Methods and apparatus for forming disposable products at high speeds with small machine footprint

Abstract

The present invention provides machinery used to create products (for instance disposable products). The machinery is operated at high speed, with the machine occupying a small footprint. Materials can be fed into the manufacturing process vertically (from above or below), using assembly stations to feed completed components into the system at appropriate stations. Additionally, restocking of raw components can be accomplished by robotic means of transferring the raw material from staging areas into infeeding or splicing stations, without the need for human operators.

Claims

1. A multi-level machine for manufacturing disposable products, the machine comprising: a first floor surface carrying machinery for manufacturing a disposable product; a second floor surface vertically spaced apart from said first floor surface, said second floor surface carrying a plurality of auto-fed material unwinding systems; said auto-fed material unwinding systems comprising a plurality of turret systems, said turret systems carrying an expiring roll of material and a standby roll of material positioned at a standby location and selectively coupled to said expiring roll of material; said auto-fed material unwinding systems feeding materials from said expiring roll of material vertically through openings in the second floor to said machinery for manufacturing a disposable product on the first floor surface a plurality of waiting new material rolls staged at material addresses corresponding to at least one of said turret systems; a demand and replacement system initiating a material replacement sequence of acquiring and transporting one of said waiting new material rolls from one of said material addresses to said standby location.

2. A multi-level machine for manufacturing disposable products, the machine comprising: a first floor surface carrying machinery for manufacturing a disposable product comprising a plurality of infeeds of material components; a second floor surface vertically spaced apart from said first floor surface, said second floor surface carrying a plurality of material supply rolls carried by a plurality of turret systems; said plurality of material supply rolls positioned vertically proximally to said plurality of infeeds of material components; said plurality of turret systems feeding said plurality of material supply rolls to said machinery for manufacturing a disposable product on the first floor surface vertically through openings in the second floor surface.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIGS. 1A and 1B are a schematic of a representative web processing system;

(2) FIG. 2 is a top view of a floorplan layout of the web processing system of the present invention;

(3) FIG. 3 is a top view of a floorplan layout of the web processing system of the present invention;

(4) FIG. 4 is a side view of the ground level and mezzanine levels of the web processing system of the present invention;

(5) FIG. 5 is a side view of an extension panel construction section of the present invention;

(6) FIG. 6 is a side view of a back ear final construction section of the present invention;

(7) FIG. 7 is a side view of a soft backsheet lamination section of the present invention.

(8) FIG. 8 is a perspective view of a mezzanine and floor level of a web processing system of the present invention used to create a pant-type product;

(9) FIG. 9 is a perspective view of an alternate mezzanine and floor level of a web processing system of the present invention used to create a brief-type product;

(10) FIG. 10 is a perspective view of a loaded material roll supply cart of the present invention;

(11) FIG. 11 is a perspective view of a gantry crane system carrying a material roll used in the present invention, shown in a retracted position;

(12) FIG. 12 is a perspective view of a gantry crane system carrying a material roll used in the present invention, shown in an extended position;

(13) FIG. 13 is a side view of a turret unwind and splicing system for carrying expiring material rolls and waiting new material rolls.

DESCRIPTION OF THE PREFERRED EMBODIMENT

(14) Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structures. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.

(15) It is noted that the present waste minimization techniques and apparatus are described herein with respect to products such as diapers, but as previously mentioned, can be applied to a wide variety of processes in which discrete components are applied sequentially.

(16) Referring to FIGS. 1A and 1B, a two-level disposable product manufacturing process is disclosed. Portions of the disposable product are formed on a floor level, and other portions are formed on an upper or mezzanine level.

(17) On the floor level, the web processing operation starts with incorporating raw materials such as paper pulp and super absorbent polymer (SAP) in a pulp mill. The mixture is sent to a core forming drum, where cores are formed for retaining liquids. A core can be placed on a tissue and processed as shown. Eventually, an additional tissue layer can be applied to sandwich the core. In the illustrated embodiment, two independent cores can be formed and joined together at a compression unit.

(18) Simultaneously formed on the upper level are back ear and front ear portions of the disposable product, which can be formed with methods and apparatus such as those disclosed in the simultaneously pending U.S. patent application Ser. No. 12/925,033, incorporated herein by reference, and described in the schematic as the NOSE unit.

(19) As disclosed therein, discrete preferably trapezoidal ear pieces are initially cut alternating between a correct orientation and an incorrect (reversed) orientation. The reversed car is required to be rotated 180 into the correct orientation such that the ears and associated tape present a left ear and a right ear on the diaper.

(20) To accomplish the reversal of the ear pattern, discrete ear pieces are picked up at the nested ear pitch by an ear turner assembly that will expand to a pitch large enough for ears to be unnested and allow clearance for every other ear to be rotated. The rotated ears are then unnested and into the correct orientation.

(21) Two ear turner assemblies can be provided, to rotate every other ear applied to the right side of the product, and every other ear applied to the left side of the product. In this manner, for a single product, one of the two ears will have been rotated 180.

(22) Ear application to a chassis web can be by a bump method with intermittent adhesive applied to the chassis web, or can be by vacuum transfer.

(23) Still on the upper level, a cuff portion of the diaper can be supplied from the upper level, the top sheet can be stored and unwound, an acquisition layer can be stored and unwound, and a non woven backsheet/poly laminate can be stored, formed and unwound. All of the stored materials on the upper level can be retrieved automatically and mechanically to restock as the rolls are used up. Eventually the upper level materials, which generally overly the floor level machinery, are supplied down to the floor level for use in the diaper manufacturing process.

(24) Together on the floor level, the back ear, front ear, cuff (now including cuff elastic), top sheet, acquisition layer, and backsheet poly laminate are preferably simultaneously placed and coupled together and coupled with the previously formed core. The web can undergo folding, extraction and trimming of excess material, and application of material to tighten the diaper about the waist. Eventually, the product is folded and packaged.

(25) Referring now to FIGS. 2 and 4, a preferred floor plan of the present invention is shown both from a top view (FIG. 2) and a side view (FIG. 4). As indicated, pulp rolls 200 feed raw pulp into a pulp mill 204, where the pulp is de-bonded. Super absorbent polymer is added from station 12. The SAP/pulp mixture, or pulp/SAP blend, or pulp and SAP is fed onto core forming drum 14. The pulp/SAP mixture is introduced to a core forming apparatus. Cores are made by conveying the pulp/SAP mixture through a duct and into a vacuum forming drum. Cores from core forming drum 14 are conveyed by conveyor 18 and core accelerator 20 downline. A secondary core forming drum 16 is likewise employed if a secondary core is desired, and the secondary core is passed through the debulking unit 22, and onto the core accelerator 20 and placed atop the primary core. A compression conveyor 23 keeps control of the core to pass it through to the introduction of poly laminate backsheet. A backsheet laminate is comprised preferably of a continuous nonwoven layer (for soft, cloth like feel), along with a moisture barrier layer, generally made from polypropylene or polyethylene film. This layer can be glued, ultrasonically bonded over the length of the backsheet, or applied as a patch with glue using a slip/cut process.

(26) Referring to FIG. 7, the formation of the soft backsheet lamination is shown in side view. A nonwoven backsheet roll is carried on the upper level along with its backup roll to be spliced in as inventories deplete (see FIG. 3) and laminated together at station 110.

(27) Referring to FIGS. 4 and 7, it can be seen that a process interface module 110 is carried between said unwind level and said main processing level, said main level containing splice preparation equipment 110 located between the unwind level and the main process system level, for instance by hanging a process interface module 110 from a supplied I-beam. The process interface module can achieve many functions, such as slitting, laminating, and splice preparation. After being transported vertically, the poly laminated backsheet is introduced to the fed from the bottom, at station 25 (see FIGS. 3, 7). A nonwoven topsheet assembly, including a lycra and cuff portion and an absorbent distribution layer, enters the system prior to the boundary compression unit. Still referring to FIG. 3, it is noted that actual raw materials and the locations of those materials could vary in floor plan, but it is preferred that the materials remain on the vertical levels shown.

(28) Referring back to FIG. 4, this poly laminate and core combination is passed to boundary compression unit 29. It is at unit 29 that other diaper elements are introduced in pre-formed fashion, from the upper level components on FIG. 1B. Also, lycra unwind unit 27 introduces lycra, in addition to the pre-formed upper level diaper components, at this point.

(29) Referring to FIG. 2, the upper level components comprise the front ear non-woven supply unit 24, to supply the front ears, the acquisition layer provided from unwind unit 26, the top sheet supplied from the supply and unwind station 28, and the cuff components supplied from the cuff supply unit 30 to supply the cuff material for lower level slitting/spreading and introduction of lycra, and foldover of the lycra to form the cuff. These materials are fed in the pathways shown, and introduced to the boundary compression unit 29, in the sequence shown in FIGS. 1A and 1B.

(30) Still referring to FIG. 2, on the upper level, the back ear and extension panel are formed at station 60. The back ear section is formed as shown in FIG. 6, using the methods and apparatus formed in U.S. application Ser. No. 12/925,033, disclosed herein by reference. The extension panel section is formed as shown in FIG. 5. In particular, the depiction and description shown in FIG. 19A-26 of U.S. application Ser. No. 12/925,033 results in the back ear/extension panel formation depicted in FIGS. 5 and 6. Ultimately the back ear/extension panel construction is transported as depicted, downwards toward the nested zero waste ear rotation unit 27 as shown on FIG. 4, also described in detail in U.S. application Ser. No. 12/925,033, for instance at FIG. 8A.

(31) Still referring to FIG. 4, front ears are formed at unit 24 using preferably non-woven material, and are placed onto the chassis web preferably by slip-cut technique after being conveyed circuitously and downwardly towards the boundary compression unit 29.

(32) Cuff unit 30 convoys, from the upper level, cuff material to the lower level where right and left cuffs are formed by passing the cuff material first through slitter 42, spreader 44. Lycra unwind unit 27 feeds strands of lycra onto the cuff material, and then a bonding/foldover unit 46 seals the lycra strands within a foldover portion of the non-woven material to create the cuff.

(33) An additional bonding unit 48 couples the previously created cuff with the incoming topsheet material 28, fed from the upper level downwardly. The cuff/topsheet combination is fed toward incoming acquisition layer 26 for acquisition placement at station 50 and that combination is then fed toward the NOSE unit 32, where the previously formed materials will be joined with the cuff/topsheet/acquisition combination. After the NOSE limit, all of the materials are then joined at the boundary compression unit, including the nonwoven topsheet assembly, including a absorbent distribution layer, lycra and cuff portion, which have entered the system, prior to the boundary compression unit.

(34) Now moving right to left on FIG. 4, the formed diaper can be subjected to folding plows 52 to fold over front ear and back ear/extension panels, passed through a die cut unit 56 to sever individual products from the previously continuous web, and then past tucker blades 54 to fold the products at the crotch region or elsewhere desired for packaging and bagging operations at station 00.

(35) Referring now to FIG. 5, the extension panel construction is shown. The formation of side panel assemblies begins with an non-woven web material 318, supplied in primary and backup roll fashion, with splicer 320 and accumulator 322 used to provide a continuous web, which is slit and spread into discrete non-woven web portions (see FIG. 2), each of the non-woven web portions also preferably being cut in the cross-machine direction into the preferred size.

(36) To each of the discrete non-woven web portions, one or more fastening mechanisms are applied. Fastening mechanisms can be tape tabs, covered tape tabs, strips of hook and loop material, continuous hook and loop material, patches of hook and loop material, etc. The fastening mechanisms will be unfastened and refastened about the waist of the user to tighten the disposable garment about the waist.

(37) The fastening mechanisms are supplied by incoming web 62, slit and spread by units 64 and applied via slip cut unit 324 onto the non-woven 318.

(38) Neat, the non-woven webs 318 carrying fastening mechanisms 322 are folded over, creating a folded web 318 and folded-over fastening mechanisms. This causes the combination of the non-woven web 318 and the fastening mechanisms to be narrower than the discrete non-woven web portions. It is noted that the folded fastening mechanisms of web portions 318a and 318b will have opposing fastening mechanisms 322 as they will become the right and left hip waist fastening mechanisms, respectively, once placed about the waist of a user (shown later in the process).

(39) Referring now to FIG. 6, the back ear final construction is shown, a cross sectional view of the designated view of FIG. 2. This process is disclosed, e.g., in FIGS. 20-22 of simultaneously pending U.S. patent application Ser. No. 12/925,033, incorporated herein by reference.

(40) The back ear final construction receives where indicated the partially completed extension panel assembly where indicated, which first pass through additional folding units 342. A back ear web 28 is provided upon which to attach the previously formed extension panel. This too can be slit and spread into discrete stretch laminate web portions.

(41) Next, the non-woven web portions, including their respective fastening mechanisms, are slip/cut and bonded to stretch laminate web portions in a staggered relationship, forming the side panel assemblies in four different lanes. The non-woven web portions can be bonded to the stretch laminate web portions in any fashion, such as by ultrasonic bonding.

(42) The stretch laminate portions can also be folded if desired, or the stretch laminate portions in combination with the non-woven web portions can all be folded together and again, by plows 52. The back ear/extension panel construction assembly is then conveyed to the floor level NOSE unit 32, ultimately for placement with the other components and the boundary compression unit 29.

(43) Referring now to FIG. 8, a perspective view of a mezzanine ((or material unwinding) level 480 and floor (or main processing) level 482 of a web processing system used to create a pant-type product of the present invention is shown. The material unwinding level 480 is a human-free zone, intended for no human occupation during machine operation in areas accessible by a gantry crane 500.

(44) On the floor level, a series of ground floor material access doors 464 are provided. These access doors 464 are each preferably dedicated to a single material. For example in a preferred embodiment, door address 416 is for transporting inner non-woven material from the ground level to the mezzanine level. Address 414 is for outer non-woven, address 412 for non-woven backsheet material, address 410 for non-woven topsheet material, address 408 for poly backsheet material, address 406 for acquisition layer material, and address 404 for tissue material. A vertical reciprocating conveyor (VRC) operates behind each access door 464 to lift a full rack of waiting new material rolls (FIG. 10) supplied into the addresses in magazines to the mezzanine level. Alternatively, descending robots can be used in place of the VRCs.

(45) Preferably, when an access door 464 is open, a corresponding access door on the mezzanine level is closed, and vice versa.

(46) On the material unwinding level 480, unmanned, auto-fed material unwinding systems are provided corresponding to the materials supplied to addresses above. In a preferred layout, turret unwind 424 is for a tissue unwind, corresponding to address 404 on the ground and mezzanine levels (turret unwind detail provided in FIG. 13). An acquisition layer unwind station 426 (corresponding to station 406) is provided, as are turret unwinds for poly backsheet unwind 428 (corresponding to station 408), non-woven topsheet layer 430 (corresponding to station 410), non-woven backsheet layer 422 (corresponding to station 412), outer chassis non-woven unwind 434 (corresponding to station 414), and inner chassis nonwoven unwind 436 (corresponding to station 416).

(47) As material is unwound from the unwinds 424, 426, 428, 430, 432, 434, and 436, material is fed through material supply slots 462 in the floor of the mezzanine level, downward to the ground level 482. There, the materials are fed into and used by the system, as shown in FIGS. 1A and 1B, 2, and 4-7.

(48) As a connected material roll feeds material from the mezzanine level through an opening 462 in the floor of the mezzanine level to the floor level, the material roll will eventually expire. Referring now to FIG. 13, a side view of a turret unwind and splicing system for carrying expiring material rolls and waiting news material rolls is shown.

(49) Turret unwinds are described for exemplary purposes in U.S. Pat. Nos. 6,701,992, 3,655,143, 3,306,546, 3,460,775, which are incorporated herein by reference.

(50) Still referring to FIG. 13, when the system detects that one of the expiring material rolls 602 in the top position on unwinds 424, 426, 428, 430, 432, 434, and 436 is set to expire, a splice sequence is initiated between the expiring material roll 602 and the waiting new material roll 602. In a preferable embodiment, a running or expiring roll 602 is at a top position of the turret unwind of FIG. 13, with a waiting new material roll 602 placed by the gantry crane system located at a bottom position of the turret unwind on shaft 616. When it is detected that the running roll is coming close to expiration, the waiting new material roll 602 is driven up to a surface speed of expiring roll. A hot wire splicer arm 624 moves in adjacent to the walling new material roll, brings in the running web into close proximity to the waiting new material roll 602. At the moment of splice, the hot wire arm 624 bumps the expiring web 602 to the waiting new material roll, and at the precise moment of contact, a splice tape is introduced to splice the waiting new material roll 602 and the expiring roll 602 together, and at the same time as the bump, the hot wire arm 624 severs the running web with a hot wire. In this manner, the expiring web is instantly taped to the leading edge of the new roll.

(51) Next, the rotating turret arm 622 rotates clockwise to place the waiting new material roll 602 into the expiring roll position 602. A kicker ring 620 next bumps the remainder of the previously expiring roll 602 off of shaft 616 for discard.

(52) Next, the system demands a replacement waiting new material roll to place upon the shaft 616 at the bottom position of the turret unwind.

(53) At the mezzanine level addresses 404, 406, 408, 410, 412, 414, and 416, magazines of waiting new material roll (FIG. 10) are received from the ground level, and wait for demand. The gantry crane 500 is summoned to pick up a material roll from a cart (FIG. 10) stationed at the dedicated VRC stations, and transport the full material roll to a turret unwind system dedicated to that particular material. The system detects which waiting new material roll requires replacement after its predecessor has been spliced and turned into an expiring roll, and then travels the crane/robot combination 500/502 to the appropriate mezzanine level address 404, 406, 408, 410, 412, 414, and 416 and obtains a replacement wailing new material roll.

(54) The gantry robot is programmed to discard the remainder of the expiring roll into a waste chute (not shown) on the mezzanine level, and then to obtain a replacement waiting new material roll from the dedicated VRC from which the appropriate material is located on the cart. When the system detects that all rolls of waiting new material roll are used from a supply cart (FIG. 10), the VRC containing the empty cart is automatically transported to the floor level for replacement of all of the waiting new material rolls.

(55) During machine operation, those portions of the mezzanine level accessible by a gantry crane system 500 are designed to operate without human occupation. This not only provides an added measure of safety, but an added measure of automation for the machine. A gantry crane system 500 operates robotically on an overhead system that allows movement across a horizontal plane. The present invention uses the gantry crane 500 for horizontal movement, and a robotic arm 502 capable of vertical movement and rotation, and equipped with a camera operated location system (see FIGS. 11 and 12) to detect the position of the core of waiting new material rolls for pickup, and to deposit precisely a core of a replacement waiting new material roll onto arms of turret unwinds for use in the system.

(56) Gantry robots 500 are preferred for this pick and place applications because of positioning accuracy, aided by vision systems. Positional programming is done in reference to an X, Y, Z coordinate system.

(57) Although humans can access the mezzanine level 480 by stairs 460 for equipment service, no human occupation during operation is intended. Humans can also access the mezzanine level 480 behind access door 452, this portion of the mezzanine level 480 is physically separated from the human-free zone of the other portions of the mezzanine level 480. Access door 452 is used to access physically divided power station and control station 450. This station is for control panels, ultrasonic bonder control, and drive controls.

(58) Also evident on FIG. 8 are pulp rolls 402 supplying pump mill 400 at the beginning of the processing on the main floor, and a final knife unit 466, an car folding and horizontal pad turner 468, and lastly a cross-folder 470 which discharges the diapers to product packaging downstream.

(59) This unique machine layout has achieved significant machine length decrease. Exemplary prior art diaper making machines for a pant process are approximately 44 meters, and his new machine layout can be achieved in less than 34 meters, a 23% shorter overall machine length from the beginning of the pulp unwind to the end of cross-folder 470. A range of 20-35% decrease in machine length can be achieved.

(60) Referring now to FIG. 9, a perspective view of an alternate mezzanine and floor level of a web processing system of the present invention used to create a brief-type product is shown.

(61) In this embodiment, carts of materials are staged initially on the ground floor. In an exemplary embodiment, loading carts are position at stations 510 (upper tissue), 512 (lower tissue), 514 (poly backsheet), 516 (non-woven backsheet), 518 (back ear), 520 (acquisition layer), 521 (front ear), 522 (non-woven topsheet), 524 (extension panel), and 526 (cuff). These materials are transported to and placed behind VRC door 464 and transported by VRC 550 to the mezzanine level 480. A similar demand/replacement system is employed in the brief-type product floor layout as in the pant-type product layout described in FIG. 8. Namely, expiring materials are fed through slots in the floor of the mezzanine level, a splicing sequence is initiated, and a material replacement sequence is initiated, whereby a material roll is acquired by crane/robot combination 500/502 and transported to and placed on the turret unwind systems.

(62) In the pictured embodiment, a lower tissue turret unwind 532 is provided as are turret unwind stations for upper tissue (530), poly backsheet (534), non-woven backsheet (536), back ear (538), acquisition layer (540), front ear (541), inner top-sheet non-woven extension panel (544), cuff (546). These materials are all fed downward to be used in a brief-type diaper.

(63) This unique machine layout has achieved significant machine length decrease. Exemplary prior art diaper making machines for a brief process are approximately 41 meters, and this new machine layout can be achieved in less than 29 meters, a 30% shorter overall machine length from the beginning of the pulp unwind to the end of cross-folder 470. A range of 20-35% decrease in machine length can be achieved. A power station and control station 592 is provided. Additionally, certain components can be fed at the ground level, for instance an offline stretch material unwind 590.

(64) Referring now to FIG. 10, a perspective view of a loaded material roll supply cart 600 or magazine of the present invention is shown. A material staging magazine 600 is provided to carry waiting new material rolls 602 from a ground level to a mezzanine level 480, the mezzanine level 480 carrying a series of turret unwind systems for dispensing materials from the mezzanine level back to the ground level. The material staging magazines 600 contain a series of individual roll stabilization features 604 which prevent waiting new material rolls 604 from tipping during material transport and unloading. The cart 600 is filled on the ground level, and rolled into the appropriate ground level addresses 404, 406, 408, 410, 412, 414, and 416, for transport to mezzanine level addresses 404, 406, 408, 410, 412, 414, and 416. The rolls are then summoned as described above.

(65) Referring now to FIG. 11, a perspective view of a roll transfer device 700 comprising a gantry crane 500 system carrying a material roll 602 used in the present invention is shown in a retracted position. A camera 612 is used to detect the position of a core of a waiting new material roll during pickup of a waiting new material roll by the robot off of a cart 600, and also to detect the position of the shaft 616 on the turret unwind systems (FIG. 13) upon which to push the material roll 602 with roll bumper 610. Lasers, radar, or ultrasonics can also be used to measure distance and position, either in addition to or instead of camera 612.

(66) FIG. 12 is a perspective view of a gantry crane 500 carrying a material roll 602 used in the present invention, the robotic arm 502 shown in an extended position.

(67) The foregoing is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.