JP2011109834A - Motor stator of divided structure, and method and device for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor stator of divided structure capable of striking a balance between a high precision assemblability and a reduction of iron loss while driving a motor. <P>SOLUTION: The motor stator 30 includes a plurality of stator pieces 50, which are composed by laminating a plurality of stator piece plates 60, and which are arranged annularly. The motor stator 30 includes the stator piece plate 60 which is formed with a yoke part 62 of circular arc shape and a teeth part 61 projecting from the yoke part 62 to an inside of the yoke part in a radial direction. The Vickers hardness of a side surface of the teeth part 61a is lower than that of other side surface of a stator piece plates 60. A shear plane ratio of the yoke part 62 is greater than that of other side surface of the stator piece plate 60. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a motor stator having a divided structure in which stator pieces configured by laminating stator piece plates are arranged in an annular shape, and a method and apparatus for manufacturing the motor stator.

2. Description of the Related Art Conventionally, a split-structure motor stator technique in which stator pieces configured by stacking stator piece plates are arranged in an annular shape has been publicly known. The stator piece plate includes an arcuate yoke portion and a tooth portion protruding inward in the yoke portion radial direction from the yoke portion, and the stator piece abuts the side surface of the adjacent stator piece in the yoke portion circumferential direction. The technology of a motor stator having a divided structure arranged in an annular shape is also known.
For example, Patent Document 1 discloses a configuration of a motor stator having a divided structure including a stator piece plate that is stamped and formed by press working.

However, when the stator piece plate is punched and formed by press processing, when the stator piece plate is punched and formed by low speed press, the distortion of the side surface of the teeth portion that is a part of the side surface of the stator piece plate increases. Iron loss increases when the motor is driven.
On the other hand, when the stator piece plate is punched and formed by a high-speed press in order to reduce the distortion on the side surface of the tooth portion and reduce the iron loss when the motor is driven, the yoke portion which is a part of the side surface of the stator piece plate is formed. Since the shear surface ratio of the side surface is reduced, the assembly accuracy when the stator pieces are arranged in an annular shape is lowered.

JP 2003-284269 A

  The problem to be solved by the present invention is to provide a motor stator having a split structure that can achieve both high-precision assembly of the motor stator and reduction of iron loss when the motor is driven, and a method and apparatus for manufacturing the motor stator. is there.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

  That is, in claim 1, a motor stator having a divided structure in which a plurality of stator pieces configured by laminating a plurality of stator piece plates are annularly arranged, the stator piece plate includes an arcuate yoke portion, A tooth portion projecting inwardly in the yoke portion radial direction from the yoke portion, and the stator pieces have surfaces formed by side surfaces in the yoke portion circumferential direction of the yoke portions of the stacked stator piece plates. The Vickers hardness of the side surface in the circumferential direction of the yoke portion in the teeth portion of the stator piece plate is a Vickers hardness lower than the Vickers hardness of the other side surface of the stator piece plate, and the yoke in the yoke portion of the stator piece plate The shear surface ratio of the side surface in the circumferential direction is larger than the shear surface ratio of the other side surface of the stator piece plate. A motor stator of the split structure to be cross ratio.

  According to a second aspect of the present invention, there is provided a method of manufacturing a motor stator having a split structure in which a plurality of stator pieces each having a plurality of stator piece plates stacked in an annular shape are arranged, wherein the stator piece plate includes an arcuate yoke portion and A tooth portion projecting inwardly in the yoke portion radial direction from the yoke portion, and each stator piece has a surface constituted by a side surface in the yoke portion circumferential direction of the yoke portion of the laminated stator piece plate. The stator piece plates are brought into contact with each other, and the stator piece plates are formed by stamping a material by press working. This is a method for manufacturing a motor stator having a divided structure.

  According to a third aspect of the present invention, there is provided a motor stator manufacturing apparatus having a split structure in which a plurality of stator pieces configured by laminating a plurality of stator piece plates are arranged annularly, wherein the stator piece plate includes an arcuate yoke portion and A tooth portion projecting inwardly in the yoke portion radial direction from the yoke portion, and each stator piece has a surface constituted by a side surface in the yoke portion circumferential direction of the yoke portion of the laminated stator piece plate. The manufacturing apparatus includes a mold for punching a material by press working to form the stator piece plate, and the mold includes a first punch for punching a tooth portion of the stator piece plate, and the stator. A second punch for punching the yoke portion of the one plate, and the first punch and the second punch are moved in the press direction by a crank motion. Is configured moving, punching position of punching out the material of the second punch, than punching position of punching out the material of the first punch, those located near the bottom dead center in the crank movement.

  According to the motor stator having the split structure of the present invention and the manufacturing method and apparatus thereof, it is possible to achieve both high-precision assembly of the motor stator and reduction of iron loss when driving the motor.

1 is a cross-sectional view showing an overall configuration of a motor according to an embodiment of the present invention. The perspective view which shows the motor stator of a divided structure similarly. The perspective view which similarly shows a stator piece plate. The flowchart which shows the manufacturing process of the motor stator of the division structure which concerns on embodiment of this invention. The schematic diagram which similarly shows the punching process. The schematic diagram which shows the manufacturing apparatus of the motor stator of the division structure which concerns on embodiment of this invention. The graph which similarly shows the correlation of the operation | movement of punch and punching speed.

Next, embodiments of the invention will be described.
FIG. 1 is a cross-sectional view showing an overall configuration of a motor according to an embodiment of the present invention, FIG. 2 is a perspective view showing a motor stator having a divided structure, and FIG. 3 is a perspective view showing a stator piece plate.
FIG. 4 is a flowchart showing a manufacturing process of a motor stator having a divided structure according to an embodiment of the present invention, FIG. 5 is a schematic diagram showing a punching process, and FIG. 6 is a diagram of a motor stator having a divided structure according to an embodiment of the present invention. It is a schematic diagram which shows a manufacturing apparatus.
FIG. 7 is a graph showing the correlation between the punching operation and the punching speed.

A motor 10 according to an embodiment of a motor stator having a divided structure will be described with reference to FIG.
1 to 3, the direction indicated by the arrow A, that is, the circumferential direction of the motor 10, is the yoke portion circumferential direction, the direction indicated by the arrow B, ie, the radial direction of the motor 10, is the yoke portion radial direction, and the direction indicated by the arrow C. Is the motor shaft direction.

  The motor 10 is a brushless motor, and includes a housing 11, a motor rotor 20, and a motor stator 30. The housing 11 is made of aluminum and is formed in a cylindrical shape whose axial direction is the motor axial direction. The motor rotor 20 is disposed coaxially with the housing 11 and is configured to be rotatable relative to the housing 11 about the motor shaft. The motor stator 30 is arranged coaxially with respect to the housing 11.

  The motor rotor 20 is a permanent magnet type rotor, and includes a shaft 21, a rotor core 22, and a permanent magnet 23. The shaft 21 is disposed coaxially with the axis of the housing 11 and is supported so as to be rotatable relative to the housing 11. The rotor core 22 is disposed on the outer periphery of the shaft 21, and is disposed so as to be coaxially fixed with respect to the shaft 21 so as to be rotatable integrally with the shaft 21. The permanent magnets 23 are arranged with the same angle shifted so that a plurality of the permanent magnets 23 are arranged at equal intervals in the circumferential direction of the yoke portion, and are housed through the rotor core 22 in the motor axis direction.

  The motor stator 30 is a stator and includes a fastening ring 31 and a stator core 40. The fastening ring 31 is disposed so as to be coaxial with the housing 11. The stator core 40 is arranged coaxially with respect to the fastening ring 31.

The stator core 40 will be described with reference to FIG.
The stator core 40 is formed in a cylindrical shape by arranging a plurality of stator pieces 50 in an annular shape in the circumferential direction of the yoke portion. In order to form the stator core 40 by arranging the plurality of stator pieces 50 in an annular shape, the side surfaces of the adjacent stator pieces 50 in the circumferential direction of the yoke portion are in contact with each other. In other words, the stator core 40 is divided into a plurality of stator pieces 50 in the circumferential direction of the yoke portion. That is, the motor stator 30 is a split structure type motor stator.

  The stator piece 50 is configured by laminating a plurality of stator piece plates 60. The stator piece 50 includes a winding surface 51a and a fitting surface 52a. The winding surface 51a is a side surface around which a coil (not shown) is wound, and is a side surface in the yoke portion circumferential direction of the stator piece 50, and is a surface located on the inner side in the yoke portion radial direction. The winding surface 51a is a surface constituted by a tooth portion side surface 61a of the stator piece plate 60 described later.

  The mating surface 52a is a side surface that comes into contact with adjacent stator pieces 50 when the plurality of stator pieces 50 are arranged in an annular shape, and is a side surface in the yoke portion circumferential direction, and the winding surface 51a in the yoke portion radial direction. It is a surface located outside. The fitting surface 52a is a surface constituted by a yoke portion side surface 62a of the stator piece plate 60 described later.

The stator piece plate 60 will be described with reference to FIG.
The stator piece plate 60 is formed, for example, by punching a magnetic steel sheet 70 (see FIG. 5) having a thickness of 0.3 mm as a material by press working. The stator piece plate 60 includes a yoke portion 62 and a teeth portion 61. The yoke portion 62 is formed in an arc shape, and has an outer side surface 62b that is an outer side surface in the yoke portion radial direction, an inner diameter side surface 62c that is an inner side surface in the yoke portion radial direction, and both sides in the yoke portion circumferential direction. And a yoke side surface 62a, which is a surface. The mating surface 52a of the stator piece 50 is constituted by the yoke portion side face 62a of the plurality of stacked stator piece plates 60.

  The teeth portion 61 is formed so as to protrude from the inner diameter side surface 62c of the yoke portion 62 toward the inside in the yoke portion radial direction, and is formed in a rectangular shape whose longitudinal direction is the yoke portion radial direction. The teeth portion 61 includes an axial side surface 61b that is an inner side surface in the yoke portion radial direction, and a teeth portion side surface 61a that is both side surfaces in the yoke portion circumferential direction. The winding surface 51 a of the stator piece 50 is configured by the tooth portion side surface 61 a of the plurality of stacked stator piece plates 60.

  Here, it has been found that the distortion that occurs when the stator piece plate 60 is formed by stamping by stamping affects the iron loss when the motor 10 is driven. In particular, the distortion caused by the punching process of the teeth side surface 61a of the stator piece plate 60 greatly affects the iron loss when the motor 10 is driven, as compared with the distortion caused by the punching process of the other side face of the stator piece plate 60. I know.

  The distortion caused by the punching process is distortion hardening of the material after the punching process, and can be represented by Vickers hardness instead. That is, the greater the distortion due to punching, the higher the Vickers hardness. In addition, Vickers hardness is one of the scales showing the hardness of an industrial material, and is a kind of indentation hardness.

  That is, in order to reduce the iron loss when driving the motor 10, it is necessary to reduce the distortion of the stator piece plate 60 due to the punching process. In particular, it is necessary to reduce the distortion of the teeth side surface 61a of the stator piece plate 60. Further, the fact that the distortion of the stator piece plate 60 due to the punching process is small is expressed by the low Vickers hardness.

  Further, when the stator core 50 is manufactured by assembling the stator pieces 50 in an annular shape, the adjacent stator pieces 50 are assembled by fitting the fitting surfaces 52a to each other (see an assembly step S130 described later). Here, in order to assemble the stator core 40 with high accuracy, it is necessary that the shearing surface ratio of the mating surface 52a is large. In other words, since the fitting surface 52a is constituted by the yoke side surface 62a, the shearing surface ratio of the yoke side surface 62a needs to be large.

  The shear surface ratio is the ratio of the height of the surface cut by the pressing shear force while the teeth of the press (punched surface) are in contact with the height of the side surface of the material to be punched, and the cut surface. This is the ratio of the height of the surface that has undergone additional machining by shaving. Further, there is no particular correlation between the Vickers hardness and the shear plane ratio.

  In view of the above, in order to achieve both high-precision assembly of the stator core 40 and reduction of iron loss when the motor 10 is driven, the Vickers hardness of the side surface 61a of the tooth portion is higher than that of the other side surface of the stator piece plate 60. Therefore, it is necessary to provide the motor stator 30 including the stator piece plate 60 having a lower shearing ratio of the yoke portion side face 62a than that of the other side face of the stator piece plate 60.

An embodiment relating to a method for manufacturing a motor stator having a divided structure will be described with reference to FIG.
The manufacturing process of the motor stator 30 includes a punching process S110, a stacking process S120, an assembling process S130, and a shrink fitting process S140. The punching step S110 is a step of stamping and forming the stator piece plate 60 from the electromagnetic steel plate 70 by press working. The details of the punching step S110 will be described later.

  The stacking step S120 is a step of manufacturing the stator piece 50 by stacking the stator piece plates 60 punched in the punching step S110. The assembly step S130 is a step of manufacturing the stator core 40 by arranging the stator pieces 50 manufactured in the stacking step S120 in an annular shape in the yoke portion circumferential direction. The shrink fitting process S140 is a process for manufacturing the motor stator 30 by fixing the stator core 40 manufactured in the assembly process S130 to the fastening ring 31 by shrink fitting.

The punching step S110 will be described with reference to FIG.
The punching step S110 is a step of punching the stator piece plate 60 from the electromagnetic steel plate 70 by press working. Here, in the press working of the stator piece plate 60, the punching speed when the teeth side surface 61a is punched by press working is set to be faster than the punching speed when the yoke side surface 62a is punched. Here, the punching speed refers to the speed at which the punching surface of the punch for punching the material passes through the material.

  The punching step S110 includes a first stage and a second stage as a punching stage. It is assumed that the first work 71 is punched in the first stage and the stator piece plate 60 as the second work is punched in the second stage.

  Specifically, in the first stage, the first workpiece 71 is punched at a punching speed V1 (high-speed press) in order to form the teeth side surface 61a of the stator piece plate 60 from the electromagnetic steel plate 70. Further, in the second stage, in order to form the yoke side surface 62a of the stator piece plate 60 from the electromagnetic steel plate 70 that has passed through the first stage, the stator piece plate 60 as the second workpiece is punched at a punching speed V2 (low speed). press). Here, the punching speed V1 is faster than the punching speed V2.

  Here, the correlation between the punching speed and the Vickers hardness in the punching by press working of the metal material will be described. Here, it is known that the higher the punching speed, the lower the Vickers hardness. That is, the end face of the workpiece punched out by the high-speed press has a low Vickers hardness. On the other hand, the end face of the workpiece punched out by the low speed press has a higher Vickers hardness than the end face of the workpiece punched out by the high speed press.

  In consideration of the above, in the stator piece plate 60, the Vickers hardness of the tooth portion side surface 61a formed in the first stage is equal to the side surface of the other stator piece plate 60 formed in the second stage (axial side surface 61b, yoke portion). The Vickers hardness of the side surface 62a and the outer diameter side surface 62b) is lower.

  In this way, in the stator piece plate 60, the Vickers hardness of the tooth side surface 61a is smaller than the Vickers hardness of the yoke side surface 62a, and therefore iron loss when driving the motor 10 is efficiently reduced. be able to.

  In addition, the correlation between the press speed and the shear plane ratio in the punching of the metal material by press working will be described. Here, it is known that the slower the punching speed, the larger the shear surface ratio after press working. That is, the end surface of the workpiece punched out by the high-speed press has a small shear surface ratio. On the other hand, the end face of the workpiece punched out by the low speed press has a large shear surface ratio.

  Based on the above, in the stator piece plate 60, the shear surface ratio of the yoke part side face 62a formed in the second stage is the side face of the other stator piece plate 60 formed in the first stage (the teeth part side face 61a and the inner diameter). It is larger than the shear surface ratio of the side surface 62c).

  Thus, in the stator piece plate 60, the shearing surface ratio of the yoke part side surface 62a is larger than the shearing surface ratio of the tooth part side surface 61a. The surface ratio is larger than the shear surface ratio of the winding surface 51a constituted by the tooth portion side surface 61a. Therefore, when the stator core 40 is manufactured by assembling the stator pieces 50 in an annular shape, the stator core 40 can be assembled with high accuracy.

  Based on the above, the split-structure motor stator 30 can achieve both high-precision assembly when assembling the stator core 40 and reduction of iron loss when driving the motor 10.

An embodiment relating to a motor stator manufacturing apparatus having a divided structure will be described with reference to FIG.
The stator piece plate manufacturing apparatus 80 is an apparatus that punches out the stator piece plate 60 with one mold. It is assumed that the electromagnetic steel sheet 70 advances through the stator piece plate manufacturing apparatus 80 in the direction of arrow P. The stator piece plate manufacturing apparatus 80 includes a first punch 81, a second punch 82, a punch block 83, a crank mechanism 85, and a die 87. The first punch 81, the second punch 82, the punch block 83, and the die 87 constitute one die.

  The crank mechanism 85 is a mechanism that presses the punch block 83 in the direction (vertical direction) indicated by the arrow P in FIG. 6 by rotationally driving the motor (not shown) in the direction indicated by the arrow R in FIG. That is, the punch block 83 reciprocates in the press direction by converting the rotational motion of the motor into reciprocating motion by the crank mechanism 85. The die 87 supports the electromagnetic steel sheet 70 sent in the direction of the arrow P.

  The first punch 81 is a punch for punching out the electromagnetic steel sheet 70 in the first stage, and is fixed to the lower surface of the punch block 83. The second punch 82 is a punch for punching out the electromagnetic steel sheet 70 in the second stage, and is fixed to the lower surface of the punch block 83. That is, the first punch 81 and the second punch 82 are both fixed to the punch block 83 and are provided in one mold, and the crank motion in which the rotational motion is converted into the reciprocating motion by the crank mechanism 85 is performed. It is configured to reciprocate in the pressing direction (the punching direction of the electromagnetic steel sheet 70) by the driving force to be performed.

  The punch height of the first punch 81 is H1. The punch height of the second punch 82 is H2. Here, the punch height refers to the distance from the lower surface of the punch block 83 to the punching surface (lower surface) of each punch (first punch 81 and second punch 82). The punch height H1 is higher than the punch height H2.

  As described above, in the first stage, the first work 71 is punched from the electromagnetic steel plate 70, and in the second stage, the stator piece plate 60 is punched from the electromagnetic steel plate 70.

  With this configuration, in the electromagnetic steel sheet 70 conveyed in the stator piece plate manufacturing apparatus 80, first, the first work 71 is punched out by the first punch 81 in the first stage, and then the second On the stage, the stator piece plate 60 as the second workpiece is punched out by the second punch 82.

  The correlation between the operations of the first punch 81 and the second punch 82 and the punching speeds V1 and V2 in the stator piece plate manufacturing apparatus 80 will be described with reference to FIG. FIG. 7 is a graph showing, in time series t, the height position L in the pressing direction of the punched surfaces of the first punch 81 and the second punch 82 during the operation of the stator piece plate manufacturing apparatus 80. Time t and the vertical axis represent the height position L of the punched surface. Moreover, the broken line represents the position (height position) in the pressing direction of the electromagnetic steel sheet 70 that moves in the stator piece plate manufacturing apparatus 80.

  The height position L1 in the pressing direction of the punching surface of the first punch 81 and the height position L2 in the pressing direction of the punching surface of the second punch 82 are H1-H2 minutes, which are the difference in punch height in the same phase. It is expressed as a sine curve having a positional deviation of. When the height position L1 and the height position L2 reach the height position of the electromagnetic steel sheet 70 from a place higher than the height position of the electromagnetic steel sheet 70, the first punch 81 and the second punch 82 are electromagnetic It is the punching position of the first punch 81 and the second punch 82 for punching the steel plate 70.

  In the graph showing the height position L1 and the height position L2 in time series, the height of the electromagnetic steel sheet 70 as the material, that is, the slope of the graph at the punching position of the first punch 81 and the second punch 82, The punching speed is shown. The larger the slope of the graph, the faster the punching speed, and the smaller the slope, the slower the punching speed.

  Here, the inclination (the arrow V1 in the figure) of the height position L1 at the punching position, which represents the punching speed V1 of the first punch 81, represents the punching speed V2 of the second punch 82 at the height position L2 at the punching position. The inclination is larger than the inclination (arrow V2 in the figure).

  That is, the punching position where the second punch 82 punches the electromagnetic steel sheet 70 in the second stage is located close to the minimum point on the sine curve indicating the change in the height position L2. On the other hand, the punching position where the first punch 81 punches the electromagnetic steel sheet 70 in the first stage is located near the center of the local maximum point and the local minimum point in the sine curve indicating the change in the height position L1. That is, the punching position of the second punch 82 is located closer to either the minimum point or the maximum point of the sine curve than the punching position of the first punch 81.

  In addition, since the slope of the sine curve becomes smaller as it approaches the local minimum and maximum points of the sine curve, the inclination of the height position L1 at the punching position is larger than the inclination of the height position L2 at the punching position. Accordingly, the punching speed V1 of the first punch 81 is faster than the punching speed V2 of the second punch 82. In other words, since the punching position of the second punch 82 is closer to the bottom dead center of the operation by the crank motion of each punch 81 and 82 than the punching position of the first punch 81, the punching speed V1 is faster than the punching speed V2. It can be said.

  With such a configuration, in the same mold, the punching speed V1 of the first stage can be made faster than the punching speed V2 of the second stage.

  Thus, the stator piece plate manufacturing apparatus 80 having a plurality of punching surfaces with different punching speeds in the same mold can be provided. That is, it is possible to manufacture a motor stator 30 having a divided structure that can achieve both high-precision assembly when assembling the stator core 40 and reduction of iron loss when driving the motor 10 with one mold.

As another embodiment of the punching step S110 of the stator core 40, the yoke side surface 62a may be shaved after the stator piece plate 60 is punched out by a high-speed press (punching speed V1).
For example, the yoke portion side surface 62a can be shaved after the teeth side surface 61a and the yoke portion side surface 62a of the stator piece plate 60 are simultaneously punched out by a high-speed press. Alternatively, the teeth side surface 61a of the stator piece plate 60 can be punched with a high-speed press, and after the yoke side surface 62a of the stator piece plate 60 has been punched, the yoke side surface 62a can be shaved.

  Thus, by shaving the yoke side surface 62a, the shear surface ratio of the yoke side surface 62a punched out by the high-speed press can be increased, and the stator core 40 can be assembled with high accuracy.

DESCRIPTION OF SYMBOLS 10 Motor 20 Motor rotor 30 Motor stator 40 Stator core 50 Stator piece 51a Winding surface 52a Fitting surface 60 Stator piece plate 61a Teeth part side surface 62a York part side surface 70 Electromagnetic steel plate 80 Stator piece plate manufacturing apparatus

Claims (3)

A motor stator having a divided structure in which a plurality of stator pieces each having a plurality of stator piece plates stacked in an annular shape are arranged,
The stator piece plate includes an arc-shaped yoke portion, and a teeth portion protruding from the yoke portion to the inside in the yoke portion radial direction,
The stator pieces are in contact with each other at surfaces formed by side surfaces in the yoke portion circumferential direction of the yoke portions of the stacked stator piece plates,
The Vickers hardness of the side surface in the yoke portion circumferential direction in the teeth portion of the stator piece plate is a Vickers hardness lower than the Vickers hardness of the other side surface of the stator piece plate,
The motor stator having a split structure in which a shear surface ratio of a side surface in the yoke portion circumferential direction in the yoke portion of the stator piece plate is larger than a shear surface ratio of the other side surface of the stator piece plate. A method of manufacturing a motor stator having a split structure in which a plurality of stator pieces each having a plurality of stator piece plates stacked in an annular shape are arranged,
The stator piece plate includes an arc-shaped yoke portion, and a teeth portion protruding from the yoke portion to the inside in the yoke portion radial direction,
The stator pieces are in contact with each other at surfaces formed by side surfaces in the yoke portion circumferential direction of the yoke portions of the stacked stator piece plates,
The stator piece plate is formed by stamping a material by pressing,
A method of manufacturing a motor stator having a divided structure in which when the stator piece plate is punched by press working, the tooth portion is punched at a speed higher than the yoke portion. An apparatus for manufacturing a motor stator having a split structure in which a plurality of stator pieces configured by laminating a plurality of stator piece plates are arranged in an annular shape,
The stator piece plate includes an arc-shaped yoke portion, and a teeth portion protruding from the yoke portion to the inside in the yoke portion radial direction,
The stator pieces are in contact with each other at surfaces formed by side surfaces in the yoke portion circumferential direction of the yoke portions of the stacked stator piece plates,
The manufacturing apparatus includes a mold for punching a material by press working to mold the stator piece plate,
The mold includes a first punch for punching a teeth portion of the stator piece plate, and a second punch for punching a yoke portion of the stator piece plate,
The first punch and the second punch are configured to reciprocate in the press direction by a crank motion,
The punching position for punching the material of the second punch is located closer to the bottom dead center in the crank motion than the punching position for punching the material of the first punch.
A device for manufacturing a motor stator having a split structure.

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