JP2010130824A - Laminated iron core and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated iron core in which core pieces are coupled by caulking with a large joint strength and a high positional accuracy to remarkably improve shape precision, and to provide a method of manufacturing the laminated iron core. <P>SOLUTION: In the laminated iron core, a caulking projection 3A constituting one side of a caulking part 10, and a caulking recess 3B constituting the other side thereof are provided, and the iron cores are caulked and coupled by engaging a projection 3j and a tongue 3t of the caulking projection in one iron piece 3 with a caulking projection engaging hole 3o and a notch 3n of the other recess. A manufacturing method includes: forming the caulking projection and the caulking recess in a metal plate by punching, and caulking and coupling the iron pieces by punching the core piece from the metal plate into a predetermined shape, and engaging the projection and tongue of the caulking projection in the core piece with the caulking projection engaging hole and notch of the caulking recess in the pre-punched core piece. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

    The present invention relates to a laminated iron core formed by caulking and bonding a plurality of laminated iron core pieces to each other via a caulking portion formed on the iron core piece. Further, the caulking portion is formed by punching a metal plate by a press device. The present invention relates to a method of manufacturing a laminated core in which an outer shape of an iron core piece having a predetermined shape is removed and a plurality of iron core pieces are caulked and joined together via caulking portions.

    For example, a laminated iron core such as a drive motor is usually manufactured by punching and forming iron core pieces from a metal plate using a pressing device, laminating a predetermined number of iron core pieces, and caulking them together.

  Conventionally, for crimping of laminated cores, half-cut protrusions or V-shaped protrusions are formed on the core piece, and the half-cut protrusion back-side recesses or V-shaped protrusion back-side recesses formed on the core pieces that have been previously cut out In addition, the above-described half-cut projection or V-shaped projection is inserted.

  Here, in laminated iron cores such as drive motors, there is no gap between the laminated iron core pieces, and there is a gap or separation between the iron core pieces during the manufacturing process or during assembly or handling of the motor. It is important that the iron core pieces are firmly caulked and integrated with each other.

  As described above, according to the configuration in which the half-cut protrusion formed on the core piece is fitted into the recess on the back side of the half-cut protrusion of the other core piece, and the core pieces are caulked and joined together, the core pieces are integrated with high positional accuracy. While a laminated iron core with excellent shape accuracy can be obtained, it is difficult to say that the strength of caulking is necessarily strong, and if an inadvertent impact is applied during handling of the laminated core, There was a risk that a gap might be formed between them, or the laminated iron core might be separated if it was severe.

  On the other hand, as described above, according to the configuration in which the V-shaped protrusion formed on the iron core piece is inserted into the V-shaped protrusion rear side recess of the other iron core piece, and the iron core pieces are caulked and joined together, Since both sides of the slab engage with both side edges of the V-shaped protrusion back side recess, the strength of the caulking connection is extremely high, but the inclined parts of the V-shaped protrusion interfere with each other (compete). In addition, there is a problem in that the shape accuracy of the laminated iron core such as the degree of perpendicularity is lowered due to a decrease in the position accuracy between the core pieces.

  Therefore, as an example of a technique for solving the above-described disadvantages, a configuration is provided in which the inclined portions are prevented from interfering with each other by reducing the plate thickness of the inclined portions in the V-shaped projections (for example, patents). Reference 1).

FIG. 9 is an example of a laminated iron core adopting the above-described configuration, and the caulking portion C in the laminated iron core A includes a V-shaped protrusion Bj and a V-shaped protrusion rear-side recess Bo formed on the iron core piece B. The inclined portions Bjs, Bjs in the V-shaped protrusion Bj are formed thin, and the V-shaped protrusion Bj is fitted into the V-shaped protrusion back side concave portion Bo of the lower core piece 3, The laminated core A is manufactured by caulking and joining the core pieces B together.
Japanese Patent Laid-Open No. 10-80078

    By the way, according to the laminated core A having the above-described configuration, the V-shaped protrusions Bj formed on the core piece B are fitted into the V-shaped protrusion back-side recess Bo of the other core piece B, so The strength of the caulking portion is extremely high, and the thickness of the inclined portions Bjs and Bjs in the V-shaped protrusion Bj of the caulking portion C is reduced, so that interference (competition) between the inclined portions Bjs is prevented. It is possible to suppress a decrease in shape accuracy in the iron core.

  However, in the configuration as described above, since the V-shaped protrusion Bj has a shape having the inclined portions Bjs and Bjs, it is difficult to completely prevent the misalignment between the laminated core pieces B. When B, B... Are inclined and laminated, there is an inconvenience that the lowering of the perpendicularity in the laminated core A, in other words, the reduction of the shape accuracy cannot be completely eliminated.

  An object of the present invention is to achieve a significant improvement in shape accuracy by being caulked and bonded with high bonding strength between core pieces and with high positional accuracy in view of the above-described actual situation. It is an object of the present invention to provide a laminated iron core that can be manufactured and a method for producing the laminated iron core.

In order to achieve the above object, the laminated core according to the invention of claim 1 is a laminated iron core formed by caulking and bonding a plurality of laminated iron core pieces to each other via caulking portions formed on the iron core pieces.
The caulking projection constituting one of the caulking portions has a protruding portion protruding in the thickness direction of the iron core piece, and a tongue piece protruding in the width direction from the side edge of the protruding portion,
The caulking recess that constitutes the other of the caulking portions is formed in an iron core piece and engages with the caulking protrusion engaging portion, and the caulking protrusion tongue is formed on the edge of the caulking protrusion engaging hole. A notch with which one part engages,
In a state where a plurality of iron core pieces are stacked, by engaging the protrusions and tongue pieces of the caulking protrusions in one iron core piece with the caulking protrusion engaging holes and notches of the caulking recesses in the other iron core piece, It is characterized by caulking the pieces together.

  The laminated iron core according to the invention of claim 2 is characterized in that, in the laminated iron core according to the invention of claim 1, the tongue piece portion of the caulking projection in the iron core piece is formed only on one side edge of the projection portion.

According to a third aspect of the present invention, there is provided a method of manufacturing a laminated iron core, comprising: pressing a stamped portion on a metal plate by a press device; extracting a core piece of a predetermined shape from the metal plate; and removing a plurality of core pieces through the crimped portion. A method of manufacturing a laminated iron core that is caulked to each other,
A caulking projection constituting one of the caulking portions is punched and formed on a metal plate by providing a protruding portion protruding in the thickness direction of the iron core piece and a tongue piece protruding in the width direction from the side edge of the protruding portion. And a step of punching and forming a caulking recess that constitutes the other of the caulking portion by providing a caulking projection engaging hole that opens to the iron core piece and a notch that faces an edge of the caulking projection engaging hole;
The outer shape of the iron core piece is extracted from the metal plate into a predetermined shape, and the protrusion and tongue piece of the caulking protrusion on the iron core piece are engaged with the caulking protrusion engaging hole and the notch of the caulking recess in the iron core piece that has been previously outer shaped. And a step of caulking and bonding the iron core pieces to each other.

    According to the laminated iron core relating to the invention of claim 1, in a state where a plurality of iron core pieces are laminated, the caulking protrusion of one iron core piece is fitted into the caulking concave portion of the other iron core piece, whereby the protrusion of the caulking protrusion is formed. And the tongue portion of the caulking protrusion engages with the notch of the caulking concave portion, so that the caulking by the conventional half-drawing protrusion or V-shaped protrusion described above is engaged. Compared with the bonding, the core pieces can be caulked and bonded with a much stronger bonding strength.

  Further, according to the laminated iron core according to the present invention, in a state where a plurality of iron core pieces are laminated, the protruding portion of the caulking protrusion engages with the caulking protrusion engaging hole of the caulking recess, and the protruding portion of the caulking protrusion The tongue piece protruding in the width direction from the side edge engages with the notch formed in the edge of the caulking protrusion engaging hole in the caulking recess, so that the caulking part is restrained in two directions intersecting each other. As a result, the positional accuracy of the core pieces that are laminated and crimped together is improved, so that the shape accuracy of the laminated core such as the verticality can be greatly improved.

  Furthermore, according to the laminated iron core related to the present invention, since the engagement between the caulking protrusion and the caulking concave portion is extremely strong as described above, the number of places where the caulking portion is formed with respect to the laminated iron core can be reduced, and thus the manufacture. The simplification of the process can be achieved, and the deterioration of the iron loss characteristic due to the presence of the caulking portion can be suppressed as much as possible.

  According to the laminated iron core related to the invention of claim 2, in combination with the above-described effects, the tongue piece portion of the caulking protrusion in the iron core piece is formed only on one side edge of the protrusion portion, and the shape of the caulking portion is formed. As a result of simplification, it is possible to simplify the workability related to the formation of the crimped portion and the manufacture of the laminated core, in addition to the operational effects related to the configuration of claim 1 described above.

  According to the method for manufacturing a laminated core according to the invention of claim 3, when the outer shape of the core piece is extracted from the metal plate into a predetermined shape, the caulking protrusion on one iron core piece is inserted into the caulking recess on the other iron core piece. Thus, the above-mentioned conventional half-projection projection is obtained by engaging the projection portion of the crimping projection with the crimping projection engaging hole of the crimping recess and the tongue piece portion of the crimping projection with the notch of the crimping recess. Compared with the caulking coupling using the V-shaped projections or the V-shaped projections, the iron core pieces can be caulked to each other with a much stronger coupling strength.

  Further, according to the method of manufacturing a laminated core according to the present invention, when the outer shape of the core piece is extracted from the metal plate into a predetermined shape, the protruding portion of the crimping protrusion is engaged with the crimping protrusion engaging hole of the crimping recess, By engaging the tongue piece protruding in the width direction from the side edge of the protrusion in the caulking protrusion with the notch formed in the edge of the caulking protrusion engaging hole in the caulking recess, the caulking parts intersect each other. It is constrained in two directions, so that the positional accuracy of the core pieces that are laminated and crimped together is improved, so that the shape accuracy of the laminated core such as the verticality can be greatly improved.

  Furthermore, according to the method for manufacturing a laminated core according to the present invention, since the engagement between the caulking projection and the caulking recess is extremely strong as described above, the number of locations where the caulking portion is formed with respect to the laminated iron core can be reduced. Thus, simplification of the manufacturing process can be achieved, and a reduction in iron loss characteristics due to the presence of the caulking portion can be suppressed as much as possible.

Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments.
FIG. 1 shows an embodiment in which the present invention is applied to a laminated core constituting a stator of a drive motor. This laminated iron core 1 connects a predetermined number of divided iron cores (laminated iron cores) 2, 2,. And a yoke portion having an annular shape, and a predetermined number of teeth portions projecting radially inward from the yoke portion.

  As shown in FIG. 2, each of the divided laminated cores 2 has a divided yoke part 2Y that constitutes a part of the yoke part in the laminated core 1, and one tooth part 2T that protrudes from the divided yoke part 2Y. .. Are laminated together by caulking portions 10 and 10 formed in the divided yoke portion 2Y and the tooth portion 2T.

  As shown in FIGS. 2 and 3, the caulking portion 10 is formed by engaging the caulking protrusion 3 </ b> A formed on one iron core piece 3 with the caulking recess formed on the other iron core piece 3. 4 and FIG. 5, each core piece 3 includes a caulking projection 3 </ b> A constituting one of the caulking portions 10 and the other of the caulking portions 10. The caulking recess 3B is formed.

  The caulking portion 10 is formed by punching from a metal plate by a press device (not shown), as will be described in detail later, and the caulking protrusion 3A constituting one of the caulking portions 10 is a plate of the iron core piece 3. It has a protruding portion 3j protruding in the thickness direction and tongue pieces 3t, 3t protruding in the width direction from the side edges 3je, 3je of the protruding portion 3j.

  The protrusion 3j has a substantially rectangular shape in a plan view, and a tongue piece portion having a rectangular shape in a plan view is provided at a substantially central portion of each of the side edges 3je and 3je sheared from the metal plate (iron core piece 3). 3t and 3t are protrudingly formed.

  On the other hand, the caulking concave portion 3B constituting the other of the caulking portion 10 includes a caulking protrusion engaging hole 3o having a substantially rectangular planar shape corresponding to the protruding portion 3j of the caulking protrusion 3A, and the caulking protrusion engaging hole 3o. There are notches 3n and 3n having a rectangular shape in a plan view corresponding to the tongue pieces 3t and 3t of the caulking projection 3A, which open to face the edge 3oe.

  Incidentally, in the crimping portion 10 formed in the yoke portion of the laminated core 1, the longitudinal direction (the xx direction in FIG. 2) of the crimping projection 3 </ b> A and the crimping recess 3 </ b> B extends along the circumferential direction of the laminated core 1. The caulking portion 10 formed in the position mode and the caulking portion 10 formed in the tooth portion of the laminated core 1 has the longitudinal direction of the caulking projection 3A and the caulking concave portion 3B (the xx direction in FIG. 2) in the laminated iron core. It is formed in a position mode extending along the radial direction of 1.

  As shown in FIGS. 2 and 3, the split iron core (laminated iron core) 2 of the laminated core 1 shown in the embodiment has a caulking protrusion 3A of the caulking portion 10 and a caulking protrusion 10A by a press device (not shown), as will be described in detail later. After punching and forming the caulking recess 3B, the protrusions 3j and tongues 3t and 3t of the caulking protrusion 3A in one iron core piece 3 are used as the caulking protrusion engaging holes 3o and the notches in the caulking recess 3B in the other iron core piece 3. By being engaged with 3n and 3n, the laminated iron core pieces 3 are connected by caulking to each other.

  That is, according to the laminated core 1 having the above-described configuration, the caulking protrusion 3A of one iron core piece 3 is fitted into the caulking recess 3B of the other iron core piece 3 in a state where the plurality of iron core pieces 3, 3. As a result, the protrusion 3j of the caulking protrusion 3A engages with the caulking protrusion engaging hole 3o of the caulking recess 3B, and the tongue pieces 3t and 3t of the caulking protrusion 3A are notched 3n in the caulking recess 3B. By engaging with 3n, iron core pieces 3 can be caulked and joined with a remarkably stronger coupling strength as compared with the caulking coupling with conventional half-bumped projections or V-shaped projections.

  Further, according to the laminated core 1 having the above-described configuration, the protruding portion 3j of the crimping projection 3A engages with the crimping projection engaging hole 3o of the crimping recess 3B in a state where the plurality of core pieces 3, 3,. In addition, tongue pieces 3t and 3t projecting in the width direction from the side edges 3je and 3je of the projection 3j in the crimping projection 3A are formed facing the edges 3oe and 3oe of the crimping projection engagement hole 3o in the crimping recess 3B. By engaging with the notches 3n and 3n, the caulking portion 10 is restrained in two directions intersecting each other, that is, in the xx direction in FIG. 2 and the yy direction in FIG. Thus, by improving the positional accuracy between the core pieces 3 that are laminated and crimped together, the shape accuracy of the laminated core 1 such as the verticality can be greatly improved.

  Furthermore, according to the laminated iron core 1 having the above-described configuration, since the engagement between the caulking protrusion 3A and the caulking concave portion 3B is extremely strong, the number of places where the caulking portion 10 is formed on the laminated iron core 1 can be reduced. Thus, simplification of the manufacturing process can be achieved, and a reduction in iron loss characteristics due to the presence of the caulking portion 10 can be suppressed as much as possible.

Below, the method to manufacture the laminated core 1 of the structure mentioned above is demonstrated.
FIG. 6 is a plan view of a metal plate (strip steel plate) W processed by a press device (sequential feed die device) (not shown) based on the method for manufacturing a laminated core according to the present invention. Through the processing stations S1 to S7 (not shown), the laminated iron core 1 is manufactured by caulking the iron core pieces 3, 3,..., And the iron core pieces 3, 3,.

  First, pilot holes Wp, Wp... Are formed in the processing station S1, slots Ws, Ws... Are formed in the processing station S2, and separations Wl, Wl... For dividing the yoke are formed in the processing station S3. Punching forming.

  Next, in the processing station S5, the caulking projection 3A and the caulking recess 3B constituting the caulking portion 10 are formed by punching.

  That is, in the processing station S5, the caulking protrusion 3A constituting one of the caulking parts 10 is protruded in the width direction from the protruding part 3j protruding in the thickness direction of the iron core piece 3 and the side edges 3je and 3je of the protruding part 3j. The tongue piece portions 3t and 3t are formed by punching, and the caulking concave portion 3B constituting the other of the caulking portion 10 is formed with a caulking projection engaging hole 3o that opens into the iron core piece 3, and the caulking projection engaging hole 3o. The notches 3n and 3n facing the edges 3oe and 3oe are provided and punched.

  As described above, after the caulking projection 3A and the caulking recess 3B constituting the caulking portion 10 are punched and formed at the processing station S5, the outer shape of the divided yoke portion is punched out at the processing station S7 after the play processing station S6. Are formed separately.

  In the processing station S7, the individual iron core pieces 3, 3... Are separated and formed as described above, and the protrusions 3j and the tongue pieces 3t, 3t of the caulking protrusion 3A of the iron core piece 3 are first removed from the outer shape. The laminated core 1 is manufactured by engaging the crimping protrusion engaging holes 3o and the notches 3n and 3n of the crimping recesses 3B of the core pieces 3, 3.

  That is, according to the method for manufacturing a laminated core as described above, when the core piece 3 is extracted from the metal plate W in a predetermined shape, the caulking protrusion 3A on one iron core piece 3 is replaced with the caulking recess 3B on the other iron core piece 3. By fitting into the caulking projection 3A, the projection 3j of the caulking projection 3A is engaged with the caulking projection engaging hole 3o of the caulking recess 3B, and the tongue pieces 3t, 3t of the caulking projection 3A are notched 3n of the caulking recess 3B. By engaging with 3n, it becomes possible to crimp the core pieces 3 to each other with a much stronger coupling strength than conventional crimping coupling with half-drawn projections or V-shaped projections.

  Further, according to the method for manufacturing a laminated core as described above, when the core piece 3 is extracted from the metal plate W into a predetermined shape, the protrusion 3j of the caulking protrusion 3A is connected to the caulking protrusion engaging hole 3o of the caulking recess 3B. The tongue pieces 3t and 3t protruding in the width direction from the side edges 3je and 3je of the projection 3j in the caulking projection 3A are engaged with the edges 3oe and 3oe of the caulking projection engaging hole 3o in the caulking recess 3B. By engaging with the formed notches 3n and 3n, the caulking portion 10 is restrained in two directions intersecting each other, that is, in the xx direction in FIG. 2 and the yy direction in FIG. As a result, the positional accuracy of the core pieces 3 laminated and crimped together is improved, so that the shape accuracy of the laminated core 1 such as the verticality can be greatly improved.

  Furthermore, according to the method for manufacturing a laminated core as described above, the engagement between the caulking protrusion 3A and the caulking recess 3B is extremely strong as described above, so that the number of places where the caulking portion 10 is formed with respect to the laminated core 1 is reduced. Thus, the manufacturing process can be simplified, and the deterioration of the iron loss characteristic due to the presence of the crimping portion 10 can be suppressed as much as possible.

  FIG. 7 shows another embodiment of the laminated iron core according to the present invention. The tongue piece portions 3t and 3t of the caulking projection 3A constituting one of the caulking portions 10 in this embodiment have an R at the corner portion. The portions 3tr and 3tr are formed, and the R portions 3nr and 3nr are also formed at the corner portions of the notches 3n and 3n in the caulking concave portion 3B corresponding to the tongue pieces 3t and 3t of the caulking projection 3A.

  1 except that the R portions 3tr and 3tr are formed at the corner portions of the tongue pieces 3t and 3t, and the R portions 3nr and 3nr are formed at the corner portions of the notches 3n and 3n. There is no difference from the configuration of the laminated core 1 shown in FIG.

  According to the laminated core 1 having the above-described configuration, it is possible to obtain the same effect as the laminated core 1 shown in FIGS. Thus, the manufacturing cost can be reduced.

  FIG. 8 shows still another embodiment of the laminated iron core according to the present invention. The caulking projection 3A ′ constituting one of the caulking portions 10 ′ in this embodiment has one side edge 3je of the protruding portion 3j ′. The tongue piece 3t 'is projected only on the ′, and the caulking projection engaging hole 3o ′ of the caulking recess 3B ′ constituting the other of the caulking portion 10 ′ corresponds to the tongue piece 3t ′. Only one notch 3n 'is formed.

  The configuration of the laminated core 1 ′ is the same as the configuration of the laminated core 1 shown in FIGS. 1 to 3 except that the tongue pieces 3t ′ and the notches 3n ′ are formed one by one. Elements having the same functions as those of the components of the laminated core 1 are denoted by the same reference numerals as those in FIGS. 1 to 3 in FIG.

  According to the laminated core 1 ′ having the above-described configuration, the same effect as that of the laminated core 1 shown in FIGS. 1 to 3 can be obtained, and the planar shape of the crimped portion 10 ′ is simplified. 10 'can be easily formed by punching, and the manufacturing cost can be reduced.

  In addition, similarly to the laminated core shown in FIG. 7, it is possible to form an R portion at the corners of the tongue piece 3t ′ and the notch 3n ′. With such a configuration, the laminated core can be manufactured. The cost involved can be further reduced.

  Here, in the above-described embodiment, the example in which the present invention is applied to the laminated iron core constituting the stator of the drive motor is shown, but the present invention is applied to various laminated iron cores other than the stator of the drive motor. It goes without saying that can be applied effectively.

  Further, in the above-described embodiment, the laminated core manufactured by connecting a predetermined number of divided cores is targeted, and the caulking connection of the core pieces laminated in the divided core is described in detail. However, the present invention is divided. A laminated core formed by laminating core pieces of a predetermined shape and caulking and joining each of the core pieces, and further, a strip-shaped core piece formed by connecting a plurality of divided core pieces (segment core pieces) in a strip shape. In addition, the present invention can be applied to a laminated iron core manufactured by laminating while being spirally wound and bonded together, and in any application mode, the laminated iron core and the manufacturing method shown in the examples Of course, the same effects can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS The whole perspective view which shows one Example of the laminated iron core in connection with this invention. (a) And (b) is an external appearance perspective view of the split iron core which comprises the laminated iron core shown in FIG. 1, and the principal part top view of a split iron core. (a) And (b) is the sectional view on the aa line in FIG.2 (b), and the sectional view on the bb line in FIG.2 (b). The principal part perspective view of the iron core piece which comprises the split iron core of the laminated iron core shown in FIG. (a), (b) and (c) are the principal part top views of the core piece which comprises the split iron core of the laminated core shown in FIG. 1, the bb sectional view taken on the line in (a), and (a) The cc sectional view taken on the line. The top view of the metal plate which shows the process in the manufacturing method of the laminated iron core in connection with this invention. (a), (b), and (c) are the principal part top view of the core piece which shows the other Example of the laminated iron core concerning this invention, the principal part top view of a caulking recessed part, and the principal part top view of a caulking protrusion . (a), (b), and (c) are the principal part top views of the core piece which shows the further another Example of the laminated core concerning this invention, bb sectional view taken on the line in (a), ) In FIG. (a) And (b) is a principal part top view which shows the crimping | crimped part in the conventional laminated iron core, and the bb sectional view taken on the line in (a).

Explanation of symbols

1 ... laminated iron core,
2 ... split core (laminated core),
2Y: Divided yoke part,
2T ... Teeth,
3 ... Iron core piece,
3A ... caulking protrusion,
3j ... protrusions,
3t ... tongue part,
3B ... caulking recess,
3o: Caulking protrusion engaging hole,
3n ... Notches,
10 ... Caulking part.

Claims (3)

A laminated iron core formed by caulking and bonding a plurality of laminated iron core pieces via caulking portions formed on the iron core piece,
The caulking projection constituting one of the caulking portions has a protruding portion protruding in the plate thickness direction of the iron core piece, and a tongue piece portion protruding in the width direction from the side edge of the protruding portion,
The caulking recess that constitutes the other of the caulking portions is formed on the iron core piece and is formed at the edge of the caulking protrusion engaging hole, and the caulking protrusion engaging hole that engages with the protruding portion of the caulking protrusion. A notch with which the tongue piece of the caulking protrusion engages,
In a state where a plurality of the iron core pieces are stacked, the protrusions and the tongue pieces of the caulking protrusions in one iron core piece, the caulking protrusion engaging holes and the cuts of the caulking recesses in the other iron core piece, A laminated core characterized in that the core pieces are crimped together by engaging with the notches. The laminated core according to claim 1, wherein the tongue piece portion of the caulking protrusion in the iron core piece is formed only on one side edge of the protrusion. A method of manufacturing a laminated core in which a crimping portion is punched and formed on a metal plate by a pressing device, a core piece having a predetermined shape is extracted from the metal plate, and a plurality of the core pieces are crimped together via the crimping portion. And
On the metal plate, a caulking protrusion constituting one of the caulking portions is provided with a protruding portion protruding in the plate thickness direction of the iron core piece and a tongue piece portion protruding in the width direction from a side edge of the protruding portion. In addition to punching and forming, a caulking recess that constitutes the other of the caulking portion is formed by providing a caulking protrusion engaging hole that opens to the iron core piece and a notch that faces an edge of the caulking protrusion engaging hole. Process,
The iron core piece is extracted from the metal plate in a predetermined shape, and the protrusion and the tongue piece of the caulking protrusion in the iron core piece are connected to the caulking protrusion of the caulking recess in the iron core piece having the outer shape previously extracted. Engaging the hole and the notch, and caulking the core pieces together;
A method for producing a laminated iron core, comprising:

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