Laminated core manufacturing apparatus and laminated core manufacturing method

Abstract

Disclosed are a laminated core manufacturing apparatus and a laminated core manufacturing method. The laminated core manufacturing apparatus according to the present invention comprises: a liftable upper mold; a piercing punch which is provided to the upper mold to form the outer circumferential surface of a first lamina having a first radius, includes, at the distance of the first radius, punch tips having an arc-shaped inner end portion and distributed and formed along the circumferential direction, and is capable of punching, at a selective time, a strip intermittently transferred so as to form the first lamina; a blanking punch which is provided in the upper mold, is capable of punching the strip to form the first lamina and a second lamina having an outer circumferential surface of a second radius that is larger than the first radius, has a lower end portion of the second radius, and is spaced apart from the piercing punch by a predetermined distance; a lower mold which faces the upper mold and is provided below the upper mold; and a stacking die which has a blanking die facing the blanking punch and provided in the lower mold, and in which the first lamina and the second lamina are stacked.

Description

Laminated core manufacturing device and laminated core manufacturing method

[0001] The present invention relates to a laminated core manufacturing device and a laminated core manufacturing method, and more particularly, to a laminated core manufacturing device and a laminated core manufacturing method capable of forming laminae having different outer diameters and manufacturing a laminated core having the laminae.

[0002] In general, a laminated core refers to a core having a laminated structure manufactured by integrating multiple thin plates, or lamina, and for example, refers to a laminated structure in which multiple laminas formed by punching a metal strip are overlapped and integrated.

[0003] These laminated cores are used as cores for various devices such as rotating machines such as generators and motors, transformers, and ignition systems, and various methods for manufacturing them are known.

[0004] Known methods for manufacturing the above-described laminated core, i.e., methods for manufacturing the laminated core by laminating / integrating the above-described lamina, include a tab fixing method using continuous bonding of interlock tabs, i.e., protrusions having an embossed shape (also called caulking protrusions), a welding fixing method using welding, e.g., laser welding, and a rivet fixing method.

[0005] Another example of manufacturing the aforementioned laminated core is a technology for bonding laminae together by adhesive means, i.e., an adhesive-type laminated core manufacturing technology. For example, an invention is disclosed in Japanese Patent Laid-Open No. 2009-297758, which involves applying an adhesive to the surface of a metal strip supplied to a device (mold) for manufacturing a laminated core and then punching out the metal strip to manufacture a laminated core.

[0006] Recently, a progressive die type laminated core manufacturing device has been used to manufacture the above-described laminated core. Fig. 1 is a drawing showing an example of a laminae and a laminated core, in which a plurality of laminae (L) are combined to form a laminated core (C). Of course, the shape of the laminae is not limited to the example of Fig. 1 and may vary.

[0007] Meanwhile, due to the recent increase in motor size and advancement in motor technology, the shape of motor cores is becoming increasingly complex and diverse. In particular, when a laminated core manufacturing device, such as two or more progressive molds, is used to manufacture motor cores with complex shapes, a separate assembly process is required and the mold manufacturing cost increases.

[0008] The purpose of the present invention is to provide a device and method for manufacturing a laminated core having laminae with different outer diameters.

[0009] One aspect of the present invention comprises: a lifting upper mold; a piercing punch, which is provided on the upper mold to form an outer surface of a first lamina having a first radius, and which includes punch tips having an inner end in an arc shape at a distance of the first radius and which are formed in a circumferential direction in a split manner, and which is capable of selectively punching a strip that is intermittently conveyed to form the first lamina; a blanking punch, which is provided on the upper mold and is capable of punching the strip to form the first lamina and a second lamina having a second radius, the outer surface of which has a radius greater than the first radius, and which has a lower end of the second radius and is spaced apart from the piercing punch by a predetermined distance; a lower mold, which faces the upper mold and is provided on a lower side of the upper mold; And, a laminated core manufacturing device is provided, which has a blanking die provided on the lower mold and facing the blanking punch, and includes a laminated die in which the first lamina and the second lamina are stacked.

[0010] The blanking punch includes punch grooves formed along the circumferential direction on the outer surface of the lower portion of the blanking punch; the distance from the center of the blanking punch to the punch grooves may be equal to the first radius or may be smaller or larger than the first radius. When the distance from the center of the blanking punch to the punch grooves is larger than the first radius, protrusions may be formed on the outer surface of the first lamina.

[0011] And the blanking die may include die projections formed along the circumferential direction on the inner surface of the blanking die and facing the punch grooves. By lowering the blanking punch, the punch groove can be engaged with the die projection and formed. In other words, the punch groove and the die projection can be manufactured to have the same size and shape.

[0012] Another aspect of the present invention provides a method for manufacturing a laminated core using the above-described laminated core manufacturing apparatus. The method for manufacturing a laminated core includes a blanking process in which the strip is punched with the blanking punch to first form one of the first lamina and the second lamina and then form the other lamina so that the first lamina and the second lamina are laminated inside the laminated die.

[0013] At the entrance side of the blanking punch, a piercing process by the piercing punch can be performed at a selective time, i.e., at a time when formation of the first lamina is required.

[0014] According to the present invention, since laminae having different outer diameters can be manufactured together in a single row using a single progressive mold, the number of laminated core manufacturing devices can be reduced, thereby reducing the mold manufacturing cost, and since a separate assembly process is unnecessary, the core manufacturing process can be reduced, labor costs can be reduced, and productivity can be improved.

[0015] The features and advantages of the present invention may be better understood by reference to the following detailed description of embodiments of the present invention, together with the drawings, of which:

[0016] Fig. 1 is a perspective view showing an example of a laminar and a laminated core;

[0017] FIG. 2 is a schematic drawing showing one embodiment of a laminated core manufacturing device according to the present invention;

[0018] FIG. 3 is a drawing illustrating a state in which laminae are laminated on a laminated die of the laminated core manufacturing device illustrated in FIG. 2;

[0019] FIG. 4 is a plan view of a first lamina and a second lamina that can be manufactured by the laminated core manufacturing device illustrated in FIG. 2, and a state in which the first lamina and the second lamina are overlapped;

[0020] Fig. 5 is a drawing illustrating a processing layout of a strip by the laminated core manufacturing device illustrated in Fig. 2;

[0021] Fig. 6 is a drawing illustrating the punch tip shape of a piercing punch for processing the outer surface of the first lamina;

[0022] Fig. 7 is an image illustrating a blanking punch and blanking die of the laminated core manufacturing device illustrated in Fig. 2; and

[0023] Figures 8a and 8b are images illustrating a state in which a first lamina and a second lamina are laminated inside a laminated die by the illustrated blanking process.

[0024] Hereinafter, preferred embodiments of the present invention, which can specifically realize the objectives of the present invention, will be described with reference to the attached drawings. In describing these embodiments, the same names and symbols will be used for identical components, and additional descriptions thereof will be omitted below.

[0025] The terms used herein are used to describe embodiments of the present invention and are not intended to limit the present invention. For example, terms related to numbers, such as "first" and "second," are used for convenience in describing embodiments of the present invention and do not define or limit the number of components included in the present invention.

[0026] And when it is said that a component is "connected" to another component, it should be understood that it may be directly connected to that other component, but it also includes an indirect connection, that is, a connection relationship in which another component exists in between.

[0027] In this specification, terms such as “include” or “have” should be understood to not exclude the possibility of adding features or components other than the features or components described in the specification.

[0028] In addition, the laminated core manufacturing device according to the present embodiment can be applied to manufacturing laminated cores using various methods, such as a bonding method (adhesive fixing method) or a tab fixing method using embossing projections.

[0029] Referring to FIGS. 2 to 8, a laminated core manufacturing device according to one embodiment of the present invention includes an upper mold (10), a lower mold (20), a laminated die (100), a blanking punch (200), and a piercing punch (210).

[0030] In this embodiment, the laminated die (100) includes a blanking die (110), and inside the laminated die (100), laminae (L) sequentially formed by blanking processing are stacked.

[0031] And the above blanking punch (200) is provided in an upper mold (10; hereinafter abbreviated as 'upper mold') that can be raised and lowered, and the lower mold (20; hereinafter abbreviated as 'lower mold') is provided on the lower side of the upper mold (10), and the upper mold (10) and the lower mold (20) face each other, and a core manufacturing material (S), i.e., a strip, is intermittently transferred between the upper mold (10) and the lower mold (20).

[0032] The blanking die (110) and the blanking punch (200) face each other, and the stacking die (100) is provided on the lower die (20). Therefore, laminae (L) are sequentially formed by the elevation of the blanking punch (200), and the laminae formed by the present embodiment may include a first lamina (L1) and a second lamina (L2) having different outer diameters.

[0033] Therefore, the laminated core (C) manufactured by the present embodiment may be provided with a layer formed by the first lamina (L1) and the second lamina (L2). That is, the first lamina (L1) and the second lamina (L2) are stacked inside the laminated die (100), so that a laminated core (C) having layers with different outer diameters can be manufactured.

[0034] Hereinafter, for convenience of explanation, the radius (R1) of the first lamina (L1) is referred to as the first radius, the radius (R2) of the second lamina (L2) is referred to as the second radius, and the present embodiment is described based on the case where the radius (R1) of the first lamina (L1) is smaller than the radius (R2) of the second lamina (L2).

[0035] The above-described stacking die (100) has a configuration in which the laminae are stacked, that is, a hollow portion (101), and is axially penetrated. In addition, the stacking die (100) can be rotatably installed on a die support (300) installed on the lower die (200). More specifically, the laminae (L) formed by the blanking punch (200) are sequentially introduced into the hollow portion (101) of the stacking die and stacked, and the stacking core (C) is manufactured by combining the laminae (L1, L2) inside the stacking die (100).

[0036] The above die support (300) is also called a bush, and a bearing (310) may be provided on the die support (300) for rotation of the laminated die, and a pulley (320) for belt transmission may be provided on the outer circumference of the laminated die (100). Since the configuration for rotating the laminated die is known in the art, additional description thereof is omitted.

[0037] FIG. 2 shows an example of a laminated core manufacturing device having the laminated die (100), more specifically, an example of a press device for manufacturing a laminated core using a tab fixing method using embossing projections, particularly a progressive mold.

[0038] Referring to FIG. 2, the upper mold (10) is provided to be able to be lifted above the lower mold (20), and in order to process the metal strip (S) intermittently conveyed from the upper side of the lower mold (20), other punch(s) such as a slot punch (410), a shaft hole punch (420), or an embossing punch (430) may be added to the upper mold (10) in addition to the blanking punch (200) and the piercing punch (210).

[0039] In addition, the lower die (20) is provided with dies (211, 411, 421, 431) corresponding to the piercing punch (210), the slot punch (410), the shaft hole punch (420), and the embossing punch (430). The arrangement of punches for processing the shape of the lamina, such as the piercing punch (210), the slot punch (410), the shaft hole punch (420), and the embossing punch (430), is not limited to the example of FIG. 2 and may be variously changed.

[0040] The above embossing punch (430) is a component that forms an embossing projection by pressing the metal strip to combine the laminas (L) using a tab fixing method, and it is obvious that the embossing punch can be replaced with an adhesive applicator when integrating the laminas using a bonding method.

[0041] It is known in the art that the upper mold may include a punch plate, a punch back plate and an upper holder, and the lower mold may include a die plate, a die back plate and a lower holder.

[0042] The above piercing punch (210) is provided on the mold (10) to form an outer surface of a lamina having the first radius (R1) described above, i.e., a first lamina (L1). In addition, the piercing punch (210) includes punch tips (210a) having an inner end (211a) in an arc shape at a distance of the first radius (R1) and formed in a divided manner along the circumferential direction.

[0043] The above piercing punch (210) is configured to form the first lamina (L1), more specifically, to form the outer surface of the first lamina (L1), and punches the intermittently conveyed strip (S) at a selective time, i.e., at a time when formation of the first lamina is required. Since the technology for controlling the operating time of the punch, i.e., the punching time, in a laminated core manufacturing device is known, additional description thereof is omitted.

[0044] The above punch tip (210a) may have an arc-shaped outer end (211b) formed at a distance of a radius equal to or greater than the second radius (R2).

[0045] And the blanking punch (200) can form the second lamina (L2) and the first lamina (L1) having the second radius (R2) by punching the strip (S). The lower part of the blanking punch (200) has an outer circumferential surface having a radius equal to the second radius (R2), and the blanking punch (200) is provided at a certain distance from the piercing punch (210).

[0046] In the present embodiment, the blanking punch (200) includes punch grooves (201) formed in a circumferential direction on the lower outer surface of the blanking punch (200); the distance from the center of the blanking punch (200) to the punch grooves (201) may be equal to the first radius (R1), or may be smaller or larger than the first radius (R1). In Fig. 4 (a), a case in which the distance from the center of the blanking punch (200) to the punch groove (201) is smaller than the first radius (R1) is exemplified. In Fig. 4 (b), a case in which the distance from the center of the blanking punch (200) to the punch groove (201) is larger than the first radius (R1) is exemplified.

[0047] And the blanking die (110) includes die protrusions (111) that protrude from the inner surface of the blanking die (110) and are formed in a divided manner along the circumferential direction. The die protrusions (111) are configured to face the punch grooves (201), and the punch grooves (201) can be engaged with the die protrusions (111) by lowering the blanking punch (200) to form a combined shape. That is, the punch grooves (201) and the die protrusions (111) can be manufactured to have the same size and shape, and can form grooves (outer grooves; H) on the outer surface of the second lamina as described below. If the distance from the center of the blanking punch (200) to the punch grooves (201) changes, the depth of the outer grooves (H) can change.

[0048] In the present embodiment, the die protrusions (111) are formed vertically on the inner surface of the laminated die (100). When the blanking punch (200) strikes the area processed by the piercing punch (210), the first lamina (L1) is formed as in the example shown in Fig. 8a and is inserted into the interior of the laminated die (100), and the die protrusions (111) support the outer surface of the first lamina (L1). The punch grooves (201) and the die protrusions (111) strike the area between the slots formed by the piercing punch (210).

[0049] And when the blanking punch (200) strikes the area (ST1 non-punching area) that has not been processed by the piercing punch (210), the second lamina (L2) is formed as in the example shown in Fig. 8b and is inserted into the interior of the laminated die (100), and the outer circumference of the second lamina (L2) is supported by the inner circumference of the laminated die (100), and an outer circumference groove into which the die protrusions (111) are fitted is formed on the outer circumference of the second lamina (L2). Fig. 7 is a drawing showing a part of the blanking punch and the laminated die by cutting the blanking punch and the laminated die.

[0050] According to the above-described embodiment, in the area of ​​the piercing punch (210) (first stage; ST1), processing is performed by the piercing punch (210), in the area of ​​the slot punch (410) (second stage; ST2), slot processing is performed, in the area of ​​the shaft hole punch (420) (third stage; ST3), shaft hole processing is performed, in the area of ​​the embossing punch (430) or the adhesive applicator (ST4), embossing processing or adhesive application is performed, and in the area of ​​the blanking punch (200) (fifth stage; ST5), blanking processing is performed.

[0051] Accordingly, by using the above-described laminated core manufacturing device, a method for manufacturing a laminated core can be performed, including a blanking process in which the strip (S) is punched with the blanking punch (200) to first form one of the first lamina (L1) and the second lamina (L2) and then the other lamina is formed later, so that the first lamina (L1) and the second lamina (L2) are laminated inside the laminated die (100).

[0052] At this time, in the region preceding the blanking process, i.e., the entry side of the blanking punch (200), the piercing process by the piercing punch (210) is carried out at an optional time. When the strip (S) is processed by the piercing punch once while the mold is raised and lowered three times, two sheets of second lamina (L2) are continuously laminated between the first laminas (L1), and by controlling the operating timing of the piercing punch, the laminated structure of the first lamina and the second lamina can be variously changed.

[0053] As described above, preferred embodiments of the present invention have been described, and it is obvious to those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit or scope thereof, in addition to the embodiments described above.

[0054] Therefore, the above-described embodiments should be considered as illustrative rather than restrictive, and accordingly, the present invention is not limited to the above description but may be modified within the scope of the appended claims and their equivalents.

[0055] The present invention can be used in the manufacturing of laminated cores, etc., and can be applied to manufacturing laminated cores by forming laminae having different outer diameters and overlapping them.

Claims

1. Elevable upper mold; A piercing punch, which is provided on the upper mold to form an outer surface of a first lamina having a first radius, and includes punch tips having an inner end in an arc shape at a distance of the first radius and formed in a divided manner along the circumferential direction, and which is capable of selectively punching out a strip that is intermittently conveyed to form the first lamina; A blanking punch provided in the upper mold and capable of forming the first lamina and the second lamina having a second radius larger than the first radius of the outer surface by punching the strip, and having a lower end of the second radius and spaced apart from the piercing punch by a certain distance; A lower mold facing the upper mold and provided on the lower side of the upper mold; and A laminated core manufacturing device having a blanking die provided on the lower mold and facing the blanking punch, and including a laminated die on which the first lamina and the second lamina are stacked.

2. In paragraph 1, The above blanking punch includes punch grooves formed along the circumferential direction on the outer surface of the lower portion of the blanking punch; The above blanking die is a laminated core manufacturing device that includes die protrusions formed along the circumferential direction on the inner surface of the blanking die and facing the punch grooves.

3. In the method for manufacturing a laminated core using the laminated core manufacturing device described in paragraph 1 or 2, A method for manufacturing a laminated core, comprising a blanking process of forming one of the first lamina and the second lamina first and forming the other lamina later by punching the strip with the blanking punch so that the first lamina and the second lamina are laminated inside the laminated die.

4. In paragraph 3, A method for manufacturing a laminated core, wherein a piercing process by the piercing punch is selectively performed at an entrance side of the blanking punch.

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