Apparatus and method for forming a torso enclosure portion for pull-up diaper products

Abstract

An apparatus for manufacturing a torso enclosure for use in the manufacture of a pant-type diaper product includes first and second web infeed assemblies for supplying a first continuous web and a second continuous web, the first continuous web forming a broad first backsheet strip defining a continuous lumbar and leg section and a narrow second backsheet strip defining a continuous lumbar section, the second continuous web forming narrow first and second topsheet strips and a broad third sheet strip.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a body encircling portion for use in manufacturing a pant-type diaper product, and an apparatus for manufacturing the body encircling portion. More specifically, the present invention relates to an apparatus for manufacturing a two-ply body encircling portion having a waist elastic strand fixed by a welding unit without an adhesive, and a non-linearly applied leg elastic strand fixed by an adhesive, and a related method.

Background Art

[0002] For example, wearable absorbent products including adult incontinence products, nighttime pants, training pants, and other pant-type diapers typically incorporate an elasticized body encircling portion that extends around the wearer's waist and is intended to keep the article snug against the wearer during use. The elasticized section is also preferably provided around the leg openings to hold the article snug against the wearer's legs and prevent urine leakage.

[0003] The body encircling portion may incorporate a waist elastic strand, which is sandwiched under tension between an inner layer and an outer layer and is arranged to surround the wearer's waist to provide the necessary elongation, and the leg elastic strand is similarly sandwiched under tension between the inner layer and the outer layer around the leg openings. In such an arrangement, the elastic strands are typically fixed in place between the inner and outer layers of the body encircling portion by an adhesive.

[0004] However, the adhesives used in the manufacture of such torso casings for pull-up diapers are relatively expensive, as a result of the cost of the adhesive and the need for a complex dispensing system to apply the adhesive during manufacturing. Welding has been used as an alternative to fix the waist elastic strands between the inner and outer layers. However, due to the processing challenges associated with welding non-linear elastic strands, welding has not been found to be a reliable alternative to adhesive for fixing the leg elastic strands. Therefore, there is a need for apparatus and methods for manufacturing torso casings for pull-up diapers that leverage the advantages of welding while reducing the additional material costs associated with the use of adhesive. [Overview of the project]

[0005] According to one aspect of the present invention, an apparatus is provided for manufacturing a torso enclosure portion for use in manufacturing a pant-type diaper product, comprising: first and second web infeed assemblies for feeding a first continuous web and a second continuous web in a feeding direction, wherein the first continuous web forms a broad first backsheet strip defining a continuous, aligned waist and leg section extending in the feeding direction, and a narrow second backsheet strip defining a continuous waist section extending in the feeding direction, and the second continuous web forms narrow first and second topsheet strips and a broad third topsheet strip; and a first slitting assembly positioned to receive and slit the first continuous web along a first cutting line extending in the feeding direction in order to separate the first and second backsheet strips. The second slitting assembly is positioned to receive and slit the second continuous web along second and third cutting lines extending in the feeding direction in order to separate the first, second and third topsheet strips. A lumbar elastic infeed is positioned to supply lumbar elastic strands under tension in the supply direction on the lumbar section of the first backsheet strip and on the lumbar section of the second backsheet strip. The first and second lumbar supply assemblies are positioned to orient the first and second topsheet strips to sandwich the lumbar elastic strands between the lumbar section of the first backsheet strip and the first topsheet strip, and between the lumbar section of the second backsheet strip and the second topsheet strip. At least one welding assembly intermittently welds the lumbar section of the first backsheet to the first topsheet in the supply direction to capture the lumbar elastic strands between the lumbar section of the first backsheet and the first topsheet, and intermittently welds the second backsheet strip to the second topsheet in the supply direction to capture the lumbar elastic strands between the second backsheet strip and the second topsheet.An adhesive unit is positioned to apply leg adhesive to the leg sections of the first backsheet strip; a leg elastic infeed is positioned to insert the leg elastic strands under tension in a non-linear pattern onto the leg adhesive, generally in the supply direction; and a leg supply assembly is positioned to cover the first backsheet strip and orient the third topsheet strip to sandwich the leg elastic strands between the third topsheet strip and the first backsheet strip.

[0006] Other preferred features of the apparatus are defined in dependent claims 2 to 12 and will be described further below.

[0007] A method for manufacturing a torso enclosure for use in manufacturing a pant-type diaper product is provided, comprising the steps of: operating first and second web infeed assemblies to feed a first continuous web and a second continuous web in a predetermined feeding direction, wherein the first continuous web forms a broad first backsheet strip defining a continuous, aligned waist and leg section extending in the feeding direction, and a narrow second backsheet strip defining a continuous waist section extending in the feeding direction, and the second continuous web forms narrow first and second topsheet strips and a broad third topsheet strip; operating a first slitting assembly to slit the first continuous web along a first cutting line extending in the feeding direction to separate the first and second backsheet strips; and operating a second slitting assembly to slit the second continuous web along second and third cutting lines extending in the feeding direction to separate the first, second, and third topsheet strips. The method also includes operating a lumbar elastic infeed to supply lumbar elastic strands under tension between the lumbar section of a first backsheet strip and a first topsheet strip, and between the lumbar section of a second backsheet strip and a second topsheet strip; operating at least one welding assembly to intermittently weld the lumbar section of the first backsheet strip to the first topsheet in the supply direction in order to capture the lumbar elastic strands between the lumbar section of the first backsheet strip and a first topsheet, and to intermittently weld the lumbar section of the second backsheet strip to the second topsheet in the supply direction in order to capture the lumbar elastic strands between the lumbar section of the second backsheet strip and a second topsheet; and applying adhesive to the leg elastic strands using an adhesive applicator.The method further includes operating a leg elastic infeed to apply a leg elastic strand nonlinearly with respect to the supply direction under tension between the leg section of a first backsheet strip and a third topsheet strip.

[0008] The apparatus and method of the present invention result in a two-layer structure extending across the waist and leg sections of the torso enclosure, where the waist elastic strands are captured by welding of the waist section, and the non-linearly applied leg elastic strands are fixed by adhesive of the leg section.

[0009] The use of welding in the lumbar section, compared to the use of adhesives, results in a clean and simple mechanism. In contrast to the in-situ joining of adhesives, the elastic strands are captured by welding between the top and bottom sheet strips, resulting in a structure that is less sensitive to temperature and has a softer feel.

[0010] The use of welding to capture elastic strands between the top sheet strip and the back sheet strip utilizes a grooved surface to position the elastic strands for one or more welds. As a result, welding is used with linearly applied strands, as opposed to non-linearly applied elastic strands, such as those required to form elastic leg openings.

[0011] The apparatus and method advantageously avoid the need to attach separate elastic leg sections and the need for additional layers of web material, instead enabling the creation of elastic leg sections integrally formed with the elastic waist section. As a result, the resulting torso enclosure is not very large, allowing for inconspicuous attachment.

[0012] Minimizing the number of layers of material used also has the advantage of reducing the material cost and volume of materials that must be disposed of in landfills and other waste disposal facilities after the articles incorporating the body enclosure have been worn.

[0013] In embodiments of the present invention, the first and second slitting assemblies may be positioned upstream of the lumbar elastic infeed.

[0014] In other embodiments, the second slitting assembly may be positioned upstream of the lumbar elastic infeed, while the first slitting assembly is positioned downstream of at least one welded assembly. In such embodiments, the second continuous web is slit along the second and third cutting lines to separate the first, second and third top sheet strips, in order to allow the placement of the first, second and third top sheet strips relative to the first and second back sheet strips, before slitting the first continuous web along the first cutting line to separate the first and second back sheet strips.

[0015] Preferably, the lumbar elastic strands are inserted so as to extend linearly along each lumbar section in the supply direction, spaced apart from each other in a direction transverse to the supply direction, in order to produce the desired stretching effect.

[0016] The leg elastic strands are preferably inserted so as to extend in a periodic wave pattern along the leg section in the supply direction, enabling evenly spaced cuts of the leg openings in the torso enclosure.

[0017] When the torso section is used to form a pant-style diaper, in order to provide neat edges and improve comfort in the waist section, the outer edges of each of the first and second backsheet strips may be folded during the step of inserting and tucking in the waist elastic strand, so that each topsheet strip covers the folded edges of each backsheet strip.

[0018] In other embodiments, the outer edges of the first and second backsheet strips may be folded after the step of inserting and clamping the waist elastic strands, but before welding, so that the folded edges of each backsheet strip cover the outer edges of the respective topsheet strips.

[0019] In yet another embodiment, the outer edges of the first and second backsheet strips may be folded after welding and joined with adhesive to cover the outer edges of the respective topsheet strips.

[0020] Preferably, in order to improve the comfort and fit of the pant-type diaper formed from the resulting torso surround portion, the method further includes the step of inserting an abdominal elastic strand, which extends under tension in the supply direction, between the leg section of the first backsheet strip and the third topsheet strip, and joining them with an adhesive.

[0021] In such embodiments, the abdominal elastic strands are preferably inserted and joined so as to extend substantially linearly along each leg section in the supply direction, and are equidistant from each other in a direction transverse to the supply direction to provide a uniform stretching effect.

[0022] To avoid exposure of the adhesive in the resulting body enclosure portion, the inner edge of the third top sheet strip is preferably positioned to cover and bond to the inner edge of the first top sheet strip.

[0023] The method may include the step of supplying the first and second continuous webs from a single roll of material arranged to deliver a single continuous feeder web in the supply direction, which is slit along a fourth cutting line extending in the supply direction to form the first and second continuous webs.

[0024] In other embodiments, the method may include the step of supplying first and second continuous webs from a single roll of material arranged to feed continuous feed webs slit along first, second, and third cutting lines in the feeding direction in order to form first and second backsheet strips and first, second, and third topsheet strips.

[0025] In a particularly preferred embodiment, the first and second continuous webs are formed from a nonwoven thermoplastic material, and the welding step is carried out by ultrasonic welding.

[0026] Preferably, in such embodiments of the present invention, the step of welding the waist sections of the first and second backsheet strips to the respective topsheet strip and waist elastic strand includes supplying the waist elastic strand, sandwiched between the respective topsheet strip and backsheet strip, between at least one blade-type horn having a grooved work surface and at least one opposing anvil having a smooth or grooved work surface. The waist elastic strand is supplied under tension between the work surface of the horn and the work surface of the anvil. The respective top and backsheet strips are then welded to each other via welding resulting from intermittently fixing (i.e., capturing) the elastic strand in a predetermined position relative to the top and backsheet strips in the supply direction.

[0027] In the embodiment, one or more rotary or bladed ultrasonic horns having smooth or grooved work surfaces may be used in combination with one or more opposing anvils having grooved work surfaces, such that the waist elastic strands are supplied under tension in the supply direction between grooves formed on the work surface of the anvil and any grooves on the work surface of the horn, so that the top and backsheet strips on both sides of each waist elastic strand are intermittently welded to each other in the supply direction.

[0028] When the working surfaces of the horn and anvil engage a sheet positioned on both sides of the elastic strand to melt the elastic strand, at least partially enclose the elastic strand, and / or frictionally engage the elastic strand at a predetermined position relative to the opposing sheet welds, a fixed weld is formed. The resulting fixed welds are arranged on both sides of a given elastic strand and may, in some embodiments, be a pair of welds that partially overlap the given elastic strand or a single weld or pair of welds that extends at least across the width of the elastic strand. Fixing (i.e., capturing) the waist elastic strand to the opposing sheets provides the necessary elasticity in the waist section of the resulting body surrounding portion.

[0029] The system can be better understood by reference to the following drawings and description. The components in the figures are not necessarily to scale, instead focusing on explaining the disclosed principles. Further, in the drawings, like reference numerals indicate corresponding parts throughout the various figures.

[0030] Here, preferred embodiments of the present invention will be described by way of example with reference to the accompanying drawings.

Brief Description of the Drawings

[0031] [Figure 1] FIG. showing a pant diaper product incorporating an elasticized body surrounding portion according to an embodiment of the present invention.

[0032] [Figure 2A] Cross-sectional view of the elasticized body surrounding portion of the pant diaper product shown in FIG. 1. [Figure 2B] Cross-sectional view of the elasticized body surrounding portion of the pant diaper product shown in FIG. 1.

[0033] [Figure 3] Schematic diagram of steps of a method for manufacturing an elasticized body surrounding portion according to an embodiment of the present invention.

[0034] [Figure 4] This is a schematic diagram of an apparatus for manufacturing an elastic fuselage enclosure portion according to one embodiment of the present invention.

[0035] [Figure 5] This is a schematic diagram of the steps for manufacturing an elasticated fuselage enclosure according to another embodiment of the present invention.

[0036] [Figure 6] This is a schematic diagram of an apparatus for manufacturing an elasticated fuselage enclosure portion according to another embodiment of the present invention. [Modes for carrying out the invention]

[0037] Figures 1, 2A, and 2B show a pant-type diaper product 10 incorporating first and second elastic torso surrounds 12 and 14 manufactured according to one embodiment of the present invention.

[0038] The first and second torso surrounds 12 and 14 each define a waist region 16. The first torso surround 12 further includes a leg region 18 formed integrally with each waist region 16, the leg region 18 having curved edges 20 and 22 separated by a relatively straight edge 21 so as to extend around the wearer's legs when the diaper product 10 is worn.

[0039] Referring to Figure 2A, it can be seen that the lumbar region 16 of the first torso enclosure portion 12 includes a plurality of lumbar elastic strands 24 sandwiched between the lumbar section 26a of the first backsheet strip 26 and the first topsheet strip 28. The lumbar elastic strands 24 are arranged to extend over all or substantially all of the width W of the lumbar region 16. The lumbar elastic strands 24 may be spaced equidistant from each other in the lateral direction T with respect to the width W, or they may be spaced at different distances from each other according to the design specifications.

[0040] The lumbar section 26a of the first backsheet strip 26 and the first topsheet strip 28 are welded to each other on both sides of the lumbar elastic strand at their respective positions so as to fix or hold the lumbar elastic strand 24 in place relative to the first backsheet strip 26 and the first topsheet strip 28 at intermittent positions along the length of the lumbar elastic strand 24.

[0041] Similarly, as shown in Figure 2B, the lumbar region 16 of the second torso enclosure 14 includes a plurality of lumbar elastic strands 24 sandwiched between the lumbar section 30a of the second backsheet strip 30 and the second topsheet strip 32. Similar to the lumbar region 16 of the first torso enclosure 12, the lumbar elastic strands 24 are arranged to extend over all or substantially all of the width W of the lumbar region 16 and may be equidistant from each other or at various distances laterally T with respect to the width W.

[0042] The lumbar section 30a of the second backsheet strip 30 and the second topsheet strip 32 are welded to each other on both sides of the lumbar elastic strand at their respective positions so as to fix or hold the lumbar elastic strand 24 in place relative to the second backsheet strip 30 and the second topsheet strip 32 at intermittent positions along the length of the lumbar elastic strand 24.

[0043] The leg region 18 of the first torso enclosure 12 includes a plurality of leg elastic strands 36 sandwiched between the leg section 26b of the first backsheet strip 26 and the third topsheet strip 40, the leg elastic strands 36 being arranged to follow the contours of the curved edges 20, 22 of the leg region 18 in one exemplary embodiment. The leg elastic strands 36 are bonded in place by an adhesive 38 provided between the leg section 26b of the first backsheet strip 26 and the third topsheet strip 40.

[0044] In the embodiments shown in Figures 1, 2A, and 2B, a plurality of abdominal elastic strands 42 are also sandwiched between the leg section 26b of the first backsheet strip 26 and the third topsheet 40 by adhesive 38. The abdominal elastic strands 42 are arranged to extend over all or substantially all of the width W of the leg region 18 and may be spaced equidistant from each other in the lateral direction T with respect to the width W, or they may be spaced at variable intervals. In other embodiments, the abdominal elastic strands 42 may be omitted.

[0045] To provide smooth finished edges to the respective waist regions 16 of the first and second torso enclosing portions 12 and 14, the outer edge 26c of the first backsheet strip 26 is folded over the outer edge 28c of the first topsheet strip 28 and captured between them. Similarly, the outer edge 30c of the second backsheet strip 30 is folded over the outer edge 32c of the second topsheet strip 32 and captured between them.

[0046] In the embodiments shown in Figures 1, 2A, and 2B, the outer edges 26c and 30c of the first and second backsheet strips 26 and 30 are fixed in place by welding at intermittent positions along the length of the elastic waist strand 24 sandwiched between the outer edges 26c and 30c and the respective backsheet strips 26 and 30.

[0047] In other embodiments, the outer edges 26c, 30c may be folded over the outer edges 28c, 32c of the respective top sheet strips 28, 32 and secured in place with adhesive.

[0048] Although product 10 is shown in an open form in Figure 1 for clarity, it will be understood that the first fuselage enclosure portion 12 and the second fuselage enclosure portion 14 are joined together at the side seam regions 26d and 30d of the finished product 10. The side seam regions 26d and 30d may be fixed by adhesive or ultrasonic welding.

[0049] During use, the top sheet strips 28, 32, and 38 define the skin contact surface of the diaper product 10, while the back sheet strips 26 and 30 define the outer surface of the diaper product 10. The back and top sheet strips 26, 28, 32, and 38 are preferably formed from a nonwoven fabric material.

[0050] Preferably, the third top sheet 32 ​​is positioned to cover the leg section 26b of the first back sheet strip 26, so that the inner edge 32e of the third top sheet 32 ​​covers the inner edge 28e of the first top sheet strip 28. This ensures that no adhesive is exposed on the outer skin contact surface of the resulting torso enclosure portion 12.

[0051] As shown in Figure 1, the first and second torso enclosures 12 and 14 are bridged by a crotch portion 46, one end of which is connected to the leg region 18 of the first torso enclosure 12, and the other end of which is connected to the waist region 16 of the second torso enclosure 14. The crotch portion 46 includes a liquid-absorbing layer on its upper surface 46a and an outer liquid-impermeable layer on its lower side (not shown).

[0052] The elasticity provided by the lumbar elastic strand 24 and the abdominal elastic strand 42 may be deactivated in these areas (i.e., cut or otherwise treated to reduce the elasticity therein) to prevent bunching of the groin area 46.

[0053] Here, a method and apparatus for forming the first and second fuselage enclosing portions 12 and 14 will be explained with reference to Figure 3 and the apparatus 100 shown in Figure 4.

[0054] As a first step, the first and second continuous webs 50 and 52 of the nonwoven material are supplied in a predetermined mechanical feeding direction F by the first and second web infeed assemblies 51 and 53.

[0055] The first continuous web 50 is slit by a first slitting assembly 60, which includes one or more knives, blades, or other cutting devices, along a first cutting line 54 extending in the supply direction F, in order to form the first and second backsheet strips 26, 30. The first cutting line 54 is positioned relative to the width of the first continuous web 50, so that the first backsheet strip 26 is wider than the second backsheet 30 and defines the second backsheet strip 30 which defines the continuous lumbar and leg sections 26a, 26b extending in the supply direction F, and the continuous lumbar section 30a extending in the supply direction F.

[0056] The first and second backsheet strips 26, 30 are positioned adjacent to but separated from each other in a direction T lateral to the supply direction F (i.e., traversing the machine), and are oriented downstream of the slitting assembly 60 by one or more web spreaders 62, 64 such that the leg section 26b of the first backsheet 26 is positioned between the waist sections 26a and 30a.

[0057] The second continuous web 52 is slit by a second slitting assembly 66, which includes one or more knives, blades or other cutting devices, along second and third cutting lines 56, 58 extending in the supply direction F, in order to form the first and second top sheet strips 28, 32 and the third top sheet strip 40. The second and third cutting lines 56, 58 are positioned relative to the width of the second continuous web 52, so that the third top sheet strip 40 is wider than the first and second top sheet strips 28, 32.

[0058] A lumbar elastic infeed in the form of a harp 68 inserts lumbar elastic strands 24 that extend under tension in the supply direction F so as to cover the lumbar section 26a of the first backsheet strip 26 and the lumbar section 30a of the second backsheet strip 30. The harp 68 supplies the lumbar elastic strands 24 substantially linearly in the supply direction F along the lumbar sections 26a and 30a of the first and second backsheet strips 26 and 30. The lumbar elastic strands 24 may be spaced equidistant in the direction T across the supply direction F, or they may be supplied at intervals that vary in the lateral direction T, according to the product design specifications.

[0059] Next, the first and second backsheet strips 26, 30 pass through one or more lumbar edge folding units 84 to fold the outer edges 26c, 30c of the lumbar sections 26a, 30a of the first and second backsheet strips 26, 30 so as to cover the outermost lumbar elastic strand 24.

[0060] Next, the first top sheet strip 28 is oriented via the first lumbar supply assembly 70 to cover the lumbar section 26a of the first back sheet strip 26, sandwiching the lumbar elastic strand 24 between the lumbar section 26a of the first back sheet strip 26 and the first lumbar supply assembly 70. The second top sheet strip 32 is oriented via the second lumbar supply assembly 72 to cover the lumbar section 30a of the second back sheet strip 30, sandwiching the lumbar elastic strand 24 between the lumbar section 30a of the second back sheet strip 30 and the second lumbar supply assembly 72. The first and second top sheet strips 28 and 32 cover the outer edges 26c and 30c.

[0061] To secure the lumbar sections of each top and back sheet together and to hold the folded outer edges 26c, 30c and the lumbar elastic strands 24 in place, the lumbar sections of each top and back sheet, as well as the lumbar elastic strands 24 sandwiched between them, are supplied through at least one welded assembly 74.

[0062] At least one welding assembly 74 may be any known mechanical joining system, including, in non-limiting examples, a thermal welding system, a pressure welding system, a rotary ultrasonic welding system, or a blade ultrasonic welding system, any of which includes one or more components that cooperate to weld (i.e., fuse) the top and back sheets together. In one embodiment, the welding assembly 74 is provided in the form of an ultrasonic joining system having one or more bladed horns 73, also known as sonotrodes, having grooved work surfaces 77 that cooperate with one or more opposing anvils 75 having smooth or grooved ridges 79. In other embodiments, the welding assembly 74 may be provided in the form of an ultrasonic joining system including one or more rotary or bladed horns having either smooth or grooved work surfaces, and one or more anvils having grooved ridges. The welded assembly 74, and the corresponding horn and anvil elements 73 and 75, are referred to in the singular below, but any of the embodiments described may include multiple welded assemblies, each containing one or more horn and / or anvil components.

[0063] The respective lumbar sections of the top and back sheets, as well as the lumbar elastic strands 24, are supplied through the welding assembly 74, thereby aligning the lumbar elastic strands 24 with grooves formed on the working surface of the ultrasonic horn under tension in the supply direction F. As the respective lumbar sections of the top and back sheets, as well as the lumbar elastic strands 24, are supplied through the welding assembly 74, the intermittent operation of the ultrasonic horn 73 forms welds 34 at intermittent positions along the length of the lumbar elastic strands 24.

[0064] The operation of the ultrasonic horn 73 melts the nonwoven material of the respective top and back sheet strips at the contact point between the horn 73 and the anvil 75, resulting in the formation of a weld 34 between the respective top sheet strip and back sheet strip, which aligns with the land surface between the grooves on the working surface of the ultrasonic horn 73, thereby capturing the waist elastic strand 24.

[0065] After the lumbar section is welded to capture the lumbar elastic strand 24 and the lumbar region 16 is formed, the leg section 26b of the first backsheet strip 26 passes through an adhesive unit 76 that applies adhesive 38 to the exposed surface of the leg section 26b of the first backsheet strip 26. Optionally, the apparatus 100 may include one or more web guides and / or spreaders (not shown) positioned downstream of the welded assembly 74 to reposition the welded top and backsheet webs for subsequent downstream processing after they have left the welded assembly 74.

[0066] The leg elastic infeed in the form of a curved leg elastic laydown unit 78 inserts a leg elastic strand 36 extending under tension substantially in the supply direction F and applies the leg elastic strand 36 to the adhesive 38 along the leg section 26b in the supply direction F in a periodic wave pattern or other nonlinear pattern. It will be understood that the curved leg elastic laydown unit 78 can be controlled to change the shape defined by the leg elastic strand 36 on the leg section 26b of the first backsheet strip 26, depending on the intended end use of the fuselage enclosure portions 12, 14.

[0067] The abdominal elastic infeed 80 may be positioned downstream (as shown) or upstream of the curved leg elastic laydown unit 78 to insert an abdominal elastic strand 42 extending under tension in the supply direction F onto the adhesive 38 of the leg section 26b of the first backsheet strip 26. The abdominal elastic infeed 80 supplies the abdominal elastic strand 42 substantially linearly in the supply direction F along the leg section 26b of the first backsheet 26 and is equidistant in the direction T across the supply direction F. In other embodiments, the abdominal elastic strand 42 and the associated abdominal elastic infeed 80 may be omitted.

[0068] Next, the third top sheet strip 40 is oriented via the leg supply assembly 82 to cover the leg section 26b of the first back sheet strip 26, sandwiching the leg elastic strands 24 and the abdominal elastic strands 42 between the leg section 26b of the first back sheet strip 26 and the leg supply assembly 82, and the third top sheet strip 40 is bonded to the leg section 26b of the first back sheet strip 26 by adhesive 38. Optionally, a second bonding unit 76a is provided for applying adhesive 38a to the third top sheet strip 40.

[0069] Preferably, the third top sheet 32 ​​is positioned to cover the leg section 26b of the first backsheet strip 26, so that the inner edge 32e of the third top sheet 32 ​​covers the inner edge 28e of the first topsheet strip 28. This ensures that no adhesive is exposed on the outer skin contact surface of the resulting torso enclosure portion 12. It will be understood that the position of the waist edge folding unit 84 can be changed.

[0070] In another embodiment, the waist edge folding unit 84 may be positioned downstream of the first and second waist supply assemblies 70, 72, so that the folded outer edges 26c, 30c of the first and second backsheet strips 26, 30 cover the respective topsheet strips 28, 32 before passing through the welding assembly 74. In yet another embodiment, the waist edge folding unit 84 may be positioned downstream of the welding assembly 74, so that the folded outer edges 26c, 30c of the first and second backsheet strips 26, 30 cover the respective topsheet strips 28, 32, and adhesive is applied to join them in place.

[0071] The first and second web infeed assemblies 51, 53 and the first and second slitting assemblies 60, 66 are shown in Figure 4 and are positioned linearly with respect to the lumbar elastic infeed. In other embodiments, the first and second web infeed assemblies 51, 53 and the first and second slitting assemblies 60, 66 may be positioned nonlinearly with respect to the lumbar elastic infeed.

[0072] Here, an alternative method for forming the first and second fuselage enclosing portions 12 and 14 will be explained with reference to Figure 5 and the apparatus 100 shown in Figure 6.

[0073] As a first step, the first and second continuous webs 50 and 52 of the nonwoven material are supplied in a predetermined mechanical feeding direction F by the first and second web infeed assemblies 51 and 53.

[0074] A lumbar elastic infeed in the form of a harp 68 inserts lumbar elastic strands 24 that extend in the supply direction F under tension so as to cover the lumbar sections 26a, 30a of the first continuous web 50. The harp 68 supplies the lumbar elastic strands 24 substantially linearly in the supply direction F along the lumbar sections 26a, 30a. The lumbar elastic strands 24 may be spaced equidistant in the direction T across the supply direction F, or they may be supplied at intervals that vary in the lateral direction T, according to the product design specifications.

[0075] Next, the first continuous web 50 passes through one or more lumbar edge folding units 84 to fold the outer edges 26c, 30c of the lumbar sections 26a, 30a of the first continuous web 50 so as to cover the outermost lumbar elastic strand 24.

[0076] The second continuous web 52 is slit by a second slitting assembly 66, which has one or more knives, blades or other cutting devices, along second and third cutting lines 56, 58 extending in the supply direction F, in order to form the first and second top sheet strips 28, 32 and the third top sheet strip 40. The second and third cutting lines 56, 58 are positioned relative to the width of the second continuous 52, so that the third top sheet strip 40 is wider than the first and second top sheet strips 28, 32.

[0077] Next, the first top sheet strip 28 is oriented via the first lumbar supply assembly 70 to cover the lumbar section 26a of the first continuous web 50 so as to sandwich the lumbar elastic strand 24 between the lumbar section 26a of the first continuous web 50 and the first lumbar supply assembly 70, and the second top sheet strip 32 is oriented via the second lumbar supply assembly 72 to cover the lumbar section 30a of the first continuous web 50 so as to sandwich the lumbar elastic strand 24 between the lumbar section 30a of the first continuous web 50 and the second lumbar supply assembly 72. The first and second top sheet strips 28 and 32 cover the outer edges 26c and 30c.

[0078] To secure the lumbar sections of each top and back sheet together and to hold the folded outer edges 26c, 30c and the lumbar elastic strands 24 in place, the lumbar sections of each top and back sheet, as well as the lumbar elastic strands 24 sandwiched between them, are supplied through at least one welded assembly 74.

[0079] At least one welding assembly 74 may be any known mechanical joining system, including, in non-limiting examples, a thermal welding system, a pressure welding system, a rotary ultrasonic welding system, or a blade ultrasonic welding system, any of which includes one or more components that cooperate to weld (i.e., fuse) the top and back sheets together. In one embodiment, the welding assembly 74 is provided in the form of an ultrasonic joining system having one or more bladed horns 73, also known as sonotrodes, having grooved work surfaces 77 that cooperate with one or more opposing anvils 75 having smooth or grooved ridges 79. In other embodiments, the welding assembly 74 may be provided in the form of an ultrasonic joining system including one or more rotary or bladed horns having either smooth or grooved work surfaces, and one or more anvils having grooved ridges. The welded assembly 74, and the corresponding horn and anvil elements 73 and 75, are referred to in the singular below, but any of the embodiments described may include multiple welded assemblies, each containing one or more horn and / or anvil components.

[0080] The respective lumbar sections of the top and back sheets, as well as the lumbar elastic strands 24, are supplied through the welding assembly 74, thereby aligning the lumbar elastic strands 24 with grooves formed on the working surface of the ultrasonic horn under tension in the supply direction F. As the respective lumbar sections of the top and back sheets, as well as the lumbar elastic strands 24, are supplied through the welding assembly 74, the intermittent operation of the ultrasonic horn 73 forms welds 34 at intermittent positions along the length of the lumbar elastic strands 24.

[0081] The operation of the ultrasonic horn 73 melts the nonwoven material of the respective top and back sheet strips at the contact point between the horn 73 and the anvil 75, resulting in the formation of a weld 34 between the respective top sheet strip and back sheet strip, which aligns with the land surface between the grooves on the working surface of the ultrasonic horn 73, thereby capturing the waist elastic strand 24.

[0082] After capturing the lumbar elastic strands 24 and welding the lumbar sections to form the lumbar region 16, the first continuous web 50 is slit by a first slitting assembly 60, which includes one or more knives, blades or other cutting devices, along a first cutting line 54 extending in the supply direction F, to form the first and second backsheet strips 26, 30. The first cutting line 54 is positioned relative to the width of the first continuous web 50, thereby defining the first backsheet strip 26, which is wider than the second backsheet 30, and the second backsheet strip 30, which defines the continuous lumbar and leg sections 26a, 26b extending in the supply direction F, and the continuous lumbar section 30a extending in the supply direction F. One or more web guides and / or spreaders 62, 24 are positioned downstream of the welding assembly 74 to reposition the welded top and backsheet webs laterally (i.e., across the machine) T relative to the feed direction F for subsequent downstream processing after they have left the welding assembly 74. In an alternative embodiment, the first slitting assembly 60 is positioned upstream of the welding assembly 74.

[0083] Next, the leg section 26b of the first backsheet strip 26 passes through an adhesive unit 76 that applies adhesive 38 to the exposed surface of the leg section 26b of the first backsheet strip 26.

[0084] The leg elastic infeed in the form of a curved leg elastic laydown unit 78 inserts a leg elastic strand 36 extending under tension substantially in the supply direction F and applies the leg elastic strand 36 to the adhesive 38 along the leg section 26b in the supply direction F in a periodic wave pattern or other nonlinear pattern. It will be understood that the curved leg elastic laydown unit 78 can be controlled to change the shape defined by the leg elastic strand 36 on the leg section 26b of the first backsheet strip 26, depending on the intended end use of the fuselage enclosure portions 12, 14.

[0085] The abdominal elastic infeed 80 may be positioned downstream (as shown) or upstream of the curved leg elastic laydown unit 78 to insert an abdominal elastic strand 42 extending under tension in the supply direction F onto the adhesive 38 of the leg section 26b of the first backsheet strip 26. The abdominal elastic infeed 80 supplies the abdominal elastic strand 42 substantially linearly in the supply direction F along the leg section 26b of the first backsheet 26 and is equidistant in the direction T across the supply direction F. In other embodiments, the abdominal elastic strand 42 and the associated abdominal elastic infeed 80 may be omitted.

[0086] Next, the third top sheet strip 40 is oriented via the leg supply assembly 82 to cover the leg section 26b of the first back sheet strip 26, sandwiching the leg elastic strands 24 and the abdominal elastic strands 42 between the leg section 26b of the first back sheet strip 26 and the leg supply assembly 82, and the third top sheet strip 40 is bonded to the leg section 26b of the first back sheet strip 26 by adhesive 38. Optionally, a second bonding unit 76a is provided for applying adhesive 38a to the third top sheet strip 40.

[0087] Preferably, the third top sheet 32 ​​is positioned to cover the leg section 26b of the first backsheet strip 26, so that the inner edge 32e of the third top sheet 32 ​​covers the inner edge 28e of the first topsheet strip 28. This ensures that no adhesive is exposed on the outer skin contact surface of the resulting torso enclosure portion 12. It will be understood that the position of the waist edge folding unit 84 can be changed.

[0088] In another embodiment, the waist edge folding unit 84 may be positioned downstream of the first and second waist supply assemblies 70, 72, so that the folded outer edges 26c, 30c of the first and second backsheet strips 26, 30 cover the respective topsheet strips 28, 32 before passing through the welding assembly 74. In yet another embodiment, the waist edge folding unit 84 may be positioned downstream of the welding assembly 74, so that the folded outer edges 26c, 30c of the first and second backsheet strips 26, 30 cover the respective topsheet strips 28, 32, and adhesive is applied to join them in place.

[0089] The first and second web infeed assemblies 51, 53 and the first and second slitting assemblies 60, 66 are shown in Figure 6 and are positioned linearly with respect to the lumbar elastic infeed. In other embodiments, the first and second web infeed assemblies 51, 53 and the first and second slitting assemblies 60, 66 may be positioned nonlinearly with respect to the lumbar elastic infeed.

[0090] In other embodiments, a supply web infeed assembly (not shown) may be positioned upstream of the first and second web infeed assemblies 51, 53 to feed a single continuous feeder web in the feeding direction. In such embodiments, a third slitting assembly may be positioned between the supply web infeed assembly and the first and second web infeed assemblies 51, 53 and slit the feeder web along a fourth cutting line extending in the feeding direction F to provide the first and second continuous webs 50, 52 for feeding through the first and second web supply assemblies 51, 53.

[0091] In other embodiments, a supply web infeed assembly (not shown) may be positioned upstream of the first and second web infeed assemblies 51, 53 to feed a single continuous feeder web in the supply direction.

[0092] In yet another embodiment, the first and second web infeed assemblies 51, 53 may be provided in the form of a single supply web infeed assembly that supplies the first and second continuous webs 50, 52 in the supply direction in the form of a single supply web slit by the first and second slitting assemblies 60, 66, or in the form of a single slitting assembly (not shown) that replaces the first and second slitting assemblies 60, 66 along first, second, and third cutting lines 54, 56, 58 extending in the supply direction F to form the first and second backsheet strips 26, 30 and the first, second, and third topsheet strips 28, 32, 40.

[0093] In yet another embodiment, the first and second web infeed assemblies 51, 53, and one or more additional web infeed assemblies (not shown) may supply webs originally sized to the widths of the first backsheet strip 26, the second backsheet strip 30, the first topsheet strip 28, the second topsheet strip 32, and / or the third topsheet strip 40, so that the first and / or second slitting assemblies may be omitted.

[0094] Further processing of the intermediate torso enclosing portion of the pant-type diaper product can be performed downstream of apparatus 100 in Figure 4 or Figure 6 using equipment and processes known in the art. Details of such additional equipment are outside the scope of the present invention, but those skilled in the art will recognize that such equipment may include, along with additional processing units known in the art, any combination of all or some of the exemplary processing units, such as a deactivation unit 92, a transfer unit 94 (optionally having a cutting function) for handling absorbent inserts 46, a cutting unit 96 for cutting a portion of the waistband to create a curved leg profile, a folding unit 98 in which one of the first and second torso enclosures 12, 14 is folded over the other, one or more adhesive or ultrasonic bonding units 102 in which the first and second torso enclosures 12, 14 are joined together at the side seam regions 26d, 30d, a cutting or knife unit 104 for separating the continuous web of the intermediate pant product into individual products 10, and / or a transfer unit 106 for picking up the individual products 10 and rotating them in the packaging direction, and may further represent a packaging folding unit for folding the individual products 10 for packaging.

[0095] Embodiments of the present invention will be described in the following numbered paragraphs. 1. Apparatus for manufacturing a torso surround for use in the manufacture of a pant-type diaper product, comprising first and second web infeed assemblies (51, 53) for supplying a first continuous web and a second continuous web (50, 52) in a supply direction (F), wherein the first continuous web forms a broad first backsheet strip defining a continuous, aligned waist and leg section extending in the supply direction, and a narrow second backsheet strip defining a continuous waist section extending in the supply direction, and the second continuous web forms a narrow first and First and second web infeed assemblies (51, 53) forming two top sheet strips and a broad third top sheet strip; a first slitting assembly (60) positioned to receive and slit a first continuous web along a first cutting line extending in the supply direction in order to separate the first and second back sheet strips; and a second continuous web positioned to receive and slit a second continuous web along second and third cutting lines extending in the supply direction in order to separate the first, second, and third top sheet strips. A second slitting assembly (66) positioned to supply lumbar elastic strands under tension in the supply direction on the lumbar section of the first backsheet strip and on the lumbar section of the second backsheet strip; first and second lumbar supply assemblies (70, 72) positioned to orient the first and second topsheet strips to sandwich lumbar elastic strands between the lumbar section of the first backsheet strip and the first topsheet strip, and between the lumbar section of the second backsheet strip and the second topsheet strip; at least one welding assembly (74) intermittently welds the lumbar section of the first backsheet to the first topsheet in the supply direction to capture lumbar elastic strands between the lumbar section of the first backsheet and the first topsheet, and intermittently welds the second backsheet strip to the second topsheet in the supply direction to capture lumbar elastic strands between the second backsheet strip and the second topsheet;The apparatus comprises: an adhesive unit (76) positioned to apply leg adhesive to the leg sections of a first backsheet strip; a leg elastic infeed (78) positioned to insert leg elastic strands under tension onto the leg adhesive in a non-linear pattern, generally in the supply direction; and a leg supply assembly (82) positioned to cover the first backsheet strip and to orient the third topsheet strip so as to sandwich the leg elastic strands between the first backsheet strip and the third topsheet strip. 2. The apparatus according to paragraph 1, wherein the first and second slitting assemblies (60, 66) are both positioned upstream of the lumbar elastic infeed (68). 3. The apparatus according to paragraph 1, wherein a second slitting assembly is positioned upstream of a lumbar elastic infeed (68), and a first slitting assembly (60) is positioned downstream of at least one welding assembly (74). 4. The apparatus according to any one of paragraphs 1 to 3, wherein the leg elastic infeed includes one or more reciprocating leg elastic infeed elements for inserting the leg elastic strands so as to extend in a periodic wave pattern along the leg section in the supply direction. 5. The apparatus according to any one of paragraphs 1 to 4, further comprising one or more waist edge folding units (84) positioned downstream of the waist elastic infeed assembly upstream of the second waist supply assembly for folding the respective outer edges of the first and second backsheet strips, thereby covering the folded edges of each backsheet strip before each topsheet strip moves through the welding assembly in the supply direction. 6. The apparatus according to any one of paragraphs 1 to 4, further comprising a lumbar supply assembly and one or more lumbar edge folding units (84) located downstream of the second lumbar supply assembly for folding the respective outer edges of the first and second backsheet strips, thereby ensuring that the folded edges of each backsheet strip cover the outer edges of the respective topsheet strips. 7. The apparatus according to any one of paragraphs 1 to 6, further comprising a ventral elastic infeed (80) positioned upstream of the leg supply assembly in the supply direction and arranged to insert a ventral elastic strand extending under tension in the supply direction onto the adhesive of the leg section of the first backsheet strip, wherein the leg supply assembly orients the third top sheet strip to cover the leg section of the first backsheet strip, sandwiching the leg elastic strand and the ventral elastic strand between the third top sheet strip and the leg section of the first backsheet strip. 8. The apparatus according to any one of paragraphs 1 to 6, further comprising one or more web spreaders (62, 64) for arranging the first and second backsheet strips adjacent to but separated from each other in a direction transverse to the supply direction, and positioning the leg section of the first backsheet strip between the waist sections. 9. The apparatus according to any one of paragraphs 1 to 8, wherein the welding assembly comprises at least one blade-type ultrasonic horn having a grooved work surface and at least one opposing anvil having a smooth or grooved ridge, the horn and anvil being positioned on either side of a supply path through the welding assembly, thereby causing a lumbar elastic strand to be sandwiched between a lumbar section of a first backsheet and a first topsheet, and between a lumbar section of a second backsheet and a second topsheet, and to move between the horn and anvil in the supply direction. 10. The apparatus according to any one of paragraphs 1 to 8, wherein the welding assembly comprises at least one rotary or blade-type ultrasonic horn having a smooth or grooved working surface, and at least one opposing anvil having a grooved ridge, the horn and anvil being positioned on either side of a feed path through the welding assembly, thereby causing a lumbar elastic strand to be sandwiched between a lumbar section of a first backsheet and a first topsheet, and between a lumbar section of a second backsheet and a second topsheet, and to move in the feed direction between the horn and anvil. 11. The apparatus according to any one of paragraphs 1 to 10, wherein the first and second web infeed assemblies, and the first and second slitting assemblies, are arranged in line with the lumbar elastic infeed. 12. The apparatus according to any one of paragraphs 1 to 10, wherein the first and second web infeed assemblies and the first and second slitting assemblies are arranged nonlinearly with respect to the lumbar elastic infeed. 13. The apparatus according to any one of paragraphs 1 to 12, further comprising: a feed web infeed assembly arranged to feed a single continuous feeder web in the feed direction; and a third slitting assembly arranged to slit the feeder web along a fourth cutting line extending in the feed direction to form first and second continuous webs. 14. The apparatus according to any one of paragraphs 1 to 12, wherein the first and second web infeed assemblies are provided in the form of a single supply web infeed assembly that supplies the first and second continuous webs in the supply direction in the form of a single supply web slit by the first and second slitting assemblies along first, second and third cutting lines extending in the supply direction to form the first and second backsheet strips and the first, second and third topsheet strips. 15. A method for manufacturing a torso surround for use in the manufacture of a pull-up diaper product, Operating first and second web infeed assemblies (51, 53) to supply a first continuous web and a second continuous web in a predetermined supply direction, wherein the first continuous web forms a broad first backsheet strip defining a continuous, aligned waist and leg section extending in the supply direction, and a narrow second backsheet strip defining a continuous waist section extending in the supply direction, and the second continuous web forms narrow first and second topsheet strips and a broad third topsheet strip. To separate the first and second backsheet strips, the first slitting assembly (60) is operated to slit the first continuous web along a first cutting line extending in the supply direction, To separate the first, second, and third top sheet strips, the second slitting assembly (66) is operated to slit the second continuous web along the second and third cutting lines extending in the supply direction, To operate the lumbar elastic infeed (68) to supply lumbar elastic strands under tension between the lumbar section of the first backsheet strip and the first topsheet strip, and between the lumbar section of the second backsheet strip and the second topsheet strip, To operate at least one welding assembly (74) to intermittently weld the lumbar section of the first backsheet to the first top strip in the feed direction in order to capture a lumbar elastic strand between the lumbar section of the first backsheet strip and the first top strip, and to intermittently weld the lumbar section of the second backsheet strip to the second top strip in the feed direction in order to capture a lumbar elastic strand between the lumbar section of the second backsheet strip and the second top strip, The adhesive is applied to the leg elastic strand using an adhesive applicator (76), The leg elastic infeed (78) is operated to apply the leg elastic strands nonlinearly with respect to the supply direction under tension between the leg section of the first backsheet strip and the third topsheet strip, A method that includes the following steps. 16. The method according to paragraph 15, wherein the step of operating the first and second slitting assemblies (60, 66) to slit the first and second continuous webs is performed upstream of at least one welding assembly (74). 17. The method according to paragraph 15, wherein the step of operating a second slitting assembly (66) to slit a second continuous web is performed upstream of at least one welding assembly (74), and the step of operating a first slitting assembly (60) to slit a first continuous web is performed downstream of at least one welding assembly (74). 18. The method according to any one of paragraphs 15 to 17, further comprising operating a leg elastic infeed to apply a leg elastic strand in a periodic wave pattern along a leg section in the supply direction. 19. The method according to any one of paragraphs 15 to 18, wherein the step of welding the waist sections of the first and second backsheet strips to the respective topsheet strip and waist elastic strands includes feeding the waist elastic strands sandwiched between the respective topsheet strip and backsheet strip between at least one blade-type ultrasonic horn having a grooved work surface and at least one opposing anvil having a smooth or grooved ridge, and intermittently welding the respective top and backsheet strips to each other in the feeding direction so as to capture the waist elastic strands between the topsheet strip and backsheet strip. 20. The method according to any one of paragraphs 15 to 18, wherein the step of welding the waist sections of the first and second backsheet strips to the respective topsheet strip and waist elastic strands includes feeding the waist elastic strands sandwiched between the respective topsheet strip and backsheet strip between at least one rotary horn or at least one blade-type ultrasonic horn having a smooth or grooved work surface and at least one opposing anvil having a grooved ridge, and intermittently welding the respective top and backsheet strips to each other in the feeding direction so as to capture the waist elastic strands between the topsheet strip and backsheet strip. 21. The method according to any one of paragraphs 15 to 20, further comprising operating a folding unit (84) to fold the respective outer edges of the first and second backsheet strips, and covering the folded edges of each backsheet strip with the respective topsheet strip. 22. The method according to any one of paragraphs 15 to 20, further comprising operating at least one folding unit (84) to fold each of the outer edges of the first and second backsheet strips to cover the outer edges of each of the topsheet strips. 23. To operate the abdominal elastic infeed (80) to insert an abdominal elastic strand under tension in the supply direction between the leg section of the first backsheet strip and the third topsheet strip, The method according to any one of paragraphs 15 to 22, further comprising securing the abdominal elastic strand to the first backsheet strip with an adhesive applicator (76). 24. The method according to any one of paragraphs 15 to 23, further comprising: moving the first and second backseat strips apart from each other in a direction transverse to the supply direction; and operating at least one spreading unit (62, 64) to position the leg section of the first backseat strip between the lumbar section of the first backseat strip and the lumbar section of the second backseat strip. 25. The method according to any one of paragraphs 15 to 24, further comprising the steps of feeding first and second continuous webs from a single roll of material arranged to deliver a single feed web in the feed direction, and operating at least one slitting unit and at least one spreading unit to slit along a fourth cutting line extending in the feed direction to form the first and second continuous webs. 26. The method according to any one of paragraphs 15 to 24, further comprising the steps of feeding first and second continuous webs from a single roll of material arranged to deliver the web in the feeding direction, and operating at least one slitting unit and at least one spreading unit to slit along first, second and third cutting lines to form first and second backsheet strips, and first, second and third topsheet strips.

Claims

1. A device for manufacturing a torso surround portion for use in the manufacture of pull-up diaper products, First and second web infeed assemblies (51, 53) for supplying a first continuous web and a second continuous web (50, 52) in a supply direction (F), wherein the first continuous web forms a broad first backsheet strip defining a continuous, aligned waist and leg section extending in the supply direction, and a narrow second backsheet strip defining a continuous waist section extending in the supply direction, and the second continuous web forms narrow first and second topsheet strips and a broad third topsheet strip, A first slitting assembly (60) is positioned to receive and slit the first continuous web along a first cutting line extending in the supply direction in order to separate the first and second backsheet strips, A second slitting assembly (66) is positioned to receive and slit the second continuous web along second and third cutting lines extending in the supply direction in order to separate the first, second, and third top sheet strips, A lumbar elastic infeed (68) is provided on the lumbar section of the first backsheet strip and on the lumbar section of the second backsheet strip to supply the lumbar elastic strand under tension in the supply direction, First and second lumbar supply assemblies (70, 72) are positioned to orient the first and second top sheet strips in order to sandwich the lumbar elastic strand between the lumbar section of the first backsheet strip and the first top sheet strip, and between the lumbar section of the second backsheet strip and the second top sheet strip, A welding assembly (74) intermittently welds the lumbar elastic strand of the first backsheet to the first top strip in the supply direction in order to capture the lumbar elastic strand between the lumbar section of the first backsheet and the first top strip, and intermittently welds the second backsheet strip to the second top strip in the supply direction in order to capture the lumbar elastic strand between the second backsheet strip and the second top strip, An adhesive unit (76) is positioned to apply leg adhesive to the leg section of the first backsheet strip, A leg elastic infeed (78) is provided, which is arranged so as to insert the leg elastic strands onto the leg adhesive in a non-linear pattern and under tension, generally in the supply direction. A leg supply assembly (82) is provided, which covers the first backsheet strip and is positioned to orient the third topsheet strip so as to sandwich the leg elastic strand between the first backsheet strip and the third topsheet strip, A device equipped with the following features.

2. The apparatus according to claim 1, wherein both the first and second slitting assemblies (60, 66) are located upstream of the lumbar elastic infeed (68), or the second slitting assembly is located upstream of the lumbar elastic infeed (68) and the first slitting assembly (60) is located downstream of the at least one welding assembly (74).

3. The apparatus according to claim 1 or 2, wherein the leg elastic infeed includes one or more reciprocating leg elastic infeed elements for inserting the leg elastic strand so as to extend in a periodic wave pattern along the leg section in the supply direction.

4. The apparatus according to any one of claims 1 to 3, further comprising one or more lumbar edge folding units (84) positioned downstream of the lumbar elastic infeed assembly, positioned upstream of the second lumbar feed assembly to fold the outer edges of each of the first and second backsheet strips, thereby covering the folded edges of each backsheet strip before each of the topsheet strips moves through the welding assembly in the feed direction, or positioned downstream of the second lumbar feed assembly to fold the outer edges of each of the first and second backsheet strips, thereby covering the folded edges of each backsheet strip, the apparatus according to any one of claims 1 to 3.

5. The apparatus according to any one of claims 1 to 4, further comprising a ventral elastic infeed (80) positioned upstream of the leg supply assembly in the supply direction and arranged to insert a ventral elastic strand extending under tension in the supply direction onto the adhesive of the leg section of the first backsheet strip, wherein the leg supply assembly directs the third top sheet strip to cover the leg section of the first backsheet strip, sandwiching the leg-side elastic strand and the ventral elastic strand between the third top sheet strip and the leg section of the first backsheet strip.

6. The apparatus according to any one of claims 1 to 5, further comprising one or more web spreaders (62, 64) for arranging the first and second backsheet strips adjacent to but separated from each other in a direction transverse to the supply direction, and for positioning the leg section of the first backsheet strip between the waist sections.

7. The aforementioned welded assembly, At least one blade-type ultrasonic horn having a grooved work surface, and at least one opposing anvil having a smooth or grooved ridge, wherein the horn and anvil are positioned on either side of the supply path through the welding assembly, thereby the waist elastic strand is sandwiched between the waist section of the first backsheet and the first topsheet, and between the waist section of the second backsheet and the second topsheet, moving between the horn and anvil in the supply direction, or At least one rotary or bladed ultrasonic horn having a smooth or grooved working surface, and at least one opposing anvil having a grooved ridge, wherein the horn and anvil are positioned on either side of the supply path through the welding assembly, thereby the waist elastic strand is sandwiched between the waist section of the first backsheet and the first topsheet, and between the waist section of the second backsheet and the second topsheet, and moves between the horn and anvil in the supply direction. The apparatus according to any one of claims 1 to 6, comprising:

8. The apparatus according to any one of claims 1 to 7, wherein the first and second web infeed assemblies and the first and second slitting assemblies are arranged linearly or nonlinearly with respect to the lumbar elastic infeed.

9. The system further includes a feed web infeed assembly arranged to feed a single continuous feeder web in the feed direction, and a third slitting assembly arranged to slit the feeder web along a fourth cutting line extending in the feed direction to form the first and second continuous webs, or The apparatus according to any one of claims 1 to 8, wherein the first and second web infeed assemblies are provided in the form of a single supply web infeed assembly that supplies the first and second continuous webs in the supply direction in the form of a single supply web slit by the first and second slitting assemblies along the first, second and third cutting lines extending in the supply direction to form the first and second backsheet strips and the first, second and third topsheet strips.

10. A method for manufacturing a torso surround for use in the manufacture of a pant-type diaper product, Steps of operating first and second web infeed assemblies (51, 53) to supply a first continuous web and a second continuous web in a predetermined supply direction, wherein the first continuous web forms a broad first backsheet strip defining a continuous row of waist and leg sections extending in the supply direction, and a narrow second backsheet strip defining a continuous waist section extending in the supply direction, and the second continuous web forms narrow first and second topsheet strips and a broad third topsheet strip, The steps include operating a first slitting assembly (60) to slit the first continuous web along a first cutting line extending in the supply direction in order to separate the first and second backsheet strips, The steps include operating a second slitting assembly (66) to slit the second continuous web along second and third cutting lines extending in the supply direction in order to separate the first, second, and third top sheet strips, The steps include operating a lumbar elastic infeed (68) to supply lumbar elastic strands under tension between the lumbar section of the first backsheet strip and the first topsheet strip, and between the lumbar section of the second backsheet strip and the second topsheet strip, The steps include operating at least one welding assembly (74) to intermittently weld the lumbar section of the first backsheet to the first top strip in the supply direction in order to capture the lumbar elastic strand between the lumbar section of the first backsheet and the first top strip, and to intermittently weld the lumbar section of the second backsheet strip to the second top strip in the supply direction in order to capture the lumbar elastic strand between the lumbar section of the second backsheet strip and the second top strip, The steps include applying adhesive to the leg elastic strand using an adhesive applicator (76), The steps include: operating a leg elastic infeed (78) to apply the leg elastic strands nonlinearly with respect to the supply direction under tension between the leg section of the first backsheet strip and the third topsheet strip; Methods that include...

11. The method according to claim 10, wherein the step of operating the first and second slitting assemblies (60, 66) to slit the first and second continuous webs is performed upstream of the at least one welding assembly (74), or the step of operating the second slitting assembly (66) to slit the second continuous web is performed upstream of the at least one welding assembly (74), and the step of operating the first slitting assembly (60) to slit the first continuous web is performed downstream of the at least one welding assembly (74).

12. The method according to claim 10 or 11, further comprising the step of operating the leg elastic infeed to apply the leg elastic strand along the leg section in a periodic wave pattern in the supply direction.

13. The step of welding the waist sections of the first and second backsheet strips to the respective topsheet strip and waist elastic strands comprises (A) supplying the waist elastic strands sandwiched between the respective topsheet strip and backsheet strip between at least one blade-type ultrasonic horn having a grooved working surface and at least one opposing anvil having a smooth or grooved ridge, and intermittently moving the respective top and backsheet strips in the supply direction so as to capture the waist elastic strands between the topsheet strip and the backsheet strip. The method according to any one of claims 10 to 12, comprising the steps of (B) welding each of the top sheet strips and back sheet strips together, or (B) supplying the lumbar elastic strand sandwiched between each of the top sheet strips and back sheet strips between at least one rotary horn or at least one blade-type ultrasonic horn having a smooth or grooved working surface and at least one opposing anvil having a grooved ridge, and intermittently welding each of the top and back sheet strips together in the supply direction so as to capture the lumbar elastic strand between the top sheet strip and the back sheet strip.

14. The method according to any one of claims 10 to 13, further comprising the steps of: operating at least one folding unit (84) to fold the respective outer edges of the first and second backsheet strips and covering the folded edges of each backsheet strip with the respective topsheet strip; or operating at least one folding unit (84) to fold the respective outer edges of the first and second backsheet strips to cover the respective topsheet strips.

15. The steps include: operating the abdominal elastic infeed (80) to insert an abdominal elastic strand under tension in the supply direction between the leg section of the first backsheet strip and the third topsheet strip; The method according to any one of claims 10 to 14, further comprising the step of fixing the abdominal elastic strand to the first backsheet strip with an adhesive applicator (76).

16. The method according to any one of claims 10 to 15, further comprising the step of moving at least one spreading unit (62, 64) to separate the first and second backseat strips from each other in a direction transverse to the supply direction, and positioning the leg section of the first backseat strip between the waist section of the first backseat strip and the waist section of the second backseat strip.

17. The method according to any one of claims 10 to 16, further comprising the steps of: feeding the first and second continuous webs from a single roll of material arranged to deliver a single feed web in the feed direction; and operating the at least one slitting unit and the at least one spreading unit to slit along a fourth cutting line extending in the feed direction to form the first and second continuous webs, or to slit along the first, second and third cutting lines to form the first and second backsheet strips and the first, second and third topsheet strips.

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