Manufacturing Apparatus and Method for Metal Foil and Laminated Core

Abstract

To provide a manufacturing device capable of manufacturing a laminate having sufficient performance with a high yield while performing continuous transportation efficiently.SOLUTION: A laminate manufacturing device includes a first cutting unit that cuts a strip so as to include a part of the contour of a thin piece and such that the outermost contour is an open curve, a first heat treatment unit that heats to include the interior of the outermost contour, a second cutting unit that cuts the strip such that the outermost contour is a closed curve to separate the strip and the thin piece, and a stacking unit that stacks the thin pieces in their thickness direction.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an apparatus and a method for manufacturing a thin sheet and a laminated core. In particular, the present invention relates to an apparatus and a method for manufacturing a metal thin sheet for a laminated core and a laminated core with good yield even when the material becomes brittle by a method such as heat treatment. The present invention also relates to a heat treatment apparatus used in this manufacturing apparatus.

Background Art

[0002] In recent years, with the Sustainable Development Goals (SDGs) in mind, efforts to address global environmental issues have been underway worldwide. For example, in automobiles, although petroleum-derived fuels are currently mainstream, in order to reduce dependence on such fuels, a shift from gasoline vehicles to electric vehicles and fuel cell vehicles is underway. In electric vehicles and fuel cell vehicles, since power is converted into motive power, it is necessary to improve the efficiency of this conversion. At the same time, in order to increase the degree of freedom in vehicle body design and reduce power consumption, weight reduction of the vehicle body is also required. In power conversion devices such as motors, power is converted into magnetic force and magnetic force is converted into motive power. When converting power into magnetic force, soft magnetic materials are used, but iron loss (reduction in conversion efficiency) occurs depending on the magnetic properties of the soft magnetic materials. In addition, since the amount of available magnetic force (magnetic flux) is limited by the saturation magnetic flux density of the soft magnetic material, the volume and weight of the soft magnetic material in the power conversion device tend to increase. Therefore, reducing the saturation magnetic flux density of the soft magnetic material and reducing iron loss are important for achieving the SDGs.

[0003] As the soft magnetic material, an electromagnetic steel sheet is mainly used, but a nanocrystalline strip is expected as a future soft magnetic material because of its thinness, low iron loss, and high saturation magnetic flux density. However, the nanocrystalline strip has problems such as high tissue dependence of iron loss and brittleness and difficulty in processing.

[0004] Therefore, when applying a nanocrystalline strip to a laminate such as a laminated core for a motor or a laminated iron core for a transformer, several problems are faced. For example, when the nanocrystalline strip is cut directly to obtain a metal thin sheet for the laminate, the metal thin sheet cracks and the yield is extremely low. Also, for example, after cutting an amorphous strip, which is a precursor of the nanocrystalline strip, to obtain a metal thin sheet for the laminate and heating this metal thin sheet to crystallize it, the crystallized thin strip is prone to cracking and continuous conveyance becomes difficult. On the other hand, when heating and crystallizing a laminate of amorphous strips, the structure inside the laminate becomes non-uniform and the iron loss of the laminate increases.

[0005] For example, as a method of processing a nanocrystalline strip into a predetermined shape, the method disclosed in Patent Document 1 can be mentioned, for example. In this method, in order to utilize brittle cutting, a cutter and a flexible base are used. However, this method has problems such as being able to perform only linear processing and having a poor yield when the cutting distance is long. Therefore, it is difficult to directly obtain a metal thin sheet for the laminate from the nanocrystalline strip by this method.

[0006] Also, as an apparatus for processing an amorphous strip or a nanocrystalline strip into a predetermined shape, the apparatuses disclosed in Patent Documents 2 to 4 can be mentioned, for example. In these apparatuses, a punch and a die are used from the viewpoint of facilitating mass production. However, when punching an amorphous strip to form a thin sheet, continuous conveyance of very thin sheets becomes extremely difficult. In addition, when heat-treating this thin sheet, the thin sheets sinter together or the thin sheet and the heater adhere to each other, making continuous processing difficult. When heat-treating after making the thin sheets into a laminate, the temperature inside the laminate becomes non-uniform and the performance of the laminate is significantly degraded. On the other hand, when punching a nanocrystalline strip, the strip cracks and the yield is extremely low.

[0007] As a heat treatment apparatus for manufacturing a nanocrystalline strip from an amorphous strip, for example, the apparatus disclosed in Patent Document 5 can be mentioned. In this apparatus, heat treatment is performed by bringing an alloy ribbon into contact with a heating member and a cooling member while conveying it. Further, in this apparatus, as an option, a suction structure and a pressing member are provided in the heating member and the cooling member. However, in this heat treatment apparatus, since the entire strip is heated, the entire strip becomes brittle and continuous processing becomes difficult. In particular, in order to improve the contact efficiency, when the tension of the strip is increased or the pressing force of the pressing member against the strip is increased, a strong shearing force acts on the strip, and cracks are likely to occur at important positions of the strip during crystallization. Furthermore, when a pressing member is used, it becomes difficult to control the heating rate due to the heat capacity of the pressing member.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0009] The present invention has been made in view of the above circumstances, and an object thereof is to provide a manufacturing apparatus and a manufacturing method capable of efficiently manufacturing a thin sheet or a laminate having sufficient performance with a high yield while performing continuous conveyance efficiently. Another object is to provide a heat treatment apparatus used in this manufacturing apparatus.

Means for Solving the Problems

[0010] [1] The manufacturing apparatus for a laminate according to one aspect of the present invention is a manufacturing apparatus for a laminate in which thin sheets are laminated in the thickness direction of the thin sheets, and includes an unwinding unit that unwinds a strip, and a first cutting unit that cuts the strip so as to include a part of the contour of the thin sheet and so that the outermost contour of the contour is an open curve, a first heat treatment unit that heats so as to include the inside of the outermost contour, a second cutting unit that cuts the strip so that the outermost contour is a closed curve to separate the strip and the thin sheet, a stacking unit that stacks the thin sheets in the thickness direction of the thin sheets, and a winding unit that winds up the strip from which the thin sheets have been separated. [2] In the first heat treatment unit of the manufacturing apparatus for a laminate according to [1] above, heating may be performed so as to include the entire thin sheet and so as to include a part in the width direction of the strip. [3] The second cutting unit of the manufacturing apparatus for a laminate according to [1] or [2] above includes a cutting blade, and the cutting edge shape of the cutting blade may be a line segment or an arc. [4] In the manufacturing apparatus for a laminate according to any one of [1] to [3] above, the first heat treatment unit may include a first plate, a second plate facing the first plate, and a drive unit that changes the distance between the first plate and the second plate. [5] The manufacturing apparatus for a thin sheet according to another aspect of the present invention includes an unwinding unit that unwinds a strip, a first cutting unit that cuts the strip so as to include a part of the contour of the thin sheet and so that the outermost contour of the contour is an open curve, a first heat treatment unit that heats so as to include the inside of the outermost contour, a second cutting unit that cuts the strip so that the outermost contour is a closed curve to separate the strip and the thin sheet, and a winding unit that winds up the strip from which the thin sheets have been separated. [6] The manufacturing apparatus for a thin sheet according to another aspect of the present invention includes an unwinding unit that unwinds a strip that is cut so as to include a part of the contour of the thin sheet and so that the outermost contour of the contour is an open curve, a first heat treatment unit that heats so as to include the inside of the outermost contour, a second cutting unit that cuts the strip so that the outermost contour is a closed curve to separate the strip and the thin sheet, and a winding unit that winds up the strip from which the thin sheet has been separated. [7] The heat treatment apparatus according to [5] or [6] above is a heat treatment apparatus that heat-treats a strip that is cut so as to include a part of the contour of a thin sheet and so that the outermost contour of the contour is an open curve, and heats so as to include the inside of the outermost contour. [8] The manufacturing method for a laminate according to another aspect of the present invention is a manufacturing method for a laminate in which thin sheets are laminated in the thickness direction of the thin sheets, and includes an unwinding step of unwinding a strip, a first cutting step of cutting the strip so as to include a part of the contour of the thin sheet and so that the outermost contour of the contour is an open curve, a first heat treatment step of heating so as to include the inside of the outermost contour, a second cutting step of cutting the strip so that the outermost contour is a closed curve to separate the strip and the thin sheet, a laminating step of stacking the thin sheets in the thickness direction of the thin sheets, and a winding step of winding up the strip from which the thin sheets have been separated. [9] The manufacturing method for a thin sheet according to another aspect of the present invention includes an unwinding step of unwinding a strip, a first cutting step of cutting the strip so as to include a part of the contour of the thin sheet and so that the outermost contour of the contour is an open curve, a first heat treatment step of heating so as to include the inside of the outermost contour, a second cutting step of cutting the strip so that the outermost contour is a closed curve to separate the strip and the thin sheet, and a winding step of winding up the strip from which the thin sheet has been separated. [Advantages of the Invention]

[0011] The manufacturing apparatus and method for a thin sheet or laminate according to an aspect of the present invention can manufacture a thin sheet or laminate having sufficient performance with a high yield while efficiently performing continuous conveyance.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2A

Figure 2B

Figure 2C

Figure 2D

Figure 2E

Figure 2F

Figure 2G

Figure 2H

Figure 2I

Figure 2J

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Mode for Carrying Out the Invention

[0013] Next, embodiments of the present invention will be described in detail.

[0014] (1. Manufacturing Apparatus for Laminate) Fig. 1 shows a manufacturing apparatus 1 for a laminate according to an embodiment of the present invention. The manufacturing apparatus 1 according to the present embodiment can manufacture a nanocrystal laminate U in which thin flakes T having a predetermined shape are laminated from an amorphous strip S. The manufacturing apparatus 1 for a laminate according to the present embodiment includes an unwinding unit 2, a first cutting unit 3, a first heat treatment unit 4, a second cutting unit 5, a lamination unit 6, and a winding unit 7. The unwinding unit 2 unwinds the amorphous strip S from a coil of the amorphous strip S that can be used as a nanocrystal strip by crystallization. The first cutting unit 3 cuts a part of the contour along the contour (shape) of the thin flake T from the amorphous strip S. The first heat treatment unit 4 heats a part of the amorphous strip S to crystallize it. The second cutting unit 5 cuts the remaining part of the contour of the thin flake T to form the thin flake T (nanocrystal thin flake) from the amorphous strip S. The lamination unit 6 laminates the thin flakes T in the thickness direction of the thin flakes T to form the nanocrystal laminate U from the thin flakes T. The winding unit 7 winds up the remaining amorphous strip S (residual material) and conveys the amorphous strip S in a pair with the unwinding unit.

[0015] The unwinding unit 2 unwinds the amorphous strip S from the coil of the amorphous strip S. This unwinding unit 2 pairs with the winding unit 7 to convey the amorphous strip S on the line. The unwinding unit 2 may be provided with a tension control unit to apply an appropriate tension to the amorphous strip S. Also, in order to control the conveyance speed of the amorphous strip S, the unwinding unit 2 may be provided with a speed control unit. It is preferable that the conveyance of the amorphous strip S is intermittently performed by this speed control unit. Further, in order to reduce the possibility that the amorphous strip S breaks due to dimensional changes (for example, thermal expansion or deformation due to stress) of the amorphous strip S on the line, the unwinding unit 2 may be provided with a slack control unit that gives slack to the amorphous strip S. Also, since the conveyance accuracy may decrease when the thickness of the coil decreases according to the amount of unwinding, it is preferable that the unwinding unit 2 is provided with a roll that adjusts the height to be constant between the unwinder of the unwinding unit 2 and the first cutting unit 3. Further, when moving the line, a stainless steel foil may be used as a dummy material, and the amorphous strip S may be connected to this dummy material to start the operation of the line. This connection method is not particularly limited. When welding is used for the connection, the unwinding unit 2 may be provided with a welding unit. The welding method is preferably, for example, spot welding.

[0016] The first cutting unit 3 cuts a part of the contour along the contour of the thin sheet T from the amorphous strip S. When the shape of the thin sheet T is the shape shown in FIG. 2A, a part of the outermost contour a is cut. For example, the solid line portion in FIG. 2B is cut, and the broken line portion in FIG. 2B is left uncut. At this time, it is preferable to cut all the contours b other than the outermost contour a. Further, when the amorphous strip S is heat-treated by the first heat treatment unit 4, in order to reduce the heat influence (mainly the heat influence due to heat conduction) on the amorphous strip S that is wound up as a residual material, or to relieve the strain caused by the volume change between the heat treatment region and the non-heat treatment region, a gap may be provided by cutting outside the outermost contour a. However, the amorphous strip S is cut so that the outer cutting portion does not completely surround the outermost contour a. That is, the first cutting unit 3 cuts the amorphous strip S so that the portion corresponding to the thin sheet T of the amorphous strip S and the portion corresponding to the residual material of the amorphous strip S are connected. The cutting length of the outermost contour a is preferably 80% or more of the perimeter of the outermost contour a.

[0017] Also, the shape of the thin sheet T is not particularly limited. For example, the thin sheet T may have a shape as shown in FIG. 2C. Note that the position where the outermost contour a is left without being cut is not particularly limited. For example, it may be the position of the dotted round mark c, the position of the dotted round mark d, or the position of the dotted round mark e. Also, for example, as shown in FIGS. 2E and 2F, the thin sheet T may not be point-symmetrical with respect to the center (center of gravity). That is, the thin sheet T may have a certain directionality. In this case, the first cutting unit 3 may rotate the cutting shape by a specific angle with respect to the center (center of gravity). The first cutting unit 3 may be provided with a rotation unit for this rotation. This rotation helps to increase the stacking factor of the laminate U when the thickness of the amorphous strip S is non-uniform. The rotation angle may be 90°, 180°, or any other arbitrary angle. The rotation angle may be adjusted as appropriate while measuring the non-uniformity of the thickness. Also, in order to realize the rotation, a plurality of cutting shapes may be prepared in advance. Further, elements that break the symmetry indicated by the dotted round marks in FIGS. 2E and 2F may be appropriately added in advance so as to give symmetry according to the rotation angle. For example, when the rotation angle is 90°, four such elements may be prepared. Also, as shown in FIG. 2G, in a transformer or a motor, a core combining split cores may be used in some cases. In the case of a split core as shown in FIG. 2H, for example, the solid line portion in FIG. 2I is cut, and the broken line portion in FIG. 2I is left without being cut. Note that in a split core, unevenness may be combined to facilitate the connection of the cores. For example, the shape of the split core may be a shape as shown in FIG. 2J.

[0018] The shape left without cutting is preferably a part of a straight line or a part of an arc. Also, the position left without cutting is preferably a position where the performance is less likely to deteriorate even if the cutting accuracy decreases in the target application. Note that the amorphous strip S becomes brittle due to crystallization. Therefore, when cutting by the second cutting unit 5 described later, cracks are likely to occur in a direction different from the cutting direction. Thus, it is preferable to add a cut (for example, a half cut or a scratch) up to the middle in the thickness direction at the position left without cutting. The size of this cut is preferably 80% or less of the thickness of the amorphous strip S, more preferably 70% or less, and most preferably 60% or less in order to prevent it from being cut during conveyance. On the other hand, from the viewpoint of smoothing the cutting surface during cutting by the second cutting unit, the size of the cut is preferably 10% or more, more preferably 20% or more, and most preferably 30% or more. Also, at the position left without cutting, notches may be added to the ends of the above-mentioned part of the straight line or part of the arc (connection part). These notches are preferably at both ends of the connection part. The size of these notches is preferably such that the total length of the notches is 50% or less of the width of the connection part, more preferably 20% or less, in order to prevent it from being cut during conveyance. From the viewpoint of the notches functioning efficiently, the size of the notches is preferably 5% or more, more preferably 10% or more.

[0019] In addition, in order to ensure the punching accuracy by the second cutting unit 5 described later and to flexibly control the tension applied to the amorphous strip S, it is preferable to form positioning holes x in the amorphous strip S. The cutting method may be, for example, punching using a die and a punch, cutting with a blade, wire cutting, cutting by etching, or cutting by laser irradiation. From the viewpoint of production efficiency, it is preferable that the cutting method is punching using a die and a punch. Further, if the amorphous strip S is contaminated during cutting, there is a possibility that the amorphous strip S may be altered during heat treatment due to this contamination. For example, when a substance containing carbon such as lubricating oil is used for cutting, the amorphous strip S may be carburized during heat treatment. Therefore, the first cutting unit 3 may be provided with a cleaning unit that removes contaminants.

[0020] The first heat treatment unit 4 heats and crystallizes a part of the amorphous strip S (for example, the shaded area in FIG. 1). The heating area preferably includes all of the area of the thin piece T (for example, inside the outermost contour a). Further, it is preferable that the heating area avoids the area outside the thin piece T (for example, outside the outermost contour a). In particular, it is preferable that the heating area does not cross the entire width direction of the amorphous strip S. That is, it is preferable that the heating area is a part of the width direction of the amorphous strip S. Examples of the heating method include a method of bringing a high-temperature plate into contact with or close to the amorphous strip S, a method of blowing a high-temperature gas onto the amorphous strip S, and a method of bringing the amorphous strip S into contact with a high-temperature liquid.

[0021] Among these, from the viewpoint of ensuring the cleanliness of the surface of the amorphous thin strip S, it is preferable to heat the amorphous strip S by blowing a high-temperature gas onto the amorphous strip S. From the viewpoint of forming an insulating film on the surface of the amorphous thin strip S, it is preferable to heat the amorphous strip S by bringing the amorphous strip S into contact with a high-temperature liquid. From the viewpoint of enhancing the flatness of the amorphous thin strip S or utilizing a higher heating rate, it is preferable to heat the amorphous strip S by bringing a high-temperature plate into contact with the amorphous strip S.

[0022] When increasing the maximum heating rate, it is preferable to bring high-temperature plates into contact with both sides of the amorphous strip S. In this case, both sides of the plates are brought into contact with the amorphous strip S almost simultaneously. To achieve such double-sided contact, the first heat treatment unit 4 may include plates 41, 42, heaters 43, 44 that contact the plates 41, 42 and heat the plates 41, 42, and moving mechanisms 47, 48. Further, the first heat treatment unit 4 may include heat insulation units as optional units 45, 46 between the heaters 43, 44 and the moving mechanisms 47, 48. In addition, the moving mechanism may include pressure sensors (load sensors) as optional units 45, 46 for controlling the heating rate. For example, this contact time lag may be 0 to 10 ms. As a method for measuring the time lag, in addition to the method of determining the time lag from the pressure change of the above pressure sensor, an electrical method can be adopted. For example, an electrical circuit is formed between the first plate (upper plate) 41 and the amorphous strip S, an electrical circuit is formed between the second plate (lower plate) 42 and the amorphous strip S, the first plate 41 and the second plate 42 are electrically insulated, and the contact and non-contact between the plates 41, 42 and the amorphous strip S are configured as switches. Also, by setting the temperature of the first plate 41 and the temperature of the second plate 42 to different temperatures and slightly shifting the time when the first plate 41 contacts the amorphous strip S and the time when the second plate 42 contacts the amorphous strip S, heat treatment at two or more stages of temperature or heat treatment with a temperature gradient can be performed.

[0023] In addition, in the method of bringing the amorphous strip S into contact with the high-temperature plates 41 and 42 or the high-temperature liquid, gas may be trapped between the plates 41 and 42 or the liquid and the amorphous strip S, resulting in uneven heating and a decrease in the heating rate. Therefore, in order to reduce the trapped gas, the first heat treatment unit 4 may be provided with a pressure reducing mechanism. Further, in order to be able to remove the trapped gas, a flow path may be provided in the plates 41 and 42. In order to forcibly remove the gas and increase the contact efficiency, a pressure reducing mechanism may be provided in the flow path. Further, a flow path for circulating a refrigerant may be provided in the plates 41 and 42. By flowing the refrigerant through this flow path after the contact heating, rapid cooling after rapid heating can be achieved.

[0024] In addition, the material of the plates 41 and 42 is preferably a material with high thermal conductivity. This thermal conductivity is preferably 0.8 W / (m·K) or more. In particular, from the viewpoint of achieving stable rapid heating, the material of the plates 41 and 42 is preferably any one of copper (thermal conductivity of 350 W / (m·K) or more), aluminum (thermal conductivity of 200 W / (m·K) or more), and an alloy of copper and aluminum. Further, from the viewpoint of performing temperature measurement without time lag by the radiation thermometer 49, the material of one of the plates 41 or 42 is preferably quartz (thermal conductivity of 0.8 W / (m·K) or more). In this case, as shown in FIG. 3, in order to secure the region 4a through which infrared rays pass, it is preferable that the shapes of the one-sided heater 42 and the plate 41 have holes 4a (for example, are ring-shaped). The quartz and the heater 43 may be brought into contact with each other, and after the quartz is sufficiently heated, the heater 43 may be separated from the region through which infrared rays pass. On the other hand, from the viewpoint of weather resistance, the material of the plate is preferably alumina (thermal conductivity of 10 W / (m·K) or more) or stainless steel (thermal conductivity of 10 W / (m·K) or more).

[0025] In the crystallization of the amorphous strip S, it is desirable that the crystallization rate of the amorphous strip S can be controlled. The detection wavelength of the radiation thermometer is preferably in the range of 1.8 to 2.7 μm. In particular, it is more preferable that this wavelength is in the range of 2.2 to 2.4 μm, and most preferably 2.3 μm.

[0026] Also, when prioritizing the conveyance and positioning of the amorphous strip S, which is more stable than the heating rate, the amorphous strip S may be fixed by contacting it with a low-temperature plate, and a high-temperature plate may be contacted from one side. In this case, if quartz is used for the low-temperature plate, temperature measurement can be performed by a radiation thermometer without time lag. Also, from the viewpoints of heating rate and thermal efficiency, it is preferable to use a material with low thermal conductivity and small heat capacity for the low-temperature plate. For example, it is preferable that the thermal conductivity is 1.2 W / (m·K) or less.

[0027] Furthermore, when the amorphous strip S is heated in an atmosphere containing oxygen, oxidation proceeds from the surface of the amorphous strip S, and an oxide film is formed on the surface of the amorphous strip S. This oxide film insulates between the layers of the laminate and reduces losses. However, when the thickness of the oxide film increases, the saturation magnetic flux density decreases. Therefore, it is preferable that the first heat treatment unit 4 has a gas replacement mechanism. The type of gas is not particularly limited. For example, an inert gas such as argon (Ar) or nitrogen (N2), or a 0.1 to 3.0 volume% H2-Ar gas or 0.1 to 3.0 volume% H2-N2 gas in which 1 to 3 volume% (based on 0 °C and 1 atm) of hydrogen (H2) is mixed with these inert gases is preferable. Also, it is preferable that the dew point is low, for example, the dew point may be 0 °C or lower.

[0028] In addition, the first heat treatment unit 4 may be provided with a positioning unit (not shown) that accurately controls the heating region by passing a shaft through the positioning hole x. At this time, the first heat treatment unit 4 may be provided with a cooling unit (not shown) around the shaft so that the shaft is not heated.

[0029] The second cutting unit 5 cuts the remainder of the contour of the thin sheet T (particularly, the remainder of the outermost contour a) to form the thin sheet T (nanocrystalline thin sheet) from the amorphous strip S. For example, the second cutting unit 5 cuts the broken line portions in FIGS. 2B, 2D, and 2I. That is, the second cutting unit 5 cuts the amorphous strip S such that the portion corresponding to the thin sheet T of the amorphous strip S and the portion corresponding to the remaining material of the amorphous strip S are separated. In order to simultaneously remove the heat affected zone, it may be cut outside the outermost contour a. On the other hand, in order to prevent the removed heat affected zone from being mixed into the thin sheet T, only the remainder of the contour of the thin sheet T may be cut.

[0030] Further, in order to ensure the punching accuracy or to flexibly control the tension applied to the amorphous strip S, the second cutting unit 5 may be provided with a positioning unit. This positioning unit may accurately control the cutting position by passing a shaft through the positioning hole x. The cutting method may be, for example, punching using a die and a punch, cutting with a blade, wire cutting, cutting by etching, or cutting by laser irradiation. From the viewpoint of production efficiency, it is preferable that the cutting method is punching using a die and a punch or cutting with a blade.

[0031] Note that the amorphous strip S becomes brittle due to crystallization. Therefore, cracks are likely to occur in a direction different from the cutting direction during cutting. Therefore, it is preferable to cut in such a way as to fold the cut portion of the amorphous strip S. Also, if the amorphous strip S is contaminated during cutting, there is a possibility that the amorphous strip S may be altered due to this contamination. For example, when a substance containing carbon such as lubricating oil is used for cutting and the remaining material is heat-treated and used, the amorphous strip S (remaining material) may be carburized. Therefore, the second cutting unit 5 may be provided with a cleaning unit for removing contaminants.

[0032] The lamination unit 6 laminates the thin sheets T in the thickness direction of the thin sheets T to form a nanocrystal laminate U from the thin sheets T. When the user processes the laminate U, the laminate U can be used as a product as it is. Note that a core material may be inserted into the center of the laminate U so that the lamination position of the laminate U does not shift.

[0033] Also, when the thin sheet T is point-symmetrical with respect to the center (center of gravity), a trans-lamination unit that laminates the thin sheets T while changing the rotation angle may be provided. This trans-lamination unit helps to increase the stacking factor of the laminate U when the plate thickness of the amorphous strip S is non-uniform. The rotation angle may be 90°, 180°, or any other arbitrary angle. The rotation angle may be adjusted as appropriate while measuring the non-uniformity of the thickness.

[0034] Furthermore, for example, as shown in FIGS. 2E and 2F, when the thin sheet T is not point-symmetrical with respect to the center (center of gravity), that is, when the thin sheet T has a certain directionality, an alignment unit 61 that aligns the directions of the thin sheets T in the same direction may be provided. Also, the lamination unit 6 may be provided with a cleaning unit that removes contaminants. Furthermore, when bonding the laminate U, the lamination unit 6 may be provided with an adhesive unit 62 that bonds the layers of the laminate U. The adhesive unit introduces an adhesive between the layers of the laminate U. The type of the adhesive is not particularly limited. The adhesive may be an organic material or an inorganic material. In addition, the lamination unit 6 may be provided with a second heat treatment unit 63 for removing the strain during cutting, ensuring the viscosity of the adhesive, or curing the adhesive. This second heat treatment unit 63 may be independent of the lamination unit 6.

[0035] The winding unit 7 winds up the remaining amorphous strip material S (the remaining material), and together with the unwinding unit, conveys the amorphous strip material S. The winding unit 7 may be provided with a tension control unit in order to apply an appropriate tension to the amorphous strip material S. Further, in order to control the conveyance speed of the amorphous strip material S, the winding unit 7 may be provided with a speed control unit. Furthermore, in order to reduce the possibility that the amorphous strip material S breaks due to dimensional changes (for example, deformation due to thermal expansion or stress) on the line of the amorphous strip material S, the winding unit 7 may be provided with a slack control unit that gives slack to the amorphous strip material S. Also, since the conveyance accuracy may decrease when the thickness of the coil decreases according to the amount of unwinding, it is preferable that the winding unit 7 includes a roll that adjusts the height to be constant between the unwinder of the winding unit 7 and the second cutting unit 5 or the third cutting unit 9 described later.

[0036] The manufacturing apparatus 1 of the laminate may further include a cooling unit 8 that cools the heated amorphous strip material S between the first heating unit 4 and the second cutting unit 5. This cooling unit 8 may cool the amorphous strip material S by bringing a plate close to or into contact with the amorphous strip material S, or may bring a fluid such as a gas or a liquid or a flowing material such as a powder into contact with the amorphous strip material S. The temperature of the material (the aforementioned plate, fluid, flowing material) used for cooling is not particularly limited and may be room temperature. In order to prevent a temperature rise, the cooling unit 8 itself may be cooled by a method such as water cooling, oil cooling, or air cooling. For example, the cooling unit 8 may be provided with a circulation unit for water cooling or oil cooling, or may be provided with a fan for air cooling. The range to be cooled may be the region heated by the first heat treatment unit 4, or may be the entire region as shown by the shaded region in FIG. 1. The first heat treatment unit and the cooling unit 8 may be combined to flexibly control the heating region and the cooling region.

[0037] The manufacturing apparatus 1 of the laminate may further include a third cutting unit 9 for removing the heat-affected portion of the amorphous strip S between the second cutting unit 5 and the winding unit 7. This third cutting unit 9 separates the connection portion between the thin sheet T and the amorphous strip S that becomes the residue, making the amorphous strip S easier to recycle for other uses. The cutting method may be, for example, punching using a die and a punch, cutting with a blade, wire cutting, cutting by etching, or cutting by laser irradiation. From the perspective of production efficiency, it is preferable that the cutting method is punching using a die and a punch or cutting with a blade. This third cutting unit 9 may be provided with a cleaning unit for removing contaminants.

[0038] The manufacturing apparatus 1 of the laminate may further include a winding unit immediately after the first cutting unit 3. Also, the manufacturing apparatus 1 of the laminate may further include an unwinding unit immediately before the first heat treatment unit 4. In such a configuration, the first cutting unit 3 and the first heat treatment unit 4 can be carried out at different bases, and the productivity can be flexibly changed.

[0039] The manufacturing apparatus 1 of the laminate of this embodiment can be suitably used to manufacture a laminate U made of a nanocrystalline material by crystallizing an amorphous strip. In this case, it is particularly suitable to use the laminate for a stator or a rotor of a motor. However, it can be used without being limited to this application. In particular, it is suitable to apply the manufacturing apparatus 1 of the laminate to materials that become brittle when heated.

[0040] (2. Manufacturing method of the laminate) The method for manufacturing a laminate according to another embodiment of the present invention includes, as shown in the flowchart of FIG. 3, an unwinding step S1 of moving an amorphous strip (thin strip), a first cutting step S2 of cutting the thin strip without separating it into a thin piece and a remaining material (in a state where the thin piece and the remaining material are connected), a first heat treatment step S5 of heating a portion corresponding to the thin piece in the thin strip to crystallize or inhomogenize it, a second cutting step S6 of cutting the thin strip so that it is separated into a thin piece and a remaining material (in a state where the thin piece and the remaining material are not connected), a laminating step S7 of laminating the thin pieces in the thickness direction of the thin piece, and a winding step S12 of recovering the remaining material. Note that the method for manufacturing the amorphous strip is not limited. The amorphous strip may be manufactured by a single roll method, a twin roll method, a spraying method, a plating method, or a vapor deposition method.

[0041] In the unwinding step S1, the thin strip is moved toward the first cutting step S2. In this unwinding step S1, the unwinding unit 2 and its associated configuration in the above-described embodiment can be preferably used. In this unwinding step S1, it is preferable to control the tension applied to the thin strip and the conveyance speed of the thin strip. Depending on the situation of subsequent steps, in the unwinding step S1, the thin strip is conveyed intermittently.

[0042] In the first cutting step S2, the thin strip is cut without separating it into a thin piece and a remaining material. In this first cutting step S2, the first cutting unit 3 and its associated configuration in the above-described embodiment can be preferably used. In this first cutting step S, from the viewpoint of productivity, the faster the cutting speed, the more desirable. For example, the cutting speed may be 1.0 to 100,000 times / second. Also, from the viewpoint of performing sufficient heat treatment, the cutting speed may be reduced. For example, the cutting speed may be 0.004 to 1.0 times / second.

[0043] In the first heat treatment step S5, the portion corresponding to the thin flakes in the thin strip is heated to cause crystallization or inhomogenization. In this first heat treatment step S5, the first heat treatment unit 4, the cooling unit 8, and their associated configurations in the above-described embodiment can be preferably used. In this first heat treatment step S5, from the viewpoint of productivity, crystallization may be stopped at the level of solute inhomogenization or nucleation. For example, the crystallization rate may be 0.1 to 50%, or may be 5 to 20%. The crystallization rate is determined by a differential scanning calorimeter (DSC). In this measurement by DSC, the heat generation amount (calculated from the peak area) due to the formation of the metal crystal phase in the DSC curve obtained from a material that can be substantially judged as an amorphous single phase (for example, a material after liquid quenching and before crystallization) is defined as the total heat generation amount ΔH(all) (that is, 100%). Similarly, the heat generation amount (calculated from the peak area) due to the formation of the metal crystal phase in the DSC curve obtained from the material to be measured is defined as the remaining heat generation amount ΔH(bal). The crystallinity is obtained by dividing the value obtained by subtracting the remaining heat generation amount ΔH(bal) from the total heat generation amount ΔH(all) by the total heat generation amount ΔH(all) and multiplying by 100 (that is, the crystallinity is calculated by (△H(all) - ΔH(bal)) / ΔH(all) × 100). Also, from the same viewpoint, the inhomogenization (for example, precipitation of copper clusters) for heterogeneous nucleation may be stopped at a level without crystallization. For example, as confirmation of inhomogenization, copper clusters can be detected by an atom probe. Also, for example, regarding the degree of inhomogenization, the first crystallization temperature described later may be reduced by 10°C or more from before the heat treatment. The upper limit of this reduction amount is not particularly limited, but may be 150°C. In these cases, it is preferable to perform heat treatment in a later step to complete crystallization. Also, in the first heat treatment step S5, from the viewpoint of the completeness of crystallization, the crystallization rate may be 80 to 100%, or may be 95 to 100%.

[0044] The heating rate is preferably 100 °C / min or higher, more preferably 100 °C / sec or higher, and most preferably 1000 °C / sec or higher from the viewpoint of improving the frequency of nucleation. The upper limit of the heating rate is not particularly limited. From the viewpoint of controllability, the heating rate may be 100000 °C / sec or lower. The temperature to be reached by heating may be any temperature equal to or higher than the temperature at which crystallization starts when a part of the thin strip is crystallized. For example, the temperature reached may be a temperature equal to or higher than the first crystallization temperature (the temperature at which a phase of a body-centered cubic structure of Fe or an Fe-Si system or a structure similar thereto precipitates) and equal to or lower than the second crystallization temperature (the temperature at which a compound phase precipitates). This first crystallization temperature is determined by heating a sample of about 20 mg at a heating rate of 40 °C / min by differential scanning calorimetry (DSC). Therefore, when the heating rate is high, both the first crystallization temperature and the second crystallization temperature are lower than the temperatures determined by this DSC. Therefore, the temperature reached may be in the range from 20 °C lower than the first crystallization temperature to 20 °C lower than the second crystallization temperature. Also, when a part of the thin strip is homogenized, the temperature reached may be any temperature equal to or higher than the temperature at which the diffusion of atoms in the thin strip becomes sufficient. This temperature varies greatly depending on the chemical composition of the thin strip. For example, the temperature reached may be 250 °C or higher. Also, when crystallization is to be avoided, the temperature reached may be in the range from 100 °C lower than the first crystallization temperature to 20 °C lower than the first crystallization temperature. The heating time can be determined according to the degree of crystallization rate. For example, the heating time (the time during which the sample is at a temperature higher than the first crystallization temperature) may be 0.01 sec to 250 sec. Also, the cooling rate is not particularly limited. From the viewpoint of maintaining the structure after heat treatment as it is, the cooling rate is preferably 100 °C / min or higher, more preferably 100 °C / sec or higher, and most preferably 1000 °C / sec or higher. From the viewpoint of controllability, the cooling rate may be 100000 °C / sec or lower. Also, from the viewpoint of preventing the introduction of strain associated with the freezing of the structure into the structure after heat treatment, the cooling rate is preferably less than 100 °C / min, more preferably 1 °C / min or lower, and most preferably 0.1 °C or lower. In the above description, the number of heat treatment steps is one, but the heat treatment may have a multi-step temperature setting.

[0045] In the second cutting step S6, cutting is performed so that the thin strip is separated into a thin piece and a residual material. In this first heat treatment step S5, the second cutting units 5 and their associated configurations in the above-described embodiment can be preferably used. In this second cutting step S6, from the viewpoint of productivity, the faster the cutting speed, the more desirable. For example, the cutting speed may be 1.0 to 100,000 times / second. Also, from the viewpoint of sufficiently performing the heat treatment, the cutting speed may be slowed down. For example, the cutting speed may be 0.004 to 1.0 times / second.

[0046] In the laminating step S7, the thin pieces are laminated in the thickness direction of the thin pieces. In this laminating step S7, the laminating unit 6 and their associated configurations in the above-described embodiment can be preferably used.

[0047] When joining the thin pieces to form a laminate, the method for manufacturing a laminate according to the present embodiment may include an adhesion step S8 or S10 after the laminating step S7. In this case, the surface of the thin piece may be surface-modified so that the adhesive and the thin piece adhere closely. It is preferable to use a silane coupling agent as this surface modifier. Also, in order to control the rate of surface modification and resin curing, a catalyst such as a reaction accelerator or a reaction retarder may be used. Further, for example, the organic adhesive may be an epoxy resin or an acrylic resin. Also, for example, the inorganic adhesive may be water glass or a low melting point ceramic (for example, a phosphate glass, a borate glass, a vanadate glass).

[0048] In order to remove the strain generated in the thin sheet by cutting or to sufficiently advance the crystallization, the method for manufacturing a laminate according to the present embodiment may include a second heat treatment step S9 after the lamination step S7. The order of the second heat treatment step S9 and the adhesion step S8 or S9 can be appropriately selected. When an organic adhesive is used, it is preferable that the second heat treatment step S9 is after the adhesion step S8. Also, when the second heat treatment step S9 is before the adhesion step S10, it is preferable to perform the heat treatment at a temperature lower than the heat resistance temperature of the organic resin. On the other hand, when an inorganic adhesive and a low melting point ceramic are used, it is preferable that the second heat treatment step S9 is after the adhesion step S10. The adhesive preferably has the same coefficient of thermal expansion as that of the thin sheet (for example, the difference in the coefficients of thermal expansion of both at 300 °C is 30% or less of the coefficient of thermal expansion of the thin sheet). When sufficiently advancing the crystallization, the temperature reached by heating may be in the range from 20 °C lower than the first crystallization temperature to 20 °C lower than the second crystallization temperature. In this case, the heating time (the time during which the sample is at a temperature higher than the first crystallization temperature) may be from 0.01 second to 10,000 seconds. The heating rate and the cooling rate are not particularly limited. For example, the heating rate and the cooling rate may be 0.1 °C / min or more, 1.0 °C / min or more, or 100 °C / min or more. Also, for example, the heating rate and the cooling rate may be 1000 °C / min or less, 500 °C / min or less, or 200 °C / min or less. When the difference in the coefficients of thermal expansion between the adhesive and the thin sheet is large, it is preferable to set the cooling rate to 1.0 °C / min in order to reduce the strain caused by thermal expansion. The method for manufacturing a laminate according to the present embodiment may include these heat treatment steps and adhesion steps a plurality of times.

[0049] In the winding step S12, the residual material is recovered. In this winding step S12, the winding unit 7 and its associated components in the above-described embodiment can be preferably used. In this winding step S12, it is preferable to control the tension applied to the thin strip and the conveyance speed of the thin strip. Depending on the situation of the previous step, in the winding step S12, the residual material is intermittently recovered.

[0050] The method for manufacturing a laminate according to this embodiment may include an intermediate unwinding step S3 and an intermediate winding step S4 between the first cutting step S2 and the first heat treatment step S5. With such a configuration, the first cutting step S2 and the first heat treatment step S5 can be performed at different bases, and the productivity can be flexibly changed.

[0051] The method for manufacturing a laminate according to this embodiment may include a third cutting step S11 between the second cutting step S6 and the winding step S12. In this third cutting step S11, the third cutting unit 9 and their associated configurations in the above-described embodiment can be preferably used.

[0052] (3. Manufacturing apparatus for metal thin sheets) As a modification of the manufacturing apparatus 1 for a laminate according to the above-described embodiment, the lamination unit 6 can be omitted from the manufacturing apparatus 1 for a laminate to obtain a manufacturing apparatus for metal thin sheets.

[0053] (4. Manufacturing method for metal thin sheets) As a modification of the manufacturing method for a laminate according to the above-described embodiment, the lamination step S7 and subsequent steps can be omitted to obtain a manufacturing method for metal thin sheets.

[0054] (5. Heat treatment apparatus) As a modification of the manufacturing apparatus 1 for a laminate according to the above-described embodiment, a part including the first heat treatment unit 4 can be used from the manufacturing apparatus 1 for a laminate to obtain a heat treatment apparatus.

[0055] (6. Recycling method for waste materials) Regarding waste materials, they can be reused for manufacturing another thin sheet or used as pulverized powder. Also, the chips generated in the first cutting step S2 of the manufacturing method for a laminate according to the above-described embodiment can be used as pulverized powder.

[0056] The present invention is not limited to the above-described embodiments, and it should be understood that design changes, improvements, etc. can be appropriately made based on the ordinary knowledge of those skilled in the art without departing from the spirit of the present invention.

Example

[0057] A high-temperature planar heating element RS1010 (100 mm × 100 mm × 0.8 mm) manufactured by Sakaguchi Denki Co., Ltd. was fixed between metal plates having the same area as this heating element to prepare two heater units. Each heater unit was fixed to another 100 mm × 300 mm metal plate so as to maintain a space for heat insulation between the heater unit and the metal plate, and the end of this metal plate was fixed to the end of a pantograph type jack. A jig for fixing the sample and the sample were fixed to the center of the pantograph type jack. A full screw and a handle were attached to one side of the 100 mm × 300 mm metal plate to make the pantograph type jack movable. By this mechanism, the pantograph type jack was moved so that the two heater units and the sample came into contact simultaneously. The outline of this mechanism is shown in FIG. 5.

[0058] First, a part of an amorphous ribbon (FeBSiPCCu-based composition) having a width of 60 mm was trimmed to prepare a sample (hereinafter referred to as a trim sample) having a region where crystallization was required and a region where crystallization was not required. The region where crystallization was required was set as the inner region of a circle with a diameter of 50 mm, and the outer region was set as the region where crystallization was not required. In order to reduce the amount of temperature rise in the outer region, a gap of about 2 mm was provided outside the circumference along the circumference of this circle. Further, 4 to 12 connecting portions of 1 to 3 mm were appropriately provided in the gap so that the inner region and the outer region were not separated.

[0059] The shape of the surface of the heater unit in contact with the sample is a circle with a diameter of 52 mm (partial heating). The sample was installed so that the center of this circle and the center of the inner region coincided. Then, the temperatures of the two heater units were adjusted to 450 ° C., and these heater units were brought into contact with the trim sample to heat the trim sample in the air for 1 second. The load at the time of contact was 20 kgf.

[0060] As a result, the surface was sufficiently oxidized in the internal region, while hardly oxidized in the external region separated by a gap. This indicates that the internal region was preferentially heat-treated. Also, no wrinkles were observed on the sample, and it had a good appearance.

[0061] As a reference example, a 60-mm thin strip (hereinafter referred to as the untrimmed sample) was heated at 450°C for 1 second and 20 seconds without being processed. As a result, as shown in Fig. 6 (left: 1 second; right: 20 seconds), in addition to the internal region, surface oxidation also progressed in the external region around the internal region. Also, wrinkles occurred in the external region due to the difference in volume change between the internal region and the external region. From this, it can be seen that by providing a gap along the periphery of the internal region, partial heat treatment can be performed while maintaining the quality of the thin strip.

[0062] Furthermore, heat treatment at a temperature of 450°C was performed on the trimmed sample with heating times of 5 seconds and 20 seconds (heating rate from 200°C to 400°C: approximately 430°C / second). A tensile test was conducted on this trimmed sample using a digital force gauge FGJN-50 manufactured by Nidec-Shimpo Corporation, and the tensile force when the trimmed sample was cut was measured. The results are shown in Table 1. As can be understood from Table 1 and Fig. 7, it can be seen that by setting the heating time short, the tensile force can be maintained equivalent to that of the thin strip before heat treatment. Also, the shape of the surface in contact with the sample was changed to a flat plate that was in full contact with the sample, and the same experiment was conducted with a heating time of 1 second (full surface heating). As a result, a part of the trimmed sample burned and the internal region was damaged. Therefore, the experiments at heating times of 5 and 20 seconds were omitted. The tensile force of the trimmed sample obtained by full surface heating for 1 second was 2.1 N. The result is shown as an open triangle in Fig. 7. As can be understood from Fig. 7, it can be seen that partial heat treatment can bring the strength of the thin strip as close as possible to the state for heat treatment. Although production by conveyance greatly contributes to productivity improvement, since the strength of the thin strip greatly affects the yield of thin strip conveyance by rolls, it can be understood that the combination of partial heat treatment and conveyance produces a great synergistic effect in terms of achieving both productivity and yield.

[0063] In addition, in order to measure the crystallinity and coercivity of the samples at heating times of 0, 1, 5, and 20 seconds, a heat treatment experiment was conducted using an untrimmed sample that could be cut into an appropriate shape and amount for measurement. For the measurement of crystallinity, a differential scanning calorimeter DSC8500 manufactured by PerkinElmer was used. The amount of the sample was set to 20 mg, and the heating rate was set to 40 °C / min. The heat generation amount (calculated from the peak area) due to the formation of the metal crystal phase in the DSC curve obtained from the sample with a heating time of 0 seconds was defined as the total heat generation amount ΔH(all) (i.e., 100%). Similarly, the heat generation amount (calculated from the peak area) due to the formation of the metal crystal phase in the DSC curve obtained from the sample after heat treatment was defined as the remaining heat generation amount ΔH(bal). The crystallinity was obtained by dividing the value obtained by subtracting the remaining heat generation amount ΔH(bal) from the total heat generation amount ΔH(all) by the total heat generation amount ΔH(all) and multiplying by 100 (i.e., the crystallinity was calculated by (ΔH(all) - ΔH(bal)) / ΔH(all) × 100). For the measurement of coercivity, an automatic measurement coercimeter K-HC-1000 manufactured by Tohoku Special Steel Co., Ltd. was used.

[0064]

Table 1

[0065] As shown in Table 1 and Fig. 8, it can be seen that by appropriately changing the heat treatment time, the crystallinity can be adjusted from 0% to nearly 100%. Also, since the coercivity can be kept small, it can be seen that a structure in which fine crystal phases are dispersed in the amorphous phase can be stably obtained. Such a structure can maintain the crystal phase in a fine state even when the crystallization is further enhanced in the subsequent heat treatment, which facilitates the subsequent process design (for example, the restrictions on the conditions of the subsequent heat treatment are reduced).

[0066] In addition, when contacting, two K-type thermocouples with a thickness of 100 μm were inserted between the two heater units, and the load at the time of contact was changed to confirm the correlation between the load and the heating rate (the maximum value of multiple measurements) in the temperature range of 250 to 400 °C. As a result, as shown in Fig. 9, it was confirmed that a higher heating rate can be obtained by changing the load.

[0067] From the above, by using the manufacturing apparatus and manufacturing method according to the foregoing embodiment, it is possible to proceed with the production design while maintaining the productivity while keeping the target tact time without degrading the performance of the produced laminate.

Explanation of Signs

[0068] 1 Manufacturing apparatus for laminate 2 Unwinding unit 3 First cutting unit 4 First heat treatment unit 5 Second cutting unit 6 Laminating unit 7 Winding unit 41 Plate 42 Plate 43 Heater 44 Heater 47 Moving mechanism 48 Moving mechanism S Amorphous strip S T Flake U Laminate

Claims

1. An apparatus for manufacturing a laminate in which sheets are laminated in the thickness direction of the sheets, a pay-out unit for paying out a strip, a first cutting unit for cutting the strip so as to include a part of the contour of the sheet and so that the outermost contour of the contour is an open curve, a first heat treatment unit for heating excluding the outside of the outermost contour and including the inside of the outermost contour, a second cutting unit for cutting the strip so that the outermost contour becomes a closed curve to separate the strip and the sheet, a stacking unit for stacking the sheets in the thickness direction of the sheets, a winding unit for winding up the strip from which the sheet has been separated, An apparatus for manufacturing a laminate comprising the above.

2. The apparatus for manufacturing a laminate according to claim 1, wherein in the first heat treatment unit, heating is performed so as to include the entire sheet and so as to include a part in the width direction of the strip.

3. The apparatus for manufacturing a laminate according to claim 1 or 2, wherein the second cutting unit includes a cutting blade, and the cutting edge shape of the cutting blade is a line segment or an arc.

4. The apparatus for manufacturing a laminate according to any one of claims 1 to 3, wherein the first heat treatment unit includes a first plate, a second plate facing the first plate, and a drive unit for changing the distance between the first plate and the second plate.

5. An apparatus for manufacturing a sheet, a pay-out unit for paying out a strip, a first cutting unit for cutting the strip so as to include a part of the contour of the sheet and so that the outermost contour of the contour is an open curve, a first heat treatment unit for heating excluding the outside of the outermost contour and including the inside of the outermost contour, A second cutting unit that cuts the strip so that the outermost contour becomes a closed curve and separates the strip and the sheet; A winding unit that winds up the strip from which the sheet has been separated; A sheet manufacturing apparatus comprising the above. **Claim 6** A sheet manufacturing apparatus, An unwinding unit that unwinds a cut strip so as to include a part of the contour of the sheet and so that the outermost contour of the contour becomes an open curve; A first heat treatment unit that heats the strip excluding the outside of the outermost contour and including the inside of the outermost contour; A second cutting unit that cuts the strip so that the outermost contour becomes a closed curve and separates the strip and the sheet; A winding unit that winds up the strip from which the sheet has been separated; A sheet manufacturing apparatus comprising the above. **Claim 7** A sheet manufacturing apparatus comprising a heat treatment unit, The cut strip is continuously conveyed to the heat treatment unit so as to include a part of the contour of the sheet and so that the outermost contour of the contour becomes an open curve, The strip is continuously conveyed from the heat treatment unit in order to cut the strip so that the outermost contour becomes a closed curve and separate the strip and the sheet. A sheet manufacturing apparatus, Here, The heat treatment unit heats the strip excluding the outside of the outermost contour and including the inside of the outermost contour. A sheet manufacturing apparatus. **Claim 8** A method for manufacturing a laminate in which sheets are laminated in the thickness direction of the sheets, An unwinding step of unwinding a strip; A first cutting step of cutting the strip so as to include a part of the contour of the sheet and so that the outermost contour of the contour becomes an open curve; A first heat treatment step of heating while excluding the outside of the outermost contour and including the inside of the outermost contour; A second cutting step of cutting the strip so that the outermost contour becomes a closed curve to separate the strip and the sheet; A stacking step of stacking the sheets in the thickness direction of the sheets; A winding step of winding the strip from which the sheet has been separated; A method for manufacturing a laminate including the above steps.

9. A method for manufacturing a sheet, comprising: An unwinding step of unwinding a strip; A first cutting step of cutting the strip so as to include a part of the contour of the sheet and so that the outermost contour of the contour becomes an open curve; A first heat treatment step of heating while excluding the outside of the outermost contour and including the inside of the outermost contour; A second cutting step of cutting the strip so that the outermost contour becomes a closed curve to separate the strip and the sheet; A winding step of winding the strip from which the sheet has been separated; A method for manufacturing a sheet comprising the above steps.

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