JP2013138532A - Multilayer iron core - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multilayer iron core which suppresses fractures of coupling parts and, even if a fracture occurs, prevents the fracture part from affecting the external shape of the multilayer iron core.SOLUTION: A plurality of segment iron core pieces 12 connected via coupling parts 11 as a belt are spirally wound and stacked to form a multilayer iron core. The coupling parts 11 are shaped like arcs of concentric circles as a whole, and an external shape line 15 of the coupling parts 11 is located radially inside of an external shape line 16 of the segment iron core pieces 12. In addition, coupling parts 11 of the segment iron core pieces 12 neighboring in the stacking direction are stacked to have different locations in the circumferential direction.

Description

The present invention relates to a laminated core in which a plurality of segment core pieces continuous in a strip shape are spirally wound and laminated.

In the production of a laminated core, when an annular core piece is punched out from a metal strip, a lot of scraps are generated, resulting in a problem that the material yield is lowered. As a countermeasure, there is known a method of manufacturing a laminated core by punching and forming a plurality of segment core pieces continuous in a strip shape from a metal strip, and winding and spiraling them.

In the manufacturing method, a plurality of arc-shaped segment core pieces are punched from a metal strip into a shape extending linearly via a connecting portion formed on the outer peripheral side, and a plurality of continuous segments are bent while the connecting portion is bent. An iron core piece is spirally wound and laminated (for example, Patent Document 1).

JP 2010-193715 A

However, when the plurality of segment core pieces are spirally wound and arranged in an annular shape, the shape of the connecting portion is narrow in an allowable range so that the connecting portion can be easily bent. When the connecting portion is bent, the stress is locally concentrated, and the connecting portion may be broken. The broken part protrudes from the outer shape of the laminated iron core, resulting in a reduction in motor performance and workability in the assembly process. Also, since the connecting part bulges in the plate thickness direction by bending, if the connecting parts of segment core pieces adjacent in the stacking direction overlap when winding, the thickness of the stacked core will vary, which will affect the quality of the motor. Adversely affect.

The present invention has been made in view of such circumstances, and suppresses breakage of the connecting portion, does not affect the outer shape of the laminated core even when the breakage occurs, and suppresses variation in the thickness of the laminated core. It aims at providing a laminated iron core.

The invention of claim 1 that meets the above-mentioned object is a laminated iron core in which a plurality of segment iron core pieces that are connected in a strip shape via a connecting portion are spirally wound and laminated.
The shape of the connecting portion is a concentric circular arc as a whole, and the outer shape line of the connecting portion is disposed radially inward from the outer shape line of the segment core piece.
Furthermore, in the invention of claim 2, the positions of the connecting portions of the segment core pieces adjacent in the stacking direction are shifted and stacked in the circumferential direction.

In the laminated iron core according to claim 1, since the entire shape of the connecting portion is a concentric circular arc shape, there is no portion where stress is locally concentrated. Thereby, it can suppress that a connection part fractures | ruptures. Further, since the outer shape line of the connecting portion is located radially inward from the outer shape line of the segment core piece, it is possible to prevent the broken portion from protruding from the outer shape of the laminated core even when the connecting portion is broken.

Since the laminated iron core according to claim 2 is laminated by shifting the positions of the connecting portions of the segment core pieces adjacent to each other in the laminating direction in the circumferential direction, the connecting portions do not overlap in the laminating direction. It can suppress that dispersion | variation generate | occur | produces in the thickness of a laminated iron core by the bulging part which arises by bending a part.

It is a top view of the rotor lamination | stacking iron core which concerns on one embodiment of this invention. It is a partial top view of the strip-shaped segment core piece connected by the connection part in the same rotor lamination | stacking iron core. It is detail drawing of the connection part of the segment core piece in the same rotor lamination | stacking iron core. It is a top view of the stator lamination | stacking iron core which concerns on one embodiment of this invention. It is a partial top view of the strip-shaped segment core pieces connected by the connection part in the same stator laminated core. It is detail drawing of the connection part of the segment core piece in the stator lamination | stacking iron core.

Subsequently, the form of the present invention will be described with reference to the drawings for understanding of the present invention.
As shown in FIG. 1 and FIG. 2, the laminated core according to the embodiment of the present invention has a plurality of segment core pieces 12 connected in a strip shape via a connecting portion 11 formed on the outer peripheral portion. 11 is a rotor laminated core 10 in which a plurality of continuous segment core pieces 12 are spirally wound and laminated while bending 11. A total of 22 poles, that is, 22 permanent magnet holding portions 13 are provided on the outer periphery, and one segment core piece 12 has four permanent magnet holding portions 13. A permanent magnet is fixed to the permanent magnet holding portion 13 with an adhesive or the like. Since the number of permanent magnet holding portions 13 of the entire laminated core is not a multiple of the number of permanent magnet holding portions 13 of one segment core piece 12, the connecting portions 11 of the segment core pieces 13 adjacent in the stacking direction when wound are There is no overlap in the circumferential direction. This will be described in detail below.

The rotor laminated core 10 is formed by punching a plurality of segment core pieces 12 connected in a strip shape from a magnetic steel sheet having a thickness of, for example, about 0.5 mm or less through a connecting portion 11 with a die, and is continuously punched. It is comprised by winding and laminating. Here, as a method for laminating the plurality of segment core pieces 12, any one of caulking, welding, and adhesion can be applied, or any two or more can be used in combination. In the present embodiment, the layers are stacked by caulking by caulking 14.

Between the adjacent segment core pieces 12, the connection part 11 which couple | bonds the segment core pieces 12 with an outer peripheral part is provided. As shown in FIG. 3, projecting portions 19 projecting outward in the radial direction to be the permanent magnet holding portion 13 after being bent are formed at both ends of the connecting portion 11, and the tips of the projecting portions 19 become flat. Yes. The width of the connecting portion 11 in the radial direction before being bent is formed narrow. The connecting portion 11 has a concentric circular arc shape as a whole, and its center 18 is set radially outward. By using the concentric circular arc shape, the stress generated in the connecting portion 11 during bending is not concentrated locally, but the entire connecting portion 11 is dispersed, whereby the breaking of the connecting portion 11 can be suppressed.

The radial width of the connecting portion 11 is set to 1 to 3 times the plate thickness of the segment core piece 12, and if it falls below this range, the rigidity of the connecting portion 11 is reduced, and breakage occurs at the time of conveyance or before bending. It becomes easy. Moreover, if it exceeds this range, the rigidity of the connection part 11 will become high too much and it will become difficult to bend.

A concave notch 17 is provided on the radially outer side of the connecting portion 11. The concave notch 17 prevents the portion protruding radially outward (radially bulging portion) from protruding from the outer shape of the laminated core when the connecting portion 11 is bent and the segment core pieces 12 are annularly arranged. Moreover, the outer shape line 15 of the connecting portion 11 is set radially inward from the outer shape line 16 of the segment core piece 12, specifically, the imaginary line L extending linearly from the flat portion at the tip of the protruding portion 13. Thereby, even when a rupture occurs in the connecting portion 11 during bending, the rupture portion is prevented from projecting from the outer shape of the laminated core and affecting the outer shape of the laminated core.

In the present embodiment, since the number of permanent magnet holding portions 13 of the entire laminated core is not a multiple of the number of permanent magnet holding portions 13 of one segment core piece 12, one strip-shaped plate (that is, the connecting portion 11). Even when the laminated cores are manufactured by spirally winding the segment core pieces 12) connected in a strip shape, the connecting portions 11 of the segment core pieces 13 adjacent to each other in the stacking direction do not overlap in the circumferential direction. It is also possible to manufacture a laminated iron core by winding a plurality of strips (for example, two strips) in a spiral shape, and productivity can be improved by increasing the lamination speed.

In the present embodiment, the structure having a permanent magnet on the radially outer surface of the rotor laminated core has been described as an example. However, the present invention is also applied to a structure having a permanent magnet inside the rotor laminated core. can do.

In addition, similar to the above embodiment, the present invention can be applied to a stator laminated core. As shown in FIGS. 4 and 5, the stator laminated iron core 20 having a shape in which the tooth portion 24 protrudes radially inward from the annularly arranged yoke portion 23 is connected via a connecting portion 21 formed on the outer peripheral portion. A plurality of segment core pieces 22 that are continuous in a band shape are wound and laminated in a spiral manner while bending the connecting portion 21. In the present embodiment, the layers are laminated by caulking and bonding by caulking 25, but any one of caulking, welding, and adhesion can be applied, or any two or more can be used in combination.

As shown in FIG. 6, the connecting portion 21 has a concentric circular arc shape as a whole, and its center is set on the outer side in the radial direction. The outer shape line of the connecting portion 21 is set radially inward from the outer shape line of the segment core piece 22. The connecting portion 21 has a concentric circular arc shape as a whole, and its center 29 is set radially outward. By using the concentric circular arc shape, the stress generated in the connecting portion 21 at the time of bending is not concentrated locally, but the entire connecting portion 21 is dispersed, whereby the breakage of the connecting portion 21 can be suppressed.

A concave notch 26 is provided on the radially outer side of the connecting portion 21. When the connecting portion 21 is bent and the segment core pieces 22 are arranged in an annular shape, the concave notch 26 prevents the portion protruding radially outward (radially bulging portion) from protruding from the outer shape of the laminated core. Moreover, the outer shape line 27 of the connecting portion 21 is set radially inward from the outer shape line 28 of the segment core piece 22, specifically, the virtual line M extending linearly from the outer shape of the segment core piece 22. Thereby, even when a rupture occurs in the connecting portion 21 at the time of bending, the rupture portion is prevented from projecting from the outer shape of the laminated core and affecting the outer shape of the laminated core.

In the present embodiment, since the number of teeth 24 of the entire laminated core is a multiple of the number of teeth 24 per one segment core piece 22, one strip-shaped plate (that is, a band at the connecting portion 21). When the laminated segment cores 22) are spirally wound to produce a laminated core, the connecting portions of the segment core pieces 22 adjacent in the laminating direction overlap. However, by producing a laminated core by spirally winding a plurality of strips (for example, two strips), it is possible to avoid variations in the thickness of the laminated core.

In the embodiment presented in the present invention, a laminated core is manufactured by spirally winding a single strip or a plurality of strips. However, the segment core pieces 12 and 22 connected in a strip form are stacked. It is also possible to cut into a length corresponding to one layer, wind and laminate one layer at a time.

The present invention is not limited to the above-described embodiments, and includes other embodiments and modifications that can be considered within the scope of the matters described in the claims.

10: Rotor laminated core, 11: connecting portion, 12: segment core piece, 13: permanent magnet holding portion, 14: caulking, 15: outer shape line of connecting portion, 16: outer shape line of segment core piece, 17: concave cut Notch, 18: Center of concentric circle, 19: Protruding part, 20: Stator laminated core, 21: Connection part, 22: Segment core piece, 23: Yoke part, 24: Teeth part, 25: Caulking, 26: Concave notch 27: Outline line of connecting part, 28: Outline line of segment core piece, 29: Concentric circle center, L, M: Virtual line

Claims (2)

In a laminated iron core in which a plurality of segment iron core pieces connected in a strip shape via a connecting portion are spirally wound and laminated,
The connecting portion has a concentric circular arc shape as a whole, and an outer shape line of the connecting portion is disposed radially inward from an outer shape line of the segment core piece. 2. The laminated core according to claim 1, wherein the positions of the connecting portions of the segment core pieces adjacent to each other in the lamination direction are shifted in the circumferential direction.

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