JP3508166B2 - Resin-sealed electromagnetic winding - Google Patents

Description

Description: BACKGROUND OF THE INVENTION This resin-sealed electromagnetic winding is assembled into an armature together with members such as a commutator, a shaft, and a bearing.
After being assembled into a motor together with a field magnet member, a brush, and the like, it is used, for example, in the field of electrical components. 2. Description of the Related Art The reliability of an armature in which a resin-sealed electromagnetic winding is assembled together with components such as a commutator, a shaft, and a bearing often depends on the performance of a sealing resin itself. In particular, the performance of the above sealing resin has an important effect on the reliability of the so-called ironless type of armature, which is formed by winding a self-fusing insulated wire to form an electromagnetic winding and sealing with resin. Exert. [0003] When an armature referred to as an ironless type is used as a motor having a relatively high output of several tens of watts, for example, in the field of electrical components, the armature at high temperatures of up to 80 ° C is required. In many cases, a driving operation that repeatedly starts and stops frequently is required. In this case, the sealing resin must support the electromagnetic winding in a state where it is exposed to a temperature range of about 200 ° C, which is close to the heat resistance limit, and the dimensional stability, thermal stability, and heat resistance deterioration of the resin-sealed electromagnetic winding Performance such as performance is important to ensure the reliability of the motor. Therefore, many ideas and proposals for ensuring the reliability of these motors have been made for resin-sealed electromagnetic windings. For example, Japanese Patent Application Laid-Open No. 54-26403 discloses a proposal for securing the reliability of a motor by using an isocyanate compound having a uretdione ring, an epoxy compound, and a heterocycle-forming catalyst as effective components as a sealing resin for an electromagnetic winding portion. Has been done. In addition, JP-A-60-25
In the 5030 publication, 70% by weight is used as the sealing resin for the electromagnetic windings.
An allylic unsaturated polyester resin having a trifunctional triazine compound containing the above nonmagnetic inorganic filler has been proposed. In this type of resin-sealed electromagnetic winding, including JP-A-54-26403, a large amount of a nonmagnetic inorganic filler such as calcium carbonate, alumina, silica, fused silica glass, or zircon silicate is mixed into a resin. The reason is that the dimensional stability and heat dissipation of the resin-sealed electromagnetic winding are improved by reducing the difference in thermal expansion between the conductor of the electromagnetic winding and the resin, and by increasing the thermal conductivity of the resin. In order to ensure the reliability of the system. [0005] The above-described armature having a coreless structure and a rare earth magnet which is a magnet plumbite type ferrite sintered magnet generally used as a field magnet as a means for responding to a high output of a motor. (B)
Although it is conceivable to improve the magnet characteristics represented by H) max, the consistency between the magnet characteristics and economy is poor. The armature having a coreless structure has a magnetic gap in addition to a mechanical gap with the field magnet due to the magnetic circuit configuration. However, the armature has a magnetic permeability to the sealing resin without impairing the reliability of the electromagnetic winding. , The magnetic resistance of the electromagnetic winding portion can be reduced, and the output of the motor can be increased. It is conceivable that a part or all of the nonmagnetic inorganic filler is replaced with a soft magnetic ferrite powder or an iron soft magnetic powder having an average particle diameter of 10 μm or less. Particles of soft magnetic ferrite are several μm
However, it is chemically stable and has a high electric resistance, but its saturation magnetization Is is low and its Curie temperature Tc is as low as 300 ゜ C. As a member in the field of electrical equipment with a degree of C, the magnetic properties are severely degraded and cannot be used. In addition, the saturation magnetization Is is high, the Curie temperature Tc is high, and the influence of the magnetic properties on the temperature is small in the iron-based soft magnetic powder, but the metal powder of 50 μm or less has a large specific surface area and is chemically active. Is difficult to handle. Further, metal powder having an average particle size of several μm is very expensive and is not economically suitable. According to the present invention, the magnetic resistance of the electromagnetic winding portion is reduced by imparting permeability to the sealing resin without impairing the reliability of the electromagnetic winding portion, which is an armature component of the ironless structure. It is intended to respond to the demand for higher output motors that are used when the temperature of the electromagnetic winding is around 200 ° C. The present invention provides the following (a):
(B) an allyl-based unsaturated polyester resin which is composed of groups (c) and which is a solid at room temperature and contains 5 to 40% by weight of an allyl-based copolymer monomer; Non-magnetic inorganic filler and particle size
In a non-magnetic inorganic filler (c) additive in which the ratio of the non-magnetic inorganic filler of 50 μm or more is 70:30 to 30:70, and in a sealing resin in which the group (b) is 70% by weight or more of the composite. Part or all of the non-magnetic inorganic filler having a particle diameter of 50 μm or more, that is, 15% by volume or more and less than 40% by volume of the total amount of the sealing resin is replaced with an iron-based soft magnetic material having a particle diameter of 53 to 250 μm and at least an electromagnetic winding This is to impart magnetic permeability to the resin-sealed electromagnetic winding in which the wire portion is sealed. It is desirable to use atomized iron powder as the iron-based soft magnetic material. Hereinafter, the present invention will be described in more detail. First, the iron-based soft magnetic material having a particle diameter of 53 to 250 μm referred to in the present invention refers to iron powder or iron-based magnetic powder such as silicon iron, permalloy, and sendust. It is desirable to use atomized iron powder having a spherical shape and a relatively small specific surface area. The allylic unsaturated polyester resin of the group (a) referred to in the present invention is a mixture of an unsaturated polyester alkyd and an allylic copolymerizable monomer solution, and contains various additives such as a polymerization inhibitor. Added as needed.
Allyl-unsaturated polyester resin is preferred because its polymerization curing is a typical radical reaction, it is fast-curing, and it is polymerization-inactive at room temperature due to the resonance of allyl groups. This is because they are advantageous in properties and storage stability of the resin. The unsaturated polyester alkyd is a saturated carboxylic acid, an anhydride thereof, or a dialkyl ester thereof and an unsaturated dicarboxylic acid as a carboxylic acid component.
It is produced by an esterification reaction using the anhydride and glycol as raw materials. As the saturated dicarboxylic acid, orthophthalic acid, phthalic anhydride, isophthalic acid, tetra and hexahydrophthalic acid can be used, but terephthalic acid is preferable. Examples of the unsaturated dicarboxylic acid include fumaric acid, maleic acid, itaconic acid, citraconic acid and the like. Glycol components include ethylene glycol, 1.2- and 1.3-propanediol, 1.3- and 1.4-butanediol, diethylene glycol, dipropylene glycol, neopentyl glycol, alkylene oxide adducts of bisphenols, halogens And alkylene oxide adducts of hydrogenated bisphenol. Such an unsaturated polyester alkyd is desirably a solid having a melting point of room temperature or higher. As the allyl-based copolymerizable monomer as one main component, diallyl phthalate, triallyl isocyanurate, triallyl cyanurate and the like can be used. On the other hand, the inorganic fillers belonging to the group (b) include:
It consists of a mixture of non-magnetic inorganic fillers of 20 μm or less and 50 μm or more, and the mixture ratio is in the range of 70/30 to 30/70% by weight. Mixing ratio of non-magnetic inorganic filler of 20μm or less
If it is more than 70% by weight, the impact resistance and burnout characteristics of the obtained resin-sealed electromagnetic winding are impaired. Be impaired. As the above-mentioned non-magnetic inorganic filler, calcium carbonate, alumina, silica, fused silica glass, zircon silicate, and the like can be appropriately used. On the other hand, the additives belonging to the group (c) include a polymerization initiator for the allylic unsaturated polyester belonging to the group (a), an internal mold release agent, a lubricant, a pigment, a reinforcing agent and the like. (B) Various additives used to smoothly seal the composite consisting of the group with the resin for the electromagnetic winding. For example, dicumyl peroxide, t-butyl perbenzoate, 2,5-dimethyl-2,5-di-t (butylperoxy) hexane or the like is used as a polymerization initiator, and an internal mold release agent is used. There are higher fatty acids, higher alcohols or higher fatty acid esters and metal soaps,
As the lubricant, higher fatty acids such as capric acid, caprylic acid, mistyric acid, palmitic acid, stearic acid, behenic acid and the like for the purpose of ensuring the fluidity of the unsaturated polyester resin during melting as disclosed in JP-B-62-10538. Is esterified with pentaerythritol, and examples of the reinforcing agent include glass fiber and organic fiber. In addition, various additives such as carbon black and antimony trioxide which usually constitute the thermosetting resin composition may be appropriately used as needed. It is important that the mixing ratio of the resin composition comprising the groups (a), (b) and (c) is at least 70% by weight of the resin composition in the group (b). If it is lower than this, not only is the thermal shock resistance and durability of the obtained resin-sealed electromagnetic winding significantly impaired, but also it becomes difficult to maintain and secure desired dimensional accuracy. The mixing method of the groups (a), (b), and (c) and the resin composition components appropriately selected from the groups (a) and (c) satisfy the characteristics and reliability of the resin-sealed electromagnetic winding. It is determined in the range to do. As described above, an iron-based soft magnetic powder having a particle diameter of 53 to 250 μm, an unsaturated polyester alkyd, an allylic copolymerizable monomer, a lubricant, a polymerization initiator, a reinforcing agent, a release agent,
Additives, such as non-magnetic inorganic fillers and pigments, which are appropriately added as necessary, may be kneaded at once. Embodiments of the present invention will be described below. (1) Preparation of sealing resin 19.81% by volume of unsaturated polyester alkyd, 5.78% by volume of diallyl phthalate monomer, dicumyl peroxide
0.25% by volume, glass fiber 8.16% by volume, pentaerythol / C17 triester 2.69% by volume as a basic resin component,
The surface-treated atomized iron powder having a particle size of 53 to 250 μm, calcium carbonate having an average particle size of 4 μm, and calcium carbonate having a particle size of 53 to 250 μm were weighed as shown in Table 1. The weighed components are first added at room temperature to an unsaturated polyester alkyd, diallyl phthalate monomer, dicumyl peroxide, 53-250μ.
m atomized iron powder, average particle size 4 μm calcium carbonate,
After mixing calcium carbonate with a particle size of 53 to 250 μm, the mixture was kneaded at 80 to 90 ° C. by a roll mill, and when it became uniform, glass fiber and pentaerythol / C17 triester were sequentially added and kneaded to obtain a sealing resin. . [Table 1] (2) Preparation of Electromagnetic Winding A self-fusing insulated wire having a conductor diameter of 0.50 mm was wound, and the winding end was electrically connected to a commutator piece. Next, the non-winding ends were arranged radially in the radial direction to obtain flat electromagnetic windings. However, the number of windings is 13, and the number of windings is 23. (3) Resin Sealing of Electromagnetic Winding Using the sealing resin prepared in (1), the electromagnetic winding part of (2) is sealed by transfer molding, and the resin-sealed electromagnetic winding shown in FIG. A wire was made. In FIG. 1, 1A is a sealing resin,
1B is an electromagnetic winding and 1C is a commutator. The molding conditions were: injection temperature 90 ~ 100 ゜ C, injection pressure ~ 100kgf / cm ² , mold temperature
150 ° C ± 5deg, curing time 120s, magnetic circuit distance of main interlinking part of resin-sealed electromagnetic winding after motor assembly is 2.40mm,
The outer diameter of the resin-sealed electromagnetic winding is 94.8 mm. Of these, Example 4 shown in (Table 1) lacked moldability, and was brittle after curing and had insufficient mechanical strength. (4) Motor characteristics An armature in which a shaft and a bearing are mounted on the resin-sealed electromagnetic winding of (3) is inserted into a motor magnetic circuit formed by a field magnet and a magnetic conductive bracket. (Table 2) shows the measurement results of the induced voltage, the starting torque, and the current at 2.0 kg-cm (ST) when rotating at 3000 rpm. [Table 2] (5) Temperature Characteristics FIG. 2 shows the temperature characteristics of the magnetic characteristics of the sealing resins of Examples 1, 2 and 3 and Comparative Example 2. As shown in FIG. 2, in Comparative Example 2 at 200 ° C., which is the maximum electromagnetic winding temperature, the magnetic properties at room temperature are reduced to about / 3, and accordingly the magnetic permeability of the sealing resin is reduced. On the other hand, in Examples 1, 2, and 3, even at 200 ° C., the magnetic properties are slightly reduced, and the magnetic permeability of the sealing resin can be maintained substantially the same as at room temperature. As described above, the first, second, and third embodiments are expected to increase the output of the motor at an electromagnetic winding temperature of about 200 ° C. According to the present invention, a part or all of the non-magnetic inorganic filler having a particle diameter of 50 μm or more among the non-magnetic inorganic fillers which have been frequently used in the sealing resin of the resin-sealed electromagnetic winding is used. ~ 2
By substituting iron-based soft magnetic powder of 50 μm, magnetic permeability is imparted to the sealing resin. In addition, the magnetic permeability is maintained at a high temperature, and it is possible to increase the output of the motor up to a high temperature range.

[Brief description of the drawings] FIG. 1 is a configuration diagram of a resin-sealed electromagnetic winding. FIG. 2 is a temperature characteristic diagram of magnetic characteristics of a sealing resin. [Explanation of symbols] 1A sealing resin 1B Electromagnetic winding 1C commutator

Continuation of front page (72) Inventor Hisaka Kataoka 1006 Kazuma Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd. (56) References JP-A-3-195773 (JP, A) JP-A-1-304150 ( JP, A) JP-A-60-255030 (JP, A) JP-A-58-206639 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02K 3/44

Claims (1)

(57) [Claim 1] It is composed of the following groups (a), (b) and (c), and (a) contains 5 to 40% by weight of an allylic comonomer. The ratio of the non-magnetic inorganic filler having a particle diameter of 20 μm or less to the non-magnetic inorganic filler having a particle diameter of 50 μm or more is 70: 3, which is a solid at room temperature.
0 to 30 : 70 % by weight of non-magnetic inorganic filler (c) additive and (b) sealing resin having 70% by weight or more of the composite, non-magnetic inorganic filler having a particle diameter of 50 μm or more Is a resin-sealed electromagnetic winding in which a part or the whole of is replaced with an iron-based soft magnetic material having a particle diameter of 53 to 250 μm and at least an electromagnetic winding part is sealed, and the iron-based soft magnetic material to be further replaced is atomized.
Iron powder, and the replacement amount of the atomized iron powder is 15 volumes of the total amount of the sealing resin.
% Or more and less than 40% by volume.
Electromagnetic winding .