JP2008265966A - Tension controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet tension controller capable of retaining the winding tension of the sheet to a constant degree by relaxing/absorbing fine tension variation even when the delay of a mechanical response time occurs and fine tension variation is caused by execution of rotation control of a sheet winding motor for rotating a winding roll based on the position variation of a dancer roller. <P>SOLUTION: The position of the dancer roller 6 is detected through a position detector 8 at pressurization of the sheet 4, and rotation of the sheet winding motor 10 is controlled based on the position variation amount from the position detector 8 through a winding motor controller 9, thereby, tension of the sheet is basically controlled between a sheet feeding out roll 2 and a sheet winding roll 3. Further, at the same time as this, rotation control of a unit movement motor 15 is performed a unit movement motor controller 14 so as to correspond to tension difference of a tension value detected through a tension detector 12 arranged in a downstream side of the dancer roller 6 and a target tension value. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sheet tension control device for controlling the tension of a sheet between a sheet delivery roll and a sheet take-up roll when winding a sheet delivered from a sheet delivery roll onto a sheet take-up roll. Further, the present invention relates to a sheet tension control apparatus that enables a sheet to be wound smoothly by keeping the sheet winding tension constant even when winding a sheet having a thickness of about several μm.

  Conventionally, various tension control devices that maintain a constant sheet tension when winding a sheet have been proposed in order to stably wind a relatively thin sheet.

  For example, Japanese Patent Publication No. 2-34855 discloses a winding tension control device. In the winding tension control device, as shown in FIG. 2, a guide disposed on the downstream side of the dancer roller. The roller is also used as a tension detection roller, and the tension of the traveling sheet is measured by the tension detection device based on the floating amount, and the detection signal measured by the tension detection device is sent to the control device.

Then, the fluid pressure cylinder is driven via the control device and the driving fluid pressure circuit, and the floating amount of the dancer roller generated corresponding to the driving of the fluid pressure cylinder is detected by the floating detection device. When such a detection signal is sent to the winding speed control device, the winding speed control device calculates the rotational speed of the sheet winding shaft necessary to return the dancer roller to the fixed position. A command is issued to the winding motor based on the rotational speed of the shaft. As a result, the sheet is wound around the winding shaft while keeping the tension constant.
Japanese Patent Publication No. 2-34855 (second page, third page, FIG. 2)

  However, in the winding tension control device described in Patent Document 1, the tension of the traveling sheet is measured via a tension detection roller that is also used as a guide roller, and the control device is used based on the measured tension. After the fluid pressure cylinder is driven, the floating amount of the dancer roller is detected by the floating detector. In such a case, the rotational speed of the winding shaft is controlled after detecting the floating amount of the dancer roller. There will be a delay in the mechanical response time until this occurs.

  As described above, when a mechanical response time is delayed from when the floating amount of the dancer roller is detected until the rotational speed of the winding shaft is controlled, when winding a sheet having a thickness of about several μm, It becomes difficult to control fine tension changes. As a result, there is a problem in that the sheet cannot be smoothly wound while the fine winding tension of the sheet generated during winding is kept constant.

  The present invention has been made to solve the above-described conventional problems. When a sheet having a thickness of about several μm is taken up, the sheet is pressed by the dancer roller, and the change in position of the dancer roller is detected. Even when a slight change in tension occurs due to a delay in the mechanical response time due to the rotation control of the sheet take-up motor that rotates the take-up roll based on the position change of the dancer roller. It is an object of the present invention to provide a sheet tension control device that enables a sheet to be wound smoothly by relaxing and absorbing fine tension changes to keep the sheet winding tension constant.

  In order to achieve the above object, a sheet tension control device according to claim 1 includes a sheet delivery roll, a sheet take-up roll for taking up a sheet fed from the sheet delivery roll, and a sheet winding for rotationally driving the take-up roll. A take-off motor, a dancer roller that is disposed between the sheet feeding roll and the sheet take-up roll, presses the sheet, position detection means that detects the position of the dancer roller when the sheet is pressed, and the position detection means In a sheet tension control device comprising a first rotation control means for controlling the rotation of the sheet winding motor based on a position detection signal from the sheet, a sheet travel path formed between the sheet feeding roll and the sheet winding roll A sheet take-up roll is supported by a take-up roll support mechanism that movably supports the sheet take-up roll and the take-up roll support mechanism. A take-up roll moving motor that moves along the travel path, a sheet tension detecting means that is disposed downstream of the dancer roller and detects the tension of the sheet, and a tension detection detected via the sheet tension detecting means And a second rotation control means for controlling the rotation of the take-up roll moving motor based on the signal.

  In the sheet tension control device according to the first aspect, the position of the dancer roller is detected when the sheet is pressed through the position detection unit, and the sheet winding is performed based on the position detection signal from the position detection unit through the first rotation control unit. By controlling the rotation of the take-up motor, the tension of the sheet is basically controlled between the sheet feeding roll and the sheet take-up roll, and at the same time, it is detected via the sheet tension detecting means arranged on the downstream side of the dancer roller. Based on the tension detection signal, the rotation of the take-up roll moving motor is controlled by the second rotation control means, and the rotation of the sheet take-up motor is controlled after detecting the position of the dancer roller. The fine tension change caused by the delay in response time can be relaxed and absorbed and finely adjusted. As a result, the sheet winding tension can be kept constant and the sheet can be wound smoothly.

  Hereinafter, a sheet tension control device according to the present invention will be described based on an embodiment of the present invention with reference to the drawings. FIG. 1 is a control block diagram of the main part of the sheet tension control apparatus according to the present embodiment.

In FIG. 1, a sheet tension control device 1 basically includes a sheet delivery roll 2 and a sheet take-up roll 3, and a film sheet (thickness: 25 to 300 μm, width: 500 to 900 nm, PET (polyethylene). A plastic film such as phthalate), PP (polypropylene), PE (polyethylene), TAC (cellulose triacetate), etc. (hereinafter referred to as “sheet”) 4 is conveyed from left to right in FIG. The sheet winding roll 3 is rotatably supported by the winding unit U. The configuration of the winding unit U will be described later.
A pair of support rollers 5 and 5 are disposed on the downstream side of the sheet delivery roll 2, and a dancer roller 6 is provided between the support rollers 5 so as to be movable in the vertical direction. The dancer roller 6 is in contact with the upper surface of the sheet 4 and presses downward. When the dancer roller 6 moves upward, the pressure applied to the sheet 4 decreases, and the tension of the sheet 4 decreases accordingly. Further, when the dancer roller 6 moves downward, the pressure applied to the sheet 4 increases, and the tension of the sheet increases accordingly.

The dancer roller 6 is moved in the vertical direction by a pressure controller 7 provided with a moving mechanism. Here, the target tension value (N) of the sheet 4 is set in the pressure controller 7 when the sheet tension control device 1 is in operation, and the pressure controller 7 sets the set target tension value to the pressure applied to the dancer roller 6. In conversion, pressure is applied to the dancer roller 6. As the sheet 4 is wound on the sheet winding roll 3, the winding diameter changes. The pressure controller 7 is applied to the dancer roller 6 in response to the change in the winding diameter of the sheet 4. The pressure is changed at a predetermined rate.
Here, as a moving mechanism of the dancer roller 6 attached to the pressure controller 7, in general, one end of a support member that can be swung up and down around the rotation shaft is fixed to the support shaft of the dancer roller 6, and other support members. A mechanism is adopted in which the end is fixed to the end of a cylinder shaft attached to the cylinder, the cylinder shaft is moved up and down to swing the support member around the rotation shaft, and thereby the dancer roller 6 is moved up and down. Yes. When such a mechanism is employed, a multi-phase rotating machine (JISC4906) or a potentiometer is attached to the rotating shaft, and the rotation angle of the rotating shaft is detected via the multi-phase rotating machine or the potentiometer. There is a correlation between the rotation angle of the rotation shaft detected in this way and the pressure applied to the dancer roller 6, and therefore the rotation angle of the rotation shaft is detected according to the swing of the cylinder shaft. When a predetermined rotation angle is detected, a pressure corresponding to the rotation angle is applied to the dancer roller 6, thereby giving a target tension value to the sheet 4.

  The dancer roller 6 is connected to a position detector 8 that detects a position change amount (mm) from the reference position that is generated in the dancer roller 6 when pressure is applied via the pressure controller 7. The position change amount of the dancer roller 6 detected by the position detector 8 is output to the winding motor controller 9.

In the take-up motor controller 9, the relationship between the position change amount of the dancer roller 6 and the rotational speed of the sheet take-up motor 10 necessary to return the dancer roller 6 to the reference position is tabulated and stored in advance. When the detection signal indicating the amount of change in the position of the dancer roller 6 is output from the position detector 8, the take-up motor controller 9 refers to the table and determines the rotation speed of the sheet take-up motor 10 corresponding to the position change. While reading, the rotation control of the sheet winding motor 10 is performed based on the rotation speed.
Based on the rotational drive of the sheet winding motor 10 as described above, the roll shaft 11 of the sheet winding roll 3 is rotated and the sheet 4 is wound around the sheet winding roll 3.

  A tension detector 12 that contacts the back surface of the sheet 4 and detects the tension of the sheet 4 is disposed on the downstream side of the dancer roller 6. The tension value of the sheet 4 detected via the tension detector 12 is output to the tension controller 13. Here, the target tension value (N) of the sheet 4 is set in the tension controller 13 during operation of the sheet tension control device 1, and the tension controller 13 detects the tension value of the sheet 2 detected via the tension detector 12. And the difference between the preset target tension value.

  The difference between the tension values calculated by the tension controller 13 is output to the unit moving motor controller 14. Here, the unit movement motor controller 14 includes a unit movement motor necessary for eliminating the difference between the tension values output from the tension controller 13 and the tension value so that the tension of the seat 4 becomes the target tension value. The relationship with the rotational speed of 15 is tabulated and stored in advance. When the signal indicating the difference between the tension value of the sheet 4 detected via the tension detector 12 and the target tension value is output from the tension controller 13, the unit moving motor controller 14 refers to the table and determines the tension difference. The rotation speed of the unit movement motor 15 corresponding to the above is read out, and the rotation control of the unit movement motor 15 is performed based on the rotation speed.

  Here, the configuration of the winding unit U that rotatably supports the sheet winding roll 3 will be described. The winding unit U includes a pair of support plates 16 (only one support plate 16 is shown in FIG. 1), and the lower ends of both support plates 16 are connected via a base portion 19. The roll shaft 11 of the sheet take-up roll 3 is supported by support holes 18 formed in both support plates 16.

  In addition, the winding unit U is placed below the base portion 19, and the winding unit U is disposed along a sheet traveling path formed between the sheet feeding roll 2 and the sheet winding roll 3. A winding unit support mechanism S that is movably supported (along the horizontal direction in FIG. 1) is disposed.

Such a winding unit support mechanism will be described with reference to FIG. FIG. 2 is a schematic perspective view of the winding unit support mechanism.
In FIG. 2, the winding unit support mechanism S is connected to the slider 21 on which the base portion 19 is mounted, the rail 21 that supports the slider 20 so as to be movable, and the rotating shaft of the unit moving motor 15, and the rail 21. An internal ball screw (not shown) and a meshing member (not shown) fixed to the slider 20 and meshing with a thread groove of the ball screw are configured. In such a configuration, when the unit moving motor 15 is rotated, the ball screw connected to the rotation shaft is rotated, and the meshing member of the slider 20 is sent through the screw groove of the ball screw based on the rotation of the ball screw. The slider 20 is reciprocated in the direction of the arrow. In addition, about the winding unit support mechanism S, conventionally well-known various structures are employable.

  An operation performed in the sheet tension control apparatus 1 configured as described above will be described. First, the front end of the sheet 4 is fixed to the sheet take-up roll 3 and stretched in the state shown in FIG. Subsequently, a target tension value is set in the pressure controller 7 and a target tension value is set in the tension controller 13.

Thereafter, when the tension control device 1 is operated, the pressure controller 7 converts the set target tension value into a pressure applied to the dancer roller 6 and applies pressure to the dancer roller 6. Further, the position detector 8 detects the position change amount of the dancer roller 6 from the reference position, and outputs the detected position change amount to the take-up motor controller 9.
When a detection signal indicating the position change amount of the dancer roller 6 is output from the position detector 8, the take-up motor controller 9 reads the rotation speed of the sheet take-up motor 10 corresponding to the position change amount with reference to the table. At the same time, rotation control of the sheet take-up motor 10 is performed based on the rotation speed.

  Thus, based on the fact that the sheet take-up motor 10 is driven to rotate, the roll shaft 11 of the sheet take-up roll 3 is rotated, and the sheet 4 is taken up by the sheet take-up roll 3, Since the rotational speed of the sheet take-up motor 10 is controlled in accordance with the position change amount of the dancer roller 6, the tension of the sheet 4 is basically kept at a substantially constant value.

  Simultaneously with the above-described operation, the tension of the sheet 4 is detected via the tension detector 12, and the detected tension value of the sheet 4 is output to the tension controller 13. Further, the tension controller 13 calculates the difference between the tension value of the sheet 2 detected via the tension detector 12 and a preset target tension value, and the calculated difference between the tension values is: It is output to the unit moving motor controller 14. Further, in the unit moving motor controller 14, the difference between the tension value output from the tension controller 13 and the unit moving motor 15 necessary for eliminating the difference between the tension values and setting the tension of the seat 4 to the target tension value. Based on the table storing the relationship with the rotation speed, the rotation speed of the unit movement motor 15 corresponding to the tension difference is read, and the rotation control of the unit movement motor 15 is performed based on the rotation speed.

When the unit movement motor 15 is rotationally driven in this way, the winding unit U is finely controlled in the arrow direction in the winding unit support mechanism 19 in accordance with the rotation direction. Based on the fine movement control of the winding unit U, the tension of the sheet 4 is corrected so that the tension value detected via the tension detector 12 becomes the target tension value set in the tension controller 13.

  As described above, according to the tension control device 1 according to the present embodiment, the position of the dancer roller 6 is detected when the sheet 4 is pressed via the position detector 8, and the position is detected via the winding motor controller 9. By controlling the rotation of the sheet take-up motor 10 based on the position change amount from the container 8, the sheet tension between the sheet feed roll 2 and the sheet take-up roll 3 can be basically controlled to be substantially constant, At the same time, in response to the tension difference between the tension value detected via the tension detector 12 arranged on the downstream side of the dancer roller 6 and the target tension value, the unit movement motor controller 14 causes the unit movement motor 15 to By performing the rotation control, the rotation of the sheet winding motor 10 is detected after the position of the dancer roller 6 is detected, resulting in a delay in mechanical response time. It is possible to finely adjust relaxed absorbing fine tension change that. As a result, the sheet winding tension can be kept constant and the sheet can be wound smoothly.

  In addition, this invention is not limited to the said embodiment, Of course, a various change and improvement are possible within the range which does not change the summary of this invention.

It is a control block diagram of the principal part of the sheet tension control device concerning this embodiment. It is a schematic perspective view of a winding unit support mechanism.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tension control apparatus 2 Sheet delivery roll 3 Sheet winding roll 4 Sheet 5 Support roller 6 Dancer roller 7 Pressure controller 8 Position detector 9 Winding motor controller 10 Sheet winding motor 11 Roll shaft 12 Tension detector 13 Tension controller 14 Unit movement Motor controller 15 Unit moving motor S Winding unit support mechanism

Claims (1)

A sheet delivery roll;
A sheet take-up roll for taking up the sheet sent from the sheet feed roll;
A sheet winding motor that rotationally drives the winding roll;
A dancer roller disposed between the sheet delivery roll and the sheet take-up roll to pressurize the sheet;
Position detecting means for detecting the position of the dancer roller when the sheet is pressed;
A sheet tension control device comprising: a first rotation control unit that controls rotation of the sheet winding motor based on a position detection signal from the position detection unit;
A winding roll support mechanism that movably supports the sheet winding roll along a sheet traveling path formed between the sheet feeding roll and the sheet winding roll;
In the winding roll support mechanism, a winding roll moving motor that moves the sheet winding roll along the sheet traveling path;
A sheet tension detecting means disposed on the downstream side of the dancer roller for detecting the tension of the sheet;
A sheet tension control device comprising: second rotation control means for controlling rotation of the take-up roll moving motor based on a tension detection signal detected through the sheet tension detection means.

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