JP5911312B2 - Manufacturing method of rotor core - Google Patents

Description

The present invention fixes a permanent magnet (including an unmagnetized one) to a laminated core body formed by laminating core pieces with a resin (referred to as “magnet molding method”) rotor core (hereinafter referred to as “magnet molding method”) . The present invention relates to a method of manufacturing a simply “laminated iron core” .

Conventionally, as a method of fixing a permanent magnet to a laminated core body by resin sealing, for example, there is a method described in Patent Document 1. In this method, a plurality of magnet insertion holes (or magnet accommodation holes) are provided in the radially outer region of the rotor laminated core body, and permanent magnets are inserted into the magnet insertion holes and sandwiched between the lower mold and the upper mold. The resin was filled into the magnet insertion hole from the resin pot provided in the upper mold, and the permanent magnet was fixed.

However, in the technique described in Patent Document 1, since the magnet insertion hole is rectangular in a plan view and the periphery is sealed, there is no fear that the resin leaks to the side. Since there is much leakage of the magnetic flux generated by the permanent magnet, as described in Patent Document 2, a part of the magnet insertion hole is opened to reduce the leakage of the magnetic flux of the permanent magnet. Yes.

JP 2007-215301 A WO2011 / 077513

And in the method of patent document 2, as shown to FIG. 5 (A), the part which connected and opened the space parts (hollow space) 60 and 61, ie, the opening parts 62 and 63 on one side. After the permanent magnets 66 and 67 are inserted into the magnet insertion holes 64 and 65, the resin molds 68 and 69 are disposed in the space portions 60 and 61 so as to close the openings 62 and 63, and FIG. As shown in FIG.

However, when the resin molds 68 and 69 are arranged in the space portions 60 and 61, there is a stacking error in the manufacturing process of the laminated iron core, and there is a slight deformation or dimensional error in the space portions 60 and 61 due to the plate thickness deviation of the iron core material. When this occurs, the resin molds 68 and 69 come into contact with the periphery of the space portions 60 and 61 to deform the space portions 60 and 61 and at the same time damage the resin molds 68 and 69, and in some cases, the resin molds 68 and 69. There is a possibility that a gap is formed between the space portions 60 and 61, the resin leakage spreads, and the fixing strength of the permanent magnets 66 and 67 cannot be secured. Here, 70 and 71 are resins that have entered the gaps between the resin molds 68 and 69 and the space portions 60 and 61, and 72 is a laminated iron core.

The present invention has been made in view of such circumstances, and even if a dimensional error occurs in the shape of the space including the opening due to deformation or thickness deviation of the core material caused by pressing of the rotor core, the resin is It aims at providing the manufacturing method of the rotor core which does not leak to the space part which leads to a magnet insertion hole.

A method of manufacturing a rotor core according to the present invention that meets the above-described object is provided by laminating a plurality of core pieces and providing a plurality of magnet insertion holes provided along the circumferential direction, and one of the magnet insertion holes. And manufacturing a rotor core body having a space communicating with the opening through the opening, and then placing a permanent magnet in the magnet insertion hole and a resin mold in the space, respectively. In the manufacturing method of the rotor core for stopping,
State wherein the resin type, wherein the lid portion and the lid portion for closing the opening and an elastic pressing part for pressing the opening and closing the opening in the lid portion which is pressed by the elastic pressing portion Then, the permanent magnet is sealed with resin.

In the method for manufacturing a rotor core according to the present invention, the plurality of magnet insertion holes are each paired, and the opening is disposed to face the space, and the opening of the magnet insertion hole to be the pair Can be closed by the resin mold having the elastic pressing portion in the middle portion and the lid portions on both sides.
Here, the space portion includes not only a space portion (inner space portion) closed in a plan view but also a space partially opened to the outside.

In the method for manufacturing a rotor core according to the present invention, the lid portion is provided on one of the elastic pressing portions, and a pedestal portion that contacts a part of the space portion is provided on the other of the elastic pressing portions. You can also.

In the method for manufacturing a rotor core according to the present invention, the elastic pressing portion is preferably a plate spring bent in a zigzag shape in plan view, but is otherwise bent in a bow shape in plan view. In some cases, it may be a corner bend.

In the method for manufacturing a rotor core according to the present invention, it is preferable that the bent portion of the leaf spring has an arc shape in plan view. In this case, it is preferable that an arc angle of the bent portion having an arc shape is 180 degrees or more and 300 degrees or less.

And in the manufacturing method of the rotor core which concerns on this invention, it is preferable that the said resin type | mold is integrally formed with the hard metal material containing carbon steel or alloy steel (for example, alloy tool steel).

The method for manufacturing a rotor core according to the present invention has the following effects.
(1) Even when a dimensional error occurs in the shape of the space including the opening due to the deformation during pressing of the rotor core or the thickness deviation of the core material, the resin lid is elastic against the opening. Therefore, there is no gap between the opening and the lid that closes the opening, and the resin hardly leaks into the space.
(2) When the resin mold is inserted into the space portion, the elastic pressing portion is deformed or stretched, so that the resin mold is not forcibly inserted into the space portion, and the periphery of the opening portion is not deformed. Thereby, resin leakage can be suppressed.

It is a perspective view of the laminated core main body to which the manufacturing method of the rotor core which concerns on the 1st Embodiment of this invention is applied. It is a partial top view of the arrow a part in FIG. (A), (B) is explanatory drawing of the manufacturing method of the rotor core which concerns on the 2nd Embodiment of this invention. (A), (B) is explanatory drawing of the manufacturing method of the same rotor core, respectively. (A), (B) is explanatory drawing of the manufacturing method of the laminated core which concerns on a prior art example, respectively.

Next, embodiments of the present invention will be described with reference to the accompanying drawings.
As shown in FIG. 1, in the method for manufacturing a rotor core according to the first embodiment of the present invention, core pieces 10 are sequentially punched from a thin sheet material having magnetism by press working, and are caulked and laminated in a mold. Thus, a laminated core (rotor core) main body 11 is formed.

As shown in FIGS. 1 and 2, the laminated core body 11 includes a plurality of pairs of magnet insertion holes 13 and 14 along the circumferential direction, and these magnets are inserted in the center of the pair of magnet insertion holes 13 and 14. A space 17 is provided on one side of the insertion holes 13 and 14 through the openings 15 and 16. Incidentally, the open mouth 15, 16 are arranged to face around the void 17. Further, the space 17 reduces the weight of the laminated core body 11 and improves the magnetic characteristics of the laminated core itself by blocking the magnetic paths of the permanent magnets 19 and 20 inserted in the magnet insertion holes 13 and 14. Therefore, it is preferable to provide a space portion on the other side of the magnet insertion holes 13 and 14.

The space 17 is formed in a rectangular shape with rounded corners in plan view, and has openings 15 and 16 continuous with the magnet insertion holes 13 and 14 at the center of both sides. In the space portion 17, a resin mold 24 including lid portions 21 and 22 provided on both sides and an elastic pressing portion 23 that connects the lid portions 21 and 22 is disposed. Resins (thermosetting resin or thermoplastic resin) flowing from the openings 15 and 16 to the space 17 by the inclined portions of the lids 21 and 22 being pressed against the openings 15 and 16 by the elastic pressing portions 23, respectively. Prevents leakage. At this time, the tips of the lid portions 21 and 22 are located slightly in the magnet insertion holes 13 and 14 from the openings 15 and 16.

In this embodiment, the elastic pressing portion 23 has a leaf spring shape that is bent in a zigzag shape. However, the elastic pressing portion 23 can be expanded and contracted to a hard metal material (for example, carbon steel, alloy tool steel, high-speed steel) or the like. Giving an elastic force. The lid portions 21 and 22 and the elastic pressing portion 23 are integrated. The resin mold 24 has the same cross-sectional shape in the vertical direction, and the space portion 17 and the openings 15 and 16 have the same cross-sectional shape in the vertical direction. Can be plugged in. The height of the resin mold 24 is the same as or slightly smaller than the laminated core body 11. Moreover, the distance of the cover parts 21 and 22 of the resin mold 24 with respect to the width of the opening parts 15 and 16 facing each other in the free state is the distance when the cover parts 21 and 22 are in contact with the opening parts 15 and 16. About 1.05 to 1.2 times the length.

Therefore, in the method of manufacturing the rotor core according to the first embodiment, the resin mold 24 is inserted into each space portion 17 of the laminated core body 11. As a result, the openings 15 and 16 are closed by the lids 21 and 22. Then, the permanent magnets 19 and 20 are inserted into the magnet insertion holes 3 and 14. In this state, the laminated core body 11 is pressurized with the upper mold and the lower mold, and resin is injected into the magnet insertion holes 13 and 14 from the resin pots provided in the upper mold or the lower mold to perform resin sealing.

After the injected resin is cured, the resin mold 24 is pushed out or pulled out using a separately prepared jig. As a result, the space 17 becomes empty, and it is possible to form a rotor core that is lightweight and has good magnetic properties.

Then, the manufacturing method of the rotor core which concerns on the 2nd Embodiment of this invention is demonstrated, referring FIG. 3 (A), (B), FIG. 4 (A), (B).
This rotor core manufacturing method is a further improvement of the conventional manufacturing method of the laminated core shown in FIG. 5. The laminated core body 26 is provided with a pair of magnet insertion holes 27, 28, one of which is provided. Space portions 31 and 32 are provided on the sides through openings 29 and 30, respectively.

A resin mold 33 is provided in each of the space portions 31 and 32. The resin mold 33 includes a lid 35 having a trapezoidal shape in plan view, which closes the openings 29 and 30, an elastic pressing portion 36 having one end fixed to the outer center of the lid 35, and an elastic pressing portion 36. And the pedestal portion 37 fixed to the other end of the flat plate, and the flat cross section has the same shape in the vertical direction.

The elastic pressing portion 36 is made of a plate spring bent in a zigzag shape. The bent portions 39 and 40 of the plate spring are arcuate in plan view, and the arc angles of the bent portions 39 and 40 are 180 degrees or more and 300 degrees. It is as follows (the same applies to the first embodiment). The shape of the pedestal portion 37 is in accordance with the shape of the corners of the space portions 31 and 32, and the pedestal portion 37 is in contact with the corner portions of the space portions 31 and 32 (FIG. 3B, FIG. A) and (B)).

Therefore, in this method of manufacturing the rotor core, the permanent magnets 42 and 43 are placed in the magnet insertion holes 27 and 28, respectively, and the resin mold 33 is placed in the spaces 31 and 32. Thus, the opening 29, 30 provided on one side of the magnet insertion holes 27, 28 is closed by the lid 35, and the inclined portion of the trapezoidal side surface of the lid 35 is the opening 29, 30. At this time, the tip of the lid 35 is positioned slightly entering the magnet insertion holes 27 and 28 from the openings 29 and 30.

Thereafter, the magnet insertion holes 27 and 28 are sealed by the upper mold and the lower mold and filled with resin. The resin sealing method is well known in, for example, Japanese Patent No. 4429258 and the like, and thus will be omitted (the same applies to the above embodiments). When the resin mold 33 is taken out after the filled resin is cured, this portion becomes a space.

The present invention is not limited to the above-described embodiment, and the configuration thereof can be changed without changing the gist of the present invention. For example, in the above-described embodiment, the space portion is sealed in a plan view, but a part thereof may be open to the outside or another space portion.
Moreover, in the said embodiment, although the elastic press part was made into the leaf | plate spring shape, a coil shape may be sufficient, and it has elasticity to a metal (for example, aluminum alloy, magnesium alloy) with small specific gravity depending on the case. It may be buried in the space.

10: Iron core piece, 11: Laminated core body, 13, 14: Magnet insertion hole, 15, 16: Opening part, 17: Space part, 19, 20: Permanent magnet, 21, 22: Cover part, 23: Elastic pressing part 24: Resin mold, 26: Laminated core body, 27, 28: Magnet insertion hole, 29, 30: Opening part, 31, 32: Space part, 33: Resin mold, 35: Lid part, 36: Elastic pressing part, 37: Pedestal part, 39, 40: Bent part, 42, 43: Permanent magnet

Claims (5)

Rotation provided with a plurality of magnet insertion holes formed along a circumferential direction formed by laminating a plurality of iron core pieces, and a space portion communicating with a part of the magnet insertion holes via an opening. after producing the child core body, by placing a resin-type, respectively a permanent magnet in the magnet insertion hole in the space, in the manufacturing method of rotor core that performs resin sealing of the permanent magnet,
State wherein the resin type, wherein the lid portion and the lid portion for closing the opening and an elastic pressing part for pressing the opening and closing the opening in the lid portion which is pressed by the elastic pressing portion And manufacturing the rotor core, wherein the permanent magnet is sealed with resin. 2. The method of manufacturing a rotor core according to claim 1, wherein the plurality of magnet insertion holes are paired, and the opening is disposed to face the space portion, and the opening of the pair of magnet insertion holes is formed. A method of manufacturing a rotor core, comprising: closing the portion with the resin mold having the elastic pressing portion at an intermediate portion and the lid portions on both sides. 2. The method of manufacturing a rotor core according to claim 1, wherein the lid portion is provided on one of the elastic pressing portions, and a pedestal portion that contacts a part of the space portion is provided on the other of the elastic pressing portions. A method for manufacturing a rotor core, characterized by comprising: The method of manufacturing a rotor core according to any one of claims 1 to 3, wherein the elastic pressing unit, manufacturing of the rotor core, characterized in that it consists of a leaf spring that is bent in plan view in a zigzag manner Method. The method of manufacturing a rotor core according to claim 4, the bent portions of the plate spring manufacturing method of the rotor core, characterized in that has an arc shape in plan view.

Images