JPH02164246A - Manufacture of rotor for small electrical rotating machine and manufacturing apparatus thereof - Google Patents

Abstract

PURPOSE:To prevent a defective insulation and a projection of coil at the time of high load and high rotation by filling or covering the coil-inserting groove of a laminated core and a part of the coil end with an insulating resin composition and thereafter heating and hardening the obtained product. CONSTITUTION:The rotating shaft 2 of a rotor 1 is fitted with an armature core 3 and a commutator 4. A plurality of grooves 5 are formed in the outside surface of the armature core 3 and a coil 6 having an end connected with a commutator segment is inserted in the groove 5. Further, an insulating resin composition 7 including the tetraglycidyl ether of tetraphenol novolak phenol resin and inorganic filler is caused to adhere to or fill up the end of the coil 6 and the groove 5 and is hardened at the temperature of 150 deg.C or more. In this case, the resin composition 7 is excellent in heat resistance and insulating properties and does not lower the mechanical strength after heat curing. Thus, it is possible to obtain a rotor being proof against high load and high rotation.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a rotor for a small rotating electric machine, and is made by winding a winding wire around a particularly laminated iron core and fixing it with a resin material or the like with a bolt. This invention relates to a rotor for a small rotating electric machine, a method for manufacturing the same, and a manufacturing device for the same.

[Prior Art] Conventionally, the rotor of a small rotating electric machine, such as a starter motor for an automobile, has been manufactured by attaching a stratified iron core to the rotating shaft, and inserting coils into multiple winding insertion grooves provided on the circumference of the core. For example, a varnish or the like is applied thereon, and this is dried and hardened to fix the coil.

On the other hand, in recent years, as automobiles and the like have become lighter, there has been a strong demand for smaller and lighter in-vehicle equipment, and along with this, rotors of rotating electric machines have also been required to be smaller and lighter. Further, such requirements are not limited to only in-vehicle equipment, but also apply to fields that use small rotating electric machines such as power tools.

However, when the rotor of a rotating electrical machine such as a motor is downsized for boat fishing, the number of revolutions thereof increases, which increases the load on the motor rotor and also increases its current density. Therefore, the temperature rise of the motor rotor is significantly higher than that of conventional varnishes, and conventional varnishes and the like have insufficient heat resistance.

In other words, with conventional varnish etc., the temperature at high loads is 400℃~
If it is exposed to a high temperature of 450° C. for about 10 minutes, it will emit smoke, cracks and blisters will occur, and its insulation properties will decrease as well as its mechanical strength. In particular, in the aforementioned starter motors, etc., when the engine is started, a large current flows through the rotor and the rotor becomes hot, and its rotational speed reaches several thousand revolutions per minute, which causes the problem that the windings may fly out. There was a problem.

In addition, among conventional solvent-based varnishes, there are polyamide-imide and polyimide-based varnishes, but these take a long processing time, have relatively low adhesion strength, and contain N contained in the varnish.
-Methyl-2-pyrrolidone.

It has not been put to practical use because polar solvents such as dimethylacetamide destroy the coating on the enamelled copper wire that serves as the insulating wire.

Powder epoxy is generally widely used in small motors, etc., but it also has poor heat resistance and is difficult to penetrate into the slots of the rotor and the inside of the coil, so it cannot be used under high loads and high rotations as mentioned above. It is not suitable as a mold insulation fixing material for the rotor of small rotating electric machines.

[Problem to be solved by the invention]

In view of the above-mentioned problems in the prior art, the present invention aims to provide a rotor assembly for a small rotating electric machine that does not cause poor insulation between coils and prevent coils from popping out even under high loads and high rotations, and furthermore, to It is an object of the present invention to provide a manufacturing method and manufacturing apparatus suitable for manufacturing a rotor.

[Means to solve the problem]

The first object of the present invention is to rotate a small rotating electrical machine comprising a rotating shaft, a layered core fixed on the rotating shaft, and a coil inserted and fixed in a coil insertion groove formed on the outer periphery of the layered core. In the second step, at least a part of the coil insertion groove of the laminated core and the coil end of the coil are filled or coated with a resin composition containing tetraglycidyl ether of tetraphenol ethane, a novolac phenol resin, and an inorganic filler, and then cured. This is achieved by a rotor for a small rotating electric machine characterized by the following.

A second object of the present invention is to provide a rotor for a small rotating electric machine, which comprises a rotating shaft, a layered core fixed on the rotating shaft, and a coil inserted and fixed in a coil insertion groove formed on the outer periphery of the layered core. In the manufacturing method, after the coil is wound in the coil insertion groove of the layered iron core, at least a part of the coil insertion groove of the layered iron core and the coil end of the coil is wound.

tetraglycidyl ether of tetraphenolethane,
Achieved by a method for producing a rotor for a small rotating electric machine, characterized in that the rotor is filled or coated with a resin composition containing a novolac phenol resin and an inorganic filler, and then the resin composition is cured at a temperature of 150°C or higher. be done.

A third object of the present invention is to rotate a small rotating electric machine comprising a rotating shaft, a layered core fixed on the rotating shaft, and a coil inserted and fixed in a coil insertion groove formed on the outer periphery of the layered core. In the device for manufacturing a child, the coil insertion groove of the laminated core and at least a portion of the coil end of the coil are further filled with a resin composition containing tetraglycidyl ethal of tetraphenol ethane, a novolac phenol resin, and an inorganic filler. Alternatively, the present invention can be achieved by a manufacturing apparatus for a rotor of a small rotating electric machine, which is equipped with a coating means and a thermosetting furnace for curing the resin composition at a temperature of 150° C. or higher.

[Effect]

tetraglycidyl ether of tetraphenolethane,
The resin composition containing the novolac phenol resin and the inorganic filler is in the form of a solid powder at room temperature, and is
It becomes a molten liquid at a temperature of 150°C or higher, and is thermoset at a temperature of 150°C or higher. This resin composition also has

After heat curing, it has excellent heat resistance, does not generate smoke, crank, or blister even at high temperatures of 400°C to 450°C, and does not reduce mechanical strength.

In the present invention, by utilizing such characteristics of the resin composition, in other words, in a rotor of a small rotating electric machine, tetraglycidyl ether of tetraphenolethane and novolac Phenolic resin.

To obtain a rotor for a small rotating electrical machine that does not cause poor insulation or coil protrusion even under high loads and high rotations by filling or coating with a resin composition containing an inorganic filler and curing the same. Can be done.

〔Example〕

Examples of the present invention will be described below.

FIG. 1(a) shows a rotor 1 of a small rotating electrical machine according to the present invention, particularly a starter motor for an automobile. As shown in the figure, this rotor 1 has a rotating shaft 2 rotatably supported in a motor bracket (not shown).
On this rotating shaft 2, an armature core 3 formed into a cylindrical shape by laminating a plurality of steel plates and a commutator 4 are attached. On the outer peripheral surface of this armature core 3, a first
As shown in Figure (b), a plurality of grooves 5 are formed,
A coil 6 is inserted into this groove 5. This coil 6 is made of, for example, a so-called enameled wire coated with enamel, which is shaped into a predetermined shape, and then inserted into the groove 5, and its end is connected to the commutator piece of the commutator 4. Further, an insulating resin composition 7, which will be described in detail below, is adhered to and filled into the end portion of the coil 6 and the coil insertion groove 5, and is cured.

That is, in the present invention, the insulating resin composition 7 not only insulates the coil of the rotor but also fixes the coil. Such an insulating resin composition 7 is a resin composition that is solid at room temperature and contains A) tetraglycidyl ether of tetraphenol ethane, B) a novolac phenol resin, and C) an inorganic filler. After being sprayed on the ends and coil insertion grooves, it is cured at a temperature of 150°C or higher. The spraying method is to powder the solid resin composition and let it fall naturally from above to the rotor 1.
Alternatively, the powdery solid resin composition may be attached to the outer circumference of the rotor 1 by contacting or calendaring the powdery solid resin composition. Alternatively, a mixture of air and a powdered solid resin composition may be sprayed at a certain pressure to adhere the mixture. The rotor treated in this way has no cracks or blisters even when heated from 400°C to 450°C for about 10 minutes, and has excellent adhesion strength at high temperatures, making it suitable for use as a high-speed rotor. In addition, this composition
It has the characteristic of sufficiently penetrating and impregnating the slot and the inside of the winding.

Next, each component of the above resin composition 7 will be explained.

In the present invention, the tetraglycidyl ether of tetraphenolethane represented by formula (1) is used as the tetraglycidyl ether of tetraphenolethane as component A).

Formula (1) diglycidyl ether and its derivatives derived from bisphenol A and epichlorohydrin, if necessary;
Diglycidyl ether derived from bisphenol F and epichlorohydrin and its derivatives, commonly known as epi-bis type liquid epoxy resin, diglycidyl ether derived from polyhydric alcohol and epichlorohydrin, glycidyl ester derived from polybasic acid and epichlorohydrin, and its derivatives, glycidyl ether derived from hydrogenated bisphenol A and epichlorohydrin and its derivatives, 3,4-epoxy-6-methylcyclohexylmethyl-3,4-epoxy-6-methylcyclohexanecarboxylate, dicyclopentanedienoxide,
Vinyl cyclohexene oxide, bis(2,3-epoxycyclopentyl) ether, 3,4-epoxycyclohexylmethyl (3,4-epoxycyclohexane)
Carboxylate, bis(3,4-epoxy-6-methylcyclohexylmethyl) adipate, cycloaliphatic epoxy and its derivatives such as limonene dioxide, methyl-substituted epoxy derived from isobutylene, diethylene glycol diglydyl ether, phenyl glycyl Epoxy compounds such as ethers and butyl glycidyl ether can be used in combination with the tetraglycidyl ether of tetraphenolethane.

As the novolac phenol resin of component B, common novolac phenol resins, cresol novolac resins, etc. can be used.

As the inorganic fabric material of component C), aluminum oxide, quartz powder, talc, mica, calcium silicate, magnesium oxide, etc. are used, and those having a particle size of 1 to 200 μm are preferable.

B) component is A) component 10 from the point of adhesive strength and heat resistance.
It is preferable to use it in a range of 30 to 70 parts by weight relative to 0 parts by weight.

C) component is A) component 10 from the point of viscosity and heat resistance.
It is preferably used in an amount of 50 to 400 parts by weight relative to 0 parts by weight.

As shown in the graph of FIG. 3, the above resin composition is in powder form at room temperature, and when spraying and depositing it on the coils of the rotor 1 and filling it, the rotor 1 must be heated. However, from the viewpoint of workability and pot life, it is desirable to carry out the process at a temperature in the range of 100 to 200°C. After the resin composition adheres to the rotor 1, it is melted by heat and penetrates deep into the slots 5. Furthermore, in order to cure this resin composition, it is necessary to heat it at a temperature of 150° C. or higher. It is best to raise the temperature or add a small amount of curing accelerator to heat and cure quickly.

Next, a method for manufacturing the rotor of the small rotating electric machine shown in FIGS. 1(a) and (b) will be described with reference to FIGS. 2(a), (b), and (c).

First, in FIG. 2(a), the rotor 1 is heated to 170° C. with the heater 10. Fig. 2(b) shows that Fig. 2(a)
This figure shows how the powder of the resin composition 7 at room temperature is allowed to fall naturally from above onto the outer periphery of the heated rotation 1, and is dripped onto the required location of the mold.

The adhered resin composition 7 is melted by the heat of the rotor 1,
Penetrates deep. As shown in FIG. 3, this resin composition 7 is a powder at room temperature, turns into a liquid in a temperature range of 100° C. to 150° C., and becomes a powder again when the temperature is returned to room temperature. Further, this resin composition has the characteristic that it begins to thermally cure when heated to 150° C. or higher, and after curing does not return to a liquid or powder state even if the temperature is lowered. The resin composition 7 that did not adhere to the rotor 1 was
Since it falls without melting, it can be reused.

Next, the rotor 1 molded with the resin composition 7 is thermally cured at a temperature of 150° C. or higher, as shown in FIG. 2(c). In other words, in Figure 1, the heater 11
Heat curing is performed by heating for about 10 minutes in a heating furnace heated to a temperature of .degree.

If the heating temperature required for this thermal curing is lowered, the heating time required for curing will also become longer.

Even when the rotor 1 manufactured as described above is heated to 400° C. or higher, there are no problems such as cracks occurring in the thermoset resin composition 7, gas spouting, or smoke generation. There wasn't. In particular, when used in the rotor of a starter motor for starting an engine, a very large armature current flows for a short time during startup, and the rotor 1 itself is heated to nearly 400 degrees Celsius, making the motor particularly compact. It is significant when However, since the outer periphery of the armature coil was filled and coated with the insulating resin composition, no insulation defects occurred. In addition, the starter motor reaches a high speed of several thousand revolutions and seven minutes when starting, but the resin composition used to mold the coil has excellent heat resistance, and the coil did not fly out due to centrifugal force. .

FIG. 4 shows an apparatus for manufacturing the rotor of the small rotating electrical machine, which implements the manufacturing method described above. In FIG. 4, this rotor manufacturing apparatus is provided with a heating furnace 12, and a spraying equipment 13 is provided on the right side of the heating furnace 12.
A belt conveyor device 14 is provided approximately at the center of the heating furnace 12 and the dispersion equipment 13, and rollers 15 for driving the belt conveyor device 14 are provided at both ends thereof. The heating furnace 12 is divided into upper and lower parts by the belt conveyor device 14, with the upper part serving as a thermosetting furnace 16 and the lower part serving as a total heat furnace 17. That is, a heater 18 is provided above the thermosetting furnace section 16 of the heating furnace 12, and the temperature inside the thermosetting furnace 16 is maintained at 150° C. or higher, which is the temperature necessary for thermosetting the resin composition. . On the other hand, the total heat furnace 1 in the lower part of the heating furnace 12
7 is the melting temperature of the resin composition, 100°C to 20°C.
It is kept within the 0°C range.

The powder resin composition 7 falls and adheres to the end of the coil of the rotor 1 passing through the lower part of the spraying equipment 13 . The falling amount of the resin composition 7 is adjusted to an appropriate amount using a device such as a partition plate. Since the adhered and melted resin composition 7 causes uneven adhesion, a scraping plate or brush 19 is provided for smoothing the surface and removing excess adhered resin.

On the other hand, a tray 20 is provided at the bottom of the spraying equipment 13,
Resin composition 7 that fell without adhering to rotor 1 of resin 7
However, this receiver is received by the tray 20, collected again in the spraying equipment 13, and reused.

Further, on the surface of the belt conveyor device 14, rotor fixing devices 21 for fixing the rotor 1 on the belt are provided at equal intervals, and as shown in FIG. The rotors 1 to be filled are sequentially fixed on the rotor fixing device 21 of the belt conveyor device 14 and introduced into the furnace from the left opening of the total heat furnace 17 of the heating furnace 12.

A VI-VI cross section of this manufacturing apparatus is shown in FIG. As is clear from FIG. 5, the belt conveyor device 14
A gear 23 is attached to the end of the rotating shaft 22 of the roller 15. On the other hand, a gear 25 is also provided on the rotation output shaft of the drive motor 24, and these gears 23 and 25 mesh with each other, so that the rotational force of the drive motor 24 is transmitted to the roller 15 of the belt conveyor device 14. Ru.

Further, as clearly shown in FIG. 5, the rotor fixing device 21 attached to the belt of the belt conveyor device 14 has a loop-shaped end, and the rotating shaft 2 of the rotor 1 is inserted into the loop. The rotor 1 is fixed rotatably. Further, when fixing the rotor 1, sprockets 26 are attached to the left end of the rotating shaft 2, and a chain 27 is hung around the outer periphery of these sprockets 26.

This chain 27 is further connected to a chain drive motor 2.
The rotor 1 is rotated via a sprocket 29 attached to the output shaft of the rotor 1, and thus the rotor 1 moves while rotating in the heating furnace 12 and the spraying equipment 13.

Next, the operation of the above manufacturing apparatus will be described in detail below. In FIG. 4, a belt conveyor device 14 protrudes from the opening on the left side of the heating furnace 12, and a rotor 1 with a coil wound around the outer circumferential loop of a rotor fixing device 21 attached to the surface of the belt. Insert and fix the rotating shaft 2. At the same time, a sprocket 26 (FIG. 5) is attached to the rotating shaft 2, and a rotational drive chain 27 is hung thereon. In this state, the rotor 1 is connected to the belt conveyor device 1.
4 while rotating on the bottom of the heating furnace 12.
It will be introduced in 7. In this total heat furnace 17, the rotor 1
is heated within the temperature range of 100° C. to 200° C., which is the melting temperature of the resin composition, and then introduced into 13 parts of the spraying equipment.

At the bottom of this spraying equipment 13, a powdered resin composition is dropped onto the end of the coil of the rotor 1, and this resin composition adheres to the end of the coil and is melted into the coil inserted into the core groove. It also penetrated.

Mold rotor 1. At this time, as explained with reference to FIG. 5, since the rotor 1 moves while rotating, the dropped resin composition does not concentrate on a part of the rotor 1 and is molded uniformly as a whole. It turns out. Thereafter, the rotor 1 molded with this resin is cleaned with a scraping plate or a brush 19 to remove excess resin particularly from the surface of the core. This rotor 1 is then introduced into a thermosetting furnace 16, where it is thermosetted at a temperature of 150° C. or higher, and the rotor 1 is completed. This completed rotor 1 returns to the opening of the heating furnace 12 again, is removed from the belt conveyor device 14, and is cooled.

In the above manufacturing apparatus, the heating furnace 12 is divided into upper and lower halves by a belt conveyor device 14 that transports one rotor 1 within the furnace. The resin composition is preheated to the melting temperature in a total heat furnace 17 located below the heating furnace 12. In this way, by fully heating the rotor 1 before spraying and filling the resin, the resin composition adheres to the surface of the rotor 1, melts, and penetrates deep into the coil inside the groove. It also penetrates sufficiently.

Further, when an inorganic material such as alumina is used as a filler, it is desirable that the resin composition be taken out in a semi-hardened state in the thermosetting furnace 16. because,
This is because the resin composition becomes too hard after being completely thermoset, making it difficult to cut the surface with a cutting tool or the like. Further, in order to adjust the rotational balance of the rotor 1, when cutting the surface of the iron core, it is desirable to carry out the cutting process while the resin composition is in a semi-cured state, as described above.

Further, as shown in FIG. 4, the excess amount of resin that falls when the resin composition is applied is collected in a tray 20, returned to the spraying equipment 13, and reused.

Therefore, by using the above resin composition as an insulating molding material, it becomes possible to reuse the excess resin composition, thereby minimizing wasteful use of insulating material and making it possible to manufacture small rotating electrical appliances at a lower cost. It becomes possible to manufacture rotors of

〔Effect of the invention〕

As is clear from the above description, according to the present invention, 40
A small rotating machine that can withstand high loads and high rotations without causing smoke, cracking or blistering of the insulating resin even at high temperatures of 0°C to 450°C, without reducing its insulation properties, V and mechanical strength. This has an excellent effect of being able to provide a rotor for an electric machine.

[Brief explanation of the drawing]

FIG. 1(a) is a perspective view showing a rotor of a small rotating electrical machine which is an embodiment of the present invention, FIG. 1(b) is a partial sectional view of the rotor of FIG. 1(a), and FIG. Figure (a). (b) and (c) are explanatory diagrams for explaining the manufacturing method of the rotor of the present invention, and Fig. 3 shows a temperature characteristic graph for showing the characteristics of the insulating resin used for the rotor of the present invention. 4 is a diagram showing a manufacturing apparatus for manufacturing a rotor for a small rotating electric machine according to the present invention, and FIG. 5 is a partial sectional view taken along the line 1--2 at a joint. DESCRIPTION OF SYMBOLS 1... Rotor, 2... Rotating shaft, 3... Armature core, 5 coil insertion groove, 6... Armature coil, 7... Insulating tree 12... Heating furnace, 13... ...Spraying equipment, 14...
- Competition equipment, 16...thermal curing furnace.

Claims (1)

[Scope of Claims] 1. A rotor for a small rotating electric machine comprising a rotating shaft, a layered core fixed on the rotating shaft, and a coil inserted and fixed in a coil insertion groove formed on the outer periphery of the layered core. In the manufacturing method, after the coil is wound in the coil insertion groove of the layered iron core, at least a portion of the coil insertion groove of the layered iron core and the coil end of the coil is coated with tetraglycidyl ethal of tetraphenol ethane, novolac phenol. Powder of resin composition containing resin and inorganic filler,
A method for manufacturing a rotor for a small rotating electrical machine, characterized in that the resin composition is adhered to the rotor while being heated to 100°C or higher, and then the resin composition is cured at a temperature of 150°C or higher. 2. A method for manufacturing a rotor for a small rotating electrical machine according to claim 1, wherein filling and coating with the resin composition is performed while the rotor is being rotated by the rotating shaft. 3. An apparatus for manufacturing a rotor for a small rotating electrical machine, which comprises a rotating shaft, a laminated core fixed on the rotating shaft, and a coil inserted and fixed in a coil insertion groove formed on the outer periphery of the laminated core, further comprising: means for supplying and adhering powder of a resin composition containing tetraglycidyl ether of tetraphenol ethane, a novolac phenol resin, and an inorganic filler to at least a portion of the coil insertion groove of the laminated iron core and the coil end of the coil; An apparatus for manufacturing a rotor for a small rotating electric machine, comprising a thermosetting furnace for curing the resin composition at a temperature of 150° C. or higher. 4. In claim 3, the means for supplying and adhering the powder of the resin composition is by spraying the powder onto the rotor, allowing it to adhere by gravity, or by applying the powder to the outer periphery of the rotor in the resin composition. 1. An apparatus for manufacturing a rotor for a small rotating electrical machine, characterized in that it is equipped with means for submerging the rotor. 5. Claim 4, wherein the resin composition filling/coating means further comprises a rotating means for rotating the rotor by its rotating shaft. Rotor manufacturing equipment. 6. Claim 4 is characterized in that the resin composition filling/coating means further includes means for recovering excess resin composition that has adhered to and fallen onto the rotor. Equipment for manufacturing rotors for small rotating electric machines. 7. A small rotating electric machine according to claim 4, further comprising a preheating furnace for preheating the rotor to 100° C. or higher before filling and coating with the resin composition. Rotor manufacturing equipment.