More core manufacturing method

Abstract

To provide a motor core manufacturing method with which it is possible to easily reduce the unevenness in dimensional accuracy of a motor core and, hence, the unevenness in motor performance.SOLUTION: The motor core manufacturing method comprises a block formation step, a detection step, and a laminate formation step. In the block formation step, a core piece is punched out from a sheet-like workpiece W by each of a plurality of progressive press devices 30, and a plurality of punched out core pieces are laminated for each progressive press device to form a block 15. In the block formation step, furthermore, an identification part 29 for identifying a progressive press device that formed a block is formed for only the top end face of a second core piece 25 constituting the top end face of the block. In the detection step, the identification part is detected by an imaging unit prior to the laminate formation step. In the laminate formation step, a laminate is formed by laminating only a block formed by a progressive press device corresponding to the detected identification part.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a motor core.

Background Art

[0002] Patent Document 1 describes a method for manufacturing a motor core formed by laminating a plurality of blocks. The method for manufacturing a motor core described in Patent Document 1 includes a block forming step of punching a plurality of core pieces from a base material made of an electromagnetic steel sheet and laminating the punched core pieces to form a block, and a laminate forming step of laminating a plurality of blocks.

[0003] In the block forming step, a progressive press device including a lower die and an upper die and punching the core pieces step by step is used. The lower die is provided with a plurality of punching dies having shapes corresponding to the punching portions of the core pieces at each stage. Further, a plurality of punching dies are provided on the upper die corresponding to the plurality of punching dies of the lower die, respectively. By the cooperation of the punching die of the lower die and the punching die of the upper die, the core pieces are punched from the base material.

[0004] In the progressive press device described in Patent Document 1, two rows of punching dies of the lower die and the upper die are provided in the width direction of the base material. As a result, two blocks are simultaneously formed from a common base material.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] By the way, in such a progressive press device, since the center of the punching die for punching the outer peripheral shape of the core piece and the center of the punching die for punching the inner peripheral shape of the core piece are slightly displaced, the center of the outer peripheral edge of the core piece and the center of the center hole are displaced.

[0007] In a progressive press device including a punching die of a plurality of lower dies and a punching die of an upper die as in Patent Document 1, the tendency of the displacement between the center of the outer peripheral edge of the core piece and the center of the center hole is different for each column. For this reason, when a plurality of blocks formed in different columns are mixed and laminated in the laminate forming step, the following inconveniences may occur. That is, when the blocks are laminated so that the centers of the center holes of the plurality of blocks coincide, the positions of the outer peripheral edges of the core pieces vary from block to block. As a result, problems such as the dimensional accuracy of the motor core and thus the variation in the performance of the motor are likely to increase.

Means for Solving the Problems

[0008] A method for manufacturing a motor core for solving the above problems includes a block forming step of punching core pieces from a thin plate-shaped workpiece by a plurality of progressive press devices and forming blocks by laminating the plurality of punched core pieces for each of the progressive press devices, and a laminate forming step of forming a laminate by laminating the plurality of blocks. In the block forming step, an identification portion for identifying the progressive press device that formed the block is formed only on one end surface of the core piece that constitutes one end surface of the block. Prior to the laminate forming step, a detection step of detecting the identification portion by a detection device is provided. In the laminate forming step, the laminate is formed by laminating only the blocks formed by the progressive press device corresponding to the detected identification portion.

[0009] According to the method, it is possible to prevent a plurality of blocks formed by different progressive press devices among the plurality of progressive press devices from being mixed in one laminate. Further, since it is only necessary to form an identification unit for identifying the progressive press device that formed the block on only one end face of the core piece that constitutes one end face of the block, the number of core pieces for forming the identification unit is minimized. As a result, the locations where the block is changed due to the formation of the identification unit can be minimized.

[0010] Therefore, it is possible to easily reduce the dimensional accuracy of the motor core and, consequently, the variation in the performance of the motor.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0012] <First Embodiment> Hereinafter, with reference to FIGS. 1 to 6, a first embodiment in which the method for manufacturing a motor core is embodied as a method for manufacturing a stator core will be described.

[0013] <Stator Core 10> First, with reference to FIGS. 1 to 3, the configuration of the stator core 10 of the present embodiment will be described.

[0014] In each drawing, for convenience of explanation, a part of the configuration may be shown in an exaggerated or simplified manner. As shown in FIG. 1, the stator core 10 has a substantially cylindrical shape with a central hole 10a.

[0015] As shown in FIG. 3, the stator core 10 has a laminate 16 in which a plurality of blocks 15 are laminated. The block 15 is formed by laminating a plurality of core pieces 20 made of electromagnetic steel sheets. Hereinafter, the axial direction of the stator core 10 will be referred to as the lamination direction, the radial direction of the stator core 10 will be simply referred to as the radial direction, and the circumferential direction of the stator core 10 will be simply referred to as the circumferential direction for explanation.

[0016] As shown in FIG. 1, the stator core 10 has an annular yoke 11 and a plurality of teeth 12 that extend radially inward from the yoke 11 and are formed at intervals in the circumferential direction.

[0017] Between adjacent teeth 12 in the circumferential direction, a slot 13 is formed that opens radially inward and extends in the radial direction. <Core piece 20> As shown in FIG. 3, the plurality of core pieces 20 forming the block 15 include a plurality of first core pieces 21 that are continuously laminated and one second core piece 25 that is laminated on one side (the upper side in FIG. 3) of the plurality of first core pieces 21.

[0018] As shown in FIGS. 1 to 3, the first core piece 21 has dowels 22 that bulge toward the second core piece 25 side in the lamination direction. A plurality of dowels 22 are provided at intervals in the circumferential direction.

[0019] As shown in FIG. 3, adjacent first core pieces 21 in the lamination direction are joined by caulking the dowels 22 together. As shown in FIGS. 1 to 3, the second core piece 25 has a first through hole 26 and a second through hole 27 that penetrate the second core piece 25 in the stacking direction.

[0020] A dowel 22 of the first core piece 21 adjacent to the second core piece 25 is inserted into the first through hole 26. A plurality of first through holes 26 are provided at intervals in the circumferential direction, and are respectively provided at positions overlapping the dowel 22 in the stacking direction (see FIG. 1).

[0021] A plurality of second through holes 27 are provided at intervals in the circumferential direction. In the present embodiment, three second through holes 27 are formed at intervals of 120 degrees, that is, at rotationally symmetric positions, around the axis of the stator core 10. The second through hole 27 is preferably circular in plan view, for example.

[0022] <Manufacturing apparatus 100 for stator core 10> Next, the manufacturing apparatus 100 for the stator core 10 will be described. As shown in FIGS. 4 to 6, the manufacturing apparatus 100 includes a progressive press apparatus 30, an identification apparatus 70, a laminate forming apparatus 80, and a control apparatus 90.

[0023] <Progressive press apparatus 30> As shown in FIG. 4, the progressive press apparatus 30 stepwise presses a thin plate-shaped workpiece W conveyed in the conveying direction (the left-right direction in FIG. 4). The progressive press apparatus 30 punches out core pieces 20 from the workpiece W and forms a block 15 by stacking the plurality of punched-out core pieces 20.

[0024] Although not shown, in the present embodiment, two rows of progressive press apparatuses 30 are arranged in parallel with respect to the conveying direction. Specifically, the two rows of progressive press apparatuses 30 share a fixed table 31, a movable table 32, a lower die set 33, an upper die set 34, and a stripper plate 35.

[0025] The movable table 32 is configured to be movable up and down above the fixed table 31 by being driven by an actuator (not shown). The lower die set 33 is fixed to the upper surface of the fixed table 31. Above the upper surface of the lower die set 33, a thin plate-shaped workpiece W is intermittently conveyed.

[0026] The upper die set 34 is fixed to the lower surface of the movable table 32. The stripper plate 35 is located below the upper die set 34 and is connected to the upper die set 34 so as to be relatively displaceable in the vertical direction via an elastic member (not shown).

[0027] The core pieces 20 are respectively punched out from the workpiece W by the two-row progressive press device 30, and the block 15 is formed by stacking the plurality of punched core pieces 20 for each progressive press device 30.

[0028] Since the two-row progressive press devices 30 basically have the same configuration, the configuration of one row of the progressive press devices 30 will be described, and the description of the configuration of the other row of the progressive press devices 30 will be omitted.

[0029] In the progressive press device 30, a first hole punching die 40, a first press die 45, a second hole punching die 50, a third hole punching die 55, and a second press die 60 are provided in order from the upstream side (the left side in FIG. 4) in the conveying direction.

[0030] The first hole punching die 40 punches out the portion corresponding to the center hole 10a and the portion corresponding to the slot 13 from the workpiece W, and includes a first hole punching die 41 and a first hole punching punch 43. The first press die 45 forms the dowel 22 in the workpiece W, and includes a first press die 46 and a first press punch 48.

[0031] The second hole punching die 50 punches out the first through hole 26 from the workpiece W, and includes a second hole punching die 51 and a second hole punching punch 53. The third hole punching die 55 punches out the second through hole 27 from the workpiece W, and includes a third hole punching die 56 and a third hole punching punch 58.

[0032] Note that the third hole punching die 55 is provided only on one of the two-row progressive press devices 30 and is not provided on the other. The second press die 60 punches out the core pieces 20 from the workpiece W and forms the block 15 by laminating the plurality of punched core pieces 20, and includes a second press die 61, a squeezing ring 62, and a second press punch 63.

[0033] The dies 41, 46, 51, 56, 61 and the squeezing ring 62 are all fixed to the lower die set 33. The punches 43, 48, 53, 58, 63 are all fixed to the upper die set 34.

[0034] The second hole punching punch 53 is configured to be displaceable by a drive mechanism (not shown) between a retracted position where it does not punch out the first through hole 26 as the movable table 32 descends and a punching position where it punches out the first through hole 26 as the movable table 32 descends.

[0035] The third hole punching punch 58 is configured to be displaceable by a drive mechanism (not shown) between a retracted position where it does not punch out the second through hole 27 as the movable table 32 descends and a punching position where it punches out the second through hole 27 as the movable table 32 descends.

[0036] In this embodiment, the block 15 is formed such that the second core piece 25 having the second through hole 27 becomes the lower surface. Below the second press die 61, a conveying device 36 for conveying the block 15 pushed out downward from the inside of the squeezing ring 62 is provided.

[0037] After the block 15 is conveyed downstream by the conveying device 36, it is placed on an imaging table 71 described later by a robot arm (not shown). <Identification device 70> As shown in FIG. 5, the identification device 70 includes an imaging table 71 on which the block 15 is placed, an imaging unit 74 located above the imaging table 71, and an inversion mechanism 75 for inverting the block 15.

[0038] The imaging table 71 includes a base 72 and a placement portion 73 provided on the upper part of the base 72, rotatably supported with respect to the base 72, on which the block 15 is placed. The placement portion 73 is rotationally driven by a motor (not shown).

[0039] The imaging unit 74 images the upper end surface 15a of the block 15 placed on the imaging table 71 and is configured by a well-known camera. As described above, the block 15 is placed on the imaging table 71 with the second iron core piece 25 facing downward.

[0040] The inversion mechanism 75 inverts the block 15 so that the second iron core piece 25 faces upward, and includes a pair of clamping portions 76 that clamp the outer peripheral surface of the block 15 and a lifting mechanism (not shown in the figure) that raises and lowers the pair of clamping portions 76. The inversion mechanism 75 is configured to invert the block 15 up and down by rotating the pair of clamping portions 76 in a state where the block 15 is clamped.

[0041] In this embodiment, the imaging unit 74 corresponds to the detection device according to the present invention. <Laminated body forming device 80> As shown in FIG. 6, the laminated body forming device 80 is a device that forms a laminated body 16 by laminating a plurality of blocks 15, and includes a laminated plate 81 and a transfer unit 85.

[0042] The laminated plate 81 has a plate body 82 that is substantially square in plan view, a post portion 83 that protrudes upward from the center of the plate body 82, and a plurality of positioning pins (not shown in the figure) that are located on the outer peripheral side of the post portion 83 and protrude upward from the plate body 82.

[0043] The post portion 83 is inserted into the central hole 10a of the block 15. The positioning pin is inserted into a predetermined slot 13 of the block 15 to position the block 15 in the circumferential direction with respect to the laminated plate 81.

[0044] The transfer unit 85 transfers the block 15 placed on the imaging table 71 described above onto the laminated plate 81, and includes a pair of clamping portions 86 that clamp the outer peripheral surface of the block 15 and a lifting mechanism (not shown in the figure) that raises and lowers the pair of clamping portions 86.

[0045] <Control device 90> As shown in FIGS. 4 to 6, an actuator of the movable table 32, an imaging unit 74 of the identification device 70, an inversion mechanism 75, and the transfer unit 85 are electrically connected to the control device 90.

[0046] The control device 90 controls the lifting and lowering of the movable table 32. When forming the block 15, the control device 90 first drives the actuator of the second hole punching die 50 to displace the second hole punching punch 53 to the punching position. In this state, the movable table 32 is lowered to form the first through hole 26. At this time, the actuator of the third hole punching die 55 is driven to displace the third hole punching punch 58 to the punching position. In this state, the movable table 32 is lowered to form the second through hole 27. Subsequently, until the number of times of lifting and lowering of the movable table 32 reaches a predetermined number of times, that is, the number of first iron core pieces 21 constituting the block 15, the second hole punching punch 53 and the third hole punching punch 58 are displaced to the retracted position. In this state, the movable table 32 is lowered so that the first through hole 26 and the second through hole 27 are not formed in the first iron core piece 21.

[0047] The control device 90 controls the driving of the inversion mechanism 75 to lift the block 15 placed on the imaging table 71 and invert the block 15 up and down. The control device 90 images the upper end surface 15a of the block 15 by the imaging unit 74 and detects the identification portion 29 of the block 15 based on the captured image.

[0048] Here, the identification part 29 for identifying one of the two-column progressive press devices 30 is the second through hole 27 formed in the second core piece 25, and the identification part 29 for identifying the other is a shape in which the second through hole 27 is not formed at a position corresponding to the second through hole 27 in the second core piece 25.

[0049] The control device 90 forms the laminate 16 by controlling the drive of the transfer part 85 so as to stack only the block 15 formed by the column of the progressive press device 30 corresponding to the detected identification part 29.

[0050] <Method for manufacturing the stator core 10> As shown in FIGS. 4 to 6, the method for manufacturing the stator core 10 includes a block forming step, a detection step, and a laminate forming step.

[0051] (Block forming step) As shown in FIG. 4, in the block forming step, the core pieces 20 are punched out from the thin plate-shaped workpiece W by the plurality of progressive press devices 30, and the plurality of punched core pieces 20 are stacked for each progressive press device 30 to form the block 15. At this time, the second through hole 27 for identifying the progressive press device 30 that formed the block 15 is formed only in the second core piece 25 that constitutes one end surface (the lower end surface in this embodiment) of the block 15.

[0052] As described above, after the block 15 formed in the block forming step is conveyed downstream by the conveying device 36, it is placed on the imaging table 71 by a robot arm (not shown).

[0053] (Detection step) As shown in FIG. 5, in the detection step, as described above, the block 15 is inverted up and down by the inversion mechanism 75 so that the second core piece 25 faces upward.

[0054] The upper end surface 15a of the block 15 is imaged by the imaging unit 74. Thereby, the identification part 29 is detected. At this time, the phase of the block 15 is detected based on the image of the upper end surface 15a of the block 15, and the mounting portion 73 is rotated so that the phase of the block 15 becomes the reference phase.

[0055] As described above, the block 15 set as the reference phase in the detection step is transferred onto the stacking plate 81 by the transfer unit 85. (Stacking body forming step) As shown in FIG. 6, in the stacking body forming step, the stacking body 16 is formed by stacking only the blocks 15 formed by the in-line press device 30 corresponding to the identification portion 29 detected in the detection step onto the stacking plate 81.

[0056] <Operation of the first embodiment> As shown in FIGS. 4 to 6, it is possible to prevent a plurality of blocks 15 formed by different in-line press devices 30 among the plurality of in-line press devices 30 from being mixed in one stacking body 16. Further, since it is only necessary to form the identification portion 29 for identifying the in-line press device 30 that formed the block 15 only on the upper end surface of the second core piece 25 that constitutes the upper end surface 15a of the block 15, the number of core pieces 20 forming the identification portion 29 is minimized. As a result, the locations where the block 15 needs to be modified due to the formation of the identification portion 29 can be minimized.

[0057] <Effect of the first embodiment> (1-1) In the block forming step, the identification portion 29 for identifying the in-line press device 30 that formed the block 15 is formed only on the upper end surface of the second core piece 25 that constitutes the upper end surface 15a of the block 15. In the detection step, prior to the stacking body forming step, the imaging unit 74 detects the identification portion 29. In the stacking body forming step, the stacking body 16 is formed by stacking only the blocks 15 formed by the in-line press device 30 corresponding to the detected identification portion 29.

[0058] According to such a method, since the above-described operation is achieved, it is possible to easily reduce the dimensional accuracy of the stator core 10 and thus the variation in the performance of the motor. (1-2) The plurality of progressive press devices 30 are arranged in parallel and simultaneously punch out the core pieces 20 from a common workpiece W respectively.

[0059] According to such a method, since a plurality of blocks 15 are simultaneously formed from a common workpiece W by the plurality of rows of progressive press devices 30 arranged in parallel, the blocks 15 can be efficiently formed.

[0060] (1-3) Two progressive press devices 30 are arranged in parallel. The identification part 29 for identifying one of the progressive press devices 30 is the second through hole 27 formed in the second core piece 25 by one of them. The identification part 29 for identifying the other of the progressive press devices 30 has a shape in which the second through hole 27 is not formed at a position corresponding to the second through hole 27 in the second core piece 25.

[0061] According to such a method, by detecting the presence or absence of the second through hole 27 formed in the second core piece 25 as the identification part 29, one and the other of the two rows of progressive press devices 30 can be identified.

[0062] (1-4) The plurality of second through holes 27 are formed at rotationally symmetric positions centered on the axis of the stator core 10, that is, the axis of the block 15. There is a possibility that the magnetic flux distribution generated in the stator core 10 may be disturbed by forming the second through hole 27 in the second core piece 25 as the identification part 29.

[0063] In this regard, according to the above method, since the plurality of second through holes 27 are formed at rotationally symmetric positions centered on the axis of the stator core 10, the disturbance of the magnetic flux distribution generated in the stator core 10 can be suppressed.

[0064] (1-5) In the detection step, the upper end surface of the second core piece 25 constituting the upper end surface 15a of the block 15 is imaged, and the identification part 29 is detected based on the captured image. According to such a method, the identification part 29 can be detected by a simple method of detecting the identification part 29 based on the image of the upper end surface 15a of the block 15.

[0065] <Second Embodiment> Next, with reference to FIG. 7, a second embodiment in which the manufacturing method of the motor core is embodied as the manufacturing method of the stator core will be described focusing on the differences from the first embodiment. In this embodiment, the identification part 29 is not provided on the second core piece 25 of the block 15, and the identification part 29 is provided on the core piece that constitutes the end surface of the block 15 on the side opposite to the second core piece 25, which is different from the first embodiment.

[0066] Hereinafter, for the configurations of the second embodiment that are the same as or corresponding to the configurations of the first embodiment, the same reference numerals as those in the first embodiment may be used to omit redundant explanations.

[0067] As shown in FIG. 7, a second through hole 27 is provided in the third core piece 221 that constitutes the upper end surface 15a, which is the end surface of the block 15 on the side opposite to the second core piece 25. The third core piece 221 basically has the same configuration as the first core piece 21.

[0068] In this embodiment, the identification part 29 for identifying one of the progressive press devices 30 is the second through hole 27 formed in the third core piece 221 by one. The identification part 29 for identifying the other of the progressive press devices 30 has a shape in which the second through hole 27 is not formed at a position corresponding to the second through hole 27 in the third core piece 221.

[0069] Also, in the block forming step, the second through hole 27 for identifying the progressive press device 30 that forms the block 15 is formed only in the third core piece 221. The third core piece 221 constitutes the upper end surface 15a of the block 15 that is pushed downward from inside the squeezing 62 of the progressive press device 30.

[0070] Also, in the detection step, the inversion mechanism 75 is omitted. <Operational Effects of the Second Embodiment> According to this embodiment, in addition to the operational effects (1-1) to (1-5) of the first embodiment, the following operational effects can be achieved.

[0071] (2-1) An identification portion 29 is provided on a third core piece 221 that constitutes an end face of the block 15 opposite to the second core piece 25. According to such a configuration, in the block forming process, the identification portion 29 is provided on the upper end face 15a of the block 15 that is pushed downward from the inside of the squeezing ring 62. As a result, it becomes unnecessary to invert the block 15 placed on the imaging table 71 after the block forming process, so the inversion mechanism 75 can be omitted in the detection process. Therefore, the manufacturing apparatus 100 of the stator core 10 can be simplified.

[0072] <Modification Example> This embodiment can be implemented with the following modifications. This embodiment and the following modification examples can be implemented in combination with each other within a technically non - conflicting range.

[0073] ·In the first embodiment, the upper end face 15a of the block 15 is imaged by the imaging unit 74, but the lower end face may be imaged instead. In this case, the process of inverting the block 15 by the inversion mechanism 75 can be omitted.

[0074] ·In each of the above embodiments, the shape of the second through - hole 27 is circular in plan view, but the shape of the second through - hole 27 may be semi - circular or rectangular in plan view. ·The number of the second through - holes 27 is not limited to three, and may be one, two, or four or more.

[0075] Incidentally, there is a trade-off in that as the number of the second through-holes 27 increases, the mass of the stator core 10 decreases, resulting in a decrease in motor torque. In this regard, when only one second through-hole 27 is provided in the core pieces 25, 221 provided with the identification portion 29, since the number of the second through-holes 27 is minimized, it is possible to minimize the decrease in motor torque caused by the decrease in the mass of the stator core 10.

[0076] ·In each of the above embodiments, the plurality of second through-holes 27 are formed at rotationally symmetric positions about the axis of the stator core 10. However, the plurality of second through-holes 27 do not have to be formed at rotationally symmetric positions about the axis of the stator core 10. That is, the intervals in the circumferential direction between the adjacent second through-holes 27 in the circumferential direction may be different from each other.

[0077] ·In each of the above embodiments, the configuration in which the two progressive press devices 30 are arranged in parallel is illustrated. However, a configuration in which three or more progressive press devices 30 are arranged in parallel may be employed. In this case, for example, for one row, the block 15 may be identified by using a shape in which the second through-hole 27 is not formed at the position corresponding to the second through-hole 27 among the core pieces 25, 221 provided with the identification portion 29. Further, for the other rows, the second through-hole 27 may be used as the identification portion 29 by making the shape of the second through-hole 27 different for each row.

[0078] ·In each of the above embodiments, the shape in which the second through-hole 27 is not formed at the position corresponding to the second through-hole 27 among the core pieces 25, 221 provided with the identification portion 29 and the second through-hole 27 are used as the identification portion 29. However, the shape of the identification portion 29 is not limited to this. For example, the identification portion 29 may be configured by a dowel shape, or the identification portion 29 may be configured by a notch provided on the outer peripheral surface of the core piece 25, 221.

[0079] ·In each of the above embodiments, the identification portion 29 is the shape in which the second through hole 27 is not formed at the position corresponding to the second through hole 27 in the core pieces 25 and 221 provided with the identification portion 29, but the present invention is not limited to this. The through holes as the identification portion 29 may be provided in all the blocks 15 formed by the progressive press device 30, respectively. At this time, by making at least one of the shape or the size of the through holes different for each column, the progressive press device 30 that forms the block 15 is identified. In this case, the progressive press device 30 that forms the block 15 can be identified by detecting the second through holes 27 in which at least one of the shape or the size is different.

[0080] ·In each of the above embodiments, an example is given in which a plurality of progressive press devices 30 are arranged in parallel and the core pieces 20 are simultaneously punched out from a common workpiece W, but the plurality of progressive press devices 30 may be independent of each other.

[0081] ·The present invention can also be embodied as a method for manufacturing a rotor core.

Explanation of Reference Numerals

[0082] 10…Stator core 10a…Central hole 11…Yoke 12…Teeth 13…Slot 15…Block 15a…Upper end face 16…Laminated body 20…Core piece 21…First core piece 22…Pin 25…Second core piece 26…First through hole 27…Second through hole 29‥Identification portion 30…Progressive press device 31…Fixed table 32…Movable table 33…Lower die set 34…Upper die set 35…Stripper plate 36…Conveyor mechanism 40…First punching die 41…First punching die 43…First punching punch 45…First press die 46…First press die 48…First press punch 50…Second punching die 51…Second punching die 53…Second punching punch 55…Third punching die 56…Third punching die 58…Third punching punch 60…Second press die 61…Second press die 62…Squeezing ring 63…Second press punch 70…Identification device 71…Imaging stage 72…Base 73…Placement part 74…Imaging part 75…Inversion mechanism 76…Clamping part 80…Laminated body forming device 81…Laminated plate 82…Plate body 83…Post part 85…Transfer part 86…Clamping part 90…Control device 100…Manufacturing device 221…Third iron core piece

Claims

1. A block forming step of punching out core pieces from a thin plate-shaped workpiece by a plurality of progressive press devices, respectively, and forming a block by laminating the plurality of punched-out core pieces for each of the progressive press devices; A laminate forming step of forming a laminate by laminating a plurality of the blocks, the method for manufacturing a motor core comprising: In the block forming step, an identification portion for identifying the progressive press device that formed the block is formed only on one end surface of the core piece that constitutes one end surface of the block; Prior to the laminate forming step, a detection step of detecting the identification portion by a detection device is provided; In the laminate forming step, the laminate is formed by laminating only the blocks formed by the progressive press device corresponding to the detected identification portion; A method for manufacturing a motor core.

2. The plurality of progressive press devices are arranged in parallel and simultaneously punch out the core pieces from a common workpiece, respectively. The method for manufacturing a motor core according to Claim 1.

3. Two of the progressive press devices are arranged in parallel; The identification portion for identifying one of the progressive press devices is a through hole formed in the core piece by the one; The identification portion for identifying the other of the progressive press devices has a shape in which the through hole is not formed at a position corresponding to the through hole in the core piece. The method for manufacturing a motor core according to Claim 2.

4. The plurality of through holes are formed at rotationally symmetric positions centered on the axis of the block. The method for manufacturing a motor core according to Claim 3.

5. Only one through hole is provided in the core piece. The method for manufacturing a motor core according to Claim 3.

6. The identification portion is a through hole formed in each of all the blocks formed by the plurality of progressive press devices; At least one of the shape or size of the identification portion is different for each of the progressive press devices that formed the block. The method for manufacturing a motor core according to Claim 2.

7. In the detection step, the one end surface is imaged, and the identification portion is detected based on the captured image. The method for manufacturing a motor core according to Claim 1.

Images