Laminate manufacturing apparatus

Abstract

Provided is a laminate manufacturing apparatus with which it is possible to even more efficiently manufacture a continuous laminate for manufacturing a wearable article.　A pair of first continuous sheets (2a, 2b) supplied to a first anvil roll (16) are cut by a cutting device (14), pairs of sheet pieces (3a, 3b) are sequentially formed, and the sheet pieces (3a, 3b) are transported at a higher speed than the first continuous sheets (2a, 2b). A second anvil roll (20) having an outer circumferential surface (20s) on which suction holes (30a, 30b) are formed receives, suctions, and transports the sheet pieces (3a, 3b). A second continuous sheet (4) is supplied between the sheet pieces (3a, 3b), a first continuous elastic member (5) is superposed on the sheet pieces (3a, 3b), a second continuous elastic member (6) is superposed on the second continuous sheet (4), a third continuous sheet (8) is superposed on the first continuous elastic member (5) and the second continuous elastic member (6), and joining is performed by using a joining device (28) to form a continuous laminate (9). The continuous laminate (9) is divided into a pair of continuous laminates to be used in manufacturing a wearable article.

Description

Laminate manufacturing equipment

[0001] The present invention relates to a laminate manufacturing apparatus, and more particularly to an apparatus for manufacturing a continuous laminate used in the manufacture of absorbent articles.

[0002] BACKGROUND ART Absorbent articles such as disposable diapers and disposable pants are manufactured by joining an absorbent body to a continuous laminate in which a sheet such as a nonwoven fabric and an elastic member such as rubber thread are laminated.

[0003] For example, Fig. 9(a) is a schematic perspective view showing a manufacturing method of a worn article. As shown in Fig. 9, a plurality of continuous elastic members F3 are arranged in a stretched state on a continuous sheet W1, and a plurality of discontinuous sheets W2 are arranged thereon at predetermined intervals P. An adhesive C is applied to the continuous sheet W1 in advance to form joints 32B at both end portions 32A of the discontinuous sheets W2 in the conveying direction X and at a central portion 32C between the end portions 32A and spaced from the end portions 32A, where the continuous sheet W1 and the discontinuous sheets W2 are joined to each other.

[0004] Next, the continuous elastic member F3 is cut between adjacent discontinuous sheets W2, W2. Next, in the overlapping region α of the continuous sheet W1 and the discontinuous sheet W2, a plurality of welded portions 42 are formed to join the continuous sheet W1 and the discontinuous sheet W2 to each other. In the continuous laminate L formed by joining the two sheets W1, W2 to each other, heat marks 43 are formed in the same dot pattern as the welded portions 42 in the non-overlapping region β where the continuous sheet W1 and the discontinuous sheet W2 do not overlap. This heating and welding is performed on a second anvil roll 61 (see FIG. 10 ). The continuous elastic member F3 is appropriately cut in the non-overlapping region β of the continuous laminate L to prevent elastic contraction in the non-overlapping region β.

[0005] As shown in Fig. 9(b) , a plurality of absorbent bodies 23 are sequentially arranged at intervals between discontinuous sheets W2 in the non-overlapping region β of a pair of continuous laminates L, L spaced apart in the width direction Y, so as to straddle the gap between the discontinuous sheets W2, and both ends of the absorbent bodies 23 are joined to the non-overlapping region β of the pair of continuous laminates L, L. The absorbent bodies 23 are then cut at the intended cutting positions indicated by the two-dot chain lines to form individual pieces of the wearing article 1. The individual pieces of the wearing article 1 are folded in two to form the diaper-type or pants-type wearing article 1. By arranging the discontinuous sheets W2, W2 at an interval and providing the non-overlapping region β, the amount of material used can be reduced.

[0006] Fig. 10(a) is a schematic diagram of a laminate manufacturing apparatus for manufacturing a continuous laminate L. Fig. 10(b) is a front view of a second anvil roll 161. As shown in Fig. 10(a), a discontinuous sheet W2, a continuous elastic member F3, and a continuous sheet W1 coated with adhesive by a coating device 164 are supplied to the outer peripheral surface of the second anvil roll 161, and are welded together using an ultrasonic horn 160.

[0007] The discontinuous sheet W2 is formed sequentially by conveying a continuous sheet W, separate from the continuous sheet W1, on a belt conveyor 170 and passing it between a cutter roll 171 and a first anvil roll 172. A variable speed drum 173 receives the discontinuous sheet W2 from the first anvil roll 172, conveys the discontinuous sheet W2 at intervals in the conveyance direction, and delivers it to a second anvil roll 161. As shown in FIG. 10(b) , a large number of protrusions 162 are formed on the second anvil roll 161, and welded portions 42 and heated marks 43 are formed corresponding to the protrusions 162 (see, for example, Patent Document 1).

[0008] International Publication No. 2021 / 140831

[0009] Although this laminate manufacturing apparatus can efficiently manufacture continuous laminates, it is desired to improve it so that it can be manufactured even more efficiently.

[0010] In view of the above circumstances, an object of the present invention is to provide a laminate manufacturing apparatus that can more efficiently manufacture a continuous laminate for manufacturing a wearing article.

[0011] In order to solve the above problems, the present invention provides a laminate manufacturing apparatus configured as follows.

[0012] The laminate manufacturing apparatus includes: (a) a cutting device having a cutting blade; (b) a first anvil roll having an outer peripheral surface that sucks and conveys a pair of first continuous sheets with a predetermined gap between the pair of first continuous sheets, the first anvil roll being disposed so that the cutting blade of the cutting device approaches or abuts against the outer peripheral surface to cut the pair of first continuous sheets and sequentially form a pair of sheet pieces, the outer peripheral surface sucking the pair of sheet pieces and conveying them at a higher speed than the pair of first continuous sheets; and (c) a first anvil roll having an outer peripheral surface formed with a plurality of suction holes and a plurality of protrusions, the outer peripheral surface being disposed so that the first anvil roll is positioned to cut the pair of first continuous sheets into a pair of sheet pieces. (d) a joining device that is arranged to face the outer circumferential surface of the second anvil roll and cooperates with the protrusions of the second anvil roll to form a joint; and (e) a joining device that is arranged to face the outer circumferential surface of the first anvil roll upstream of the cutting device in the rotation direction of the first anvil roll and downstream of the second anvil roll in the rotation direction of the first anvil roll, and that is arranged to receive the pair of sheet pieces from the first anvil roll, and whose outer circumferential surface sucks and conveys the pair of sheet pieces by suction from the suction holes. (f) a second continuous sheet supply unit that supplies the second continuous sheet to the outer peripheral surface of the second anvil roll downstream of the first anvil roll in the rotation direction of the second anvil roll and upstream of the joining device in the rotation direction of the second anvil roll so that the second continuous sheet is disposed between the pair of sheet pieces; and (g) a second continuous sheet supply unit that supplies the second continuous sheet to the outer peripheral surface of the second anvil roll downstream of the second continuous sheet supply unit in the rotation direction of the second anvil roll and upstream of the joining device in the rotation direction of the second anvil roll so that the second continuous sheet is disposed between the pair of sheet pieces. The apparatus includes: (i) a continuous elastic member supply unit that supplies a first continuous elastic member toward the outer peripheral surface of the second anvil roll so that it overlaps the pair of sheet pieces and a second continuous elastic member toward the outer peripheral surface of the second anvil roll so that it overlaps the pair of sheet pieces; and (ii) a third continuous sheet supply unit that supplies a third continuous sheet toward the outer peripheral surface of the second anvil roll downstream of the continuous elastic member supply unit in the direction of rotation of the second anvil roll and upstream of the joining device in the direction of rotation of the second anvil roll so that it overlaps the first continuous elastic member and the second continuous elastic member.

[0013] According to the above configuration, a continuous laminate manufactured using the laminate manufacturing apparatus can be divided at the midpoint in the width direction to form a pair of continuous laminates to be used in manufacturing absorbent articles. Therefore, when continuously manufacturing absorbent articles, only one laminate manufacturing apparatus is required. In contrast, conventional laminate manufacturing apparatuses require two apparatuses to separately manufacture a pair of continuous laminates in order to continuously manufacture absorbent articles.

[0014] Therefore, the laminate manufacturing apparatus can efficiently manufacture a continuous laminate for manufacturing a wearing article.

[0015] Preferably, the suction holes are formed in the sheet piece area on the outer peripheral surface of the second anvil roll where the pair of sheet pieces are arranged, and in an adjacent area outside the sheet piece area and adjacent to the boundary line of the sheet piece area.

[0016] In this case, the suction from the suction holes formed in the adjacent region prevents the sheet piece being sucked into the sheet piece region on the outer circumferential surface of the second anvil roll and conveyed thereto from being turned up.

[0017] Preferably, a plurality of protrusions extending in a helical gear shape are formed on the outer peripheral surface of the second anvil roll as the protrusions, and when viewed from the direction of the central axis of rotation of the second anvil roll, adjacent protrusions are in contact with or close to each other, and the suction holes are formed between the adjacent protrusions.

[0018] In this case, the joint can be formed continuously or almost continuously along the helical gear-shaped protrusion, and the output of the joining device can be reduced compared to when the joint is formed intermittently along the spur gear-shaped protrusion.

[0019] Preferably, the protrusions of the second anvil roll are formed with a plurality of grooves that intersect with the protrusions, the continuous elastic member supply unit supplies each of the first continuous elastic member and the second continuous elastic member so that they follow one of the grooves, and the grooves and the suction holes are spaced apart from each other in the direction of the central axis of rotation of the second anvil roll.

[0020] In this case, the first continuous elastic member and the second continuous elastic member are supplied to the second anvil roll so as not to face the suction holes, and are therefore less susceptible to the influence of suction from the suction holes.

[0021] Preferably, the plurality of grooves have different configurations depending on the position in the circumferential direction of the second anvil roll.

[0022] In this case, the first continuous elastic member and the second continuous elastic member can be joined to the sheet piece or the second continuous sheet and the third continuous sheet with an appropriate strength depending on the position, or can be not joined depending on the position.

[0023] Preferably, the laminate manufacturing apparatus further includes (i) a moving device that moves the cutting device to a cutting position where the cutting blade of the cutting device approaches or abuts against the outer peripheral surface of the first anvil roll to cut the pair of first continuous sheets, and a retracted position where the cutting blade of the cutting device moves away from the outer peripheral surface of the first anvil roll and does not cut the pair of first continuous sheets.

[0024] In this case, the pair of first continuous sheets are supplied to the second anvil roll without being cut by the cutting device, and the first continuous sheet is placed in the area where the absorbent main body is to be placed, thereby forming a continuous laminate in which the first continuous elastic member is not exposed.When starting operation of the laminate manufacturing apparatus, by moving the cutting device to the cutting position at an appropriate time, it is possible to produce a continuous laminate while suppressing shrinkage of the pair of sheet pieces.Furthermore, when stopping operation of the laminate manufacturing apparatus, by moving the cutting device to the retracted position at an appropriate time, it is possible to stop operation in a state in which operation can be easily resumed.

[0025] According to the present invention, a continuous laminate for manufacturing a wearing article can be manufactured more efficiently.

[0026] FIG. 1 is a schematic diagram showing the manufacturing process of a continuous laminate. (Example 1) FIG. 2 is a schematic diagram showing the manufacturing process of a continuous laminate. (Example 1) FIG. 3 is a schematic diagram of a laminate manufacturing apparatus. (Example 1) FIG. 4 is a development view of the outer circumferential surface of the second anvil roll. (Example 1) FIG. 5 is an enlarged view of a main part of FIG. 4. (Example 1) FIG. 6 is an enlarged view of a main part continuing from the bottom of FIG. 5. (Example 1) FIG. 7 is a partial enlarged view of FIG. 5. (Example 1) FIG. 8(a) is a schematic left side view of the second anvil roll, FIG. 8(b) is a schematic front view of the second anvil roll, and FIG. 8(c) is a schematic right side view of the second anvil roll. (Example 1) FIG. 9(a) and FIG. 9(b) are schematic diagrams showing the manufacturing process of a continuous laminate. (Conventional Example 1) FIG. 10(a) is a schematic diagram of a laminate manufacturing apparatus, and FIG. 10(b) is a front view of the second anvil roll. (Conventional Example 1)

[0027] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0028] First Embodiment A laminate manufacturing apparatus 10 according to a first embodiment will be described with reference to FIGS. 1 to 7. FIG.

[0029] First, an outline of the process for producing a continuous laminate 9 using a laminate production apparatus 10 will be described with reference to Figures 1 and 2. Figures 1 and 2 are schematic diagrams showing the process for producing a continuous laminate 9.

[0030] As shown in Figures 1 and 2, a first continuous nonwoven fabric 50, a second continuous nonwoven fabric 52, a plurality of first continuous elastic members 5, and a plurality of second continuous elastic members 6 are prepared, and then each is transported and stacked to form a continuous laminate 9.

[0031] Specifically, as indicated by reference symbol S1, a slit 51 is formed in the widthwise middle of the first continuous nonwoven fabric 50, dividing the first continuous nonwoven fabric 50 into a pair of first continuous sheets 2a, 2b, which are then transported with a predetermined gap between them. Also, as indicated by reference symbol S2, a slit 53 is formed in the widthwise middle of the second continuous nonwoven fabric 52, dividing the second continuous nonwoven fabric 52 into a second continuous sheet 4 and a third continuous sheet 8, which are then transported.

[0032] Next, as shown by reference symbol S3, the pair of first continuous sheets 2a, 2b are cut to sequentially form a pair of sheet pieces 3a, 3b, and the sheet pieces 3a, 3b are conveyed with a gap therebetween in the conveying direction. Next, as shown by reference symbol S4, the second continuous sheet 4 is placed between one sheet piece 3a and the other sheet piece 3b.

[0033] Next, as shown by reference symbol S5, the first continuous elastic member 5 is laid on the pair of sheet pieces 3a, 3b, the second continuous elastic member 6 is laid on the second continuous sheet 4, and then the third continuous sheet 8 is laid on top of it, and they are joined at appropriate locations to form a continuous laminate 9. The third continuous sheet 8 is laid on top of it so that the first continuous elastic member 5 is sandwiched between the pair of sheet pieces 3a, 3b and the third continuous sheet 8, and the second continuous member 6 is sandwiched between the second continuous sheet 4 and the third continuous sheet 8.

[0034] The laminate manufacturing apparatus 10 is used in the steps indicated by the reference numerals S3 to S5.

[0035] Next, the laminate manufacturing apparatus 10 will be described with reference to Fig. 3. Fig. 3(a) and Fig. 3(b) are schematic diagrams showing the configuration of the laminate manufacturing apparatus 10, Fig. 3(a) shows a state in which the cutting device 14 is disposed at a cutting position 14p, and Fig. 3(b) shows a state in which the cutting device 14 is disposed at a retracted position 14q.

[0036] As shown in Figures 3(a) and 3(b), the laminate manufacturing apparatus 10 is arranged so that the first anvil roll 16 and the second anvil roll 20, which rotate in opposite directions as indicated by arrows 16x and 20x, are adjacent to and face each other.

[0037] The first anvil roll 16 has an outer peripheral surface 16s, and conveys the pair of continuous sheets 2a, 2b and the pair of sheet pieces 3a, 3b formed by cutting the pair of continuous sheets 2a, 2b by the cutting device 14 by sucking them onto the outer peripheral surface 16s. Although not shown, the outer peripheral surface 16s has a plurality of suction holes formed in the area where the pair of continuous sheets 2a, 2b are arranged, and a suction source connected to a negative pressure source is arranged inside the first anvil roll 16, so that the suction holes communicate with the suction source.

[0038] The first anvil roll 16 increases its rotation speed when the pair of continuous sheets 2a, 2b is cut to form a pair of sheet pieces 3a, 3b, and returns to its original rotation speed when the pair of sheet pieces 3a, 3b is delivered to the second anvil roll 20. As a result, the pair of sheet pieces 3a, 3b that are formed one after another are transported at a higher speed than the pair of continuous sheets 2a, 2b, and are delivered to the second anvil roll 20 with an interval in the transport direction.

[0039] A cutting device 14 and a first continuous sheet supply section 12 are disposed around the first anvil roll 16 .

[0040] The cutting device 14 is, for example, a cutter roll 14 having a cutter 14a which is a cutting blade, and rotates in the opposite direction to the first anvil roll 16 as indicated by an arrow 14x.

[0041] The cutter roll 14 is supported so as to be movable in a direction toward and away from the first anvil roll 16, and moves to a cutting position 14p approaching and facing the first anvil roll 16 as shown in Fig. 3(a) and a retracted position 14q away from the first anvil roll 16 as shown in Fig. 3(b) by extension and contraction of a rod 15a of an air cylinder 15, which is a moving device 15. The moving device 15 selectively positions the cutter roll 14 at the cutting position 14p or the retracted position 14q.

[0042] 3( a), when the cutter roll 14 is positioned at the cutting position 14p, there is no or almost no gap between the cutting edge circle 14b of the cutter 14a and the outer peripheral surface 16s of the first anvil roll 16, and the cutter 14a approaches or abuts against the outer peripheral surface 16s of the first anvil roll 16. The cutter roll 14 positioned at the cutting position 14p rotates in synchronization with the first anvil roll 16, and the pair of first continuous sheets 2a, 2b being sucked and transported by the outer peripheral surface 16s of the first anvil roll 16 are cut to a predetermined length by the cutter 14a of the cutter roll 14, and a pair of sheet pieces 3a, 3b are sequentially formed.

[0043] On the other hand, as shown in Figure 3(b), when the cutter roll 14 is positioned at the retracted position 14q, a sufficient gap is created between the cutting edge circle 14b of the cutter 14a and the outer peripheral surface 16s of the first anvil roll 16, and the pair of first continuous sheets 2a, 2b are not cut.

[0044] It is also possible to fix the cutter roll 14 at the cutting position 14p without providing the moving device 15.

[0045] The first continuous sheet supply unit 12 supplies a pair of first continuous sheets 2a, 2b to the outer peripheral surface 16s of the first anvil roll 16, the outer peripheral surface 16s being located upstream of the cutter roll 14 in the rotation direction of the first anvil roll 16 and downstream of the second anvil roll 20 in the rotation direction of the first anvil roll 16, with a predetermined gap between the pair of first continuous sheets 2a, 2b. The first continuous sheet supply unit 12 is, for example, a belt conveyor 12, in which an air-permeable endless belt 12a circulates. A suction source (not shown) connected to a negative pressure source is disposed inside the endless belt 12a, and the pair of first continuous sheets 2a, 2b are sucked onto the endless belt 12a and transported. The first continuous sheet supply unit 12 may also be a rotatably supported guide roll, or the like.

[0046] The second anvil roll 20 has an outer peripheral surface 20s, and conveys the pair of sheet pieces 3a, 3b by sucking them onto the outer peripheral surface 20s. As will be described in detail later, a plurality of suction holes are formed in the outer peripheral surface 20s, and a suction source (not shown) connected to a negative pressure source is disposed inside the second anvil roll 20, and the suction holes are configured to communicate with the suction source.

[0047] Arranged around the second anvil roll 20 are a joining device 28 , a first continuous sheet supply section 22 , a continuous elastic member supply section 24 , and a third continuous sheet supply section 26 .

[0048] The joining device 28 is disposed to face the outer peripheral surface 20s of the second anvil roll 20, and cooperates with protrusions (described in detail below) of the second anvil roll 20 to form joints, thereby joining the continuous laminate 9. The joining device 28 is, for example, an ultrasonic horn 28 for ultrasonic bonding. The joining device 28 may also be a heat welding device or the like.

[0049] The second continuous sheet supply unit 22 supplies the second continuous sheet 4 along the outer peripheral surface 20s of the second anvil roll 20, to the outer peripheral surface 20s of the second anvil roll 20, which is located downstream of the first anvil roll 16 in the rotation direction of the second anvil roll 20 and upstream of the joining device 28 in the rotation direction of the second anvil roll 20. The second continuous sheet supply unit 22 is, for example, a rotatably supported guide roll 22. The second continuous sheet supply unit 22 may also be a belt conveyor like the first continuous sheet supply unit 12.

[0050] The continuous elastic member supply unit 24 supplies the first continuous elastic member 5 and the second elastic member 6 along the outer peripheral surface 20s of the second anvil roll 20 toward the outer peripheral surface 20s of the second anvil roll 20, which is downstream of the second continuous sheet supply unit 22 in the rotation direction of the second anvil roll 20 and upstream of the joining device 28 in the rotation direction of the second anvil roll 20. The continuous elastic member supply unit 24 is, for example, a guide roll that has a cylindrical outer peripheral surface with grooves formed at predetermined positions and is rotatably supported. The continuous elastic member supply unit 24 may also be a stationary member that does not rotate.

[0051] The third continuous sheet supply unit 26 supplies the third continuous sheet 8 along the outer peripheral surface 20s of the second anvil roll 20 downstream of the continuous elastic member supply unit 24 in the rotation direction of the second anvil roll 20 and upstream of the joining device 28 in the rotation direction of the second anvil roll 20. The third continuous sheet supply unit 26 is, for example, a rotatably supported guide roll. The third continuous sheet supply unit 26 may also be a non-rotating stationary member, etc.

[0052] The laminate manufacturing apparatus 10 includes a control device 11 that controls the overall operation of the apparatus 10. The control device 11 controls the rotation of the motors that rotate the belt conveyor 12, the cutter roll 14, the first anvil roll 16, and the second anvil roll 20, the opening and closing of the solenoid valve that operates the air cylinder 15, the output of the ultrasonic horn 28, and the like.

[0053] Next, the second anvil roll 20 will be further described with reference to Figures 4 to 8. Figure 4 is a development view of half of the outer peripheral surface 20s of the second anvil roll 20, i.e., a 180° range. Figure 5 is an enlarged view of the main portion of the upper right part of Figure 4, and Figure 6 is an enlarged development view of the main portion continuing from the bottom of Figure 5. Figure 7(a) is a partial enlarged view of the portion indicated by the symbol A in Figure 5, and Figure 7(b) is a partial enlarged view of the portion indicated by the symbol B in Figure 5. Figure 8(a) is a schematic left side view of the second anvil roll 20, Figure 8(b) is a schematic front view of the second anvil roll 20, and Figure 8(c) is a schematic right side view of the second anvil roll 20.

[0054] As shown in Figure 8, the outer peripheral surface 20s of the second anvil roll 20 includes a first region 21a that is continuous around the entire circumference, second and third regions 21b and 21c adjacent to one side of the first region 21a, fourth and fifth regions 21d and 21e adjacent to the other side of the first region 21a, a sixth region 21f adjacent to the second and third regions 21b and 21c, and a seventh region 21g adjacent to the fourth and fifth regions 21d and 21e. The second continuous sheet 4 is disposed in the first region 21a. One sheet piece 3a of a pair of sheet pieces 3a and 3b is disposed in the second region 21b, and the other sheet piece 3b is disposed in the fourth region 21d. The third region 21c and the fifth region 21e correspond to portions of the continuous laminate 9 where the absorbent main body is to be disposed.

[0055] As shown in Figures 4 to 6, the outer peripheral surface 20s of the second anvil roll 20 has a plurality of ridges 31 to 35 formed at predetermined intervals, and as shown in Figures 5 and 6, first suction holes 30a and second absorption holes 30b are formed between adjacent ridges 31 to 35.

[0056] 4 to 6, the ribs 31 to 35 are formed in at least the first to fifth regions 21a to 21e (see FIG. 8) of the outer circumferential surface 20s of the second anvil roll 20. Although the ribs 31 to 35 are shown to be formed so as to extend into the sixth and seventh regions 21f, 21g, the ribs 31 to 35 may not be formed in the sixth and seventh regions 21f, 21g.

[0057] The ribs 31 to 35 are formed in a helical gear shape and twisted along the outer peripheral surface 20s of the second anvil roll 20. That is, as shown in the developed views of Figures 4 to 6, the ribs 31 to 35 are inclined with respect to the generatrix of the outer peripheral surface 20s of the second anvil roll 20 (a line segment that forms the cylindrical outer peripheral surface 20s and is parallel to the rotation axis direction 20z of the second anvil roll 20). For example, as shown in Figure 4, the inclination angle γ of the ribs 31 to 35 with respect to the rotation axis direction 20z of the second anvil roll 20 is 1° or less. The ribs 31 to 35 are formed at equal pitches.

[0058] If the protrusions 31 to 35 extend parallel to the direction of the central axis 20z of rotation of the second anvil roll 20 and are not twisted, the rotation of the second anvil roll 20 also causes the ultrasonic horn 28 to alternate between facing the protrusions 31 to 35 directly and not facing them directly, and when it faces them directly, a joint is formed.

[0059] When the ridges 31 to 35 are twisted, the time that the ultrasonic horn 28 faces the ridges 31 to 35 becomes longer and the time that it does not face them becomes shorter. Also, the area of ​​the portion of the ultrasonic horn 28 that faces the ridges 31 to 35 becomes smaller than when the ridges 31 to 35 are not twisted. Therefore, when the ridges 31 to 35 are twisted, the output of the ultrasonic horn 28 can be made smaller than when the ridges 31 to 35 are not twisted.

[0060] The ridges 31 to 35 are in contact with or close to each other when viewed from the direction of the central axis 20z of rotation of the second anvil roll 20. As a result, when the second anvil roll 20 rotates, the ultrasonic horn 28 always faces one of the ridges 31 to 35, forming a continuous bonded portion, or faces one of the ridges 31 to 35 most of the time, forming a substantially continuous bonded portion.

[0061] 5 and 6, the ribs 31 to 35 are formed with first grooves 71 to 75 along which the first continuous elastic member 5 is aligned, and second grooves 81 to 83 along which the second continuous elastic member 6 is aligned. The first grooves 71 to 75 and the second grooves 81 to 83 are formed at positions away from the first suction holes 30a and the second suction holes 30b in the direction of the central axis 20z of rotation of the second anvil roll 20. The first continuous elastic member 5 and the second continuous elastic member 6 are aligned along the outer peripheral surface 20s of the second anvil roll 20 so as not to overlap with the first suction holes 30a and the second suction holes 30b, and are therefore less susceptible to the influence of suction from the first suction holes 30a and the second suction holes 30b.

[0062] The ridges 31 to 35 are formed with grooves 71 to 75, 81 to 83 and widened portions 32p, 32q in appropriate forms so as to achieve desired characteristics depending on the position on the outer circumferential surface 20s of the second anvil row 20.

[0063] More specifically, a first type first groove 71 and a first type second groove 81 are formed in each of the first protrusions 31 adjacent to both sides of the intended cutting position where the continuous laminate 9 is cut to form the individual absorbent article pieces. As shown in Figure 7(a) , the first protrusions 31 are formed so that the upper surface 31t of the portion adjacent to the first groove 71 or the second groove 81 is slightly higher than the upper surface 31s of the other portion. This results in a higher bonding strength between the sheet pieces 3a, 3b or the second continuous sheet 4 and the third continuous sheet 8 at the portion adjacent to the first continuous elastic member 5 or the second continuous elastic member 6 (the portion corresponding to the upper surface 31t) than at the other portion (the portion corresponding to the upper surface 31s).

[0064] As shown in FIG. 7( b), the two second protrusions 32, 32 adjacent to the first protrusion 31 have widened portions 32p, 32q that are widened in the circumferential direction of the second anvil roll 20, and the second protrusions 32 and the widened portions 32p, 32q have second-type first grooves 72 and second grooves 82 that are longer than the first-type grooves 71, 81. The upper surfaces 32t of the portions adjacent to the first grooves 72 or second grooves 82 are formed slightly higher than the upper surfaces 32s of the remaining portions. This results in a higher bonding strength between the sheet pieces 3a, 3b or the second continuous sheet 4 and the third continuous sheet 8 at the portions adjacent to the first continuous elastic member 5 or second continuous elastic member 6 (portions corresponding to the upper surfaces 32t) than at the remaining portions (portions corresponding to the upper surfaces 32s).

[0065] The third protrusion 33 adjacent thereto has a third type second groove 83 formed in the first region 21a, and a third type first groove 73 formed in the second region 21b and the fourth region 21d.

[0066] However, the two fourth protrusions 34, 34 that pass through the second region 21b and the fourth region 21d and are adjacent to the boundary line with the third region 21c and the fifth region 21e have a fourth type first groove 74 formed in the second region 21b and the fourth region 21d, and a third type second groove 83 formed in the first region 21a.

[0067] The fifth protrusion 35, which passes through the third region 21c and the fifth region 21e, has a fifth type first groove 75 formed in the third region 21c and the fifth region 21e, and a third type second groove 83 formed in the first region 21a.

[0068] Similar to the first and second protrusions 31 and 32, the third to fifth protrusions 33, 34 and 35 have upper surfaces adjacent to the first grooves 73, 74 and 75 or the second groove 83 that are slightly higher than the upper surfaces of other portions.

[0069] The first grooves 71 to 75 and the second grooves 81 to 83 have different configurations depending on the position in the circumferential direction 20x of the second anvil roll 20. In other words, the first grooves 71 to 75 and the second grooves 81 to 83 have appropriate dimensions and cross-sectional shapes so as to bond or not bond the first continuous elastic member 5 and the second continuous elastic member 6 to the sheet pieces 3a, 3b or the second continuous sheet 4 and the third continuous sheet 8 with an appropriate strength depending on the position in the circumferential direction 20x.

[0070] For example, the third type first grooves 73 and third grooves 83 have dimensions and cross-sectional shapes that allow the first continuous elastic member 5 and the second continuous elastic member 6 to be joined with average strength.

[0071] The first type first grooves 71 and second grooves 81 are wider and deeper than the third type first grooves 73 and third grooves 83 so that the first continuous elastic member 5 and the second continuous elastic member 6 are not joined and so that the cut ends of the first continuous elastic member 5 and the second continuous elastic member 6 shrink and recede when the continuous laminate 9 is cut to form individual pieces of the absorbent article.

[0072] The fourth type first groove 74 has a smaller width and / or depth than the third type first groove 73 and third groove 83 in order to strengthen the bond of the first continuous elastic member 5 so that the bond is not destroyed when cutting the first continuous elastic member 5 in the portion that does not overlap the sheet pieces 3a, 3b.

[0073] The second type first grooves 72 and second grooves 82 have a smaller width and / or depth than the third type first grooves 73 and third grooves 83, and their lengths are extended by the widening portions 32p, 32q in order to strengthen the bond between the first continuous elastic member 5 and the second continuous elastic member 6 so that the bond is not destroyed when the continuous laminate 9 is cut at the intended cutting position.

[0074] The fifth type first groove 75 has a size and cross-sectional shape suitable for supporting the first continuous elastic member 5 .

[0075] The first suction holes 30a are formed in the second region 21b and the fourth region 21d on the outer peripheral surface 20s of the second anvil roll 20. The second suction holes 30b are formed outside the second region 21b and the fourth region 21d, in an adjacent region adjacent to the boundary line between the second region 21b and the fourth region 21d.

[0076] Suction from the first suction holes 30a sucks and transports the sheet pieces 3a, 3b to the second region 21b and the fourth region 21d of the outer peripheral surface 20s of the second anvil roll 20. Suction from the second suction holes 30b prevents the sheet pieces 3a, 3b, which are spaced apart and sucked onto the outer peripheral surface 20s of the second anvil roll 20, from turning over. That is, when the second anvil roll 20 is rotating, if airflow disturbances occur around the sheet pieces 3a, 3b being sucked onto the outer peripheral surface 20s of the second anvil roll 20, the sheet pieces 3a, 3b may turn over. Suction from the second suction holes 30b can prevent such airflow disturbances from occurring. Furthermore, if a steady airflow toward the second suction holes 30b hits the peripheral portions of the sheet pieces 3a, 3b and presses them against each other, the sheet pieces 3a, 3b will not turn over.

[0077] The first suction holes 30a and the second suction holes 30b formed in the outer peripheral surface 20s of the second anvil roll 20 may have the same size and / or shape, or may vary depending on their positions. For example, the opening and inner diameter of the second suction holes 30b may be larger than the opening and inner diameter of the first suction holes 30a. The second suction holes 30b may be omitted.

[0078] Next, the operation of the laminate manufacturing apparatus 10 will be described.

[0079] The pair of first continuous sheets 2a, 2b supplied to the outer peripheral surface 16s of the first anvil roll 16 by the first continuous sheet supply unit 12 are sucked and transported onto the outer peripheral surface 16s of the first anvil roll 16. A cutter roll 14 disposed at a cutting position 14p cuts the pair of first continuous sheets 2a, 2b being transported by the first anvil roll 16 to sequentially form a pair of sheet pieces 3a, 3b. The first anvil roll 16 sucks and transports the pair of sheet pieces 3a, 3b, and delivers them to the second anvil roll 20. When delivering the pair of sheet pieces 3a, 3b to the second anvil roll 20, the peripheral speeds of the first anvil roll 16 and the second anvil roll 20 are the same or approximately the same.

[0080] The rotation speed of the first anvil roll 16 is changed so that the rotation speed when the pair of sheet pieces 3 a, 3 b is delivered to the second anvil roll 20 is higher than the rotation speed when the pair of first continuous sheets 2 a, 2 b is cut. As a result, the pair of formed sheet pieces 3 a, 3 b are delivered to the second region 21 b and the fourth region 21 d of the outer circumferential surface 20 s of the second anvil roll 20 with an interval in the conveyance direction.

[0081] The second anvil roll 20 sequentially receives the pair of sheet pieces 3 a, 3 b from the first anvil roll 16, sucks and transports them, and then sucks and transports the second continuous sheet 4 supplied by the second continuous sheet supply unit 22 to the first region 21 a of the outer peripheral surface 20 s, thereby disposing the second continuous sheet 4 between the sheet pieces 3 a, 3 b.

[0082] Next, the continuous elastic member supply section 24 supplies a first continuous elastic member 5 and a second continuous elastic member 6, and the first continuous elastic member 5 overlaps the sheet pieces 3a, 3b being sucked onto the outer peripheral surface 20s of the second anvil roll 20 and transported, and the second continuous elastic member 6 overlaps the second continuous sheet 4 being sucked onto the outer peripheral surface 20s of the second anvil roll 20 and transported.

[0083] Next, the third continuous sheet supply section 26 supplies the third continuous sheet 8, and the third continuous sheet 8 overlaps the sheet pieces 3a, 3b and second continuous sheet 4, the first continuous elastic member 5 and the second continuous member 6 being transported along the second anvil roll 20.

[0084] Next, the joining device 28 cooperates with the protrusions 31 to 35 of the second anvil roll 20 to join the sheet pieces 3a, 3b or the second continuous sheet 4 being transported along the outer peripheral surface 20s of the second anvil roll 20 to the first continuous elastic member 5 or the second continuous member 6 and the third continuous sheet 8 to form a continuous laminate 9.

[0085] For example, in correspondence with the portions of the protrusions 31 to 35 that are away from the grooves 71 to 75 and 81 to 83, a pair of sheet pieces 3a, 3b or the second continuous sheet 4 and the third continuous sheet 8 are joined to each other, and in correspondence with the grooves 72, 73, and 82, the first continuous elastic member 5 or the second continuous member 6 is joined to the sheet pieces 3a, 3b or the second continuous sheet 4 and the third continuous sheet 8.

[0086] The continuous laminate 9 is divided into a pair of continuous laminates along a planned division position 9x indicated by a dashed line 9x in Fig. 2, for example, and used to manufacture absorbent articles. Specifically, the divided pair of continuous laminates are swapped, and both ends of the absorbent main body are joined between adjacent sheet pieces 3a, 3a; 3b, 3b in the conveyance direction, as in the conventional example shown in Fig. 9, and then cut at a predetermined position between the adjacent absorbent main bodies to form individual pieces of absorbent articles.

[0087] In conventional laminate manufacturing apparatuses, two units are required to continuously manufacture absorbent articles, whereas with laminate manufacturing apparatus 10, only one unit is required to continuously manufacture absorbent articles.

[0088] Therefore, the laminate manufacturing apparatus 10 can more efficiently manufacture the continuous laminate 9 for manufacturing worn articles.

[0089] When the cutter roll 14 is moved to the retracted position 14q using the moving device 15, the pair of first continuous sheets 2a, 2b can be supplied to the second anvil roll 20 without being cut by the cutter roll 14. This makes it possible to form a continuous laminate in which the first continuous elastic member 5 and the second continuous elastic member 6 are not exposed in the area where the absorbent main body is to be placed.

[0090] When the laminate manufacturing apparatus 10 starts operating, the cutting device 14 is moved to the cutting position 14p at an appropriate timing in synchronization with the supply of the pair of first continuous sheets 2a, 2b, the second continuous sheet 4, and the third continuous sheet 8, thereby making it possible to manufacture the continuous laminate 9 while suppressing shrinkage in the width direction of the pair of sheet pieces 3a, 3b, the second continuous sheet 4, and the third continuous sheet 8.

[0091] For example, the laminate manufacturing apparatus 10 is started with the cutting device 14 positioned at the retracted position 14q. At this time, the belt conveyor 12 supplies the pair of continuous sheets 2a, 2b to the first anvil roll 16, which then delivers the first continuous sheets 2a, 2b to the second anvil roll 20. The second anvil roll 20 sucks and transports the pair of continuous sheets 2a, 2b, so that the second continuous sheet 4 is placed between the pair of continuous sheets 2a, 2b, the first continuous elastic member 5 overlaps the pair of first continuous sheets 2a, 2b, the second continuous elastic member 6 overlaps the second continuous sheet 4, and the third continuous sheet 8 overlaps the first continuous elastic member 5 and the second continuous elastic member 6, and the joining device 28 forms a joint. The sheets 2a, 2b, 4, and 8 are supplied at the same speed.

[0092] Next, the moving device 15 is operated to move the cutting device 14 to the cutting position 14p, start cutting the pair of first continuous sheets 2a, 2b, and change the rotation speed of the first anvil roll 16 so as to synchronize with the second anvil roll 20. That is, once the pair of first continuous sheets 2a, 2b are cut to form the pair of sheet pieces 3a, 3b, the first anvil roll 16 changes its rotation speed and delivers the pair of sheet pieces 3a, 3b to the second anvil roll 20 so that they are attracted to the second region 21b and fourth region 21d of the outer circumferential surface 20s of the second anvil roll 20.

[0093] Next, the operation is accelerated to a predetermined steady operating speed. During acceleration, the speed at which the belt conveyor 12 feeds the pair of first continuous sheets 2a, 2b is made slightly slower than the speed at which the first anvil roll 16 transports the pair of first continuous sheets 2a, 2b, thereby generating tension in the pair of first continuous sheets 2a, 2b between the belt conveyor 12 and the first anvil roll 16. When the steady operating speed is reached, a predetermined amount of tension is generated in the pair of first continuous sheets 2a, 2b, and the cutter roll 14 and the first anvil roll 16 rotate synchronously, thereby cutting the pair of first continuous sheets 2a, 2b into a pair of sheet pieces 3a, 3b of a predetermined length.

[0094] The pair of first continuous sheets 2a, 2b and the pair of sheet pieces 3a, 3b are sucked onto the outer peripheral surface 16s of the first anvil roll 16, and the pair of sheet pieces 3a, 3b are sucked and transported onto the outer peripheral surface 20s of the second anvil roll 20. By continuing suction in this manner, the pair of sheet pieces 3a, 3b of a predetermined length formed by cutting the pair of first continuous sheets 2a, 2b under tension can be transported while suppressing shrinkage of the pair of sheet pieces 3a, 3b, i.e., shrinkage that occurs when the tension is released.

[0095] By moving the cutting device 14 to the retracted position 14q at an appropriate timing when the laminate manufacturing apparatus 10 is stopped, the laminate manufacturing apparatus 10 can be easily restarted after the operation has stopped. For example, when stopping operation, the apparatus decelerates from a steady operating speed, and while decelerating, the tension on the pair of first continuous sheets 2a, 2b is released. Next, the moving device 15 is operated to move the cutting device 14 to the retracted position 14q, completing the cutting of the pair of first continuous sheets 2a, 2b, and supplying the pair of continuous sheets 2a, 2b to the second anvil roll 20. Next, the speed is reduced and the apparatus is stopped. Since the pair of first continuous sheets 2a, 2b are supplied to the second anvil roll 20 when the apparatus is stopped, operation can be easily restarted.

[0096] <Summary> As described above, the laminate manufacturing apparatus 10 can more efficiently manufacture the continuous laminate 9 for manufacturing worn articles.

[0097] The present invention is not limited to the above-described embodiment, but can be implemented with various modifications.

[0098] For example, instead of the ridges 31 to 35, a plurality of protrusions or the like arranged in a scattered pattern may be formed on the outer peripheral surface 20s of the second anvil roll 20.

[0099] DESCRIPTION OF SYMBOLS 2a, 2b First continuous sheet 3a, 3b Sheet piece 4 Second continuous sheet 5 First continuous elastic member 6 Second continuous elastic member 8 Third continuous sheet 9 Continuous laminate 10 Laminate manufacturing device 12 Belt conveyor (first continuous sheet supply section) 14 Cutter roll (cutting device) 14a Cutter (cutting blade) 14p Cutting position 14q Retracted position 15 Air cylinder (moving device) 16 First anvil roll 16s Outer circumferential surface 20 Second anvil roll 20s Outer circumferential surface 20x Circumferential direction 20z Rotation central axis direction 21b Second region (sheet piece region) 21d Fourth region (sheet piece region) 22 Guide roll (second continuous sheet supply section) 24 Guide roll (continuous elastic member supply section) 26 Guide roll (third continuous sheet supply section) 28 Ultrasonic horn (bonding device) 30a, 30b Suction hole 31-35 Projection (protrusion) 71-75, 81-83 Groove

Claims

1. A cutting device having a cutting edge; a first anvil roll having an outer peripheral surface for sucking and conveying a pair of first continuous sheets with a predetermined interval therebetween, the cutting edge of the cutting device approaching or contacting the outer peripheral surface to cut the pair of first continuous sheets to sequentially form a pair of sheet pieces, the outer peripheral surface sucking the pair of sheet pieces and conveying them at a higher speed than the pair of first continuous sheets; a second anvil roll having an outer peripheral surface formed with a plurality of suction holes and a plurality of protrusions, the outer peripheral surface being arranged to receive the pair of sheet pieces from the first anvil roll, and the outer peripheral surface sucking and conveying the pair of sheet pieces by suction from the suction holes; a joining device arranged to face the outer peripheral surface of the second anvil roll and cooperating with the protrusions of the second anvil roll to form a joining portion; a first continuous sheet supply portion for supplying the pair of first continuous sheets to the outer peripheral surface of the first anvil roll at the upstream side in the rotation direction of the first anvil roll with respect to the cutting device and at the downstream side in the rotation direction of the first anvil roll with respect to the second anvil roll; a second continuous sheet supply portion for supplying a second continuous sheet to the outer peripheral surface of the second anvil roll at the downstream side in the rotation direction of the second anvil roll with respect to the first anvil roll and at the upstream side in the rotation direction of the second anvil roll with respect to the joining device so as to be arranged between the pair of sheet pieces; a continuous elastic member supply portion for supplying a first continuous elastic member to overlap the pair of sheet pieces and a second continuous elastic member to overlap the second continuous sheet toward the outer peripheral surface of the second anvil roll at the downstream side in the rotation direction of the second anvil roll with respect to the continuous elastic member supply portion and at the upstream side in the rotation direction of the second anvil roll with respect to the joining device; and a third continuous sheet supply portion for supplying a third continuous sheet to overlap the first continuous elastic member and the second continuous elastic member toward the outer peripheral surface of the second anvil roll at the downstream side in the rotation direction of the second anvil roll with respect to the third continuous sheet supply portion and at the upstream side in the rotation direction of the second anvil roll with respect to the joining device. A laminate manufacturing apparatus comprising the above components.

2. The laminate manufacturing apparatus according to claim 1, wherein suction holes are formed in a sheet piece region of the outer peripheral surface of the second anvil roll, where the pair of sheet pieces are disposed, and an adjacent region outside the sheet piece region and adjacent to a boundary line of the sheet piece region.

3. The laminate manufacturing apparatus according to claim 1 or 2, wherein a plurality of ridges extending in a chevron gear shape are formed as the protrusions on the outer peripheral surface of the second anvil roll, and when viewed from the direction of the rotation center axis of the second anvil roll, the adjacent ridges are in contact with or close to each other, and suction holes are formed between the adjacent ridges.

4. The laminate manufacturing apparatus according to claim 3, wherein a plurality of grooves intersecting the ridges are formed in the ridges of the second anvil roll, the continuous elastic member supply unit supplies the first continuous elastic member and the second continuous elastic member respectively along any one of the grooves, and the grooves and the suction holes are separated from each other in the direction of the rotation center axis of the second anvil roll.

5. The laminate manufacturing apparatus according to claim 4, wherein the plurality of grooves have different modes according to the circumferential position of the second anvil roll.

6. The laminate manufacturing apparatus according to claim 1, further comprising a moving device that moves the cutting device between a cutting position where the cutting blade of the cutting device approaches or contacts the outer peripheral surface of the first anvil roll to cut the pair of first continuous sheets and a retracted position where the cutting blade of the cutting device is separated from the outer peripheral surface of the first anvil roll and does not cut the pair of first continuous sheets.

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