Manufacturing equipment for composite elastic members

Abstract

Provided is a composite stretchable member manufacturing apparatus which can improve a breaking preventive function by reducing defects of elastic members coming off from grooves of a conveyance roller. A composite stretchable member manufacturing apparatus (100) is for manufacturing a composite stretchable member in which two sheets (2a, 2b) and a plurality of elastic members (10) are bonded together. The manufacturing apparatus (100) is provided with a guiding device (110) for guiding the two sheets (2a, 2b) and the elastic members (10) toward a bonding device (200). The guiding device (110) is provided with a guide member (112) for guiding the elastic members (10) toward a plurality of grooves (214) in the outer circumferential surface of a conveyance roller (210) of the bonding device (200). The tip end (114a) of the guide member (112) has formed therein a plurality of guide grooves (114b) for retaining the elastic members (10). The guide member (112) is disposed such that a length (L1) of each of the elastic members (10) positioned between the corresponding guide groove (114b) and the corresponding groove (214) of the conveyance roller (210) is 30 mm or less.

Description

[Technical Field]

[0001] The present invention relates to a manufacturing apparatus for manufacturing composite elastic members. [Background technology]

[0002] BACKGROUND ART Wearing articles such as disposable diapers having a waist portion and a crotch portion are known. In some cases, the waist portion of the wearing article is made of a stretchable composite elastic member to improve comfort.

[0003] An example of an apparatus for manufacturing a composite elastic member is disclosed in Patent Document 1.

[0004] In the device described in Patent Document 1, an elastic, stretchable member is sandwiched between two sheets made of nonwoven fabric or the like, and the two sheets and the elastic, stretchable member are fed between an ultrasonic welding horn and an anvil roll for conveying the sheets to perform the welding process.

[0005] A seal pattern protrusion is formed on the outer periphery of the anvil roll, and welded portions are formed on the two sheets corresponding to the seal pattern protrusion. The seal pattern protrusion also has a groove formed therein corresponding to the portion where the elastically stretchable member is to be placed. The depth of the groove is set so that when the elastically stretchable member is inserted into the groove, a portion of the elastically stretchable member protrudes from the groove.

[0006] By inserting a portion of the elastically stretchable member into this groove, the pressure applied to the elastically stretchable member is alleviated when the two sheets and the elastically stretchable member are sandwiched between the ultrasonic welding horn and the protruding seal pattern of the anvil roll for ultrasonic welding, making it possible to weld the two sheets and the elastically stretchable member without cutting them.

[0007] Therefore, in order to weld the elastically stretchable member to the two sheets without cutting it, it is necessary to prevent the elastically stretchable member from coming out of the grooves in the convex parts of the seal pattern. For this reason, the device described in Patent Document 1 is provided with a guide member on the upstream side of the anvil roll in the direction in which the elastically stretchable member is supplied to the anvil roll. The guide member is positioned away from the outer peripheral surface of the anvil roll and guides the elastically stretchable member into the grooves in the convex parts of the seal pattern on the anvil roll.

[0008] In the device of Patent Document 1, a guide member guides the elastically stretchable member into the grooves of the seal pattern convex parts on the anvil roll, but the elastically stretchable member can come out of the groove due to factors such as vibration of the device, and there is a need to reduce the problem of the elastically stretchable member coming out of the groove and improve the breakage prevention function. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] International Publication No. 2016 / 208502 Summary of the Invention

[0010] An object of the present invention is to provide a manufacturing apparatus for a composite elastic member that can reduce the problem of the elastic member coming out of the groove of the conveying roller and improve the breakage prevention function.

[0011] In order to solve the above-mentioned problems, the present invention provides a composite elastic member manufacturing apparatus for manufacturing a composite elastic member having two sheets and a plurality of elastic members sandwiched between them, by conveying two sheets along their longitudinal direction and bonding the sheets together and the sheets together with a plurality of elastic members, the apparatus comprising: a joining device that welds and bonds each elastic member to the sheets and the two sheets together with each other while sandwiching each elastic member between the two sheets being conveyed; and a guide device that guides the two sheets and each elastic member to the joining device so that each elastic member extends in the longitudinal direction and is sandwiched between the two sheets, the joining device comprising: a conveying roller that has an outer peripheral surface that conveys the two sheets with the sandwiched elastic members in the longitudinal direction of the sheets and rotates around a predetermined axis; and a clamping device that clamps the two sheets with the elastic members sandwiched between the outer peripheral surfaces of the conveying rollers, and is configured to apply heat to the sheets between the conveying rollers and the clamping device, wherein the outer peripheral surface of the conveying roller is formed with at least one convex portion that protrudes radially outward from the outer peripheral surface, and the convex portion has a plurality of grooves that extend in the conveying direction of the conveying roller and are spaced apart in a direction parallel to the axis, and the guide device includes a guide member having a tip that is closest to the outer peripheral surface of the conveying roller and a plurality of guide grooves that are provided at the tip and hold the plurality of elastic members in a state where they are spaced apart in a direction parallel to the axis of the conveying roller so as to guide the plurality of elastic members into the plurality of grooves of the conveying roller, respectively, and the guide member is arranged so that the length of the elastic members located between the guide groove and the groove of the conveying roller is 30 mm or less. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a plan view of a composite elastic member manufactured by a manufacturing apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a partial cross-sectional view taken along line II-II in FIG. [Figure 3]FIG. 3 is a schematic cross-sectional view showing a cross section of an elastic member. [Figure 4] FIG. 2 is a diagram corresponding to FIG. 1 and schematically showing a joint portion. [Figure 5] FIG. 2 is an enlarged view of a part of FIG. [Figure 6] 1 is a schematic explanatory diagram showing the configuration of a manufacturing apparatus for a composite elastic member according to an embodiment of the present invention. [Figure 7] FIG. 7 is a plan view of the guide plate of FIG. 6. [Figure 8] FIG. 8 is a side view of the guide plate of FIG. 7. [Figure 9] 8 is an enlarged view of a guide groove of the guide plate of FIG. 7. [Figure 10] 7(a) is an enlarged view of the guide plate and its surrounding area of ​​the manufacturing apparatus of FIG. 6, and FIG. 7(b) is an enlarged view of the portion where the elastic member is fed from the guide groove of the guide plate of FIG. [Figure 11] FIG. 7 is a view showing the outer peripheral surface of the anvil roll of FIG. 6. [Figure 12] 12 is an enlarged view of the protrusions and grooves on the outer peripheral surface of the anvil roll of FIG. 11. FIG. [Figure 13] 13 is a cross-sectional view taken along line XIII-XIII in FIG. 12. [Figure 14] FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG. 12. [Figure 15] FIG. 1 is a development view of a disposable diaper using a composite elastic member. [Figure 16] 16A to 16C are diagrams each schematically showing stages 1 to 3 for explaining the manufacturing method of the disposable diaper shown in FIG. 15. [Figure 17] This figure shows a manufacturing apparatus according to a modified example of the present invention, in which the guide plate is movable between a position close to the anvil roll and a position away from the anvil roll, and shows the state in which the guide plate is in a position close to the anvil roll (the position in which the manufacturing apparatus is in operation). [Figure 18] 18 is a diagram showing a state in which the guide plate in FIG. 17 is in a position away from the anvil roll (a position at which an elastic member (such as rubber thread) is passed through). FIG. DETAILED DESCRIPTION OF THE INVENTION

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following describes embodiments of the present invention with reference to the accompanying drawings. Note that the following embodiments are examples that embody the present invention and are not intended to limit the technical scope of the present invention.

[0014] (1) Structure of the composite elastic member Fig. 1 is a plan view of a composite elastic member manufactured by a manufacturing apparatus according to an embodiment of the present invention, and Fig. 2 is a partial cross-sectional view taken along line II-II in Fig. 1.

[0015] The composite elastic member 1 comprises two long sheets 2a, 2b facing each other, and a plurality of long elastic members 10 that are stretchable in the longitudinal direction A. Each elastic member 10 is disposed between the sheets 2a, 2b so as to be stretchable in the longitudinal direction A (left-right direction in FIG. 1) of each sheet 2a, 2b, i.e., so as to extend along the longitudinal direction A of each sheet 2a, 2b so as to be stretchable in the longitudinal direction A of each sheet 2a, 2b. In this embodiment, these elastic members 10 are disposed at equal intervals from each other in the width direction B of the sheets 2a, 2b (a direction perpendicular to the longitudinal direction A of the sheets 2a, 2b), and extend parallel to the longitudinal direction A of the sheets 2a, 2b.

[0016] In this embodiment, sheet-like materials such as nonwoven fabrics are used as both sheets 2a and 2b.

[0017] The elastic member 10 is made of a material that is more stretchable than the material (such as a nonwoven fabric) of the sheets 2a, 2b, and the present invention does not particularly limit the material of the elastic member 10. For example, in this embodiment, as shown in Fig. 3, the elastic member 10 is a multi-strand in which a plurality of rubber threads (fibrous elastic bodies) 10a are gathered in a bundle, and at least some of the rubber threads 10a are covered with a covering layer 10b. Specifically, the rubber threads 10a arranged particularly on the outer periphery of the plurality of rubber threads 10a are covered with the covering layer 10b. Note that all of the rubber threads 10a may be covered with the covering layer 10b.

[0018] The rubber thread 10a may be made of polyurethane, for example, and the covering layer 10b may be made of a lubricant such as silicone oil or magnesium stearate, for example.

[0019] As shown in FIG. 1, the sheets 2a and 2b are joined together, and the sheets 2a and 2b are joined to the elastic member 10 at lattice-shaped joints 4. As shown in FIG.

[0020] Figure 4 is a schematic diagram of the joint shown in Figure 1. As shown in Figures 1 and 4, the joint 4 has a plurality of first joints 4a and a plurality of second joints 4b.

[0021] The first joint portions 4a are arranged at equal intervals in the longitudinal direction A of the sheets 2a and 2b, and extend parallel to each other in the width direction B of the sheets 2a and 2b.

[0022] The second joints 4b are also arranged at equal intervals in the longitudinal direction A of the sheets 2a, 2b, and extend parallel to each other toward the width direction B of the sheets 2a, 2b. The second joints 4b extend so as to intersect with the first joints 4a, thereby forming a lattice-shaped joint 4.

[0023] In this embodiment, both the first and second joint portions 4a and 4b are inclined with respect to the width direction B of the sheets 2a and 2b. The inclination angle is set to be less than 45 degrees. For example, the inclination angle is set to be 30 degrees.

[0024] The first and second joints 4a and 4b are symmetrical with respect to both lines extending in the longitudinal direction A and width direction B of the sheets 2a and 2b. The first and second joints 4a and 4b are arranged so that the distance between adjacent first joints 4a is the same as the distance between adjacent second joints 4b. Accordingly, the joints 4 define multiple diamonds whose diagonals extend along the longitudinal direction A and width direction B of the sheets 2a and 2b. In particular, as described above, the first and second joints 4a and 4b are inclined at angles of less than 45 degrees with respect to the width direction B of the sheets 2a and 2b, resulting in diamonds extending in the width direction B. The intersections 4c between the first joint 4a and the second joint 4b (hereinafter sometimes referred to as joint-side intersections) are arranged at equal intervals on a straight line extending in the longitudinal direction A of the sheets 2a, 2b, and are also arranged at equal intervals on a straight line extending in the width direction B of the sheets 2a, 2b.

[0025] Each joint 4 intersects all of the elastic members 10 and extends along a line intersecting the stretch direction (i.e., the longitudinal direction A) of the elastic members 10. Specifically, each joint 4 extends between both outer portions of the sheets 2a, 2b in the width direction B beyond the area where the elastic members 10 are arranged.

[0026] Each elastic member 10 and the joint 4 intersect at a position other than the joint side intersection 4c, i.e., at a position spaced apart from the joint side intersection 4c, and each elastic member 10 and each sheet 2a, 2b are joined at this position.

[0027] A specific description will be given with reference to FIG. 5, which shows an enlarged view of a part of FIG.

[0028] Each elastic member 10 is disposed so as to pass between two adjacent joint-side intersections 4c on each first joint 4a (for example, between the joint-side intersections 4c_1 and 4c_2 and between the joint-side intersections 4c_2 and 4c_3 shown in FIG. 5). That is, a first elastic member-side intersection 4d, which is the intersection between each elastic member 10 and each first joint 4a, is located between two adjacent joint-side intersections 4c on the first joint 4a, and the elastic member 10 and the sheets 2a, 2b are joined at this position 4d.

[0029] Similarly, each elastic member 10 is arranged to pass between adjacent joint-side intersections 4c on each second joint 4b (for example, between joint-side intersections 4c_4 and 4c_2 and between joint-side intersections 4c_2 and 4c_5 shown in FIG. 5). That is, second elastic member-side intersections 4e, which are intersections between each elastic member 10 and each second joint 4b, are located between two adjacent joint-side intersections 4c on the second joint 4b, and the elastic member 10 and the sheets 2a, 2b are joined at this position 4e.

[0030] In this embodiment, each elastic member 10 passes through the center of adjacent joint-side intersections 4c, 4c on each first joint 4a and the center of adjacent joint-side intersections 4c, 4c on each second joint 4b, and intersects with the first joint 4a and the second joint 4b at these center positions to be joined to each sheet 2a, 2b.

[0031] Accordingly, the first elastic member side intersections 4d and the second elastic member side intersections 4e are alternately arranged on a straight line extending in the width direction B of both sheets 2a, 2b. Furthermore, the intersections of each elastic member 10 and the joint 4, i.e., the joints 4d, 4e between the elastic members 10 and sheets 2a, 2b, are arranged at equal intervals in the longitudinal direction A of the sheets 2a, 2b.

[0032] At the joints 4, the sheets 2a and 2b are joined to each other, and the sheets 2a and 2b and the elastic member 10 are joined to each other by welding. In this embodiment, these are joined by ultrasonic welding.

[0033] The sheets 2a and 2b are joined together by partially melting and welding them together, while the elastic member 10 and the sheets 2a and 2b are welded together by partially melting the sheets 2a and 2b and melting the coating layer 10b of the elastic member 10.

[0034] Specifically, in this embodiment, a rubber thread having a melting point of approximately 200°C is used as the rubber thread 10a, and magnesium stearate (melting point: approximately 120°C), which has a lower melting point, is used as the coating layer 10b. When the elastic member 10 and the sheets 2a and 2b are welded together, the coating layer 10b melts without melting the rubber thread 10a, and the coating layer 10b and the sheets 2a and 2b are welded together.

[0035] (2) Manufacturing equipment for composite elastic members Next, a manufacturing apparatus for manufacturing the composite elastic member 1 will be described.

[0036] FIG. 6 is a schematic diagram of a manufacturing apparatus 100 according to an embodiment of the present invention.

[0037] The manufacturing apparatus 100 includes a joining device 200 that sandwiches the elastic member 10 between the sheets 2a and 2b and ultrasonically welds the elastic member 10 to the sheets 2a and 2b, and the sheets 2a and 2b to each other, a first guide roller 102 that guides the sheet 2a to the joining device 200 (specifically, the anvil roll 210 described below), an elastic member guiding device (guiding device) 110 that supplies the elastic member 10 to the joining device 200, a nip roll (second guide roller) 104 that guides the sheet 2b to the joining device 200 and presses down the two sheets 2a and 2b and the elastic member 10, and a third guide roller 106 that guides the joined sheets, i.e., the composite elastic member 1.

[0038] The bonding device 200 includes an anvil roll (transport roller) 210 and a horn (pressure device) 220.

[0039] The anvil roll 210 is a rotating member that rotates around an axis extending perpendicular to the plane of the paper in FIG. 6. Hereinafter, the direction perpendicular to the plane of the paper in FIG. 6 will be referred to as the "front-rear direction." The anvil roll 210 is rotatably attached to a vertical wall portion of the device, such as a head plate (not shown), with a horizontally extending axis as the center of rotation. As the anvil roll 210 rotates, it conveys the elastic member 10 guided by the elastic member guiding device 110, sandwiched between the sheets 2a and 2b guided by the rollers 102 and 104 on its outer circumferential surface. In the example shown in FIG. 6, the anvil roll 210 rotates counterclockwise in FIG. 6. Hereinafter, the sheets 2a and 2b sandwiching the elastic member 10 may be referred to as the "pre-bonding sheets."

[0040] As shown in Fig. 11, the outer peripheral surface of the anvil roll 210 is formed with protrusions 212 that protrude radially outward from the outer peripheral surface. The protrusions 212 are provided on the outer peripheral surface of the anvil roll 210 over the entire circumferential direction. The protrusions 212 have a shape that corresponds to the joints 4. In this embodiment, as described above, the joints 4 have a diamond-shaped lattice pattern, and the protrusions 212 also have a diamond-shaped lattice pattern that corresponds to this.

[0041] Specifically, the protrusion 212 includes a first protrusion 212a for forming the first bonding portion 4a and a second protrusion 212b for forming the second bonding portion 4b.

[0042] The first protrusions 212a extend in a direction (first direction C1) that intersects with the circumferential direction of the anvil roll 210 (the conveying direction of the anvil roll 210), i.e., along a line that intersects with this circumferential direction, and are arranged parallel to each other and at equal intervals in the circumferential direction. The second protrusions 212b extend in a direction (second direction C2) that intersects with the circumferential direction and first direction C1 of the anvil roll 210, i.e., along a line that intersects with this circumferential direction, and are arranged parallel to each other and at equal intervals in the circumferential direction of the anvil roll 210.

[0043] Each first convex portion 212a and second convex portion 212b is inclined symmetrically at an angle of less than 45 degrees relative to the front-to-rear direction, and the distance between two adjacent first convex portions 212a is the same as the distance between two adjacent second convex portions 212b, and the intersections 212c of the first convex portions 212a and second convex portions 212b are arranged at equal intervals on a line extending in the front-to-rear direction and the circumferential direction of the anvil roll 210.

[0044] 12, which is an enlarged view of a portion of FIG. 11, FIG. 13, which is a cross-sectional view taken along line XIII-XIII of FIG. 12, and FIG. 14, which is a cross-sectional view taken along line XIV-XIV of FIG. 12, the first convex portion 212a and the second convex portion 212b are each formed with grooves 214 (214a, 214b) that are recessed radially inward of the anvil roll 210. As shown in FIG. 13 and other figures, the first convex portion 212a and the second convex portion 212b are each formed with a plurality of grooves 214 at positions spaced apart in the longitudinal directions C1 and C2 thereof.

[0045] The portions of the sheet 2a (the sheet disposed on the anvil roll 210 side) on which the elastic members 10 are disposed are inserted into the inside of these grooves 214. Therefore, the arrangement of the elastic members 10 relative to the joint portions 4 and the arrangement of the grooves relative to the protrusions 212 are the same.

[0046] 12, in the present embodiment, grooves (first grooves) 214a extending in the circumferential direction of the anvil roll 210 are formed in the portions of each first protrusion 212a between the intersections 212c with the second protrusion 212b, more specifically, in the centers of adjacent intersections 212c. In addition, grooves (second grooves) 214b are formed in the portions of each second protrusion 212b between the intersections 212c with the first protrusion 212a, more specifically, in the centers of adjacent intersections 212c. These grooves 214 are provided at equal intervals on a line extending in the circumferential direction of the anvil roll 210 and on a line extending in the front-rear direction (i.e., in a direction parallel to the rotation axis of the anvil roll 210, in other words, in the same direction as the extension of the rotation axis).

[0047] The portions of the sheet 2a where the elastic members 10 are arranged are inserted into the grooves 214 and transported by the anvil roll 210. As described above, in this embodiment, the elastic members 10 are guided into the grooves 214 by the guide plate 112, which has guide grooves 114b provided at positions corresponding to the grooves 214, and therefore the elastic members 10 are stably arranged in appropriate positions on the sheet 2a.

[0048] In this embodiment, in addition to the sheet 2a, a part of the elastic member 10 is inserted into these grooves 214 and transported by the anvil roller 210. Note that the sheet 2a may be transported with only the sheet 2a inserted.

[0049] In this way, the grooves 214 are formed in the portions of the protrusions 212 where the elastic members 10 are arranged, so that when the pre-bonding sheets are clamped during bonding, at least a portion of the elastic members 10 arranged on the pre-bonding sheets is retracted into the grooves, thereby preventing the elastic members 10 from being cut when clamped.

[0050] However, if the cross-sectional area of ​​the groove 214 is too large, it may be difficult to properly bond the elastic member 10 and the sheets 2a and 2b. Therefore, in this embodiment, as shown in Fig. 14, when the elastic member 10 at its natural length is placed in the groove 214, a part of the elastic member 10 protrudes outward from the groove 214, and the rest of the elastic member 10 is accommodated in the groove 214. In detail, the shape of a cross section obtained by cutting the groove 214 on a plane perpendicular to the circumferential direction (conveyance direction) of the anvil roll 210 is set to a shape such that, when the elastic member 10 is placed in the groove 214 at its natural length, a part of the elastic member 10 protrudes outward in the radial direction of the anvil roll 210 from a straight imaginary line L10 connecting the open ends (Q1, Q2) of the groove 214. Furthermore, the cross-sectional shape of the groove 214 is set so that when the elastic member 10 is placed in the groove 214 in a state stretched from its natural state (e.g., stretched by 300%), a portion of the elastic member 10 protrudes outward in the radial direction of the anvil roll 210 from a straight imaginary line L10 connecting the open ends (Q1, Q2) of the groove 214. The cross-sectional shape of such a groove 214 is preferably a substantially V-shape, as shown in FIG. 14. Furthermore, the cross-sectional area S1 of such a groove 214 is preferably smaller than the cross-sectional area of ​​the elastic member 10 to be placed therein. The cross-sectional shape of the groove 214 is not limited to a V-shape, and may be a U-shape or other shape.

[0051] By forming the cross-sectional shape of the groove 214 so that a portion of the elastic member 10 protrudes from the groove 214, the elastic member 10 can be retracted into the groove 214 during ultrasonic welding, while applying appropriate pressure to the elastic member 10 placed in the groove and the sheets 2a and 2b to bond them together. This allows the sheets 2a and 2b to be more reliably bonded to the elastic member 10 while suppressing damage to the elastic member 10. Specifically, while applying appropriate pressure to the portion of the elastic member 10 that protrudes beyond the imaginary line L10 connecting the opening ends Q1 and Q2 of the groove 214 and the sheets 2a and 2b, the portion of the elastic member 10 inside the imaginary line L10, i.e., the portion housed within the groove 214, can be retracted to the inside of the groove 214 (the side away from the horn 220). This allows the bonding strength between the elastic member 10 and the sheets 2a and 2b to be secured while suppressing damage to the elastic member 10.

[0052] In particular, if the cross-sectional shape of the groove 214 is set so that when the elastic member 10 is placed in the groove 214 in a state stretched 300%, a portion of the elastic member 10 extends radially outward of the anvil roll 210 beyond the straight imaginary line L10 connecting the opening ends (Q1, Q2) of the groove 214, it is possible to apply more appropriate pressure to the sheets 2a, 2b and the elastic member 10 and more reliably join them to each other while suppressing damage to the elastic member 10.

[0053] The horn 220 shown in Fig. 6 and Fig. 10(a) is a device that applies ultrasonic vibrations to the pre-bonding sheet being transported by the anvil roll 210 while sandwiching (applying pressure while sandwiching) the pre-bonding sheet between the anvil roll 210 and the outer peripheral surface of the anvil roll 210. The horn 220 is disposed opposite the outer peripheral surface of the anvil roll 210. In the example of Fig. 6, the horn 220 is disposed opposite an upper portion of the outer peripheral surface of the anvil roll 210. An output unit 221 that applies ultrasonic vibrations toward the outer peripheral surface of the anvil roll 210 is provided at the tip of the horn 220.

[0054] The horn 220 applies ultrasonic vibrations to the pre-bonding sheets while pressing the output portion 221 against the pre-bonding sheets and clamping the pre-bonding sheets between the anvil roll 210. As a result, the sheets 2a and 2b melt and are welded to each other. The elastic member 10 also melts and is welded to the elastic member 10 and the sheets 2a and 2b. Specifically, the output portion 221 clamps the pre-bonding sheets between the protrusions 212 and bonds the sheets 2a and 2b to each other and the elastic member 10 to the sheets 2a and 2b to each other at the portions of the pre-bonding sheets that are located on the protrusions 212. The tip of the output portion 221 has a flat shape (see FIGS. 13 and 14).

[0055] As described above, in this embodiment, magnesium stearate, which has a lower melting point than the rubber thread 10a, is used for the coating layer 10b, so that when the elastic member 10 and the sheets 2a and 2b are welded together, the coating layer 10b melts without melting the rubber thread 10a, thereby welding the coating layer 10b to the sheets 2a and 2b.

[0056] An output portion 221 at the tip of the horn 220 extends in the front-rear direction, and the horn 220 applies ultrasonic vibrations to the outer peripheral surface of the anvil roll 210 over the entire direction of the rotation axis of the anvil roll 210. While the pre-bonding sheets are being transported by the anvil roll 210, the horn 220 is constantly applying ultrasonic vibrations. Therefore, as the pre-bonding sheets are transported by the anvil roll 210, the pre-bonding sheets are continuously bonded.

[0057] 6, in this embodiment, the sheet 2a is guided by the first guide roller 102 to a position on the outer circumferential surface of the anvil roll 210 that is away from the horn 220 on the upstream side. As the anvil roll 210 rotates, the sheet 2a is transported along the outer circumferential surface of the anvil roll 210 toward the horn 220.

[0058] The sheet 2b is introduced by the nip roll 104 into a portion of the outer circumferential surface of the anvil roll 210 that is near the horn 220 and is upstream of the horn 220 in the conveying direction.

[0059] The elastic member 10 is introduced by the elastic member guiding device 110 onto the outer peripheral surface of the anvil roll 210 at a position between the position where the sheet 2a is introduced onto the anvil roll 210 and the position where the sheet 2b is introduced onto the anvil roll 210. As a result, the elastic member 10 is transported to a position facing the horn 220 while being sandwiched between the sheets 2a and 2b.

[0060] The position where the sheet 2b is introduced from the nip roll 104 to the anvil roll 210 may be anywhere between the position where the elastic member 10 is introduced and the position facing the horn 220, but is preferably closer to the position facing the horn 220, and more preferably close to the position facing the horn 220. In this embodiment, as shown in FIGS. 6 and 10(a), the nip roll 104 is disposed immediately upstream of the horn 220 in the conveyance direction of the sheets 2a and 2b (i.e., the rotation direction of the anvil roll 210 (counterclockwise in FIG. 10(a))). In this case, it is possible to prevent the elastic member 10 introduced onto the outer peripheral surface of the anvil roll 210 from being displaced by being covered by the sheet 2b early.

[0061] The elastic members 10 are introduced onto the outer peripheral surface of the anvil roll 210 in a state where they are lined up parallel to each other in the front-to-rear direction, and are placed on the outer peripheral surface of the anvil roll 210 on top of the sheet 2a that was previously introduced onto the outer peripheral surface of the anvil roll 210 in a state where they are parallel to each other in the width direction B. The elastic members 10 are introduced onto the anvil roll 210 in a state where they are stretched in the circumferential direction of the anvil roll 210. In this embodiment, the elastic members 10 are introduced onto the anvil roll 210 in a state where they are stretched to 300% of their natural state (the natural state is defined as 100%).

[0062] Next, the elastic member guide device 110 (particularly the guide plate 112) of this embodiment will be described in detail.

[0063] As shown in FIGS. 6 and 10, the elastic member guiding device 110 has a plurality of guide rolls 111 and a plate-shaped guide plate 112 serving as a guide member.

[0064] The guide rolls 111 are rotating members that can rotate around axes that extend in the front-rear direction, and guide the elastic member 10 toward the anvil roll 210 in a stretched state (for example, a state stretched by 300%).

[0065] As shown in Figures 6 to 10, the guide plate 112 is a flat member that guides each elastic member 10 into multiple grooves 214 (see Figures 11 to 14) formed on the outer peripheral surface of the anvil roll 210 while keeping them spaced apart from each other in the front-to-rear direction (i.e., the direction parallel to the axis of the anvil roll 210).

[0066] The guide plate 112 has a tip 114a which is the edge closest to the outer circumferential surface of the anvil roll 210, and a base end which is positioned further away from the anvil roll 210 than the tip 114a, and is disposed so as to extend in a direction toward and away from the anvil roll 210 and also in the front-to-rear direction. In this embodiment, the thickness t of the guide plate 112 (the dimension in the vertical direction shown in FIG. 8) is set small so that the guide plate 112 does not interfere with the sheets 2a, 2b, and the guide plate 112 has a thin plate shape.

[0067] The leading end 114a of the guide plate 112 has a tapered shape. Specifically, as shown in Fig. 8, the leading end portion (the portion on the anvil roll 210 side) of the guide plate 112 has an inclined surface 114c that is inclined so as to approach a bottom surface 114d of the guide plate 112 as it approaches the leading end 114a. The inclined surface 114c and the bottom surface 114d form the tapered leading end 114a. In this embodiment, the angle θ2 formed between the inclined surface 114c and the bottom surface 114d is set to about 10 degrees.

[0068] 10(a) and (b), the tip 114a of the guide plate 112 is located upstream (to the right in FIG. 10) of a contact point P2 on the outer circumferential surface of the anvil roll 210 where the elastic member 10 comes into contact, in the rotation direction of the anvil roll 210 (counterclockwise in FIG. 10), and faces the upstream side. The guide plate 112 is fixed in a stationary state at a predetermined position facing the outer circumferential surface of the anvil roll 210. In FIGS. 10(a) and (b), the guide plate 112 is fixed immovably by a fixing member 113, which is fixed to a panel or the like inside the apparatus, using screws or the like.

[0069] A plurality of guide grooves 114b are formed in the tapered tip 114a of the guide plate 112. Specifically, the plurality of guide grooves 114b are formed at positions equally spaced from one another in the front-to-rear direction (a direction parallel to the axis of the anvil roll 210) at the tip 114a of the guide plate 112, and individually hold the plurality of elastic members 10 so as to guide the elastic members 10 into the plurality of grooves 214 of the anvil roll 210. As shown in FIG. 9, which shows an enlarged portion of the guide grooves 114b in FIG. 7, these guide grooves 114b are recessed from the tip 114a of the inclined surface 114c toward the base end, and have a V-shape with an opening angle of 90 degrees. Note that the cross-sectional shape of the guide grooves 114b is not limited to a V-shape and may be other shapes such as a U-shape. These guide grooves 114b reliably position and hold each elastic member 10 in order to guide each elastic member 10 while keeping them spaced apart from one another in the front-to-rear direction on the outer circumferential surface of the anvil roll 210. These guide grooves 114b are provided opposite the grooves 214 formed in the anvil roll 210 and at the same intervals as the grooves 214, and guide the elastic members 10 into these grooves 214, respectively.

[0070] The tip 114a of the guide plate 112 and the guide groove 114b formed in the tip 114a face in the opposite direction (i.e., clockwise) to the rotation direction (counterclockwise in FIGS. 6 and 10(a)) of the anvil roll 210. Therefore, the elastic member 10 engaged with the guide groove 114b is pulled by the anvil roll 210 rotating counterclockwise, bent at the bottom P1 of the guide groove 114b, extends in the tangential direction of a contact point P2 on the outer circumferential surface of the anvil roll 210, and is inserted into the groove 214 (see FIGS. 11 to 14) on the outer circumferential surface of the anvil roll 210 at the contact point P2.

[0071] As shown in Figures 10(a) and (b), it is believed that the shorter the length L1 of the elastic member 10 positioned between the guide groove 114b and the groove 214 of the anvil roll 210 of the guide plate 112 (specifically, the distance L1 from the bottom P1 of the guide groove 114b to the contact point P2 where the elastic member 10 contacts the anvil roll 210), the less likely the elastic member 10 will come off the groove 214 of the anvil roll 210.

[0072] The inventors conducted an experiment to investigate the correlation between the length L1 of the elastic member 10 positioned between the guide groove 114b and the groove 214 of the anvil roll 210 (i.e., the free distance L1 that the elastic member 10 moves in the air without being restrained) and the probability of the elastic member 10 vibrating, and found the correlation shown in Table 1 below. In the experiment, linear rubber thread having a diameter of 0.1 mm or more was used as the elastic member 10, and the frequency with which the rubber thread touched each other and the amount of vibration were observed in a certain period of time as the rubber thread was continuously inserted from the guide groove 114b of the guide plate 112 into the groove 214 of the anvil roll 210 in the manufacturing apparatus 100. The experimental results are shown in Table 1 below.

[0073] [Table 1]

[0074] According to the experimental results in Table 1, if the free distance L1 of the thread rubber is 15 mm or less, the probability that thread rubber with a diameter of 0.1 mm or more will vibrate is 0.08%, which shows that the vibration suppression effect of the thread rubber is good (double circle).

[0075] Furthermore, even when the free distance L1 is in the range of 15 mm or greater but is between 15 and 30 mm, the probability that the rubber thread will vibrate is 4.66%, which is within the allowable probability (5%), so it can be seen that the vibration suppression effect of the rubber thread is acceptable or satisfactory (triangle).

[0076] On the other hand, when the free distance L1 is in a range greater than 30 mm, for example, 30 to 50 mm, the probability that the rubber thread will vibrate is 10% or more, which is far above the allowable probability (5%), and therefore the vibration suppression effect of the rubber thread is deemed to be unacceptable (X).

[0077] Based on the above experimental results, in order to reduce the problem of elastic member 10, such as rubber thread, coming off the groove 214 of the anvil roll 210, the guide plate 112 of this embodiment is preferably arranged so that the length L1 of the elastic member 10 positioned between the guide groove 114b and the groove 214 of the anvil roll 210 is 30 mm or less (preferably 15 mm or less) (practically, in the range of 1 to 30 mm, preferably 1 to 15 mm). Note that this distance L1 is set to be greater than 0 so that the guide plate 112 does not come into contact with the anvil roll 210 (specifically, the sheet 2a wound around the outer peripheral surface of the anvil roll 210) (i.e., so that the distance is greater than the thickness of the sheet 2a).

[0078] As shown in Figure 10(b), the guide plate 112 is arranged so that the gap δ1 between the bottom P1 of the guide groove 114b and the outer peripheral surface of the convex portion 212 of the anvil roll 210 is 1 mm or less (preferably 0.3 mm or less) (practically, in the range of 0.1 mm to 1 mm, preferably in the range of 0.1 mm to 0.3 mm).

[0079] As shown in Figure 10(b), the guide plate 112 is positioned so that the bottom surface 114d facing the anvil roll 210 forms an angle θ1 of 30 degrees or less (in practice, in the range of 1 to 30 degrees) with respect to the tangent to the anvil roll 210 at the contact point P2 where the anvil roll 210 and the elastic member 10 meet.

[0080] 6 and 10(a), the guide rolls 111 are arranged upstream of the guide plate 112 in the conveying direction of the elastic members 10, and guide the elastic members 10 into the guide grooves 114b. The outer circumferential surface of each guide roll 111 has a plurality of grooves (not shown) spaced apart from each other in the direction in which the rotation axis of the guide roll 111 extends, in order to guide the elastic members 10 into the guide grooves 114b, respectively.

[0081] As shown in Figure 10(a), the guide roll 111A, which is located most downstream among the multiple guide rolls 111, is positioned so that the distance L2 from when the elastic member 10 leaves the guide roll 111 to when it is inserted into the guide groove 114b is 50 mm or more, so as to prevent any effects caused by uneven rotation and rattle of the guide roll 111A (for example, sagging of the elastic member 10).

[0082] 6 and 10(a), the nip roll 104 is disposed upstream of the horn 220. The nip roll 104 is capable of nipping the two sheets and the elastic member 10 in cooperation with the anvil roll 210 in the region where the elastic member 10 is inserted into the groove 214 of the anvil roll 210 (i.e., the section from the initial position P2 (see FIG. 10(b)) on the outer circumferential surface of the anvil roll 210 where the elastic member 10 is inserted into the groove 214 (i.e., the point of contact between the anvil roll 210 and the elastic member 10) to the output section 221 (see FIG. 10(a)) of the horn 220).

[0083] Furthermore, as shown in FIG. 10(a), in this embodiment, in order to reduce the problem of the elastic member 10 coming out of the groove 214 of the anvil roll 210 between the time the elastic member 10 comes into contact with the groove 214 and the time the elastic member 10 is squeezed by the horn 220, the conveying distance L3 from the time the elastic member 10 comes into contact with the groove 214 of the anvil roll 210 until the time the elastic member 10 is squeezed by the horn 220 is set to 150 mm or less (in practice, in the range of 1 to 150 mm).

[0084] The optimum value for the transport distance L3 was derived through experiments by the inventors. Specifically, as shown in Table 2 below, when a linear rubber thread having a diameter of 0.1 mm or more was used as the elastic member 10, the relationship between the transport distance L3 from when the rubber thread comes into contact with the groove 214 of the anvil roll 210 until it is compressed by the horn 220 and the probability of the rubber thread vibrating was investigated through experiments.

[0085] [Table 2]

[0086] According to the experimental results in Table 2, when the rubber thread conveying distance L3 is 150 mm, the probability of the rubber thread vibrating when the free distance L1 is 11 mm is 0.16%, and when the free distance L1 is 19 mm is 3.66%, both of which are within the allowable probability (5%), and the rubber thread vibration suppression effect is fully demonstrated (passed). Furthermore, when the conveying distance L3 is 20 mm, the probability of the rubber thread vibrating when the free distance L1 is 11 mm is 0.08%, and when the free distance L1 is 19 mm, the probability is reduced to 1.12%.

[0087] However, when the thread rubber conveying distance L3 is 300 mm, the probability that the thread rubber will vibrate when the above-mentioned free distance L1 is 11 mm is 5.73%, and the probability that the thread rubber will vibrate when the free distance L1 is 19 mm is 9.62%, which is far above the allowable probability (5%), and therefore it can be seen that the vibration suppression effect of the thread rubber is insufficient (fails).

[0088] From the experimental results in Table 2 above, it can be seen that in order to reduce the problem of the elastic member 10 coming out of the groove 214 of the anvil roll 210 between the time it comes into contact with the groove 214 and the time it is compressed by the horn 220, it is preferable to set the conveying distance L3 to 150 mm or less.

[0089] (3) Wearable articles and their manufacturing methods FIG. 15 is a schematic diagram showing a disposable diaper (wearing article) 20 in which the composite elastic member 1 constructed as above is used, as an example of use of the composite elastic member 1.

[0090] The disposable diaper 20 has a waist portion 21 having a front portion 21a to be placed in front of the wearer's abdomen and a rear portion 21b to be placed on the buttocks side of the wearer, and a crotch portion 22 to be placed between the wearer's legs. The composite stretchable member 1 of this embodiment is used in the front portion 21a and the rear portion 21b. For example, the composite stretchable member 1 is applied to the front portion 21a and the rear portion 21b so that the stretch direction of the composite stretchable member 1 coincides with the waist direction (left-right direction in FIG. 15) when worn.

[0091] FIG. 16 is a diagram showing an example of a manufacturing method for the disposable diaper 20, and the present invention is not limited to this. The manufacturing method shown in FIG. 16 is composed of stages 1 to 3. First, in stage 1, a pair of continuums 101 are prepared, each of which is made up of the composite elastic members 1 lined up in the conveying direction. That is, a continuum 101 for forming the front abdominal portion 21a and a continuum 101 for forming the back portion 21b are prepared. Then, the two continuums 101 are conveyed in the longitudinal direction of the continuums 101 while being arranged parallel to each other, and a crotch portion 22 is placed across both continuums 101 so that its longitudinal direction is perpendicular to the longitudinal direction of the continuum 101. For example, a plurality of crotch portions 22 are placed at intervals in the conveying direction. Then, the crotch portions 22 and the continuum 101 are joined to form a joined body. 103 (junction formation step).

[0092] Next, in stage 2, holes are opened between the adjacent crotch portions 22 to form leg openings. 103 The continuum 101 is folded in half along the center line CL1 in the width direction (the direction perpendicular to the longitudinal direction of the continuum 101) so that the crotch portion 22 is on the inside (folding step).

[0093] Next, in stage 3, the overlapping portions of the continuum 101 located in the middle of adjacent crotch portions 22 are joined along a direction perpendicular to the longitudinal direction of the continuum 101 to form side seals SS (side sealing process), and the continuum 101 is cut along the cutting line K in the side seal portion (cutting process).

[0094] In this manner, the disposable diaper 20 is manufactured, in which the waist portion 21 (the front abdominal portion 21a and the rear portion 21b) is made of the composite elastic member 1 and which is elastic in the waist direction.

[0095] In this embodiment, the step of opening holes that will become leg openings may or may not be performed before joining the crotch portion 22 to the continuum 101. Furthermore, each elastic member 10 of the composite elastic member 1 may be adhered to the two sheets 2a, 2b with a hot melt adhesive in the vicinity of the portion corresponding to the cutting line K. This prevents each elastic member 10 from coming loose when cutting along the cutting line K.

[0096] (Features of this embodiment) (1) 6 to 10, in the manufacturing apparatus 100 for a composite elastic member of this embodiment, the elastic member guiding device 110 includes a plate-shaped guide plate 112 as a guide member that guides the elastic members 10 into the plurality of grooves 214 on the outer peripheral surface of the anvil roll 210. The guide plate 112 has a tip 114a that is closest to the outer peripheral surface of the anvil roll 210, and a plurality of guide grooves 114b that are provided at the tip 114a and hold the plurality of elastic members 10 while being spaced apart from each other in a direction parallel to the axis of the anvil roll 210, so as to guide the plurality of elastic members 10 into the plurality of grooves 214 on the outer peripheral surface of the anvil roll 210 while being spaced apart from each other in a direction parallel to the axis of the anvil roll 210. The guide plate 112 is positioned so that the length L1 (free distance L1) of the elastic members 10 positioned between the guide grooves 114b and the grooves 214 of the anvil roll 210 is 30 mm or less.

[0097] In this way, by positioning the guide plate 112 so that the length L1 of the elastic member 10 positioned between the guide groove 114b and the groove 214 of the anvil roll 210 is 30 mm or less, it is possible to reduce the problem of the elastic member 10 coming off the groove 214 of the anvil roll 210 when the elastic member 10 is sent from the guide groove 114b to the groove 214 of the anvil roll 210, and as a result, it is possible to improve the cut prevention function of the elastic member 10.

[0098] (2) The guide plate 112 is preferably arranged so that the length L1 of the elastic member 10 located between the guide groove 114b and the groove 214 of the anvil roll 210 is 15 mm or less. In this case, it is possible to further reduce the problem of the elastic member 10 coming out of the groove 214 of the anvil roll 210 when the elastic member 10 is fed from the guide groove 114b to the groove 214 of the anvil roll 210, and as a result, it is possible to further improve the breakage prevention function of the elastic member 10.

[0099] (3) In the manufacturing apparatus 100 for a composite elastic member of this embodiment, the guide plate 112 is arranged so that the gap δ1 between the bottom P1 of the guide groove 114b and the outer peripheral surface of the convex portion 212 of the anvil roll 210 is 1 mm or less (preferably 0.3 mm or less). With this configuration, the guide groove 114b can be brought closer to the outer peripheral surface of the convex portion of the anvil roll 210, and it is possible to shorten the distance L1 from when the elastic member 10 leaves the guide groove 114b to when it is inserted into the groove 214 of the anvil roll 210. This makes it possible to further reduce the problem of the elastic member 10 coming out of the groove 214 of the anvil roll 210, and as a result, it is possible to further improve the breakage prevention function of the elastic member 10.

[0100] (4) In the composite elastic member manufacturing apparatus 100 of this embodiment, the guide member that guides the multiple elastic members 10 onto the outer circumferential surface of the anvil roll 210 while keeping them spaced apart in a direction parallel to the axis of the anvil roll 210 is composed of a plate-shaped guide plate 112. The leading edge 114a of the guide plate 112 is the edge of the guide plate 112 that is closest to the outer circumferential surface of the anvil roll 210 and has a tapered shape. Multiple guide grooves 114b are formed in the tapered leading edge 114a. In this configuration, by using the plate-shaped guide plate 112 with the tapered leading edge 114a, it is possible to position the guide plate 112 close to the outer circumferential surface of the anvil roll 210 without interfering with the anvil roll 210 or the sheets 2a, 2b wound around the outer circumferential surface of the anvil roll 210. This shortens the distance L1 between the guide groove 114b and the groove 214 of the anvil roll 210, further reducing the problem of the elastic member 10 coming off the groove 214 of the anvil roll 210. In addition, because the guide groove 114b is formed at the tapered tip 114a, it is also possible to reduce the frictional resistance between the guide plate 112 and the elastic member 10 when it passes through the guide groove 114b. As a result, it is possible to further improve the function of preventing the elastic member 10 from breaking.

[0101] (5) In the manufacturing apparatus 100 for a composite elastic member of this embodiment, the tip 114a of the guide plate 112 is positioned upstream (to the right in FIG. 10) of a contact point P2 on the outer circumferential surface of the anvil roll 210 where the anvil roll 210 comes into contact with the elastic member 10 in the rotation direction (counterclockwise in FIG. 10), and faces the upstream side. The guide plate 112 is positioned so that the bottom surface 114d facing the anvil roll 210 forms an angle θ1 of 30 degrees or less with the tangent to the anvil roll 210 at the contact point P2 where the anvil roll 210 and the elastic member 10 come into contact.

[0102] With this configuration, the bottom of the guide groove 114b can be brought closer to the outer peripheral surface of the anvil roll 210, and it is possible to shorten the distance L1 from when the elastic member 10 leaves the guide groove 114b to when it is inserted into the groove 214 of the anvil roll 210. This makes it possible to further reduce the problem of the elastic member 10 coming out of the groove 214 of the anvil roll 210, and as a result, it is possible to further improve the breakage prevention function of the elastic member 10.

[0103] (6) The manufacturing apparatus 100 for composite elastic members of this embodiment is further provided with a nip roll 104 which is arranged upstream of the horn 220 in the conveying direction of the sheets 2a, 2b (the rotation direction of the anvil roll 210) and cooperates with the anvil roll 210 to sandwich the two sheets and the elastic member 10 in the region where the elastic member 10 is inserted into the groove 214 of the anvil roll 210 (i.e., the section from the contact point P2 (see Figure 10(b)), which is the first position on the outer surface of the anvil roll 210 where the elastic member 10 is inserted into the groove 214, to the output section 221 of the horn 220 (see Figure 10(a))).

[0104] This configuration can further reduce the problem of the elastic member 10 inserted in the groove 214 of the anvil roll 210 coming out of the groove 214 of the anvil roll 210 before reaching the horn 220, thereby further improving the breakage prevention function of the elastic member 10. Moreover, even if the elastic member 10 contracts and attempts to return to its original position when it breaks downstream of the nip roll 104, the end of the elastic member 10 is sandwiched between the nip roll 104 and the anvil roll 210, preventing the elastic member 10 from returning, and facilitating the recovery operation of the manufacturing apparatus 100.

[0105] (7) In the manufacturing apparatus 100 for a composite elastic member of this embodiment, the elastic member guiding device 110 is further provided with a guide roll 111 that is disposed upstream of the guide plate 112 in the conveying direction of the elastic member 10 and guides the elastic member 10 into the guide groove 114b. With this configuration, it is possible to reliably guide the elastic member 10 into the guide groove 114b, and it is possible to prevent the elastic member 10 from coming out of the guide groove 114b.

[0106] (8) In the composite elastic member manufacturing apparatus 100 of this embodiment, the guide roll 111 (specifically, the guide roll 111A located most downstream among the multiple guide rolls 111) is arranged so that the distance L2 from when the elastic member 10 leaves the guide roll 111 to when it is inserted into the guide groove 114b is 50 mm or more. With this configuration, it is possible to eliminate the effects on the elastic member 10 of uneven rotation and rattle of the guide roll 111, such as sagging of the elastic member 10.

[0107] (9) In the manufacturing apparatus 100 for a composite elastic member of this embodiment, the conveying distance L3 from when the elastic member 10 comes into contact with the groove 214 of the anvil roll 210 until it is compressed by the horn 220 is 150 mm or less. With this configuration, the vibration suppression effect of the elastic member 10 is fully exerted as shown in Table 2 above, so it is possible to reduce the problem of the elastic member 10 coming out of the groove 214 of the anvil roll 210 between when the elastic member 10 comes into contact with the groove 214 of the anvil roll 210 and when it is compressed by the horn 220, and as a result, it is possible to further improve the breakage prevention function of the elastic member 10.

[0108] (Variation) (A) In this embodiment, a plate-shaped guide plate 112 has been described as an example of a guide member that guides multiple elastic members 10 to the outer peripheral surface of the anvil roll 210 while keeping them spaced apart in a direction parallel to the axis of the anvil roll 210, but the present invention is not limited to this.

[0109] As a modified example of the present invention, instead of the plate-shaped guide plate 112, a guide roller having multiple guide grooves on its outer circumferential surface may be used as another guide member, and the guide roller can also guide the multiple elastic members 10 into the multiple grooves 214 on the outer circumferential surface of the anvil roll 210 while keeping them spaced apart in a direction parallel to the axis of the anvil roll 210. In this case, by arranging the guide roller so that the distance L1 from when the elastic members 10 leave the guide grooves 114b to when they are inserted into the grooves 214 of the anvil roll 210 is 30 mm or less, it is possible to reduce the problem of the elastic members 10 coming out of the grooves 214 of the anvil roll 210 when the elastic members 10 are fed from the guide grooves to the grooves 214 of the anvil roll 210, and as a result, it is possible to improve the breakage prevention function of the elastic members 10.

[0110] (B) In the above embodiment, the joining device is an ultrasonic welding device that applies ultrasonic vibrations to the sheets 2a, 2b to generate frictional heat, thereby heating the sheets 2a, 2b. However, the specific configuration for heating and welding the sheets 2a, 2b is not limited to this. As another variation of the present invention, for example, a joining device that heats and welds the sheets 2a, 2b without vibrating them may be used, and in the joining step, the sheets 2a, 2b may be heated and welded without vibrating them, as in so-called heat sealing.

[0111] (C) In the above embodiment, the guide plate 112 is fixed so as not to move by screws or the like to a fixing member 113 fixed to a mirror plate or the like inside the device, as shown in Figures 10(a) and (b), but the present invention is not limited to this.

[0112] As yet another variation of the present invention, the guide plate 112 may be configured to be movable between a position close to the anvil roll 210 (conveying roller) shown in Figure 17 and a position spaced apart from the anvil roll 210 shown in Figure 18.

[0113] 17 and 18 includes, in addition to the plurality of guide rolls 111 and guide plate 112, a holding member 115 that holds both the guide rolls 111 and the guide plate 112, a support shaft 116 that supports the holding member 115 so that it can swing freely in the vertical direction, and a supply roll 117 that is arranged upstream of the guide roll 111 in the conveying direction of the elastic member 10. The rotation axes of the support shaft 116 and the supply roll 117 are fixed to predetermined positions inside the manufacturing apparatus 100 so as not to move. A groove for guiding the elastic member 10 is formed on the outer circumferential surface of each of the plurality of guide rolls 111 and the supply roll 117.

[0114] As shown in Figures 17 and 18, the holding member 115 that holds the guide roll 111 and the guide plate 112 swings up and down around the support shaft 116 as the center of rotation, allowing the guide plate 112 to move between a position close to the anvil roll 210 (conveying roller) shown in Figure 17 and a position spaced apart from the anvil roll 210 shown in Figure 18.

[0115] As shown in Figure 17, when the guide plate 112 is in a position close to the anvil roll 210 (i.e., the position when the manufacturing apparatus 100 is operating), the elastic member 10 is pressed from above by the guide plate 112, and moves in the order of the supply roll 117, multiple guide rolls 111, and guide plate 112, and is sent to the outer peripheral surface of the anvil roll 210.

[0116] 18, when the guide plate 112 is in a position spaced apart from the anvil roll 210 (a position for threading the elastic member 10 (such as rubber thread)), the guide plate 112 is retracted above the elastic member 10, making it easy to set the elastic member 10 in the guiding device 110 (specifically, to loop the elastic member 10 over the groove of the most downstream guide roll 111A of the multiple guide rolls 111 and the outer periphery of the anvil roll 210). After the elastic member 10 has been set in the guiding device 110, when the guide plate 112 shown in FIG. 17 is returned to a position close to the anvil roll 210, the elastic member 10 is inserted into the groove 114b (see FIG. 10(b)) of the guide plate 112 and simultaneously looped over the grooves of the multiple guide rolls 111, allowing the guiding device 110 to return to the state shown in FIG. 17.

[0117] <Summary of the embodiment> The above embodiment can be summarized as follows. The composite elastic member manufacturing apparatus according to the embodiment is an apparatus for manufacturing a composite elastic member having two sheets and a plurality of elastic members sandwiched between the two sheets by transporting two sheets along their longitudinal direction and bonding the two sheets together and the sheets together with a plurality of elastic members, and is equipped with a joining device that welds and bonds each elastic member to the sheet and the two sheets together while sandwiching each elastic member between the two sheets being transported, and a guide device that guides the two sheets and each elastic member to the joining device so that each elastic member extends in the longitudinal direction and is sandwiched between the two sheets, and the joining device includes a conveying roller that has an outer peripheral surface that conveys the two sheets with the sandwiched elastic members in the longitudinal direction of the sheets and rotates around a predetermined axis, and a roller that faces the outer peripheral surface of the conveying roller and welds the outer peripheral member to the conveying roller. and a clamping device that clamps the two sheets with the elastic members sandwiched between the conveying rollers and the clamping device, and is configured to apply heat to the sheets between the conveying rollers and the clamping device, wherein the outer peripheral surface of the conveying roller is formed with at least one convex portion that protrudes radially outward from the outer peripheral surface, and the convex portion has a plurality of grooves that extend in the conveying direction of the conveying roller and are spaced apart in a direction parallel to the axis, and the guide device includes a guide member having a tip that is closest to the outer peripheral surface of the conveying roller and a plurality of guide grooves that are provided at the tip and hold the plurality of elastic members in a state where they are spaced apart in a direction parallel to the axis of the conveying roller so as to guide the plurality of elastic members into the plurality of grooves of the conveying roller, respectively, and the guide member is arranged so that the length of the elastic members located between the guide groove and the groove of the conveying roller is 30 mm or less.

[0118] As a result of extensive research into a technology for using a guide member to reliably guide an elastic member into a groove on the outer surface of a conveying roller without it falling off, the inventors discovered that if the distance that the elastic member moves in the air between the guide groove of the guide member and the groove of the conveying roller, i.e., the free distance of the elastic member, is reduced to a predetermined distance or less, the elastic member can be reliably guided into the groove of the conveying roller and prevented from falling off from the groove, and they created the above-mentioned manufacturing device.

[0119] In other words, in the configuration of the above manufacturing apparatus, by arranging the guide member so that the length of the elastic member located between the guide groove and the groove of the conveying roller is 30 mm or less, it is possible to reduce the problem of the elastic member coming off the groove of the conveying roller when the elastic member is sent from the guide groove to the groove of the conveying roller, and as a result, it is possible to improve the function of preventing the elastic member from breaking.

[0120] In the above-mentioned manufacturing apparatus for composite elastic members, the guide member is preferably arranged so that the length of the elastic member located between the guide groove and the groove of the conveying roller is 15 mm or less.

[0121] In this configuration, by positioning the guide member so that the length of the elastic member located between the guide groove and the groove of the conveying roller is 15 mm or less, it is possible to further reduce the problem of the elastic member coming off the groove of the conveying roller when the elastic member is sent from the guide groove to the groove of the conveying roller, and as a result, it is possible to further improve the breakage prevention function of the elastic member.

[0122] In the above-described manufacturing apparatus for composite elastic members, the guide members are preferably arranged so that the shortest distance between the bottom of the guide groove and the outer peripheral surface of the convex portion of the conveying roller is 1 mm or less.

[0123] With this configuration, the guide groove can be brought closer to the outer peripheral surface of the convex portion of the conveying roller, and the distance that the elastic member must travel before leaving the guide groove and being inserted into the groove of the conveying roller can be shortened, which further reduces the risk of the elastic member coming out of the groove of the conveying roller, and as a result, the ability to prevent the elastic member from breaking can be further improved.

[0124] In the above-mentioned manufacturing apparatus for composite elastic members, the guide member is formed in a plate shape, and the tip is the edge of the plate-shaped guide member that is closest to the outer peripheral surface of the conveying roller, and also has a tapered shape, and it is preferable that the multiple guide grooves are formed at the tapered tip.

[0125] In this configuration, by using a plate-shaped guide member with a tapered tip, the guide member can be positioned close to the outer circumferential surface of the conveying roller without interfering with the conveying roller or the sheet wound around the outer circumferential surface of the conveying roller. This shortens the distance between the guide groove and the groove of the conveying roller, further reducing the risk of the elastic member coming off the groove of the conveying roller. Furthermore, because the guide groove is formed at a tapered tip, it is also possible to reduce frictional resistance between the guide member and the elastic member when it passes through the guide groove. As a result, the ability to prevent the elastic member from breaking can be further improved.

[0126] In the above-mentioned manufacturing apparatus for composite elastic members, it is preferable that the tip of the guide member is positioned upstream in the rotation direction of the conveying roller from the contact point on the outer surface of the conveying roller where it comes into contact with the elastic member, and faces the upstream side, and that the guide plate is positioned so that the surface facing the conveying roller forms an angle of 30 degrees or less with the tangent to the conveying roller at the contact point.

[0127] With this configuration, the bottom of the guide groove can be brought closer to the outer circumferential surface of the conveying roller, shortening the distance the elastic member needs to leave the guide groove and enter the groove of the conveying roller, further reducing the risk of the elastic member coming out of the groove of the conveying roller and, as a result, further improving the ability to prevent the elastic member from breaking.

[0128] In the above-mentioned manufacturing apparatus for composite elastic members, it is preferable that the apparatus further includes a nip roll that is arranged upstream of the clamping device in the conveying direction of the sheet and cooperates with the conveying roller to clamp the two sheets and the elastic member in the area where the elastic member is inserted into the groove of the conveying roller.

[0129] With this configuration, it is possible to further reduce the problem of the elastic member inserted in the groove of the conveying roller coming out of the groove of the conveying roller before reaching the clamping device, and as a result, it is possible to further improve the function of preventing the elastic member from breaking. Moreover, even if the elastic member tries to return to its original position by contracting if it breaks downstream of the nip roll, the end of the elastic member is sandwiched between the nip roll and the conveying roller, so the elastic member is prevented from returning, facilitating the recovery work of the manufacturing equipment.

[0130] The above-described manufacturing apparatus for a composite elastic member preferably further comprises a guide roll that is arranged upstream of the guide member in the conveying direction of the elastic member and that guides the elastic member into the guide groove.

[0131] With this configuration, it is possible to reliably guide the elastic member into the guide groove, and it is possible to prevent the elastic member from coming off the guide groove.

[0132] In the above-mentioned manufacturing apparatus for composite elastic members, the guide rolls are preferably arranged so that the distance from when the elastic member leaves the guide rolls to when it is inserted into the guide groove is 50 mm or more.

[0133] With this configuration, it is possible to eliminate the influence on the elastic member caused by uneven rotation and rattle of the guide roll, such as slack in the elastic member.

[0134] In the above-described manufacturing apparatus for a composite elastic member, it is preferable that the conveying distance from when the elastic member contacts the groove of the conveying roller until when the elastic member is clamped by the clamping device is 150 mm or less.

[0135] With this configuration, it is possible to reduce the problem of the elastic member coming off the groove of the conveying roller between the time the elastic member comes into contact with the groove of the conveying roller and the time it is compressed by the compression device, thereby further improving the ability of the elastic member to prevent cutting.

[0136] In the above-described manufacturing apparatus for a composite elastic member, it is preferable that the guide member is movable between a position close to the transport roller and a position spaced apart from the transport roller.

[0137] In this configuration, the guide member can be moved to a position spaced apart from the transport roller, thereby facilitating the operation of setting the elastic member in the guide device.

[0138] As described above, the manufacturing apparatus for a composite elastic member according to this embodiment can reduce the problem of the elastic member coming out of the grooves of the conveying rollers, thereby improving the breakage prevention function.

Claims

1. A manufacturing apparatus for manufacturing a composite elastic member having two sheets and a plurality of elastic members sandwiched between the two sheets, by bonding the sheets together and bonding the sheets together and a plurality of elastic members while conveying the two sheets along their longitudinal directions, comprising: a joining device that welds and joins each of the elastic members to the sheet and the two sheets together while sandwiching each of the elastic members between the two sheets being conveyed; a guide device that guides the two sheets and each of the elastic members to the joining device so that each of the elastic members extends in its longitudinal direction and is sandwiched between the two sheets; The joining device is configured to include a conveying roller having an outer peripheral surface that conveys the two sheets with the elastic members sandwiched therebetween in the longitudinal direction of the sheets and rotates around a predetermined axis, and a clamping device that faces the outer peripheral surface of the conveying roller and clamps the two sheets with the elastic members sandwiched therebetween between the outer peripheral surface and the conveying roller, and to apply heat to the sheets between the conveying roller and the clamping device, At least one protrusion protruding radially outward from the outer circumferential surface of the conveying roller is formed on the outer circumferential surface of the conveying roller, the protrusion has a plurality of grooves extending in a conveying direction of the conveying roller and spaced apart in a direction parallel to the axis, the guide device includes a guide member having a tip closest to the outer peripheral surface of the conveying roller and a plurality of guide grooves provided at the tip and holding the plurality of elastic members in a state spaced apart from each other in a direction parallel to the axis of the conveying roller so as to guide the plurality of elastic members into the plurality of grooves of the conveying roller, respectively; the guide member is fixed at a predetermined position facing the outer circumferential surface of the conveying roller so that the length of the elastic member located between the guide groove and the groove of the conveying roller is in a range of 1 to 30 mm and the guide member is in a stationary state during operation of the manufacturing apparatus; the tip of the guide member is disposed upstream in the rotation direction of the conveying roller from a contact point on the outer circumferential surface of the conveying roller where the tip of the guide member contacts the elastic member, the elastic member engaged with the guide groove is bent at the bottom of the guide groove, extends in a tangential direction of the contact point with the outer circumferential surface of the conveying roller, and is inserted into the groove on the outer circumferential surface of the conveying roller at the contact point. A manufacturing apparatus for a composite elastic member.

2. 2. The manufacturing apparatus for a composite elastic member according to claim 1, The guide member is arranged so that the length of the elastic member located between the guide groove and the groove of the conveying roller is 15 mm or less. A manufacturing apparatus for a composite elastic member.

3. 3. The manufacturing apparatus for the composite elastic member according to claim 1 or 2, the guide member is disposed so that the shortest distance between the bottom of the guide groove and the outer circumferential surface of the convex portion of the conveying roller is 1 mm or less. A manufacturing apparatus for a composite elastic member.

4. The manufacturing apparatus for the composite elastic member according to any one of claims 1 to 3, The guide member is formed in a plate shape, the leading end is an edge of the plate-shaped guide member that is closest to the outer circumferential surface of the conveying roller, and has a tapered shape; The plurality of guide grooves are formed at the tapered tip. A manufacturing apparatus for a composite elastic member.

5. 5. The manufacturing apparatus for a composite elastic member according to claim 4, the tip of the guide member faces upstream in the rotation direction of the conveying roller, the guide member is disposed so that a surface facing the conveying roller forms an angle of 30 degrees or less with respect to a tangent to the conveying roller at the contact point; A manufacturing apparatus for a composite elastic member.

6. The manufacturing apparatus for the composite elastic member according to any one of claims 1 to 5, one of the two sheets is introduced into a portion of the outer circumferential surface of the conveying roller that is near the nipping device and is upstream of the nipping device in the conveying direction of the conveying roller; the other of the two sheets is introduced into a position on the outer circumferential surface of the conveying roller that is farther upstream from the clamping device than the introduction position of the one sheet, the elastic member is introduced onto the outer peripheral surface of the conveying roller at a position between a position where one of the two sheets is introduced onto the conveying roller and a position where the other of the two sheets is introduced onto the conveying roller; the elastic member is introduced at a position closer to a position where one of the two sheets is introduced than a position where the other of the two sheets is introduced; a nip roll disposed between the nip device and an introduction position of the elastic member in the sheet conveying direction, the nip roll guiding one of the two sheets to the conveying roller and cooperating with the conveying roller to nip the two sheets and the elastic member in a region where the elastic member is inserted into the groove of the conveying roller; A manufacturing apparatus for a composite elastic member.

7. The manufacturing apparatus for the composite elastic member according to any one of claims 1 to 6, The elastic member may further include a guide roll disposed upstream of the guide member in the conveying direction of the elastic member, the guide roll guiding the elastic member into the guide groove. A manufacturing apparatus for a composite elastic member.

8. 8. The manufacturing apparatus for a composite elastic member according to claim 7, The guide roll is arranged so that the distance from the guide roll until the elastic member is inserted into the guide groove is 50 mm or more. A manufacturing apparatus for a composite elastic member.

9. The manufacturing apparatus for the composite elastic member according to any one of claims 1 to 8, a conveying distance from when the elastic member contacts the groove of the conveying roller to when the sheet is clamped by the clamping device is 150 mm or less; A manufacturing apparatus for a composite elastic member.

10. A manufacturing apparatus for manufacturing a composite elastic member having two sheets and a plurality of elastic members sandwiched between the two sheets by joining the two sheets together and the sheets together with a plurality of elastic members while conveying the two sheets along their longitudinal direction, comprising: a joining device that welds and joins each of the elastic members to the sheet and the two sheets together while sandwiching each of the elastic members between the two sheets being conveyed; a guide device that guides the two sheets and each of the elastic members to the joining device so that each of the elastic members extends in its longitudinal direction and is sandwiched between the two sheets; The joining device is configured to include a conveying roller having an outer peripheral surface that conveys the two sheets with the elastic members sandwiched therebetween in the longitudinal direction of the sheets and rotates around a predetermined axis, and a clamping device that faces the outer peripheral surface of the conveying roller and clamps the two sheets with the elastic members sandwiched therebetween between the outer peripheral surface and the conveying roller, and to apply heat to the sheets between the conveying roller and the clamping device, At least one protrusion protruding radially outward from the outer circumferential surface of the conveying roller is formed on the outer circumferential surface of the conveying roller, the protrusion has a plurality of grooves extending in a conveying direction of the conveying roller and spaced apart in a direction parallel to the axis, the guide device includes a guide member having a tip closest to the outer peripheral surface of the conveying roller and a plurality of guide grooves provided at the tip and holding the plurality of elastic members in a state spaced apart from each other in a direction parallel to the axis of the conveying roller so as to guide the plurality of elastic members into the plurality of grooves of the conveying roller, respectively; the guide member is disposed at a predetermined position facing the outer circumferential surface of the conveying roller so that the length of the elastic member located between the guide groove and the groove of the conveying roller is in a range of 1 to 30 mm during operation of the manufacturing apparatus; the tip of the guide member is disposed upstream in a rotation direction of the conveying roller from a contact point between the outer circumferential surface of the conveying roller and the elastic member during operation of the manufacturing apparatus; the elastic member engaged with the guide groove is bent at the bottom of the guide groove during operation of the manufacturing apparatus, extends in a tangential direction of the contact point with the outer circumferential surface of the conveying roller, and is inserted into the groove of the outer circumferential surface of the conveying roller at the contact point; the guiding device includes a holding member that movably holds the guide member so that the guide member is disposed at the predetermined position close to the conveying roller when the manufacturing apparatus is in operation, and the guide member is disposed at a position spaced apart from the conveying roller when the elastic member is set in the guiding device; The guide member is fixed to the holding member so as to be stationary during operation of the manufacturing apparatus. A manufacturing apparatus for a composite elastic member.

11. 2. The manufacturing apparatus for a composite elastic member according to claim 1, one of the two sheets is introduced into a portion of the outer circumferential surface of the conveying roller that is near the nipping device and is upstream of the nipping device in the conveying direction of the conveying roller; the other of the two sheets is introduced into a position on the outer circumferential surface of the conveying roller that is farther upstream from the clamping device than the introduction position of the one sheet, the elastic member is introduced onto the outer peripheral surface of the conveying roller at a position between a position where one of the two sheets is introduced onto the conveying roller and a position where the other of the two sheets is introduced onto the conveying roller; the elastic member is introduced at a position closer to a position where one of the two sheets is introduced than a position where the other of the two sheets is introduced; A manufacturing apparatus for a composite elastic member.

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