Laminated iron core, manufacturing method of laminated iron core, and die device

Abstract

To improve the space factor of a lamination core.SOLUTION: A lamination core includes a laminate that is constituted of a plurality of punched members stacked on one another, with punched members adjacent to each other in the lamination direction being caulked to be joined. Therein, a recess and a projection are formed by the caulking. The recess is formed in one surface side of each punched member. The projection is formed on the other surface side of each punched member. Further, in a plan view, a part of a side surface of the projection is positioned on an inner side of a side surface of the recess, or aligned with the side surface of the recess.SELECTED DRAWING: Figure 4C

Description

[Technical Field]

[0001] The disclosed embodiments relate to a laminated core, a method for manufacturing a laminated core, and a die apparatus. [Background technology]

[0002] For example, laminated cores that make up motor stators and rotors are manufactured by feeding a strip of metal plate into a die device, where it is punched in order at processing stations aligned along the feeding direction of the metal plate to form punched members of the desired shape.The resulting punched members are then stacked while being joined together by crimping, thereby producing a laminated core. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 4-325846 Summary of the Invention [Problem to be solved by the invention]

[0004] On the other hand, in the above-mentioned conventional technology, when the crimping of adjacent punched members is difficult to fit, the punched members may not be able to adhere to each other sufficiently, which may result in a decrease in the space factor of the laminated core.

[0005] One aspect of the embodiment has been made in view of the above, and aims to provide a laminated core, a manufacturing method for a laminated core, and a die device that can improve the space factor. [Means for solving the problem]

[0006] A laminated core according to one aspect of the embodiment includes a laminated body formed by stacking a plurality of punched members, with adjacent punched members joined together in the stacking direction by crimping. The crimping has a recess and a protrusion. The recess is formed on one surface of the punched member. The protrusion is formed on the other surface of the punched member. In a plan view, a portion of the side of the protrusion is located inside the side of the recess or is aligned with the side of the recess.

[0007] Furthermore, a manufacturing method of a laminated core according to one aspect of the embodiment includes a crimp forming step, a punching step, and a laminate forming step. The crimp forming step forms crimps in a strip-shaped metal plate. The punching step punches the metal plate to form a punched member with the crimp formed therein. The laminate forming step stacks a plurality of the punched members and joins adjacent punched members in the stacking direction by crimping to form a laminate. The crimp forming step also forms a recess on one surface of the metal plate using a punch, and forms a protrusion on the other surface of the metal plate using a die plate with a recess formed therein. Furthermore, in a plan view, a portion of the side of the protrusion is located inside the side of the recess or is aligned with the side of the recess.

[0008] In addition, a die apparatus according to one aspect of the present invention includes a crimp forming unit that forms crimps in a strip-shaped metal plate to join adjacent punched members in a stacking direction in a laminate. The crimp forming unit includes a punch and a die plate having a recess disposed opposite the punch. In addition, in a plan view, a portion of a side surface of the recess is located inside a side surface of the punch or is aligned with the side surface of the punch. [Effects of the Invention]

[0009] According to one aspect of the embodiment, the space factor of the laminated core can be improved. [Brief explanation of the drawings]

[0010] [Figure 1]FIG. 1 is a schematic diagram showing an example of a manufacturing apparatus for a laminated iron core according to an embodiment. [Figure 2] FIG. 2 is a perspective view showing an example of a laminated core according to the embodiment. [Figure 3A] FIG. 3A is a flowchart showing an example of the procedure of each manufacturing process executed by the stamping device according to the embodiment. [Figure 3B] FIG. 3B is a view for explaining an example of a caulking forming step according to the embodiment. [Figure 3C] FIG. 3C is a view for explaining an example of a punching step and a laminate forming step according to the embodiment. [Figure 3D] FIG. 3D is an enlarged cross-sectional view showing an example of a laminated core according to an embodiment. [Figure 4A] FIG. 4A is a plan view showing an example of caulking according to the embodiment. [Figure 4B] FIG. 4B is a cross-sectional view taken along line AA in FIG. 4A. [Figure 4C] FIG. 4C is a cross-sectional view taken along line BB in FIG. 4A. [Figure 4D] FIG. 4D is a diagram showing an example of the positional relationship in plan view between the side surface of the recessed portion and the side surface of the protruding portion at the corner portion of the caulking according to the embodiment. [Figure 5A] FIG. 5A is an enlarged cross-sectional view of a corner portion of a caulking according to a first modification of the embodiment. [Figure 5B] FIG. 5B is a diagram showing an example of the positional relationship in a plan view between a side surface of a recess and a side surface of a protrusion at a corner portion of a caulking according to the first modification of the embodiment. [Figure 6A] FIG. 6A is a plan view showing an example of caulking according to Modification 2 of the embodiment. [Figure 6B] FIG. 6B is a diagram showing an example of the positional relationship in plan view between the side surface of the recess and the side surface of the protrusion in the large curvature portion of the caulking according to the second modification of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, a laminated core, a manufacturing method of a laminated core, and a die device disclosed in the present application will be described with reference to the accompanying drawings. Note that the present disclosure is not limited to the following embodiments.

[0012] It should also be noted that the drawings are schematic and that the dimensional relationships and ratios of elements may differ from reality. Furthermore, the drawings may contain parts whose dimensional relationships and ratios differ from one another.

[0013] Furthermore, in the following embodiments, expressions such as "constant," "orthogonal," "perpendicular," or "parallel" may be used, but these expressions do not necessarily mean "constant," "orthogonal," "perpendicular," or "parallel" in the strict sense. In other words, the above expressions allow for deviations due to, for example, manufacturing precision, installation precision, etc.

[0014] For example, laminated iron cores that make up the stators and rotors of motors are made by feeding a strip of metal plate into a die device in sequence, and then punching it out in succession at processing stations positioned in a row along the feeding direction of the metal plate to form punched parts of the desired shape.

[0015] In addition, in this processing station, crimps are formed at predetermined positions by half-blanking. The obtained punched members are then stacked while being joined together by crimping, thereby manufacturing a laminated core.

[0016] On the other hand, in the above-mentioned conventional technology, when the crimping portions of adjacent punched members are difficult to fit together, the punched members may not be able to adhere closely to each other. One of the reasons for this is that when the protruding portion of the crimping portion formed on one punched member is fitted into the recessed portion of the crimping portion formed on the adjacent punched member, even if the protruding portion of the crimping portion is deformed, it does not fit into the recessed portion.

[0017] This creates gaps between adjacent punched members, which may reduce the space factor of the laminated core.

[0018] Therefore, there is a need to develop a technology that can overcome the above problems and improve the space factor of laminated cores.

[0019] <Manufacturing equipment> First, a laminated iron core manufacturing apparatus 100 according to an embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic diagram showing an example of a laminated iron core manufacturing apparatus 100 according to an embodiment. The manufacturing apparatus 100 according to an embodiment is configured to manufacture a laminate of a punched member W (see Fig. 2) from a strip-shaped electromagnetic steel sheet MS.

[0020] In order to make the explanation easier to understand, the drawings referred to below may show an orthogonal coordinate system in which the X-axis direction, Y-axis direction, and Z-axis direction, which are perpendicular to each other, are defined, the positive Z-axis direction is the vertically upward direction, the positive X-axis direction is the forward feed direction of the electromagnetic steel sheet MS, and the Y-axis is the width direction of the electromagnetic steel sheet MS.

[0021] 1, the manufacturing apparatus 100 includes an uncoiler 110, a feed device 120, a press working device 130, and a controller Ctr (control unit). The press working device 130 is an example of a die device.

[0022] The uncoiler 110 is configured to rotatably hold the coil material 111. The coil material 111 is an electromagnetic steel sheet MS wound in a coil shape (spiral shape). The electromagnetic steel sheet MS is an example of a metal sheet.

[0023] The feed-out device 120 includes a pair of rollers 121, 122 that sandwich the electromagnetic steel sheet MS from above and below. The pair of rollers 121, 122 are configured to rotate and stop based on command signals from the controller Ctr, and to intermittently and sequentially feed out the electromagnetic steel sheet MS toward the press processing device 130 (hereinafter also referred to as "sequential feeding"). In other words, the pair of rollers 121, 122 function as a conveying means for conveying the electromagnetic steel sheet MS.

[0024] The press working device 130 is configured to operate based on an instruction signal from the controller Ctr. The press working device 130, for example, operates a plurality of punches (not shown) to sequentially perform press working (for example, punching or half-punching) on ​​the electromagnetic steel sheets MS delivered by the delivery device 120.

[0025] As a result, the press processing device 130 is configured to form a plurality of punched members W (see FIG. 2). Moreover, the press processing device 130 according to the embodiment is configured to sequentially stack the plurality of punched members W obtained by punching to form a laminate.

[0026] The press working device 130 includes a lower die 140, an upper die 150, and a press machine 160. The lower die 140 is positioned below the electromagnetic steel sheet MS being fed forward and supports the electromagnetic steel sheet MS from below. The upper die 150 is positioned above the electromagnetic steel sheet MS being fed forward and moves up and down to press the electromagnetic steel sheet MS.

[0027] The press 160 is located above the upper die 150. The piston of the press 160 is connected to a punch holder (not shown) that holds a plurality of punches provided in the upper die 150, and operates based on a command signal from the controller Ctr. When the press 160 operates, the piston expands and contracts, causing the entire upper die 150 to move up and down.

[0028] The controller Ctr is configured to generate instruction signals for operating the feeding device 120 and the press working device 130 based on, for example, a program recorded on a recording medium (not shown) or an operation input from an operator. The controller Ctr is configured to transmit these instruction signals to the feeding device 120 and the press working device 130, respectively.

[0029] <Laminated iron core> Next, the configuration of the laminated core 1 according to the embodiment will be described with reference to Fig. 2. Fig. 2 is a perspective view showing an example of the laminated core 1 according to the embodiment. The laminated core 1 is, for example, a stator laminated core, and is part of a stator.

[0030] The stator is a laminated core 1 to which windings are attached. A motor is formed by combining the stator with a rotor.

[0031] 2, the laminated core 1 has a cylindrical shape. That is, a through hole 1a (center hole) extending along the central axis Ax is provided in the central portion of the laminated core 1. A rotor can be placed inside the through hole 1a.

[0032] The laminated core 1 is a laminated body formed by stacking a plurality of punched members W. The punched members W are plate-like bodies obtained by punching out strip-shaped electromagnetic steel sheets MS (see FIG. 1) into a predetermined shape.

[0033] The laminated core 1 according to the embodiment may be constructed by so-called "rolling." This "rolling" refers to stacking a plurality of punched members W while shifting the angles between the punched members W relative to each other. The rolling is performed mainly for the purpose of offsetting the thickness deviation of the laminated core 1. The rolling angle may be set to any value.

[0034] The laminated core 1 includes a yoke portion 2, a plurality of teeth 3, and a plurality of crimped portions 4. The yoke portion 2 has an annular shape and extends to surround the central axis Ax. The radial width, inner diameter, outer diameter, and thickness of the yoke portion 2 can each be set to various values ​​depending on the application and performance of the motor.

[0035] Each tooth 3 extends radially from the inner edge of the yoke 2 toward the central axis Ax. That is, each tooth 3 protrudes from the inner edge of the yoke 2 toward the central axis Ax.

[0036] For example, in the example of Fig. 2, twelve teeth 3 are formed integrally with the yoke part 2. The teeth 3 are arranged at approximately equal intervals in the circumferential direction of the yoke part 2. Slots 5 are defined between adjacent teeth 3, which function as spaces for arranging windings (not shown).

[0037] The crimping portions 4 may be provided on the yoke portion 2, on each tooth portion 3, or on both the yoke portion 2 and each tooth portion 3. Adjacent punched members W in the height direction are fastened together by the crimping portions 4.

[0038] Specifically, the crimped portion 4 includes crimps 10 (see FIG. 3D) formed in a punched member W that constitutes a layer other than the bottommost layer of the laminated core 1, and a through hole W0a (see FIG. 3D) formed in a punched member W0 (see FIG. 3D) that constitutes the bottommost layer of the laminated core 1. Details of the crimped portion 4 will be described later.

[0039] <Manufacturing process> Next, the manufacturing process of the laminated core 1 by the stamping device 130 according to the embodiment will be described with reference to Figures 3A to 3D. Figure 3A is a flowchart showing an example of the procedure of each manufacturing process performed by the stamping device 130 according to the embodiment.

[0040] Each manufacturing process described below is performed by controlling the feed device 120 (see FIG. 1) and other devices to feed the electromagnetic steel sheet MS (see FIG. 1) into the press processing device 130 (see FIG. 1) in a predetermined direction.

[0041] 3A, the controller Ctr (see FIG. 1) first controls the press working device 130 to lower the upper die 150 (see FIG. 1) so that the electromagnetic steel sheet MS is sandwiched between the upper die 150 and the lower die 140 (see FIG. 1), and press working is performed on the electromagnetic steel sheet MS (step S101). As a result, the yoke portion 2, teeth portion 3, and the like as shown in FIG. 2 are formed in the punched member W.

[0042] In parallel with the processing of step S101, the controller Ctr controls the stamping device 130 to lower the upper die 150 so that the electromagnetic steel sheet MS is sandwiched between the upper die 150 and the lower die 140, thereby forming the caulking 10 in the electromagnetic steel sheet MS (step S102). Details of this caulking forming step will be described with reference to FIG. 3B.

[0043] 3B is a diagram for explaining an example of a caulking step according to the embodiment. As shown in FIG. 3B, the stamping device 130 has a caulking forming unit 131 that forms the caulking 10 in the electromagnetic steel sheet MS.

[0044] In the caulking forming section 131, a recess 142 is provided in a die plate 141 of a lower die 140, and a punch 151 is provided in an upper die 150. Further, a stripper 152 is provided in the upper die 150 of the caulking forming section 131 so that the punch 151 can be removed.

[0045] The die plate 141, together with a punch 151 provided in the upper die 150, functions to form a punched member W (see FIG. 3D). The die plate 141 is supported by, for example, a base (not shown) and a die holder (not shown). The recess 142 provided in the die plate 141 has a side surface 142a that is perpendicular to the lower surface of the electromagnetic steel sheet MS.

[0046] The punch 151 has a function of performing half-punching at a predetermined position on the electromagnetic steel sheet MS located in the caulking forming portion 131. The punch 151 is provided at a position opposite to the recess 142 of the die plate 141.

[0047] The punch 151 has a side surface 151a that is perpendicular to the upper surface of the electromagnetic steel sheet MS. The punch 151 is supported by a punch holder (not shown) that is positioned above the stripper 152, for example.

[0048] The stripper 152 has the function of clamping the electromagnetic steel sheet MS between itself and the die plate 141 when the electromagnetic steel sheet MS is subjected to half-punching processing with the punch 151 provided on the upper die 150, and the function of removing the electromagnetic steel sheet MS that has bitten into the punch 151 from the punch 151 after half-punching processing.

[0049] The stripper 152 is supported so as to be movable up and down relative to a punch holder (not shown) located above the stripper 152, for example.

[0050] As shown in Fig. 3B, the controller Ctr (see Fig. 1) lowers the upper die 150 to sandwich the electromagnetic steel sheet MS between the stripper 152 and the die plate 141. Then, the controller Ctr lowers the punch 151 so that the lower end of the punch 151 reaches the middle of the electromagnetic steel sheet MS, thereby forming a caulking 10 in the electromagnetic steel sheet MS.

[0051] The crimp 10 formed on the electromagnetic steel sheet MS has a recess 11 and a protrusion 12. The recess 11 is formed on one surface side (the upper surface side in the figure) of the electromagnetic steel sheet MS by a punch 151. The protrusion 12 is formed on the other surface side (the lower surface side in the figure) of the electromagnetic steel sheet MS by a depression 142 in a die plate 141.

[0052] Returning to the description of Fig. 3A, after the processes of step S101 and step S102, the controller Ctr controls the stamping device 130 to lower the upper die 150 so that the electromagnetic steel sheet MS is sandwiched between the upper die 150 and the lower die 140, and the electromagnetic steel sheet MS is punched out to form a punched member W (step S103).

[0053] After this punching step, the controller Ctr controls the press device 130 to stack the punched members W to form a laminate that will become the laminated core 1 (step S104). Details of the punching step and the laminate formation step will be described with reference to FIGS. 3C and 3D.

[0054] Fig. 3C is a diagram illustrating an example of a punching step and a laminate forming step according to the embodiment, and Fig. 3D is an enlarged cross-sectional view showing an example of a laminated core 1 according to the embodiment. As shown in Fig. 3C, the press working device 130 has a punching section 132 that punches out the electromagnetic steel sheets MS to form the laminated core 1.

[0055] In the punching section 132, a through hole 143 is provided in a die plate 141 of a lower die 140, and a punch 153 is provided in an upper die 150. In addition, a stripper 152 is provided in the upper die 150 of the punching section 132 so that the punch 153 can be removed.

[0056] An elevator cylinder 171 that is controlled to be able to move up and down is provided below the through hole 143 provided in the die plate 141. A transport table 172 that transports the laminated core 1 to the outside is provided below the lower die 140. On the opposite side of the transport table 172 with respect to the elevator cylinder 171, a pusher cylinder 173 that is controlled to be able to reciprocate horizontally is provided.

[0057] As shown in Fig. 3C, the controller Ctr (see Fig. 1) lowers the upper die 150 to sandwich the electromagnetic steel sheet MS between the stripper 152 and the die plate 141. Then, the controller Ctr lowers the punch 151 so that the lower end of the punch 151 reaches a position below the electromagnetic steel sheet MS, thereby punching out the electromagnetic steel sheet MS to form a punched member W (see Fig. 3D).

[0058] Furthermore, the controller Ctr appropriately adjusts the height of the lift cylinder 171 inside the through-hole 143 and moves the punch 151 downward so that the punching member W is placed on the lift cylinder 171 .

[0059] The controller Ctr then repeats the process of forming the punched members W and the process of placing the punched members W on the lifting cylinder 171, thereby forming a stack of the punched members W on the lifting cylinder 171.

[0060] When the laminated body of the punched members W reaches a predetermined dimension and the laminated core 1 is formed, the controller Ctr carries out the laminated core 1 from the through-hole 143. Specifically, first, the controller Ctr lowers the lifting cylinder 171 so that the upper surface of the lifting cylinder 171 is approximately flush with the upper surface of the transfer table 172.

[0061] Next, the controller Ctr causes the pusher cylinder 173 to push out the laminated core 1 on the lifting cylinder 171 onto the transfer table 172. As a result, the laminated core 1 formed inside the through-hole 143 of the lower mold 140 is carried out onto the transfer table 172.

[0062] Furthermore, when forming a stack of punched members W on the lifting cylinder 171, the crimps 10 of adjacent punched members W fit together. Specifically, as shown in Fig. 3D, a recess 11 (see Fig. 3B) provided in the crimp 10 of one punched member W fits together with a protrusion 12 (see Fig. 3B) provided in the crimp 10 of the other punched member W. This allows the adjacent punched members W to be joined together.

[0063] Furthermore, a through hole W0a is formed in the punched member W0 that forms the bottom layer of the laminated core 1. When laminated cores 1 are successively manufactured, this through hole W0a has the function of preventing a subsequently formed punched member W from being fastened by caulking 10 to an already manufactured laminated core 1.

[0064] In the example of Figure 3C, an example is shown in which the punching process and the laminate formation process are performed consecutively within the press processing device 130, but the present disclosure is not limited to such an example, and the multiple punched members W formed in the punching process may be made into a laminate at a location separate from the press processing device 130.

[0065] Returning to the description of Figure 3A, following the processing of step S104, the controller Ctr determines whether the manufacturing process of the laminated core 1 has been completed (step S105). If the manufacturing process of the laminated core 1 has been completed (step S105, Yes), the series of processes ends. On the other hand, if the manufacturing process of the laminated core 1 has not been completed (step S105, No), the process returns to steps S101 and S102.

[0066] <Crimping details> Next, details of the caulking 10 formed in the punched member W according to the embodiment will be described with reference to Figures 4A to 4D. Figure 4A is a plan view showing an example of the caulking 10 according to the embodiment.

[0067] 4A, the crimping member 10 according to the embodiment has a rectangular shape in a plan view and includes four straight line portions 21 and four corner portions 22. The straight line portions 21 correspond to the sides of the rectangle, and the corner portions 22 correspond to the corners of the rectangle. In the crimping member 10 according to the embodiment, the corner portions 22 have an R-shape.

[0068] 4B is a cross-sectional view taken along line AA in FIG. 4A, and shows the cross-sectional shape of straight portion 21 of caulking 10. As shown in FIG. 3B and other figures, caulking 10 has recessed portion 11 and protruding portion 12.

[0069] 4B, the recess 11 has a side surface 11a, and the protrusion 12 has a side surface 12a. The side surface 11a of the recess 11 is approximately perpendicular to the surface Wa of the punching member W on which the recess 11 is provided. This is because the side surface 151a (see FIG. 3B) of the punch 151 (see FIG. 3B) that forms the side surface 11a of the recess 11 is approximately perpendicular to the surface Wa.

[0070] Furthermore, the side surface 12a of the protrusion 12 is approximately perpendicular to the surface Wb of the punching member W on which the protrusion 12 is provided. This is because the side surface 142a (see FIG. 3B) of the depression 142 (see FIG. 3B) that forms the side surface 12a of the protrusion 12 is approximately perpendicular to the surface Wb.

[0071] In this way, by forming the side surfaces 11a of the recessed portions 11 and the side surfaces 12a of the protruding portions 12 perpendicular to the surfaces Wa and Wb of the punched member W, respectively, it is possible to improve the adhesion between the side surfaces 11a and 12a when adjacent crimps 10 are fitted together. Therefore, according to the embodiment, it is possible to improve the crimp strength.

[0072] 4B, in the embodiment, in the linear portion 21 of the crimp 10, the side surface 12a of the convex portion 12 is positioned outside the side surface 11a of the concave portion 11. In this disclosure, the term "outside" refers to the side away from the inside of the crimp 10 in a plan view, and the term "inside" refers to the side closer to the inside of the crimp 10 in a plan view.

[0073] In this way, in the crimp 10 according to the embodiment, the side surface 12a of the protrusion 12 is positioned outside the side surface 11a of the recess 11, so that when adjacent crimps 10 fit together, the protrusion 12 fits so as to press the recess 11 outward. Therefore, according to the embodiment, the crimp strength can be improved.

[0074] On the other hand, if the side surface 12a of the protrusion 12 is positioned outside the side surface 11a of the recess 11 around the entire circumference of the crimp 10, there will be no place for the deformed portion of the protrusion 12 to escape when it is fitted in. As a result, the protrusion 12 cannot fit completely inside the recess 11, and there is a risk of gaps being formed between adjacent punched members W.

[0075] Therefore, in the embodiment, in a part of the crimp 10, the side surface 12a of the protrusion 12 is positioned more inward than the side surface 11a of the recess 11. For example, in the embodiment, as shown in Figures 4C and 4D, in a corner portion 22 of the crimp 10, the side surface 12a of the protrusion 12 is positioned more inward than the side surface 11a of the recess 11.

[0076] Fig. 4C is a cross-sectional view taken along line BB in Fig. 4A, illustrating the cross-sectional shape of corner portion 22 of crimping portion 10. Fig. 4D is a diagram illustrating an example of the positional relationship in a plan view between side surface 11a of recessed portion 11 and side surface 12a of protruding portion 12 at corner portion 22 of crimping portion 10 according to the embodiment.

[0077] In this way, by positioning the side surface 12a of the convex portion 12 more inward than the side surface 11a of the recessed portion 11 in part of the crimp 10, a place can be secured for the deformed portion of the convex portion 12 to escape to when the convex portion 12 fits into the recessed portion 11.

[0078] Therefore, according to the embodiment, it is possible to prevent gaps from being formed between the adjacent punched members W, and therefore the space factor of the laminated core 1 can be improved.

[0079] Furthermore, in the caulking 10 of the embodiment, the location where the side surface 12a of the protrusion 12 is positioned more inward than the side surface 11a of the recess 11 may be the corner portion 22. In this way, by providing a place to escape to the corner portion 22 where the deformed parts of the linear portions 21 of the two sides gather, it is possible to further prevent gaps from being formed between adjacent punched members W.

[0080] Therefore, according to the embodiment, the space factor of the laminated core 1 can be further improved.

[0081] As a means for forming the caulking 10 according to the embodiment, for example, in a plan view, a part of the side surface 142a of the recess 142 of the die plate 141 (for example, the corner portion 22) is positioned more inward than the side surface 151a of the punch 151. Then, the remaining part of the side surface 142a of the recess 142 of the die plate 141 (for example, the straight portion 21) is preferably positioned more outward than the side surface 151a of the punch 151.

[0082] 4A to 4D show an example in which the side surface 12a of the protrusion 12 is positioned more inward than the side surface 11a of the recess 11 at the corner portion 22 of the crimp 10, but the present disclosure is not limited to such an example. For example, the side surface 12a of the protrusion 12 may be positioned more inward than the side surface 11a of the recess 11 at a part of the linear portion 21 of the crimp 10.

[0083] This also makes it possible to prevent gaps from being formed between adjacent punched members W, thereby improving the space factor of the laminated core 1.

[0084] <Variation 1> Next, various modified examples of the crimp 10 will be described. Fig. 5A is an enlarged cross-sectional view of a corner portion 22 of the crimp 10 according to the first modified example of the embodiment. Fig. 5B is a diagram showing an example of the positional relationship in a plan view between a side surface 11a of the recess 11 and a side surface 12a of the protrusion 12 at the corner portion 22 of the crimp 10 according to the first modified example of the embodiment.

[0085] Although not shown in Figures 5A and 5B, in this variant example 1, as in the above embodiment, the side surface 12a of the convex portion 12 is positioned outside the side surface 11a of the concave portion 11 in the straight portion 21 of the crimp 10 (see Figure 4A).

[0086] In the first modification, as shown in FIGS. 5A and 5B, in a part of crimp 10 (here, corner portion 22 of crimp 10), side surface 12a of protrusion 12 and side surface 11a of recess 11 are aligned in a plan view.

[0087] This also makes it possible to prevent gaps from being formed between adjacent punched members W, thereby improving the space factor of the laminated core 1.

[0088] 5A and 5B show an example in which the positions of the side surface 12a of the protrusion 12 and the side surface 11a of the recess 11 are aligned at the corner portion 22 of the crimp 10, but the present disclosure is not limited to such an example. For example, the positions of the side surface 12a of the protrusion 12 and the side surface 11a of the recess 11 may be aligned at a portion of the linear portion 21 of the crimp 10.

[0089] This also makes it possible to prevent gaps from being formed between adjacent punched members W, thereby improving the space factor of the laminated core 1.

[0090] As a means for forming the caulking 10 according to the first modification, for example, a part of the side surface 142a of the recess 142 of the die plate 141 (for example, the corner portion 22) is aligned with the side surface 151a of the punch 151 in a plan view. Then, the remaining part of the side surface 142a of the recess 142 of the die plate 141 (for example, the straight portion 21) is preferably positioned outward from the side surface 151a of the punch 151.

[0091] <Variation 2> 6A is a plan view showing an example of a crimp 10 according to Modification 2 of the embodiment. As shown in Fig. 6A, the crimp 10 according to Modification 2 has an elliptical shape in a plan view and includes two large curvature portions 31. The large curvature portions 31 are the portions of the elliptical crimp 10 with the largest curvature.

[0092] 6B is a diagram showing an example of the positional relationship in a plan view between the side surface 11a of the recess 11 and the side surface 12a of the protrusion 12 in the large curvature portion 31 of the crimp 10 according to Modification 2 of the embodiment. As shown in FIG. 6B, in Modification 2, in a part of the crimp 10 (here, the large curvature portion 31 of the crimp 10), the side surface 12a of the protrusion 12 is located more inward than the side surface 11a of the recess 11.

[0093] In addition, in this modification 2, the side surface 12a of the protrusion 12 is positioned outside the side surface 11a of the recess 11 in the remaining portion of the caulking 10 (for example, a portion other than the large curvature portion 31).

[0094] This also makes it possible to position the side surface 12a of the convex portion 12 more inward than the side surface 11a of the concave portion 11 in part of the crimp 10, thereby ensuring a place for the deformed portion of the convex portion 12 to escape when the convex portion 12 fits into the concave portion 11.

[0095] Therefore, according to the second modification, it is possible to prevent gaps from being formed between the adjacent punched members W, and therefore it is possible to improve the space factor of the laminated core 1.

[0096] Furthermore, in the caulking 10 of the second modification, the portion where the side surface 12a of the protrusion 12 is positioned more inward than the side surface 11a of the recess 11 may be the large curvature portion 31. In this way, by ensuring a place to escape to the large curvature portion 31 where the deformed portions gather in the area of ​​small curvature, it is possible to further prevent gaps from being formed between adjacent punched members W.

[0097] Therefore, according to the second modification, the space factor of the laminated core 1 can be further improved.

[0098] 6B shows an example in which the side surface 12a of the protrusion 12 is positioned more inward than the side surface 11a of the recess 11 in the large curvature portion 31 of the crimp 10, but the present disclosure is not limited to this example. For example, the side surface 12a of the protrusion 12 may be positioned more inward than the side surface 11a of the recess 11 in a part of the crimp 10 other than the large curvature portion 31.

[0099] This also makes it possible to prevent gaps from being formed between adjacent punched members W, thereby improving the space factor of the laminated core 1.

[0100] In addition, in the example of Figure 6B, an example is shown in which the side surface 12a of the convex portion 12 is positioned more inward than the side surface 11a of the concave portion 11 in the large curvature portion 31 of the crimping portion 10, but the positions of the side surface 12a of the convex portion 12 and the side surface 11a of the concave portion 11 may be aligned in the large curvature portion 31.

[0101] This also makes it possible to prevent gaps from being formed between adjacent punched members W, thereby improving the space factor of the laminated core 1.

[0102] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present invention. For example, in the above-described embodiments, examples have been shown in which the crimp 10 has a rectangular or elliptical shape in plan view, but the present disclosure is not limited to such examples, and the crimp 10 may have other shapes in plan view.

[0103] Furthermore, in the above embodiment, an example has been shown in which the side surface 11a of the recess 11 and the side surface 151a of the punch 151 are approximately perpendicular to the surface Wa of the punching member W, and the side surface 12a of the protrusion 12 and the side surface 142a of the depression 142 are approximately perpendicular to the surface Wb of the punching member W. However, the present disclosure is not limited to such an example, and at least one of the side surface 11a of the recess 11 (i.e., the side surface 151a of the punch 151) and the side surface 12a of the protrusion 12 (i.e., the side surface 142a of the depression 142) may have a tapered shape.

[0104] As described above, the laminated core 1 according to the embodiment includes a laminated body formed by stacking a plurality of punched members W, with adjacent punched members W in the stacking direction being joined by crimps 10. The crimps 10 have recesses 11 and protrusions 12. The recesses 11 are formed on one surface Wa of the punched members W. The protrusions 12 are formed on the other surface Wb of the punched members W. In plan view, a portion of the side surface 12a of the protrusions 12 is located inside the side surface 11a of the recesses 11 or is aligned with the side surface 11a of the recesses 11. This allows the space factor of the laminated core 1 to be improved.

[0105] In the laminated core 1 according to the embodiment, the crimps 10 are rectangular in plan view. At the corners 22 of the crimps 10, part of the side surfaces 12a of the protrusions 12 is located inside the side surfaces 11a of the recesses 11, or is aligned with the side surfaces 11a of the recesses 11. This allows the space factor of the laminated core 1 to be further improved.

[0106] Furthermore, in the laminated core 1 according to the embodiment, the crimps 10 are elliptical in plan view. Furthermore, in the portion of the crimp 10 with the greatest curvature (large curvature portion 31), part of the side surface 12a of the protrusion 12 is located inside the side surface 11a of the recess 11, or is aligned with the side surface 11a of the recess 11. This allows the space factor of the laminated core 1 to be further improved.

[0107] Furthermore, in the laminated core 1 according to the embodiment, in plan view, part of the side surface 12a of the protrusion 12 is located inside the side surface 11a of the recess 11. This allows the space factor of the laminated core 1 to be further improved.

[0108] Moreover, the manufacturing method of the laminated core 1 according to the embodiment includes a crimp forming step (step S102), a punching step (step S103), and a laminate forming step (step S104). The crimp forming step (step S102) forms crimps 10 in a strip-shaped metal plate (electromagnetic steel plate MS). The punching step (step S103) punches the metal plate (electromagnetic steel plate MS) to form a punched member W on which the crimps 10 are formed. The laminate forming step (step S104) stacks a plurality of punched members W and joins adjacent punched members W in the stacking direction with the crimps 10 to form a laminate. Furthermore, the crimp forming step (step S102) forms recesses 11 on one surface of the metal plate (electromagnetic steel plate MS) using a punch 151. In addition, in the crimping process (step S102), protrusions 12 are formed on the other surface of the metal plate (electromagnetic steel sheet MS) using a die plate 141 in which recesses 142 are formed. In addition, in a plan view, part of the side surface 12a of protrusion 12 is located inside side surface 11a of recess 11 or is aligned with side surface 11a of recess 11. This allows the space factor of laminated core 1 to be improved.

[0109] Moreover, the die device (pressing device 130) according to the embodiment includes a caulking forming unit 131 that forms caulkings 10 in a strip-shaped metal plate (electromagnetic steel sheet MS) to join adjacent punched members W in the stacking direction in the laminate. The caulking forming unit 131 includes a punch 151 and a die plate 141. The die plate 141 has a recess 142 that is disposed opposite the punch 151. In addition, in a plan view, a portion of a side surface 142a of the recess 142 is located inside the side surface 151a of the punch 151 or is aligned with the side surface 151a of the punch 151. This allows the space factor of the laminated core 1 to be improved.

[0110] Further advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. [Explanation of symbols]

[0111] 1 Laminated core 10 Crimping 11 Recess 11a Side 12 Convex part 12a side 21 Straight section 22 Corner section 31 Large curvature section 100 Manufacturing equipment 130 Press processing equipment (an example of a die device) 131 Caulking forming part 140 Lower mold 141 Die Plate 142 depression 142a side 150 upper mold 151 Punch 151a side MS: Electromagnetic steel sheet (an example of a metal sheet) W punched material Wa, Wb surface

Claims

1. A laminate is provided in which a plurality of punched members are stacked, and the punched members adjacent to each other in the stacking direction are joined by crimping, The crimping is In plan view, the rectangular shape is made up of four straight line portions and four rounded corner portions, a recess formed on one surface side of the punching member; a protrusion formed on the other surface side of the punching member; and In a plan view, a side surface of the convex portion in the linear portion of the crimp provided in the punched member before the laminate is formed is located outside a side surface of the concave portion, In a plan view, the side surface of the convex portion at the corner portion of the crimp provided on the punched member before forming the laminate is located inside the side surface of the concave portion or is aligned with the side surface of the concave portion. Laminated iron core.

2. In a plan view, a part of a side surface of the protrusion is located inside a side surface of the recess. The laminated core according to claim 1 .

3. a crimp forming step of forming a rectangular crimp on the belt-shaped metal plate, the rectangular crimp having four straight line portions and four rounded corner portions in a plan view; a punching step of punching the metal plate to form a punched member on which the caulking is formed; a stack forming step of stacking a plurality of the punched members and joining adjacent punched members in the stacking direction by the crimping to form a stack; Including, The caulking step includes forming a recess on one surface of the metal plate by a punch and forming a protrusion on the other surface of the metal plate by a die plate having a recess formed therein; In a plan view, a side surface of the convex portion in the linear portion of the crimp provided in the punched member before the laminate is formed is located outside a side surface of the concave portion, In a plan view, the side surface of the convex portion at the corner portion of the crimp provided on the punched member before forming the laminate is located inside the side surface of the concave portion or is aligned with the side surface of the concave portion. Manufacturing method of laminated core.

4. a crimp forming portion that joins adjacent punched members in the stacking direction in the laminate and forms a rectangular crimp, in a plan view, on the band-shaped metal plate, the crimp having four straight portions and four R-shaped corner portions; The crimp forming portion is Punch and a die plate having a recess disposed opposite the punch; Equipped with In a plan view, a side surface of the depression corresponding to the linear portion of the crimp is located outside a side surface of the punch, In a plan view, a side surface of the recess corresponding to the corner portion of the crimp is located inside the side surface of the punch or is aligned with the side surface of the punch. Mold equipment.

Images