JP2014050114A - Manufacturing method of laminated core and, laminated core manufactured using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated core in which reduction of material yield is prevented, shape precision of the laminated core is improved and a width of a magnetic pole axial piece is changed.SOLUTION: A manufacturing method of a laminated core in which a plurality of arcuate segment core pieces are die-cut from a bar, the segment core pieces are laminated in an annular shape, and a width is gradually reduced in upper and lower portions of a magnetic pole axial part, includes: a slot die-cutting step of die-cutting and forming slots with different widths. The slot die-cutting step includes the steps of: forming a middle layer portion of the magnetic pole axial part; forming an upper layer portion and a lower layer portion of the magnetic pole axial part; and forming a top layer portion and a bottom layer portion of the magnetic pole axial part.

Description

The present invention relates to a method for manufacturing a laminated core in which a plurality of arc-shaped segment core pieces are laminated in an annular shape, and a laminated core produced using the same.

Recently, for the purpose of improving the space factor of the laminated core in the magnetic pole shaft portion, as shown in FIGS. 4A and 4B, the magnetic pole shaft portion 91 of the divided laminated core 90 is viewed from the cross section aa. The width of 92 and the lower part 93 is gradually reduced. According to this, the winding around the magnetic pole shaft portion 91 can be wound without causing a gap between the upper end portion 92 and the lower end portion 93 of the magnetic pole shaft portion 91.

The above-described divided laminated core 90 is manufactured by stamping with a progressive die as shown in FIG. 5 (Patent Document 1). In step 2, the first mold 96 moves along one radial inner side of the yoke piece 94, and in step 3, the second mold 97 moves along the other radial inner side of the yoke piece 94. The width of the magnetic pole piece piece 95 can be adjusted. The first and second molds 96 and 97 are slowly retracted or advanced with respect to the press working reference line, thereby forming the divided laminated core 90 in which the width of the magnetic pole piece 95 is changed.

Further, the laminated iron core whose width of the magnetic pole piece is changed can be formed by punching with a progressive die as shown in FIG. 6 (Patent Document 2). In step 3, the first mold 98 and the second mold 99 in step 5 can be rotated to the left and right with respect to the central axis of the core piece 100. The first and second molds 98 and 99 rotate to the left and right with respect to the central axis of the iron core piece 100 to form a laminated iron core in which the width of the magnetic pole piece piece 101 is changed.

JP2008-67588 JP2008-061315

In the manufacturing method of the split laminated iron core of Patent Document 1, it is necessary to assemble the split laminated iron cores in an annular shape after winding around the magnetic pole shaft portion 91 of the split laminated core. Here, since the divided laminated cores are individually formed, a slight difference occurs in the accuracy of each divided laminated core due to deviations in sheet thickness, etc., making it difficult for the connecting portions of the divided laminated cores to be fitted together. There was a problem that took time. In addition, in the method for manufacturing a laminated iron core disclosed in Patent Document 2, the mold becomes larger than the mold used in Patent Document 1. For this reason, the press machine which attaches a metal mold | die also became large, and the installation expense of a metal mold | die and a press machine was expensive. Further, although the shape accuracy of the laminated iron core is higher than that of the divided laminated iron core, the material yield is lowered. As described above, both of the manufacturing methods of Patent Document 1 and Patent Document 2 have problems.

An object of the present invention is to provide a laminated core in which the shape accuracy of the laminated core is improved without reducing the material yield, and the width of the pole piece is changed.

The method for manufacturing a laminated core according to the first aspect of the invention is to punch a plurality of on-arc segment core pieces from a strip, to stack the segment core pieces in an annular shape, and to make the width of the upper part and the lower part of the magnetic pole shaft part larger. In the manufacturing method of the gradually reduced laminated iron core, it has a slotting step of punching and forming slots having different widths, and the slotting step includes a step of forming a middle layer portion of the magnetic pole shaft portion, an upper layer portion of the magnetic pole shaft portion, and It is performed by a step of forming a lower layer portion and a step of forming the uppermost layer portion and the lowermost layer portion of the magnetic pole shaft portion.

In the laminated core manufacturing method according to the first aspect of the present invention, in the punched region of the segment core piece formed in the slot punching step, the punched piece portion forming the magnetic pole shaft piece portion of the segment core piece is The slot is formed by repeatedly punching in the circumferential direction of the segment core pieces.

In the method for manufacturing a laminated core according to the first invention, the punched piece portion has an outer contour portion and an inner contour portion, and the outer contour portion forms an outer peripheral contour of the segment core piece, the inner contour. The part forms the inner peripheral contour of the segment core piece and the contour of the magnetic pole piece.

The laminated core according to the second aspect of the invention that meets the object is a laminated core manufactured by the method for manufacturing a laminated core according to the first aspect, wherein a segment core piece is interposed between the adjacent segment core pieces. A connecting portion is provided for coupling in the outer peripheral region.

A laminated core in which the shape accuracy of the laminated core is improved and the width of the magnetic pole piece is changed can be manufactured without reducing the material yield.

It is possible to reduce the size of the die and the press machine to which the die is attached, and furthermore, since high thrust is not required for the press machine, the equipment cost of the die and the press machine can be reduced.

The step of forming the inner contour of the segment core piece and the step of forming the outer contour can be performed simultaneously, the number of manufacturing steps can be reduced, and productivity can be improved.

(A) is a top view of the laminated core manufactured with the manufacturing method of the laminated core which concerns on one embodiment of this invention, (B) is sectional drawing of the magnetic pole axial part which looked at (A) from the aa direction. It is explanatory drawing of the manufacturing method of the laminated core which concerns on one embodiment of this invention. It is explanatory drawing of the manufacturing method of the laminated core which concerns on other embodiment of this invention. (A) is a top view of the division | segmentation laminated | stacked iron core which concerns on a prior art example, (B) is sectional drawing of the magnetic pole axial part which looked at (A) from the aa direction. It is explanatory drawing of the manufacturing method of the division | segmentation laminated | stacked iron core which concerns on a prior art example. It is explanatory drawing of the manufacturing method of the laminated core which concerns on a prior art example.

Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.
First, the laminated core manufactured using the manufacturing method of the laminated core which concerns on one embodiment of this invention is demonstrated.
The laminated iron core 10 is a stator laminated iron core (stator). As shown in FIG. 1A, the laminated iron core 10 has a plurality of thicknesses, for example, from electromagnetic steel sheets (an example of strips) having a thickness of about 0.15 to 0.5 mm. The arc-shaped segment core pieces 11 are punched out and the segment core pieces 11 are laminated in a ring shape. Here, any one of caulking, welding, and adhesion can be applied to the method of laminating the plurality of segment core pieces 11, or any two or more can be used in combination.

The laminated core 10 has an arcuate yoke portion 12 and a plurality of magnetic pole shaft portions 13 formed inside thereof, and a plurality of slots 14 are provided between the magnetic pole shaft portions 13.
Moreover, between the adjacent segment core pieces 11, the connection part 15 which couple | bonds the segment core pieces 11 in an outer peripheral area | region is provided, and while being helically wound and laminated | stacked, it is fixed by the caulking part 16. FIG.

Here, FIG. 1B shows a cross section of the magnetic pole shaft portion 13 as viewed from the aa direction in FIG. 1A. The width of the upper layer portion and the lower layer portion of the magnetic pole shaft piece portion 17 is narrow in the stacking direction. Thus, the upper and lower corner portions 18 of the magnetic pole shaft portion 13 are inclined and rounded. When the magnetic pole shaft portion 13 is formed in this way, the winding can be smoothly applied to the magnetic pole shaft portion 13, the winding length can be saved for the same number of windings, and the winding to the magnetic pole shaft portion 13 can be saved. The space factor of the line can be improved. Moreover, damage to the insulating coating of the winding can be prevented.

Then, the manufacturing method of the laminated iron core which concerns on one embodiment of this invention is demonstrated, referring FIG.
First, a preparation process for forming the pilot hole 20 will be described.
The pilot holes 20 are formed at a predetermined pitch in the feeding direction on both sides in the width direction of the electromagnetic steel sheet 21 while conveying the electromagnetic steel sheet 21. 2 indicate the positions where the pilot holes 20 are formed.

Next, the slot extraction process for performing slot extraction will be described.
The slot extraction process includes three processes with different extraction widths. In the formation of the middle layer portion of the magnetic pole piece 17, the first slot 22 is punched with a cutter having the narrowest slot width in the slotting step.
The upper layer portion and the lower layer portion of the magnetic pole piece 17 are formed by punching the second slot 23 with a blade whose slot width is wider than that of the first slot 22 in the slot extracting step. In the formation of the uppermost layer and the lowermost layer of the magnetic pole piece piece 17, the third slot 24 is punched with a blade having the widest slot width in the slotting process.

At the time of punching, the segment core piece 11 forms the laminated core 10 by winding lamination. Therefore, only the blade for punching the third slot 24 in the slotting process is moved to the first layer from the bottom of the winding lamination to move the magnetic pole piece 15 The lowermost layer portion is formed, and the lower layer portion of the magnetic pole piece 15 is formed by moving only the blade for punching the second slot 23 in the slotting process to the second layer from the bottom of the winding stack. Only the blade that punches the first slot 22 in the slot punching process after the layer is moved to form the middle layer portion of the magnetic pole piece 15. Thereafter, only the blade for punching the second slot 23 in the slot removing process is moved to the second layer from the winding stack to form the upper layer portion of the magnetic pole piece 15, and the slot removing process is performed to the first layer from the winding stack. Only the blade that punches out the third slot 24 is moved to form the uppermost layer portion of the magnetic pole piece 15.

Next, in order to form the connecting portion 15, the space between the adjacent segment core pieces 11 is punched out. Then, the laminated core 10 having the magnetic pole shaft portion 13 in which the width of the magnetic pole shaft piece portion 15 is increased or decreased is formed by sequentially performing the caulking portion forming step, the inner shape portion removing step, and the outer shape portion removing step, and winding and laminating. .

Then, the manufacturing method of the laminated iron core which concerns on other embodiment of this invention is demonstrated, referring FIG.
First, a preparation process for forming the pilot hole 25 will be described. The pilot holes 25 are formed at a predetermined pitch in the feeding direction on both sides in the width direction of the electromagnetic steel sheet 26 using the pilot hole forming mold 27 while conveying the electromagnetic steel sheet 26. 3 indicates the formation position of the pilot hole 25 by the pilot hole forming mold 27. The pilot hole forming mold 27 is a pair of two pilot holes 25 arranged on both sides of the electromagnetic steel plate 26 in the width direction. In this way, the pilot hole forming mold 27 can be downsized because the width in the feeding direction of the electromagnetic steel sheet 26 only needs to be wide enough to form one pilot hole 25.

Next, a description will be given of a slotting / contour forming process in which slotting, inner shape portion punching, and outer shape portion punching are performed using the circumferential contour forming die 28.
In the punching region 30 of the electromagnetic steel plate 26 in which one segment core piece 29 is punched (the region surrounded by the pilot holes 25 adjacent in the feeding direction of the electromagnetic steel plate 26), punching is performed to form the segment core piece 29. A plurality of (here, five) first punched piece portions 33 having the same shape and having the outer contour portion 31 and the inner contour portion 32 exist in the circumferential direction of the segment core piece 29. The outer contour portion 31 is an elongated shape and is a part for forming the outer peripheral contour of the yoke piece portion 34 of the segment core piece 29 to be formed. Further, the inner contour portion 32 is an inverted T-shape and is a part for forming the inner peripheral contour of the yoke piece portion 34 and the contour of the magnetic pole shaft piece portion 35 of the segment core piece 29 to be formed.

For this reason, a metal mold having a shape corresponding to the first punched piece portion 33, that is, a circumferential contour forming mold 28 is used, and the electromagnetic steel sheet 26 is repeated a plurality of times (here, in the circumferential direction of the segment core piece 29). (5 times) 3 indicates the position of the first punched piece portion 33 that is first punched by the circumferential contour forming die 28.
The first punched piece portion 33 means a portion punched by the circumferential contour forming die 28, and therefore does not exist in the electromagnetic steel sheet 26 after being punched by the circumferential contour forming die 28. For convenience, it is indicated by a two-dot chain line as necessary (hereinafter the same).

When punching, it is necessary to move the circumferential contour forming mold 28 in the circumferential direction of the segment core pieces 29. As this method, the circumferential contour forming mold 28 may be rotated by a predetermined angle around the center of curvature of the segment core piece 29. For example, a method described in JP-A-2007-89326 is disclosed. Etc. can be used.
Here, for punching, a circumferential contour forming die 28 in which one slot 36 is formed by one punching is used, but depending on the size of the segment core piece 29 to be formed, etc., the punching is performed once. A circumferential contour forming mold that can form a plurality of (two or three) slots may be used. In this case, according to the circumferential punching width of the inner contour portion, the circumferential punching width of the outer contour portion is also adjusted.
The punching by the circumferential contour forming die 28 may be performed so that the circumferential end of the punching position is continuous, but it is preferable to perform the punching while overlapping the circumferential end of the punching position.

Thus, by repeating the above method (here, 5 times), the outer peripheral contour of the yoke piece portion 34 of the segment core piece 29 to be formed, the inner peripheral contour of the yoke piece portion 34 and the magnetic pole shaft piece portion 35 Each contour can be formed.
The punching by the circumferential contour forming mold 28 is sequentially performed from the end, but is not limited to this, and may be performed from the central portion in the circumferential direction (hereinafter the same). .

Here, the slot extraction / contour formation process includes three processes with different extraction widths. The width of the inner diameter contour portion 32 of the first punched piece portion 33 becomes wider as it advances in the feeding direction of the electromagnetic steel sheet 21. In the formation of the middle layer portion of the magnetic pole piece, the first punch piece 33 is punched with a blade whose inner contour portion 32 has the smallest width in the slot punching / contour forming step. The upper layer portion and the lower layer portion of the magnetic pole piece are formed with a cutter whose inner contour portion is wider than the inner contour portion 32 of the first punched piece portion 33 in the slotting / contour forming step. 2 punching piece 37 is punched out. In the formation of the uppermost layer and the lowermost layer of the magnetic pole piece, the third punched piece 38 is punched with a blade whose inner contour is widest in the slot punching / contour forming step. At this time, the width of the outer contour portion 31 in each step is the same.

At the time of punching, since the segment core pieces 29 form a laminated core by winding lamination, only the cutter of the circumferential direction contour forming die 41 for punching the third punching piece portion 38 in the first layer from the bottom of the winding lamination is moved to make the magnetic poles. The lowermost layer portion of the magnetic pole shaft piece portion is moved by moving only the cutter of the circumferential contour forming mold 40 that forms the lowermost layer portion of the shaft piece portion and punches the second punched piece portion 37 in the second layer from the bottom of the winding stack. The middle layer portion of the magnetic pole shaft piece portion is formed by moving only the blade of the circumferential contour forming mold 28 for punching the first punched piece portion 33 after the third layer from the bottom of the winding stack. Thereafter, the upper layer portion of the pole shaft piece portion is formed by moving only the blade of the circumferential contour forming die 40 for punching the second punched piece portion 37 in the second layer from the winding layer, and one layer from the winding layer. Only the blade of the circumferential contour forming die 41 that punches the third punch piece 38 is moved to form the uppermost layer portion of the magnetic pole piece.

Next, a caulking portion forming process for forming the caulking portion using the caulking portion forming mold 42 will be described with reference to FIG.
The caulking portion forming mold 42 is formed as a pair of two caulking portions 43 that are disposed in proximity to the segment core pieces 29 adjacent to each other in the feeding direction of the electromagnetic steel sheet 26. The hatched portion in the caulking portion forming step in FIG. 3 indicates the formation position of the caulking portion 43 by the caulking portion forming mold 42. Since one caulking portion 43 to be formed on one segment core piece 29 is formed on each side in the circumferential direction of the segment core piece 29, one side of the adjacent segment core pieces 29 is larger than the distance between the caulking portions 43. The distance between the caulking portions 43 disposed on the other side is shorter. For this reason, the size of the caulking portion forming mold 42 can be reduced.
The caulking portion forming step may be included in the slot punching / contour forming step without being provided separately from the slot punching / contour forming step. At this time, the caulking portion may be formed by a circumferential contour forming mold, and a mold for forming the caulking portion is provided separately from the circumferential contour forming die. It may be rotated and formed one by one.

And the connection part formation process which forms the connection part 45 using the side part outline formation metal mold | die 44 is demonstrated, referring FIG.
Between the segment core pieces 29 adjacent to each other in the feeding direction of the electromagnetic steel sheet 26, there is a contour portion 46 that forms the segment core pieces 29. The contour 46 is continuous with the punching position of the outer contour of the adjacent segment core pieces 29, and the outer piece 47 that forms the outer peripheral end contour of each segment core piece 29, and the inner side of the adjacent segment core pieces 29. It has the inner piece part 48 which forms the side part outline of each segment iron core piece 29 continuously with the punching position of a contour part. A connecting portion 45 is formed between the outer piece portion 47 and the inner piece portion 48.

For this reason, a die having a shape corresponding to the contour 46, that is, a side contour forming die 44 is used, and the contour 46 is punched to form the segment core pieces 29. 3 indicates the position of the contour 46 to be punched out by the side contour forming mold 44. In FIG.
Here, the side contour forming die 44 has a blade having a shape corresponding to the outer piece 47 and a blade having a shape corresponding to the inner piece 48, and a gap is provided between the blades. The connecting portion 45 is formed.

A plurality of continuous segment core pieces 29 formed as described above are spirally wound and laminated while being bent at the connecting portion 45 to produce a laminated core. At this time, it is preferable that the inside of the segment core piece 29 is wound around a cylindrical body having a predetermined diameter and wound in a spiral shape.
From the above, by using the method for manufacturing a laminated core according to the present invention, the laminated core is formed without reducing the material yield, improving the shape accuracy of the laminated core, and changing the width of the pole piece. Is done.

As described above, the present invention has been described with reference to the embodiment. However, the present invention is not limited to the configuration described in the above embodiment, and the matters described in the scope of claims. Other embodiments and modifications conceivable within the scope are also included. For example, the magnetic pole shaft pieces of the uppermost layer and the lowermost layer are not limited to one, and two or more magnetic pole shaft pieces having different widths may be stacked. Similarly, the magnetic pole shaft pieces of the upper layer portion and the lower layer portion are not limited to one, and two or more magnetic pole shaft pieces having different widths may be stacked. As a result, the corner portion of the magnetic pole shaft portion is more rounded, so that the winding can be smoothly applied to the magnetic pole shaft portion, and the winding length can be saved for the same winding to the magnetic pole shaft portion. The space factor of the windings can be improved.

10: laminated iron core, 11: segment core piece, 12: yoke portion, 13: magnetic pole shaft portion, 14: slot, 15: connecting portion, 16: caulking portion, 17: magnetic pole shaft piece portion, 18: corner portion, 20: Pilot hole, 21: electromagnetic steel plate, 22: first slot, 23: second slot, 24: third slot, 25: pilot hole, 26: electromagnetic steel plate, 27: mold for forming pilot hole, 28: Die for circumferential contour formation, 29: segment core piece, 30: punched region, 31: outer contour, 32: inner contour, 33: first punched piece, 34: yoke piece, 35: pole axis One part, 36: slot, 37: second punched piece part, 38: third punched piece part, 40: mold for circumferential contour forming, 41: mold for circumferential contour forming, 42: caulking part forming Mold, 43: Caulking part, 44: Side contour Mold: 45: connecting part, 46: contour part, 47: outer piece part, 48: inner piece part, 90: divided laminated iron core, 91: magnetic pole shaft part, 92: upper part, 93: lower part, 94: yoke One piece, 95: magnetic pole piece, 96: first die, 97: second die, 98: first die, 99: second die, 100: iron core piece, 101: magnetic pole Shaft piece

Claims (4)

In a manufacturing method of a laminated core in which a plurality of segment core pieces on a circular arc are punched from a strip, the segment core pieces are laminated in an annular shape, and the widths of the upper and lower portions of the magnetic pole shaft portion are gradually reduced, slots having different widths are punched A slotting step, the slotting step comprising: forming a middle layer portion of the magnetic pole shaft portion; forming an upper layer portion and a lower layer portion of the magnetic pole shaft portion; and an uppermost layer portion of the magnetic pole shaft portion; A method for producing a laminated iron core, which is performed by a step of forming a lowermost layer portion. 2. The method of manufacturing a laminated core according to claim 1, wherein a punched piece portion forming a magnetic pole shaft piece portion of the segment core piece is provided in the punched region of the segment core piece formed in the slotting step. A method of manufacturing a laminated core, wherein the slot is formed by repeatedly punching in a circumferential direction of the core piece. 3. The method of manufacturing a laminated core according to claim 2, wherein the punched piece portion has an outer contour portion and an inner contour portion, and the outer contour portion forms an outer peripheral contour of the segment core piece, and the inner contour portion. Is a method of manufacturing a laminated core, characterized in that the inner peripheral contour of the segment core piece and the contour of the magnetic pole piece are formed. It is a laminated core manufactured with the manufacturing method of the laminated core of Claims 1-3, Comprising: Between the said adjacent segment core pieces, the connection part which couple | bonds a segment core piece in an outer peripheral area | region is provided. Characteristic laminated iron core.

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