Progressive die device and method for manufacturing thin iron core plates

Abstract

To increase the degree of freedom in arranging a pilot pin. [Solution] Multiple pilot holes P are punched and formed for each transfer of the strip-shaped thin plate F during intermittent transfer, and in one of the processing stages, a pilot pin 80 is positioned so as to use one of the multiple pilot holes P, and in another of the processing stages, a pilot pin 80 is positioned so as to use one of the multiple pilot holes P other than the one.

Description

Technical Field

[0001] The present invention relates to a progressive die device for manufacturing iron core thin plates and a method for manufacturing iron core thin plates.

Background Art

[0002] Conventionally, a progressive die is known as a manufacturing device for laminated iron cores (iron core thin plates) used in motor cores and the like. In a progressive die, a plurality of processing stages are provided in which necessary processing is sequentially performed on a strip-shaped thin plate (hoop material). In each processing stage, punching of pilot holes (positioning holes), punching of internal shapes (internal shapes such as slots and teeth), formation of caulking parts, application of adhesives, etc. are performed as required. As a result, in the strip-shaped thin plate conveyed in the progressive die, the shapes of the respective thin plate pieces constituting the laminated iron core are continuously formed. Finally, the iron core thin plates whose outer shapes have been punched out from the strip-shaped thin steel plate are fixed in a state where a predetermined number of them are laminated in the progressive die, thereby completing the laminated iron core.

[0003] In the manufacture of iron core thin plates using a progressive die, the strip-shaped thin plate is intermittently conveyed at a predetermined pitch (hereinafter referred to as a transfer pitch), and the pilot pins are engaged with the pilot holes formed in the strip-shaped thin plate, thereby positioning the strip-shaped thin plate with respect to the progressive die. In the positioned state, predetermined processing such as internal shape punching and outer shape punching is performed in each processing stage (for example, Patent Documents 1 and 2). The progressive die may be provided with movable parts such as a plate cam and a rotary die that change the effective length of the punch for caulking formation for measurement.

[0004] As the first step in the manufacture of iron core thin plates using a progressive die, for each transfer of the strip-shaped thin plate in intermittent transfer, one pilot hole is drilled in each of both side edges of the strip-shaped thin plate. In this drilling, the pilot holes are aligned in the transfer direction at the same interval as the transfer pitch along each side edge of the strip-shaped thin plate.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Publication No. 2015-5649 [Patent Document 2] Japanese Patent Publication No. 2021-93908 [Overview of the project] [Problems that the invention aims to solve]

[0006] The pilot holes are spaced at the same intervals as the transport pitch of the strip-shaped thin plate, resulting in limited flexibility in their placement. Similarly, the placement of the pilot pins that engage with the pilot holes also has limited flexibility. Therefore, even if the placement of the pilot pins is changed as much as possible, interference between the pilot pins and movable parts such as plate cams and rotating dies may not be avoided. Avoiding such interference would require complication of the structure of the movable parts, leading to a decrease in component strength and a decline in workability and maintainability.

[0007] In view of the above background, the present invention aims to increase the degree of freedom in the placement of the pilot pin. [Means for solving the problem]

[0008] To solve the above problems, one aspect of the present invention provides a progressive die apparatus for manufacturing an iron core sheet of a predetermined shape by performing a predetermined process on a strip-shaped sheet that is intermittently transported at a predetermined pitch, at each of a plurality of processing stages set to be aligned in the transport direction of the strip-shaped sheet, the apparatus comprising: a pilot hole forming unit that punches out a plurality of pilot holes for each transport of the strip-shaped sheet in intermittent transport; and at least one pilot pin provided corresponding to each of the processing stages, which engages with the corresponding pilot hole to position the strip-shaped sheet at each processing stage, wherein in one of the processing stages, the pilot pin is positioned to engage with one of the plurality of pilot holes, and in another of the processing stages, the pilot pin is positioned to engage with a pilot hole other than the one mentioned above.

[0009] According to this embodiment, the degree of freedom in the positioning of the pilot hole into which the pilot pin engages is increased, and consequently, the degree of freedom in the positioning of the pilot pin is also increased.

[0010] In the above embodiment, the pilot hole forming section may be configured such that the plurality of pilot holes are aligned in the transport direction.

[0011] According to this embodiment, the degree of freedom in the placement of the pilot pins is increased with respect to the transport direction of the strip-shaped thin plate.

[0012] In the above embodiment, the pilot hole forming section may be configured such that the plurality of pilot holes are aligned in the transport direction along each of the side edges of the strip-shaped thin plate.

[0013] According to this embodiment, the degree of freedom in the placement of the pilot pins is increased with respect to the transport direction of the strip-shaped thin plate at positions corresponding to each side edge of the strip-shaped thin plate.

[0014] In the above embodiment, each of the processing stages is equipped with a processing member that performs a predetermined process on the strip-shaped thin plate, and the pilot pin engages with one of the pilot holes, which does not interfere with the processing member, among the plurality of pilot holes formed at multiple locations separated from the processing member in the transport direction on each of the processing stages.

[0015] According to this embodiment, the degree of freedom in the placement of the pilot pins is increased with respect to the transport direction of the strip-shaped thin plate.

[0016] In the above embodiment, one of the processing stages is a crimping stage equipped with a crimping punch and a crimping die for forming a crimped portion on the strip-shaped thin plate, and a cam for increasing or decreasing the effective length of the crimping punch, wherein the processing member that is subject to interference with the pilot pin is the cam.

[0017] In this embodiment, interference between the pilot pin and the cam is avoided.

[0018] In the above aspect, as one of the processing stages, there is an adhesive application stage including an adhesive application device for applying an adhesive to the strip-shaped thin plate, and the processing member that is an interference target with the pilot pin is the adhesive application device.

[0019] According to this aspect, interference between the pilot pin and the adhesive application device is avoided.

[0020] In the above aspect, as one of the processing stages, there is a punching stage including a punch and a rotary die, and the processing member that is an interference target with the pilot pin is the rotary die.

[0021] According to this aspect, interference between the pilot pin and the rotary die is avoided.

[0022] In order to solve the above problems, an aspect of the present invention is a manufacturing method for manufacturing a core thin plate having a predetermined shape by performing predetermined processing in each of a plurality of processing stages aligned in the transfer direction of the strip-shaped thin plate intermittently transferred at a predetermined pitch by a forward feeding die device. In each transfer in the intermittent transfer, a plurality of pilot holes are punched and formed by a pilot hole forming portion, and provided corresponding to each of the processing stages, at least one pilot pin engages with the corresponding pilot hole to position the strip-shaped thin plate in each processing stage. In some of the processing stages, one of the plurality of pilot holes is used, and in another one of the processing stages, one other than the one of the plurality of pilot holes is used.

[0023] According to this aspect, the degree of freedom in the arrangement position of the pilot holes with which the pilot pin engages increases, and accordingly, the degree of freedom in the arrangement position of the pilot pin increases.

[0024] In the above aspect, the plurality of pilot holes may be aligned in the transfer direction.

[0025] According to this aspect, the degree of freedom in the arrangement position of the pilot pin becomes higher with respect to the transfer direction of the strip-like thin plate.

Advantages of the Invention

[0026] According to the above aspect, the degree of freedom in the arrangement position of the pilot pin becomes higher.

Brief Description of the Drawings

[0027] [Figure 1] Plan view showing a specific example of a core thin plate used for a laminated core [Figure 2] Explanatory drawing showing a strip layout in the case of single-row picking by the progressive die device of Embodiment 1 of the present invention [Figure 3] Cross-sectional view of the progressive die device of Embodiment 1 [Figure 4] Cross-sectional view taken along line X-X of FIG. 3 [Figure 5] Explanatory drawing showing a strip layout in the case of two-row picking by the progressive die device of Embodiment 1 [Figure 6] Explanatory drawing showing a strip layout in the case of single-row picking by the progressive die device of Embodiment 2 of the present invention [Figure 7] Cross-sectional view of the progressive die device of Embodiment 2

Modes for Carrying Out the Invention

[0028] Hereinafter, embodiments of the progressive die device and the method for manufacturing a core thin plate according to the present invention will be described with reference to the drawings. For the sake of convenience in explanation, the directions are defined by up and down, front and back, and left and right indicated by arrows in each drawing. However, the progressive die according to the present invention and the manufacturing method using the same are not necessarily limited by those directions.

[0029] (Embodiment 1) Embodiment 1 will be described with reference to FIGS. 1 to 4.

[0030] First, with reference to Figure 1, a specific example of the core sheet A used in laminated cores will be explained. The core sheet A is a press-formed product obtained by punching out a predetermined shape from a strip-shaped sheet (hoop material) F (see Figure 2) using a progressive die device 10, which will be explained next. The core sheets A are laminated, and in Embodiment 1, adjacent sheets are joined together by riveting.

[0031] The iron core sheet A has an annular yoke portion B, a plurality of teeth portions (magnetic pole portions) C extending radially inward from the yoke portion B, and a plurality of crimped portions D formed on the yoke portion B.

[0032] The manufacturing process for the iron core sheet A involves the following steps being performed in order, as shown in Figure 2: a pilot hole punching step (I) to punch out pilot holes P, a slit punching step (II) to punch out slots S between adjacent tooth portions C, a crimping portion forming step (III) to emboss each crimping portion D, an internal shape punching step (IV) to punch out a circular internal shape G to define the tip of the tooth portion C, and an external shape punching step (V) to punch out a circular external shape H of the yoke portion B.

[0033] Next, the progressive die apparatus 10 of Embodiment 1 will be described with reference to Figure 3. The progressive die apparatus 10 comprises an upper die 20 and a lower die 60 arranged to sandwich a strip-shaped thin plate F from above and below.

[0034] The upper die 20 has a plate-shaped upper holder 22 fixed to the lower surface of the upper ram (not shown) of the press machine. This allows the upper die 20 to move vertically to approach and move away from the lower die 60. In the upper die 20, a backing plate 24 and a punch plate 26 are attached to the lower part of the upper holder 22. The punch plate 26 fixes the pilot hole punch 28, slot punch 30, crimping part forming punch 32, inner shape punch 34, and outer shape punch 36 to the upper holder 22, respectively. The backing plate 24 prevents the processing force of each punch 28, 30, 32, 34, and 36 from being directly applied to the upper holder 22. A plate cam 38 for metering control, which increases or decreases the effective length of the crimping part forming punch 32, is mounted on the backing plate 24 at a position corresponding to the crimping part forming punch 32 and is movable in the left-right direction.

[0035] In the upper mold 20, a stripper 40 is attached below the upper holder 22. The stripper 40 is displaceable in the vertical direction relative to the upper holder 22. The lowest position of the stripper 40 relative to the upper holder 22 is set by suspension support by suspension bolts (not shown). The stripper 40 is constructed as a joint between a stripper body 40A and a stripper 40B, each having a plate-like shape.

[0036] The lower surface of the stripper 40 faces the upper surface of the die plate 64 and each die 68, 70, 72, 74, and 76, which will be described later. The stripper 40 has punch through holes 42, 44, 46, 48, and 50 through which each punch 28, 30, 32, 34, and 36 passes.

[0037] The lower die 60 has a plate-shaped lower holder 62 fixed to the upper surface of the lower bolster (not shown) of the press machine. The lower holder 62 is positioned opposite the upper holder 22. In the lower die 60, a plate-shaped die plate 64 is attached to the upper surface of the lower holder 62. A die plate 64 has a pilot hole punching die 68, a slot punching die 70, a crimping part forming die 72, an inner shape punching die 74, and an outer shape punching die 76 attached to it. The outer shape punching die 76 is cylindrical and constitutes a rotating die that rotates in segments around its central axis at a predetermined rotation angle. The crimping part forming punch 32, plate cam 38, and slot punching die 70 constitute the crimping part forming member.

[0038] Each punch 28, 30, 32, 34, 36 and each die 68, 70, 72, 74, 76 correspond to each other, forming individual processing stages spaced apart from one another in the transport direction of the strip-shaped thin plate F. The processing stages consist of: pilot hole punching punch 28 and pilot hole punching die 68 forming pilot hole punching stage (pilot hole forming section) I; slot punching punch 30 and slot punching die 70 forming slot punching stage II; crimping part forming punch 32 and crimping part forming die 72 forming crimping part forming stage III; internal shape punching punch 34 and internal shape punching die 74 forming internal shape punching stage IV; and external shape punching punch 36 and external shape punching die 76 forming external shape punching stage V.

[0039] The slot punching stage II, the crimping stage III, the internal shape punching stage IV, and the external shape punching stage V are processing stages that perform predetermined processes in the progressive die device 10. The punches 28, 30, 32, 34, 36, dies 68, 70, 72, 74, 76, and plate cam 38 provided in each of the stages II to V constitute processing members that perform predetermined processes on the strip-shaped thin sheet F in each of the processing stages described above. Thus, each processing stage is equipped with processing members that perform predetermined processes on the strip-shaped thin sheet F.

[0040] In other words, the processing components include: pilot hole punching stage I, equipped with a pilot hole punching punch 28 and a pilot hole punching die 68; slot punching stage II, equipped with a slot punching punch 30 and a slot punching die 70, a crimping part forming punch 32, a crimping part forming die 72 and a plate cam 38; internal shape punching stage IV, equipped with an internal shape punching punch 34 and an internal shape punching die 74; and external shape punching stage V, equipped with an external shape punching punch 36 and an external shape punching die 76.

[0041] Furthermore, the progressive die device 10 has an intermediate idle stage I1 between the inner die punching stage IV and the outer die punching stage V, and a final idle stage I2 on the forward (downstream) side of the outer die punching stage V in the transfer direction. In each idle stage I1 and I2, the strip-shaped thin sheet F is fed without any overhead.

[0042] As a result, the progressive die apparatus 10 is configured with a pilot hole punching stage I, a slot punching stage II, a crimping stage III, an inner shape punching stage IV, an intermediate idle stage I1, an outer shape punching stage V, and a final idle stage I2, arranged in sequence at predetermined intervals in the transport direction of the strip-shaped thin sheet F. The distance between the pilot hole punching stage I and the slot punching stage II is set to 1.5 times the transport pitch T of the strip-shaped thin sheet F, and the distance between adjacent stages is set to a value equal to the transport pitch T of the strip-shaped thin sheet F.

[0043] In the pilot hole punching stage I, a pilot punching process is performed by a plurality of pilot hole punching punches 28 and a plurality of pilot hole punching dies 68 corresponding to each pilot hole punching punch 28. With each press operation, that is, with each intermittent transfer of the strip-shaped sheet F, a plurality of circular pilot holes P are punched into the strip-shaped sheet F. The pilot holes P are formed along the vicinity of each of the left and right side edges of the strip-shaped sheet F, aligned in the direction of transfer of the strip-shaped sheet F (see Figure 2).

[0044] In slot punching stage II, the slot punching process is performed by a slot punching punch 30 and a slot punching die 70, and with each press operation, slots S (see Figure 2) are punched into the strip-shaped thin sheet F. The slots S are arranged at predetermined intervals in the circumferential direction and correspond to the areas between the multiple teeth C formed in the strip-shaped thin sheet F. The slot punching punch 30 and the slot punching die 70 are provided corresponding to each slot S.

[0045] In the crimping portion formation stage III, the crimping portion formation process is performed by the crimping portion forming punch 32 and the crimping portion forming die 72, and with each pressing operation, a crimping portion D (see Figure 2) is embossed onto the strip-shaped thin sheet F. The crimping portions D are arranged at predetermined intervals in the circumferential direction of the yoke portion B. Each crimping portion D has a convex shape on one side of the strip-shaped thin sheet F and a concave shape on the opposite side, and in the outer shape punching stage V described later, it crimps and joins adjacent stacked iron core thin sheets A together.

[0046] The laminated iron core is composed of a predetermined number of iron core thin sheets A that are crimped together. When manufacturing more than a predetermined number of iron core thin sheets A using the progressive die device 10, the plate cam 38 moves in a direction that increases the effective length of the crimping portion forming punch 32 each time a predetermined number of iron core thin sheets A are manufactured. In other words, when weighing to set the number of laminated iron core thin sheets A, the plate cam 38 moves in a direction that increases the effective length of the crimping portion forming punch 32, thereby increasing the effective length of the crimping portion forming punch 32 for punching.

[0047] In this state, the crimping punch 32 and the crimping die 72 form through holes in the iron core sheet A instead of embossing. As a result, the iron core sheets A that are stacked in the outer shape punching stage V described later are not crimped together, and a predetermined number of crimped stacked iron cores are continuously manufactured.

[0048] In the internal die-cutting stage IV, the internal die-cutting process is performed by the internal die-cutting punch 34 and the internal die-cutting die 74, and with each press operation, a circular internal shape G (see Figure 2) is punched out of the strip-shaped sheet F. As a result, multiple teeth C (including the part that defines the inner edge) are punched out of the strip-shaped sheet F with each press operation.

[0049] In the outer shape punching stage V, the outer shape punching process is performed by the outer shape punching punch 36 and the outer shape punching die 76, and with each press operation, a circular outer shape H (see Figure 2) is punched out of the strip-shaped thin sheet F. As a result, one iron core sheet A is punched out from the strip-shaped thin sheet F.

[0050] The iron core sheet A, completed by punching out the outer shape H, is pressed into the outer shape punching die 76 by the outer shape punching punch 36, and is sequentially stacked on top of the iron core sheets A that were punched out earlier within the outer shape punching die 76. Multiple iron core sheets A stacked within the outer shape punching die 76 are joined to each other by the crimping portion D.

[0051] In the outer shape punching stage V, when the upper die 20 descends at the start of punching the outer shape H, the stripper 40 descends together with the upper die 20. At this time, the strip-shaped thin sheet F is in a state of virtual stillness when not being transported (including cases where it is not strictly stopped). As the stripper 40 descends, its lower surface presses the upper surface of the strip-shaped thin sheet F downwards. At this time, the strip-shaped thin sheet F is held between the lower surface of the stripper 40 and the upper surface of the lower die 60.

[0052] When the upper die 20 rises after the punching of the outer shape H is complete, the stripper 40 rises together with the upper die 20. As a result, the pressure of the stripper 40 on the strip-shaped sheet F is released, and the strip-shaped sheet F is separated from the upper surface of the lower die 60. In this state, the strip-shaped sheet F is conveyed in the forward direction by a predetermined feed amount.

[0053] Furthermore, the operation of the stripper 40 is the same in other stages of Stage IV.

[0054] As shown in Figure 4, pilot pins 80 are attached to each stage II-V, I1, and I2 after stage I in the upper mold 20. Each pilot pin 80 engages with the corresponding pilot hole P in each stage II-V, I1, and I2 to position the strip-shaped thin plate F in each stage II-V, I1, and I2.

[0055] As shown in Figure 4, pilot pins 80 are attached to the punch plate 26 for each stage I-V, I1, and I2, and are spring-biased downward by compression coil springs 82. The pilot pins 80 are located near the left and right side edges Fa and Fb of the strip-shaped thin plate F. To correspond to the pilot holes P, the pilot pins 80 on both the left and right sides of the punch plate 26 pass through pin through holes 84 formed in the stripper 40 and are exposed toward the upper surface of the die plate 64.

[0056] The pilot pin 80 penetrates the pilot hole P in the strip-shaped thin plate F as the upper die 20 descends and engages with the pilot pin receiving hole 86 formed in the die plate 64. This engagement positions the strip-shaped thin plate F relative to the progressive die device 10.

[0057] Next, we will explain the formation of multiple pilot holes P in pilot hole punching stage I and the arrangement of pilot pins 80 in each stage II to V, I1, and I2 after stage I.

[0058] As shown in Figure 3, the pilot hole punching punch 28 and pilot hole punching die 68 in the pilot hole punching stage I are provided in pairs, aligned in the direction of transport of the strip-shaped thin sheet F, at positions corresponding to the vicinity of the left and right side edges Fa and Fb of the strip-shaped thin sheet F, respectively.

[0059] As a result, as shown in Figure 2, two pilot holes P are formed near each side edge Fa and Fb of the strip-shaped thin plate F, aligned in the direction of transport, with each transport of the strip-shaped thin plate F. For the sake of explanation, the pilot hole P on the front side (advancing side) in the transport direction is sometimes called the front pilot hole Pa, and the pilot hole P on the rear side (lagging side) in the transport direction is sometimes called the rear pilot hole Pb.

[0060] The front pilot hole Pa and rear pilot hole Pb are pilot holes formed for each transfer, and the front pilot hole Pa and rear pilot hole Pb in the same row are formed at a predetermined interval smaller than the transfer pitch T in the transfer direction of the strip-shaped thin plate F. A pair of front pilot holes Pa and rear pilot holes Pb are provided in each stage II to V, one in front of the arrangement position of the processing member in each stage II to V. In other words, a pair of front pilot holes Pa and rear pilot holes Pb are formed in each stage II to V, at two locations separated from the processing member in each stage II to V in the transfer direction of the strip-shaped thin plate F. The pair of front pilot holes Pa and rear pilot holes Pb in front of the arrangement position of the processing member is called the front pair, and the pair of front pilot holes Pa and rear pilot holes Pb behind the arrangement position of the processing member is called the rear pair.

[0061] The pilot pin 80 is positioned to use the front pilot hole Pa of the two pilot holes P in one of stages II to V, and to use the rear pilot hole Pb of the two pilot holes P in another of stages II to V. In other words, in one of stages II to V, the pilot pin 80 is positioned to engage with one of the two pilot holes P, and in another of stages II to V, the pilot pin 80 is positioned to engage with the other of the two pilot holes P. As a result, in at least one of stages II to V, there is at least one pilot hole P that does not engage with the pilot pin 80.

[0062] This specific example will be explained using the strip layout (single row) shown in Figure 2. In Figure 2, pilot holes P into which the pilot pin 80 engages are indicated by circles with cross marks, while unused pilot holes P into which the pilot pin 80 does not engage are indicated by open circles.

[0063] In slot punching stage II, the pilot pin 80 engages with the rear pilot hole Pb in both the front and rear pairs, but does not engage with the front pilot hole Pa. In other words, the front pilot hole Pa is unused.

[0064] From the viewpoint of performing slot punching with high precision, it is preferable that the pilot pin 80 engages with a pilot hole P formed at the position closest to the processing member (slot punching punch 30 and slot punching die 70) without interfering with the processing member. From this viewpoint, in the slot punching stage II, it is preferable that the pilot pin 80 engages with the rear pilot hole Pb in the front pair and with the front pilot hole Pa in the rear pair.

[0065] However, as an exception, since it is preferable that the pilot hole P into which the pilot pin 80 engages immediately after the formation of the pilot hole P is closer to the pilot hole punching stage I, in this embodiment, in the rear pair of slot punching stage II, which is the next stage after the pilot hole punching stage I, the pilot pin 80 engages with the rear pilot hole Pb, which is closer to the pilot hole punching stage I than the front pilot hole Pa.

[0066] In the crimping stage III, the pilot pin 80 engages with a pilot hole located away from the plate cam 38 (processing member) so as not to interfere with the plate cam 38. Specifically, in the front pair, the pilot pin 80 engages with the front pilot hole Pa, and in the rear pair, the pilot pin 80 engages with the rear pilot hole Pb.

[0067] In the internal die punching stage IV, to ensure high-precision internal die punching, the pilot pin 80 engages with the pilot hole located close to the processing material (internal die punch 34 and internal die punch 74). Specifically, in the front pair, the pilot pin 80 engages with the rear pilot hole Pb, and in the rear pair, the pilot pin 80 engages with the front pilot hole Pa.

[0068] In the outer shape punching stage V, the pilot pin 80 engages with a pilot hole located away from the outer shape punching die 76 (processing member), which is a rotating die. Specifically, in the front pair, the pilot pin 80 engages with the front pilot hole Pa, and in the rear pair, the pilot pin 80 engages with the rear pilot hole Pb.

[0069] Furthermore, in the intermediate idle stage I1, the pilot pin 80 engages with the rear pilot hole Pb in both the front and rear pairs. In addition, in the final idle stage I2, the pilot pin 80 engages with the rear pilot hole Pb in the front pair, and in the final idle stage I2, the pilot pin 80 engages with the front pilot hole Pa in the rear pair.

[0070] In each stage, the pilot pins 80 are positioned such that they engage with the front pilot hole Pa or rear pilot hole Pb described above. This increases the degree of freedom in the positioning of the pilot holes P with respect to the transport direction of the strip-shaped thin plate F, and consequently increases the degree of freedom in the positioning of the pilot pins 80 with respect to the transport direction of the strip-shaped thin plate F.

[0071] This allows the pilot pin 80 to be easily positioned so as not to interfere with the plate cam 38 or the rotating die, which is the outer die 76 for punching out shapes.

[0072] In other words, even if one of the front pilot hole Pa and the rear pilot hole Pb is formed in a position that interferes with a processing member of a certain processing stage, such as the plate cam 38 or the die 76 for punching out the outer shape, the pilot pin 80 does not engage with the front pilot hole Pa or the rear pilot hole Pb that is in the interfering position, and the pilot pin 80 engages with the other front pilot hole Pa or the rear pilot hole Pb that is formed in a position that does not interfere. As a result, the role of the pilot hole P is fulfilled in each processing stage without complicating the structure of the plate cam 38 or the die 76 for punching out the outer shape.

[0073] This enables the repeated production of high-precision iron core sheets A under proper positioning of the strip-shaped sheet F relative to the progressive die device 10 based on the engagement of the pilot hole P and the pilot pin 80.

[0074] Figure 5 shows the strip layout for a two-row configuration. In the two-row configuration, the multiple processing stages shown in Figure 2 are arranged in two rows, left and right. In each stage of the left and right rows, the front pilot holes Pa or rear pilot holes Pb used are biased in the transport direction, with one located on the left side edge Fa of the strip F and the other on the right side edge Fb. In Figure 5, pilot holes that are used and engaged by the pilot pin 80 are indicated by circles with cross marks, while unused pilot holes that are not engaged by the pilot pin 80 are indicated by open circles.

[0075] Therefore, in the case of two rows, as in the case of one row, the pilot pins 80 of each stage are positioned to engage with the front pilot hole Pa or the rear pilot hole Pb described above at each stage.

[0076] As a result, even in the case of two rows, the degree of freedom in the positioning of the pilot hole P into which the pilot pin 80 engages is increased with respect to the transport direction of the strip-shaped thin plate F.

[0077] (Embodiment 2) Embodiment 2 will be described with reference to Figures 6 and 7. In Embodiment 2, parts that are substantially the same as those in Embodiment 1 will be denoted by the same reference numerals as in Embodiment 1.

[0078] In Embodiment 2, the laminated iron core sheets A are joined by adhesive. The iron core sheets A used in Embodiment 2 do not have the crimped portion D of Embodiment 1, and the portion corresponding to the crimped portion D becomes the adhesive point J (see Figure 6). The iron core sheets A of Embodiment 2 differ from those of Embodiment 1 in terms of the crimped portion D and the adhesive point J, but the other components are the same as those of the iron core sheets A of Embodiment 1 shown in Figure 1, so for convenience, they will be described using the same reference numerals as the iron core sheets A of Embodiment 1.

[0079] The manufacturing process for the iron core sheet A involves the following steps being performed in order, as shown in Figure 6: a pilot hole punching step (I) to punch out pilot holes P, a slit punching step (II) to punch out slots S between adjacent tooth portions C, an internal shape punching step (III) to punch out circular internal shapes G to define the tips of the tooth portions C, an adhesive application step (IV) to apply adhesive to each bonding point J of the strip sheet F (yoke portion B), and an external shape punching step (V) to punch out the circular external shape H of the yoke portion B.

[0080] In this embodiment, each bonding point J is located on the lower surface of the strip-shaped thin plate F, since the adhesive application device 90, which will be described later, is positioned below the strip-shaped thin plate F. For this reason, each bonding point J should be shown by a hidden line (dashed line) in Figure 6 (top view), but it is shown in black to make it easier to see where the adhesive has been applied.

[0081] Next, the progressive die apparatus 10 of Embodiment 1 will be described with reference to Figure 7. The progressive die apparatus 10 comprises an upper die 20 and a lower die 60 arranged to sandwich a strip-shaped thin plate F from above and below.

[0082] The upper die 20 has a plate-shaped upper holder 22 that is fixed to the lower surface of the upper ram (not shown) of the press machine. This allows the upper die 20 to move vertically to approach and move away from the lower die 60. In the upper die 20, a backing plate 24 and a punch plate 26 are attached to the lower part of the upper holder 22. The punch plate 26 fixes a pilot hole punch 28, a slot punch 30, an inner shape punch 34, and an outer shape punch 36 to the upper holder 22, respectively.

[0083] In the upper mold 20, a stripper 40 is attached below the upper holder 22. The stripper 40 is displaceable in the vertical direction relative to the upper holder 22. The lowest position of the stripper 40 relative to the upper holder 22 is set by suspension support by suspension bolts (not shown). The stripper 40 is constructed as a joint between a stripper body 40A and a stripper 40B, each having a plate-like shape.

[0084] The lower surface of the stripper 40 faces the upper surface of the die plate 64 and each die 68, 70, 74, and 76, which will be described later. The stripper 40 has punch through holes 42, 44, 48, and 50 through which each punch 28, 30, 34, and 36 passes.

[0085] The lower die 60 has a plate-shaped lower holder 62 fixed to the upper surface of the lower bolster (not shown) of the press machine. The lower holder 62 is positioned opposite the upper holder 22. In the lower die 60, a plate-shaped die plate 64 is attached to the upper surface of the lower holder 62. A die 68 for punching pilot holes, a die 70 for punching slots, a die 74 for punching inner shapes, an adhesive application device 90, and a die 76 for punching outer shapes are attached to the die plate 64. The die 76 for punching outer shapes is cylindrical and constitutes a rotating die that rotates in segments around its central axis at a predetermined rotation angle.

[0086] Each punch 28, 30, 34, and 36 corresponds to each die 68, 70, 74, and 76, forming individual processing stages spaced apart from each other in the transport direction of the strip-shaped thin sheet F. The processing stages consist of a pilot hole punching stage (pilot hole forming section) I formed by the pilot hole punching punch 28 and the pilot hole punching die 68, a slot punching stage II formed by the slot punching punch 30 and the slot punching die 70, an internal shape punching stage III formed by the internal shape punching punch 34 and the internal shape punching die 74, and an external shape punching stage V formed by the external shape punching punch 36 and the external shape punching die 76. Between the internal shape punching stage III and the external shape punching stage V, an adhesive application stage IV is formed by the adhesive application device 90.

[0087] The slot punching stage II, the internal die punching stage IV, the adhesive application stage IV, and the external die punching stage V are processing stages that perform predetermined processes in the progressive die device 10. The punches 28, 30, 34, 36, dies 68, 70, 74, 76, and adhesive application device 90 provided in each of the stages II to V constitute processing members that perform predetermined processes on the strip-shaped thin sheet F in each of the processing stages described above. Thus, each processing stage is equipped with processing members that perform predetermined processes on the strip-shaped thin sheet F.

[0088] In other words, the processing components include: pilot hole punching stage I, equipped with a pilot hole punching punch 28 and a pilot hole punching die 68; slot punching stage II, equipped with a slot punching punch 30 and a slot punching die 70; internal shape punching stage III, equipped with an internal shape punching punch 34 and an internal shape punching die 74; adhesive application stage IV, equipped with an adhesive application device 90; and external shape punching stage V, equipped with an external shape punching punch 36 and an external shape punching die 76.

[0089] Furthermore, the progressive die device 10 has an intermediate idle stage I1 between the adhesive application stage IV and the outer shape punching stage V, and a final idle stage I2 on the forward (downstream) side of the outer shape punching stage V in the transfer direction. In each idle stage I1 and I2, the strip-shaped thin sheet F is fed without any overhead.

[0090] As a result, the progressive die apparatus 10 is configured with a pilot hole punching stage I, a slot punching stage II, an inner shape punching stage III, an adhesive application stage IV, an intermediate idle stage I1, an outer shape punching stage V, and a final idle stage I2, arranged in sequence at predetermined intervals in the transport direction of the strip-shaped thin sheet F. The distance between the pilot hole punching stage I and the slot punching stage II is set to 1.5 times the transport pitch T of the strip-shaped thin sheet F, and the distance between adjacent stages is set to a value equal to the transport pitch T of the strip-shaped thin sheet F.

[0091] In the pilot hole punching stage I, a pilot punching process is performed by a plurality of pilot hole punching punches 28 and a plurality of pilot hole punching dies 68 corresponding to each pilot hole punching punch 28. With each press operation, that is, with each intermittent transfer of the strip-shaped sheet F, a plurality of circular pilot holes P are punched into the strip-shaped sheet F. The pilot holes P are formed along the vicinity of each of the left and right side edges of the strip-shaped sheet F, aligned in the direction of transfer of the strip-shaped sheet F (see Figure 6).

[0092] In slot punching stage II, the slot punching process is performed by a slot punching punch 30 and a slot punching die 70, and with each press operation, slots S (see Figure 6) are punched into the strip-shaped thin sheet F. The slots S are arranged at predetermined intervals in the circumferential direction and correspond to the areas between the multiple teeth C formed in the strip-shaped thin sheet F. The slot punching punch 30 and the slot punching die 70 are provided corresponding to each slot S.

[0093] In the internal die-cutting stage III, the internal die-cutting process is performed by the internal die-cutting punch 34 and the internal die-cutting die 74, and with each press operation, a circular internal shape G (see Figure 6) is punched out of the strip-shaped sheet F. As a result, multiple teeth C (including the part that defines the inner edge) are punched out of the strip-shaped sheet F with each press operation.

[0094] In adhesive application stage IV, adhesive application is performed by the adhesive application device 90.

[0095] The adhesive application device 90 has an upper block 92 and a lower block 94 that are integrally joined together. The upper block 92 and the lower block 94 cooperate to define an adhesive reservoir chamber 96. Liquid adhesive pressurized to a predetermined pressure is supplied to the adhesive reservoir chamber 96 from an adhesive passage 98 formed in the lower block 94. Multiple adhesive discharge ports 100 that communicate with the adhesive reservoir chamber 96 are formed through the upper wall of the upper block 92. Each of the multiple adhesive discharge ports 100 opens onto the flat upper surface of the upper block 92. The adhesive supplied to the adhesive reservoir chamber 96 has a predetermined viscosity, which causes each adhesive discharge port 100 to form a substantially hemispherical raised portion K that rises upward from the opening end relative to the upper surface of the upper block 92.

[0096] The joint between the upper block 92 and the lower block 94 is slidably engaged in the lower holder 62 and the block receiving hole 102 formed in the die plate 64 so as to be vertical. A plate cam 106 including a sawtooth-shaped cam portion 104 is provided on the lower side of the lower holder 62 so as to be movable in the left-right direction as seen in Figure 7. A sawtooth-shaped cam portion 108 corresponding to the cam portion 104 is formed on the lower surface of the lower block 94. Due to the movement of the plate cam 106, the joint between the upper block 92 and the lower block 94 moves between a raised position where the upper surface of the upper block 92 is approximately flush with the upper surface of the die plate 64 or slightly below the upper surface of the die plate 64, and a lowered position below the raised position, as shown in Figure 7.

[0097] The joint between the upper block 92 and the lower block 94 is in the raised position except when weighing to set the number of layers of iron core sheets A. In this raised position, the adhesive on the raised portion K comes into contact with the lower surface of the strip-shaped sheet F as the strip-shaped sheet F descends toward the upper surface of the die plate 64 due to the lowering of the stripper 40, and is transferred. Thus, adhesive is applied to each bonding point J of the strip-shaped sheet F. When weighing to set the number of layers of iron core sheets A, the joint between the upper block 92 and the lower block 94 is in the lowered position, so even when the strip-shaped sheet F descends toward the upper surface of the die plate 64, the adhesive on the raised portion K does not come into contact with the lower surface of the strip-shaped sheet F, and therefore no adhesive is applied to the strip-shaped sheet F.

[0098] In the outer shape punching stage V, the outer shape punching process is performed by the outer shape punching punch 36 and the outer shape punching die 76, and with each press operation, a circular outer shape H (see Figure 2) is punched out of the strip-shaped thin sheet F. As a result, one iron core sheet A is punched out from the strip-shaped thin sheet F.

[0099] The iron core sheet A, completed by punching out the outer shape H, is pressed into the outer shape punching die 76 by the outer shape punching punch 36, and is sequentially stacked on top of the iron core sheets A that were punched out earlier within the outer shape punching die 76. The multiple iron core sheets A stacked within the outer shape punching die 76 are bonded (joined) together by adhesive at each bonding point J.

[0100] In the outer shape punching stage V, when the upper die 20 descends at the start of punching the outer shape H, the stripper 40 descends together with the upper die 20. At this time, the strip-shaped thin sheet F is in a state of virtual stillness when not being transported (including cases where it is not strictly stopped). As the stripper 40 descends, its lower surface presses the upper surface of the strip-shaped thin sheet F downwards. At this time, the strip-shaped thin sheet F is held between the lower surface of the stripper 40 and the upper surface of the lower die 60.

[0101] When the upper die 20 rises after the punching of the outer shape H is complete, the stripper 40 rises together with the upper die 20. As a result, the pressure of the stripper 40 on the strip-shaped sheet F is released, and the strip-shaped sheet F is separated from the upper surface of the lower die 60. In this state, the strip-shaped sheet F is conveyed in the forward direction by a predetermined feed amount.

[0102] Furthermore, the operation of the stripper 40 is the same in other stages of Stage IV.

[0103] As shown in Figure 4, pilot pins 80 are attached to each stage II-V, I1, and I2 after stage I in the upper mold 20. Each pilot pin 80 engages with the corresponding pilot hole P in each stage II-V, I1, and I2 to position the strip-shaped thin plate F in each stage II-V, I1, and I2.

[0104] In Embodiment 2, as in Embodiment 1, pilot pins 80 are attached to the punch plate 26 for each stage I-V, I1, and I2, as shown in Figure 4, and are spring-biased downward by compression coil springs 82. The pilot pins 80 are located near the left and right side edges Fa and Fb of the strip-shaped thin plate F. To correspond to the pilot holes P, the pilot pins 80 on both the left and right sides of the punch plate 26 pass through pin through holes 84 formed in the stripper 40 and are exposed toward the upper surface of the die plate 64.

[0105] The pilot pin 80 penetrates the pilot hole P in the strip-shaped thin plate F as the upper die 20 descends and engages with the pilot pin receiving hole 86 formed in the die plate 64. This engagement positions the strip-shaped thin plate F relative to the progressive die device 10.

[0106] Next, we will explain the formation of multiple pilot holes P in pilot hole punching stage I and the arrangement of pilot pins 80 in each stage II to V, I1, and I2 after stage I.

[0107] As shown in Figure 7, the pilot hole punching punch 28 and pilot hole punching die 68 in the pilot hole punching stage I are provided in pairs, aligned in the direction of transport of the strip-shaped thin plate F, at positions corresponding to the vicinity of the left and right side edges Fa and Fb of the strip-shaped thin plate F, respectively.

[0108] As a result, as shown in Figure 6, two pilot holes P are formed near each side edge Fa and Fb of the strip-shaped thin plate F, aligned in the direction of transport, for each transport of the strip-shaped thin plate F. Here, in Embodiment 2 as well, for the sake of explanation, the pilot hole P on the front side (advancing side) in the transport direction of the two pilot holes P may be called the front pilot hole Pa, and the pilot hole P on the rear side (lagging side) in the transport direction of the two pilot holes P may be called the rear pilot hole Pb.

[0109] The front pilot hole Pa and the rear pilot hole Pb are pilot holes formed for each transfer, and the front pilot hole Pa and the rear pilot hole Pb in the same row are formed at a predetermined interval smaller than the transfer pitch T in the transfer direction of the strip-shaped thin plate F. The pair of front pilot hole Pa and rear pilot hole Pb is provided in each stage II to V, in front of and behind the placement position of the processing member in each stage II to V. In other words, the pair of front pilot hole Pa and rear pilot hole Pb is formed in two locations in each stage II to V, separated from the processing member in each stage II to V in the transfer direction of the strip-shaped thin plate F. In Embodiment 2 as well, the pair of front pilot hole Pa and rear pilot hole Pb in front of the placement position of the processing member is called the front pair, and the pair of front pilot hole Pa and rear pilot hole Pb behind the placement position of the processing member is called the rear pair.

[0110] The pilot pin 80 is positioned to use the front pilot hole Pa of the two pilot holes P in one of stages II to V, and to use the rear pilot hole Pb of the two pilot holes P in another of stages II to V. In other words, in one of stages II to V, the pilot pin 80 is positioned to engage with one of the two pilot holes P, and in another of stages II to V, the pilot pin 80 is positioned to engage with the other of the two pilot holes P. As a result, in at least one of stages II to V, there is at least one pilot hole P that does not engage with the pilot pin 80.

[0111] This specific example will be explained using the strip layout (single row) shown in Figure 6. In Figure 6, pilot holes P that engage with the pilot pin 80 are indicated by circles with cross marks, while unused pilot holes P that do not engage with the pilot pin 80 are indicated by open circles.

[0112] In slot punching stage II, the pilot pin 80 engages with the rear pilot hole Pb in both the front and rear pairs, but does not engage with the front pilot hole Pa. In other words, the front pilot hole Pa is unused.

[0113] In the internal die-cutting stage III, to ensure high-precision internal die-cutting, the pilot pin 80 engages with a pilot hole located close to the processing material (internal die-cutting punch 34 and internal die-cutting die 74). Specifically, in the front pair, the pilot pin 80 engages with the rear pilot hole Pb, and in the rear pair, the pilot pin 80 engages with the front pilot hole Pa.

[0114] Furthermore, the front pair of slot punching stage II, which is located between slot punching stage II and internal shape punching stage III, forms a rear pair in internal shape punching stage III. In the front pair of slot punching stage II, in other words, in the rear pair of internal shape punching stage III, the pilot pin 80 engages with both the front pilot hole Pa and the rear pilot hole Pb.

[0115] In adhesive application stage IV, to prevent the pilot pin 80 from interfering with the adhesive application device 90 (processing member), the pilot pin 80 engages with a pilot hole located away from the adhesive application device 90; that is, in the front pair, the pilot pin 80 engages with the front pilot hole Pa, and in the rear pair, the pilot pin 80 engages with the rear pilot hole Pb.

[0116] In the outer shape punching stage V, the pilot pin 80 engages with a pilot hole located away from the outer shape punching die 76 (processing member), which is a rotating die. Specifically, in the front pair, the pilot pin 80 engages with the front pilot hole Pa, and in the rear pair, the pilot pin 80 engages with the rear pilot hole Pb.

[0117] In the intermediate idle stage I1 and the final idle stage I2, in order to suppress vibrations of the strip-shaped thin plate F due to processing impacts, the pilot pin 80 engages with the pilot hole on the side where the separation distance in the transport direction of the strip-shaped thin plate F is shorter in the front pair and rear pair of pilot holes, i.e., the rear pilot hole Pb in the front pair and the front pilot hole Pa in the rear pair.

[0118] In each stage, the pilot pins 80 are positioned such that they engage with the front pilot hole Pa or rear pilot hole Pb described above. This increases the degree of freedom in the positioning of the pilot holes P with respect to the transport direction of the strip-shaped thin plate F. Consequently, the degree of freedom in the positioning of the pilot pins 80 is increased with respect to the transport direction of the strip-shaped thin plate F.

[0119] This allows the pilot pin 80 to be easily positioned so as not to interfere with the adhesive application device 90 or the rotating die, which is the outer die 76 for punching out shapes.

[0120] In other words, even if one of the front pilot hole Pa and the rear pilot hole Pb is formed in a position that interferes with a processing member of a certain processing stage, such as an adhesive application device 90 or an outer shape punching die 76, the pilot pin 80 does not engage with the front pilot hole Pa or the rear pilot hole Pb that is in the interfering position, and the pilot pin 80 engages with the other front pilot hole Pa or the rear pilot hole Pb that is formed in a non-interfering position. As a result, the role of the pilot hole P is fulfilled in each processing stage without complicating the structure of the plate cam 38 or the outer shape punching die 76.

[0121] As a result, in Embodiment 2, as in Embodiment 1, high-precision iron core sheets A can be repeatedly manufactured under the proper positioning of the strip-shaped sheet F relative to the progressive die device 10 based on the engagement of the pilot hole P and the pilot pin 80.

[0122] Furthermore, in Embodiment 2, it is possible to apply a two-row setup, similar to Embodiment 1.

[0123] Although the present invention has been described above in terms of preferred embodiments, as will be easily understood by those skilled in the art, the present invention is not limited to these embodiments and can be modified as appropriate without departing from the spirit of the invention. For example, the front pilot hole Pa and the rear pilot hole Pb on the same side may be offset from each other in the lateral width direction of the strip-shaped thin plate F. The number of pilot holes P in each row punched out for each transfer of the strip-shaped thin plate F in intermittent transfer is not limited to two, and may be three or more, as long as it is within the range of one transfer pitch T.

[0124] The pilot pin 80 and pilot hole P are not limited to the vicinity of the left and right side edges of the strip-shaped thin plate F, but may also be located in a position that does not interfere with the processing member between the left and right side edges. In each processing stage, the pilot hole P into which the pilot pin 80 engages may be different on the left side edge Fa side and the right side edge Fb side of the strip-shaped thin plate F. For example, the side edge Fa side may be designated as the rear pilot hole Pb, and the side edge Fb side as the front pilot hole Pa. [Explanation of Symbols]

[0125] 10: Progressive die machine 20: Upper mold 22: Upper holder 24: Backing Plate 26: Punch Plate 28: Punch for punching pilot holes 30: Punch for punching slots 32: Punch for forming crimped section 34: Punch for punching out internal shapes 36: Punch for cutting out external shapes 38: Plate Cam 40: Strippers 40A: Stripper body 40B: Stripper 42: Punched through hole 44: Punched hole 46: Punched hole 48: Punched hole 50: Punch through hole 60: Lower mold 62: Lower holder 64: Die Plate 68: Die for punching pilot holes 70: Die for punching slots 72: Die for forming crimped section 74: Die for punching out internal shapes 76: Die for punching out external shapes 80: Pilot pin 82: Compression coil spring 84: Pin through hole 86: Pilot pin receiving hole 90: Adhesive application device 92: Upper block 94: Lower block 96: Adhesive accumulation room 98: Adhesive passage 100: Adhesive dispensing port 102: Block receiving hole 104: Cam section 106: Plate Cam 108: Cam section A: Thin iron core B: York section C: Teeth Department D: Crimping part F: Strip-shaped thin plate Fa: Side edge Fb: Side edge G: Internal shape H: External shape I: Pilot hole punching stage (Embodiment 1, 2) II: Slot punching stage (Embodiment 1, 2) III: Crimping stage (Embodiment 1) III: Internal shape punching stage (Embodiment 2) IV: Internal die-cutting stage (Embodiment 1) IV: Adhesive application stage (Embodiment 2) V: Outer shape punching stage (Embodiments 1 and 2) I1: Intermediate Idol Stage (Implementation 1, 2) I2: Final Idol Stage (Implementation Examples 1 and 2) J: Adhesion point K: The exciting part P: Pilot hole Pa: Front pilot hole Pb: Rear pilot hole S: Slot T: Transfer pitch

Claims

1. A progressive die device for manufacturing iron core sheets of a predetermined shape by performing predetermined processing on a strip-shaped thin plate that is intermittently transferred at a predetermined pitch in each of a plurality of processing stages that are aligned in the transfer direction of the strip-shaped thin plate, a pilot hole forming section that punches and forms a plurality of pilot holes in the strip-shaped thin plate for each transfer of the strip-shaped thin plate during intermittent transfer; at least one pilot pin provided corresponding to each of the processing stages, engaging with the corresponding pilot hole to position the strip-shaped thin plate in each of the processing stages; In one of the processing stages, the pilot pin is positioned to engage one of the plurality of pilot holes; In another one of the processing stages, the pilot pin is positioned to engage with one other of the plurality of pilot holes.

2. 2. The progressive die device according to claim 1, wherein the pilot hole forming section is configured so that the plurality of pilot holes are aligned in the transfer direction.

3. 2. The progressive die device according to claim 1, wherein the pilot hole forming section is configured so that the plurality of pilot holes are aligned along each of the side edges of the strip-shaped thin plate in the conveying direction.

4. Each of the processing stages is provided with a processing member for performing a predetermined processing on the strip-shaped thin plate, A progressive die device described in any one of claims 1 to 3, wherein the pilot pin engages with one of the plurality of pilot holes formed at multiple locations in each of the processing stages, spaced apart in the transport direction, that does not interfere with the processing member.

5. A progressive die device as described in claim 4, wherein one of the processing stages is a crimping portion forming stage equipped with a crimping portion forming punch and a crimping portion forming die that form a crimping portion in the strip-shaped thin plate, and a cam that increases or decreases the effective length of the crimping portion forming punch, and the processing member that is subject to interference with the pilot pin is the cam.

6. 5. A progressive die device as described in claim 4, wherein one of the processing stages is an adhesive application stage equipped with an adhesive application device that applies adhesive to the strip-shaped thin plate, and the processing member that is subject to interference with the pilot pin is the adhesive application device.

7. 5. The progressive die device according to claim 4, wherein one of the processing stages comprises a punching stage equipped with a punch and a rotary die, and the processing member that is subject to interference with the pilot pin is the rotary die.

8. A manufacturing method for manufacturing iron core thin plates of a predetermined shape by subjecting a strip-shaped thin plate, which is intermittently transported at a predetermined pitch, to predetermined processing in each of a plurality of processing stages set by a progressive die device in alignment in the transport direction of the strip-shaped thin plate, comprising: a pilot hole forming section punching and forming a plurality of pilot holes for each transfer of the strip-shaped thin plate during intermittent transfer; At least one pilot pin is provided corresponding to each of the processing stages, and engages with the corresponding pilot hole to position the strip-shaped thin plate in each of the processing stages; A method for manufacturing an iron core sheet, wherein the pilot pin engages with one of the plurality of pilot holes in one of the processing stages, and engages with one of the plurality of pilot holes other than the one in another of the processing stages.

9. The method for manufacturing an iron core thin plate according to claim 8 , wherein the plurality of pilot holes are aligned in the direction of transfer.