JP2012166896A - Web winder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a web winder capable of excellently winding a web even when manufacturing a plurality of winding rolls with mutually different outer diameters at the same time.SOLUTION: This web winder 1 includes: an unwinding shaft 10 to be attached with an unwinding roll Ro; a slitter 30 dividing a web W wound out from the unwinding roll Ro into two; a winding shaft 40 winding the divided web W to form two winding rolls Rw, Rw; and touch rolls 50, 50 applying winding tension Tw responding to a pressure F to the web W of each winding roll Rw by applying the pressure F to the winding rolls Rw, Rw. In the touch roll 50, following increase of a winding diameter D from starting winding of the web W, the winding tension Tw of the web W in the winding roll Rw is gradually reduced, and when the winding diameter D becomes a predetermined size or more, the pressure F is changed so that the winding tension Tw of the web W in the winding roll Rw is gradually increased.

Description

  The present invention relates to a web winding device that divides a web into a plurality of strips and winds the divided web.

  2. Description of the Related Art Conventionally, a web winding device is widely known in which a web such as an electrode member used in a lithium ion secondary battery is conveyed while being supported by a plurality of rollers, and is wound after being divided into a plurality of strips.

  In the web winding device as described above, the web is wound well by bringing the touch roll into contact with the winding start portion of the web (winding roll) wound around the core with a predetermined pressure. The technique to take is publicly known (for example, refer to Patent Document 1).

  However, as the outer diameter of the take-up roll increases with the passage of time, the pressure with which the touch roll presses the take-up roll also changes, and the web is taken up with an excessive tension (winding tightening). Or there exists a possibility that the axial deviation (winding deviation) of the winding roll due to an increase in the outer diameter of the winding roll may occur.

  Further, since the conventional web winding device is not based on the premise that a plurality of winding rolls having different outer diameters are simultaneously manufactured, when a plurality of winding rolls having different outer diameters are simultaneously manufactured, It is difficult to wind the web well every time.

JP-A-7-267437

  This invention makes it a subject to provide the web winding apparatus which can wind up a web favorably also when producing the several winding roll from which an outer diameter mutually differs simultaneously.

  The web winding device of the present invention is a web winding device that winds the web wound from a winding roll formed by winding a web, the winding shaft to which the winding roll is attached, A slitter that divides the web to be unwound from the unwinding roll by rotating the unwinding shaft into a plurality of strips, and a plurality of webs that have been split into a plurality of strips by the slitter on the outer peripheral surface. The winding roll is in contact with the winding shaft formed along the axial direction and the outer peripheral surface of the plurality of winding rolls, and a predetermined pressing force is applied to each winding roll to thereby apply the pressing roll. It comprises a plurality of touch rolls that apply tension according to pressure to the webs of the respective winding rolls, and each touch roll has an outer diameter of the winding roll that comes into contact with the web from the beginning of winding. ,gradually When the web tension in the winding roll decreases and the outer diameter of the winding roll that comes into contact becomes larger than a predetermined value, the web tension in the winding roll gradually increases. Change the pressure.

  In the web winding device of the present invention, it is preferable that the outer diameter of each of the winding rolls is calculated based on an angle at which the touch roll in contact with the winding roll swings with the change.

  According to the present invention, even when a plurality of winding rolls having different outer diameters are produced at the same time, the web can be wound well.

The side view which shows the web winding apparatus which concerns on this invention. The top view which shows the web winding apparatus which concerns on this invention. The figure which shows the calculation aspect of a winding diameter. The figure which shows the preferable change of winding tension according to winding diameter. The figure which shows the change of the pressing force of the touch roll with respect to a winding roll. The figure which shows the change of the pressing force of a touch roll at the time of producing the winding roll of a comparatively small winding diameter.

Below, with reference to drawings, web winding device 1 which is one embodiment of the web winding device concerning the present invention is explained.
The web winding device 1 is a device that transports the web W along its longitudinal direction and winds it after dividing it into a plurality of strips.
The web W is a thin film such as an electrode member used for a lithium ion secondary battery.
Note that the vertical direction in FIG. 1 is defined as the vertical direction of the web winding device 1.

  As shown in FIGS. 1 and 2, the web winding device 1 includes an unwinding shaft 10, a plurality of guide roll guide rolls 20, 20..., A slitter 30, a winding shaft 40, and a touch roll 50. 50 and a control device 60 are provided.

The unwinding shaft 10 is a shaft that is rotationally driven around a shaft center by a predetermined motor (not shown), and is attached with an unwinding roll Ro.
The unwinding roll Ro is a member in which the web W is wound around a cylindrical core Co and is a processing target of the web winding device 1. The unwinding roll Ro rotates along with the rotation of the unwinding shaft 10 by fixing the unwinding shaft 10 inside the winding core Co.

  The guide rolls 20, 20... Are rollers that can rotate around the axis. The guide rolls 20, 20... Form the web W conveyance path by supporting the web W unwound from the unwinding roll Ro at a plurality of positions. Thus, the web W is transported in a state where a predetermined tension (hereinafter referred to as “transport tension T0”) is applied. The transport tension T0 is determined in advance by experiments or the like, and is kept constant when the web winding device 1 is in operation.

The slitter 30 is a member that divides the web W into two along the longitudinal direction, and is disposed on the conveyance path of the web W. The slitter 30 includes an upper blade 31 disposed above the web W and a lower blade 32 disposed below the web W.
Each of the upper blade 31 and the lower blade 32 is a disk-shaped blade that is rotationally driven around an axis by a predetermined motor (not shown), and continuously cuts the web W being conveyed from above and below. . The web W divided into two by the upper blade 31 and the lower blade 32 is conveyed by different paths until reaching the winding shaft 40.

The winding shaft 40 is a shaft such as a friction shaft that is rotationally driven around a shaft center by a predetermined motor (not shown), and is attached with the two winding cores Cw and Cw spaced apart from each other along the axial direction. It is done. The web W is unwound from the unwinding roll Ro when the unwinding shaft 10 and the winding shaft 40 are rotationally driven in predetermined directions (arrow directions in FIG. 1), and the web is divided into two by the slitter 30. W is wound around the cores Cw and Cw, respectively. Thus, the two winding rolls Rw and Rw are formed on the outer peripheral surface of the winding shaft 40 along the axial direction.
Each winding roll Rw is a member formed by winding one and the other of the webs W divided into two by the slitter 30 onto a cylindrical winding core Cw. It is a product made in

The touch roll 50 abuts on the take-up roll Rw and applies a predetermined pressure F (hereinafter referred to as “pressing force F”) to the take-up roll Rw, whereby a tension Tw (hereinafter, referred to as “pressing force F”) is applied. It is a roller for applying “winding tension Tw”) to the web W of the winding roll Rw. The touch roll 50 is disposed on the most downstream side in the conveyance path of the web W such that the contact position between the outer circumferential surface of the touch roll 50 and the outer circumferential surface of the winding roll Rw is the winding start portion of the web W on the winding roll Rw. The touch roll 50 applies a pressing force F to the take-up roll Rw when its outer peripheral face comes into contact with the outer peripheral face of the take-up roll Rw. When the pressing force F is applied to the take-up roll Rw by the touch roll 50, the web W is wound as the take-up roll Rw with the take-up tension Tw corresponding to the press force F in a state where the transport tension T0 is kept constant. Will be taken. In addition, the touch roll 50 is provided according to the number of the winding rolls Rw. That is, the web winding device 1 in the present embodiment is provided with two touch rolls 50 and 50.
The touch roll 50 is connected to the motor 52 via the arms 51 and 51.

  Each of the arms 51 and 51 is a rod-like member that supports the touch roll 50 so that the touch roll 50 can rotate about its axis at one end thereof. The other ends of the arms 51 and 51 are fixed to a rotating shaft 52 a of the motor 52.

  The motor 52 is a motor for pressing the touch roll 50 against the outer peripheral surface of the take-up roll Rw via the arms 51 and 51. The other ends of the arms 51 and 51 are fixed to the rotation shaft 52a of the motor 52, and the rotation of the rotation shaft 52a of the motor 52 causes the arms 51 and 51 to rotate. 50 will swing. Thus, the motor 52 can abut the touch roll 50 on the take-up roll Rw via the arms 51 and 51.

  The motor 52 includes an encoder (not shown) for detecting the rotation angle of the rotation shaft 52a. The motor 52 is electrically connected to the control device 60, and the control device 60 can acquire information such as the rotation angle of the rotation shaft 52a detected by the encoder.

The control device 60 is electrically connected to the motors 52 and 52, and the motors 52 and 52 are controlled in accordance with the outer diameter D (hereinafter referred to as “winding diameter D”) of each winding roll Rw that changes every moment. It is a device to control.
Hereinafter, only members related to one winding roll Rw, that is, one touch roll 50 and motor 52 will be described.

The control device 60 can calculate the winding diameter D of each winding roll Rw based on the rotation angle of the rotating shaft 52a of the motor 52.
As shown in FIG. 3, the web W is wound around the core Cw from the state where the touch roll 50 is in contact with the core Cw, that is, the initial state where the web W is not wound around the core Cw. When the touch roll 50 is in contact with the take-up roll Rw, the swing angle of the touch roll 50 is θ, and the length of the arm 51 is L. X can be expressed as in Equation 1 below.
[Equation 1]
X = 2 * L * sin (θ / 2)

Furthermore, when the outer diameter of the winding core Cw is D0, the winding diameter D can be expressed as the following formula 2.
[Equation 2]
D ≒ D0 + 2 * X

Thus, the control device 60 acquires the rotation angle of the rotating shaft 52a from the encoder of the motor 52, calculates the swing angle θ of the touch roll 50, and geometrically winds based on Equation 1 and Equation 2. The diameter D can be calculated.
Thereby, the winding diameter D can be calculated with high accuracy without using an ultrasonic sensor or the like that is easily affected by disturbance.

The control device 60 controls the motor 52 so that the winding tension Tw becomes a desired value according to the winding diameter D calculated as described above.
As shown in FIG. 4, the winding tension Tw is preferably set so as to gradually decrease as the winding diameter D increases.
This is because, in the winding roll Rw, it is possible to prevent the occurrence of adverse effects caused by winding the web W at a winding tension Tw that is more than necessary, so-called winding tightening.
Further, the winding tension Tw is preferably set so as to gradually increase when the winding diameter D becomes larger than a predetermined value (the final stage of winding the web W on the winding roll Rw). .
This is because, in the winding roll Rw having a relatively large winding diameter D, it is possible to prevent so-called winding deviation in which the web W is shifted in the axial direction of the winding roll Rw. Here, the winding diameter D of “larger than a predetermined size” is a winding diameter D that is large enough to cause a winding shift in the winding roll Rw.

The winding tension Tw changes according to the pressing force F of the touch roll 50 against the winding roll Rw and is also affected by the transport tension T0. Therefore, using the pressing force F and the transport tension T0, Can be expressed as:
In addition, Tw (D) in Equation 3 indicates a winding tension (set value) determined according to the winding diameter D as shown in FIG. 4, and μ indicates a dynamic friction coefficient of the web W.
[Equation 3]
Tw (D) = T0 + μ * F

By converting Equation 3, the pressing force F can be expressed as in Equation 4 below.
[Equation 4]
F = (Tw (D) −T0) / μ

  As shown in FIG. 4, Tw (D) in Equation 4 is a preset value (target value) set in advance, and the transport tension T0 is also a constant value determined in advance through experiments or the like as described above. Therefore, the pressing force F corresponding to the winding tension Tw can be calculated based on Equation 4.

  In this way, the control device 60 controls the motor 52 in accordance with the winding diameter D calculated sequentially, and the winding tension Tw becomes a desired value (see FIG. 4) as shown in FIG. The pressing force F of the touch roll 50 against the winding roll Rw is changed so as to gradually decrease as the time t elapses from the start of winding of the web W, and the winding of the web W on the winding roll Rw is changed. In the final stage of taking, when the winding diameter D becomes larger than a predetermined value, it is changed so as to gradually increase.

Further, as described above, the web winding device 1 includes two touch rolls 50 and 50 in accordance with the two winding rolls Rw and Rw formed on one winding shaft 40, In order to control the pressing force F of the touch roll 50 against the take-up roll Rw, two motors 52 and 52 are electrically connected to the control device 60 (see FIG. 1).
Accordingly, when one winding roll Rw is removed with a winding diameter D smaller than the final winding diameter D of the other winding roll Rw, and a new winding roll Rw is produced, that is, Even when there is a difference between the winding diameter D of one winding roll Rw and the winding diameter D of the other winding roll Rw, the pressing force F of each touch roll 50 against the winding roll Rw is independent. Can be controlled.
Specifically, as shown in FIG. 6, the pressing force F of the touch roll 50 on one winding roll Rw is gradually decreased from the initial value every time t, and the winding roll Rw is removed. Later, when the winding core Cw is attached and a new winding roll Rw is produced, it is possible to control to gradually decrease from the initial value again.
Therefore, according to the winding diameter D of the winding roll Rw to be produced, the plurality of web winding devices are not operated, and the final winding is performed on one winding shaft 40 in one web winding device 1. Two winding rolls Rw and Rw having different winding diameters D can be produced simultaneously. Further, even when two winding rolls Rw and Rw having different final winding diameters D are produced at the same time, the pressing force F is controlled so that the winding tension Tw as shown in FIG. 4 is obtained. Therefore, the web W can be wound up well.

  In addition, although the web winding apparatus 1 in this embodiment divided | segmented the web W into two with the slitter 30, it was set as the structure which provides the two touch rolls 50 according to the division | segmentation number of the web W, ie, the number of winding roll Rw. The number of divisions of the web W and the number of touch rolls 50 are not limited.

DESCRIPTION OF SYMBOLS 1 Web winding device 10 Unwinding shaft 20 Guide roll 30 Slitter 40 Winding shaft 50 Touch roll 51 Arm 52 Motor 60 Control device W Web Ro Unwinding roll Rw Winding roll

Claims (2)

A web winder that winds the web unwound from an unwinding roll formed by winding a web,
An unwinding shaft for attaching the unwinding roll;
A slitter that divides the web unwound from the unwinding roll into a plurality of strips by rotating the unwinding shaft;
By winding the web divided into a plurality of strips by the slitter, a winding shaft in which a plurality of winding rolls are formed along the axial direction on the outer peripheral surface;
A plurality of rolls that contact the outer peripheral surfaces of the plurality of winding rolls and apply a predetermined pressing force to the winding rolls, thereby applying a tension corresponding to the pressing force to the webs of the winding rolls. With a touch roll,
Each of the touch rolls gradually decreases in web tension in the winding roll as the outer diameter of the winding roll in contact increases from the beginning of winding of the web. The web winding device is characterized by changing the pressing force so that the tension of the web in the winding roll gradually increases when is larger than a predetermined value.   2. The web winding device according to claim 1, wherein the outer diameter of each winding roll is calculated based on an angle at which the touch roll contacting the winding roll swings with the change. 3. .

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