Method for manufacturing a thin strip

Abstract

To provide a ribbon piece manufacturing method which can suppress damage to a rotary die cutter.SOLUTION: A ribbon piece manufacturing method comprises a punching process in which a ribbon piece is punched from a ribbon material by the use of a rotary die cutter comprising a die roll and an anvil roll. The die roll includes a die roll body on an outer peripheral surface of which a cutting blade projects, and the anvil roll includes an anvil roll body on an outer peripheral surface of which a groove is provided into which the cutting blade can be fitted in a state with a gap. In the punching process, the cutting blade of the die roll body is fitted into the groove of the anvil roll body in the state with the gap and is pushed into the ribbon material to cut the ribbon material while pinching the ribbon material between a die roll side elastic body, which is located on both sides of a base end part of the cutting blade on the outer peripheral surface of the die roll body, and both sides of the groove on the outer peripheral surface of the anvil roll body when passing the ribbon material between the die roll and the anvil roll.SELECTED DRAWING: Figure 3B

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing thin strip pieces by punching thin strip pieces from a thin strip using a rotary die cutter.

Background Art

[0002] Conventionally, it has often been required to manufacture thin strip pieces of a predetermined shape from thin strip materials such as thin metal plates, thin metal strips, and metal foils composed of metal materials, etc. This is because many components mounted on various machines and electronic devices are often formed from such thin strip pieces having a predetermined shape. Specifically, for example, as described in Patent Document 1, a laminated core used for a motor core or the like is formed by laminating thin strip pieces processed from an amorphous alloy thin strip or the like. Furthermore, many of the electrodes provided in secondary batteries and fuel cells are formed from thin metal strip pieces.

[0003] As a processing method for manufacturing thin strip pieces of a predetermined shape from a thin strip material, conventionally, press punching has been applied, but in recent years, a processing method using a rotary die cutter has been applied from the viewpoint of improving productivity and the like.

[0004] As a processing method using a rotary die cutter, for example, Patent Document 2 describes a processing method using a rotary cutter for punching a very thin metal member (thin strip material) such as a thin metal plate or a metal foil into a predetermined shape by shearing. This rotary cutter includes a first rotating member, a second rotating member, and an elastic body. In this rotary cutter, the first rotating member has at least one of a convex portion and a concave portion on its surface. The second rotating member is rotatable in a direction opposite to that of the first rotating member and has at least one of a convex portion and a concave portion on its surface. The elastic body is attached to at least a part of the stepped portion of the edge formed by the convex portion or the concave portion of the first rotating member. Further, the elastic body is attached to at least a part of the stepped portion of the edge formed by the convex portion or the concave portion of the second rotating member. Then, the metal member is sheared between the edges of the first rotating member and the second rotating member.

[0005] Furthermore, as a processing method using a rotary die cutter, for example, Patent Document 3 describes a processing method using a die-cutting device including a rotary die and an anvil roll. In this device, the rotary die has a die-cutting roll and a cutting edge protruding radially outward of the die-cutting roll, and the cutting edge includes a pair of first blade portions protruding from the outer peripheral surface along the circumferential direction of the die-cutting roll and spaced apart in the axial direction of the die-cutting roll. Further, the rotary die has a sponge that sandwiches the first blade portion in the axial direction of the die-cutting roll, and the compression ratio of the sponge at the location where the separation distance between the die-cutting roll and the anvil roll is the shortest is set to 40% or more. In this die-cutting device, when passing an electrode intermediate through between the rotary die and the anvil roll, the cutting edge of the rotary die is made to enter a thin strip material such as the electrode intermediate, and the thin strip material is cut along the cutting planned line, thereby manufacturing a thin strip piece having a predetermined shape from the thin strip material.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0007] On the other hand, for example, thin strip materials such as amorphous alloy thin strips are not easy to cut because they have high hardness and low ductility. Therefore, when using a rotary die cutter such as the rotary cutter described in Patent Document 2 to punch out a thin strip material with high hardness and low ductility by shearing, the rotary die cutter is easily damaged because its wear progresses early.

[0008] Furthermore, even when punching out thin strip pieces from a thin strip by cutting the thin strip with a rotary cutter such as the die cutting device described in Patent Document 3, when the hardness of the thin strip is high and the ductility is low, the rotary cutter is likely to be damaged because a strong load is applied to the cutting edge.

[0009] The present invention has been made in view of such points, and an object thereof is to provide a method for manufacturing thin strip pieces by punching out thin strip pieces from a thin strip using a rotary cutter, which can suppress damage to the rotary cutter.

Means for Solving the Problems

[0010] In order to solve the above problems, a method for manufacturing thin strip pieces according to the present invention is a method for manufacturing thin strip pieces including a punching step of punching out thin strip pieces from a thin strip using a rotary cutter including a die roll and an anvil roll, wherein the die roll includes a die roll body having a cutting edge projecting from an outer peripheral surface and having a shape corresponding to a peripheral edge of the thin strip piece, the anvil roll includes an anvil roll body having a groove provided on an outer peripheral surface into which the cutting edge of the die roll body can be fitted with a gap, and in the punching step, when passing the thin strip between the die roll and the anvil roll by rotating the die roll and the anvil roll in opposite directions to each other, while sandwiching the thin strip between a die roll side elastic body disposed on both sides of a base end portion of the cutting edge on the outer peripheral surface of the die roll body and both sides of the groove on the outer peripheral surface of the anvil roll body, the cutting edge of the die roll body is fitted into the groove of the anvil roll body with a gap and pushed into the thin strip to cut the thin strip, thereby punching out the thin strip piece from the thin strip.

Effects of the Invention

[0011] According to the present invention, damage to the rotary cutter can be suppressed.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3A

Figure 3B

Figure 4

Figure 5

Figure 6

Figure 7A

Figure 7B

Figure 8

MODE FOR CARRYING OUT THE INVENTION

[0013] Hereinafter, a method for manufacturing a thin strip piece according to an embodiment will be described. First, an outline of the method for manufacturing a thin strip piece according to the embodiment will be described by exemplifying the methods for manufacturing a thin strip piece according to the first embodiment and the second embodiment.

[0014] (First Embodiment) FIG. 1 is a side view schematically showing a manufacturing facility for implementing a method for manufacturing a strip piece according to the first embodiment. FIG. 2 is a schematic plan view showing a strip piece punched from a strip material using the method for manufacturing a strip piece according to the first embodiment. FIGS. 3A and 3B are process cross-sectional views schematically showing a punching process of the method for manufacturing a strip piece according to the first embodiment. FIG. 4 is an enlarged view of the X portion shown in FIG. 3B and is a view for explaining the mechanism of cutting the strip material in the punching process.

[0015] As shown in FIG. 1, a manufacturing facility 100 for implementing a method for manufacturing a strip piece according to the first embodiment includes a material supply device 10, a rotary die cutter 30, and a material recovery device 40, which are arranged in order in the conveying direction D1. The manufacturing facility 100 further includes two material conveying devices 20, which are arranged on the upstream side and the downstream side of the rotary die cutter 30 in the conveying direction D1, respectively.

[0016] The material supply device 10 has a rotating shaft 11 rotatably provided in the arrow direction so as to supply the strip material M to the rotary die cutter 30, and the strip material M is wound around the rotating shaft 11. The strip material M is an amorphous alloy strip. The material conveying device 20 has a pair of conveying rolls 21 that rotate with the strip material M sandwiched therebetween. The pair of conveying rolls 21 are arranged such that their rotating shafts are parallel to each other, and rotate in opposite directions as shown by the arrows to sandwich and convey the strip material M therebetween. The material recovery device 40 has a rotating shaft 41 rotatably provided in the arrow direction so as to wind up and recover the strip material M' after punching.

[0017] In the manufacturing equipment 100, first, the thin strip material M supplied from the material supply device 10 is conveyed to the rotary die cutter 30 by the upstream material conveyance device 20. Next, by implementing the method for manufacturing the thin strip pieces according to the first embodiment with the rotary die cutter 30, the thin strip pieces P shown in FIG. 2 are punched and manufactured from the thin strip material M. The thin strip pieces P are those in which the thin strip pieces forming each layer of the laminated stator core are further divided in the circumferential direction, and have a comb-tooth-shaped peripheral edge Pe and a flat peripheral edge Pf on the side opposite to this peripheral edge Pe. Next, the punched thin strip material M' is conveyed to the material recovery device 40 by the downstream material conveyance device 20 and recovered by the material recovery device 40. Hereinafter, the rotary die cutter 30 and the method for manufacturing the thin strip pieces according to the first embodiment will be described in detail.

[0018] As shown in FIGS. 1, 3A, and 3B, the rotary die cutter 30 includes a die roll 32 and an anvil roll 34. The die roll 32 includes a die roll body 32A and a die roll elastic layer (die roll side elastic body) 32B. The die roll body 32A is a cylindrical mold and is rotatably provided with its central axis parallel to the rotation axis of the conveying roll 21 as the rotation axis A1. A cutting edge 32Ac projects from the outer peripheral surface 32As of the die roll body 32A. The cutting edge 32Ac has a shape corresponding to the periphery of the thin strip P. That is, the planar shape of the cutting edge of the cutting edge 32Ac when the outer peripheral surface 32As of the die roll body 32A is developed into a plane is the same as the periphery of the thin strip P. Also, the cross-sectional shape of the cutting edge 32Ac is triangular. The die roll elastic layer 32B is fixed and provided on both sides of the base end of the cutting edge 32Ac on the outer peripheral surface 32As of the die roll body 32A and extends to the adjacent region of the base end of the cutting edge 32Ac. The die roll 32 rotates in the direction of the arrow while pressing the thin strip material M by the die roll elastic layer 32B around the rotation axis A1 of the die roll body 32A. The anvil roll 34 includes an anvil roll body 34A and an anvil roll elastic layer 34B. The anvil roll body 34A is a cylindrical mold and is rotatably provided with its central axis parallel to the rotation axis A1 as the rotation axis A2. A groove 34Ag into which the cutting edge 32Ac of the die roll body 32A can be fitted with a gap S is provided on the outer peripheral surface 34As of the anvil roll body 34A. The anvil roll elastic layer 34B is fixed and provided on both sides of the groove 34Ag on the outer peripheral surface 34As of the anvil roll body 34A and extends to the adjacent regions on both sides of the groove 34Ag. The anvil roll 34 rotates in the direction of the arrow while supporting the thin strip material M by the anvil roll elastic layer 34B around the rotation axis A2 of the anvil roll body 34A.

[0019] In the rotary die cutter 30, as shown in FIGS. 3A, 3B, and 4, the width W1 of the base end portion of the cutting edge 32Ac of the die roll body 32A is equal to or less than the width W2 of the groove 34Ag of the anvil roll body 34A. The clearance W3 between the cutting edge of the cutting edge 32Ac and the edge of the groove 34Ag is set such that the width W2 of the groove 34Ag is increased to about 5 times the thickness of the thin strip material M (about 20 μm to 30 μm), for example, about 0.1 mm to 0.15 mm. The thickness t1 of the die roll elastic layer 32B is thicker than the height h of the cutting edge 32Ac. Since the die roll elastic layer 32B is made of a resin sponge sheet and the anvil roll elastic layer 34B is made of a non-foamed resin multi-layer sheet, the hardness (Shore A) of the anvil roll elastic layer 34B is 3 times or more the hardness (Shore A) of the die roll elastic layer 32B. The depth dp at which the cutting edge 32Ac is pushed into the groove 34Ag is set such that the height h of the cutting edge 32Ac and the clearance d between the roll bodies 32A and 34A are increased to about 5 times the thickness of the thin strip material M (about 0.1 mm to 0.15 mm), for example.

[0020] In the method for manufacturing a thin strip piece according to the first embodiment, the rotary die cutter 30 is used to repeatedly punch out the thin strip piece P from the thin strip material M (punching step). In the punching step, as shown in FIGS. 3A and 3B, while sandwiching the thin strip material M between the outer peripheral surface 32Bs of the die roll elastic layer 32B and the outer peripheral surface 34Bs of the anvil roll elastic layer 34B, the die roll 32 and the anvil roll 34 are rotated in opposite directions as indicated by the arrows. Thereby, the thin strip material M is passed between the die roll 32 and the anvil roll 34. At this time, while sandwiching the thin strip material M between the die roll elastic layer 32B and the anvil roll elastic layer 34B, the cutting edge 32Ac of the die roll body 32A is inserted into the groove 34Ag of the anvil roll body 34A with a gap S and pushed into the thin strip material M.

[0021] As a result, as shown in FIG. 4, in the adjacent regions on both sides of the groove 34Ag of the anvil roll body 34A, the sandwiched portion Ms of the thin strip material M sandwiched between the die roll elastic layer 32B and the anvil roll elastic layer 34B is restrained by the elastic forces of both the die roll elastic layer 32B and the anvil roll elastic layer 34B. At the same timing, by protruding the cutting edge 32Ac of the die roll body 32A from the outer peripheral surface 32Bs of the die roll elastic layer 32B, the pressing position Mp where the cutting edge 32Ac is pushed into the thin strip material M is pushed down by the cutting edge 32Ac of the die roll body 32A. In this way, by applying a tensile stress due to restraint together with a tensile stress due to bending to the pressing position Mp of the thin strip material M, the thin strip material M is cut at the pressing position Mp.

[0022] Then, by continuously rotating the die roll 32 and the anvil roll 34, such cutting of the thin strip material M occurs continuously, and by repeatedly punching out the thin strip pieces P from the thin strip material M, a plurality of thin strip pieces P are manufactured.

[0023] According to the method for manufacturing a thin strip piece according to the first embodiment, by applying a tensile stress due to bending and a tensile stress due to restraint to the pressing position Mp of the thin strip material M and cutting the thin strip material M at the pressing position Mp, the thin strip material M can be punched out. Therefore, it is possible to avoid a strong load being applied to the cutting edge 32Ac, and thus damage to the rotary die cutter 30 can be suppressed as compared with the case of punching out the thin strip material M by shearing.

[0024] Further, the width W1 of the base end portion of the cutting edge 32Ac of the die roll body 32A is equal to or less than the width W2 of the groove 34Ag of the anvil roll body 34A, and the die roll elastic layer 32B extends to the adjacent region of the base end portion of the cutting edge 32Ac. As a result, without delay with respect to the timing of pushing the cutting edge 32Ac of the die roll body 32A into the thin strip material M, the sandwiched portion Ms of the thin strip material M can be restrained by the elastic force of the die roll elastic layer 32B in the adjacent regions on both sides of the groove 34Ag of the anvil roll body 34A. Therefore, the inflow of the thin strip material M into the groove 34Ag can be avoided, and a tensile stress due to restraint can be applied to the pressing position Mp of the thin strip material M with a magnitude sufficient for cutting.

[0025] Further, since the cutting blade 32Ac of the die roll body 32A is fitted into the groove 34Ag of the anvil roll body 34A with a gap S and pushed into the thin strip material M, the thin strip material M can be cut. Therefore, the clearance W3 between the cutting edge of the cutting blade 32Ac and the edge of the groove 34Ag can be increased to about 5 times the thickness of the thin strip material M (about 0.1 mm to 0.15 mm). For this reason, compared with the case where it is necessary to set the clearance between the punch and the die of the upper die and the lower die of the mold to about 10% of the thickness of the thin strip material M (about several μm) in order to punch the thin strip material M by shearing using a pair of upper and lower molds, the alignment of the die roll 32 and the anvil roll 34 becomes easier.

[0026] Furthermore, the hardness (Shore A) of the anvil roll elastic layer 34B is 3 times or more the hardness (Shore A) of the die roll elastic layer 32B. For this reason, while the hard anvil roll elastic layer 34B supports the thin strip material M and the soft die roll elastic layer 32B presses the thin strip material M, deformation of the clamped portion Ms of the thin strip material M accompanying the depression of the pressing position Mp of the thin strip material M can be suppressed, and the clamped portion Ms of the thin strip material M can be firmly restrained. As a result, the thin strip material M can be surely cut at the pressing position Mp, and the thin strip piece P can be punched out from the thin strip material M with the accuracy of the planar shape of the cutting edge of the cutting blade 32Ac.

[0027] (Modification of the First Embodiment) FIG. 5 is a process cross-sectional view schematically showing a main part of the punching process of the method for manufacturing a thin strip piece according to a modification of the first embodiment.

[0028] As shown in FIG. 5, the rotary die cutter 30V according to the modified example differs from the rotary die cutter 30 according to the first embodiment only in that the anvil roll 34 includes an anvil roll main body 34A and does not include an anvil roll elastic layer 34B. In the method for manufacturing a thin strip piece according to the modified example, unlike the method for manufacturing a thin strip piece according to the first embodiment, in the punching process, the rotary die cutter 30V is used, and while sandwiching the thin strip material M between the outer peripheral surface 32Bs of the die roll elastic layer 32B and the outer peripheral surface 34As of the anvil roll main body 34A, the die roll 32 and the anvil roll 34 are rotated in opposite directions as shown by the arrows. Thereby, the thin strip material M is passed between the die roll 32 and the anvil roll 34. At this time, while sandwiching the thin strip material M between the die roll elastic layer 32B and the adjacent regions on both sides of the groove 34Ag of the outer peripheral surface 34As of the anvil roll main body 34A so that the adjacent regions on both sides of the groove 34Ag of the outer peripheral surface 34As of the anvil roll main body 34A are in direct contact with the thin strip material M, the cutting edge 32Ac of the die roll main body 32A is fitted into the groove 34Ag of the anvil roll main body 34A with a gap S and pushed into the thin strip material M. Thereby, in the adjacent regions on both sides of the groove 34Ag of the anvil roll main body 34A, the clamped portion Ms of the thin strip material M clamped between the die roll elastic layer 32B and the anvil roll main body 34A is restrained by the elastic force of the die roll elastic layer 32B. At the same timing, by protruding the cutting edge 32Ac of the die roll main body 32A from the outer peripheral surface 32Bs of the die roll elastic layer 32B, the pressing position Mp where the cutting edge 32Ac is pushed into the thin strip material M is pushed down by the cutting edge 32Ac of the die roll main body 32A. In this way, by applying a tensile stress due to restraint together with a tensile stress due to bending to the pressing position Mp of the thin strip material M, the thin strip material M is cut at the pressing position Mp. Thereby, the thin strip piece P is punched out.

[0029] According to the method for manufacturing a thin strip piece according to the modified example, the same effects as those of the method for manufacturing a thin strip piece according to the first embodiment can be obtained, except for the effects obtained depending on the hardness conditions of the anvil roll elastic layer 34B.

[0030] (Second Embodiment) FIG. 6 is a side view schematically showing manufacturing equipment for implementing a method for manufacturing a thin strip piece according to the second embodiment. FIGS. 7A and 7B are process cross-sectional views schematically showing a punching process of the method for manufacturing a thin strip piece according to the second embodiment.

[0031] As shown in FIG. 6, manufacturing equipment 200 for implementing a method for manufacturing a thin strip piece according to the second embodiment includes a material supply device 50, a material conveyance device 60, a rotary die cutter 70, a separation roll 80, a product conveyance device 90, and a suction device 98, which are arranged in order in the conveyance direction D1.

[0032] The material supply device 50 has a rotary shaft 51 rotatably provided in the direction of the arrow so as to be able to supply the laminated sheet L to the rotary die cutter 70, and the laminated sheet L is wound around the rotary shaft 51. The laminated sheet L has a thin strip material M and an elastic sheet (die roll side elastic body) E placed on the surface Ma on the die roll 72 side of the thin strip material M to be described later. The thin strip material M is an amorphous alloy thin strip. The material conveyance device 60 has a pair of conveyance rolls 61 that rotate with the laminated sheet L sandwiched therebetween. The pair of conveyance rolls 61 are arranged such that their rotary shafts are parallel to each other, and rotate in opposite directions as shown by the arrows to sandwich and convey the laminated sheet L therebetween. The separation roll 80 is arranged such that its rotary shaft is parallel to the rotary shafts of the conveyance rolls 61. The product conveyance device 90 has a belt 92 wound around a pair of pulleys 94, and a magnet (not shown) is provided inside the belt 92 along the conveyance surface 92a of the belt 92. The pair of pulleys 94 are arranged such that their rotary shafts are parallel to the rotary shaft of the separation roll 80, and the belt 92 is provided such that the conveyance surface 92a moves in the conveyance direction D1 as the pulleys 94 rotate. The suction device 98 is arranged above the conveyance surface 92a of the belt 92.

[0033] In the manufacturing equipment 200, first, the laminated sheet L supplied from the material supply device 50 is conveyed by the material conveyance device 60 to the rotary die cutter 70. Next, by implementing the method for manufacturing the strip pieces according to the second embodiment with the rotary die cutter 70, the strip pieces P shown in FIG. 2 are repeatedly punched out from the strip material M of the laminated sheet L, thereby manufacturing a plurality of strip pieces P. At this time, the strip pieces P are punched out from the strip material M such that the flat peripheral edge Pf faces the conveyance direction D1. Next, by the rotation of the separation roll 80, the plurality of punched strip pieces P are conveyed in the conveyance direction D1 at intervals in the conveyance direction D1 with their flat peripheral edges Pf facing the conveyance direction D1, and their flat peripheral edges Pf are sequentially placed on the conveyance surface 92a of the belt 92 of the product conveyance device 90 and adsorbed by the magnetic force of the magnet. At the same time, by the rotation of the separation roll 80, the laminated sheet L' after punching is conveyed in the direction D2 and separated from the strip pieces P. Next, by the rotation of the pulley 94 of the product conveyance device 90, the conveyance surface 92a of the belt 92 is moved, and while the plurality of strip pieces P placed on the conveyance surface 92a are conveyed in the conveyance direction D1, the suction device 98 sucks and removes the sheet pieces Ep punched out from the elastic body sheet E when the strip pieces P are punched out from each of the strip pieces P. In this way, a plurality of strip pieces P are collected. Hereinafter, the rotary die cutter 70 and the method for manufacturing the strip pieces according to the second embodiment will be described in detail.

[0034] As shown in FIGS. 6, 7A, and 7B, the rotary die cutter 70 includes a die roll 72 and an anvil roll 74. The die roll 72 includes a die roll body 72A. The die roll body 72A has the same configuration as the die roll body 32A according to the first embodiment, except that the cross-sectional shape of the cutting edge 72Ac is triangular only in the vicinity of the cutting edge tip. The die roll 72 rotates in the direction of the arrow while pressing the strip material M via the elastic body sheet E with the die roll body 72A around the rotation axis A1 of the die roll body 72A. The anvil roll 74 has the same configuration as the anvil roll 34 according to the first embodiment and rotates in the same manner.

[0035] In the rotary die cutter 70, the width of the base end portion of the cutting edge 72Ac of the die roll body 72A is equal to or less than the width of the groove 34Ag of the anvil roll body 34A. The width of the groove 34Ag is set so that the clearance between the cutting edge of the cutting edge 72Ac and the edge of the groove 34Ag becomes as large as about five times the thickness of the thin strip material M, for example. The thickness t3 of the elastic body sheet E is thicker than the height of the cutting edge 72Ac. Since the elastic body sheet E is made of a resin sponge sheet, the hardness (Shore A) of the anvil roll elastic layer 34B is three times or more the hardness (Shore A) of the elastic body sheet E. The height of the cutting edge 72Ac and the clearance between the roll bodies 72A and 34A are set so that the depth at which the cutting edge 72Ac is pushed into the groove 34Ag becomes as large as about five times the thickness of the thin strip material M, for example.

[0036] In the method for manufacturing a thin strip piece according to the second embodiment, the rotary die cutter 70 is used, and the thin strip piece P is repeatedly punched out from the thin strip material M of the laminated sheet L (punching step). In the punching step, as shown in FIGS. 7A and 7B, while sandwiching the laminated sheet L between the outer peripheral surface 72As of the die roll body 72A and the outer peripheral surface 34Bs of the anvil roll elastic layer 34B, the die roll 72 and the anvil roll 74 are rotated in opposite directions to each other as indicated by the arrows. As a result, the laminated sheet L is passed between the die roll 72 and the anvil roll 74, so that the thin strip material M of the laminated sheet L is passed between the die roll 72 and the anvil roll 74. At this time, the thin strip material M is pressed by the die roll body 72A via the elastic body sheet E, and the thin strip material M is supported by the anvil roll elastic layer 34B, so that the thin strip material M is sandwiched between the elastic body sheet E and the anvil roll elastic layer 34B arranged in the adjacent regions on both sides of the base end portion of the cutting edge 72Ac of the outer peripheral surface 72As of the die roll body 72A, and the cutting edge 72Ac of the die roll body 72A is fitted into the groove 34Ag of the anvil roll body 34A with a gap S and pushed into the thin strip material M.

[0037] As a result, in the adjacent regions on both sides of the groove 34Ag of the anvil roll body 34A, the clamped portion Ms of the thin strip M sandwiched between the elastic sheet E and the anvil roll elastic layer 34B is constrained by the elastic forces of both the elastic sheet E and the anvil roll elastic layer 34B. At the same time, by protruding the cutting edge 72Ac of the die roll body 72A from the surface Es on the thin strip M side of the elastic sheet E, the pressing position Mp where the cutting edge 72Ac is pushed into the thin strip M is pushed down by the cutting edge 72Ac of the die roll body 72A. In this way, by applying a tensile stress due to restraint together with a tensile stress due to bending to the pressing position Mp of the thin strip M, the thin strip M is cut at the pressing position Mp.

[0038] Then, by continuously rotating the die roll 72 and the anvil roll 74, such cutting of the thin strip M occurs continuously, and by repeatedly punching out the thin strip pieces P from the thin strip M, a plurality of thin strip pieces P are manufactured.

[0039] According to the method for manufacturing a thin strip piece according to the second embodiment, as in the first embodiment, the thin strip M can be punched out by applying a tensile stress due to bending and a tensile stress due to restraint to the pressing position Mp of the thin strip M, so that damage to the rotary die cutter 70 can be suppressed.

[0040] Further, since the width of the base end portion of the cutting edge 72Ac of the die roll body 72A is equal to or less than the width of the groove 34Ag of the anvil roll body 34A, the clamped portion Ms of the thin strip M can be constrained by the elastic force of the elastic sheet E in the adjacent regions on both sides of the groove 34Ag of the anvil roll body 34A without delay with respect to the timing of pushing the cutting edge 72Ac of the die roll body 72A into the thin strip M. Therefore, the inflow of the thin strip M into the groove 34Ag can be avoided, and a tensile stress due to restraint can be applied to the pressing position Mp of the thin strip M with a magnitude sufficient for cutting.

[0041] Further, since the cutting blade 72Ac of the die roll body 72A is fitted into the groove 34Ag of the anvil roll body 34A with a gap S and pushed into the thin strip material M, the thin strip material M can be cut. Thus, similar to the first embodiment, the phase alignment of the die roll 72 and the anvil roll 74 becomes easy.

[0042] Furthermore, the hardness (Shore A) of the anvil roll elastic layer 34B is three times or more the hardness (Shore A) of the elastic body sheet E. Therefore, the hard anvil roll elastic layer 34B supports the thin strip material M and the soft elastic body sheet E presses the thin strip material M, so that the deformation of the clamped portion Ms of the thin strip material M can be suppressed and the clamped portion Ms of the thin strip material M can be firmly constrained. As a result, the thin strip material M can be surely cut at the pressing position Mp, and the thin strip piece P can be punched out from the thin strip material M with the accuracy of the planar shape of the cutting edge of the cutting blade 32Ac.

[0043] (Modification of the second embodiment) FIG. 8 is a process cross-sectional view schematically showing a main part of the punching process of the method for manufacturing a thin strip piece according to a modification of the second embodiment.

[0044] As shown in FIG. 8, the rotary die cutter 70V according to the modified example differs from the rotary die cutter 70 according to the second embodiment only in that the anvil roll 74 includes the anvil roll main body 34A and does not include the anvil roll elastic layer 34B. In the method for manufacturing a thin strip piece according to the modified example, unlike the method for manufacturing a thin strip piece according to the second embodiment, in the punching step, the rotary die cutter 70V is used, and while sandwiching the laminated sheet L between the outer peripheral surface 72As of the die roll main body 72A and the outer peripheral surface 34As of the anvil roll main body 34A, the die roll 72 and the anvil roll 74 are rotated in opposite directions as shown by the arrows, so that the thin strip material M of the laminated sheet L is passed between the die roll 72 and the anvil roll 74. At this time, the thin strip material M is pressed by the die roll main body 72A via the elastic body sheet E, and the thin strip material M is supported by the anvil roll main body 34A, so that the adjacent regions on both sides of the groove 34Ag on the outer peripheral surface 34As of the anvil roll main body 34A are in direct contact with the thin strip material M. While sandwiching the thin strip material M between the elastic body sheet E and the adjacent regions on both sides of the groove 34Ag on the outer peripheral surface 34As of the anvil roll main body 34A, the cutting edge 72Ac of the die roll main body 72A is fitted into the groove 34Ag of the anvil roll main body 34A with a gap S and pushed into the thin strip material M. Thereby, in the adjacent regions on both sides of the groove 34Ag of the anvil roll main body 34A, the sandwiched portion Ms of the thin strip material M sandwiched between the elastic body sheet E and the anvil roll main body 34A is constrained by the elastic force of the elastic body sheet E. At the same timing, by protruding the cutting edge 72Ac of the die roll main body 72A from the surface Es on the thin strip material M side of the elastic body sheet E, the pressing position Mp where the cutting edge 72Ac is pushed into the thin strip material M is pushed down by the cutting edge 72Ac of the die roll main body 72A. In this way, by applying a tensile stress due to bending and a tensile stress due to constraint to the pressing position Mp of the thin strip material M, the thin strip material M is cut at the pressing position Mp. Thereby, the thin strip piece P is punched out.

[0045] According to the method for manufacturing a thin strip piece according to the modified example, the same effects as those of the method for manufacturing a thin strip piece according to the second embodiment can be obtained, except for the effects obtained depending on the hardness conditions of the anvil roll elastic layer 34B.

[0046] Next, the details of each component in the method for manufacturing the strip piece according to the embodiment will be described.

[0047] 1. Rotary die cutter The rotary die cutter includes a die roll and an anvil roll. The die roll includes a die roll body having a cutting edge protruding from the outer peripheral surface with a shape corresponding to the periphery of the strip piece. The anvil roll includes an anvil roll body having a groove provided on the outer peripheral surface into which the cutting edge of the die roll body can be fitted with a gap.

[0048] The rotary die cutter is not particularly limited. For example, as in the first embodiment, the die roll may further include die roll elastic layers provided on both sides of the base end portion of the cutting edge on the outer peripheral surface of the die roll body. In this case, in the punching process described later, the die roll elastic layer may be used as the die roll side elastic body. Also, as the rotary die cutter, for example, as in the second embodiment, the die roll may not include such a die roll elastic layer. In this case, in the punching process described later, the elastic body sheet of the laminated sheet described later may be used as the die roll side elastic body.

[0049] The rotary die cutter is not particularly limited. For example, as in the first and second embodiments, the anvil roll may further include anvil roll elastic layers provided on both sides of the groove on the outer peripheral surface of the anvil roll body, or as in a modification of the first and second embodiments, the anvil roll may not include such anvil roll elastic layers.

[0050] The die roll body of the die roll is not particularly limited. For example, it is a cylindrical mold and is rotatably provided with its central axis as the rotation axis. The outer peripheral surface of such a die roll body may be, for example, a smooth cylindrical surface without irregularities, or may be one provided with convex or concave portions for fixing the die roll elastic layer on the cylindrical surface. The constituent material of the die roll body is not particularly limited. For example, alloy tool steel materials for cold work dies (material symbol: SKD) and high-speed tool steel (material symbol: SKH) specified in Japanese Industrial Standard JIS G 4403:2015, and high-speed tool steel (material symbol: HAP) manufactured by Hitachi Metals, Ltd., etc. can be mentioned.

[0051] Regarding the cutting edge of the die roll body, "having a shape corresponding to the periphery of the strip piece" means that the planar shape of the cutting edge tip in a plan view when the outer peripheral surface of the die roll body is developed into a plane is the same as the periphery of the strip piece. Note that the cutting edge may be a part of the die roll body or may be a member separate from the die roll body. When the cutting edge is a separate member, it is made of a hard material such as metal, for example.

[0052] The die roll elastic layer of the die roll is not particularly limited as long as it is provided on both sides of the base end portion of the cutting edge on the outer peripheral surface of the die roll body. However, it is preferably one that extends to the adjacent region of the base end portion of the cutting edge as in the first and second embodiments. Examples of the die roll elastic layer include those fixed and provided on the outer peripheral surface of the die roll body by adhesion, welding, mechanical joining, etc. The type of the die roll elastic layer is not particularly limited. For example, foam sheets or sponge sheets made of foamed resins such as urethane and ethylene vinyl acetate (EVA) can be mentioned. Note that the type of the elastic body sheet of the laminated sheet described later is the same as the type of the die roll elastic layer.

[0053] The anvil roll body of the anvil roll is not particularly limited. For example, it is a cylindrical mold and is rotatably provided with its central axis as the rotation axis. The outer peripheral surface of such an anvil roll body may be, for example, a smooth cylindrical surface without irregularities, or may be one provided with convex or concave portions for fixing the anvil roll elastic layer on the cylindrical surface. Regarding the constituent material of the anvil roll body, since it is the same as that of the die roll body, the description here is omitted.

[0054] Regarding the groove of the anvil roll body, "capable of being fitted in a state where the cutting edge of the die roll body has a gap" means that it has a shape and dimensions that can be fitted in a state where the cutting edge of the die roll body has a gap and can punch out the thin strip piece in the punching process. Note that the planar shape of the groove when the outer peripheral surface of the anvil roll body is developed into a plane is usually substantially equal to the contour shape of the thin strip piece and can be a shape that includes the planar shape of the cutting edge tip of the cutting edge when the outer peripheral surface of the die roll body is developed into a plane.

[0055] The anvil roll elastic layer of the anvil roll is not particularly limited as long as it is provided on both sides of the groove on the outer peripheral surface of the anvil roll body, but it is preferably one that extends to the adjacent regions on both sides of the groove as in the first and second embodiments. Examples of the anvil roll elastic layer include those fixed and provided on the outer peripheral surface of the anvil roll body by adhesion, welding, mechanical joining, etc. The type of the anvil roll elastic layer is not particularly limited, and examples include non-foamed resin sheets made of non-foamed resins such as urethane, rubber, and PET.

[0056] The width of the base end portion of the cutting edge of the die roll body is not particularly limited, but it is preferably equal to or less than the width of the groove of the anvil roll body as in the first and second embodiments. Here, the "width of the base end portion of the cutting edge" refers to the width of the base end portion of the cutting edge on the outer peripheral surface side of the die roll body and is the dimension in the direction perpendicular to the direction in which the cutting edge extends on the outer peripheral surface of the die roll body. Also, the "width of the groove" refers to the width of the opening of the groove of the anvil roll body and is the dimension in the direction perpendicular to the direction in which the groove extends on the outer peripheral surface of the anvil roll body.

[0057] The thickness of the die roll side elastic body is not particularly limited, but it is preferably thicker than the height of the cutting edge of the die roll body as in the first and second embodiments. This is because the thin strip can be firmly constrained by the die roll side elastic body at the timing of pushing the cutting edge of the die roll body into the thin strip. The thickness of the die roll side elastic body is preferably, for example, 4 times or less the height of the cutting edge, and more preferably 3 times or less the height of the cutting edge. The height of the cutting edge is, for example, about 0.2 mm. Here, the "thickness of the die roll elastic layer" refers to the dimension in the radial direction of the die roll body in a state where the die roll elastic layer is not elastically deformed. The "height of the cutting edge" refers to the dimension from the base end portion on the outer peripheral surface side of the die roll body of the cutting edge to the cutting edge tip in the radial direction of the die roll body.

[0058] The hardness of the anvil roll elastic layer is not particularly limited, but it is preferably harder than the hardness of the die roll side elastic body as in the first and second embodiments, and more preferably 3 times or more the hardness of the die roll side elastic body. This is because it can suppress the deformation of the clamped portion of the thin strip accompanying the pressing down of the pressing position of the thin strip M, and the clamped portion of the thin strip can be firmly constrained by the die roll side elastic body and the anvil roll elastic layer. Here, the "hardness" refers to, for example, that measured by the method specified in Japanese Industrial Standard JIS K 6253-3:2012 or JIS K 7312:1996. That is, for example, it is the durometer hardness (Shore A) of type A.

[0059] In addition, the "clearance between the cutting edge tip of the die roll body and the edge of the groove of the anvil roll body" refers to the dimension in the groove width direction between the cutting edge tip and the edge of the groove opening when the cutting edge tip comes to the deepest position inside the groove. The "depth to which the cutting edge is pushed into the groove" refers to the dimension from the groove opening surface to the cutting edge tip when the cutting edge tip comes to the deepest position inside the groove. The "clearance between the roll bodies" refers to the distance between the outer peripheral surface of the anvil roll body and the outer peripheral surface of the die roll body on a straight line orthogonal to the rotation axes of the anvil roll body and the die roll body.

[0060] 2. Method for manufacturing thin strip pieces The method for manufacturing thin strip pieces includes a punching step of punching thin strip pieces from a thin strip material using the rotary die cutter described above.

[0061] (1) Punching step In the punching step, when passing the thin strip material between the die roll and the anvil roll by rotating the die roll and the anvil roll in opposite directions to each other, while sandwiching the thin strip material between the die roll side elastic bodies arranged on both sides of the base end portion of the cutting edge on the outer peripheral surface of the die roll body and both sides of the groove on the outer peripheral surface of the anvil roll body, the cutting edge of the die roll body is inserted into the groove of the anvil roll body with a gap and pushed into the thin strip material to cut the thin strip material, thereby punching the thin strip pieces from the thin strip material.

[0062] When the die roll further includes the die roll elastic layer, in the punching step, as in the first embodiment, the die roll elastic layer may be used as the die roll side elastic body. In the punching step, as in the second embodiment, by passing a laminated sheet having the thin strip material and an elastic body sheet placed on the die roll side surface of the thin strip material between the die roll and the anvil roll to pass the thin strip material between the die roll and the anvil roll, the elastic body sheet may be used as the die roll side elastic body.

[0063] When the anvil roll further includes the anvil roll elastic layer, in the punching step, as in the first and second embodiments, the thin strip material may be sandwiched between the die roll side elastic body and the anvil roll elastic layer. When the anvil roll does not include the anvil roll elastic layer, in the punching step, as in the modified examples of the first and second embodiments, the thin strip material may be sandwiched between the die roll side elastic body and both sides of the groove on the outer peripheral surface of the anvil roll body so that both sides of the groove on the outer peripheral surface of the anvil roll body are in direct contact with the thin strip material.

[0064] (2) Others The thin strip is not particularly limited as long as it can be punched into thin strip pieces, but those having a Vickers hardness in the range of 300 HV or more and 900 HV or less are preferred, and among them, amorphous alloy thin strips and the like are preferred. This is because the effect of suppressing damage to the rotary die cutter is remarkable. The "Vickers hardness" refers to, for example, the Vickers hardness of the thin strip when the test force is 0.01 kgf and the load holding time is 10 seconds in the Vickers hardness test according to JIS Z2244 (2009).

[0065] The thickness of the thin strip is not particularly limited as long as it can be punched into thin strip pieces, and it varies depending on the type of the thin strip. For example, in the case of an amorphous alloy thin strip, it is in the range of, for example, 20 μm or more and 30 μm or less.

[0066] The thin strip pieces are not particularly limited, and examples thereof include thin strip pieces that form each layer of the laminated core such as a stator core or a rotor core in a motor for vehicle use or the like, and thin strip pieces obtained by further dividing the thin strip pieces in the circumferential direction.

Examples

[0067] Hereinafter, the manufacturing method of the thin strip pieces according to the embodiment will be described more specifically with reference to examples.

[0068] [Examples] First, the manufacturing method of the thin strip pieces according to the first embodiment was carried out on an actual machine. Specifically, first, as the rotary die cutter of the actual machine, one having the following configuration was prepared. And as the thin strip, an amorphous alloy thin strip (thickness: about 20 to 30 μm) was prepared.

[0069] (Configuration of Rotary Die Cutter) · Die roll body (die of upper roll) Outer diameter: predetermined value Height h of cutting edge: predetermined value Width W1 of base end portion of cutting edge: predetermined value (not more than width of groove of anvil roll body) · Die roll elastic layer (resin of upper roll) Thickness t1: predetermined value Hardness (Shore A): Predetermined value (1 / 3 or less of the anvil roll elastic layer) · Anvil roll body (lower roll mold) Outer diameter: Predetermined value Width W2 of groove: Predetermined value · Anvil roll elastic layer (resin of lower roll) Thickness t2: Predetermined value Hardness (Shore A): Predetermined value (3 times or more the hardness (Shore A) of the die roll elastic layer) · Rotary die cutter Clearance between the cutting edge of the die roll body and the edge of the groove of the anvil roll body: Set to be 5 times the thickness of the thin strip material Clearance d between roll bodies: Set so that the depth at which the cutting edge of the die roll body is pushed into the groove of the anvil roll body is 5 times the thickness of the thin strip material

[0070] Next, using an actual rotary die cutter, a test was conducted to repeatedly punch out strip pieces from an amorphous alloy thin strip under predetermined punching conditions (punching process). As a result, strip pieces could be repeatedly punched out from the amorphous alloy thin strip, and a plurality of strip pieces could be manufactured.

[0071] As described above in detail regarding the embodiments according to the present invention, the present invention is not limited to the above embodiments, and various design changes can be made without departing from the spirit of the present invention described in the claims.

Explanation of reference numerals

[0072] 30 Rotary die cutter 32 Die roll 32A Die roll body 32As Outer peripheral surface 32Ac Cutting edge 32B Die roll elastic layer 32Bs Outer peripheral surface 34 Anvil roll 34A Anvil roll body 34As Outer peripheral surface 34Ag Groove 34B Anvil Roll Elastic Layer 34Bs Outer Peripheral Surface M Thin Strip Material Mp Pressing Position P Thin Strip Piece 70 Rotary Die Cutter 72 Die Roll 72A Die Roll Body 74 Anvil Roll L Laminated Sheet E Elastomer Sheet Es Surface on the Die Roll Side

Claims

1. A method for manufacturing a thin strip piece, comprising a punching step of punching a thin strip piece from a thin strip using a rotary die cutter including a die roll and an anvil roll, wherein the die roll includes a die roll body having a cutting edge protruding from an outer peripheral surface thereof and having a shape corresponding to a periphery of the thin strip piece, the anvil roll includes an anvil roll body having a groove provided on an outer peripheral surface thereof, and the cutting edge of the die roll body fits into the groove in a state where there is a gap from the cutting edge to a bottom surface of the groove, in the punching step, when passing the thin strip between the die roll and the anvil roll by rotating the die roll and the anvil roll in opposite directions to each other, while sandwiching the thin strip between a die roll side elastic body disposed on both sides of a base end portion of the cutting edge on the outer peripheral surface of the die roll body and both sides of the groove on the outer peripheral surface of the anvil roll body, the cutting edge of the die roll body is fitted into the groove of the anvil roll body in a state where there is a gap from a pressing position where the cutting edge is pressed into the thin strip to the bottom surface of the groove of the anvil roll body, and the thin strip is cut by pushing the thin strip into the groove, thereby punching the thin strip piece from the thin strip. A method for manufacturing a thin strip piece, characterized in that.

2. The method for manufacturing a thin strip piece according to claim 1, wherein a width of a base end portion of the cutting edge of the die roll body is equal to or less than a width of the groove of the anvil roll body.

3. The die roll further includes a die roll elastic layer provided on both sides of a base end portion of the cutting edge on the outer peripheral surface of the die roll body, in the punching step, the die roll elastic layer is used as the die roll side elastic body. The method for manufacturing a thin strip piece according to claim 1 or 2, characterized in that.

4. In the punching step, the thin strip is passed between the die roll and the anvil roll by passing a laminated sheet having the thin strip and an elastic body sheet placed on a surface of the thin strip on the die roll side between the die roll and the anvil roll, and the elastic body sheet is used as the die roll side elastic body. The method for manufacturing a thin strip piece according to claim 1 or 2, characterized in that.

5. The anvil roll further includes an anvil roll elastic layer provided on both sides of the groove on the outer peripheral surface of the anvil roll body, The method for manufacturing a thin strip according to any one of claims 1 to 4, characterized in that, in the punching step, the thin strip is sandwiched between the die roll side elastic body and the anvil roll elastic layer.

6. The method for manufacturing a thin strip according to any one of claims 1 to 4, characterized in that, in the punching step, the thin strip is sandwiched between the die roll side elastic body and both sides of the groove on the outer peripheral surface of the anvil roll body so that both sides of the groove on the outer peripheral surface of the anvil roll body are in direct contact with the thin strip.

7. The method for manufacturing a thin strip according to any one of claims 1 to 6, characterized in that the thin strip has a Vickers hardness in the range of 300 HV or more and 900 HV or less.

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