JP2003061273A - Stacked iron core and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stacked iron core which can enhance the motor efficiency by easily preventing the conduction between thin-plate-shaped magnetic members, thereby suppressing the eddy current loss. SOLUTION: In a stacked iron core 2 which is made by stacking thin-plate- shaped magnetic members 1 and where a plurality of magnetic pole teeth are projected at specified intervals, the vicinity of the tip of the projection 1a of each thin-plate-shaped magnetic member 1 forming each magnetic pole tooth is pressed to be thinner than other section so as to make each thin part 1b, and the specified positions in their middles are bound together by drawing calking.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated iron core formed by laminating thin plate-shaped magnetic members, and more particularly to a structure for preventing the generation of eddy currents at the tips of magnetic pole teeth.

[0002]

2. Description of the Related Art Generally, a rotary electric motor uses a laminated iron core formed by stacking thin plate-shaped magnetic members in order to reduce iron loss. Since the stator and the rotor of the rotary motor are magnetically uneven, they have harmonic components other than the fundamental wave. This harmonic component fluctuates at a high frequency of about several hundreds to several thousands Hz or more and induces an eddy current loss, particularly near the gap between the stator and the rotor, that is, at the tip of the magnetic pole teeth.

However, since the thin plate-shaped magnetic members forming the laminated iron core are formed by press working, burrs are generated on the tip surfaces of the magnetic pole teeth, and conduction is caused between the stacked thin plate-shaped magnetic members. The eddy current loss is further increased, which causes a reduction in motor efficiency. For this reason, these burrs must be removed by shot blasting, that is, burr removal must be performed. However, the burr removal for each thin plate-shaped magnetic member significantly lowers the productivity. Therefore, for example, Japanese Patent Laid-Open No. 8-
Japanese Patent No. 340659 discloses that productivity is improved by performing burr removal by press working.

[0004]

As described above, in the conventional laminated iron core, the productivity is improved by performing the burr removal by pressing, but it is necessary to add a pressing step for the burr removal. Of course, the actual wear of the press die changes every moment depending on the conditions such as the material used.Therefore, high precision control is required in the press process in order to bail off the end face of the thin plate magnetic member. There was a problem that was done. Further, there is a problem that it is difficult to reliably prevent conduction between the thin plate magnetic members because the end faces are close to each other even if the burr is completely removed.

The present invention has been made to solve the above problems, and can easily prevent conduction between thin plate magnetic members to suppress eddy current loss and improve motor efficiency. It is an object of the present invention to provide a possible laminated iron core and a manufacturing method thereof.

[0006]

A laminated iron core according to claim 1 of the present invention is a laminated iron core formed by laminating thin plate-shaped magnetic members and having a plurality of magnetic pole teeth at predetermined intervals. Each of the thin plate-shaped magnetic members forming the teeth is thinly formed by pressing in the vicinity of the tip of the protrusion.

The laminated core according to claim 2 of the present invention is the laminated core according to claim 1, wherein the thin portion of the projection of each thin plate-shaped magnetic member is bent at a predetermined angle in the axial direction of the laminated core. It was made.

The laminated core according to claim 3 of the present invention is the laminated core according to claim 2, in which magnetic pole teeth bent on different sides are mixed.

A laminated core according to a fourth aspect of the present invention is the laminated core according to the second or third aspect, in which the tip of the thinly formed portion is chamfered at a predetermined angle.

According to a fifth aspect of the present invention, in the laminated iron core according to any one of the second to fourth aspects, the thickness t of the thinly formed portion is T, and the thickness of the thin plate-shaped magnetic member is T. When the angle is δ, it is set to a value that satisfies the expression Tcosδ>t> 0.8Tcosδ.

According to a sixth aspect of the present invention, in the method for manufacturing a laminated core according to the first aspect, the thin plate-shaped magnetic members are pressed to form a predetermined shape and are sequentially stacked. The step of forming and the step of bending the tip side of each magnetic pole teeth at the same time in the axial direction of the laminated iron core by inserting a bending jig having a predetermined diameter into the tip side of the magnetic pole teeth is included. It is a thing.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. Embodiment 1. 1 is a front view showing a structure of a laminated iron core according to Embodiment 1 of the present invention, FIG. 2 shows a structure of a main part of the laminated iron core in FIG. 1, (A) is a front view, and (B) is FIG. FIG. 3A is a cross-sectional view showing a cross-section taken along line BB shown in FIG. 3A), and FIG. 3 is a plan view showing a step of forming the thin plate-shaped magnetic member of the laminated iron core in FIG. 1 by press punching.

In the figure, reference numeral 1 is a thin plate-shaped magnetic member formed in an annular shape, and a plurality of protrusions 1a are provided at predetermined intervals inside.
2B, a thin portion 1b having a thickness t smaller than the thickness T of the other portion is formed near the tip of each of the protrusions 1a, and a predetermined portion in the middle of the thin portion 1b. Concave and convex portions 1c and 1d for punching and caulking are respectively formed at the positions. Reference numeral 2 denotes a laminated iron core formed by stacking a predetermined number of thin plate-shaped magnetic members 1 and fitting the recesses and protrusions 1c and 1d of each thin plate-shaped magnetic member 1 and then by uncoupling them. A plurality of magnetic pole teeth 2a are formed by the protrusions 1a of each thin plate-shaped magnetic member 1.

Next, a manufacturing process of the laminated core in the first embodiment having the above-mentioned structure will be described with reference to the drawings. First, at a position indicated by an arrow A in FIG. 3, as a first step of processing the thin plate-shaped magnetic member 1, a portion shown by hatching in the drawing is punched. Next, at the position indicated by the arrow B, the region shown by hatching in the drawing is punched out to process the region b for forming the thin portion 1b. Next, at a position indicated by an arrow C, a portion indicated by hatching in the drawing, that is, a region b is pressed to be processed into a thickness t smaller than the thickness T of other portions.

Next, at the position indicated by the arrow D, the portion indicated by hatching in the drawing is press punched to form the protrusion 1a. Then, at the position indicated by the arrow E, the hole 1e of the thin plate-shaped magnetic member 1 located on the leftmost side of the paper surface in FIG.
Recesses and convex portions 1c and 1d of the other thin plate-shaped magnetic member 1 are formed respectively, and finally, at the position indicated by arrow G, the thin plate-shaped magnetic member 1 is formed by punching out the hatched portion in the drawing. Then, the laminated cores 2 are completed by sequentially stacking them in the mold, fitting the concave portions and the convex portions 1c, 1d of the respective thin plate-shaped magnetic members 1, and punching and caulking them into one body.

As described above, according to the first embodiment, the vicinity of the tip of the protrusion 1a of each thin plate-shaped magnetic member 1 forming each magnetic pole tooth 2a is thinly processed by pressing to form the thin portion 1b. Therefore, there is always a gap in the vicinity of the tip of the protrusion 1a of each thin plate-shaped magnetic member 1, that is, between the thin portions 1b, and the end faces do not come into contact with each other. Since conduction between the magnetic members 1 is prevented, eddy current loss can be suppressed and motor efficiency can be improved.

Embodiment 2. 4A and 4B show a structure of a main part of a laminated iron core according to a second embodiment of the present invention. FIG. 4A is a front view, and FIG. 4B is a cross section showing a cross section taken along line BB shown in FIG. 4A. 5 and 5 are plan views showing a process of forming the thin plate-shaped magnetic member of the laminated iron core in FIG. 4 by press punching.

In the figure, 11 is a thin plate-shaped magnetic member formed in an annular shape, and a plurality of protrusions 11a are formed so as to protrude inward at predetermined intervals, and the protrusions 11a are formed in the vicinity of the tips thereof. As shown in FIG. 4 (B), the thickness T of other parts
The thin portion 11b having a smaller thickness t has a predetermined angle δ.
Is bent in the laminating direction of the laminated core, which will be described later, and also at a predetermined position on the way, concave and convex portions 11c, 11 for punching and caulking.
d are formed respectively. 12 is a thin plate-shaped magnetic member 1
1 is stacked in a predetermined number, and each concave portion of each thin plate-shaped magnetic member 11,
A laminated iron core integrally formed by fitting the convex portions 11c and 11d together and pulling out the plural magnetic pole teeth 12a by the protrusion portions 11a of the thin plate-shaped magnetic members 11.
Are formed.

Next, the manufacturing process of the laminated core in the second embodiment having the above-mentioned structure will be described with reference to the drawings. First, at a position indicated by an arrow A in FIG. 5, as a first step of processing the thin plate-shaped magnetic member 11, a portion indicated by hatching in the drawing is punched. Next, at the position indicated by the arrow B, the area shown by hatching in the drawing is punched out to process the region b for forming the thin portion 11b. Next, at a position indicated by an arrow C, a portion indicated by hatching in the drawing, that is, a region b is pressed to be processed into a thickness t smaller than the thickness T of other portions.

Next, at the position shown by the arrow D, the portion shown by hatching in the drawing is punched out by press to form the projection 11a. Then, at the position indicated by arrow E, the hole 11e of the thin plate-shaped magnetic member 11 located on the leftmost side of the paper surface in FIG. Concave and convex 11
c and 11d are formed respectively. Next, at a position indicated by an arrow G, a portion indicated by hatching in the drawing, that is, the thin portion 11b is inclined by press working at a predetermined angle δ shown in FIG. 4B, and finally, at a position indicated by an arrow H, The thin plate-shaped magnetic member 11 is formed by punching out the portion indicated by the middle hatching, and the thin plate-shaped magnetic members 11 are sequentially stacked in the mold, and the concave and convex portions 11 of each thin plate-shaped magnetic member 11 are formed.
The c and 11d are fitted and removed and caulked to be integrated to complete the laminated core 12.

As described above, according to the second embodiment, the vicinity of the tip of the protrusion 11a of each thin plate-shaped magnetic member 11 forming each magnetic pole teeth 12a is thinly processed by pressing to form a thin portion 11b. This thin part 1
Since 1b is bent at a predetermined angle δ in the stacking direction, each thin plate-shaped magnetic member 1 is, as indicated by L in FIG. 4B.
Since a space is secured between the end faces of the thin portion 11b of No. 1 and conduction between the stacked thin plate-shaped magnetic members 11 is prevented, eddy current loss can be suppressed and motor efficiency can be improved.

In the above structure, each thin plate-shaped magnetic member 1 is used.
The case where the thin portions 11b of No. 1 are tilted on the same side in the stacking direction by the predetermined angle δ has been described. You can do this, in this case,
Since the electromagnetic forces applied in the axial direction are canceled by each other, it is possible to reduce the weight of the portion that holds the laminated iron core, and thus it is possible to reduce the size of the motor.

Embodiment 3. FIG. 6 is a sectional view showing a manufacturing process of a main part of a laminated iron core according to a third embodiment of the present invention. The laminated core according to the third embodiment has substantially the same configuration as that of the second embodiment, except that the thin-walled portion 21b formed near the tip of the protruding portion 21a of the thin plate-shaped magnetic member 21 has The difference is that chamfering (shown by C in the figure) is performed at a predetermined angle φ, for example, by pressing.

As described above, according to the third embodiment, since the tip of the thin portion 21b is chamfered C at a predetermined angle φ, eddy current can be suppressed as well as shown in FIG. 6 (B). As shown, the chamfer C forms a flat magnetic pole surface facing the rotor (not shown), so that the motor efficiency can be further improved.

Fourth Embodiment FIG. 7 is a sectional view showing a structure of a main part of a laminated iron core according to a fourth embodiment of the present invention. The laminated core according to the fourth embodiment has the same structure as that of the second embodiment, but the thin portion 11
The thickness t of b is set to a value that satisfies the following equation (1), where T is the thickness of the thin plate-shaped magnetic member 11 and δ is the bending angle. Tcosδ>t> 0.8 Tcosδ (1)

As described above, according to the fourth embodiment, the thickness t of the thin portions 11b is set to a value satisfying the above equation (1), so that the thin portions 11b exert unreasonable force on each other. Can be bent in the contacted state without receiving,
It is possible to obtain a stable structure. When the thickness t is greater than Tcosδ, the thin portions 11b receive unreasonable force, making it difficult to bend, and when the thickness t is less than Tcosδ, a gap is generated between the thin portions 11b, and each is unstable. It becomes a composition.

Embodiment 5. FIG. 8 is a sectional view showing a part of the steps of the method for manufacturing a laminated iron core according to the fifth embodiment of the present invention. Hereinafter, a method of manufacturing a laminated core according to the fifth embodiment of the present invention will be described with reference to the drawings including the steps of manufacturing the laminated core according to the first embodiment.

As in the first embodiment, first, at the position shown by the arrow A in FIG. 3, as a first step of processing the thin plate magnetic member 1, the portion shown by hatching in the drawing is punched out. Next, at the position indicated by the arrow B, the region shown by hatching in the drawing is punched out to process the region b for forming the thin portion 1b. Next, at a position indicated by an arrow C, a portion indicated by hatching in the drawing, that is, a region b is pressed to be processed into a thickness t smaller than the thickness T of other portions.

Next, at the position shown by the arrow D, the portion shown by hatching in the drawing is press punched to form the protrusion 1a. Then, at the position indicated by the arrow E, the hole 1e of the thin plate-shaped magnetic member 1 located on the leftmost side of the paper surface in FIG.
The thin plate-shaped magnetic member 1 is formed by forming the concave portions and the convex portions 1c and 1d of the remaining other thin plate-shaped magnetic member 1 respectively, and then punching out the portion indicated by the hatching in the figure at the position indicated by the arrow G. While being sequentially laminated in the mold, the concave and convex portions 1c and 1d of each thin plate-shaped magnetic member 1 are fitted and integrated by punching and caulking, and the same laminated iron core as in the first embodiment. 2 is formed.
Finally, as shown in FIG. 8, a rod-shaped bending jig 31 having a diameter larger than the diameter of the inner periphery is inserted into the inner peripheral side of the laminated iron core 2, and the thin portions 1b are simultaneously folded in the laminating direction. By bending, a laminated core 32 similar to the laminated core 12 in the second embodiment is completed.

As described above, according to the fifth embodiment, the vicinity of the tip of the projection 11a of each thin plate-shaped magnetic member 11 forming each magnetic pole teeth 12a is thinly processed by press working to form a thin portion 11b. This thin part 1
Since 1b is bent at a predetermined angle δ in the stacking direction, it is of course possible to suppress eddy current loss and improve motor efficiency as in the first and second embodiments. That is, since the thin portions 11b are bent at the same time, it is possible to provide a method for manufacturing a laminated core that can improve productivity. In each of the above-described embodiments, the laminated core of the rotary motor has been described as an example, but it is needless to say that the present invention is not limited to this and can be applied to the laminated core of a linear motor or the like.

[0031]

As described above, according to the first aspect of the present invention, in the laminated iron core which is formed by laminating thin plate-shaped magnetic members and has a plurality of magnetic pole teeth at predetermined intervals, each magnetic pole taste is provided. Since the vicinity of the tip of the protrusion of each thin plate-shaped magnetic member forming is formed thin by press working,
It is possible to provide a laminated iron core that can prevent conduction between thin plate-shaped magnetic members, suppress eddy current loss, and improve motor efficiency.

According to a second aspect of the present invention, in the first aspect, the thinly formed portion of the protrusion of each thin plate-shaped magnetic member is bent at a predetermined angle in the axial direction of the laminated iron core. Therefore, it is possible to provide a laminated iron core capable of preventing conduction between thin plate-shaped magnetic members, suppressing eddy current loss, and improving motor efficiency.

According to a third aspect of the present invention, in the second aspect, the magnetic pole teeth bent on different sides are arranged in a mixed manner, so that a laminated core capable of reducing the size of the motor can be obtained. Can be provided.

According to a fourth aspect of the present invention, in the second or third aspect, the tip of the thin portion is chamfered at a predetermined angle, so that the efficiency of the motor can be further improved. A laminated iron core can be provided.

According to claim 5 of the present invention, in any one of claims 2 to 4, the thickness t of the thinly formed portion is T, the thickness of the thin plate-shaped magnetic member is T, and the bending angle is When δ is set, a value satisfying the expression Tcosδ>t> 0.8Tcosδ is set, so that it is possible to provide a laminated iron core that can obtain a stable structure.

According to a sixth aspect of the present invention, a step of forming a laminated iron core according to the first aspect by press-working the thin plate-shaped magnetic members to form a predetermined shape and sequentially stacking By inserting a bending jig having a predetermined diameter at the tip side of the magnetic pole teeth, the tip side of each magnetic pole tooth is bent at the same time in the axial direction of the laminated iron core at a predetermined angle. It is possible to provide a method for manufacturing a laminated core, which can improve productivity as well as improvement.

[Brief description of drawings]

FIG. 1 is a front view showing the structure of a laminated core according to a first embodiment of the present invention.

2 shows the structure of the main part of the laminated core in FIG.
2A is a front view, and FIG. 2B is a cross-sectional view showing a cross section taken along line BB shown in FIG.

FIG. 3 is a plan view showing a step of forming a thin plate-shaped magnetic member of the laminated iron core in FIG. 1 by press punching.

FIG. 4 shows a structure of a main part of a laminated iron core according to a second embodiment of the present invention, (A) is a front view and (B) is FIG.
It is sectional drawing which shows the cross section along the line BB shown to (A).

5 is a plan view showing a step of forming the thin plate-shaped magnetic member of the laminated iron core in FIG. 4 by press punching.

FIG. 6 is a cross-sectional view showing a manufacturing process of a main part of a laminated iron core according to a third embodiment of the present invention.

FIG. 7 is a sectional view showing a structure of a main part of a laminated iron core according to a fourth embodiment of the present invention.

FIG. 8 is a cross sectional view showing a part of the step of the method for manufacturing a laminated iron core according to the fifth embodiment of the present invention.

[Explanation of symbols]

1,11,21 Thin plate-shaped magnetic members 1a, 11a, 21
a Protrusion, 1b, 11b, 21b Thin-walled portion, 1c, 1
1c concave part, 1d, 11d convex part, 1e, 11e hole part, 2, 12, 32 laminated core, 2a, 12a magnetic pole teeth, T, t thickness, δ bending angle, L interval, C
Chamfer, 31 bending jig.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroyuki Akita             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo             Inside Ryo Electric Co., Ltd. (72) Inventor Masaya Inoue             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo             Inside Ryo Electric Co., Ltd. F-term (reference) 5H002 AA02 AB06 AC06 AC08 AE07                 5H615 AA01 BB01 BB14 PP01 PP10                       SS02 SS03 SS05 SS19

Claims (6)

[Claims] 1. A laminated iron core having a plurality of magnetic pole teeth formed at predetermined intervals by laminating thin plate magnetic members, and a tip of a protrusion of each thin plate magnetic member forming each magnetic pole taste. A laminated core characterized in that the vicinity of the part is formed thin by pressing. 2. The laminated core according to claim 1, wherein the thin portion of the protrusion of each thin plate-shaped magnetic member is bent at a predetermined angle in the axial direction of the laminated core. 3. The laminated core according to claim 2, wherein bent magnetic pole teeth are mixedly arranged on different sides. 4. The laminated core according to claim 2, wherein the tip of the thinly formed portion is chamfered by pressing at a predetermined angle. 5. When the thickness t of the thinly formed portion is T and the bending angle is δ, the thickness t of the thin portion is set to a value that satisfies the expression Tcosδ>t> 0.8Tcosδ. It is set, It is characterized by the above-mentioned.
The laminated iron core according to any one of 1 to 4. 6. A step of forming a laminated iron core according to claim 1 by press-forming a thin plate-shaped magnetic member to form a predetermined shape and sequentially stacking it, and having a predetermined diameter on the tip side of the magnetic pole teeth. A method for manufacturing a laminated core, comprising a step of bending the tip ends of the magnetic pole teeth at the same time in the axial direction of the laminated core at a predetermined angle by inserting a bending jig therethrough.