JP2009066676A - Rotary die cutter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary die cutter which does not produce hairs and burrs, and surely cuts off a workpiece even when the workpiece having a metallic foil, such as the electrode sheet of a lithium ion secondary battery, is cut off. <P>SOLUTION: A die cut roll having a cutting edge projecting from its outer circumferential surface outward in the radial direction and an anvil roll 30 having a smooth outer circumferential surface are arranged such that the respective axes are in parallel with each other and the respective outer circumferential surfaces are opposed to each other. The machining of the workpiece is carried out by inserting the workpiece into the space between the die cut roll and the anvil roll 30. A resinoid film layer 35 made of the resin having the hardness lower than that of the outer circumferential surface 30A of the anvil roll 30 is formed on the outer circumferential surface 30A of the anvil roll 30. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rotary die cutter that processes a sheet-like workpiece with a blade shape and an anvil roll formed on the outer peripheral surface of a die cut roll, and in particular, like an electrode sheet of a lithium ion secondary battery. The present invention relates to a rotary die cutter suitable for cutting a workpiece having a metal foil.

Conventionally, as what cuts sheet-like workpieces, such as nonwoven fabric, paper, and films, into a predetermined shape, for example, as disclosed in Patent Document 1, a die-cut roll having a convex blade shape formed on the outer peripheral surface; A rotary die cutter having an anvil roll is provided.
In such a rotary die cutter, the workpiece interposed between the die cut roll and the anvil roll is cut by pressing the tip of the blade mold formed on the die cut roll against the outer peripheral surface of the anvil roll.

In recent years, in lithium ion secondary batteries widely used for notebook computers and mobile phones, an electrode sheet in which an electrode material such as carbon or lithium manganate is applied to the surface of a metal foil made of aluminum or copper is used. It has been. As a method for efficiently cutting such an electrode sheet into a predetermined shape, the above rotary die cutter has been attracting attention (for example, see Patent Document 2).
Japanese Patent Application Laid-Open No. 07-22798 JP 2002-110146 A

By the way, in the rotary die cutter, in order to improve the sharpness, it is processed so that the tip of the blade die is sharpened. A flat portion having a width of about a certain degree is necessarily formed. When cutting a metal foil having ductility such as aluminum or copper with such a blade shape, the metal foil is not broken by shearing and is crushed between the tip of the blade shape and the outer peripheral surface of the anvil roll. It sometimes deformed and could not be cut well.
In addition, there is a problem that the portion crushed by the tip of the blade mold and the outer peripheral surface of the anvil roll becomes a fragment, and it adheres to the cut surface of the work and becomes a beard, or the cut surface is frayed. there were.
Thus, it has been very difficult to cut a workpiece having a metal foil with a rotary die cutter.

  The present invention has been made in view of the above-described circumstances, and for example, even when a workpiece having a metal foil is cut like an electrode sheet of a lithium ion secondary battery, no whiskers or burrs are generated, and An object of the present invention is to provide a rotary die cutter capable of reliably cutting.

  In order to achieve the above object, a rotary die cutter according to the present invention includes a die cut roll having a blade shape that protrudes radially outward from an outer peripheral surface, and an anvil roll having a smooth outer peripheral surface. The rotary die cutter is arranged so that the axes are parallel and the outer peripheral surfaces of the rotary die cutter are opposed to each other, and the workpiece is inserted between the die cut roll and the anvil roll, thereby processing the workpiece. A resin film layer made of a resin whose hardness is lower than that of the outer peripheral surface of the anvil roll is formed on the outer peripheral surface of the anvil roll.

  According to the rotary die cutter having this configuration, the workpiece having the metal foil can be reliably cut into a blade shape by the blade die formed on the die cut roll entering the resin film layer of the anvil roll. Moreover, the piece of the work crushed by the flat part at the tip of the blade mold is not pushed into the resin film layer and adheres to the cut surface of the work, and the occurrence of whiskers and burrs can be suppressed.

Here, the resin film layer may be a resin film material that is detachably attached to the outer peripheral surface of the anvil roll.
In this case, the resin film layer can be easily replaced when the resin film layer is deteriorated by cutting with a blade mold or by embedding a work piece, ensuring good cutting conditions at all times. The workpiece can be reliably cut.

Further, the thickness t of the resin film layer may be set within a range of 1 × W ≦ t ≦ 20 × W with respect to the tip width W of the blade mold.
In this case, since the thickness t of the resin film layer is t ≧ 1 × W with respect to the tip width W of the blade mold, the blade mold and the tip width W of the blade mold pressed against the anvil roll The total thickness of the work and the resin film layer interposed between the anvil roll and the outer peripheral surface is increased. As a result, the cross section of the work and the resin film layer that is pressed by the blade mold (the cross section on which the shear stress acts) has a length in the pressing direction (the thickness direction of the work and the resin film layer) that is the tip of the blade mold. It becomes longer than the width W and becomes a vertically long rectangular shape in the pressing direction. Then, the section modulus Z of the cross section of the pressed portion (the section on which the shear stress acts) becomes larger than that in the case of a horizontally long rectangular shape, and the stress applied to the workpiece increases. Therefore, the workpiece is broken without being deformed, and the generation of burrs and burrs can be more reliably suppressed.
Furthermore, since the thickness t of the resin film layer is t ≦ 20 × W with respect to the tip width W of the blade mold, when the workpiece is pressed by the blade mold, the workpiece escapes to the resin film layer and is cut. It can be prevented from becoming impossible. That is, the work can be reliably cut by sandwiching the work and the resin film layer between the outer peripheral surface of the anvil roll having a higher hardness than the resin film layer and the blade mold.

Further, the die-cut roll is formed with a bearer portion that protrudes radially outward and is in sliding contact with the outer peripheral surface of the anvil roll, and the protruding height of the bearer portion is set higher than the protruding height of the blade shape. May be.
In this case, the blade mold will retreat inward in the radial direction from the bearer portion, and the blade mold will not penetrate in the thickness direction with respect to the resin film layer formed on the outer peripheral surface of the anvil roll. Deterioration of the film layer can be suppressed.

  According to the present invention, even if a workpiece having a metal foil is cut, such as an electrode sheet of a lithium ion secondary battery, a rotary die cutter that can be cut reliably without generating whiskers or burrs. Can be provided.

Embodiments of the present invention will be described with reference to the accompanying drawings.
1 to 5 show a rotary die cutter according to an embodiment of the present invention. The rotary die cutter 10 cuts an electrode sheet S of a lithium ion secondary battery in which an electrode material is applied on the surface of a metal foil such as aluminum or copper into a predetermined shape. In addition, the thickness X of this electrode sheet S (metal foil) is about 0.01 mm.
As shown in FIG. 1, the rotary die cutter 10 according to the present embodiment includes a die cut roll 20 and an anvil roll 30 that form a multistage columnar shape extending along axes M and N, respectively.

  The die cut roll 20 is made of a cemented carbide or the like, and shaft portions 21 extending along the axis M are formed at both ends thereof. A convex blade mold 22 is formed on the outer peripheral surface 20A of the die cut roll 20, and the outer diameter of the outer peripheral surface 20A is made one step larger than the outer diameter of the outer peripheral surface 20A with a gap between both ends of the blade mold 22. A bearer portion 24 is formed.

  The blade mold 22 is made of a hard material such as cemented carbide, and in the present embodiment, has a substantially square shape as shown in FIG. As shown in FIG. 3, the cross-sectional shape of the blade die 22 is formed such that its thickness gradually decreases as it goes to the radially outer side (tip side) of the die cut roll 20, and its radially outer end (tip). Is provided with a flat portion 23 having a width W. The width W of the flat portion 23 is about 0.01 mm to 0.1 mm, and in this embodiment, for example, W = 0.02 mm.

  The bearer portion 24 is configured to protrude radially outward from the outer peripheral surface 20A of the die cut roll 20, and the protrusion height from the outer peripheral surface 20 A of the die cut roll 20 is higher than the protrusion height of the blade die 22. Is set slightly higher. In the present embodiment, the difference between the protruding height of the bearer portion 24 and the protruding height of the blade mold 22 is set to be smaller than the thickness t of the resin film layer 35 described later.

The anvil roll 30 is made of a cemented carbide or a general steel material, and its outer peripheral surface 30A is formed in a cylindrical shape centering on the axis N and is a smooth surface. A shaft portion 31 extending along the axis N of the anvil roll 30 is formed at both ends of the anvil roll 30. A bearer receiving portion 34 that is in sliding contact with the bearer portion 24 is formed on the outer peripheral surface 30 </ b> A of the anvil roll 30.
A resin film layer 35 having a thickness t made of a resin having lower hardness than the outer peripheral surface 30A of the anvil roll 30 is formed on the outer peripheral surface 30A of the anvil roll 30.
The resin film layer 35 is a resin film material that is detachably mounted on the outer peripheral surface 30A of the anvil roll 30. In this embodiment, the outer periphery of the anvil roll 30 is formed using a heat-shrinkable tube made of fluororesin. A resin film layer 35 is formed on the surface 30A.

Here, the thickness t of the resin film layer 35 is in the range of 1 × W ≦ t ≦ 20 × W with respect to the width W of the flat portion 23 provided at the tip of the blade mold 22 of the die cut roll 20. Is set to In the present embodiment, the thickness t of the resin film layer 35 is 0.02 mm, and t = 1 × W.
Further, the hardness of the resin film layer 35 is set to 2H or more in pencil hardness.

  The aforementioned die-cut roll 20 and anvil roll 30 are arranged so that their outer peripheral surfaces 20A and 30A face each other and their axes M and N are parallel to each other. The shaft portion 21 of the die cut roll 20 and the shaft portion 31 of the anvil roll 30 are rotatably supported by bearing boxes (not shown), respectively, and are connected to a driving device (not shown). With this driving device, the die cut roll 20 and the anvil roll 30 are rotationally driven in the directions of arrows X and Y shown in FIG.

  In the rotary die cutter 10 having this configuration, the die cut roll 20 and the anvil roll 30 are rotated in the directions of arrows X and Y shown in FIG. 1, respectively, and the rotation directions X and Y are between the die cut roll 20 and the anvil roll 30. The electrode sheet S is inserted along the tangential direction, and a portion having the same shape (in the present embodiment, a substantially square shape) as the shape of the blade mold 22 is cut from the electrode sheet S.

Here, the schematic diagram at the time of cutting the electrode sheet S with the blade type | mold 22 is shown in FIG. 6A shows a cutting state by the rotary die cutter 10 according to the present embodiment, and FIG. 6B shows a cutting state by the conventional rotary die cutter 110 that does not have the resin film layer 35. ing.
In the conventional rotary die cutter 110, as shown in FIG. 6B, the width W = 0 of the flat portion 123 formed at the tip of the blade mold 122 with respect to the thickness X = 0.01 mm of the electrode sheet S. Since it is 0.02 mm, the cross section P (the cross section on which the shear stress acts) of the portion pressed by the tip (flat portion 123) of the blade mold 122 in the electrode sheet S has a horizontally long rectangular shape. At this time, the section modulus Z of the pressed in part of the cross section P (sectional shear stress is applied) becomes ^{Z = W × X 3/6} . Further, the electrode sheet S pressed by the blade mold 122 is deformed, so that breakage due to the shearing force occurs at two locations (C1 and C2 in FIG. 6B) at both ends of the cross section P of the pressed portion. It will be.

On the other hand, in the rotary die cutter 10 of this embodiment, as shown in FIG. 6A, the thickness X of the electrode sheet S = 0.01 mm and the thickness t = 0.02 mm of the resin film layer 35. Since the width W of the flat portion 23 formed at the tip of the blade die 22 is 0.02 mm with respect to the total thickness of 0.03 mm, the tip of the blade die 22 in the electrode sheet S and the resin film layer 35. The cross section P (the cross section on which the shear stress acts) of the portion pressed by the (flat portion 23) has a vertically long rectangular shape. At this time, the section modulus Z of the cross section P of the portion to be the press (sectional shear stress is applied) is larger than when cutting with Z = W × (X + t ) 3/6 , and the conventional rotary die cutter 110 Become. When the section modulus Z is large, the stress applied to this section also increases, so that the pressing force acts on this section without escaping. Further, since a large shearing stress acts on the electrode sheet S pressed by the blade mold 22, the fracture occurs at one place (C0 in FIG. 6A).

  The electrode sheet S cut in this way is wound around a suction roll (not shown) arranged behind the die cut roll 20 and the anvil roll 30, and thereby the inside of the cut part is extracted. The remaining part of the electrode sheet S is wound up and processed.

  According to the rotary die cutter 10 of the present embodiment configured as described above, the blade mold 22 formed on the die cut roll 20 is formed on the resin film layer 35 having a lower hardness than the outer peripheral surface 30A of the anvil roll 30. It is possible to reliably cut out the electrode sheet S having a metal foil into the shape of the blade mold 22. Further, a piece of the electrode sheet S (metal foil) crushed by the flat portion 23 at the tip of the blade mold 22 is pushed into the resin film layer 35, and does not adhere to the cut surface of the electrode sheet S, Generation of whiskers or burrs on the cut surface of the electrode sheet S can be suppressed.

  Further, since the resin film layer 35 is a resin film material that is detachably attached to the outer peripheral surface 30A of the anvil roll 30, the resin film layer 35 is cut when the blade 22 enters, or the electrode sheet S When a piece of (metal foil) is embedded and deteriorated, it becomes possible to easily replace the resin film layer 35, always ensuring good cutting conditions, and cutting the electrode sheet S over a long period of time. It can be done well.

Further, the thickness t of the resin film layer 35 is within the range of 1 × W ≦ t ≦ 20 × W with respect to the width W of the flat portion 23 formed at the tip of the blade mold 22. = 1 × W (0.02 mm), so that the outer peripheral surface 30A of the blade mold 22 and the anvil roll 30 is larger than the width W of the tip (flat portion 23) of the blade mold 22 pressed against the anvil roll 30. The total thickness t + X of the thickness X of the electrode sheet S and the thickness t of the resin film layer interposed therebetween is increased, and the tip (flat portion 23) of the blade mold 22 of the electrode sheet S and the resin film layer 35 is increased. The cross section P of the pressed portion (the cross section on which the shear stress acts) has a vertically long rectangular shape. This makes it possible to break the electrode sheet S without deforming it by applying a large shear stress to the cross-section P of the pressed portion. Further, when a large shear stress acts on the cross section P of the pressed portion, the fracture occurs at one place (C0 in FIG. 6A). Therefore, it is possible to reliably suppress the occurrence of burrs and burrs on the cut surface of the electrode sheet S.
Further, since the thickness t of the resin film layer 35 is t ≦ 20 × W, when the electrode sheet S is pressed by the blade mold 22, the electrode sheet S escapes to the resin film layer 35 and cannot be cut. Can be prevented.

  Furthermore, since the protruding height of the bearer portion 24 from the outer peripheral surface 20A is set slightly higher than the protruding height of the blade die 22, the blade die 22 is retracted radially inward from the bearer portion 24. Therefore, the blade mold 22 does not penetrate in the thickness direction with respect to the resin film layer 35 formed on the outer peripheral surface 30A of the anvil roll 30, and the deterioration of the resin film layer 35 can be suppressed. In the present embodiment, the difference between the protruding height of the bearer portion 24 and the protruding height of the blade mold 22 is set to be smaller than the thickness t of the resin film layer 35 to be described later. The surface of the layer 35 can be penetrated, and the electrode sheet S can be cut reliably.

In the present embodiment, since the resin film layer 35 is formed on the outer peripheral surface 30A of the anvil roll 30 using a heat-shrinkable tube made of fluororesin, the resin film layer 35 can be formed relatively easily. It becomes.
Furthermore, since the hardness of the resin film layer 35 is set to 2H or more in pencil hardness, the surface of the resin film layer 35 can be prevented from being damaged.

As mentioned above, although embodiment of this invention was described, this invention is not limited to this, It can change suitably in the range which does not deviate from the technical idea of the invention.
For example, although the resin film layer has been described as being made of a fluororesin, the present invention is not limited to this, and other resin materials such as PET, PVC, OPP, CPP, PE, and OPS may be used. . Moreover, you may use PTFE, PFA, FEP etc. as a fluororesin.

Moreover, although it demonstrated as what attached the heat shrinkable tube made from a fluororesin to the outer peripheral surface of the anvil roll, it is not limited to this, The resin material was applied to the outer peripheral surface of the anvil roll and cured. There may be.
Furthermore, although demonstrated as what cut | disconnects the electrode sheet S for lithium ion secondary batteries, it is not limited to this, You may use for the cutting | disconnection of other sheet | seat materials.

  Moreover, in this embodiment, although the blade shape was made into square shape, it is preferable to determine this shape arbitrarily according to the objective. Moreover, it is also possible to put a perforation of arbitrary shapes in a sheet-like workpiece | work by providing a cutting blade intermittently.

It is a perspective view of the rotary die cutter which is an embodiment of the present invention. It is a front view of the die cut roll with which the rotary die cutter shown in FIG. 1 was equipped. It is sectional drawing of the blade type | mold formed in the die-cut roll shown in FIG. It is a front view of the anvil roll with which the rotary die cutter shown in FIG. 1 was equipped. It is ZZ sectional drawing of the anvil roll shown in FIG. It is a schematic diagram which shows the state which cut | disconnects a workpiece | work with this embodiment and the conventional rotary die cutter.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Rotary die cutter 20 Die cut roll 20A outer peripheral surface 22 Blade type 23 Flat part 30 Anvil roll 30A Outer peripheral surface 35 Resin film layer

Claims (4)

A die-cut roll having a blade shape projecting radially outward from the outer peripheral surface and an anvil roll having a smooth outer peripheral surface so that the respective axes are parallel and the outer peripheral surfaces face each other. It is a rotary die cutter that is arranged to process the workpiece by inserting the workpiece between the die cut roll and the anvil roll,
The rotary die cutter characterized by the resin film layer which consists of resin whose hardness is lower than the outer peripheral surface of the said anvil roll being formed in the outer peripheral surface of the said anvil roll.   The rotary die cutter according to claim 1, wherein the resin film layer is a resin film material that is detachably attached to an outer peripheral surface of the anvil roll.   The thickness t of the resin film layer is set in a range of 1 × W ≦ t ≦ 20 × W with respect to the tip width W of the blade mold. The described rotary die cutter. The die cut roll is formed with a bearer portion that protrudes radially outward and is in sliding contact with the outer peripheral surface of the anvil roll,
The rotary die cutter according to any one of claims 1 to 3, wherein the protruding height of the bearer portion is set to be higher than the protruding height of the blade mold.

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