Manufacturing device for laminated iron core

Abstract

To apply an appropriate back pressure when forming an iron core member by punching a metal plate, and also suppress upward push of the iron core member placed on a placement base.SOLUTION: A manufacturing device 10 is provided with: a lower die 20; an upper die 40 having an outer shape punching punch 45 for forming an iron core member 5 by punching a metal plate W; a support member 32 for liftably supporting a placement base 30 on which the iron core member 5 is sequentially placed; a lifting motor 36 for lifting the placement base 30; and a control device 90 for controlling the lifting motor 36. The control device 90 is provided with a torque control unit 94 configured to set output torque of the lifting motor 36 to first output torque when not punching the metal plate W, and set the output torque of the lifting motor 36 to second output torque higher than the first output torque when punching the metal plate W to form the iron core member 5, such that a difference between the first output torque and the second output torque is variable.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an apparatus for manufacturing a laminated core. [Background technology]

[0002] Laminated cores used in motors and the like are formed by punching a strip-shaped metal plate (e.g., strip-shaped steel plate) into a predetermined shape to form core members (cores), and stacking and integrating the formed core members. For example, laminated cores are formed by stacking and integrating core members by caulking, welding, bonding, or the like. For example, Patent Document 1 discloses a manufacturing device for manufacturing a laminated core in which a plurality of core members are stacked and bonded together using an adhesive.

[0003] The manufacturing device of Patent Document 1 includes a receiving table on which the core members are sequentially placed, a lifting motor for raising and lowering the receiving table, and a control device for controlling the rotational operation of the lifting motor. In order to more effectively stack the laminated core, the torque limit value of the lifting motor is set to "high" when punching the core members, and an upward pressure (back pressure) is applied by the receiving table on which the laminated core members are sequentially stacked, and when the core members are not being punched, the torque limit value of the lifting motor is set to "low" to prevent the receiving table from pushing up the core members. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5859715 Summary of the Invention [Problem to be solved by the invention]

[0005] However, if the output torque of the lifting motor is not set appropriately, sufficient back pressure may not be applied, which may result in the core material not being punched or stacked properly, or the core material being pushed up by the support base.

[0006] The present invention has been made in consideration of these points, and its object is to provide a laminated core manufacturing apparatus that can apply an appropriate back pressure when punching a metal plate to form an iron core member, and can suppress the iron core member placed on a mounting table from being pushed up. [Means for solving the problem]

[0007] The laminated core manufacturing apparatus according to the present invention is a method for manufacturing a laminated core in which a plurality of core members are laminated and bonded to each other. join a control device for controlling the upper die and the lifting motor, wherein the control device sets an output torque of the lifting motor to a first output torque so as to suppress the pushing up of the core material by the mounting table when the metal plate is not punched out by the punch, and sets the output torque of the lifting motor to a second output torque higher than the first output torque so as to apply a back pressure to the core material by the mounting table when the metal plate is punched out by the punch to form the core material, and further comprises a torque control unit configured to be able to change a difference between the first output torque and the second output torque.

[0008] In the laminated core manufacturing device according to the present invention, the torque control unit is configured to be able to change the difference between the first output torque and the second output torque. According to the above aspect, the first output torque and the second output torque can be appropriately set according to the metal plate and the core member to be formed. Therefore, it is possible to apply an appropriate back pressure when punching the metal plate to form the core member while suppressing the occurrence of push-up of the core member placed on the mounting table.

[0009] Another laminated core manufacturing apparatus according to the present invention is a method for manufacturing a laminated core in which a plurality of core members are laminated and bonded to each other. join a control device for controlling the upper die and the lifting motor, wherein the control device sets an output torque of the lifting motor to a first output torque so as to suppress the pushing up of the core material by the mounting table when the metal plate is not punched out by the punch, and sets the output torque of the lifting motor to a second output torque higher than the first output torque so as to apply back pressure to the core material by the mounting table when the metal plate is punched out by the punch to form the core material, and further comprises a torque control unit configured to be able to change the first output torque.

[0010] In another laminated core manufacturing device according to the present invention, the torque control unit is configured to be able to change the first output torque. According to the above aspect, the first output torque can be appropriately set according to the metal plate and the core member to be formed. This makes it possible to more reliably prevent the core member placed on the mounting table from being pushed up. In addition, by appropriately setting the second output torque, it is possible to apply an appropriate back pressure when punching the metal plate to form the core member. Effect of the Invention

[0011] According to the present invention, it is possible to provide a laminated core manufacturing apparatus that can apply an appropriate back pressure when punching a metal plate to form an iron core member and can suppress the upward thrust of the iron core member placed on a mounting table. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a cross-sectional view showing a part of a manufacturing apparatus for a laminated core according to one embodiment. [Diagram 2] FIG. 2 is an example of a graph showing the relationship between the vertical position of the upper mold, the position of the mounting table, and the output torque of the lifting motor according to one embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of a laminated core manufacturing apparatus according to the present invention will be described with reference to the drawings. Note that the embodiment described here is not intended to limit the present invention in any particular way. Also, the same reference numerals are used for members and parts that perform the same function, and duplicated descriptions are omitted or simplified as appropriate.

[0014] As shown in FIG. 1, a laminated iron core manufacturing apparatus 10 (hereinafter referred to as manufacturing apparatus 10) of this embodiment manufactures a laminated iron core 8 in which a plurality of core members 5 are stacked and bonded to each other. The manufacturing apparatus 10 is a progressive press die. In the manufacturing apparatus 10, a strip-shaped metal plate W is intermittently conveyed in a progressive direction D. The strip-shaped metal plate W is, for example, a coil material (strip-shaped thin steel plate). The manufacturing apparatus 10 includes a lower die 20, an upper die 40, a stripper plate 60, and a control device 90.

[0015] The lower die 20 is fixed to a floor surface. As shown in Fig. 1, the lower die 20 is provided with an outline punching stage 25. The outline punching stage 25 includes a die plate 22, a die 23, an outline punching die hole 26, a squeeze ring 27, and an outline punching punch 45, which will be described later. The outline punching die hole 26 is an example of a die hole. The outline punching punch 45 is an example of a punch.

[0016] The lower mold 20 has a lower mold body 21, a die plate 22, and a die 23. The die plate 22 and the die 23 are placed on the lower mold body 21. The die plate 22 holds the die 23. The die 23 includes an outer shape punching stage 25. A die hole 26 for punching the outer shape is formed in the die 23. An upper surface 22T of the die plate 22 and an upper surface 23T of the die 23 are located at the same height.

[0017] As shown in Fig. 1, squeeze ring 27 is disposed below die 23. Squeeze ring 27 holds formed core member 5 from the side. Squeeze ring 27 applies lateral pressure (i.e., clamping force) to stacked core members 5. Squeeze ring 27 holds core member 5 punched into outline punching die hole 26 by outline punching punch 45 (described later) with a predetermined lateral pressure.

[0018] The strip-shaped metal sheet W is intermittently transported to the lower die 20 by a transport device (not shown) provided near the manufacturing device 10. The strip-shaped metal sheet W is intermittently transported to the outline punching stage 25. The transport device holds the strip-shaped metal sheet W in a wound state. The strip-shaped metal sheet W is transported to the lower die 20 by an unwinding device (not shown) of the transport device, and the end material of the pressed strip-shaped metal sheet W is transported from the lower die 20 by a winding device (not shown) of the transport device and wound up on the winding device. Note that instead of the unwinding device and winding device of the transport device, the strip-shaped metal sheet W may be sandwiched between a pair of upper and lower rotating rolls arranged on the upstream and downstream sides of the manufacturing device 10, respectively, and transported.

[0019] As shown in Fig. 1, the manufacturing apparatus 10 includes a mounting table 30, a support member 32, and a lifting motor 36. The mounting table 30 is provided so as to be capable of rising and lowering. The formed core members 5 are sequentially placed on the mounting table 30. The mounting table 30 has a mounting surface 30F on which the core members 5 are placed. The mounting surface 30F may be located inwardly of the die 23 and the squeeze ring 27. The laminated core 8 is manufactured on the mounting surface 30F.

[0020] As shown in FIG. 1, the support member 32 supports the mounting table 30 so that it can be raised and lowered. The support member 32 includes a support shaft 33 and a ball screw 35. The support shaft 33 extends in the vertical direction Z. The upper end of the support shaft 33 is connected to the lower end of the mounting table 30. The support shaft 33 supports the mounting table 30. The lower end of the support shaft 33 is connected to a nut 35A of the ball screw 35, which will be described later. The ball screw 35 includes a nut 35A and a screw shaft 35B. The nut 35A is screwed into the screw shaft 35B. The screw shaft 35B is connected to a rotating shaft of the lifting motor 36. The lifting motor 36 rotates to rotate the screw shaft 35B, thereby lifting and lowering the nut 35A. This also lifts and lowers the mounting table 30.

[0021] As shown in FIG. 1, the lifting motor 36 lifts and lowers the mounting table 30 via the support member 32. Examples of the lifting motor 36 include a servo motor and a stepping motor. The lifting motor 36 is controlled by a control device 90. The lifting motor 36 is configured to be able to press upward the core member 5 placed on the mounting surface 30F via the support member 32 and the mounting table 30. This applies a back pressure to the core member 5. As described later, the core member 5 placed on the mounting table 30 can be applied with a back pressure caused by setting the output torque of the lifting motor 36 to a first output torque and a back pressure caused by setting the output torque of the lifting motor 36 to a second output torque. Note that the back pressure applied to the core member 5 by setting the output torque to the first output torque is smaller than the lateral pressure applied to the core member 5 by the squeeze ring 27. This makes it possible to suppress the thrust of the core member 5.

[0022] As shown in Fig. 1, the manufacturing apparatus 10 includes a sensor 38 that detects a load applied from the outer shape punching punch 45 to the mounting table 30 when the metal plate W is punched to form the iron core member 5. The sensor 38 is provided on the mounting table 30. The sensor 38 is connected to a control device 90. The sensor 38 is, for example, a pressure sensor. Note that the sensor 38 directly detects the load applied from the outer shape punching punch 45 to the mounting table 30, but the sensor may indirectly detect the load by another method.

[0023] As shown in FIG. 1, the upper die 40 is disposed above the lower die 20. The upper die 40 is configured to be able to rise and fall (to be able to move in the vertical direction Z). The upper die 40 is configured to be able to approach and move away from the lower die 20. The upper die 40 has an outline punch 45 corresponding to the outline punching die hole 26. The upper die 40 and the outline punching punch 45 rise and fall together. The outline punching punch 45 is located above the outline punching die hole 26. The outline punching punch 45 is configured to be able to pass through the outline punching die hole 26. In the outline punching stage 25, after the upper die 40 descends and approaches the lower die 20, the strip-shaped metal plate W is punched out by the outline punching punch 45 and the outline punching die hole 26. As a result, the outer shape of the core member 5 is formed on the band-shaped metal plate W to complete the core member 5, and the core members 5 are sequentially stacked on the mounting table 30. When the band-shaped metal plate W is punched out, the output torque of the lifting motor 36 is changed to a second output torque as described below, and back pressure is applied to the core members 5. Here, the stacked core members 5 are joined to each other by crimping. For example, the laminated core 8 is formed by repeatedly joining the crimped portions (joint portions) formed on each of the two core members 5 stacked in the vertical direction Z to each other by crimping.

[0024] As shown in FIG. 1, the stripper plate 60 is provided on the upper die 40. The stripper plate 60 is disposed at a position facing the die plate 22 of the lower die 20. The stripper plate 60 is configured to be movable in the vertical direction Z together with the upper die 40. The stripper plate 60 is configured to be movable downward to a lowest position (not shown) which is the lowest position. When the stripper plate 60 is punched out of the strip-shaped metal plate W by the outline punching punch 45, the stripper plate 60 restricts the metal plate W from moving in the vertical direction Z at the lowest position. When the stripper plate 60 moves to the lowest position, the stripper plate 60 is configured to press the intermittently conveyed strip-shaped metal plate W against the lower die 20 (here, the die plate 22 and the die 23) and to sandwich the strip-shaped metal plate W together with the lower die 20 (here, the die plate 22 and the die 23). The stripper plate 60 presses the strip-shaped metal plate W against the upper surface 22T of the die plate 22 and the upper surface 23T of the die 23. A punch insertion hole 60A through which the outer shape punching punch 45 is inserted is formed in the stripper plate 60. When the upper die 40 is further lowered in a state in which the stripper plate 60 presses the band-shaped metal sheet W against the die plate 22, the outer shape punching punch 45 protrudes from the punch insertion hole 60A and is inserted into the outer shape punching die hole 26.

[0025] 2 is an example of a graph showing the relationship between the vertical Z position of the upper die 40, the vertical Z position of the mounting table 30, and the output torque of the lifting motor 36 in one cycle from when the upper die 40, which is located at the top dead center, passes through the bottom dead center and returns to the top dead center again. The relationship between the vertical Z position of the upper die 40, the vertical Z position of the mounting table 30, and the output torque of the lifting motor 36 is not limited to that shown in FIG. 2. The vertical axis of FIG. 2 shows the vertical Z position of the upper die 40 and the vertical Z position of the mounting table 30, and the horizontal axis of FIG. 2 shows the angle (crank angle) of the upper die 40. In FIG. 1, the vertical Z position of the upper die 40 is shown by a solid line, the output torque of the lifting motor 36 is shown by a dashed line, and the vertical Z position of the mounting table 30 is shown by a dashed line.

[0026] As shown in FIG. 2, at time T0 when the upper die 40 is located at the top dead center, the strip-shaped metal sheet W is being conveyed in the forward feed direction D (see FIG. 1). At this time, the output torque of the lifting motor 36 is set to a first output torque by a torque control unit 94 described later. When the upper die 40 moves downward and passes the midpoint between the top dead center and the bottom dead center at time T1 and reaches time T2, the conveyance of the strip-shaped metal sheet W is completed. That is, the conveyance of the strip-shaped metal sheet W is stopped from time T2 to time T9 described later. When the upper die 40 moves further downward and reaches time T3, the stripper plate 60 comes into contact with the metal sheet W. When the upper die 40 moves further downward and reaches time T4, the punch for punching the outline of the metal sheet W starts to be punched by the punch for punching the outline of the metal sheet W. That is, the lower surface 45B of the punch for punching the outline of the metal sheet W comes into contact with the upper surface WT (see FIG. 1) of the metal sheet W. In the example shown in FIG. 2, at timing T4, the output torque of the lifting motor 36 is changed from the first output torque to the second output torque by the torque control unit 94. When the upper die 40 moves further downward and reaches timing T5, the core member 5 formed by punching the metal plate W starts to fall downward. Then, at timing T6, the punched and dropped core member 5 abuts against the upper surface 5T of the core member 5 placed on the placement table 30. When the upper die 40 moves further downward and reaches timing T7, the formed core member 5 and the laminated core members 5 are crimped and joined to each other by the punch for punching the outer shape 45. Also, at timing T7, the upper die 40 is located at the bottom dead center. In the example shown in FIG. 2, at timing T7, the output torque of the lifting motor 36 is changed from the second output torque to the first output torque by the torque control unit 94. Here, the torque control unit 94 holds the output torque of the lifting motor 36 at the second output torque from timing T4 to timing T7, and holds the output torque of the lifting motor 36 at the first output torque from timing T7 through timing T0 to timing T4. Then, the upper die 40 starts to move upward. When the upper die 40 moves upward from the bottom dead center and reaches timing T8, the pressing of the metal sheet W by the stripper plate 60 is completed.When the upper die 40 moves further upward and reaches timing T9, the conveyance of the strip-shaped metal sheet W starts. That is, from timing T9 through timing T0 to timing T2, the strip-shaped metal sheet W is conveyed in the forward feed direction D. Then, the upper die 40 moves upward, passes the midpoint at timing T10, and reaches the top dead center at timing T0. In this manner, the upper die 40 repeatedly descends and ascends (i.e., the outer shape punching punch 45 repeatedly descends and ascends), thereby manufacturing a laminated laminated core 8 having a preset thickness. When the laminated core 8 is manufactured, the lifting motor 36 is driven to lower the mounting table 30, and then the laminated core 8 is discharged from the manufacturing device 10 to the outside by a pusher (not shown). When the upper die 40 is positioned at the top dead point, the lower surface 45B of the punch 45 for punching out the contour is positioned at the top dead point, when the upper die 40 is positioned at the midpoint, the lower surface 45B of the punch 45 for punching out the contour is positioned at the midpoint, and when the upper die 40 is positioned at the bottom dead point, the lower surface 45B of the punch 45 for punching out the contour is positioned at the bottom dead point.

[0027] As shown in FIG. 1, the control device 90 controls the upper mold 40 and the lifting motor 36. The control device 90 includes, for example, a central processing unit (CPU) that executes instructions of a control program, a ROM that stores the program executed by the CPU, a RAM used as a working area for expanding the program, and a storage device such as a memory that stores the program and various data. The control device 90 includes an upper mold control unit 92 and a torque control unit 94. The functions of each unit of the control device 90 are realized by a program. This program is downloaded, for example, via the Internet. The program may be read from a recording medium such as a CD or DVD. The functions of each unit of the control device 90 may be realized by a processor and / or a circuit.

[0028] The upper die control unit 92 controls the lifting and lowering movement (movement in the vertical direction Z) of the upper die 40. In this embodiment, the upper die control unit 92 controls the movement of the outline punching punch 45 and the stripper plate 60 in the vertical direction Z by moving the upper die 40 in the vertical direction Z. The upper die control unit 92 controls the approach of the upper die 40 to the lower die 20 and the separation of the upper die 40 from the lower die 20.

[0029] The torque control unit 94 controls the lifting motor 36. The torque control unit 94 controls the lifting motor 36 to move up and down (movement in the vertical direction Z) of the mounting table 30. The torque control unit 94 controls the output torque of the lifting motor 36. The torque control unit 94 is provided to be able to change the output torque of the lifting motor 36. The back pressure applied to the iron core member 5 is changed by changing the output torque. The torque control unit 94 sets the output torque of the lifting motor 36 to a first output torque so as to suppress the pushing up of the iron core member 5 by the mounting table 30 when the metal plate W is not punched out by the outer shape punching punch 45. The torque control unit 94 sets the output torque of the lifting motor 36 to a second output torque higher than the first output torque so as to apply a back pressure to the iron core member 5 by the mounting table 30 when the metal plate W is punched out by the outer shape punching punch 45 to form the iron core member 5. The first output torque and the second output torque are output torques of the lifting motor 36 during the punching process (when the metal plate W is punched to form the iron core member 5, for example, when the upper die 40 is moving up and down). In other words, the output torque of the lifting motor 36 when the laminated iron core 8 formed on the mounting table 30 is carried out to the outside of the manufacturing apparatus 10 or when the mounting table 30 is moved to the initial position is not included in the first output torque and the second output torque.

[0030] The torque control unit 94 may be configured to be able to change the first output torque. The torque control unit 94 may be configured to be able to hold the first output torque constant. That is, the torque control unit 94 may be configured to be unable to change the first output torque. The torque control unit 94 may be configured to be able to change the second output torque. For example, the amount of change in the second output torque is greater than the amount of change in the first output torque. The torque control unit 94 may be configured to be able to change the difference between the first output torque and the second output torque.

[0031] The torque control unit 94 may be configured to be able to change the first output torque in accordance with the load applied to the mounting table 30 from the outline punching punch 45 when punching the metal plate W to form the iron core member 5. The torque control unit 94 may be configured to lower the first output torque as the load applied to the mounting table 30 from the outline punching punch 45 when punching the metal plate W to form the iron core member 5 becomes smaller.

[0032] Torque control unit 94 may be configured to be able to change the first output torque depending on the thickness of iron core member 5. Torque control unit 94 may be configured to reduce the first output torque as the thickness of iron core member 5 becomes thinner.

[0033] Torque control unit 94 may be configured to be able to change the first output torque depending on the outer diameter of iron core member 5. Torque control unit 94 may be configured to reduce the first output torque as the outer diameter of iron core member 5 becomes smaller.

[0034] The torque control unit 94 may be configured to be able to change the first output torque according to the number of crimped portions when crimping one core member 5. Crimping one core member 5 means stacking and crimping a core member 5 formed by punching a metal plate W on top of an iron core member 5 already placed on the mounting table 30. The torque control unit 94 may be configured to lower the first output torque as the number of crimped portions decreases.

[0035] Torque control unit 94 may be configured to be able to change the first output torque in accordance with the lateral pressure applied to core member 5 by squeeze ring 27. Torque control unit 94 may be configured to reduce the first output torque as the lateral pressure becomes smaller.

[0036] Torque control unit 94 may be configured to be able to change the first output torque according to warping of iron core member 5 caused by lateral pressure applied to iron core member 5 by squeeze ring 27. Torque control unit 94 may be configured to reduce the first output torque as the warping of iron core member 5 becomes smaller.

[0037] The torque control unit 94 may be configured to be able to change the first output torque according to the shear resistance of the metal sheet W when the metal sheet W is punched by the outline punching punch 45. The torque control unit 94 may be configured to lower the first output torque as the shear resistance of the metal sheet W becomes smaller.

[0038] Torque control unit 94 may be configured to be able to change the first output torque in accordance with the weight per sheet of iron core member 5. Torque control unit 94 may be configured to reduce the first output torque as the weight per sheet of iron core member 5 becomes lighter.

[0039] The torque control unit 94 may be configured to be able to change the second output torque in accordance with the load applied to the mounting table 30 from the outline punching punch 45 when punching the metal plate W to form the iron core member 5. The torque control unit 94 may be configured to increase the second output torque as the load applied to the mounting table 30 from the outline punching punch 45 when punching the metal plate W to form the iron core member 5 increases.

[0040] The torque control unit 94 may be configured to change the second output torque based on the load detected by the sensor 38. The torque control unit 94 may be configured to change the second output torque based on the load detected by the punch 45 before the lower surface 45B of the punch 45 comes into contact with the upper surface WT of the metal plate W (for example, before timing T4 in FIG. 2). That is, the torque control unit 94 may be configured to change the second output torque of the iron core member 5 to be formed later based on the load when the iron core member 5 was previously formed before the metal plate W is punched out to form the iron core member 5. The torque control unit 94 may be configured to change the second output torque based on the load detected by the sensor 38 while the metal plate W is being punched out by the punch 45 (for example, timing T4 to timing T5 in FIG. 2). That is, the torque control unit 94 may be configured to change the second output torque of the iron core member 5 to be formed later based on the load when the iron core member 5 was previously formed while the metal plate W is being punched out.

[0041] Torque control unit 94 may be configured to be able to change the second output torque depending on the thickness of iron core member 5. Torque control unit 94 may be configured to increase the second output torque as the thickness of iron core member 5 increases.

[0042] Torque control unit 94 may be configured to be able to change the second output torque depending on the outer diameter of iron core member 5. Torque control unit 94 may be configured to increase the second output torque as the outer diameter of iron core member 5 increases.

[0043] Torque control unit 94 may be configured to be able to change the second output torque according to the number of crimped portions when crimping one iron core member 5. Torque control unit 94 may be configured to increase the second output torque as the number of crimped portions increases.

[0044] Torque control unit 94 may be configured to be able to change the second output torque in accordance with the lateral pressure applied to iron core member 5 by squeeze ring 27. Torque control unit 94 may be configured to increase the second output torque as the lateral pressure increases.

[0045] Torque control unit 94 may be configured to be able to change the second output torque according to warping of iron core member 5 caused by lateral pressure applied to iron core member 5 by squeeze ring 27. Torque control unit 94 may be configured to increase the second output torque as the warping of iron core member 5 increases.

[0046] The torque control unit 94 may be configured to be able to change the second output torque according to the shear resistance of the metal sheet W when the metal sheet W is punched by the outline punching punch 45. The torque control unit 94 may be configured to increase the second output torque as the shear resistance of the metal sheet W increases.

[0047] The torque control unit 94 changes the output torque of the lift motor 36 from the first output torque to the second output torque. The torque control unit 94 holds the output torque of the lift motor 36 at the second output torque for a predetermined time. In the example shown in Fig. 2, the torque control unit 94 holds the output torque of the lift motor 36 at the second output torque from timing T4 to timing T7.

[0048] The torque control unit 94 may change the output torque of the lifting motor 36 from the first output torque to the second output torque during the period from when the lower surface 45B (see FIG. 1) of the punch for punching an outline of the outer shape passes through the midpoint between the top dead point and the bottom dead point to when it reaches the bottom dead point (for example, from timing T1 to timing T7 in FIG. 2). The torque control unit 94 may change the output torque of the lifting motor 36 from the first output torque to the second output torque during the period from when the lower surface 45B of the punch for punching an outline of the outer shape passes through the midpoint to when it comes into contact with the upper surface WB of the metal sheet W (for example, from timing T1 to timing T4 in FIG. 2). The torque control unit 94 may change the output torque of the lifting motor 36 from the first output torque to the second output torque when the lower surface 45B of the punch for punching an outline of the outer shape comes into contact with the upper surface WB of the metal sheet W (for example, from timing T4 in FIG. 2). The torque control unit 94 may change the output torque of the lifting motor 36 from the first output torque to the second output torque during the period from when the stripper plate 60 comes into contact with the upper surface WT of the metal plate W to when the lower surface 45B of the punch 45 reaches the bottom dead center (for example, from timing T3 to timing T7 in FIG. 2). The torque control unit 94 may change the output torque of the lifting motor 36 from the first output torque to the second output torque during the period from when the lower surface 45B of the punch 45 comes into contact with the upper surface WT of the metal plate W to when the core member 5 formed by punching out the metal plate W abuts against the upper surface 5T of the core member 5 placed on the placement table 30 (for example, from timing T3 to timing T6 in FIG. 2). The torque control unit 94 may change the output torque of the lifting motor 36 from the first output torque to the second output torque during the period from when the iron core member 5 formed by punching out the metal plate W starts to fall downward until the lower surface 45B of the punch 45 reaches the bottom dead center (for example, from timing T5 to timing T7 in FIG. 2). The torque control unit 94 may change the output torque of the lifting motor 36 from the first output torque to the second output torque during the period from when the iron core member 5 formed by punching out the metal plate W starts to fall downward until the formed iron core member 5 comes into contact with the upper surface 5T of the iron core member 5 placed on the placement table 30 (for example, from timing T5 to timing T6 in FIG. 2).The torque control unit 94 may change the output torque of the lift motor 36 from the first output torque to the second output torque during the period from when the core member 5 formed by punching the metal plate W abuts against the upper surface 5T of the core member 5 placed on the placement table 30 until the lower surface 45B of the punch 45 reaches the bottom dead center (for example, from timing T6 to timing T7 in FIG. 2). When changing the output torque of the lift motor 36, a signal for changing the output torque is transmitted from the control device 90 to the lift motor 36. Here, "changing the output torque of the lift motor 36" includes a case where a signal for changing the output torque is transmitted from the control device 90 to the lift motor 36 before the timing of changing the output torque of the lift motor 36, and the change in the output torque is completed at the timing of changing the output torque of the lift motor 36, and a case where a signal for changing the output torque is transmitted from the control device 90 to the lift motor 36 before the timing of changing the output torque of the lift motor 36, and the change in the output torque continues at the timing of changing the output torque of the lift motor 36.

[0049] The timing at which the torque control unit 94 changes the output torque of the lifting motor 36 from the first output torque to the second output torque may be the same in an n-th punching process in which the metal plate W is punched by the outline punch 45 to form the n-th (n is a natural number) iron core member 5, and in an (n+1)-th punching process in which the metal plate W is punched by the outline punch 45 to form the (n+1)th iron core member 5. For example, the timing at which the output torque is changed may be the same in the first punching process and the second punching process.

[0050] The torque control unit 94 may be configured to be able to change the timing at which the output torque of the lift motor 36 is changed from the first output torque to the second output torque. The torque control unit 94 may be configured to make the timing at which the output torque of the lift motor 36 is changed from the first output torque to the second output torque earlier as the second output torque is higher. The torque control unit 94 may be configured to make the timing at which the output torque of the lift motor 36 is changed from the first output torque to the second output torque earlier as the difference between the first output torque and the second output torque is larger. The torque control unit 94 may be configured to make the timing at which the output torque of the lift motor 36 is changed from the first output torque to the second output torque earlier as the thickness of the metal plate W is greater.

[0051] The torque control unit 94 changes the output torque of the lift motor 36 from the first output torque to the second output torque in a rectangular wave shape (see FIG. 2). The torque control unit 94 may gradually change the output torque of the lift motor 36 from the first output torque to the second output torque. The torque control unit 94 may change the output torque of the lift motor 36 from the first output torque to the second output torque in a trapezoidal wave shape, a sine wave shape, a triangular wave shape, or a sawtooth wave shape.

[0052] The torque control unit 94 changes the output torque of the lift motor 36 from the second output torque to the first output torque. The torque control unit 94 holds the output torque of the lift motor 36 at the first output torque for a predetermined time. In the example shown in Fig. 2, the torque control unit 94 holds the output torque of the lift motor 36 at the first output torque from time T7 through time T0 to time T4.

[0053] The torque control unit 94 may change the output torque of the lifting motor 36 from the second output torque to the first output torque during the period from the bottom dead point until the bottom surface 45B (see FIG. 1) of the outer shape punching punch 45 reaches the midpoint (for example, timing T7 to timing T10 in FIG. 2). The torque control unit 94 may change the output torque of the lifting motor 36 from the second output torque to the first output torque when the bottom surface 45B (see FIG. 1) of the outer shape punching punch 45 starts to rise from the bottom dead point (for example, timing T7 in FIG. 2).

[0054] The timing at which the torque control unit 94 changes the output torque of the lifting motor 36 from the second output torque to the first output torque may be the same in an n-th punching process in which the metal plate W is punched by the outline punch 45 to form the n-th (n is a natural number) iron core member 5, and in an (n+1)-th punching process in which the metal plate W is punched by the outline punch 45 to form the (n+1)th iron core member 5. For example, the timing at which the output torque is changed may be the same in the first punching process and the second punching process.

[0055] The torque control unit 94 may be configured to be able to change the timing at which the output torque of the lift motor 36 is changed from the second output torque to the first output torque. The torque control unit 94 may be configured to delay the timing at which the change of the output torque of the lift motor 36 from the second output torque to the first output torque is completed as the first output torque is lower. The torque control unit 94 may be configured to delay the timing at which the change of the output torque of the lift motor 36 from the second output torque to the first output torque is completed as the difference between the first output torque and the second output torque is larger.

[0056] The torque control unit 94 changes the output torque of the lift motor 36 from the second output torque to the first output torque in a rectangular wave shape (see FIG. 2). The torque control unit 94 may gradually change the output torque of the lift motor 36 from the second output torque to the first output torque. The torque control unit 94 may change the output torque of the lift motor 36 from the second output torque to the first output torque in a trapezoidal wave shape, a sine wave shape, a triangular wave shape, or a sawtooth wave shape.

[0057] As described above, in the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 is configured to be able to change the difference between the first output torque and the second output torque. According to the above aspect, the first output torque and the second output torque can be appropriately set according to the metal plate W and the core member 5 to be formed. Therefore, it is possible to apply an appropriate back pressure when punching out the metal plate W to form the core member 5, while suppressing the occurrence of push-up of the core member 5 placed on the mounting table 30.

[0058] In the laminated core manufacturing apparatus 10 of the present embodiment, the change amount of the second output torque may be larger than the change amount of the first output torque. According to the above aspect, the second output torque can be appropriately set according to the metal plate W and the core member 5 to be formed.

[0059] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to be able to change the second output torque and to keep the first output torque constant. According to the above aspect, the second output torque can be appropriately set in accordance with the metal plate W and the core member 5 to be formed.

[0060] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may be configured to be able to change the second output torque in accordance with the load applied to the mounting table 30 from the outline punching punch 45 when punching the metal plate W to form the core member 5. According to the above aspect, the second output torque can be appropriately set, so that an appropriate back pressure can be applied when punching the metal plate W to form the core member 5.

[0061] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may be configured to increase the second output torque as the load applied to the mounting table 30 from the outline punching punch 45 when punching the metal plate W to form the core member 5 increases. According to the above aspect, an appropriate back pressure can be applied when punching the metal plate W to form the core member 5.

[0062] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to change the second output torque based on the load detected by the sensor 38. According to the above aspect, the second output torque can be set more accurately.

[0063] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to change the second output torque based on the load detected by the sensor 38 before the lower surface 45B of the outline punching punch 45 comes into contact with the upper surface WT of the metal plate W. According to the above aspect, an appropriate back pressure can be applied when the metal plate W is punched to form the iron core member 5.

[0064] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to change the second output torque based on the load detected by the sensor 38 while the metal plate W is being punched out by the outline punch 45. According to the above aspect, an appropriate back pressure can be applied when the metal plate W is punched out to form the iron core member 5.

[0065] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may be configured to change the output torque of the lifting motor 36 from the first output torque to the second output torque during the period from when the lower surface 45B of the punch 45 for punching the outline passes the midpoint between the top dead point and the bottom dead point to when it reaches the bottom dead point. According to the above aspect, the torque control unit 94 changes the output torque to the second output torque during the short period from when the lower surface 45B of the punch 45 for punching the outline passes the midpoint to when it reaches the bottom dead point, so that it is possible to apply an appropriate back pressure when punching the metal plate W to form the core member 5 while suppressing the occurrence of thrust-up of the core member 5 placed on the mounting table 30.

[0066] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may change the output torque of the lifting motor 36 from the first output torque to the second output torque during the period from when the lower surface 45B of the outline punching punch 45 passes the midpoint until it comes into contact with the upper surface WT of the metal plate W. According to the above aspect, it is possible to apply back pressure at a more appropriate timing when punching the metal plate W to form the iron core member 5.

[0067] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may change the output torque of the lifting motor 36 from the first output torque to the second output torque when the lower surface 45B of the outline punching punch 45 comes into contact with the upper surface WT of the metal plate W. According to the above aspect, it is possible to apply back pressure at a more appropriate timing when punching the metal plate W to form the iron core member 5.

[0068] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to be able to change the second output torque in accordance with the thickness of the core member 5. According to the above aspect, the second output torque can be set more accurately.

[0069] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to increase the second output torque as the thickness of the core member 5 increases. According to the above aspect, a more appropriate back pressure can be applied when punching the metal plate W to form the core member.

[0070] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to be able to change the second output torque in accordance with the outer diameter of the core member 5. According to the above aspect, the second output torque can be set more accurately.

[0071] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to increase the second output torque as the outer diameter of the core member 5 increases. According to the above aspect, a more appropriate back pressure can be applied when the metal plate W is punched to form the core member 5.

[0072] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may be configured to be able to change the second output torque according to the number of crimped portions when crimping one core member 5. According to the above aspect, the second output torque can be set more accurately. Also, the core members 5 can be appropriately joined together by crimping.

[0073] The laminated core manufacturing apparatus 10 of this embodiment may be configured to increase the second output torque as the number of crimped portions increases. According to the above aspect, a more appropriate back pressure can be applied when punching the metal sheet W to form the core members 5. In addition, the core members 5 can be more reliably joined together by crimping.

[0074] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may be configured to be able to change the second output torque depending on the number of bonding locations when bonding one core member 5. According to the above aspect, the second output torque can be set more accurately. Also, the core members 5 can be appropriately bonded to each other by bonding.

[0075] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may be configured to increase the second output torque as the number of bonding points increases. According to the above aspect, a more appropriate back pressure can be applied when punching the metal sheet W to form the core members 5. In addition, the core members 5 can be more reliably joined together by bonding.

[0076] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to be able to change the second output torque in response to the lateral pressure applied to the core member 5 by the squeeze ring 27. According to the above aspect, the second output torque can be set more accurately.

[0077] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to increase the second output torque as the lateral pressure increases. According to the above aspect, a more appropriate back pressure can be applied when punching the metal sheet W to form the core member 5.

[0078] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to be able to change the second output torque in response to warping of the core member 5 caused by the lateral pressure applied to the core member 5 by the squeeze ring 27. According to the above aspect, the second output torque can be set more accurately.

[0079] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to increase the second output torque as the warpage of the core member 5 increases. According to the above-described aspect, a more appropriate back pressure can be applied when the metal plate W is punched to form the core member 5.

[0080] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to be able to change the second output torque depending on the shear resistance of the metal sheet W when the metal sheet W is punched out by the outline punching punch 45. According to the above aspect, the second output torque can be set more accurately.

[0081] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to increase the second output torque as the shear resistance of the metal sheet W increases. According to the above aspect, a more appropriate back pressure can be applied when the metal sheet W is punched out to form the iron core member 5.

[0082] Moreover, in the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 is configured to be able to change the first output torque. According to the above aspect, the first output torque can be appropriately set according to the metal plate W and the core member 5 to be formed. This makes it possible to more reliably prevent the core member 5 placed on the mounting table 30 from being pushed up. Furthermore, by appropriately setting the second output torque, it is possible to apply an appropriate back pressure when the metal plate W is punched to form the core member 5.

[0083] The laminated core manufacturing apparatus 10 of this embodiment may be configured to be able to change the first output torque in accordance with the load applied to the mounting table 30 from the outline punching punch 45 when punching the metal plate W to form the core member 5. According to the above aspect, the first output torque can be appropriately set, so that the occurrence of push-up of the core member 5 placed on the mounting table 30 can be more reliably suppressed.

[0084] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may be configured to reduce the first output torque as the load applied to the mounting table 30 from the outline punching punch 45 when punching the metal plate W to form the core member 5 becomes smaller. According to the above aspect, it is possible to appropriately suppress the occurrence of push-up of the core member 5 mounted on the mounting table 30.

[0085] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may be configured to change the output torque of the lifting motor 36 from the second output torque to the first output torque while the lower surface 45B of the outline punching punch 45 moves from the bottom dead point to the midpoint between the bottom dead point and the top dead point. According to the above aspect, the torque control unit 94 changes the output torque to the first output torque in the short time it takes for the lower surface 45B of the outline punching punch 45 to move from the bottom dead point to the midpoint, so that it is possible to apply an appropriate back pressure when punching the metal sheet W to form the iron core member 5, while suppressing the occurrence of thrusting of the iron core member 5 placed on the placement table 30.

[0086] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may change the output torque of the lifting motor 36 from the second output torque to the first output torque when the lower surface 45B of the outline punching punch 45 starts to rise from the bottom dead center. According to the above embodiment, the occurrence of push-up of the core member 5 placed on the mounting table 30 can be more reliably suppressed.

[0087] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to be able to change the first output torque in accordance with the thickness of the core member 5. According to the above aspect, the first output torque can be set more accurately.

[0088] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to reduce the first output torque as the thickness of the core member 5 becomes thinner. According to the above-described aspect, an appropriate back pressure can be applied to the core member 5 placed on the mounting table 30, thereby suppressing the occurrence of thrust-up of the core member 5.

[0089] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to be able to change the first output torque in accordance with the outer diameter of the core member 5. According to the above aspect, the first output torque can be set more accurately.

[0090] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to reduce the first output torque as the outer diameter of the core member 5 decreases. According to the above aspect, an appropriate back pressure can be applied to the core member 5 placed on the mounting table 30, thereby suppressing the occurrence of thrust-up of the core member 5.

[0091] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may be configured to be able to change the first output torque according to the number of crimped portions when crimping one core member 5. According to the above aspect, the first output torque can be set more accurately. Also, the core members 5 can be appropriately joined together by crimping.

[0092] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may be configured to lower the first output torque as the number of crimped portions decreases. According to the above aspect, it is possible to apply a more appropriate back pressure to the core members 5 placed on the mounting table 30. In addition, the core members 5 can be more reliably joined together by crimping.

[0093] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may be configured to be able to change the first output torque depending on the number of bonding locations when bonding one core member 5. According to the above aspect, the first output torque can be set more accurately. Also, the core members 5 can be appropriately bonded to each other by bonding.

[0094] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may be configured to lower the first output torque as the number of bonding points decreases. According to the above aspect, it is possible to apply a more appropriate back pressure to the core members 5 placed on the mounting table 30. In addition, it is possible to more reliably bond the core members 5 to each other by bonding.

[0095] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to be able to change the first output torque in response to the lateral pressure applied to the core member 5 by the squeeze ring 27. According to the above aspect, the first output torque can be set more accurately.

[0096] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may be configured to reduce the first output torque as the lateral pressure becomes smaller. According to the above aspect, an appropriate back pressure can be applied to the core material 5 placed on the mounting table 30, thereby suppressing the occurrence of thrust-up of the core material 5.

[0097] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to be able to change the first output torque in response to warping of the core member 5 caused by the lateral pressure applied to the core member 5 by the squeeze ring 27. According to the above aspect, the first output torque can be set more accurately.

[0098] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may be configured to reduce the first output torque as the warpage of the core member 5 decreases. According to the above aspect, an appropriate back pressure can be applied to the core member 5 placed on the mounting table 30, thereby suppressing the occurrence of thrust-up of the core member 5.

[0099] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to be able to change the first output torque in accordance with the shear resistance of the metal sheet W when the metal sheet W is punched out by the outline punch 45. According to the above aspect, the first output torque can be set more accurately.

[0100] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to reduce the first output torque as the shear resistance of the metal plate W decreases. According to the above-described aspect, an appropriate back pressure can be applied to the core member 5 placed on the mounting table 30, thereby suppressing the occurrence of thrust-up of the core member 5.

[0101] In the laminated core manufacturing apparatus 10 of the present embodiment, the torque control unit 94 may be configured to be able to change the first output torque in accordance with the weight per sheet of the core member 5. According to the above aspect, the first output torque can be set more accurately.

[0102] In the laminated core manufacturing apparatus 10 of this embodiment, the torque control unit 94 may be configured to reduce the first output torque as the weight per core member 5 becomes lighter. According to the above aspect, an appropriate back pressure can be applied to the core member 5 placed on the mounting table 30, thereby suppressing the occurrence of thrust-up of the core member 5.

[0103] Although the preferred embodiments of the present invention have been described above, the above-described embodiments are merely examples, and the present invention can be embodied in various other forms.

[0104] In the above-described embodiment, the stacked core members 5 are joined to each other by crimping, but the method of joining them is not limited to crimping. The stacked core members 5 may be joined to each other by, for example, welding, adhesion, or the like. When the stacked core members 5 are joined to each other by adhesion, the torque control unit 94 may be configured to change the first output torque according to the number of bonding points when bonding one core member 5. Bonding one core member 5 means stacking and bonding an iron core member 5 formed by punching a metal plate W on an iron core member 5 already placed on the mounting table 30. The torque control unit 94 may be configured to lower the first output torque as the number of bonding points decreases. In addition, the torque control unit 94 may be configured to change the second output torque according to the number of bonding points when bonding one core member 5. The torque control unit 94 may be configured to increase the second output torque as the number of bonding points increases.

[0105] When the stacked core members 5 are bonded to each other by adhesion, the manufacturing apparatus 10 may include an adhesive applicator that applies adhesive to the underside WL (see FIG. 1) of the metal plate W. In this case, the control device 90 includes an application control unit that controls the adhesive applicator. The application control unit may control the adhesive applicator to apply adhesive to the underside WL of the metal plate W during at least a portion of the period during which the torque control unit 94 sets the output torque of the lifting motor 36 to the second output torque.

[0106] In the above-described embodiment, the lower die body 21, the die plate 22, and the die 23 of the lower die 20 are configured as separate bodies, but they may be configured as an integral body as appropriate. For example, the die plate 22 and the die 23 may be configured as an integral body, or the die plate 22, the die 23, and the lower die body 21 may be configured as an integral body.

[0107] In the above-described embodiment, the upper surface 23T of the die 23 and the upper surface 22T of the die plate 22 are located at the same height, but are not limited to this. For example, the upper surface 23T of the die 23 may be located lower than the upper surface 22T of the die plate 22. In this case, the stripper plate 60 presses the belt-shaped metal sheet W against the upper surface 22T of the die plate 22.

[0108] In the above-described embodiment, the manufacturing apparatus 10 was equipped with a punch 45 for punching the outer shape and a die hole 26 for punching the outer shape, but it may further be equipped with a punch for punching the inner shape and a die hole for punching the inner shape, a punch for forming a pilot hole and a die hole for forming a pilot hole, etc.

[0109] In a series of manufacturing steps from the start of punching the first core member 5 to the discharge of the laminated core 8 to the outside of the manufacturing apparatus 10, the first output torque or the second output torque may be changed as described in the claims. Also, in different manufacturing steps, the first output torque or the second output torque may be changed as described in the claims. [Explanation of symbols]

[0110] 5 Core material 8 Laminated core 10 Manufacturing equipment (laminated iron core manufacturing equipment) 20 Lower mold 23 Die 26 Die hole for punching the outer shape (Die hole) 27 Squeeze Ring 30 Placement table 32 Support member 36 Lift motor 38 Sensors 40 Upper mold 45 Outline punching punch (punch) 90 Control device 94 Torque control section

Claims

1. A manufacturing apparatus for a laminated core in which a plurality of core members are stacked and bonded to each other, comprising: A lower mold having a die with a die hole formed therein; an upper die having a punch corresponding to the die hole and punching out a strip-shaped metal plate to form the core member; a mounting table that is provided so as to be movable up and down and on which the formed core members are successively placed; A support member that supports the mounting table so that the mounting table can be raised and lowered; a lifting motor for lifting and lowering the stage via the support member; a control device for controlling the upper mold and the lifting motor, The control device includes: a torque control unit configured to set the output torque of the lifting motor to a first output torque so as to suppress the loading table from pushing up the iron core material when the metal plate is not punched out by the punch, and to set the output torque of the lifting motor to a second output torque higher than the first output torque so as to apply back pressure to the iron core material by the loading table when the metal plate is punched out by the punch to form the iron core material, and to be able to change the first output torque.

2. 2. The manufacturing apparatus according to claim 1, wherein the torque control unit is configured to be able to change the first output torque in response to a load applied to the mounting table from the punch when the metal plate is punched to form the iron core member.

3. 3. The manufacturing apparatus according to claim 2, wherein the torque control unit is configured to reduce the first output torque as a load applied to the mounting table from the punch when punching the metal plate to form the iron core member becomes smaller.

4. 2. The manufacturing apparatus according to claim 1, wherein the torque control unit is configured to change the output torque of the lifting motor from the second output torque to the first output torque during a time period until the lower surface of the punch moves from the bottom dead center to a midpoint between the bottom dead center and the top dead center.

5. 5. The manufacturing apparatus according to claim 4, wherein the torque control unit changes the output torque of the lifting motor from the second output torque to the first output torque when the lower surface of the punch starts to rise from the bottom dead center.

6. The manufacturing apparatus according to claim 1 , wherein the torque control unit is configured to be able to change the first output torque in accordance with a thickness of the iron core member.

7. The manufacturing apparatus according to claim 6 , wherein the torque control section is configured to reduce the first output torque as the thickness of the iron core member becomes thinner.

8. The manufacturing apparatus according to claim 1 , wherein the torque control unit is configured to be able to change the first output torque in accordance with an outer diameter of the iron core member.

9. The manufacturing apparatus according to claim 8 , wherein the torque control unit is configured to reduce the first output torque as the outer diameter of the iron core member becomes smaller.

10. In the laminated core, the laminated core members are joined to each other by crimping, The manufacturing apparatus according to claim 1 , wherein the torque control unit is configured to be able to change the first output torque in accordance with the number of crimped portions when one of the iron core members is crimped.

11. The manufacturing apparatus according to claim 10 , wherein the torque control unit is configured to reduce the first output torque as the number of the crimped portions decreases.

12. The laminated core is formed by bonding the laminated core members together, The manufacturing apparatus according to claim 1 , wherein the torque control unit is configured to be able to change the first output torque in accordance with the number of bonding points when bonding one of the iron core members.

13. The manufacturing apparatus according to claim 12 , wherein the torque control unit is configured to reduce the first output torque as the number of the bonding points decreases.

14. a squeeze ring is disposed below the die, holds the formed core member from a side, and applies a lateral pressure to the core member; The manufacturing apparatus according to claim 1 , wherein the torque control unit is configured to be able to change the first output torque in response to the lateral pressure applied to the iron core member by the squeeze ring.

15. The manufacturing apparatus according to claim 14 , wherein the torque control section is configured to reduce the first output torque as the lateral pressure decreases.

16. a squeeze ring is disposed below the die, holds the formed core member from a side, and applies a lateral pressure to the core member; 2. The manufacturing apparatus according to claim 1, wherein the torque control unit is configured to be able to change the first output torque in response to a warp of the core material caused by the lateral pressure applied to the core material by the squeeze ring.

17. The manufacturing apparatus according to claim 16 , wherein the torque control unit is configured to reduce the first output torque as the warp of the iron core member decreases.

18. The manufacturing apparatus according to claim 1 , wherein the torque control unit is configured to be able to change the first output torque in response to a shear resistance of the metal plate when the metal plate is punched out by the punch.

19. The manufacturing apparatus according to claim 18 , wherein the torque control unit is configured to reduce the first output torque as the shear resistance of the metal plate decreases.

20. The manufacturing apparatus according to claim 1 , wherein the torque control unit is configured to be able to change the first output torque in accordance with a weight per sheet of the iron core member.

21. The manufacturing apparatus according to claim 20 , wherein the torque control section is configured to reduce the first output torque as the weight per sheet of the core member becomes lighter.

22. The manufacturing apparatus according to claim 1 , wherein the torque control unit is configured to set one of the second output torques.

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