JPH0930698A - Tension control method for tapeless splicing - Google Patents

Abstract

(57) Abstract: In a winding device, during tapeless splicing in which core switching is performed without using an adhesive tape, excessive slack and tension of the running web are prevented. SOLUTION: While the web 1 is wound on the old winding core 4a of the old shaft 5a, the running web 1 is moved and guided by a guide roll 4.
In the tapeless splicing operation of moving the new winding core 4b so as to hold the new winding core by 5, and cutting the web downstream of the new winding core to wind the end of the web around the new winding core.
The moving guide roll 45 lifts the web 1 to lift the new winding core 4
Until a certain point of contact with b, the rotation control of the old shaft 5a is performed by the tension detection means 71 upstream of the winding device 2, and thereafter, the old shaft 5a is provided between the new shaft and the old shaft. The auxiliary tension control by the signal from the auxiliary tension detecting means 72 and the tension control by the tension detecting means 71 for the new shaft 5b prevent excessive slack and tension of the running web.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a winding device in a device for handling a web such as a film or a paper such as a printing machine, a coater or the like, and a web being wound on a new core onto a new core. The present invention relates to a web tension control method when switching (splicing).

[0002]

2. Description of the Related Art Conventionally, in a turret type winding device, a turret is wound on a winding core (hereinafter referred to as an old winding core) held by one winding shaft (hereinafter referred to as an old winding shaft) provided on the turret. To wind and switch the web on the new winding core set on the other winding shaft (hereinafter referred to as the new shaft), attach an adhesive tape to the outer peripheral surface of the new winding core in advance,
While winding the web on the old core, rotate the turret to bring the web running toward the old core closer to the new core and press the web onto the adhesive tape on the new core to bond it. A splicing method has been performed in which the web is cut along with the old winding core and the web is wound around the outer circumference of the new winding core.

By the way, as a tension control method in the conventional winding device, a signal from a tension detecting means (dancer roll, tension pickup roll, etc.) of the web arranged upstream of the winding device is passed to the control unit.
The control unit issues a speed command to the drive motor for the old shaft that is winding the web, and controls the winding shaft speed.
A method called "tension control" is often used. In the winding device performing such tension control, at the time of the above-mentioned splicing, the new shaft is controlled to have the same speed as the running web while the old shaft is under tension control as in the normal winding. It was driven (hereinafter this drive is called pre-drive), the web was wound around the new shaft in that state, and then the new shaft was immediately switched to tension control.

[0004]

However, the conventional splicing method has a problem that it is necessary to attach an adhesive tape to the outer peripheral surface of the new winding core, which is a troublesome work.
Therefore, there is a demand for a tapeless splicing method in which the cores are switched without using such an adhesive tape.
As a result of the study, the present inventors also developed the following tapeless splicing method. That is, while winding the web on the winding core held by one winding shaft (old shaft) provided on the turret of the winding device, the turret is swung to run toward the winding core. The running path of the running web to the vicinity of the new winding core set on the other winding shaft (new shaft) provided on the turret, and then the running web is moved by the moving guide roll to the new winding. In this method, the core is moved so as to embrace it, then the web is cut downstream of the new winding core, and the web end is wound around the new winding core to switch the core. Here, before the web is cut, since the new winding core is held by the moving guide roll, it is possible to satisfactorily wind the front end of the web around the new winding core without using an adhesive tape. .

However, when the tapeless splicing method is carried out, it has been found that there is a problem in tension control. That is, in carrying out the above-mentioned tapeless splicing method, as in the tension control in the conventional splicing method using an adhesive tape, while the old shaft is being tension-controlled in the same manner as during normal winding, the new shaft is traveling. Pre-driving at the same speed as the web, move the web in that state with the guide roll to move so as to hold the new winding core, then cut the web downstream of the new winding core, and cut the web end. After winding around a new winding core, when performing tension control that switches the new shaft to tension control,
Although the web is wound on the old winding core, but after the web is wound around the new winding core at a certain winding angle or more, the web is tension-cut by the new winding core. Even if the rotation speed of the old shaft is changed according to the signal indicating the change in tension, the influence does not reach the web at the position where the tension detecting means is arranged, and therefore the tension control at this position cannot be performed. There was slack or tension on the web. Moreover, in the winding device, even if the rotation speed of the old shaft is slightly changed, the tension of the web between the new winding core and the old winding core is greatly changed. There is also a problem in that the web between the old winding core and the web undergoes severe tension fluctuations, which often causes extreme slackness and tension, causing the web to break.

The present invention has been made in view of the above problems, and at the time of tapeless splicing, the web upstream of the winding device and the web inside the winding device (web between the new shaft and the old shaft). It is an object of the present invention to provide a tension control method at the time of tapeless splicing capable of controlling the tension so as not to cause an excessive tension fluctuation.

[0007]

In order to achieve the above-mentioned object, the tension control method of the present invention controls the rotation of the old shaft during the tapeless splicing operation during the normal winding operation before the start of the splicing operation. The tension control is performed according to a signal from the tension detecting means of the web arranged upstream of the take-up device, the tension control is continued even after the splicing operation is started, and the predetermined timing after the web comes into contact with the new winding core. Then, in accordance with a signal from the auxiliary tension detecting means arranged to detect the web tension between the new shaft and the old shaft, the auxiliary shaft is switched to the auxiliary tension control for controlling the rotation of the old shaft. The rotation control is performed by increasing the web traveling speed by the time the moving guide roll comes into contact with the web, and from that time, the rotation control of the old shaft is switched to the auxiliary tension control. Until changing, in which a structure that switches the tension control for controlling in response to a signal from the tension detecting means are arranged in the winding device upstream.

According to the present invention having the above-mentioned structure, the tension control is performed on the old shaft by the signal from the tension detecting means upstream of the winding device when the web running toward the old shaft is not in contact with the new winding core. Since the web contacts the new winding core at a certain winding angle, the auxiliary tension control is performed on the old shaft by the signal from the auxiliary tension detecting means provided in the winding device. The web is always wound on the old shaft with a good winding tension, and the tension between the new shaft and the old shaft is not excessively changed. In addition, the new shaft is in a state in which the tension control is performed by the signal from the tension detecting means upstream of the winding device before the old shaft shifts to the auxiliary tension control. The web tension at the position where the upstream tension detecting means is provided is controlled by the old shaft or the new shaft, and a large tension fluctuation does not occur in the web at this position. Thus, the web does not undergo large tension fluctuations, and therefore, excessive slack and tension of the web do not occur, and the tapeless splicing can be performed without breaking the web.

Here, from the time when the tension control of the new shaft is started to the time when the web is cut and wound around the new winding core, the gain of the tension control for the old shaft and the new shaft is lower than that during the normal winding. It is preferable to set.
With this configuration, the responsiveness of the rotational speed changes of the new shaft and the old shaft to the change in the tension of the web becomes low, and therefore, the change in the tension caused on the web when the moving guide roll changes the running position of the web is not affected. There is not much response, and therefore hunting can be prevented from occurring.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below. First, an example of a device for performing tapeless splicing will be described. 1 to 3 are schematic cross-sectional views showing a web winder of a printing machine provided with a tapeless splicer in different operating states, wherein 1 is a web and 2 is a turret type winder for winding the web 1. The device is a turret 3 which is rotatable around a fulcrum O, winding shafts 5a and 5b which are respectively held at both ends thereof and which rotate while holding winding cores 4a and 4b such as paper tubes, and both winding shafts. It is provided with guide rolls 6a, 6b and the like arranged on both sides of the intermediate position of 5a, 5b. The turret 3 has a pair of touch roll arms 34a, 3 which can be swiveled around fulcrums O ₄ , O ₅ , respectively.
4b and air cylinders 35a, 35b for rotating the same
And each touch roll arm 34a,
Touch rolls 36a and 36b are attached to the tip of 34b at positions where they come into contact with the cores 4a and 4b. Since the drawing shows the state in which the web 1 is wound around the winding core 4a, the winding core 4a and the winding shaft 5a will be referred to as the old winding core 4a and the old shaft 5a, respectively, and the winding core 4b and the winding shaft 4a will be described below. Axis 5b
And a new winding core 4b and a new shaft 5b, respectively.

Reference numeral 7 is a feed frame located near the winding device 2, 8 is a guide roll attached to the feed frame 7, and 38 is attached to the feed frame 7 near the winding position P _1. Further, 39 is a guide roll held by the support 38, and 40 is a tapeless splicer (hereinafter referred to as a splicing device). The splice device 40 is provided below the web traveling path defined by the guide rolls 39, that is, the old winding core 4
It is located on the winding side of the web relative to a.

The splicing device 40 includes a splicing arm 43 pivotably provided on the supporting base 38 about a fulcrum O ₆ , and a retracted position where the splicing arm 43 does not interfere with the web winding by the winding device 2 (see FIG. 1) and a splice position for switching the web from the old winding core 4a to the new winding core 4b (the position shown in FIG. 3). As the first drive device 44, any one such as a cylinder mechanism such as hydraulic pressure or pneumatic pressure, a motor, etc. can be used, but it is preferable to use a hydraulic cylinder so that the splice arm 43 can move smoothly.

At the tip of the splice arm 43,
When the splice arm 43 pivots to the splice position,
The web 1 running toward the old core 4a is fed to the new core 4
A moving guide roll 45 for guiding so as to contact with b is attached, and when the splice arm 43 pivots to the splice position on the side closer to the fulcrum than the moving guide roll 45, it faces the old winding core 4a. An auxiliary roll 47 is provided which presses the moving web 1 against the new winding core 4b and nips it. As can be seen from FIG. 4, the auxiliary roll 47 is held by an auxiliary arm 49 which is rotatable with respect to the splice arm 43 and is driven by a cylinder mechanism 50 such as an air cylinder. Thus, by operating the cylinder mechanism 50, the auxiliary roll 47 can be pressed against the new winding core 4b or separated from the new winding core 4b. The auxiliary roll 47 is attached at a position slightly upstream of the position where the web 1 that passes through the outer circumference of the new winding core 4b and reaches the moving guide roll 45 leaves the new winding core 4b so that the web 1 is nipped to the new winding core 4b. Stipulated in.

The splice arm 43 is further provided with a cutting device 53 for cutting the web 1 running between the auxiliary roll 47 and the movement guide roll 45.
This cutting device 53 is a knife 53a for cutting the web 1.
And the moving block 53b holding the
It is equipped with an air cylinder 53c that reciprocates 3b,
Further, the moving block 53b is provided with an air nozzle 54 for blowing air to the web 1 upstream of the cutting position by the knife 53a.

In FIG. 1, the splicing device 40 is further below the web runway and on the splice arm 43.
And a nip roll arm 56 provided so as to be rotatable around the same fulcrum O ₆ as
The retracted position (the position shown in FIG. 1) that does not interfere with the winding of the web by the winding device 2 and the web from the old winding core 4a to the new winding core 4a.
A second drive device (not shown) for reciprocating a splice position (position shown in FIG. 3) for switching to b is provided.
This second drive unit also has a cylinder mechanism such as hydraulic pressure and pneumatic pressure.
Although any motor or the like can be used, as described later, the nip roll arm 56 is replaced by the splice arm 4
In this case, it is preferable to use an air cylinder so as not to interfere with the rotation of the nip roll arm 56.

The nip roll arm 56 is provided with a nip roll 57 that nips the web 1 running toward the old winding core 4a so as to hold the web 1 running toward the old winding core 4a when the nip roll arm 56 is rotated to the splice position. Has been. As can be seen from FIG. 4, this nip roll 5
7 is configured to be held by an auxiliary arm 58 that is rotatable with respect to the nip roll arm 56 and driven by a cylinder mechanism 59 such as an air cylinder. Thus, by operating the cylinder mechanism 59, the nip roll 57
Can be pressed against the new winding core 4b or separated from the new winding core 4b. The mounting position of the nip roll 57 is such that the web 1 is nipped on the new winding core 4b upstream of the auxiliary roll 47, and the web 1 can be wound around the new winding core 4b at a winding angle as large as possible. In this example, the winding angle is set to 180 ° or more. The use of such a large wrapping angle has the advantage that the operation of winding the web 1 around the new winding core 4b becomes reliable.

The splice arm 43 is provided with a stopper 61 for restricting the position of the nip roll arm 56 with respect to the splice arm 43 in the direction toward the standby position. Therefore, as shown in FIGS. 1 and 2, when the splice arm 43 is swung toward the splice position with the nip roll arm 56 abutting the stopper 61, the nip roll arm 56 is swung by the second drive device. Even without it, it can be swiveled with the splice arm 43 towards the splice position.

Next, the tapeless splicing operation by the splicing device 40 having the above construction will be described with reference to FIGS. In the following description, steps a to m correspond to (a) to (m) in FIGS. 5 and 6, respectively. During normal winding, as shown in FIG. 1, the web 1 is wound on the old winding core 4a located at the winding position P ₁ .
The touch roll 36a is pressed on it. In addition, the splice arm 43 and the nip roll arm 56
Is a standby position that does not interfere with web winding.

When the winding amount of the web on the old winding core 4a becomes large and the switching becomes necessary, the turret 3 rotates counterclockwise, and the old winding core 4a being wound on the web is moved downward. That is, the splice device 40 is passed and moved to the core replacement position P ₂ . As a result, as shown in FIG. 2, the web 1 is guided by the guide rolls 6a located below to run, and the new winding core 4b moved to the winding position P ₁ is located above it. Becomes At this time, the new winding core 4b
The corresponding touch roll 36b is a new winding core 4b.
Waiting at a position away from. The state at this time is shown in FIG.
This is the state of step a shown in (a).

Next, the first drive device 4 connected to the splice arm 43 in a state where the new winding core 4b is rotationally driven.
4 pivots splice arm 43 upwards. This causes the splice arm 43 to pivot upward and the nip roll arm 56 to pivot upward as well. During this ascent, first, the moving guide roll 45 comes into contact with the web 1 (step b), and the web 1 is raised to move the new winding core 4
b (step c), then nip roll 5
7 contacts the web 1 (step d), and the splice arm 43 moves up to the splice position and stops (step e). After that, the auxiliary roll 47 and the nip roll 57 press the web 1 against the new winding core 4b and nip it (step f). Note that this state is the state shown in FIG.

Next, the cutting device 53 is activated and the knife 53 is
a moves forward to cut the running web 1, and at the same time, the air nozzle 54 blows air onto the web 1. As a result, the cut end of the web 1 is wound around the new winding core 4b and spliced (step g). afterwards,
The auxiliary roll 47 separates from the new winding core 4b (step h),
The splice arm 43 pivots downward (step i),
Next, the touch roll 36b is pressed against the new winding core 4b to hold down the wound web 1 (step j), then the nip roll 57 separates from the new winding core 4b (step k), and the nip roll arm 56 moves downward. Turn (step l) and return to the original standby position. With the above, the core switching operation is completed (step m). After the switching operation is completed, the old winding core 4a on which the web is wound at the winding core replacement position P ₂ is removed at an appropriate time, and an empty winding core is set to prepare for the next operation.

Next, the tension control during the tapeless splicing operation will be described. FIG. 7 is a block diagram showing a tension control system during normal winding, and FIG. 8 is a block diagram showing a tension control system during splicing. In FIG. 7 and FIG. 8, 70a and 70b are winding devices 2.
A drive motor 71, which is drivingly connected to the old shaft 5a and the new shaft 5b, is a tension detecting means provided to detect the tension of the web 1 upstream of the winding device 2. In this embodiment, the dancer roll is used. Is shown. 72
Is an auxiliary tension detecting means arranged to detect the web tension between the new shaft 5b and the old shaft 5a in the winding device 2, and a tension pickup is used in this embodiment. In the present embodiment, this auxiliary tension detecting means 72 is held by an air cylinder 73 arranged below the turret 3 as shown in FIGS. 1 to 3, and does not interfere with the turret 3 when turning. As described above, the turret 3 comes up and contacts the web 1 after the turret 3 has finished turning, and the tension can be detected.
In FIGS. 7 and 8, 75 is the drive motor 7 of the winding device 2.
0a, 70b is a tension control unit for controlling the operation of the drive motors 70a, 70b on the basis of signals from the tension detecting means 71 and the auxiliary tension detecting means 72, as will be described later. It has a control function, a function of pre-driving the drive motors 70a and 70b, and a function of switching these drive systems at desired timing.

FIG. 9 is a timing chart showing the tension control method according to the embodiment of the present invention.
To g correspond to steps a to g shown in FIGS.
First, during normal winding before the splicing operation, as shown in FIG. 7, a signal from the tension detecting means 71 is sent to the tension control unit 75, and the tension control unit 75 causes the web tension to reach a desired value. As described above, a speed command is issued to the drive motor 70a for the old shaft during winding of the web to control the speed of the winding shaft. That is, the old shaft 5a is under tension control.

Next, after rotating the turret 3 of the winding device 2 and moving the auxiliary tension detecting means 72 to a position for detecting the web tension between the old and new shafts, first of all, at the start of the splicing operation, the new shaft is first. A pre-drive operation is performed on the drive motor 70b for driving 5b, and the peripheral speed of the new winding core 4b held on the new shaft 5b is made to match the traveling speed of the web 1. And, in the state where the old shaft 5a is under tension control,
The splicing operation is started, the web 1 is moved by the moving and moving guide roll 45, and the new winding core 4b is brought into contact so as to be held. Then, at a predetermined timing after the web 1 contacts the new winding core 4b (step c), the old shaft 5a
Is switched to the auxiliary tension control for performing speed control based on the signal from the auxiliary tension detecting means 72. The timing at this time is determined so as to be when the web 1 is wound around the new winding core 4b at a wrapping angle such that the web 1 does not substantially slip, and is determined according to the physical properties of the web, the operating speed, and the like. It may be set appropriately. As a result, the web 1 becomes the old winding core 4a.
Although it is in the state of being wound around, the old shaft 5a runs between the new winding core 4b and the old winding core 4a when the tension is cut by the new winding core 4b on the upstream side. The tension acting on the web 1 is controlled to be a predetermined value. Therefore, the web 1 running between the new winding core 4b and the old winding core 4a is not excessively changed in tension, and therefore the tension or slack is hardly generated, and the web 1 is attached to the old shaft 5a. Continue to be wound up well.

On the other hand, on the side of the new shaft 5b, when the old shaft 5a is switched to the auxiliary tension control, its drive motor 7 is driven.
0b is shifted to control by a speed command based on a signal from the tension detecting means 71, that is, tension control. Thus, when the old shaft 5a is switched to the auxiliary tension control and the tension control of the web 1 at the tension detecting means 71 arranged upstream of the winding device is not performed, the new shaft 5b is replaced by the new shaft 5b upstream of the winding device. Therefore, the tension of the web 1 is controlled. Therefore, the tension of the web at the tension detecting means 71 is constantly controlled, and the tension of the web 1 in this portion is not excessively changed.

After switching the old shaft 5a to the auxiliary tension control for controlling the web tension between the new and old shafts and switching the new shaft 5b to the tension control for controlling the web tension upstream of the winding device, the splicing operation is performed in that state. Continuing, in step g, after cutting the web 1 around the old winding core 4a and winding the web around the new winding core 4b, the operation of the old shaft 5a is stopped.
On the other hand, the new shaft 5b remains as it is and the tension control is continued.
The normal winding state is entered. By performing the operation control of the old shaft 5a and the new shaft 5b as described above, it is possible to suppress the excessive tension fluctuation of the web 1 and perform the tapeless splicing operation well.

In the above embodiment, the timing at which the new shaft 5b is switched to the tension control is the time when the old shaft 5a is switched to the auxiliary tension control. This configuration has an advantage that control is easy because the control methods of the drive motors 70a and 70b for the old shaft and the new shaft are switched at the same time. However, the present invention is not limited to this configuration, and the timing of transition to the tension control of the new shaft 5b is slightly earlier than in the case shown in FIG. It may be until the time when the shaft 5a is switched to the auxiliary tension control. In that case, the tension of both the old shaft 5a and the new shaft 5b is temporarily controlled, and the tension detecting means 71 is used.
There is an advantage that the tension control of the web 1 at the position where is provided is more stable.

The tension control described above is the basis of the present invention, and it is desirable to make various corrections in implementing this. The correction operation will be described below with reference to FIG.
First, when the moving guide roll 45 comes into contact with the web 1 (step b), the control gain of the tension control by the tension detecting means 71 arranged upstream of the winding device is 50 to 80% of the control gain at the time of normal winding. The new shaft 5b for changing the tension of the web 1 by changing the splicing gain of
Also, the response of the speed command of the old shaft 5a is reduced. This splicing gain continues until step g. The reason for using the splice gain is as follows. That is, after step b, since the moving guide roll 45 changes the traveling position of the web 1, a large tension fluctuation may occur in the upstream web 1, and this tension fluctuation causes the rotation of the new shaft 5b and the old shaft 5a. If the speed responds sensitively, hunting may occur, but if the splice gain with a low response is adopted as described above, it will not respond promptly to tension fluctuations occurring in the web, and therefore hunting will not occur. It can be prevented. Similarly, the old shaft 5a
Even in the case of the auxiliary tension control for, the control gain of the tension control by the auxiliary tension detecting means 72 is set to the splicing gain equivalent to the splicing gain by the tension detecting means 71.

Next, at the time of tension control after step b, paper path correction is performed on the speed command of the new shaft 5b and the old shaft 5a. This paper path correction is a change in the path length of the web 1 due to the rise of the splice arm 43, or
This is done in order to avoid an abnormal increase in tension of the web 1 between the new winding core 4b and the old winding core 4a due to the control not catching up by changing the speed at a constant rate with respect to the change. Performs speed correction so as to increase the speed for the new shaft 5b and decrease the speed for the old shaft 5a. The speed correction amount by this paper path correction may be appropriately set in consideration of the rising speed of the splice arm. The period during which the paper path is corrected is naturally a period during which the path length of the web 1 is changing, and for the new shaft 5b, from the time when the tension control is started to the time when the rise of the splice arm 43 is completed (step e). Up to), until the transition to the auxiliary tension control from step b for the old shaft 5a.

Further, after the old shaft 5a enters the auxiliary tension control, the speed of the new shaft 5b is corrected. This speed correction is 0. The rotation speed of the new shaft 5b is slightly increased by adding a few%. After the old shaft 5a enters the auxiliary tension control, the tension control of the new shaft 5b is performed to control the tension of the web 1 upstream of the winding device 2. At this time, the nip of the web with respect to the new winding core 4b is insufficient. The running speed of the web 1 may be due to the occurrence of
It tends to be slightly slower than the peripheral speed of b. Therefore,
In order to increase the speed of the web 1, the peripheral speed of the new winding core 4b is slightly increased by performing the speed correction described above, and this speed correction allows the tension control of the web 1 at the position where the tension detecting means 71 is arranged to be excellent. Done.

By performing various corrections as described above, the tension control of the web upstream of the winding device and in the winding device (between the new shaft and the old shaft) can be more favorably performed. These correction values are determined by experiments or calculations according to the type of web, the operating speed, the rising speed of the splice arm, etc.
It may be set appropriately.

Although the above embodiment is applied to the tapeless splicer having the structure shown in FIGS. 1 to 4, the tapeless splicer to which the tension control method of the present invention is applied is applied. The support is not limited to the one shown in the drawing, but for example, the moving guide roll 45, the auxiliary roll 47,
Nip roll 57, cutting device 53, auxiliary tension detecting means 7
The present invention can be applied to tapeless splicers having different arrangements such as two and holding mechanisms.

[0033]

As is apparent from the above description, according to the present invention, in the tapeless splicing operation, the web wound around the old winding core does not slip with respect to the new winding core. After contacting up to the winding angle, the old shaft that winds the web is subjected to auxiliary tension control by a signal from the auxiliary tension detecting means provided in the winding device, so that the old shaft and the new shaft are separated. The winding can be continued satisfactorily without excessive tension fluctuation in the web of the new shaft, and the new shaft is tensioned by the signal from the tension detection means upstream of the winding device before the old shaft shifts to the auxiliary tension control. Since the control is performed, the web tension at the position where the tension detecting means is provided upstream of the winding device is controlled by the old shaft or the new shaft during the splicing operation, and the web at this position is controlled. large It without causing power fluctuations, after all, excessive slack and tension does not occur to the web, it has the effect of being able to perform well tapeless splice without causing breakage of the web.

Here, from the time when the tension control of the new shaft is started to the time when the web is cut and wound around the new winding core, the gain of the tension control for the old shaft and the new shaft is lower than that in the normal winding. If set, the responsiveness of changes in the rotational speed of the new and old shafts to changes in the tension of the web will be low, and as a result, the changes in tension generated on the web when the moving guide roll changes the running position of the web will be reduced. Does not respond much, and therefore, the effect of preventing the occurrence of hunting can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a web winding machine of a printing machine including a tapeless splicer.

FIG. 2 is a schematic sectional view showing the device shown in FIG. 1 in a state where a turret is swung.

FIG. 3 is a schematic sectional view showing the device shown in FIG. 1 in a state during a splicing operation.

4 is a schematic cross-sectional view showing a main part of the device shown in FIG.

FIG. 5 is a schematic side view showing steps a to i of the splicing operation by the tapeless splicer.

FIG. 6 is a schematic side view showing steps j to m of the splicing operation by the tapeless splicer.

FIG. 7 is a block diagram showing a tension control system during normal winding in the above embodiment.

FIG. 8 is a block diagram showing a tension control method during a splicing operation in the above embodiment.

FIG. 9 is a timing chart of a tension control method according to an embodiment of the present invention.

[Explanation of symbols]

 1 web 2 winding device 3 turret 4a winding core (old winding core) 4b winding core (new winding core) 5a winding shaft (old shaft) 5b winding shaft (new shaft) 40 tapeless splicer (splicing device) 43 Splice arm 45 Moving guide roll 47 Auxiliary roll 53 Cutting device 57 Nip roll 70a Drive motor (for old shaft) 70b Drive motor (for new shaft) 71 Tension detecting means 72 Auxiliary tension detecting means 73 Air cylinder 75 Tension control unit

Claims (2)

[Claims] 1. The old turret is swung while winding a web on an old winding core held by one winding shaft (hereinafter referred to as an old shaft) provided on a turret of a winding device. The traveling path of the web running toward the winding core is moved to the vicinity of a new winding core set on the other winding shaft (hereinafter referred to as a new shaft) provided on the turret, and then the running web. Is moved by a moving guide roll so as to hold the new winding core, then the web is cut downstream of the new winding core, and the web end is wound around the new winding core to switch the winding core. In operation,
The rotation control of the old shaft is performed by a tension control which is controlled in accordance with a signal from a tension detecting means arranged to detect the web tension upstream of the winding device during a normal winding operation before the start of the splicing operation. , Even after the splicing operation starts,
Continuing the tension control, at a predetermined timing after the web comes into contact with the new winding core, the signal from the auxiliary tension detecting means arranged to detect the web tension between the new shaft and the old shaft is output. In response to this, switching to the auxiliary tension control that controls the rotation of the old shaft, while the rotation control of the new shaft,
By the time the moving guide roll comes into contact with the web, the web traveling speed is increased, and from that time until the rotation control of the old shaft is switched to the auxiliary tension control, the web is placed upstream of the winding device. The tension control method at the time of tapeless splicing is characterized in that the tension control is switched according to a signal from the tension detecting means. 2. The gain of the tension control for the new shaft and the old shaft is lower than that during normal winding from the time when the tension control for the new shaft is started to the time when the web is cut and wound around the new winding core. The tension control method at the time of tapeless splicing according to claim 1, wherein the tension control method is set.