JP2000166190A - Manufacturing device of rotor of permanent magnet motor and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To take out a rotor core from a mold easily while the deformation of the rotor core in an opening direction is avoided. SOLUTION: A core housing part 14 in which a rotor core 2 is housed is formed in a core holding mold 13 so as to have a diameter a little larger than the outer diameter of the rotor core 2. A casting mold 21 which is coupled with the core holding mold 13 is used for casting permanent magnet molding raw material into the magnet molding raw material filling hole 3 of the rotor core 2. Ejector pins 18 are movably provided in the core holding mold 13 so as to be able to push out the rotor core 2. The ejector pins 18 have holding parts 18c by which the outer surface of the rotor core 2 housed in the core housing part 14 is held so as to be separated from the inner surface of the core housing part 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a permanent magnet formed by filling a permanent magnet molding material obtained by mixing a magnetic powder into a resin melt into a magnet molding material filling hole formed in a cylindrical rotor core. TECHNICAL FIELD The present invention relates to a permanent magnet type rotor manufacturing apparatus and a permanent magnet type motor manufacturing method for forming a permanent magnet type rotor.

[0002]

FIG. 11 shows the structure of a permanent magnet type rotor 1 of this kind of permanent magnet type motor after manufacture, and FIG. 12 shows the structure of the rotor core 2. As shown in FIG.
The rotor core 2 is configured by laminating a number of iron core plates. The rotor core 2 has a cylindrical shape as a whole, and is formed with four substantially arc-shaped holes 3 for filling a magnet forming material which are open in the axial direction. Further, a shaft insertion hole 2a for inserting the rotation shaft 1a is formed in the center of the rotor core 2.

The hole 3 for filling the magnet forming material is filled with a so-called bond magnet 4. This bonded magnet 4
Is obtained by filling and solidifying a permanent magnet molding material in which, for example, a neodymium-based magnetic powder is mixed into a resin melt of a nylon resin, for example, and magnetized. When the permanent magnet molding material is filled, the manufacturing apparatus 5 shown in FIGS. 13 to 15 is used.

That is, the core holding die 6 has the rotor core 2
Circular core arrangement portion 6a having an inner diameter substantially the same as the outer diameter of the core
Are formed, and ejector pins 7 are movably mounted at four positions, and the ejector pins 7 are moved by an ejector plate 7a. Injection mold 8
Are formed with a runner 8a, a gate 8b and a sprue 8c.

[0005] When the bonded magnet 4 is filled,
With the core holding mold 6 and the injection mold 8 separated from each other, the rotor core 2 is arranged in the core arrangement section 6a, and after the molds are matched, the permanent magnet molding material is filled from the injection mold 8 into the magnet molding material filling hole of the rotor core 2. Inject into the part 3 while applying pressure. After the injection is completed, the mold is solidified, the mold is opened, and the ejector plate 7a is moved in the direction of arrow A to move the ejector pins 7, thereby releasing the rotor core 2 (FIG. 15).
reference). Thereafter, the solidified permanent magnet molding material is magnetized to form the bond magnet 4.

When the permanent magnet molding material is pressurized and filled into the magnet molding material filling hole 3, the force F is applied so that the pressure causes the magnet molding material filling hole 3 to expand outward.
(See FIG. 16). In this case, since the rotor core 2 is arranged with almost no gap from the core arrangement portion 6a,
Although the rotor core 2 is not deformed, the outer peripheral surface of the rotor core 2 comes into pressure contact with the core disposition portion 6a. For this reason, the rotor core 2 is
When extruding, there is a problem that the sliding resistance on the inner peripheral surface of the core disposing portion 6a is considerably large and it is difficult to take out. Also,
There is also a problem that the outer peripheral surface of the rotor core 2 is scratched.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to prevent a rotor core from being deformed in a direction in which the rotor core expands and to easily perform the operation when removing the rotor core from the mold. An object of the present invention is to provide an apparatus for manufacturing a rotor of a motor, and to provide a method of manufacturing a permanent magnet type motor having no scratch on the outer peripheral surface of a rotor core.

[0008]

According to a first aspect of the present invention, there is provided a rotor manufacturing apparatus for a permanent magnet type motor, wherein magnetic powder is mixed into a resin melt in a magnet forming material filling hole formed in a cylindrical rotor core. In a permanent magnet rotor manufacturing apparatus in which a permanent magnet molding material is filled and solidified to form a permanent magnet rotor, a circular concave core arrangement portion for disposing the rotor core is slightly larger in diameter than the outer diameter of the rotor core. A core holding mold formed as described above, an injection mold for being molded with the core holding mold and for injecting the permanent magnet molding material into the magnet molding material filling hole of the rotor core, and the rotor core in the core holding mold. It is provided movably so that it can be extruded,
And an ejector pin having a holding portion for holding the outer surface of the rotor core accommodated in the core disposing portion away from the inner peripheral surface of the core disposing portion, and holding the rotor core on the core disposing portion of the core holding type by the ejector pin. The injection mold was matched with the core holding mold, and the permanent magnet molding material was injected and filled into the magnet molding material filling hole of the rotor core from the injection mold, and the permanent magnet molding material was solidified. Then, the rotor core is pushed out from the core arrangement portion by the ejector pin.

In this configuration, there is a predetermined gap between the inner peripheral surface of the core disposition portion and the outer peripheral surface of the rotor core, and the ejector pins hold the outer peripheral surface of the rotor core. The ejector pins can prevent the rotor core from being expanded and deformed even when the rotor core is subjected to an outward expanding deformation force when the hole is filled with the permanent magnet molding material, and when the rotor core is removed from the mold, the outer periphery of the rotor core is removed. The surface does not come into sliding contact with the inner peripheral surface of the core disposition portion, so that the rotor core can be easily taken out while preventing deformation of the rotor core in the expanding direction.

According to a second aspect of the present invention, there is provided a rotor manufacturing apparatus for a permanent magnet type motor, wherein a plurality of ejector pins are provided, and each of the ejector pins is formed so that the outside thereof is tapered with respect to the pushing direction. It is characterized in that the rotor core is moved in parallel with the pushing direction to push the rotor core. In this configuration, when the ejector pin is moved, the tapered portion of the ejector pin can be satisfactorily separated from the core holding type, and the rotor core can be more easily taken out.

According to a third aspect of the present invention, there is provided a rotor manufacturing apparatus for a permanent magnet type motor, wherein a plurality of ejector pins are provided, and the ejector pins are mutually expanded in a process of moving in an extrusion direction. In this configuration, when the ejector pin is moved, the ejector pin moves in the expanding direction, so that the ejector pin and the rotor core are automatically separated from each other, and the removal of the rotor core from the ejector pin is facilitated. .

According to a fourth aspect of the present invention, there is provided a method of manufacturing a permanent magnet type motor having a cylindrical shape having a hole for charging a magnet forming material so as to be held by a plurality of ejector pins provided in a circular concave core arrangement portion. Inserting and disposing a rotor core of, and injecting and solidifying a permanent magnet molding material into the magnet molding material filling hole, and moving the ejector pins to remove the rotor core from the core disposition portion in a non-contact state, It is characterized in that it comprises a step of magnetizing the injected and solidified permanent magnet molding material and a step of incorporating the rotor core into a stator.

According to this manufacturing method, since the ejector pin holds the rotor core, when the permanent magnet molding material is injected and filled into the magnet molding material filling hole of the rotor core, the rotor core expands outward. Even if a deforming force is applied, the expansion deformation can be prevented by the ejector pins, and when the rotor core is removed from the mold in a non-contact state by the ejector pins, the outer peripheral surface of the rotor core is in sliding contact with the inner peripheral surface of the core disposition portion. Without having
In addition to making it easier to take out the rotor core, it is possible to manufacture a permanent magnet type motor having no scratches on the outer peripheral surface of the rotor core.

According to a fifth aspect of the present invention, there is provided a method of manufacturing a permanent magnet motor, wherein the ejector pins are formed in a tapered shape with respect to the direction in which the rotor core is taken out, and move in parallel with the direction in which the rotor core is taken out. Have.
In this manufacturing method, when the ejector pin is moved, the tapered portion of the ejector pin can be satisfactorily separated from the core arrangement portion, so that the rotor core can be more easily taken out and the outer peripheral surface of the rotor core can be easily removed. A permanent magnet type motor without scratches can be manufactured.

According to a sixth aspect of the present invention, there is provided a method of manufacturing a permanent magnet type motor, wherein ejector pins are mutually expanded in a process of moving in a direction in which a rotor core is taken out. In this manufacturing method, when the ejector pin is moved, the ejector pin moves in the expanding direction.
The ejector pins and the rotor core are automatically separated from each other, so that the rotor core can be easily taken out from the ejector pins, and a permanent magnet motor having no scratch on the outer peripheral surface of the rotor core can be manufactured.

[0016]

FIG. 1 to FIG. 8 show a first embodiment of the present invention (corresponding to claims 1, 3 and 4).
This will be described with reference to FIG. FIG. 1 shows a permanent magnet type rotor manufacturing apparatus 11 in a matched state. The movable holding plate 12 is provided with a core holding mold 13 via a spacer portion 12a.
The core holding die 13 is formed with a core concave portion 14 having a circular concave shape that opens on the right side surface, as shown in FIGS. 2 and 3. The core arrangement portion 14 is set to have an inner diameter slightly larger than the outer diameter of the rotor core 2, and a cylindrical portion 14 a protrudes from the center of the bottom of the core arrangement portion 14.

Further, the core holding die 13 is formed with a pin guide portion 15 which is arranged at an equal circumference 4 with respect to the center of the core arrangement portion 14. The pin guide portions 15 are inclined so as to expand mutually with respect to the core pushing direction (the direction is indicated by an arrow A, which is a direction along the axis of the core disposition portion 14). In this case, each pin guide portion 15
Has a rectangular cross section in the core holding mold 13, a part of which extends from the bottom of the core disposition portion 14 to the inner peripheral surface thereof, as shown in FIG. Has made.

An ejector plate 16 is provided on the movable mounting plate 12 between the spacer portions 12a so as to be movable in the direction of the arrow A and in the opposite direction via an ejector rod 7. This ejector plate 16 has four ejector pins 18 via pin holders 17.
The ejector pins 18 are inserted into the pin guides 15. The above pin holder 17
Is movable in the centrifugal direction (direction of arrow B) and in the opposite direction. The ejector plate 16 is moved by an actuator (not shown).
Now, when the ejector pin 18 is moved in the direction of arrow A from the state of FIG. 1, the ejector pin 18 is guided by the pin guide portion 15 and moves as a whole in the direction of arrow A, but moves so as to expand mutually. Things.

This ejector pin 18 is shown in FIGS.
As shown in the figure, an L-shaped holding portion 18c formed of a surface portion 18a perpendicular to the extrusion direction (the direction of arrow A) and a surface portion 18b parallel to the direction is formed inside the front end portion. In the state shown in FIG. 1, the surface portion 18a is flush with the bottom surface 14b of the core placement portion 14, and the surface portion 18b protrudes toward the center from the inner peripheral surface 14c. The surface portion 18b is formed in the shape of an arc having substantially the same curvature as the curvature of the outer peripheral surface of the rotor core 2. The distance between the opposed surface portions 18b is determined by the diameter of the outer peripheral surface of the rotor core 2 (outer diameter dimension). ) Is almost the same.

On the other hand, four guide bars 20 (only two are shown in FIG. 1) extend to the left from the fixed-side mounting plate 19, and the injection bar 21 can move the guide bars 20. Mounted on The injection mold 21 is composed of divided plates 22 and 23, and one of the divided plates 22 is formed with a runner 22a and has four gates 22.
b (only two shown) are formed in a uniform arrangement form.
The other split plate 23 has a fitting portion 23a into which the sprue body 24 having the sprue 24a is fitted. The sprue body 24 is mounted on a fixed-side mounting plate 19, and a locating ring 25 is mounted on the fixed-side mounting plate 19. An opening of an injection molding machine (not shown) is connected to the locate ring 25. The gate 22b of the split plate 22 faces the hole 3 for filling the magnet forming material of the rotor core 2.

Now, a description will be given of a case where the magnet molding material filling hole 3 of the rotor core 2 is filled with the permanent magnet molding material and solidified in the above-described configuration. As shown in FIG.
The rotor core 2 is inserted and arranged in the core arrangement portion 14 of the core holding mold 13. In this case, the holding portion 1 of each ejector pin 18
The rotor core 2 is held by the ejector pins 18 by fitting the outer peripheral surface of the rotor core 2 to 8c. Accordingly, a gap G (see FIGS. 7 and 8) exists between the rotor core 2 and the inner peripheral surface 14c of the core disposition portion 14. Also,
In this case, the hole 3 for filling each magnet molding material is inserted into the gate 22b.
To face.

Then, after performing mold matching as shown in FIG.
A permanent magnet molding material (indicated by reference numeral 26 in FIG. 5) is injected from an injection molding machine (not shown), and a hole for filling the magnet molding material of the rotor core 2 in the core arrangement portion 14 through the sprue 24a, the runner 22a and the gate 22b. Pressure injection into the part 3. At this time, the rotor core 2 receives a force F (see FIG. 8) by the pressure so that the hole 3 for filling the magnet forming material expands outward. In this case, since the rotor core 2 is held from the outside by the ejector pins 18, the rotor core 2 is not deformed.

After the injection is completed, the mixture is solidified, the mold is opened, and the ejector plate 16 is moved in the direction indicated by the arrow A.
5 to move the ejector pin 18 as shown in FIG. In this case, the ejector pins 18 are guided by the pin guide portion 15 and generally move in the direction of arrow A, but move so as to expand each other. Thereby, the rotor core 2 is extruded from the core disposition portion 14. In this case, the rotor core 2 is
4 does not come into sliding contact with the inner peripheral surface 14c. Then, the surface portion 18 b of the ejector pin 18 also naturally separates from the outer peripheral surface of the rotor core 2. The dividing plates 22 and 23 of the injection mold 21 are also divided as shown in FIG.

Thereafter, the solidified kneaded material is magnetized to form the bond magnet 4. Then, as shown in FIG. 11, the rotating shaft 1 is provided in the hollow portion 2a of the rotor core 2.
The rotor 1 is manufactured by inserting and fixing a, and a permanent magnet motor is manufactured by incorporating the rotor 1 into a stator (not shown).

According to such an embodiment, the core placement unit 1
4, there is a predetermined gap G between the inner peripheral surface 14c of the rotor core 2 and the outer peripheral surface of the rotor core 2, and the ejector pins 18 hold the outer peripheral surface of the rotor core 2. When the permanent magnet molding material is injected and filled into the rotor core 3, even if an outward expanding deformation force acts on the rotor core 2, the expanding deformation can be prevented by the ejector pins 18. When taking out, the outer peripheral surface of the rotor core 2 is
Therefore, the rotor core 2 can be easily taken out without sliding contact with the rotor core 4c. Further, the outer peripheral surface of the rotor core 2 is not scratched.

In particular, since the ejector pins 18 are configured to expand in the process of moving in the extrusion direction A, the ejector pins 18 and the rotor core 2 automatically separate from each other, and the rotor core 2 can be easily taken out.

FIGS. 9 and 10 show a second embodiment of the present invention. In this embodiment, the configurations of the ejector pins 31 and the pin guide portions 32 are slightly different. That is, the ejector pins 31 are integrally fixed to the ejector plate 16, and the ejector pins 31 are formed so that the inner surface side is parallel to the extrusion direction A, and the outer surface side is sequentially outward with respect to the extrusion direction A. It is formed in a deviating taper shape. The guide portion 32 is also formed so that its inner surface side is parallel to the extrusion direction A, and its outer surface side is formed in a tapered shape that is sequentially biased outward with respect to the extrusion direction A.

In the above configuration, the ejector plate 1
When 6 is moved in the direction of arrow A, as shown in FIG.
The tapered portion on the outer side of the ejector pin 18 is well separated from the tapered portion of the pin guide portion 32 of the core holding die 13, and the ejector pin 18 and the core holding die 1
The mold core 3 can be easily separated from the mold, and the rotor core 2 can be more easily taken out.

[0029]

As is apparent from the above description, the present invention can be easily performed when removing the rotor core from the mold while preventing the rotor core from being deformed in the expanding direction, and also has a scratch on the outer peripheral surface of the rotor core. It has an excellent effect of not sticking.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a manufacturing apparatus in a mold matching state according to a first embodiment of the present invention.

FIG. 2 is a front view of a core holding type.

FIG. 3 is a perspective view of a core holding type.

FIG. 4 is a perspective view of a core holding type having different operation states of ejector pins.

FIG. 5 is a longitudinal sectional side view of the manufacturing apparatus in a mold open state.

FIG. 6 is a perspective view of a core holding type with an ejector pin removed.

FIG. 7 is a vertical cross-sectional side view of the manufacturing apparatus, which is sectioned at a portion other than the ejector pins.

FIG. 8 is a front view of a core holding type in which a rotor core is arranged.

FIG. 9 is a view corresponding to FIG. 1, showing a second embodiment of the present invention.

FIG. 10 is a diagram corresponding to FIG. 5;

FIG. 11 is a perspective view of a permanent magnet type rotor.

FIG. 12 is a perspective view of a rotor core.

FIG. 13 is a diagram corresponding to FIG. 1 showing a conventional example.

FIG. 14 is a diagram corresponding to FIG. 2;

FIG. 15 is a diagram corresponding to FIG. 5;

FIG. 16 is a diagram corresponding to FIG. 8;

[Explanation of symbols]

2 is a rotor core, 3 is a hole for filling a permanent magnet molding material, 1
1 is a manufacturing apparatus, 13 is a core holding type, 14 is a core arrangement portion,
15 is a pin guide portion, 18 is an ejector pin, 18c is a holding portion, 21 is an injection mold, 26 is a permanent magnet molding material, 31
Indicates an ejector pin, and 32 indicates a pin guide portion.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor: Manabu Okamura 33, Shinisogo-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture F-term in Toshiba Institute of Industrial Science (Reference) 5H622 CA02 CA05 CA10 CA13 CB04 CB05 DD02 DD04 DD05 PP03 PP20 QA03

Claims (6)

[Claims] 1. A permanent magnet type in which a permanent magnet forming material obtained by mixing magnetic powder into a resin melt is filled into a hole for filling a magnet forming material formed in a cylindrical rotor core and solidified to form a permanent magnet type rotor. In a rotor manufacturing apparatus for a motor, a core holding mold in which a circular concave core arrangement section for arranging the rotor core is formed to have a diameter slightly larger than an outer diameter of the rotor core; An injection mold for injecting the permanent magnet molding material into the magnet molding material filling hole, and a rotor core movably provided so that the rotor core can be pushed out of the core holding mold, and housed in the core disposing portion. An ejector pin having a holding portion for holding an outer surface of the core away from the inner peripheral surface of the core disposition portion, wherein the ejector rotor is mounted on the core holding portion of the core holding type The injection mold is matched with the core holding mold, and the permanent magnet molding material is injected and filled from the injection mold into the magnet molding material filling hole of the rotor core. And a rotor core for a permanent magnet type motor, wherein a rotor core is extruded from a core arrangement portion by the ejector pin after solidification. 2. A plurality of ejector pins are provided, each ejector pin is tapered on the outside with respect to the pushing direction, and each ejector pin moves in parallel with the pushing direction to push the rotor core. 2. The permanent magnet type motor rotor manufacturing apparatus according to claim 1, wherein: 3. The apparatus for manufacturing a rotor of a permanent magnet type motor according to claim 1, wherein a plurality of ejector pins are provided, and the ejector pins are mutually expanded while moving in the pushing direction. 4. A step of inserting and arranging a cylindrical rotor core having a hole for filling a magnet forming material so as to be held by a plurality of ejector pins provided in a core arrangement portion having a circular concave shape; A step of injecting and solidifying a permanent magnet molding material into a filling hole; a step of moving the ejector pins to remove a rotor core from the core disposition portion in a non-contact state; and a step of magnetizing the injected and solidified permanent magnet molding material. And a step of incorporating the rotor core into a stator. 5. The permanent magnet motor according to claim 4, wherein the ejector pins are formed in a tapered shape with respect to a direction in which the rotor core is taken out, and move in parallel with the direction in which the rotor core is taken out. Production method. 6. The method for manufacturing a permanent magnet motor according to claim 4, wherein the ejector pins are mutually expanded in a process of moving in a direction in which the rotor core is taken out.