetized magnet is bonded directly to the armature winding portion, but via the magnetic shield section 4A, which is used as necessary, makes it possible to Not only was it difficult to ensure dimensional accuracy for the child shaft, but the work itself was an obstacle from a productivity standpoint.

The variation in the dimension ti~ degree of the magnetized surface of the annular multi-pole magnetized magnet with respect to the armature axis does not necessarily mean the variation in the air gap between the pole element and the magnetoresistive element, so the control circuit/uniformity 5- It was difficult to continuously feed back such signals, and it did not have a significant effect on motor characteristics, especially uneven rotation and wow and flutter.

SUMMARY OF THE INVENTION An object of the present invention is to provide a manufacturing method for extremely efficiently producing a highly accurate annular multi-pole magnetized rock capable of responding to high-frequency, monthly high-precision control operations.

Means for Solving the Problems The present invention provides at least the following (a) which has been thermally softened by heat conduction from a mold by molding pressure of a thermopolymerizable resin composition that seals at least the armature winding portion. (b).

The thermopolymerizable resin magnet compositions of group (c) are pressurized to weld and harden together before both thermosetting components become gelatinized.

(a) Magnet powder 70-90% by weight (b) Glass fiber 1-]O weight% (c) (!J fat silk substitute 1
0 to 20% by weight action First, the armature winding referred to in the present invention is a winding wound with insulated wire or self-bonding insulated wire, and the terminal of the winding is usually connected to the commutator. It refers to something that is connected. The shape of the armature winding may be any shape, from a flat shape to a cup shape, based on the design philosophy of the ironless motor. Furthermore, the armature winding may include the armature shaft as well as the commutator.

Next, the thermopolymerizable resin composition referred to in the present invention may be an epoxy resin, but from the viewpoint of ensuring productivity,
Unsaturated polyester resins that cure by a typical radical polymerization mechanism as disclosed in Japanese Patent No. 0-255030 are preferred. The preferred unsaturated polyester resin mentioned here is allyl copolymerization of unsaturated polyester alkyd 1
1-monomer solution, to which various additives such as polymerization inhibitors are added as necessary. The unsaturated polyester alkyd herein is composed of an unsaturated dicarboxylic acid as a carboxylic acid component and, if necessary, a saturated dicarboxylic acid, and a glycol component as an alcohol component. Examples of unsaturated dicarboxylic acids include fumaric acid, maleic acid, itaconic acid, and citraconic acid. As the saturated dicarboxylic acid, orthophthalic acid, isophthalic acid, etc. can also be used, but terephthalic acid is preferable. The reason why terephthalic acid is preferable is that its molecular structure is symmetrical, making it a linear chain rather than an unsaturated polyester alkyd, so it has high reactivity with copolymerizable monomers without increasing the amount of unsaturated acid, and its cured product This is because the heat resistance is excellent. Furthermore, because of its high crystallinity, it is non-adhesive at room temperature and can be easily obtained as a solid, making it easy to handle. In addition, glycol components include ethylene glycol 2- and 1,3-propanediol, ].3- and 1,4-butanediol, diethylene glycol, dipropylene glycol, neopentyl glycol, bisphenols and their alkylene oxide adducts, Examples include hydrogenated bisphenols and their alkylene oxide adducts, alkylene oxide adducts of halogenated hisphenols, and 1,4-cyclohexanedimethanol.

2. As the copolymerizable monomer solution of the unsaturated polyester alkyd, an allyl copolymerizable monomer is used. The reason why allyl-based copolymerizable monomers are preferred is that they are extremely inactive at room temperature due to the resonance (degenerative chain transfer reaction) of the allyl groups, so that products with excellent storage stability can be obtained.

The above unsaturated polyester resins include calcium carbonate, fused silica, clay, talc, zirconium silicate, alumina,
It is kneaded with inorganic granular fillers such as aluminum hydroxide, silica sand, and agarite, an internal mold release agent, a reinforcing agent, a coloring agent, a polymerization initiator, etc. in a conventional manner to form a multi-component composite material. These constituent components and their specific compositions are appropriately determined within a range that satisfies the characteristics and reliability of the iron-core armature.

Next, (a), (b), (c) 3 referred to in the present invention
Basically, the thermopolymerizable resin magnet composition consisting of the group is preferably one that is compatible with at least the thermopolymerizable resin component of the thermopolymerizable resin composition that seals the armature winding. Therefore, for example, if the thermopolymerizable resin of the thermopolymerizable resin composition is an unsaturated polyester resin, it is desirable to use the same type of resin. Below, (a) and (b).

−9= (c) The three groups will be explained individually.

Group (a): Magnet powder - 70 to 90% by weight, the magnet powder referred to in the present invention has the general formula MOFB+20+e (where M is one or more selected from Ba, Sr, etc., and n is 4.5 to 6.2) or Sm (co, Co.

Fe, M) n (where M in the formula represents group ■, group V of the periodic table,
1 or 2 or more elements belonging to group Ⅰ, n is 5 to 9
It is possible to use all magnet powders that are generally used as magnet materials for resin magnets, such as rare earth cobalt magnet powders (integers).

Moreover, the surface of these magnet powders may be treated with carbon functional silane or organic titanate compound.

The above magnet powder is 70 to 90% by weight of the thermopolymerizable resin composition.
Occupy. If it is less than 70% by weight, the magnetic properties as a ring-shaped multipolar magnetized magnet will be insufficient, and if it exceeds 90% by weight, the magnetic flux after multipole magnetization will not be homogeneous due to large variations in magnetic properties. Live. In addition, thermal polymerization P4, which seals the armature winding due to decreased fluidity, has a good surface condition in terms of molding pressure of the resin silk composition and heat conduction from the mold.
This is because it is no longer possible to obtain a molded and cured product of a homogeneous thermopolymerizable resin magnet composition.

Group (b)...Glass fiber 1~]0% by weight The glass fiber referred to in the present invention is usually alkali-free glass fiber with a single fiber diameter of about 10μ■, to which carbon functional silane is added. It is preferable that the raw material is spun to a kneading degree of 400 strands using a sizing agent, and the strands are knotted to a knot of 0.5 to 61 In. However, it is necessary to homogeneously disperse the glass fibers in the thermopolymerizable resin magnet composition. Such glass fibers account for 1 to 10% by weight of the thermopolymerizable resin magnet composition. If it is less than 1% by weight, not only will the thermal polymerizability of the molded cured product of the 61-fat magnet composition decrease, but also cracks may occur on the magnetized surface in iron-core armatures that are used in combination with magnetic shielding members. These cracks cause extreme fluctuations in the magnetic flux level on the magnetized surface, resulting in a significant deterioration in controllability.On the other hand, if it exceeds 10% by weight, the fluidity of the thermopolymerizable resin magnet composition will deteriorate. Due to the reduced molding pressure of the thermopolymerizable resin composition that seals the armature windings and the heat conduction from the mold, it becomes difficult to obtain a homogeneous molded cured product with a good surface condition. Furthermore, localized aggregation of glass fibers causes extreme fluctuations in the magnetic flux level on the magnetized surface, especially in fine magnetization with a magnetization width (pitch between poles) of 50 μm or less, resulting in a significant loss of controllability. have a significant impact.

(c) Resin composition - 10 to 20% by weight The resin composition referred to in the present invention is one in which magnet powder and glass fibers are uniformly dispersed within a range that satisfies motor characteristics and reliability. This makes it a resin magnet composition. Such resin components are divided into a thermopolymerizable resin component and an additive component such as a processing aid. It is preferable that the thermopolymerizable resin component basically be compatible with the thermopolymerizable resin component of the thermopolymerizable resin composition that seals the armature winding. Thermal polymerization 11 thus sealing the armature winding:
If the at fat silk synthetic thermopolymerizable resin component is an allyl unsaturated polyester resin, it is preferable that the thermopolymerizable resin component of the thermopolymerizable resin magnet composition is also an allyl unsaturated polyester resin. As one of the additive components, a higher alcohol tetramodal, higher fatty acids, higher fatty acid esters, or metal soaps of fatty acids can be used as a processing aid, as appropriate. These must be used appropriately depending on the kneading method of the thermopolymerizable resin magnet composition and the cross-wire conditions, and must be within a range that does not seriously affect the maintenance and assurance of motor characteristics and reliability. It goes without saying that the additive components are not limited to the processing aids mentioned above.

Example Hereinafter, the present invention will be explained in more detail using Examples.

However, the present invention is not limited to the examples.

First, FIG. 1 shows the configuration of a magnet-integrated coreless armature, which is the counterpart of the present invention. In the figure, reference numeral 1 denotes an armature winding in which a self-bonding insulated wire is wound in a flat shape. 2 is a commutator,
It is electrically connected to the armature winding 1. 3 is a molded and cured product of a thermopolymerizable resin composition obtained by sealing at least the armature winding 1, 4a is an annular preformed product of a thermopolymerizable resin magnet composition, and 4-b is a heat emitted from a mold. The thermopolymerizable resin composition 3 that seals conduction and the armature winding 1 is thermally softened and molded into a predetermined state by the molding pressure, and the thermopolymerizable resin composition 3
This is a thermopolymerizable resin magnet ♀■ composite molded and cured product that has been welded and hardened together before gelation. The molded cured product 4b is subjected to multipolar magnetization on the outer circumferential surface as illustrated. Reference numeral 5 denotes a magnetic shielding member provided in an annular shape near the area where both the thermopolymerizable resin magnet composition and the thermopolymerizable resin composition are welded and cured to be integrated. The magnetic shielding member 5 is generally effective in protecting against disturbances caused by multi-pole magnetization caused by field magnets and disturbances caused by shift multi-pole magnetization caused by the reactance of the armature winding 1.
As in this case, it is common to adopt an annular structure along the multipolar magnetized surface. However, the magnetic shielding member 5 is stepped with a small one-hole 5' necessary for both the thermopolymerizable resin magnet composition 4b and the thermopolymerizable resin composition 3 to be welded and hardened together and integrated. There is. The structure of such a through hole 5' is determined within a range that satisfies both the shielding function of the magnetic shielding member 5, the mechanical strength and thermal shock resistance of the magnet-integrated coreless armature, and the motor characteristics and reliability. It is something that Reference numeral 6 indicates an armature shaft, and reference numeral 7 indicates a bearing, which are usually mechanically attached after the molding process of the magnet-integrated coreless armature.

The thermopolymerizable resin components of the thermopolymerizable resin composition 3 and the thermopolymerizable resin magnet composition 4b for sealing the armature winding 1 used in the examples of the magnet-integrated coreless armature as described above are as follows. In both cases, the so-called allylic unsaturated polyester K11 fat, which is an allyl copolymerizable monomer solution of terephthalic acid unsaturated polyester alkyd, was used. Here, in the step of forming the thermopolymerizable resin magnet composition into a molded cured product 4b, the composition
Normally, no magnetic field is applied. Therefore, the concentration of the copolymerizable monomer in the allylic unsaturated polyester resin has no effect on the magnetic properties of the molded and cured product of the composition. In other words, the concentration of the copolymerizable monomer in the allylic unsaturated polyester resin should be within a range that can maintain and ensure motor characteristics and reliability, taking into consideration the handling and workability of the composition or its molded and cured product. decide. In addition, the copolymerizable monomer in the allylic unsaturated polyester resin in the examples was sialyl orthophthalate, and its concentration was 15
%. The reason for setting it at 15% is that the allylic unsaturated polyester resin is solid at room temperature, so it is easy to handle, and the shrinkage rate of the molded cured product of the composition is within a range that does not cause a decrease in mechanical strength. Moreover, it is easy to obtain a material with a good surface condition.

First, the composition of the thermopolymerizable resin composition for sealing the armature winding used in the examples is terephthalic acid-based unsaturated polyester (
1,5,72% by weight>, polymerization initiator (0,1,6% by weight)
〉, inorganic granular filler (75°4-6% by weight), inorganic fibrous filler (6,29% by weight), processing aid (0,79% by weight)
% by weight) and internal mold release agent (1.58% by weight).

Next, the composition of the thermopolymerizable resin magnet composition, which is the key point of the present invention, is divided into groups (a), Cb), and (c), and is summarized in Table 1. However, the table also shows comparative examples of the invention examples. The magnet powder of group a in the table is S r OF e12018
, Group B is glass fiber, Group 0 processing aid component is pentaerythritol CI7 triester, internal mold release agent component is norsium stearate, surface brightener component is polyethylene powder, and chemical fiber component is 3 mm. These are long vinyl strands and do not indicate weight percentages.

-], 7-'' The kneading method for the thermopolymerizable resin magnet silk materials listed in Table 1 is shown in Table 1 with the kneading method using an extruder and the kneading method using an E10-ru as R. After kneading, the thermopolymerizable resin magnet composition was coarsely pulverized to about 7 mesh (see Figure 1, 4). Shape into a ring shape as shown in a. The ease of handling including accuracy at this stage is summarized in Table 1.

However, those that are easy to handle are marked ○, and those that are not so easy are marked ×.
It is. As shown in Table 1, if a chemical fiber component is used as a substitute for the glass fiber in group (b), the handling property will be significantly impaired.

The magnetic properties of the molded and cured product of the above thermopolymerizable resin magnet composition are represented by the maximum energy product (Bl()max) and are summarized in Table 1. If the amount of magnet powder exceeds 90% by weight, the magnetic performance will fluctuate. growing.

Using the above thermopolymerizable resin magnet composition, the armature winding, and the thermopolymerizable resin composition to which it is nailed, a magnet-integrated iron core armature as shown in Figure 1 is manufactured, and the thermopolymerizable resin magnet composition is The appearance of the molded and cured product and the presence or absence of cracks are listed in Table 1, and the molded and cured product with good surface condition and homogeneity is ○.
, otherwise = 18 = thing is ×. Since such surface condition and homogeneity mainly depend on the thermal softening property and fluidity of the thermopolymerizable resin magnet composition, it is important to note that such properties are impaired in the amount of magnet powder exceeding 90% by weight. × becomes.

In addition, the molded cured product of the thermopolymerizable resin magnet composition is rated Q1, and those without cracks are rated x.

Since this crack extends to the magnetized surface, it seriously affects the motor characteristics. Cracks do not occur when the glass fiber content is 1% by weight or more. However, glass fiber is 1
If it exceeds 0% by weight, the appearance of the molded cured product will be poor and the amount of magnetic flux will fluctuate greatly after polishing, which is not preferable.

” 1. Thermal shock resistance of the magnet-integrated coreless armature is 120
℃ and -30℃ 20 times, and it was confirmed that no cracks were generated in the molded and cured product of the thermopolymerizable resin magnet composition.

The above-mentioned magnet-integrated ironless armature is used as a motor, and the representative characteristics of rotation unevenness, wow and flutter, and FG output are as follows.
All are displayed in a table. As is clear from the table =20=, stable motor characteristics can be obtained in the example of the present invention.

Effects of the Invention As is clear from the embodiments described below, the magnet-integrated coreless armature according to the present invention can be used as a control motor, especially when used in combination with a magnetic shielding member, ensuring advanced characteristics and reliability. It is possible. Furthermore, since the thermopolymerizable resin magnet composition is molded into a cured product at the step of sealing the armature winding with the thermopolymerizable resin composition, it can be said to be an extremely rational manufacturing method.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a magnet-integrated coreless armature, FIG. 2 is a cross-sectional view of the main part, and FIG. 3 is an exploded perspective view of the main part. 1... Armature winding, 3... Molded cured product of thermopolymerizable resin composition, 4a... Annular shaped body of thermopolymerizable resin magnet composition, 4゜b... Molded cured product of thermopolymerizable resin magnet composition, 5... Magnetic shielding member. Figure 2 Figure 3

Claims (2)

[Claims] (1) The following (a) which has been thermally softened in advance by molding pressure of a thermopolymerizable resin composition that seals at least the armature winding.
, (b) and (c) groups are pressurized to weld and harden them together before both thermosetting resin components gel. (a) Magnet powder: 70-90% by weight (b) Glass fiber: 1-10% by weight (c) Resin composition: 10-20% by weight (2) A method for manufacturing a magnet-integrated coreless armature according to claim 1, wherein a magnetic shielding member is interposed at the welded portion of the thermopolymerizable resin composition and the thermopolymerizable resin magnet composition.