JP2020054745A - Manufacturing method of stretchable sheet and manufacturing apparatus of stretchable sheet - Google Patents

Abstract

To fix a cut end part of a rubber thread in a desired bonding pair in a stretchable sheet which fits the rubber thread to a sheet part with a pair of bonding parts located on both sides of the rubber thread.SOLUTION: A manufacturing method of a stretchable sheet (10) arranges a stretched rubber thread (14) in a horizontal direction between a first sheet part (11) and a second sheet part (12), forms a plurality of bonding parts (j) crimping and bonding the first sheet part (11) and the second sheet part (12), cuts the rubber thread (14) at a cut position in the horizontal direction after the stretch state of the rubber thread (14) is relieved, and regulates a position of the rubber thread (14) in the lateral direction by putting after cutting the rubber thread (14) shrunk between a pair of bonding parts (jP) on both sides of the rubber thread (14). In a step relieving the rubber thread (14), the stretching state of at least one part of the rubber thread (14) on one side of the cut position and at least one part of the rubber thread (14) on the other side of the cut position in the lateral direction are relieved.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a method for manufacturing a stretchable sheet and a manufacturing apparatus for a stretchable sheet.

  As a method of manufacturing an elastic sheet, a method of attaching a stretched thread rubber between sheets with an adhesive is known. On the other hand, in Patent Document 1, a thread rubber (wire-like element) in an extended state is disposed between sheets, and the sheet is pressed between a pair of rollers to press the sheet and to cross the thread rubber. A method for forming a connection portion on both sides of the device is disclosed. In a narrow portion formed between the connection portions on both sides of the thread rubber, the thread rubber in a state where the tension is lost and the fat rubber is thickened can be fixed, and the thread rubber can be attached to the sheet. Thus, by attaching the thread rubber to the sheet without using the adhesive, it is possible to suppress a decrease in the shrinkage performance of the thread rubber and a decrease in the flexibility of the stretchable sheet due to the curing of the adhesive.

Japanese Patent No. 3212615

  In the stretch sheet manufactured as described above, the rubber thread may be cut. In this case, the thread rubber is cut off when the interval between the connecting portions (joining portion pairs) formed on both sides of the thread rubber is wide and is equal to or greater than the diameter of the stretched thread rubber or when the stretch ratio of the thread rubber is high. In this case, the thread rubber easily slips between the joints, and there is a possibility that the cut end of the thread rubber cannot be fixed at the desired joint. Then, it becomes impossible to express elasticity in a desired region of the elastic sheet.

  The present invention has been made in view of the above-described problems, and in a stretchable sheet in which thread rubber is attached to a sheet portion at a joint pair located on both sides of thread rubber, a thread rubber is provided at a desired joint pair. The purpose is to fix the cut end of the.

A main invention for achieving the above object is a method for producing a stretchable sheet having a longitudinal direction and a lateral direction, wherein a thread rubber stretched in the lateral direction is provided between a first sheet portion and a second sheet portion. Arranging, forming a plurality of joints by pressing and bonding the first sheet portion and the second sheet portion to each other, and relaxing the stretched state of the thread rubber; Cutting the thread rubber at the cutting position in the lateral direction after the step, wherein the plurality of joints have a joint pair located on both sides of the thread rubber in the longitudinal direction, After the cutting step, the contracted thread rubber is sandwiched between the joining portion pairs, and the lateral position of the thread rubber is regulated. In the relaxing step, the cutting position is set in the lateral direction. Less on one side than Also a portion, and, at least a portion of the other side of the cutting position, a method for producing a stretchable sheet, characterized in that to relieve the tension of the rubber thread.
Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

  According to such an elastic sheet manufacturing method, the cut end of the thread rubber is fixed at the desired joint pair in the elastic sheet in which the thread rubber is attached to the sheet portion at the joint pair located on both sides of the thread rubber. It is easy to be.

It is a top view of the elastic sheet 10 manufactured by the manufacturing method of this embodiment. It is a schematic sectional drawing of the elastic sheet 10 of FIG. It is explanatory drawing of the basic structure of the manufacturing apparatus 20 of an elastic sheet. FIG. 4A is an explanatory view of the surface of the anvil roller 23 and the horn roller 24, and FIG. 4B is a schematic enlarged view of the closest part between the anvil roller 23 and the horn roller 24. 5A and 5B are explanatory diagrams of a method of attaching the thread rubber 14 by the joint j. 6A to 6C are explanatory views of a cutting process of the thread rubber 14. It is explanatory drawing of the relaxation process and cutting process of the thread rubber. It is explanatory drawing of the relaxation process and the cutting process of thread rubber 14 in the modification 1. 9A and 9B are explanatory diagrams of a relaxation step and a cutting step of the thread rubber 14 in the second modification. 10A and 10B are explanatory views of a relaxation step and a cutting step of the thread rubber 14 in the third modification. It is explanatory drawing of the relaxation process and the cutting process of the thread rubber 14 in 2nd Embodiment. It is explanatory drawing of the relaxation process and cutting process of the thread rubber in 3rd Embodiment. It is explanatory drawing of the relaxation process and the cutting process of the thread rubber 14 in 4th Embodiment. It is explanatory drawing of the relaxation process and the cutting process of the thread rubber 14 in 4th Embodiment.

At least the following matters will be made clear by the description in the present specification and the accompanying drawings.
A method for manufacturing a stretchable sheet having a longitudinal direction and a lateral direction, wherein a step of arranging the thread rubber in a laterally stretched state between a first sheet portion and a second sheet portion; Forming a plurality of joints to be bonded to each other by pressing and bonding the second sheet portion, a step of relaxing the stretched state of the thread rubber, and, after the relaxing step, at the cutting position in the lateral direction. Cutting the rubber thread, wherein the plurality of joints have a pair of joints located on both sides of the rubber thread in the longitudinal direction, and after the cutting step, the contracted The thread rubber is sandwiched between the joining portion pairs, the lateral position of the thread rubber is regulated, and in the relaxing step, in the lateral direction, at least a portion on one side from the cutting position, and the Other than the cutting position At least a portion of the side, thereby relieving the tension of the rubber thread.

  According to such an elastic sheet manufacturing method, the thread rubber can be cut in a state in which the diameter of the thread rubber on one side and the other side is larger than the cutting position, and the thread rubber hardly slips between the joints. . Therefore, the cut end portion of the thread rubber is easily fixed at a desired joint portion pair.

  In the method for manufacturing an elastic sheet, in the relaxing step, the thread rubber is relaxed so as to be in a state between the stretched state and the natural state.

  According to such an elastic sheet manufacturing method, the thread rubber that is appropriately stretched can be cut, and the thread rubber can be cut reliably and neatly.

In the method for producing such an elastic sheet, an elongation ratio of the thread rubber in the stretched state is R1, an elongation ratio of the thread rubber relaxed in the relaxing step is R2, When the extension ratio is R3, the extension ratio R2 is represented by the following formula: R2> R3 + (R1-R3) / 2
To meet.

  According to such an elastic sheet manufacturing method, the thread rubber that is appropriately stretched can be cut, and the thread rubber can be cut reliably and neatly.

  In the stretchable sheet manufacturing method, the upstream drive roller supplies a laminate in which the thread rubber is disposed between the first sheet portion and the second sheet portion to the thread rubber cutting device. Then, the downstream drive roller discharges the laminate from the cutting device, and makes the peripheral speed of the upstream drive roller faster than the peripheral speed of the downstream drive roller.

  According to such an elastic sheet manufacturing method, the stretched state of the thread rubber can be relaxed between the upstream drive roller and the downstream drive roller, and the cut end portion of the thread rubber can be formed at a desired joint pair. It is easy to be fixed.

  In the method for manufacturing a stretchable sheet, a second upstream drive roller between the upstream drive roller and the cutting device supplies the laminate to the cutting device, and the downstream drive roller and the cutting device. A second downstream drive roller between the cutting devices discharges the laminate from the cutting device, and makes the peripheral speed of the second upstream drive roller slower than the peripheral speed of the upstream drive roller. The peripheral speed of the second downstream drive roller is higher than the peripheral speed of the second upstream drive roller, and is higher than the peripheral speed of the downstream drive roller.

  According to such an elastic sheet manufacturing method, the cut end portion of the thread rubber is easily fixed at the desired joint portion pair. Furthermore, the thread rubber can be extended between the second upstream drive roller and the second downstream drive roller (that is, around the cutting position), and the thread rubber can be reliably and neatly cut.

  In the method for manufacturing an elastic sheet, the cutting device includes a cutter roller having a cutter blade, and a receiving roller disposed to face the cutter roller, and the peripheral speed of the cutter roller is controlled by the upstream drive. Be faster than the peripheral speed of the roller.

  According to such an elastic sheet manufacturing method, the cut end portion of the thread rubber is easily fixed at the desired joint portion pair. Further, since the cutter blade can cut the thread rubber while extending the thread rubber in the lateral direction, the thread rubber can be cut reliably and neatly.

  In the method for manufacturing an elastic sheet, the cutter blade of the cutting device cuts the laminate by pressing down the laminate in a thickness direction.

  According to such an elastic sheet manufacturing method, the cut end portion of the thread rubber is easily fixed at the desired joint portion pair. Further, since the cutter blade can cut the thread rubber while extending it in the thickness direction of the laminate, the thread rubber can be cut reliably and neatly.

  In the method for manufacturing an elastic sheet, the rubber thread is cut between the first sheet part and the second sheet part while the laminated body in which the rubber thread is arranged is conveyed by a conveyance device, The transporting device has a plurality of holding units for partially holding the laminate, spaced at intervals in the transport direction of the laminate, after narrowing the interval of the holding unit, between the holding unit Cutting the thread rubber located.

  According to such an elastic sheet manufacturing method, the stretched state of the thread rubber located between the holding portions can be relaxed, and the thread rubber whose stretched state has been relaxed can be cut. The pair of thread rubber cut ends can be easily fixed.

  In the method for manufacturing an elastic sheet, the rubber thread is cut between the first sheet part and the second sheet part while the laminated body in which the rubber thread is arranged is conveyed by a conveyance device, A supply roller supplies the laminate to the transport device, and a supply speed of the laminate by the supply roller is higher than a transport speed of the laminate by the transport device, and the transport device transports the laminate. Having a plurality of holding portions for partially holding the stacked members at intervals in the transport direction of the laminated body, cutting the thread rubber located between the holding portions after widening the interval between the holding portions. .

  According to such an elastic sheet manufacturing method, since the rubber thread located between the holding portions can be extended and cut, the rubber thread can be cut reliably and neatly. In addition, the stretched state of the thread rubber located on the holding portion on the upstream side and the downstream side in the transport direction from the cutting position of the thread rubber can be relaxed, and the cut end of the thread rubber is fixed at a desired joint portion pair. It is easy to be.

  In the method for manufacturing an elastic sheet, the rubber thread is cut between the first sheet part and the second sheet part while the laminated body in which the rubber thread is arranged is conveyed by a conveyance device, The conveyance device has a suction unit that partially suctions the laminate and a support unit that partially supports the stack, which are alternately arranged in the conveyance direction of the stack, and the suction units are Cutting the thread rubber located on the suction section after reducing the interval in the transport direction.

  According to such an elastic sheet manufacturing method, the rubber thread extending on the suction portion can be cut, and the rubber thread can be cut reliably and neatly. Further, the stretched state of the thread rubber located between the suction portions, that is, the thread rubber located on the upstream side and the downstream side in the transport direction relative to the cutting position of the thread rubber can be relaxed, and the thread can be threaded at a desired joint portion pair. The cut end of the rubber is easily fixed.

  In the method for manufacturing an elastic sheet, an interval between the joining portion pairs in the longitudinal direction is equal to or larger than a diameter of the thread rubber in the extended state.

  According to such a method of manufacturing an elastic sheet, even when the thread rubber easily slips between the joint portions, the cut end portion of the thread rubber is easily fixed at the desired joint portion pair.

  An apparatus for manufacturing a stretchable sheet having a longitudinal direction and a lateral direction, comprising: a disposing portion that disposes the thread rubber in the laterally extended state between a first sheet portion and a second sheet portion; A joining portion forming a plurality of joining portions for joining the second rubber sheet portion and the second sheet portion by pressure bonding, a relaxing portion for relaxing the stretched state of the thread rubber, and a step for relaxing the horizontal portion after the relaxing step. A cutting portion that cuts the thread rubber at a cutting position in the direction, the plurality of joining portions have a joining portion pair located on both sides of the thread rubber in the longitudinal direction, and the thread rubber is cut. After that, the contracted thread rubber is sandwiched between the joining portion pair, the position of the thread rubber in the lateral direction is regulated, and the relief portion is located on one side of the cutting position in the lateral direction. And the cutting position Remote other side of at least a portion, apparatus for producing a stretchable sheet, characterized in that to relieve the tension of the rubber thread.

  According to such an elastic sheet manufacturing apparatus, the thread rubber can be cut in a state where the thread rubbers on one side and the other side are thicker than the cutting position, and the thread rubber hardly slips between the joints. . Therefore, the cut end portion of the thread rubber is easily fixed at a desired joint portion pair.

=== embodiment ===
<< Configuration of Elastic Sheet 10 >>
FIG. 1 is a plan view of an elastic sheet 10 manufactured by the manufacturing method (manufacturing apparatus) of the present embodiment. FIG. 1 is a view showing a state in which the elastic sheet 10 is stretched without wrinkles. FIG. 2 is a schematic sectional view of the elastic sheet 10 of FIG.

  The stretchable sheet 10 has a transverse direction (stretching direction), a thickness direction, and a longitudinal direction (width direction) orthogonal to each other. Further, the elastic sheet 10 has a first sheet portion 11 and a second sheet portion 12 stacked in the thickness direction, and a plurality of elastic sheets interposed between the first sheet portion 11 and the second sheet portion 12. It has a thread rubber 14 and a plurality of joints j.

  The plurality of thread rubbers 14 are arranged at intervals in the longitudinal direction while being arranged along the lateral direction of the elastic sheet 10. The thread rubber 14 is attached to the first sheet portion 11 and the second sheet portion 12 in an extended state. Therefore, the elastic sheet 10 is provided with elasticity in the direction along the rubber thread 14. As the thread rubber 14 (thread-like elastic member), various known synthetic rubbers such as styrene-based rubber, urethane-based rubber, ester-based rubber, polyurethane, and polyethylene can be applied in addition to thread-like natural rubber.

  The plurality of bonding portions j are for bonding the first sheet portion 11 and the second sheet portion 12 to each other by pressing, and are arranged intermittently in the horizontal direction and the vertical direction of the elastic sheet 10. . Further, the plurality of joints j regulate the horizontal position of the rubber thread 14 with respect to the first sheet portion 11 and the second sheet portion 12. As will be described in detail later, the position of the rubber thread 14 in the horizontal direction is regulated by a pair of joints jP formed on both sides of the rubber thread 14 in the longitudinal direction so as to form a pair. The planar shape of the joint j illustrated in FIG. 1 is rectangular, but the planar shape of the joint j is not particularly limited, and an arbitrary shape such as an ellipse, a circle, a parallelogram, or the like can be adopted.

  Although the elastic sheet 10 in FIG. 2 is composed of two sheets, for example, one sheet is folded, the folded part is a first sheet part, and the unfolded part is a second sheet. It may be a part. Moreover, the elastic sheet 10 in which one or a plurality of different sheet portions are stacked on the first and second sheet portions 11 and 12 may be used. That is, the elastic sheet 10 may have three or more layers.

<< Example of use of elastic sheet 10 >>
The elastic sheet 10 manufactured by the manufacturing method (manufacturing apparatus) of the present embodiment is used as a component of an absorbent article such as a disposable diaper. In that case, a soft sheet member can be exemplified as the first sheet portion 11 and the second sheet portion 12 constituting the elastic sheet 10. For example, it is a nonwoven fabric such as a spunbonded nonwoven fabric and an SMS (spunbond / meltblown / spunbond) nonwoven fabric. Further, at least one of the first sheet portion 11 and the second sheet portion 12 may be a stretchable sheet (a stretchable film or a stretchable nonwoven fabric) that can stretch in the stretchable direction of the stretchable sheet 10. Further, a stretchable film or a stretchable nonwoven fabric may be interposed between the first sheet portion 11 and the second sheet portion 12.

  Specifically, the elastic sheet 10 can be used for the ventral waist portion and the back waist portion of the pants-type disposable diaper. Further, the elastic sheet 10 can be used for leg gather portions provided on both sides of the absorbent main body in the left-right direction of the disposable diaper. Further, in a tape-type disposable diaper (not shown), the elastic sheet 10 can be used for a side panel for attaching a fastening tape (hook member) to the back waistline.

  The elastic sheet 10 is not limited to pants-type or tape-type disposable diapers, but can also be used as a component of absorbent articles such as pad-type disposable diapers, sanitary napkins, and sanitary shorts-type napkins. is there. In addition, it can be used not only for absorbent articles but also for masks, cleaning sheets, and the like.

=== Stretching Sheet Manufacturing Apparatus and Method ===
<< 1st Embodiment >>
(Basic Configuration of Stretchable Sheet Manufacturing Apparatus 20)
FIG. 3 is an explanatory diagram of the basic configuration of the stretch sheet manufacturing apparatus 20 according to the first embodiment. FIG. 4A is an explanatory diagram of the surfaces of the anvil roller 23 and the horn roller 24. FIG. 4B is a schematic enlarged view of the closest part between the anvil roller 23 and the horn roller 24. 5A and 5B are explanatory diagrams of a method of attaching the thread rubber 14 by the joint j.

  The stretch sheet manufacturing apparatus 20 includes a transport roller group 21 (FIG. 4), an ultrasonic welding device 22, a discharge roller 25, a cutter roller 26, and a receiving roller 27. The elastic sheet 10 is manufactured as a continuous sheet continuous in the lateral direction. In the stretch sheet manufacturing apparatus 20, a direction in which the materials are continuous is defined as a transport direction, and a direction orthogonal to the transport direction (that is, the longitudinal direction of the stretch sheet 10) is defined as a CD direction.

  As shown in FIG. 4, the transport roller group 21 is disposed upstream of the ultrasonic welding device 22 in the transport direction, transports the material forming the stretchable sheet 10, and supplies the material to the ultrasonic welding device 22. Specifically, the transport roller group 21 includes a first transport roller 211 that transports a continuum of the first sheet unit 11, a second transport roller 212 that transports a continuum of the second sheet unit 12, and a thread rubber 14. And a third transport roller 213 that transports a plurality of continuous bodies.

  The first to third transport rollers 211 to 213 are rotated around a rotation axis along the CD direction by a drive source (for example, a motor) not shown. The first to third transport rollers 211 to 213 may be a pair of rollers or a single roller. Further, the material may be supplied to the ultrasonic welding device 22 by a belt conveyor or the like.

  Hereinafter, the continuum of the first sheet portion 11, the continuation of the second sheet portion 12, the continuation of the thread rubber 14, and the continuation of the elastic sheet 10 will be simply referred to as the first sheet portion 11, the second sheet portion 12, Also referred to as thread rubber 14 and elastic sheet 10.

  The ultrasonic welding device 22 (joining portion forming portion) is for forming a joining portion j of the elastic sheet 10 and includes an anvil roller 23 and a horn roller 24 that are arranged to face each other. The anvil roller 23 and the horn roller 24 rotate around a rotation axis along the CD direction by a drive source (not shown).

  As shown in FIG. 4A, the outer peripheral surface of the anvil roller 23 is an uneven surface on which a plurality of convex portions 231 are formed. The projections 231 together with the horn roller 24 ultrasonically weld a material to form a joint j. Therefore, the protrusions 231 are arranged corresponding to the arrangement pattern of the joints j in the elastic sheet 10.

  The outer peripheral surface of the horn roller 24 is a smooth surface having no irregularities, and vibrates in a direction in which the distance between the horn roller 24 and the surface of the anvil roller 23 is expanded or contracted (that is, the thickness direction of the material passing therethrough). The frequency of the vibration is, for example, a predetermined value of 20 kHz to 40 kHz, and the amplitude is, for example, a predetermined value of 20 μm to 60 μm. Therefore, the surface of the horn roller 24 is ultrasonically vibrated. Such vibration is generated by inputting an electric signal of the above frequency to a piezo element of a converter (not shown) connected to the horn roller 24.

  In the manufacturing apparatus 20 illustrated in FIG. 3, the first and second sheet portions 11 and 12 and the thread rubber 14 pass between the anvil roller 23 and the horn roller 24 after being wound around the anvil roller 23. The peripheral speed values of the first and second transport rollers 211 and 212 for transporting the first and second sheet portions 11 and 12 are substantially the same as the peripheral speed value of the anvil roller 23, respectively. Therefore, the first and second sheet portions 11 and 12 are wound around the anvil roller 23 in a state where they are stretched to such an extent that they are not substantially stretched and are not loosened.

  On the other hand, the peripheral speed value of the third transport roller 213 that transports the thread rubber 14 is approximately one-half the extension speed of the peripheral speed value of the anvil roller 23. The extension ratio is a ratio R (R = E1 / E0) indicating how many times the total length E1 of the thread rubber 14 in the stretched stretchable sheet 10 is extended to the total length E0 in the unloaded state, which is a natural length. . Therefore, the thread rubber 14 is extended to the above-described stretching magnification while passing between the third transport roller 213 and the anvil roller 23, and is wound around the anvil roller 23 in the extended state.

  The discharge roller 25 is a roller that discharges the semi-finished product of the elastic sheet on which the joint j is formed in a cutting process of the thread rubber 14. The discharge roller 25 is rotated around a rotation axis along the CD direction by a drive source (not shown).

  The cutter roller 26 and the receiving roller 27 (cutting portion) are rollers arranged to face each other on the downstream side in the transport direction from the ultrasonic welding device 22. The cutter roller 26 and the receiving roller 27 rotate around a rotation axis along the CD direction by a drive source (not shown).

  On the outer peripheral surface of the cutter roller 26, a cutter blade 261 protruding outward in the radial direction of the cutter roller 26 is provided. In FIG. 3, two cutter blades 261 are provided at intervals in the rotation direction of the cutter roller 26, but the number of cutter blades is not limited to this. The interval between the cutter blades 261 in the rotation direction corresponds to the interval between the cutting positions of the thread rubber 14. Further, a plurality of thread rubbers 14 arranged in the CD direction (longitudinal direction) in the elastic sheet 10 may be cut by a cutter blade 261 extending in the CD direction, or arranged in a CD direction provided for each thread rubber 14. The cutting may be performed by a plurality of cutter blades 261.

  A receiving blade 271 for receiving the cutter blade 261 of the cutter roller 26 is provided on an outer peripheral surface of the receiving roller 27. However, the receiving roller 27 may not have the receiving blade 271 and may be, for example, a roller having a smooth outer peripheral surface or a roller provided with a groove for receiving the cutter blade 261. .

(Manufacturing method: Step of forming joint j)
In the method of manufacturing the elastic sheet 10 by the manufacturing apparatus 20 having the above-described configuration, first, the transport roller group 21 (arrangement section) supplies the first and second sheet portions 11 and 12 and the thread rubber 14 to the anvil roller 23. Specifically, the thread rubber 14 is supplied such that the thread rubber 14 is located outside the first sheet portion 11 and the thread rubber 14 is located inside the second sheet portion 12 in the radial direction of the anvil roller 23. You. In this way, the rubber thread 14 that is extended in the transport direction (lateral direction) is arranged between the first sheet portion 11 and the second sheet portion 12.

  Next, the first and second sheet portions 11 and 12 and the thread rubber 14 wound around the anvil roller 23 are conveyed to the ultrasonic welding device 22 by the rotation of the anvil roller 23, and between the anvil roller 23 and the horn roller 24. Pass through. At this time, the ultrasonic welding device 22 ultrasonically welds (compresses) the first sheet portion 11 and the second sheet portion 12 to form a plurality of joints j that are joined to each other.

  More specifically, the first and second sheet portions 11 and 12 are melted by ultrasonic vibration from the horn roller 24 at positions corresponding to the convex portions 231 of the anvil roller 23 and are joined. At this time, the thread rubber 14 is located in the groove 232 (see FIGS. 4A and 4B) of the anvil roller 23 and is not subjected to ultrasonic welding. In FIG. 3 and the like, the thread rubber 14 is located on the convex portion 231 of the anvil roller 23 for easy understanding of the drawing. However, the thread rubber 14 is actually located in the groove 232.

  Further, as described above, the plurality of joints j serve to regulate the position of the thread rubber 14 in the lateral direction with respect to the first sheet portion 11 and the second sheet portion 12, that is, the first and second sheets. It also serves to attach the thread rubber 14 to the parts 11 and 12. For this purpose, in this embodiment, as shown in FIG. 1, a plurality of joint pairs jP located on both sides of the thread rubber 14 in the longitudinal direction of the elastic sheet 10 are spaced apart in the lateral direction of the elastic sheet 10. Form. Note that the joint portion pair jP may be continuous in the horizontal direction.

  As shown in FIG. 5A, in the CD direction (longitudinal direction), the distance Dj between the joining portion pair jP located on both sides of the thread rubber 14 is the CD direction of the thread rubber 14 extending at the time of forming the joining portion j. Of diameter D14 or more. Further, it is assumed that the interval Dj is smaller than the diameter of the thread rubber 14 in the CD direction in a naturally long unloaded state. The stretched rubber thread 14 is thinner than the natural thread rubber 14 by the length of the stretched rubber thread. Therefore, after the continuous body of the thread rubber 14 is cut after the formation of the joint j, the stretched state of the thread rubber 14 is relaxed, and as shown in FIG. 5B, the thread rubber 14 tries to expand in the CD direction while contracting in the transport direction. The thread rubber 14 is sandwiched between the joints jP. Thereby, the horizontal position of the thread rubber 14 is regulated, and the thread rubber 14 is attached to the sheet portion.

  However, the present invention is not limited to the above, and the interval Dj between the joint portion pair jP may be smaller than the diameter D14 in the CD direction of the thread rubber 14 extending at the time of forming the joint portion j. That is, the joint j may be formed while the thread rubber 14 is compressed by the space surrounded by the groove 232 of the anvil roller 23 and the horn roller 24. Further, a part of the rubber thread 14 may be pressed together with the first and second sheet portions 11 and 12 by the horn roller 24 and the convex portion 231 of the anvil roller 23. Also in this case, in the elastic sheet 10, the thread rubber 14 is sandwiched between the joints jP, the lateral position of the thread rubber 14 is regulated, and the thread rubber 14 is attached to the sheet portion.

  In addition, the joint forming part that forms the joint j is not limited to the ultrasonic welding device 22 and may be any device that can bond a plurality of sheet portions to each other by pressing. For example, the joint j (heat-welded portion) may be formed using a heat sealing device. The heat sealing device is a pair of heated rollers, one roller is a roller having a convex portion corresponding to the joint j on the outer peripheral surface, and the other roller is a roller having the convex portion having a smooth outer peripheral surface. Can be exemplified as a roller which is received by the roller.

  Further, FIG. 3 illustrates the ultrasonic welding device 22 including a pair of rollers, but is not limited thereto. Instead of the horn roller 24, a non-rotating horn having a flat vibration surface disposed opposite to the surface of the anvil roller 23 may be used. Alternatively, the horn side that performs ultrasonic vibration may be a roller-shaped device, and the anvil side may be a device that is non-rotating and has a flat surface that receives ultrasonic vibration. Further, the vibration surface on the horn side may be an uneven surface, and the surface on the anvil side may be a smooth surface. Further, both the horn side and the anvil side surfaces may be uneven surfaces.

(Manufacturing method: Step of cutting thread rubber 14)
FIGS. 6A to 6C are diagrams illustrating the thread rubber 14 and the joint portion pair jP in the elastic sheet 10, and are explanatory diagrams of a cutting process of the thread rubber 14. FIG. 7 is an explanatory view of a relaxation step and a cutting step of the thread rubber 14.

  The method for manufacturing the elastic sheet 10 of the present embodiment includes a step of cutting the thread rubber 14 after forming the joint j. Therefore, as shown in FIG. 3, the stacked body 10 ′ of the first and second sheet portions 11 and 12 and the thread rubber 14 on which the joint j is formed is transported by the discharge roller 25, and the cutter roller 26 and the receiving roller It passes between the rollers 27. At this time, the cutter blade 261 is inserted into the laminated body 10 ′ supported by the receiving blade 271, and the thread rubber 14 is cut.

  In the step of cutting the thread rubber 14, the first sheet portion 11 and the second sheet portion 12 may be cut and separated together with the thread rubber 14, or only the thread rubber 14 may be cut and separated. The first sheet portion 11 and the second sheet portion 12 may not be separated.

  For example, when the continuous body of the stretchable sheet 10 is cut into a component size of an absorbent article, the first sheet portion 11 and the second sheet portion 12 may be cut and separated together with the rubber thread 14. On the other hand, the elasticity may be partially removed from the elastic sheet 10. For example, when the elastic sheet 10 is used for the ventral waist portion and the back waist portion of a pants-type disposable diaper, in order to secure the flatness of the absorbent main body, the abdominal waist portion and the back waist portion are used. The elasticity may be removed from the portion overlapping the absorbent body. In this case, the central portion of the rubber thread 14 extending in the lateral direction in the elastic sheet 10 may be cut and separated so that the first sheet portion 11 and the second sheet portion 12 are not separated. However, when the first sheet portion 11 and the second sheet portion 12 are separated together with the thread rubber 14, no cut marks remain on the elastic sheet 10, so that the appearance of the elastic sheet 10 can be improved.

  Moreover, in the elastic sheet 10, elasticity is developed from the position where the cut end 14a of the cut thread rubber 14 is fixed by the joint portion pair jP. For example, as shown in FIG. 6A, a joining portion pair adjacent to the cutting position Pc of the thread rubber 14 in the lateral direction is a first joining portion pair jP1, and a pair of joining portions on the side opposite to the cutting position with respect to the first joining portion pair jP1. The joining portion pair is referred to as a second joining portion pair jP2. When the cut end portion 14a of the thread rubber 14 is fixed by the first joint portion pair jP1, elasticity is developed on the side opposite to the cutting position from the first joint portion pair jP1.

  Therefore, the joint portion pair jP to which the cut end portion 14a of the thread rubber 14 is to be fixed is determined according to the region in the elastic sheet 10 where the elasticity is desired to be exhibited. However, as shown in FIG. 5A, when the distance Dj between the joining portion pair jP in the longitudinal direction is relatively wide and is equal to or greater than the diameter D14 of the thread rubber 14 that is elongated at the time of forming the joining portion j, the thread after cutting is cut. The rubber 14 easily slips through between the joint pair jP. Further, even when the distance Dj between the joint portion pair jP is smaller than the diameter D14 of the rubber thread 14 extending at the time of forming the joint portion j, if the elongation ratio of the rubber thread 14 is high, the elasticity of the thread rubber 14 is increased. The contraction force after cutting is strong, and the thread rubber 14 easily slips between the joints jP.

  Therefore, even if it is desired to fix the cut end portion 14a of the thread rubber with the first joint portion pair jP1, simply cutting the thread rubber 14 causes the thread rubber 14 to move between the first joint portion pair jP1. There is a possibility that the thread rubber 14 will pass through and be fixed at the second joint portion pair jP2, or the thread rubber 14 will be fixed at the joint pair jP on the side opposite to the cutting position with respect to the second joint portion jP2.

  Therefore, in the manufacturing method of the present embodiment, the step of relaxing the stretched state of the rubber thread 14 when the rubber thread 14 is disposed on the sheet portions 11 and 12 and the step of cutting the rubber thread 14 after the relaxing step are performed. Have. In the relaxing step, the elongation of the rubber thread 14 in at least a part of the thread rubber 14 on one side from the cutting position Pc and at least a part on the other side of the cutting position Pc in the lateral direction is relaxed.

  At least a part on one side and the other side of the cutting position Pc of the thread rubber 14 is defined as the thread rubber 14 around the joint pair jP (here, the first joint pair jP1) where the cut end 14a of the thread rubber is to be fixed. Part. By doing so, as shown in FIGS. 6B and 6C, before cutting the thread rubber 14, the stretched state of the thread rubber 14 around the first joint portion pair jP <b> 1 is relaxed, and the diameter of the thread rubber 14 is increased. Become. Therefore, after the thread rubber 14 is cut, the thread rubber 14 does not easily pass through the first joint portion pair jP1.

  As described above, according to the manufacturing method of the present embodiment, the distance Dj between the joining portion pair jP in the longitudinal direction is equal to or larger than the diameter D14 of the stretched rubber thread 14 or the stretching magnification of the rubber thread 14 is high. Even when the thread rubber 14 easily slips between the joints jP, the cut end 14a of the thread rubber is easily fixed at the desired joint jP. Therefore, it is possible to prevent the stretchable region of the stretchable sheet 10 from being narrowed, and to exhibit stretchability in a desired region of the stretchable sheet 10.

  The portion of the thread rubber 14 that does not include the desired joint pair jP to which the cut end portion 14a of the thread rubber is desired to be fixed may be relaxed. However, preferably, a portion of the rubber thread 14 including the rubber thread 14 located between the desired joint portion pair jP may be relaxed. By doing so, the diameter of the thread rubber 14 located between the desired joint portion pair jP is increased, and the thread rubber 14 can be cut while the thread rubber 14 is sandwiched between the desired joint portion pair jP. 14 is harder to slip through from the desired joint pair jP.

  In addition, as shown in FIG. 6B, the thread rubber 14 may be cut in a state where the stretched state of the thread rubber 14 located at the cutting position Pc is relaxed, or as shown in FIG. The rubber thread 14 may be cut in a state where the stretched state of the rubber thread 14 is not relaxed.

  In FIG. 6A, the first joint portion pair jP1 located immediately adjacent to the cutting position Pc of the thread rubber 14 is the joint portion pair jP for fixing the cut end portion 14a of the thread rubber, but is not limited thereto. . That is, the N-th (N ≧ 2) joining portion pair jP from the cutting position Pc of the thread rubber 14 may be the joining portion pair jP for fixing the cut end portion 14a of the thread rubber.

  Further, it is preferable that the diameter of the thread rubber 14 in which the stretched state has been relaxed is equal to or more than the distance (Dj in FIG. 5A) between the joints jP in the longitudinal direction. By doing so, it becomes more difficult for the thread rubber 14 to slip through the desired joint portion pair jP.

  However, if the stretched state of the thread rubber 14 is excessively relaxed, the thread rubber 14 becomes difficult to be cut (especially when the thread rubber 14 at the cutting position Pc is relaxed as shown in FIG. 6B). Therefore, the state between the elongation state (elongation magnification at) when the rubber thread 14 is disposed on the sheet portions 11 and 12 and the state (elongation magnification at) at no load and the natural state (elongation magnification at) are shown. Therefore, the thread rubber 14 may be relaxed. By doing so, the thread rubber 14 that is appropriately extended can be cut, and the thread rubber 14 can be cut reliably and neatly.

Further, the elongation magnification of the thread rubber 14 in the stretched state in which the thread rubber 14 is disposed on the sheet portions 11 and 12 is R1, and the elongation magnification of the thread rubber 14 relaxed in the relaxing step is R2. Is defined as R3 (= 1), the extension ratio R2 is expressed by the following equation: R2> R3 + (R1-R3) / 2
It is good to satisfy.

  By doing so, it is possible to cut the thread rubber 14 having the extension ratio R2 closer to the extension ratio R1 in the extended state than in the natural state, and to cut the thread rubber 14 reliably and neatly. As described above, the extension ratio is a magnification R (R = E1 / E0) indicating how many times the entire length E1 of the rubber thread 14 in the stretched state is extended to the total length E0 of the rubber thread 14 in the natural state. It is.

  Further, as shown in FIG. 7, the extended state of the first sheet portion 11 and the second sheet portion 12 together with the thread rubber 14 is also eased. Therefore, by relaxing the elongation ratio of the thread rubber 14 so as to be as described above, the sheet portions 11 and 12 can be conveyed while appropriately applying tension, and the conveyance is stabilized.

  Then, the manufacturing apparatus 20 of the first embodiment has an upstream drive roller 30 and a downstream drive roller 31 as a relaxation portion for relaxing the stretched state of the thread rubber 14, as shown in FIG. Each of the upstream drive roller 30 and the downstream drive roller 31 is a pair of nip rollers that rotate around a rotation axis along the CD direction by a drive source (not shown). Both of the pair of nip rollers may be driving rollers, or one may be a driving roller and the other may be a driven roller.

  The upstream drive roller 30 is disposed between the ultrasonic welding device 22 (discharge roller 25) shown in FIG. 3 and the cutter roller 26 and the receiving roller 27 (hereinafter, also referred to as a "thread rubber cutting device"). The upstream drive roller 30 transfers the laminated body 10 ′ in which the thread rubber 14 is disposed between the first sheet portion 11 and the second sheet portion 12 and the joint j is formed to the thread rubber cutting devices 26 and 27. Supply.

  The downstream drive roller 31 is disposed downstream of the thread rubber cutting devices 26 and 27. The downstream drive roller 31 discharges the laminate 10 ′ from the thread rubber cutting devices 26 and 27 and supplies the laminate 10 ′ to downstream processes.

  The peripheral speed V1 of the upstream drive roller 30 is set to be higher than the peripheral speed V2 of the downstream drive roller 31 (V1> V2). That is, the amount (the length per unit time, for example, m / sec) of the laminated body 10 ′ that the upstream drive roller 30 sends out toward the thread rubber cutting devices 26 and 27 is determined by the downstream drive roller 31 The amount is larger than the amount (length per unit time, for example, m / sec) of the stacked body 10 'sent out to the process.

  Therefore, between the upstream drive roller 30 and the downstream drive roller 31, the stretched state of the laminated body 10 'is relaxed, and the stretched state of the thread rubber 14 is also relaxed. Specifically, as shown in FIG. 6B, it is possible to relax the stretched state of the thread rubber 14 in a part on one side in the lateral direction and a part on the other side of the cutting position Pc, including the cutting position Pc of the thread rubber 14. The thread rubber 14 can be cut in a state where the diameter of the thread rubber 14 is increased. Therefore, the cut end portion 14a of the thread rubber can be fixed at the first joint portion pair jP1 (a desired joint portion pair jP).

(Modification 1)
FIG. 8 is an explanatory diagram of a relaxation step and a cutting step of the thread rubber 14 in the first modification. In the first modification, the second upstream drive roller 32 is disposed between the upstream drive roller 30 and the thread rubber cutting devices 26 and 27, and the second rubber drive device 30 and the downstream rubber drive device 31 are separated from each other. In between, a second downstream drive roller 33 is arranged.

  Each of the second upstream drive roller 32 and the second downstream drive roller 33 is a pair of nip rollers that rotate around a rotation axis along the CD direction by a drive source (not shown). Both of the pair of nip rollers may be driving rollers, or one may be a driving roller and the other may be a driven roller. The second upstream drive roller 32 supplies the laminate 10 ′ to the thread rubber cutting devices 26 and 27, and the second downstream drive roller 33 supplies the laminate 10 ′ to the thread rubber cutting devices 26 and 27. Discharged from

  The peripheral speed V3 of the second upstream drive roller 32 is set to be lower than the peripheral speed V1 of the upstream drive roller 30 (V3 <V1). By doing so, the amount (e.g., m / sec) of the stacked body 10 ′ that the upstream drive roller 30 sends out downstream is the amount of the stacked body 10 ′ that the second upstream drive roller 32 sends out downstream (eg: m / sec). Therefore, between the upstream drive roller 30 and the second upstream drive roller 32, the stretched state of the laminate 10 'is relaxed, and the stretched state of the thread rubber 14 is also relaxed.

  The peripheral speed V4 of the second downstream drive roller 33 is set to be faster than the peripheral speed V3 of the second upstream drive roller 32 (V4> V3). By doing so, the amount (e.g., m / sec) of the laminate 10 ′ sent out by the second upstream drive roller 32 to the downstream depends on the amount of the laminate 10 ′ sent out by the second downstream drive roller 33. (Example: m / sec). Therefore, between the second upstream drive roller 32 and the second downstream drive roller 33, the laminate 10 '(the rubber thread 14) is extended again.

  The peripheral speed V4 of the second downstream drive roller 33 is set to be higher than the peripheral speed V2 of the downstream drive roller 31 (V4> V2). By doing so, the amount (e.g., m / sec) of the stacked body 10 'that the second downstream drive roller 33 sends out downstream is equal to the amount of the stacked body 10' that the downstream drive roller 31 sends out downstream (e.g., m / sec). Therefore, between the second downstream drive roller 33 and the downstream drive roller 31, the stretched state of the laminated body 10 'is relaxed again, and the stretched state of the thread rubber 14 is relaxed again.

  In this case, the extension ratio of the thread rubber 14 between the second upstream drive roller 32 and the second downstream drive roller 33, that is, the periphery of the cutter blade 261 is determined by the upstream drive roller 30 and the second upstream drive. It is higher than the extension ratio of the rubber thread 14 between the rollers 32 and between the second downstream drive roller 33 and the downstream drive roller 31. Therefore, the thread rubber 14 which is appropriately extended can be cut, and the thread rubber 14 can be cut reliably and neatly.

  Further, at a portion on the upstream side in the transport direction from the cutter blade 261 and a portion on the downstream side in the transport direction from the cutter blade 261, the stretched state of the thread rubber 14 is relaxed, and the diameter of the thread rubber 14 increases. I have. Therefore, the cut end portion of the thread rubber 14 is easily fixed at the desired joint portion pair jP. That is, in the first modification, the thread rubber 14 can be cut in the state shown in FIG. 6C.

  In the first modification, the thread rubber cutting position Pc is adjusted by adjusting the distance between the cutter blade 261 and the second upstream drive roller 32 and the distance between the cutter blade 261 and the second downstream drive roller 33. The length from the position to the position where the stretched state of the thread rubber 14 is relaxed can be adjusted. Therefore, it is possible to increase the diameter of the thread rubber 14 around the joint pair jP apart from the thread rubber cutting position Pc, instead of the joint portion pair (the first joint portion pair jP1) closest to the thread rubber cutting position Pc. That is, the cut end portion 14a of the thread rubber can be fixed at the desired joint jP remote from the cutting position Pc of the thread rubber.

(Modification 2)
9A and 9B are explanatory diagrams of a relaxation step and a cutting step of the thread rubber 14 in the second modification. FIG. 9B is an enlarged view around the cutter blade 261. In FIG. 9B, the first sheet portion 11 and the second sheet portion 12 are omitted to avoid complication of the drawing.

  The manufacturing apparatus of the second modification has the same configuration as that of the above-described embodiment (FIG. 7). However, in Modification 2, the peripheral speed V5 of the cutter roller 26 is set to be higher than the peripheral speed V1 of the upstream drive roller 30 and higher than the peripheral speed V2 of the downstream drive roller 31. (V5> V1> V2).

  By doing so, the stretched state of the thread rubber 14 is reduced between the upstream drive roller 30 and the downstream drive roller 31 as in the above-described embodiment (FIG. 7). Therefore, the thread rubber 14 can be cut in a state where the diameter of the thread rubber 14 is increased around the desired joint portion pair jP, and the cut end of the thread rubber 14 can be fixed at the desired joint portion pair jP.

  Further, in the second modification, the moving speed (rotation speed) of the cutter blade 261 is faster than the transport speed of the thread rubber 14 fed by the upstream drive roller 30. For this reason, as shown in FIG. 9B, the thread is transferred to the cutter blade 261 moving at a high speed between the time when the thread rubber 14 is hooked on the cutter blade 261 and the time when the thread rubber 14 is sandwiched between the cutter blade 261 and the receiving roller 27 and cut. The rubber 14 is pulled. Therefore, a part of the thread rubber 14 on the upstream side of the cutter blade 261 extends, and the cutter blade 261 can cut the thread rubber 14 while extending the thread rubber 14 in the transport direction (lateral direction). Therefore, the thread rubber 14 can be reliably and neatly cut.

  The cutter roller 26 (cutter blade 261) and the receiving roller 27 come into contact when the rubber thread 14 is cut. Therefore, the transport speed of the laminated body 10 ′ that has passed between the cutter roller 26 and the receiving roller 27 does not change, and the thread rubber 14 downstream of the cutter roller 26 also maintains the relaxed state.

(Modification 3)
10A and 10B are explanatory diagrams of a relaxation step and a cutting step of the thread rubber 14 in the third modification. FIG. 10B is an enlarged view around the cutter blade 261. In FIG. 10B, the first sheet portion 11 and the second sheet portion 12 are omitted to prevent the drawing from being complicated.

  The manufacturing apparatus of the third modification has the same configuration as that of the above-described embodiment (FIG. 7). Therefore, the stretched state of the rubber thread 14 is reduced between the upstream drive roller 30 and the downstream drive roller 31. Therefore, the thread rubber 14 can be cut in a state where the diameter of the thread rubber 14 is increased around the desired joint portion pair jP, and the cut end of the thread rubber 41 can be fixed at the desired joint portion pair jP.

  Further, in Modification 3, the cutter blade 261 of the cutter roller 26 cuts the laminate 10 ′ (the rubber thread 14) by pushing down the laminate 10 ′ in the thickness direction. Therefore, in the up-down direction (in the thickness direction of the laminated body 10 ′), the nip position h 1 of the upstream drive roller 30 and the nip position h 1 of the downstream drive roller 31 are larger than the nip position h 1 of the cutter blade 261 and the receiving roller 27. The contact position h2 (the cutting position of the thread rubber) is shifted downward (toward the receiving roller 27) in the vertical direction.

  By doing so, as shown in FIG. 10B, the thread rubber 14 hooked on the cutter blade 261 is pushed down by the cutter blade 261. Therefore, the cutter blade 261 can cut the thread rubber 14 while extending it in the thickness direction of the laminate 10 ′, and can cut the thread rubber 14 reliably and neatly.

  The rotary cutter blade 261 in which the roller is provided with the cutter blade 261 has been described as an example, but is not limited thereto. The device for cutting the thread rubber 14 (other than the modified example 2) may be, for example, a device in which at least one of the cutter blade and the receiving blade moves in the vertical direction to pinch and cut the thread rubber 14.

=== Second Embodiment ===
FIG. 11 is an explanatory diagram of a relaxation step and a cutting step of the thread rubber 14 in the second embodiment. The manufacturing apparatus according to the second embodiment includes a supply roller 50, a transport device 40, a cutter roller 26, and a discharge roller 51 downstream of the ultrasonic welding device 22 and the discharge roller 25 (see FIG. 3). In the second embodiment, the supply roller 50 supplies the conveying device 40 with the laminate 10 ′ in which the thread rubber 14 is disposed between the first sheet portion 11 and the second sheet portion 12 and the joint j is formed. Then, the thread rubber 14 is cut while the laminate 10 ′ is transported by the transport device 40.

  The transfer device 40 is a substantially drum-shaped device that rotates around a rotation axis along the CD direction, and transfers the stacked body 10 ′ along the rotation direction of the transfer device 40. The transport device 40 has a plurality of holding portions 41a to 41f that partially hold the stacked body 10 'at intervals in the rotation direction of the transport device 40 (that is, the transport direction of the stacked body 10'). Each of the holding units 41a to 41f has a suction mechanism (not shown), and conveys the stacked body 10 'while adsorbing the surface of the holding units 41a to 41f. The holding units 41a to 41f can be moved in the rotation direction by a drive mechanism (not shown) while rotating in the rotation direction of the transport device 40, and the interval between the holding units 41a to 41f adjacent in the rotation direction can be changed. Has become.

  In the second embodiment, the transport speed V6 of the stacked body 10 ′ on the upstream side of the transport device 40 is substantially the same as the transport speed V6 of the stacked body 10 ′ by the transport device 40 (the peripheral speed of the transport device 40). It is set to be. Therefore, the stretched state of the laminated body 10 ′ (the rubber thread 14) transferred from the supply roller 50 to the holding unit (for example, 41 a) is maintained.

  Thereafter, on the upstream side of the cutter roller 26, the holding unit (eg, 41 a) is moved downstream in the transport direction so as to approach an adjacent holding unit (eg, 41 b) on the downstream side of the holding unit (eg, 41 a). Move to the side. Therefore, the angle formed by the adjacent holding portions 41a to 41f is smaller when the holding portions 41a to 41f approach the cutter roller 26 than the angle θ1 when the stacked body 10 is delivered to the holding portions 41a to 41f. The angle θ2 is smaller (θ1> θ2).

  Further, the stacked body 10 'suction-held by the holding units 41a to 41f does not shift in the transport direction. For this reason, the holding portion (eg, 41a) approaches the holding portion (eg, 41b) on the downstream side, and the distance between the holding portions (eg, 41a and 41b) is reduced, so that the gap between the holding portions (eg, 41a and 41b) is reduced. Is relaxed, and the stretched state of the thread rubber 14 is also relaxed. That is, the transport device 40 functions as a relaxation portion that relaxes the stretched state of the rubber thread 14.

  Thereafter, the thread rubber 14 located between the holding portions 41a to 41f is cut by the cutter blade 261. By doing so, the stretched state of the thread rubber 14 can be relaxed around the cutting position of the thread rubber 14, and the cut end of the thread rubber 14 is easily fixed at a desired joint portion pair jP.

  Preferably, a desired joint jP to which the cut end of the rubber thread 14 is desired to be fixed is located in the laminate 10 ′ located between the holding portions 41 a to 41 f. By doing so, the thread rubber 14 can be cut while the diameter of the thread rubber 14 around the desired joint portion pair jP is increased, and the cut end of the thread rubber 14 can be fixed with the desired joint portion pair jP.

Although not shown, a receiving portion (receiving blade) for receiving the cutter blade 261 may be provided between the holding portions 41a to 41f.
In addition, the holding unit (eg, 41f) that has delivered the stacked body 10 ′ to the discharge roller 51 has an interval (angle) with the holding unit (eg, 41a) on the downstream side when receiving the stacked body 10 ′ (angle). θ1).
In addition, the stacked body 10 ′ is suction-held by the holding units 41a to 41f, but is not limited thereto. It is sufficient that the laminated body 10 ′ on the holding portions 41 a to 41 f does not shift.

=== Third Embodiment ===
FIG. 12 is an explanatory view of a relaxation step and a cutting step of the thread rubber 14 in the third embodiment. The manufacturing apparatus according to the third embodiment also includes a supply roller 50, a transport device 40, a cutter roller 26, and a discharge roller 51, and transports the stacked body 10 ′ by the transport device 40, as in the second embodiment. While cutting, the rubber thread 14 is cut.

  Further, the configuration of the transport device 40 is the same. That is, the transport device 40 has a plurality of holding portions 41a to 41g that partially hold the stacked body 10 '. The holding units 41a to 41g can change the distance between the holding units 41a to 41g adjacent to each other in the rotation direction while rotating in the rotation direction of the transport device 40.

  However, in the third embodiment, the supply speed V7 of the laminated body 10 ′ by the supply roller 50 (the peripheral speed of the supply roller 50) is equal to the transport speed V8 of the laminated body 10 ′ by the transport device 40 (the peripheral speed of the transport device 40). (V7> V8). That is, the amount (eg, m / sec) of the stacked body 10 ′ which the supply roller 50 sends out to the transport device 40 is larger than the amount (eg, m / sec) of the stacked body 10 ′ transported by the transport device 40. ing. Therefore, the stretched state of the laminate 10 ′ on the transport device 40 is relaxed, and the stretched state of the rubber thread 14 is relaxed.

  As described above, in the third embodiment, the supply roller 50 and the transport device 40 function as a relaxation unit that relaxes the stretched state of the rubber thread 14. Further, the transport speed V8 of the stacked body 10 ′ by the transport device 40 is such that after the stacked body 10 is delivered to the holding unit (eg, 41a), the holding unit (eg, 41a) and the downstream holding unit (eg, 41a). Example: The transport speed in a period before the interval with 41b) changes.

  Further, before the cutter blade 261 cuts the thread rubber 14 between the holding portion (eg, 41d) and the adjacent holding portion (eg, 41c) on the upstream side, the downstream holding portion (eg, 41d). ) Moves to the downstream side in the transport direction so as to move away from the upstream holding unit (eg, 41c). Therefore, regarding the angle formed by the adjacent holding portions 41a to 41g, the angle when the holding portions 41a to 41g approach the cutter roller 26 is smaller than the angle θ3 when the stacked body 10 is delivered to the holding portions 41a to 41g. The angle θ4 is larger (θ3 <θ4). As described above, by increasing the interval between the holding portions 41a to 41g, the laminate 10 'located between the holding portions (eg, 41d and 41c) is elongated, and the rubber thread 14 is also elongated.

  Thereafter, the stretched thread rubber 14 located between the holding portions 41a to 41g is cut by the cutter blade 261 and a receiving portion (receiving blade) (not shown). By doing so, the thread rubber 14 can be reliably and neatly cut.

  In addition, the stretched state of the thread rubber 14 in a part on the upstream side and a part on the downstream side in the transport direction from the cutting position of the thread rubber 14 is reduced. Therefore, the cut end portion of the thread rubber 14 is easily fixed at a desired joint portion pair jP. Preferably, a desired joint pair jP to which the cut end of the thread rubber 14 is desired to be fixed is located on the holding body 41a-41g and the laminated body 10 'in which the stretched state is relaxed. . By doing so, the thread rubber 14 can be cut while the diameter of the thread rubber 14 around the desired joint portion pair jP is increased, and the cut end of the thread rubber 14 can be fixed at the desired joint portion pair jP.

  In addition, the holding part (example: 41d) which moves to the downstream side in order to widen the interval between the holding parts 41a to 41g is provided between the holding part (example: 41d) and the downstream holding part (example: 41e). After the thread rubber 14 has been cut, it may be moved.

=== Fourth Embodiment ===
FIG. 13 and FIG. 14 are explanatory diagrams of a relaxation step and a cutting step of the thread rubber 14 in the fourth embodiment. Similarly to the second and third embodiments, the manufacturing apparatus according to the fourth embodiment also includes a supply roller 50, a transport device 40, a cutter roller 26, and a discharge roller 51, and transfers the stacked body 10 ′ to the transport device. The thread rubber 14 is cut while being transported by 40.

  The transport device 40 illustrated in FIG. 13 is a substantially drum-shaped device that rotates around a rotation axis along the CD direction, and transports the stacked body 10 ′ along the rotational direction of the transport device 40. The transport device 40 includes suction units 42a to 42f that partially suction the stacked body 10 ′ by a suction mechanism (not shown) and support units 43a to 43f that partially support the stacked body 10 ′. In the conveying direction.

  The suction units 42a to 42f can move in the rotation direction by a drive mechanism (not shown) while rotating in the rotation direction of the transport device 40, and can move the gaps between the suction units 42a to 42f and the gaps between the support units 43a to 43f. It can be changed. On the other hand, the support portions 43a to 43f rotate while maintaining a constant interval between the support portions 43a to 43f. Further, the stacked body 10 'delivered to the suction units 42a to 42f is adsorbed on the surfaces of the suction units 42a to 42f, does not shift in position, and is maintained in the extended state. On the other hand, the stacked body 10 'delivered to the support portions 43a to 43f can be displaced with respect to the support portions 43a to 43f while being conveyed by the support portions 43a to 43f, and the stretched state can be relaxed. I have.

  In the fourth embodiment, the transport speed V6 of the stacked body 10 ′ on the upstream side of the transport device 40 is substantially the same as the transport speed V6 of the stacked body 10 ′ by the transport device 40 (the peripheral speed of the transport device 40). It is set to be. Therefore, the laminated body 10 ′ transferred from the supply roller 50 to the suction unit (for example, 42 a) or the support unit (for example, 43 a) is maintained in the extended state.

  Then, on the upstream side of the cutter roller 26, the suction unit (eg, 42a) is connected to the adjacent support unit (eg, 43a) and suction unit (eg, 42b) downstream of the suction unit (eg, 42a). It moves to the downstream side in the transport direction so as to approach. Therefore, regarding the angle formed by the adjacent suction units 42a to 42f, the angle when the holding units 41a to 41f approach the cutter roller 26 is smaller than the angle θ5 when the stacked body 10 is delivered to the suction units 42a to 42f. The angle θ6 is smaller (θ5> θ6).

  The suction unit (eg, 42a) approaches the suction unit (eg, 42b) on the downstream side, and the distance between the suction units (eg, 42a and 42b) is reduced, so that the space between the suction units (eg, 42a and 42b) is reduced. The stretched state of the laminated body 10 'located is relaxed, and the stretched state of the rubber thread 14 is also relaxed. That is, the transport device 40 functions as a relaxation portion that relaxes the stretched state of the rubber thread 14.

  Thereafter, the thread rubber 14, which is located on the suction units 42a to 42f and extends, is cut by the cutter blade 261 and a receiving unit (receiving blade) (not shown). By doing so, the thread rubber 14 can be reliably and neatly cut.

  In addition, the stretched state of the thread rubber 14 in a part on the upstream side and a part on the downstream side in the transport direction from the cutting position of the thread rubber 14 is reduced. Therefore, the cut end portion of the thread rubber 14 is easily fixed at a desired joint portion pair jP. Preferably, a desired joint portion pair jP to which the cut end of the thread rubber 14 is to be fixed is located in the laminated body 10 ′ that is located between the suction portions 42 a to 42 f and whose stretched state is relaxed. . By doing so, the thread rubber 14 can be cut while the diameter of the thread rubber 14 around the desired joint portion pair jP is increased, and the cut end of the thread rubber 14 can be fixed with the desired joint portion pair jP.

  14, the suction units 42a to 42f may be provided inside the hollow cylindrical support drum 40 that is continuous in the rotation direction of the transfer device 40, as in the transfer device 40 illustrated in FIG. The suction units 42a to 42f can change the distance between the suction units 42a to 42f while rotating in the rotation direction of the transport device 40 inside the support drum 40. The support drum 40 rotates in the rotation direction of the transport device 40, and transports the stacked body 10 'transferred on the outer peripheral surface. The support drum 40 is provided with a suction hole 44a penetrating in the radial direction of the support drum 40. Therefore, the portion of the support drum 40 that overlaps the suction units 42a to 42f corresponds to the suction unit of the present invention, and transports the stacked body 10 'while maintaining the stretched state of the stacked body 10'. On the other hand, the portion of the support drum 40 that does not overlap with the suction units 42a to 42f corresponds to the support unit of the present invention, and conveys the laminate 10 'while allowing the stretched state of the laminate 10' to be reduced.

  In the case of the transport device 40 in FIG. 14 as well, it is preferable that the interval between the suction units (for example, 42a and 42b) be narrowed after the stacked body 10 'is transferred to the support drum 40 in an extended state. By doing so, the stretched state of the laminated body 10 ′ located between the suction portions (eg, 42 a and 42 b) is relaxed, and the stretched state of the thread rubber 14 is also relaxed. Thereafter, the thread rubber 14 on the suction units 42a to 42f, which is maintained in the extended state, may be cut by being sandwiched between the cutter blade 261 and the support drum 40. By doing so, the cut end portion of the thread rubber 14 can be easily fixed at a desired joint portion pair jP while reliably and neatly cutting the thread rubber 14.

  As described above, the embodiments of the present invention have been described. However, the above embodiments are for the purpose of facilitating the understanding of the present invention, and are not intended to limit and interpret the present invention. Further, the present invention can be changed or improved without departing from the gist thereof, and it goes without saying that the present invention includes equivalents thereof.

10 elastic sheet, 10 'laminate,
11 first sheet portion, 12 second sheet portion, 14 thread rubber,
20 stretch sheet manufacturing apparatus, 21 transport roller group (arrangement section),
22 ultrasonic welding equipment (joining part forming part),
23 anvil roller, 24 horn roller,
25 discharge rollers,
26 cutter roller (cutting part), 261 cutter blade,
27 receiving roller (cutting part), 271 receiving blade,
30 upstream drive roller, 31 downstream drive roller,
32 a second upstream drive roller, 33 a second downstream drive roller,
40 transfer device, 41a to 41g holding unit,
42a-42f suction part, 43a-43f support part,
44 support drum, 44a suction hole,
50 supply roller, 51 discharge roller,
j junction, jP junction pair,

Claims (12)

A method for producing a stretchable sheet having a longitudinal direction and a lateral direction,
Arranging the thread rubber in the laterally extended state between the first sheet portion and the second sheet portion;
Forming a plurality of joints for joining the first sheet portion and the second sheet portion by crimping;
A step of relaxing the stretched state of the rubber thread;
After the relaxing step, cutting the thread rubber at the cutting position in the lateral direction,
The plurality of joints has a joint pair located on both sides of the rubber thread in the longitudinal direction,
After the cutting step, the contracted thread rubber is sandwiched between the joining portion pairs, and the lateral position of the thread rubber is regulated,
In the relaxing step, in the lateral direction, at least a portion on one side from the cutting position, and at least a portion on the other side from the cutting position, relax the stretched state of the thread rubber, Method for producing a stretchable sheet. It is a manufacturing method of the elastic sheet of Claim 1, Comprising:
In the relaxing step, the thread rubber is relaxed so as to be in a state between the stretched state and the natural state. It is a manufacturing method of the elastic sheet of Claim 2, Comprising:
When the elongation magnification of the rubber thread in the stretched state is R1, the elongation magnification of the rubber thread relaxed in the relaxing step is R2, and the elongation magnification of the rubber thread in a natural state is R3, R2 is represented by the following formula: R2> R3 + (R1-R3) / 2
A method for producing a stretchable sheet, characterized by satisfying the following. It is a manufacturing method of the elastic sheet according to any one of claims 1 to 3,
The upstream drive roller supplies a laminate in which the thread rubber is disposed between the first sheet portion and the second sheet portion to a thread rubber cutting device,
The downstream drive roller discharges the laminate from the cutting device,
A method for manufacturing a stretchable sheet, wherein the peripheral speed of the upstream drive roller is higher than the peripheral speed of the downstream drive roller. It is a manufacturing method of the elastic sheet of Claim 4, Comprising:
A second upstream drive roller between the upstream drive roller and the cutting device supplies the laminate to the cutting device,
A second downstream drive roller between the downstream drive roller and the cutting device discharges the laminate from the cutting device,
The peripheral speed of the second upstream drive roller is lower than the peripheral speed of the upstream drive roller,
The peripheral speed of the second downstream drive roller is higher than the peripheral speed of the second upstream drive roller, and the peripheral speed of the second downstream drive roller is higher than the peripheral speed of the downstream drive roller. Method for producing a functional sheet. It is a manufacturing method of the elastic sheet of Claim 4, Comprising:
The cutting device has a cutter roller having a cutter blade, and a receiving roller disposed to face the cutter roller,
The peripheral speed of the cutter roller is higher than the peripheral speed of the upstream drive roller. It is a manufacturing method of the elastic sheet of Claim 4, Comprising:
A method for manufacturing a stretchable sheet, wherein a cutter blade of the cutting device cuts the laminate by pushing down the laminate in a thickness direction thereof. It is a manufacturing method of the elastic sheet according to any one of claims 1 to 3,
Cutting the thread rubber while transporting the laminate in which the thread rubber is disposed between the first sheet portion and the second sheet portion by a transport device,
The transport device has a plurality of holding units that partially hold the laminate at intervals in the transport direction of the laminate,
A method for manufacturing a stretchable sheet, comprising cutting the thread rubber located between the holding portions after narrowing the interval between the holding portions. It is a manufacturing method of the elastic sheet according to any one of claims 1 to 3,
Cutting the thread rubber while transporting the laminate in which the thread rubber is disposed between the first sheet portion and the second sheet portion by a transport device,
The supply roller supplies the stacked body to the transfer device,
The supply speed of the laminate by the supply roller is higher than the transport speed of the laminate by the transport device,
The transport device has a plurality of holding units that partially hold the laminate at intervals in the transport direction of the laminate,
A method for manufacturing a stretchable sheet, comprising cutting the thread rubber located between the holding portions after widening the interval between the holding portions. It is a manufacturing method of the elastic sheet according to any one of claims 1 to 3,
Cutting the thread rubber while transporting the laminate in which the thread rubber is disposed between the first sheet portion and the second sheet portion by a transport device,
The transport device has a suction unit that partially sucks the laminate and a support unit that partially supports the laminate, and has a support unit that is alternately arranged in the transport direction of the laminate,
A method for manufacturing a stretchable sheet, comprising: cutting the thread rubber located on the suction unit after narrowing the interval between the suction units in the transport direction. It is a manufacturing method of the elastic sheet according to any one of claims 1 to 10,
The method of manufacturing a stretchable sheet according to claim 1, wherein an interval between the pair of joints in the longitudinal direction is equal to or larger than a diameter of the thread rubber in the extended state. An apparatus for manufacturing a stretchable sheet having a vertical direction and a horizontal direction,
An arranging portion for arranging the thread rubber in the laterally extended state between the first sheet portion and the second sheet portion;
A joining portion forming portion that forms a plurality of joining portions that press-fit the first sheet portion and the second sheet portion to join each other;
A relaxing portion for relaxing the stretched state of the rubber thread;
After the step of relaxing, a cutting section for cutting the thread rubber at the cutting position in the lateral direction,
The plurality of joints has a joint pair located on both sides of the rubber thread in the longitudinal direction,
After the rubber thread has been cut, the contracted rubber thread is sandwiched between the joints, and the lateral position of the rubber thread is regulated,
The relief portion relaxes the stretched state of the rubber thread in at least a portion on one side from the cutting position and at least a portion on the other side from the cutting position in the lateral direction. Equipment for manufacturing stretchable sheets.

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