JPH0364416B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field of the Invention] The present invention provides a continuous web splicing method and apparatus;
More specifically, the present invention relates to a method and apparatus for continuous web splicing that applies stable tension to the web and prevents the web from being cut during continuous automatic web splicing of old and new web rolls. [Prior Art] Conventional technologies related to continuous automatic web splicing methods and devices include Japanese Patent Publication No. 56-20255 and Japanese Patent Publication No. 57-2025.
-9928, and those described in Japanese Utility Model Application Publication No. 59-40248 are known. In addition, as a prior art related to a web tension control method and device, there is
The one described in the publication No. 1 is known. [Problems to be Solved by the Invention] However, among the above-mentioned continuous automatic splicing technologies, those that automatically splice webs without reducing the running speed of the webs cannot be used for webs with normal tensile strength (e.g. , cardboard liner, film, gauze)
webs with extremely low tensile strength (e.g. disposable diaper mounts or water-conducting paper)
It is unsuitable for. This is because during automatic splicing, it usually takes a certain amount of time to start up the new web roll, and as a result, a sudden tensile force is applied to the new web roll after automatic splicing, resulting in a decrease in tensile strength. This is because extremely small webs cannot withstand such tensile forces.
Therefore, for webs with extremely low tensile strength, after splicing the web at a low running speed,
The speed was gradually increased again. In addition, the web tension control technology described above cannot control the tension that acts during splicing for webs with extremely low tensile strength. It was gradually rising. Therefore, in these conventional techniques, when joining webs with extremely low tensile strength, the webs are intermittently fed into a processing machine, etc., resulting in loss of working time and loss of processing time due to changes in operating conditions. This sometimes resulted in defective processed products and damage during the processing process. [Means for solving the problem] The present invention maintains the web on the path from the new web roll to the web splicing device in a relaxed state until the speed at which the web is fed out from the new web roll reaches a steady state. By making it possible to pay out
The above-mentioned web absorbs the difference between the running speed of the web in the above-mentioned web splicing device and the running speed of the web in the web roll driving device that feeds out the new web roll, and the speed of feeding out the web from the new web roll reaches a steady state. In this way, the insufficient amount of feed is compensated for, thereby solving the above-mentioned problems in the conventional method that occur when joining webs. That is, the present invention provides a continuous web process comprising a web joining process in which the leading end of a new web roll is joined to a joining part such as the terminal end of an old web roll, and a web unwinding process in which the web is let out from the new web roll. In the splicing method, between the web splicing step and the web unwinding step, the difference between the web running speed in the web splicing step and the web traveling speed in the web unwinding step is absorbed to reduce the amount of web unwinding. A web tension control process that supplements the web tension control process, which comprises a dancer arm that is rotatably provided, a dancer roller that is rotatably attached to one end of the dancer arm, and a dancer roller that is attached to one end of the dancer arm and that is related to the above-mentioned web running speed. A web tension control step is provided, which is controlled by a dancer device having a drive device that is actuated by the input of the detected detection signal to rotate the dancer arm, and the tip of the new web roll is connected to the web joint. It is placed facing the old web roll in the joining process, and a detection signal for detecting the joining part of the old web roll starts driving the web joining process, and the front end of the new web roll and the old web roll are placed in front of each other. The present invention provides a continuous web splicing method characterized in that the web feeding step and the web tension control step are started at the same time as the splicing of the rolls is performed. Further, the present invention provides an apparatus for use in the above method,
A continuous web splicing device comprising a web roll driving device that unwinds the web from a new web roll, and a web splicing device that splices the leading end of the new web roll to a joining portion such as the terminal end of the old web roll, The web fed out by the web roll drive device is on the path leading to the web splicing device, and when the webs are spliced, the path is shortened so that the web traveling speed in the web splicing device and the speed in the web roll drive device are reduced. A dancer device is provided to absorb the difference in web running speed, and the dancer device includes a dancer arm that is rotatably provided, a dancer roller that is rotatably attached to one end of the dancer arm, and a dancer roller that is rotatably attached to one end of the dancer arm. Provided is a continuous web splicing device, characterized in that it is equipped with a drive device attached to one end and actuated by the input of a detection signal detected regarding the web running speed to rotate the dancer arm. It is. [Embodiment] First, an embodiment of the continuous web splicing apparatus of the present invention used in the method of the present invention shown in the drawings will be described below. Figure 1 is a front view of the main parts of the continuous web splicing device of the present invention, and Figure 2 is a running speed diagram after the new web roll starts to feed out when replacing the old and new web rolls. The apparatus of this embodiment is adapted to be used for automatic joining of backing paper or water-conducting paper in a disposable diaper processing machine. In FIG. 1, 1 is a web roll shaft equipped with a web roll 6, and 7 is the web roll 6.
9 is a web splicing device, and the web roll shaft 1 and the web roll drive device 7 are:
Although not shown, they are arranged not only in the left-hand chain double-dashed line area but also in the right-hand double-dashed line area (the items in the right-hand double-dashed line area are not shown because they are similar to those in the two-dot chain line area on the left). Thus, the apparatus of the present invention is capable of handling the web 1 that is fed out from the left and right web rolls 6, 6, respectively.
0' and 10 are provided with dancer devices A on their respective paths leading to the web splicing device 9. As will be described later, the dancer device A is configured to move the web 1 on the path that is newly fed out.
0' or 10 is relaxed when the web is spliced,
It is designed to absorb the difference between the web running speed in the web splicing device 9 and the web running speed in the corresponding web roll drive device 7. The above-mentioned devices constituting the apparatus of the present invention will be described in detail (as for the devices configured in the same way on the left and right sides as described above, the left side will be described in detail). The drive belt 72 is configured as a device that presses the outer periphery of the web roll 6 from the outside by an air cylinder 71, and at the same time when the web splicing device 9 is activated by a signal that detects the end of the right web 10, The air cylinder 71 is actuated to rotate the web roll 6 in the direction of the arrow. The dancer device A also includes a dancer arm 2 that is rotatably provided around the web roll shaft 1, dancer rollers 3, 3 that are rotatably attached to one end of the dancer arm 2, and a It mainly consists of a linear servo motor 4 attached to the other end to rotate the dancer arm 2, and fixed rollers 8, 8 provided opposite to the dancer rollers 3, 3, respectively, and the rotation angle of the dancer arm 2. a potentiometer 5 for detecting the speed of the web 10', a tachometer generator 11' for detecting the traveling speed of the web 10' in the web roll drive device 7 (the actual speed at which the web 10' is fed out by the web roll drive device 7), and a tachometer generator 11' for detecting the running speed of the web 10' in the web roll drive device 7 (substantial feeding speed of the web 10' by the web roll drive device 7); Web 10 or 10'
tachometer generator 1 that detects the running speed (required speed for feeding out the web 10 or 10' from outside the system)
By controlling the linear servo motor 4 with a control signal based on the detection signal detected in step 1,
Simultaneously with the operation of the web splicing device 9, the dancer arm 2 is rotated clockwise from the origin O so as to be able to absorb the insufficient amount of web roll that occurs when the web roll starts being fed. The web splicing device 9 also includes a pair of nip rollers 91, 91, and a pair of nip rollers 91, 91.
motors 93, 93 that drive the nip rollers 91, 91 during web joining, and clutches 94, 94 that connect and disconnect the motors 93, 93 and the nip rollers 91, 91. The nip rollers 91, 91 are suction rollers for holding the leading end of the web 10' fed out from the left web roll 6, and are connected to a vacuum device (not shown). There is. Next, an embodiment of the continuous web splicing method of the present invention using the above-described continuous web splicing apparatus will be described with reference to the drawings. In an embodiment of the method of the present invention, first, a certain amount of the web 10' wound around the left web roll (hereinafter referred to as new web roll) 6 to be newly unreeled is let out, and then the dancer rollers 3, 3
and fixed guide rollers 8, 8 as shown in FIG.
An adhesive tape (not shown) is attached to the right side surface of the tip of the web 10'. In the preparation state as described above, the right web roll (hereinafter referred to as the old web roll, not shown)
When the web splicing device 9 runs out or is about to run out, a detection signal detecting this runs out.
is activated to carry out a web joining step, and the leading end of the web 10' is joined to the joining portion such as the end of the web 10 via the adhesive tape. That is, the right nip roller 91 is activated by the above detection signal, and the left nip roller 9 is activated by the air cylinder 92.
1, and at the same time the left clutch 9
4 enters, and the left nip roller 9 moves in accordance with the running speed of the web 10 detected by the tacho generator 11.
1 rotates and the web joining process is performed. This web joining process is normally completed while the dancer arm 2, which will be described later, turns by an angle θ ₁ from the origin O. That is, when the dancer arm 2 rotates by an angle θ ₁ from the origin O, the right air cylinder 92
moves backward, releases the vacuum connected to the left nip roller 91, and simultaneously releases the left clutch 94.
The web splicing device 9 is opened by cutting. In addition, if the old web roll of the web 10 is to be spliced to the new web roll 6 of the web 10' before reaching the terminal end, a signal for performing the web splicing process may be input manually.
In this case, it is preferable to provide a step of cutting the web 10 fed out from the old web roll after completion of splicing. At the same time as the above web joining process is started,
The web roll driving device 7 is operated to perform a web unwinding step of unwinding the web 10' from the new web roll, and the web 10' is gradually unwound. That is, the already rotating drive belt 72 is pressed against the outer periphery of the new web roll 6 by the air cylinder 71, so that the new web roll 6 rotates in the direction of the arrow, and the web feeding process is performed. The outer peripheral speed of the new web roll 6 (the speed at which the web 10' is fed out from the new web roll 6) V ₁ in this web feeding step is usually the second
It has a rising characteristic as shown in the figure, and the web 10
(required feeding speed from the disposable diaper processing machine) V ₂ is required for start-up time. Therefore, in order to absorb the insufficient amount of feeding caused by the speed difference V ₂ −V ₁ , at the same time as the web joining process is started, the dancer arm 2 is moved from the origin O by the linear servo motor 4. swivels in a clockwise direction, thereby controlling the tension acting on web 10' as described above and
Dancer device A that absorbs the insufficient amount of delivery of 0'
is activated, a web tension control process is carried out, and the old and new web rolls are spliced together without slowing down the speed _V2 of the web 10. That is, as shown in FIG. 2, when the speed V ₂ of the web 10 is not lowered and is maintained at a constant speed at the normal speed, the outer circumferential speed V ₁ of the new web roll 6 gradually increases, and the speed at which the web 10 is unrolled increases. When ₃ hours T have passed after the start, the speed becomes the same as V ₂ , so there is a shortage in the amount of web fed out. Therefore, the above V ₁ and V ₂ are connected to the tacho generator 1.
1 and 11' and the linear servo motor 4, which is controlled according to the speed difference, is moved backward to rotate the dancer arm 2 clockwise from the origin O, thereby rotating the web 10'. It relaxes and absorbs the amount of insufficient delivery. In addition, to explain the relationship between the turning angle of the dancer arm 2 shown in FIG. 1 and the elapsed time shown in FIG. 2, the dancer arm 2 is at the origin O when the new web roll 6 starts to be fed out, There isn't.
After the web splicing process is completed, the web splicing device 9
The position of dancer arm 2 when released is at a position rotated by θ ₁ from the origin, and the elapsed time is
At T ₁ , the outer peripheral speed V ₁ of the new web roll 6 is still approximately 0 at that time. More time has passed and at T ₂ ,
The dancer arm 2 is located at a position rotated by θ ₂ from the origin O. The time when V ₁ =V ₂ occurs is T ₃ , and at this time the dancer arm 2 is at a position rotated by θ ₃ from the origin. When the web roll drive device 7 starts operating, the drive belt is set at a speed slightly faster than _V2 , so after _T3 , _V1 > _V2 and the linear servo motor 4 changes from backward to forward. The dancer arm 2 then begins to move back toward the origin O. After T ₄ , the speed of the drive belt 72 gradually decreases until T ₅
At this _point , the dancer arm ₂ is controlled to return to the origin O. In this case, increasing the speed of the drive belt 72 can shorten the time until _T5 . After passing T ₅ , the speed becomes approximately V ₁ = V ₂ = the speed of the drive belt 72, and the dancer arm 2 returns to the origin O.
The web 10' can now be supplied in a state where it is fixed to the web 10'. As described above, according to the continuous web splicing method of the present invention, the difference between the web running speed in the web splicing process and the web running speed in the web paying out process is controlled between the web splicing process and the web feeding process. By providing a web tension control process that absorbs and compensates for the insufficient amount of web to be fed out,
Web tension can be controlled. That is, until the speed at which the web is fed out from the new web roll reaches a steady state, the web on the path from the new web roll to the web splicing device is allowed to be fed out in a relaxed state. The difference between the running speed of the web in the combining device and the running speed of the web in the new web roll drive device is absorbed to compensate for the insufficient amount of web being fed out until the speed of feeding out the web from the new web roll reaches a steady state. As a result, continuous automatic splicing of the leading end of the new web roll and the joining portion such as the terminal end of the old web roll can be performed while maintaining the running speed of the web. Although an embodiment of the apparatus of the present invention and an embodiment of the method of the present invention implemented using the apparatus have been described above, the present invention is not limited thereto. For example, a drive roller or the like may be used instead of the drive belt 72 in the web roll drive device 7, and the web roll shaft 1 may be directly driven instead of being brought into pressure contact with the outer periphery of the web roll 6 from the outside. Furthermore, although it is possible to control the tension of the web to approximately the same extent even without the linear servo motor 4 in the dancer device A, in order to reduce the tension acting on the web, it is especially important to provide the linear servo motor 4. desirable. Furthermore, as a detector for controlling the linear servo motor 4, various kinds of detectors may be used instead of the tachometer generators 11, 11' and the potentiometer 5, and the linear servo motor 4 may be used for turning the dancer arm 2. Even if the fulcrum shaft of the dancer arm 2, which is coaxial with the web roll shaft 1, is rotated by a servo motor, the same function can be obtained. Furthermore, the fulcrum of the dancer arm 2 does not have to be provided on the center line of the web roll shaft 1. Furthermore, dancer arm 2
may be one that moves in parallel rather than one that rotates. Although it goes without saying that the web splicing device 9 is not limited to this embodiment, it is preferable that the web splicing device 9 be a device that can perform continuous automatic splicing without reducing the running speed of the web. Next, an example of the continuous web splicing method of the present invention will be described. Example 1 When the backing paper of a disposable diaper was automatically joined using the apparatus shown in Figure 1 under the conditions shown in Table 1 below, the automatic joining was carried out continuously and successfully without causing any cutting of the backing paper. did it. Example 2 A water-conducting paper of a disposable diaper was used in place of the mount in Example 1, and the water-conducting paper was automatically joined using the apparatus shown in FIG. 1 under the conditions shown in Table 1 below. Similarly, automatic splicing could be carried out continuously and satisfactorily without cutting the water-conducting paper.

〔Effect of the invention〕

As described above, the present invention is capable of reducing the leading end of a new web roll and the terminal end of an old web roll while maintaining a steady state running speed without reducing the running speed of the web, even if the web has a low tensile strength. Since it enables continuous automatic joining with joint parts such as, it not only eliminates work time loss, but also eliminates defects in processed products due to changes in operating conditions. It has various advantages.

[Brief explanation of drawings]

Figure 1 is a front view of the main parts of the continuous web splicing device of the present invention, and Figure 2 is a running speed diagram after the new web roll starts to feed out when replacing the old and new web rolls. It shows. A...Dancer device, 2...Dancer arm,
3... Dancer roll, 4... Linear servo motor, 6... Web roll, 7... Web roll drive device, 9... Web splicing device, 10, 10'
...web.

Claims (1)

[Claims] 1. A web splicing process that joins the leading end of a new web roll to a joint such as a terminal end of an old web roll, and a web unwinding process that unwinds the web from the new web roll. In the continuous splicing method, between the web splicing process and the web feeding process, the difference between the web running speed in the web splicing process and the web running speed in the web feeding process is absorbed to prevent insufficient web feeding. A web tension control process that compensates for the amount of web tension, which includes a dancer arm that is rotatably provided, a dancer roller that is rotatably attached to one end of the dancer arm, and a dancer roller that is attached to one end of the dancer arm and that controls the web running speed as described above. A web tension control step is provided which is controlled by a dancer device having a drive device which is actuated by the input of a detection signal detected for the dancer arm to rotate the dancer arm, and the step of controlling the web tension is controlled by a dancer device that rotates the dancer arm. It is placed facing the old web roll in the splicing process, and a detection signal for detecting the spliced part of the old web roll starts driving the web splicing process to connect the tip of the new web roll and the old web roll. A method for continuously splicing a web, characterized in that the web feeding step and the web tension control step are started at the same time as the web is spliced to the splicing portion of the web roll. 2. In a continuous web splicing device comprising a web roll drive device that unwinds the web from a new web roll, and a web splicing device that splices the leading end of the new web roll to a spliced portion such as the terminal end of the old web roll. , the web fed out by the web roll drive device is on the path leading to the web splicing device, and the path is shortened when the webs are spliced, thereby controlling the web traveling speed in the web splicing device and the web roll drive device. A dancer device is provided which absorbs the difference in web running speed at 1. A continuous web splicing device, comprising a drive device attached to one end of the dancer arm and actuated by input of a detection signal detected regarding the web traveling speed to rotate the dancer arm.