JP2008252978A - Method of manufacturing laminated core - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a laminated core by which strong caulking strength of caulking coupling and excellent shape accuracy characteristics of uprightness and plane parallelism in the laminated core can be obtained. <P>SOLUTION: A caulking projection 10t of an iron core piece 10, in which on one side 10a thereof, the caulking projection 10t is formed and on the other side 10b thereof, a recess 10r or a caulking through-hole 10w penetrating from the one side 10a to the other side 10b is formed, is inserted into the recess 10r or the caulking through-hole 10w of the other iron core piece 10, and the iron pieces 10 are stacked on other iron pieces 10 by caulking. The method of manufacturing the laminated core has a process of forming the caulking projection 10t of the iron core piece 10 in such a manner that the center line Ot passing the plane center of the caulking projection 10t in a plan view is located at the center Oa side of the iron core piece 10 than a center line Or passing the plane center of the recess 10r or the caulking through-hole 10w in the plan view. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a laminated core in which a laminated core is manufactured by punching iron pieces from a metal plate and caulking and laminating these predetermined number of pieces.

  Laminated iron cores, such as stator laminated iron cores and rotor laminated iron cores, are manufactured by caulking and laminating a plurality of core pieces punched from a thin metal plate such as an electromagnetic steel plate.

FIG. 4 is a conceptual cross-sectional view showing a state in which the outer shape of the core piece is punched out from a thin metal plate such as an electromagnetic steel sheet and caulked and laminated in a conventional method of manufacturing a laminated core.
The laminated iron core 51 is manufactured by punching the outer shape of the iron core piece 10 'from the metal thin plate 11 into a predetermined shape by a press mold apparatus, and caulking and laminating the punched iron core piece 10' on another iron core piece 10 '. It is.

In order to manufacture the laminated iron core 51, first, the caulking protrusion 10t ′ is formed in advance on one side surface of the thin metal plate 11. Further, by forming the caulking projection 10t ′ on the other side surface of the thin metal plate 11 before punching, a caulking through hole 10w ′ penetrating from one side surface to the other side surface is formed in advance.
Next, the outer shape of the iron core piece 10 'is punched out from the metal thin plate 11 by a press die device, and the caulking protrusion 10t' of the iron core piece 10 'is formed into the recess 10r' of another iron core piece 10 'or the caulking through hole 10w'. When inserted into and crimped, the core piece 10 'can be crimped to the other core piece 10'.
The manufactured core piece 10 ′ (FIG. 6) of the laminated core 51 has a caulking projection 10 t ′ formed on one side surface 10 a and a recess 10 r ′ or a caulking through hole 10 w ′ formed on the other side surface 10 b. Become a thing.
The press die apparatus includes a punching punch 31 for punching the outer shape of the iron core piece 10 'and an outer punching die 32 for loading and housing the punched iron core piece 10'.

  In this conventional method of manufacturing a laminated core, when the caulking protrusion 10t ′ of the iron core piece 10 ′ is formed as described above, the shape of the caulking protrusion 10t ′ in plan view is the recess 10r ′ or the caulking through hole. The caulking protrusion 10t ′ is formed so as to have the same shape as 10w ′ in plan view. Further, the center line passing through the center of the surface when the caulking projection 10t ′ is viewed in plan matches the center line when the recess 10r ′ or the caulking through hole 10w ′ is viewed in plan.

  The production of the laminated core 51 by the press mold apparatus is performed at a high speed in order to improve productivity, reduce costs, etc. As shown in FIG. 4, the core piece 10 ′ is removed from the thin metal plate 11. In the caulking and laminating step, warpage (hereinafter, this warpage is referred to as “drawing warpage”) usually occurs in the iron core piece 10 ′ which is extracted from the die 32 and extracted.

  When this warpage occurs, when the caulking protrusion 10t ′ is inserted into the recess 10r ′ of another iron core piece 10 ′ already stacked in the die 32, the portion positioned outside the caulking protrusion 10t ′ (the iron core piece 10 ′) is in contact with the other side surface 10b near the recess 10r ′ of the other core piece 10 ′, so that the caulking protrusion 10t ′ of the core piece 10 ′ is in contact with the other core piece 10 ′. The iron core piece 10 'may be deformed because it cannot be inserted into the recess 10r'. Further, due to the deformation of the iron core piece 10 ′, a gap is formed between the layers of the iron core piece 10 ′ of the manufactured laminated iron core 51, thereby reducing the caulking strength, and the uprightness and the plane parallelism in the laminated iron core 51. There was a problem that the accuracy of the shape deteriorated.

  As a measure for solving this problem, for example, as shown in FIG. 5, the caulking projection 10t ″ formed on one side surface 10a of the iron core piece 10 ″ is formed from a convex portion that is circular when viewed in plan. In addition, the flat surface of the recess 10r ″ formed on the other side surface 10b is larger than the circular arc of the circular convex portion, and the straight line on which the circular convex portion is press-fitted at a position inside the circular arc of the circular convex portion. A circular arc that is formed so as to be formed of a portion 14 ″ and is larger than the circular convex portion in the direction in which the core piece 10 ″ is warped when the outer shape of the core piece 10 ″ is punched as shown in FIG. There has been proposed a structure in which the portion 13 ″ is arranged and caulked and joined (see Patent Document 1).

Note that FIG. 5 described above is a conceptual plane showing the shape and positional relationship of caulking protrusions formed on one side surface of a core piece of a laminated core manufactured by a conventional method of manufacturing a laminated core and recesses formed on the other side surface. FIG. FIG. 6 is a conceptual cross-sectional view of the iron core piece of FIG.
The line Ot ″ in FIGS. 5 and 6 is a center line passing through the center of the core piece 10 ″ when viewed in plan, and the line Or ″ is the recess 10r ″ or the caulking. This is a center line passing through the center of the through hole 10w ″ in plan view, and the line Ot ″ and the line Or ″ coincide with each other as shown in FIGS.

In such a conventional method of manufacturing the laminated core 52, when the core piece 10 ″ is punched out of the thin metal plate 11 as shown in FIG. Since the concave portion 14 ″ having the arc portion 13 ″ larger than the circular arc of the circular convex portion is arranged, the caulking projection 10t ″ that is the circular convex portion enters without being interfered with the concave portion 10r ″, and the caulking projection 10t '' is press-fitted into the straight part 14 '' of the recess 10r '', and caulking is achieved.
FIG. 7 is a conceptual cross-sectional view showing the outer shape of the core piece shown in FIG.
Japanese Patent No. 3848804

  By the way, in the manufacturing method of the laminated core shown in FIG. 5 described above, the caulking protrusion 10t ″ of the core piece 10 ″ is formed from a convex portion that is circular when viewed in plan, and the recess 10r ″ is formed on the plane. Is formed of an arc portion 13 ″ larger than the circular arc of the circular convex portion and a linear portion 14 ″ provided at the inner position of the circular convex portion of the circular convex portion and into which the circular convex portion is press-fitted, and 7 when the outer shape is punched as shown in FIG. 7, in the direction in which the punching of the iron core piece 10 ″ occurs, the arc portion 13 ″ of the recess 10r ″ larger than the circular convex portion is arranged and caulking is performed. A recess having an arc portion 13 ″ larger than the circular arc of the circular protrusion of the caulking projection 10t ″ is arranged in the direction in which the pulling warpage occurs, and the circular protrusion enters the recess 10r ″ without interfering with the recess. Therefore, even if the warping occurs, the possibility that the caulking protrusion 10t ″ is not inserted into the recess 10r ″ is prevented as much as possible, and the possibility that the iron core piece 10 ″ is deformed is prevented as much as possible. Therefore, it is possible to prevent a gap from being formed between the layers of the manufactured core 10 ″ of the laminated core 52 as much as possible.

  However, since the arc portion 13 ″ of the recess 10r ″ has a larger diameter than the circular projection of the caulking projection 10t ″, the caulking projection 10t ″ moves in the horizontal direction within the arc portion 13 ″ of the recess 10 ″. There was something to do. Further, since the caulking projection 10t ″ is caulked and coupled only in two directions of the concave linear portion 14 ″, the caulking coupling is weak, and accordingly, depending on the direction of the external force acting on the laminated core 52, unintended impact, etc. As a result, the caulking bond may be loosened. Therefore, in the method of manufacturing the laminated core 52 of FIG. 5, there are still problems that the caulking strength of the caulking connection is weak and the shape accuracy of the uprightness and the plane parallelism in the laminated core 62 is deteriorated.

  In view of the circumstances described above, the present invention has an object to provide a method for manufacturing a laminated core that produces a laminated core having a strong caulking strength of caulking and having excellent shape accuracy characteristics of uprightness and plane parallelism in the laminated core. And

  In order to solve the above-described problems, the present invention provides an iron core piece in which a caulking protrusion is formed on one side surface and a recess is formed on the other side surface or a caulking through hole penetrating from one side surface to the other side surface is formed. In the method of manufacturing a laminated core in which the caulking protrusion is inserted into a recess or a caulking through hole for another iron core piece, and the iron core piece is caulked and laminated to the other iron core piece, the caulking protrusion of the iron core piece is inserted into the caulking protrusion. Forming a center line passing through the center of the surface when viewed in plan so that the center line is located closer to the center side of the core piece than a center line passing through the center of the surface when viewing through the recess or caulking through hole. It is characterized by that.

  The method of manufacturing a laminated core according to the present invention is the above-described caulking of an iron core piece in which a caulking projection is formed on one side surface and a recess is formed on the other side surface or a caulking through hole penetrating from one side surface to the other side surface is formed. In a method for manufacturing a laminated core in which a protrusion is inserted into a recess or a caulking through hole of another iron core piece, and the iron core piece is caulked and laminated to the other iron core piece, the caulking protrusion of the iron core piece is flattened. The center line passing through the center of the surface when viewed is formed so as to be positioned closer to the center side of the core piece than the center line passing through the center of the surface when viewed through the recess or the caulking through hole. From this, even when the iron core piece is warped and drawn into the die, it is possible to prevent as much as possible the possibility of gaps between the layers of the iron core pieces of the laminated iron core due to poor insertion of caulking protrusions, The caulking projection is recessed By preventing the horizontal movement in the caulking through-hole as much as possible and by caulking the caulking projections around the entire circumference, the iron core pieces are strongly caulked to the previously laminated iron core pieces in any direction. Even when a shocking external force (load) is accidentally applied to the core, the caulking connection is not loosened, and it is possible to manufacture a high-quality multilayer core with excellent shape accuracy such as perpendicularity and plane flatness in the multilayer core. .

  The manufacturing method of the laminated core of the present invention will be described in detail in the following examples.

FIG. 1 is a conceptual perspective view showing a laminated core manufactured by the method for manufacturing a laminated core according to an embodiment of the present invention.
As shown in FIG. 1, the laminated iron core 1 is formed by punching the outer shape of the iron core piece 10 into a predetermined shape from a thin metal plate 11 such as an electromagnetic steel plate by a press die device, and caulking the punched iron core piece 10 to another iron core piece 10. It is manufactured by laminating.

FIG. 2 is a view showing a state in which the outer shape of the iron core is punched in the method for manufacturing a laminated core according to the embodiment of the present invention. In particular, FIG. 2 (a) shows that the caulking protrusion is inserted into the recess immediately after the outer shape punching. FIG. 2B is a conceptual cross-sectional view showing a state in which the caulking protrusion is inserted into the recess and is caulked and joined. 2 to 8, the same parts as those in FIG. 1 are denoted by the same reference numerals.
In order to manufacture the laminated iron core 1, the caulking protrusion 10t is formed on one side surface of the thin metal plate 11 before the outer shape punching process of the iron core piece 10 shown in FIG. Further, before punching out the outer shape of the iron core piece 10, the caulking protrusion 10t is formed on the other side surface of the thin metal plate 11, thereby forming the recess 10r or the caulking through hole 10w penetrating from one side surface to the other side surface.
Next, the outer shape of the iron core piece 10 is punched out from the metal thin plate 11, and the caulking protrusion 10 t is inserted into the recess 10 r of the other iron core piece 10 or the caulking through hole 10 w, and the iron core piece 10 is attached to the other iron core piece 10. Caulking and laminating. Then, the laminated iron core 1 that has been caulked and bonded is taken out of the die 32.
When the iron core piece 10 is caulked and laminated to another iron core piece 10, the center line Oa (FIG. 1) of the iron core piece 10 is matched with the center line Oa of the other iron core piece 10 to be caulked as in the conventional case. I have to.

FIG. 3 is a view showing the structure of the iron core piece constituting the laminated iron core of FIG. 1. In particular, FIG. 3 (a) is a conceptual plan view of the iron core piece, and FIG. 3 (b) is an AA concept of FIG. 3 (a). FIG. 3C is a conceptual plan view showing the shape and positional relationship of caulking protrusions formed on one side surface of the core piece and recesses formed on the other side surface.
FIG. 3A shows a state of the iron core piece 10 whose outer shape is punched out from the metal thin plate 11 into a predetermined shape by a press die device. As shown in FIG. 3B, a caulking protrusion 10 t is formed on one side surface 10 a of the iron core piece 10. Further, the iron core piece 10 is formed with a recess 10r on the other side surface 10b or a caulking through hole 10w penetrating from the one side surface 10a to the other side surface 10b. 3A to 3C representatively show a state in which the recess 10r is formed on the other side surface 10b of the iron core piece.

As shown in FIG. 3 (a), the other side surface 10b of the iron core piece 10 has a plurality of recesses 10r or through holes 10w (eight in the embodiment) formed on the inner diameter side 10i. A plurality (eight in the embodiment) are formed in 10u.
In addition, the iron core piece 10 has a plurality of caulking protrusions 10t (eight in the embodiment) on the inner diameter side 10i corresponding to each recess 10r or each through hole 10w on one side surface 10a, and the outer diameter. Plurals (eight in the embodiment) are formed on the side 10u.

In the step of forming the caulking protrusion 10t described above, as shown in FIG. 3C, the shape of the caulking protrusion 10t in plan view (circular shape in the embodiment) is the flat surface of the recess 10r or the caulking through hole 10w. The caulking protrusion 10t is formed so as to have the same shape as viewed.
As shown in FIGS. 3B and 3C, the center line Ot passing through the center of the surface when the caulking protrusion 10t is viewed in plan is the surface when the dent 10r or the caulking through hole 10w is viewed in plan. The caulking protrusion 10t is formed so as to be located on the center Oa side of the iron core piece 10 with respect to the center line Or passing through the center.
In FIG. 3C, the caulking protrusion 10t and the recess 10r on the outer diameter side 10u are illustrated, the caulking protrusion 10t is illustrated by a chain line, and the recess 10r is illustrated by a solid line. Further, the center line Ot and the center line Or are lines that are arranged in a straight line with the center Oa of the laminated core 1 when the laminated core 1 is viewed in plan as shown in FIG.
The caulking protrusions 10t and the recesses 10r are formed by a processing and forming apparatus in which the forming punch and the die are arranged with the center line shifted.

Further, when the outer shape of the iron core piece 10 is punched out by the punch 31, warping occurs. However, in the method for manufacturing a laminated core of the present invention, as shown in FIG. 3, the center line Ot passing through the center of the caulking protrusion 10t when the caulking protrusion 10t is viewed in plan is the recess 10r or the caulking through hole. A step of forming the core piece 10 so as to be located on the center Oa side of the core piece 10 with respect to the center line Or passing through the center of the plane in the plan view of 10w is provided. Therefore, as shown in FIG. 2, the caulking protrusion 10t that has been warped is inserted into the recess 10r without being interfered (contacted) with the other side surface 10b and is caulked and coupled. Therefore, the insertion failure of the caulking protrusion 10t is prevented as much as possible, and thereby the caulking lamination is performed without generating a gap between the layers of the iron core pieces 10.
Therefore, it is possible to manufacture a laminated core having a strong caulking strength of the caulking connection and excellent shape accuracy characteristics of uprightness and plane parallelism in the laminated core.

That is, when the iron core piece 10 is extracted from the thin metal plate 11 and extracted into the die 32, the caulking protrusion 10t of the iron core piece 10 is first laminated on the laminated iron core 1 in the die 32 while being warped upward. Therefore, the caulking protrusion 10t to be extracted is inclined toward the outer peripheral side of the iron core piece 10 as shown in FIG.
However, the center line Ot when the caulking projection 10t is viewed in plan is more than the center line Or passing through the center of the surface when the other core piece 10 has a recess 10r or a caulking through hole 10w when viewed in plan. In other words, the center line Or of the recess 10r or the caulking through hole 10w is located closer to the outer peripheral side of the core piece 10 than the center line Ot of the caulking protrusion 10t. Therefore, the caulking protrusion 10t that is tilted by warping is smoothly fitted into the caulking recess 10r or the caulking through hole 10w of the other iron core piece 10, and deformation of the iron core piece 10 is prevented as much as possible. It is possible to prevent gaps between the layers as much as possible.

  Further, since the shape of the caulking protrusion 10t when viewed in plan is the same as that of the recess 10r or the through hole 10w, there is a possibility that the caulking protrusion 10t moves horizontally within the recess 10r or the through hole 10w as much as possible. Since it is prevented, the caulking force is strengthened. Further, since the caulking coupling by fitting is performed by the recess 10r or the through hole 10w on the entire outer periphery of the caulking protrusion 10t, the caulking coupling force extends equally and firmly from the entire circumference of the caulking protrusion 10t. Therefore, as compared with the conventional case where the caulking protrusion 10t ″ is caulked and coupled only by two directions of the linear portion 14 ″ of the recess 10r ″ (FIG. 5), the external force (load) acting on the laminated core 1 is reduced. Therefore, even when an external force (load) such as an unintended impact is accidentally applied, the caulking connection is prevented from being loosened as much as possible. Therefore, it is possible to manufacture a high-quality laminated core 1 that has a strong crimping strength and has excellent shape accuracy characteristics depending on the squareness and surface flatness of the laminated core 1.

  In the method for manufacturing the laminated core 1 of this embodiment, the caulking protrusion 10t formed in the caulking protrusion 10t forming process has been described as having a circular shape (round shape) when the caulking protrusion 10t is viewed in plan. However, the shape of the caulking protrusion 10t is not limited to that of this embodiment. For example, the caulking protrusion 10t may have a rectangular shape (square shape) when viewed in plan, or may have a V-shaped cross section (V shape).

  Further, as shown in FIGS. 3B and 3C, in the method for manufacturing the laminated core 1 of the present invention, at least the caulking protrusion 10t on the outer diameter side 10u is formed in the caulking protrusion 10t in the step of forming the caulking protrusion 10t. The center line Ot passing through the center of the surface when 10t is viewed in plan is located closer to the center Oa side of the core piece 10 than the center line Or passing through the center of the surface when viewing the recess 10r or the caulking through hole 10w in plan. As long as it is formed as described above. For example, the center line Ot of the caulking protrusion 10t on the inner diameter side 10i may coincide with the center line Or of the recess 10r or the caulking through hole 10w.

In this embodiment, the manufacturing method of the present invention is applied to all caulking protrusions 10t on the outer diameter 10u side of the laminated core 1, but the caulking protrusions 10t formed by this manufacturing method are on the outer diameter 10u side. Needless to say, any of the caulking protrusions 10t may be arbitrarily selected.
Further, the outer shape of the iron core piece 10 is circular in this embodiment, but the present invention can be applied to an iron core piece having an arbitrary outer shape.

  The method for manufacturing a laminated core according to the present invention can be effectively applied as a method for manufacturing a stator and a rotor of various electric motors.

FIG. 1 is a conceptual perspective view showing a laminated core manufactured by the method for manufacturing a laminated core according to an embodiment of the present invention. FIG. 2 is a view showing a state in which the outer shape of the iron core is punched in the method for manufacturing a laminated core according to the embodiment of the present invention. In particular, FIG. 2 (a) shows that the caulking protrusion is inserted into the recess immediately after the outer shape punching. FIG. 2B is a conceptual cross-sectional view showing a state in which the caulking protrusion is inserted into the recess and is caulked and joined. FIG. 3 is a view showing the structure of the iron core piece constituting the laminated iron core of FIG. 1. In particular, FIG. 3 (a) is a conceptual plan view of the iron core piece, and FIG. 3 (b) is an AA concept of FIG. 3 (a). FIG. 3C is a conceptual plan view showing the shape and positional relationship of caulking protrusions formed on one side surface of the core piece and recesses formed on the other side surface. FIG. 4 is a conceptual cross-sectional view showing a state in which the outer shape of the core piece is punched out from a thin metal plate such as an electromagnetic steel sheet and caulked and laminated in a conventional method of manufacturing a laminated core. FIG. 5 is a conceptual plan view showing the shape and positional relationship of caulking protrusions formed on one side of a core piece of a laminated core manufactured by a conventional method of manufacturing a laminated core and recesses formed on the other side. 6 is a conceptual cross-sectional view of the iron core piece of FIG. FIG. 7 is a conceptual cross-sectional view showing a state of external punching of the iron core piece of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Laminated core 10 ... Iron core piece 10a ... One side surface 10b ... Other side surface 10r ... Indentation 10t ... Caulking protrusion 10w ... Caulking through hole Oa ... Center of iron core piece Ot ... Center passing through the center of the plane when the caulking protrusion is viewed in plan Line Or: Center line passing through the center of the surface when the recess or caulking through hole is viewed in plan

Claims (1)

A caulking protrusion is formed on one side surface and a recess is formed on the other side surface or a caulking through-hole for penetrating from one side surface to the other side surface is formed. In the manufacturing method of the laminated core, which is inserted into the through hole for caulking, and the iron core piece is caulked and laminated to the other iron core piece,
The iron core piece has a center line that passes through the center of the surface when the caulking protrusion is viewed in plan, and the center line that passes through the center of the surface when the recess or the through hole for caulking is viewed in plan. A method of manufacturing a laminated iron core, comprising a step of forming the piece so as to be positioned on the center side of the piece.

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