Abstract:
Dual folding apparatus using multi-width parent rolls to produce color sequenced stacks of napkins, including means for unwinding, slitting and advancing same-color product webs to a turning and lane separating device to selectively transfer first-color webs to one of two ‘folding’ lanes and selectively transfer second-color webs to the other lane. First and second-color webs in superposed side by side advancement are embossed, and webs of the same color are directed to one side of a dual folder for longitudinal folding, cutoff, and transverse folding while the second-color web is processed in the other side of the dual folder. Napkins of one color are superposed on napkins of a second color and delivered as a pair between delivery belts for packout into stacks having napkins of alternating color. Two adjacent delivery lanes deliver stacks of the same mixed colors. In machines with four delivery lanes, first and second lanes can have alternating first and second colors, while the the third and fourth lanes can have alternating third and fourth color stacks. Other embodiments include different placement of unwind stands, arrangement of parent roll colors, and other turning and lane changing means.

Description:
BACKGROUND AND SUMMARY OF THE INVENTION  
         [0001]    This invention relates to folding apparatus, and more particularly, napkin folders to make product stacks having a two color sequence in each stack.  
           [0002]    The invention is useful as applied to ‘dual folders, a well known face-to face arrangement of two single folders to double production of 1-ply semi-crepe napkins for consumer and commercial use.  
           [0003]    Introduced in the 1940&#39;s as a two wide machine with two delivery lanes, they were subsequently widened to three and four delivery lanes as paper machine widths increased.  
           [0004]    Use of recycled fiber and wider webs dictated that most current folders are four wide for lowest cost production, but all prior art folders using two wide parent rolls deliver only one color stacks since the two wide parent roll webs are processed full width and slit just before they are longitudinally folded.  
           [0005]    In current folders similar to the apparatus described in U.S. Patent of Small U.S. Pat. No. 4,349,185, parallel webs of the same color are advanced to adjacent folding plates as two separate but identical webs of the same color for transverse folding in each side of a dual follder before they are brought back together for delivery between belts as a supeposed pair of similarly colored napkins.  
           [0006]    In the instant invention, parent rolls webs are slit into two product width webs before advancing to a turning and lane changing device where different colored webs are advanced to each pair of four coacting folding plates and transversly folded for delivery in four lanes.  
           [0007]    The apparatus of this invention can produce two delivery lanes of alternatiely colored napkins from a two wide machine, a two color mixed stack and a single color stack from a three wide machine, or alternating colors in two or four lanes of a four wide machine An objective of the invention is to achieve color mixing in stacks for a choice of unwind roll locations for the most efficient material handling of new supply rolls and delivered stacks.  
           [0008]    Another object is to achieve color mixing utilizing current folder apparatus having only one knife-anvil roll pair cooperating with each single folder of the dual arrangement.  
           [0009]    A further object is to describe apparatus to compensate for transverse web growth in each of two adjacent product webs being embossed with provision to deliver folded webs with equal panels from the longitudinal folding plates.  
           [0010]    Other advantages and objects of the invention may be seen in the ensuing specification. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]    [0011]FIG. 1 is a plan view schematic illustrating a pair of supply rolls arranged on one side of two parallel folding plate lanes, a turning device, and downstream folding plates for a dual folder (not shown).  
         [0012]    [0012]FIG. 2 is a plan view schematic illustrating a pair of rolls, one on each side of the two folding lanes with associated components.  
         [0013]    [0013]FIG. 3 is a plan view schematic for two pairs of supply rolls arranged on one side of the folding lanes, with two tiers of turning devices arranged for serial processing of each pair of rolls and advancing 8 webs to a four wide folding apparatus.  
         [0014]    [0014]FIG. 4 is a side elevation schematic viewed from sightline  4 - 4  of FIG. 3  
         [0015]    [0015]FIG. 5 is a plan view schematic similar to FIG. 1 illustrating web draw rolls, spreader roll before embossing, embosser and folding plates for a dual folder.  
         [0016]    [0016]FIG. 6 is a side elevation schematic viewed from  6 - 6  of FIG. 5.  
         [0017]    [0017]FIG. 7 is a side elevation schematic illustrating two supply rolls with slitting means to produce four product webs with exiting web positions from the turning device.  
         [0018]    [0018]FIG. 8 is an end view of two single folders arranged face to face as a dual folder.  
         [0019]    [0019]FIG. 9 is an enlarged plan view schematic of the web turning device illustrating incoming and exiting webs, turning device framework and extension of bars beyond the outside margins of juxtaposed webs  
         [0020]    [0020]FIG. 10 is a side elevation from sightline  10 - 10  of FIG. 9 illustrating incoming web positions over separate turning bars and draw rolls for the pluraliuty of exiting webs.  
         [0021]    [0021]FIG. 11A is a plan view of the turning device in FIGS. 1 and 9 illustrating placement of two colored webs from the same supply roll in the same folding lane.  
         [0022]    [0022]FIG. 11B is a plan view like FIG. 11A illustrating turning bar arrangement for placement of alternately colored webs in the same lane for color mixing of different colors from adjacent folding plates.  
         [0023]    [0023]FIG. 11C is a similar plan view illustrating a bar arrangement to place similarly colored webs in the same folding lane path opposite from FIG. 11A.  
         [0024]    [0024]FIG. 12A is a similar plan view for two supply rolls located on the same side of folding lanes illustrating, like FIG. 11A, two webs from the same supply roll placed in the same folding lane path.  
         [0025]    [0025]FIG. 12B is a plan view schematic similar to FIG. 12A illustrating a bar arrangement for placement of alternating colored webs in the same folding lane path for color mixing with different colors from adjacent folding plates.  
         [0026]    [0026]FIG. 12C is a similar plan view illustrating a bar arrangement to place similarly colored webs in the same folding lane path with webs superposed oppositely from the superpositions of FIG. 12A.  
         [0027]    [0027]FIG. 13 is a plan view schematic for supply rolls arranged on both sides of the folding lane paths illustrating bar arrangement to place two like colored webs in each lane, noting the bar extensions beyond outside margins of both incoming and exiting webs.  
         [0028]    [0028]FIG. 14 is a side elevation viewed from  14 - 14  of FIG. 13.  
         [0029]    [0029]FIG. 15 is a side elevation viewed from  15 - 15  of FIG. 14 illustrating double turning bar and web threadup for embossing two superposed adjacent web pairs comprising four product webs.  
         [0030]    [0030]FIG. 16A is a plan view schematic of web travel from supply rolls on both sides of the folding lanes illustrating turning bars arranged to place similarly colored webs in the same lane.  
         [0031]    [0031]FIG. 16B is a plan view like FIG. 16A illustrating turning bars arranged to place different colored webs into the same lane for color mixing with oppositely colored webs in the second folding lane.  
         [0032]    [0032]FIG. 16C is a plan view schematic like FIG. 16B with bars arranged to interchange webs of similar color to lanes opposite from FIG. 16B.  
         [0033]    [0033]FIG. 16D is a plan view schematic like FIG. 16A with colors reversed from folding lanes in FIG. 16A.  
         [0034]    [0034]FIG. 16E is like FIG. 16A with colors reversed from the folding lane placement shown in FIG. 16C.  
         [0035]    [0035]FIG. 17 is a plan view schematic for two supply rolls on both sides of the folding lane path illustrating two superposed tiers of turning bars for color mixing and embossing of two plies (4 product webs) in the upper set of embossing rolls and 2 plies (4 webs) in the lower set for subsequent separation of adjacent webs for placement on one of two adjacent folding plates.  
         [0036]    [0036]FIG. 18 is a side elevation schematic viewed from  18 - 18  of FIG. 17 illustrating the processing means of FIG. 17 including one side of the dual folder.  
         [0037]    [0037]FIG. 19 is an end view of two single folders in side by side dual folder arrangement illustrating selective separation of folding plates.  
         [0038]    [0038]FIG. 20 is a side elevation schematic of a folding plate side shift mechanism viewed from  20 - 20  of FIG. 19.  
     
    
     DETAILED DESCRIPTION  
       [0039]    In FIG. 1, supply roll  1  of color A comprising two product webs A 1  and A 2  passes through slitter  5  and advances along infeed paths  3  and  4  respectively.  
         [0040]    Supply roll  2  of color B comprising two product webs B 1  and B 2  is slit at  5 ′ and advances along infeed paths  3  and  4  respectively.  
         [0041]    The slit product webs enter turning/lane interchange device  6  and exit along folding paths  7  and  8  for subsequent fabricating steps and delivery in stacks.  
         [0042]    Since two supply rolls involve two product webs of each color (4 total webs), color mixing requires two supply rolls, fout slit product webs and four longitudinal folding plates  10 - 13  for delivery as napkin pairs of alternating color from two delivery lanes of folding apparatus.  
         [0043]    Referring to FIG. 8, the bottom web in lane  7  is longitudinally folded by plate  10 , and the bottom web in lane  8  is longitudinally folded by plate  11 . The folded webs are advanced over folding pastes by pull rolls  14 ,  14 ′ and advanced for transverse folding in folders  15  and  15 ′ of dual folder  9 .  
         [0044]    Referring again to FIG. 1, the selected turning bar arrangement shown is enlarged and detailed in FIG. 5.  
         [0045]    In FIG. 2, supply roll  1  for webs A 1 , A 2  and supply roll  2  for B 1 , B 2  are on opposite sides of folding plate lanes  7 ,  8 . The turning bars in turning/lane interchange device  6  are arranged to advance like colored webs A 1 , A 2  to lane  7  and B 1 , B 2  to lane  8 , as more fully detailed in FIGS.  13 - 15  (see also FIG. 16A).  
         [0046]    In FIG. 3, supply roll  1  is comprised of webs A 1 , A 2 , supply roll  1 ′ for A 3 , A 4  of the same color, and rolls  2 ,  2 ′ for different color webs B 1 , B 2 , B 3  and B 4  respectively are all on one side of the folding plate lanes  7  and  8 .  
         [0047]    Slitters  5 ,  5 ′ produce four product webs for turning in apparatus  6 , and slitters  16 ,  16 ′ produce four product webs for turning in apparatus  6 ′.  
         [0048]    Slit webs are advanced by draw rolls  24  (see FIG. 5) for subsequent embossing (not shown), and longitudinal folding by plates  10 - 13  and  17 - 20  before transverse folding in folders  15 ,  15 ′ (shown in FIG. 8).  
         [0049]    In FIGS.  1 - 4 ,  11 A- 11 C.  12 A- 12 C and  16 A- 16 E, only the active surface of turning bars are shown for clarity, however, in FIGS. 5, 13 and  17 , the framework for supporting bars extend beyond the active surfaces because turning bars must clear the outer margins of incoming and exiting web paths. For example, in FIG. 5, the framework must exceed 3 product widths on both infeeds and exit sides to avoid web interference with bar end supports within the active zones.  
         [0050]    In FIG. 4, a tier  6 ′ of four spaced turning bars  21 - 21   n  receive and turn webs from supply rolls  1 ′,  2 ′ which bypass tier  6  for advancement to folding plates  17 ,  18  and  19 ,  20  for subsequent transverse folding and delivery in lanes  22  and  23  of dual folder  9 .  
         [0051]    The turning bar arrangements of FIGS. 1, 5, and  11 A- 11 C are identical and FIGS.  11 A- 11 C describe different web paths including lane interchanges from 7 to 8 or vice versa.  
         [0052]    Different web paths are made possibe by providing vertical spacing between each turning bar to insure that moving web surfaces travelling in different directions do not make contact.  
         [0053]    Webs advancing in opposite directions or moving perpendicular to each other must be separated, whereas webs travelling in the same direction can use the same turning bar and be in superposed surface contact after turning 90 degrees into exit lanes  7 ,  8 .  
         [0054]    In FIG. 5, webs are pulled from turning bar aparatus  6  by draw roll pair  24 . A pair of co-acting water jet cutters  25  are mounted for transverse adjustment on supports  26 ,  26 .′ to slit variable width trim from the center of adjacent webs to create a gap between webs for advancement to upper embosser roll set  27  supported in frame  28 .  
         [0055]    In FIGS. 5 and 6, four product webs are processed simultaneously through exit draw rolls  24  as two superposed adjacent webs advancing in parallel lanes  7 ,  8  (two superposed webs per lane) for embossing, folding and delivery.  
         [0056]    Prior to embossing, center trim is slit by water jet cutters  26  and removed (trim suction fan not shown) to create a gap so that growth through the emboss roll set does not result in overlap of adjacent webs.  
         [0057]    Ex-embosser, transverse web growth beyond target web width over folding plates is trimmed by center jets  31  and edge jets  32 ,  32 ′.  
         [0058]    In FIG. 7, dupply rolls  1 ,  2  are unwound by belts  32 ,  32 ′ in roll inwind stands  33 - 33 ′, slit as at  5 ,  5 ′ and advanced to turning device  6  having framework exceeding three product widths to avoid bar mounting interference with incoming or exiting webs.  
         [0059]    In FIG. 9, incoming webs A 1 , B 1 , advance from infeed path  3 . and webs A 2 , B 2 , advance from path  4 .  
         [0060]    Webs A 1 , A 2  advance to opposite lane  8  above webs B 1 , B 2  which are directed to lane  7 .  
         [0061]    Webs A 1 , B 1  are on the bottom in parallel lanes and webs A 2 , B 2 , are superposed.  
         [0062]    In FIG. 11, this arrangement results in different colored webs A 1 , B 1  being longitudinally folded over plate pair  10 ,  11  (see FIGS. 5, 6, and  8 ).  
         [0063]    In FIG. 10, the bar arrangement is viewed from the infeed side. After turning and proper lane orientation, the four webs (2 pair of adjacent webs) are superposed and pulled by draw rolls  24 .  
         [0064]    In FIG. 11A, like colors A 1 , A 2  are folded over plate  11  and B 1 , B 2  are folded over plate  10  (see FIG. 8).  
         [0065]    In FIG. 11B, webs are threaded differently from  11 A with web B 2  interchangd with web A 2 .  
         [0066]    In FIG. 11C, webs are threaded differently from  11 B with web B 1  interchanged with web A 1 .  
         [0067]    In FIGS.  11 A- 11 C, two unwinds are on the same side of folding lanes  7 ,  8  (see also FIG. 1) and turning bars for all webs are parallel.  
         [0068]    In FIGS.  12 A- 12 C, two rolls are on the other side of folding plate paths  7 ,  8 , are also parallel, and mirror image the turning bar arrangement of FIGS.  11 A- 11 C.  
         [0069]    In FIG. 13, supply rolls  1 ,  2 , are on opposite sides of folding lanes  7 ,  8  and turning bars for each color are perpendicular.  
         [0070]    In FIG. 13, water jet cutters  5 ,  5 ′ are used to slit supply rolls into product webs  
         [0071]    Infeed web travel for adjacent product webs of the same color is parallel, and after turning, like colors are superposed in the same lane and exit from apparatus  6  in surface contacting relationship, A 1 , A 2  in lane  8 , B 1 , B 2  in lane  7 .  
         [0072]    In FIG. 14, two spaced turning bars are used since different colored webs A 1 , B 1  or A 2  B 2  are not in contact, but after turning, webs of the same color are in each lane for side by side longitudinasl folding and processing as a color mixed pair in the dual folder.  
         [0073]    In FIG. 15, incoming webs advance in opposite directions. Bottom webs A 1 , B 1 , are shown dashed and occupy infeed lane  3 ,  3 ′ respectively to advance to the first set of folding plates (see FIG. 16A).  
         [0074]    [0074]FIGS. 16A and 16D have the same turning bar arrangement with webs in  16 D interchanged to lanes opposite from FIG. 16A.  
         [0075]    In FIG. 16B, webs A 2 , B 2  interchange lanes from FIG. 16A.  
         [0076]    When webs travel in opposite directions surface contact and web rupture are avoided by using four spaced bars rather than two bars in FIG.,  11 A.  
         [0077]    In FIGS. 16C and 16E, turning bars for one color are mounted perpendicular to bars for other colored webs.  
         [0078]    In FIG. 16E, webs interchange folding lanes from the positions in FIG. 16C.  
         [0079]    In FIG. 17, supply roll  1  of color ans supply roll  2  of color B are mounted on one side of folding lanes  7 ,  8 . Rolls  1 ′,  2 ′, are installed on the opposite of folding lanes.  
         [0080]    After slitting into product webs, each group of four webs is advanced to turning bars in tier  6  for webs from rolls  1 ,  2 , and tier  6 ′ for webs from rolls  1 ′,  2 ′ . . .  
         [0081]    In FIG. 17, tier  6 ′ is offset and shown dashed for clarityto indicate turning bar arrangement whereas FIG. 18 shows tier  6 ′ in the proper orientation above tier  6 .  
         [0082]    In FIG. 18, both tiers have spaced turning bars to orient sequemtially different colored webs for each set of folding plates.  
         [0083]    Bottom webs A 1 , B 1 , are folded over plates  10 ,  11 , with the next bottom web pair A 2 , B 2 , folded over plates  12 ,  13 , next bottom web A 3 , B 3 , over plated  17 ,  18  and the last web A 4 , B 4 , over plates  19 ,  20  (see FIG. 17 for plate sequence).  
         [0084]    In FIG. 17, adjacent webs are water jet cut as at  26  to cut through overlapped webs and permit transverse web separation  35  by spreader roll  25 .  
         [0085]    Gap  35  occurs prior to embossing and permits transverse web expansion through embosser roll pairs  28 ,  30  without overlap.  
         [0086]    Water jet cutters  31 ,  32 ,  32 ′ are used to trim transverse web growqth from the center and edges of the adacent webs after embossing.  
         [0087]    Jet cutter transverse locations are adjustable (not shown).  
         [0088]    In FIG. 19, trim gap  35  can be adjusted by the amount of web spreading and adjustment of jet cutters. Final trimmed web width must be centered on each folding plate thus, plates are mounted for sideway adjustment.  
         [0089]    In FIG. 20, plate  10  is fastened to plate support  36  which is part of slideable member  37  supported on cross piece  38 .  
         [0090]    Cross piece  38  a threaded hole in each of two screw supports on either side of the plate centerline for adjusting screws  40  and reverse threaded  40 ′. Screws bear against and move the slideable base  37  thus moving attached support  36  and plate  10 .  
         [0091]    It is understood that the present invention may be embodied in other specific forms without departing from the spirit or special attributes, and it is therefore, desired that the present embodiments be considered in all aspects as illustrative and, therefore, not restrictive, reference being made to the claims rather than to the foregoing specification to indicate the scope of the invention.  
         [0092]    Having thus described the invention, what is desired to protect by Letters Patent are the following:  
       Folding Apparatus for Napkin Stacks having Two Color Sequences  
       [0093]    [0093]                                         INDEX FOR RFERENCE NUMBERS                                1   TWO-WIDE SUPPLY ROLL FOR COLOR A       A 1   1-WIDE PRODUCT WEB - COLOR A       A 2   1-WIDE PRODUCT WEB - COLOR A       2   TWO WIDE SUPPLY ROLL FOR COLOR B       B 1   1-WIDE PRODUCT WEB - COLOR B       B 2   1-WIDE PRODUCT WEB - COLOR B       3   INFEED PATH FOR WEBS A 1, B 1       4   INFEED PATH FOR WEBS A 2, B 2       5   WEB S;ITTER FOR ROLL 1       5′   WEB SLITTER FOR ROLL 2       6   TURNING BAR/LANE INTERCHANGE DEVICE           FOR 4 WEBS       6′   TURNING BAR DEVICE - TIER 2 FOR 4           ADDITIONAL WEBS       7   WEB FOLDING LANE PATH - LOOKING IN WEB           DIRECTION       8   WEB FOLDING LANE PATH - LOOKING IN WEB           DIRECTION       9   DUAL FOLDER (COMBINATION OF 2 SINGLE           FOLDERS)       10 &amp; 12, 17, 19   RESPECTIVELY - FOLDING PLATES FOR LEFT           LANE       11 &amp; 13, 18, 20   RSPECTIVELY - FOLDING PLATES FOR RIGHT ″       14   PULL ROLLS UNDER PLATES       15   SINGLE FOLDER FOR LEFT LANE WEBS       15′   SUNGLE FOLDER FOR RIGHT LANE WEBS       16   SLITTER FOR ROLL 1′       16′   SLITTER FOR ROLL 2′       12-20   SEE 1- AND 11       21, 21N   FOUR SPACED TURNING BERS PER TIER       22   DELIVERY LANE 3       23   DELIVERY LANE 4       24   DRIVEN PULL ROLLS AFTER TURNING BAR           SECTION       25   WEB SPREADER ROLL       26   WATER JET WEB CUTTER (SLITTER) PAIR FOR           CENTER TRIM       27   WATER JET ADJUSTABLE SUPPORTS       28   UPPER EMBOSS ROLL SET (2 PAIR OF           JUXTAPOSED WEBS - FOUR PRODUCT WEBS           TOTAL       29   EMBOSSER FRAME       30   LOWER EMBOSSER ROLL SET       31   JET CUTTER FOR CENTER SLITTER, EX-           EMBOSS       32, 32′   EDGE WATER JET CUTTERS       33, 33′   UNWIND BELTS       34, 34′   UNWIND STANDS       35   GAP BETWEEN WEBS IN FIGS. 17, 19       36   PLATE SUPPORT       37   SLIDEABLE PLATE SUPPORT BASE       38   CROSS MACHINE SUPPORT       39   FIXED ADJ. SCREW SUPPORT       40, 40′   PLATE SIDE ADJUST SCREW       41   DELIVERY LANES (SEE FIG. 18)