CA2175037A1 - Method and apparatus of transporting an elongate flexible object and use thereof - Google Patents

Abstract

The invention relates to a method of transporting an elongated, flexible object (1,5), such as a belt, chain, wire or web, wherein the speed of a part of the elongated object (1,5) is periodically varied, while maintaining a constant speed of the upstream and downstream parts of the object(1,5).The method comprises feeding the elongate object (1,5) past transport members (9,11,13,15) such as rotating transport rollers which are oscillated parallel to the elongate object (1,5) in the direction of transport and opposite to the direction of transport. Three sections of the elongate object are during oscillation of the transport members maintained in a mutually parallel relationship. Translation and rotation balancing mechanism allow the transport members (9,11,13,15) to be driven at high speeds and low variations in torque.

Description

WO 95/~2539 2 1 7 5 ~ 3 7 PCTIUSg4/l~
, Metilo~i and Apparatus of Transponing an Elongate Flexible Object and Use Thereof Fleld Qf th^ Jnyrn-inn Th~ invention reiates to a method of transpontng an elongate, fiexible oyect aiong a stationar~
frame. the elongate, fiexible object being transponed aiong an upstream trajecton, a downrucam uajectory, and an intermeoiate uajectory cQmprised between ti~e upstream uajectory and the dQwnsueam uajectory, the metilod compnsing the steps of:
a mQving tbe eiongate, fiexible object aiong the upsu~am uajectory and aiong tile dov~nstream trajectory at a substantiaiiy constan~ speed of transi~on, the upslream and the downstrcam trajectory being substantiaily stauonaly teiatiYe to tile frame, b nutntng the eiongate, fiexible object agong a transpon member tilat is periodicaily dispiaceable, ti~e transpon member itaving an upsuwn and a dov~nstrcam pan, and c periodicaiiy dispiacing the transpon member around a stationaly e~iuiiibrium position.
The inYention furtber reiates to art apparatu.~i for carrytng out said method and to a metbQd of ~ in w_ich the speed of the elongate, flexible object is Yaried in accQrdance v~ith s~id method.
r Ofthrr Such a method and apparatus are icnown from Ei~-A-0 364 087.
In tbe aboYe patent apphcation. a deYice is disclosed for applying layers of materiai irl a direcuon, generaiiy transYersely across a longitudinai v~eb, which web moYes continuously through the device in tbe macbine direction at a I ' ' web speed. The machine direction corres,oonds to t_e longitudinai derection of the v~eb. The de~dce compriSes two transpQIt members VY_ich eacb deflect the v~eb thrnugh 90, in the plane of the vieb. A transYerse v~eb i~onion of constant length.
extending I , - to the machine directton, is comprised betweut the transpon members, which ate fonned by air bars. The transpon members are mounbted on a can w~ich can be reciprocilted in tbe machine direction.
When tile uanspon members are mnvcd in the trarlspon direction of the web. at a speed which eo,uais thc w~b speed. the web ponion between the uanspon members is stationar,~ relatiYe to the transpon members. The uansYerse v eb ponion is irl this case stationan in the direction to the machine direction, i.e. in the cross machine direction. An applicator, Y hich mQYes in synchrQnism with the intenmediate pan of the web in the machine direction. can appiy for instance strips of eiastic materiai to the imtermeoiate pan Qf the web. without mQ~ement of the applicator in the ~ . ' ' directjon. Th~se strips of elastic material extend in the transverse dire~tion of the web.
Upon reversai of the movement of the transpon members, tbe intermediate part of ti e web that extends between tile transport members, is acxlerated past tile downstsream transport member and is fe~i in the macbine direc'dotl.
Aithough ti~e above devix is effective in ch mging the speed of oniy a ~ ;' ' portion of a web, the upstsream and downstream parts beini, run at constant speed, ti~e device introduces to the web portion a net speeti component witich is parailel to the direction of transport of tile web. An appiicator device is tilerefore necessary tb~t moves with tile speed of displacement of the air bars paralid to the transport direction, for the appiication of the transverse fearures to the web. This wiil complicate tile applicator e~iuipment and tbe devix to suppiy the tape to tile appiicator.
Furthermore, for tile web speed of ti e intermediate part of tite web ti at is compnsed between ti e transport members to become zero, the transport members need to be displaced at a speed that e~iuais Lhe web speed. Especiaily at high web speeds. the transport members vill be subject to large .
AnoLher disadvantage of the i~nown de ice. is that the centre iine of Lhe downstream part of Lhe web is displaxd im Lhe ' ' direc~ion, with respect the centre line of the upstream part of Lbe web.
Fmthermore. Lhe above apparatu~ is not f t to be used in combinabon with a web which cannot be deflected into the direc~ion, such as a ci ain.
From US-A ~,399,905 am apparatus for fromdng a stack of ar~icies is know4 in which a flight of grippers are moumted on ar endiess belL The helt is looped aroumd transpon a member, which is re~iprocated so Lbat a part of Lhe be~t is cycGcaily spaL aily stopped, at a conL nuous drive of Lhe helt.
By moveing the transport memher ag unst tbe direction of transport of the belL wiLh the Lransport veiociy, Lhe speed of Lhe belt relaLve to stationary frame of ti~e stacker is stopped.
A disadvantage of Lhe above apparatus is L~at the veioaty of the transpon member needs to e~inai Lhe speed of transpon of the belt for a pan of the belt to become stationaty, Funhermore, the path length of Lhe pan of the belt hat extends between the transpon member and a stationary roller, ch mges upon reciprocauon of Lhe transpon member. Hence, the knovn apparatus can oniy be sued ~ WO 95112539 , 1 7 ~ 0 3 7 PCTNS94/12265 in combination with a chain or a toothed belt but not in combinalion v.ith a nat web of relatively low strength.
- It is an object of present mvention to provide a method of transporting an elongate flexiole object, snch as a Wt, chain or wire. wherein the speed of a part of the belt chain or wire is vaired while ice~ping the speed of the main upstreaun and downstream parts of the belt chain or wire constarlt.
- It is anothcr oyect of the invention to periodically valy the speed of a part of the elongate, flexible object at high frerluencies, while iceeping the speed of the main upstrearn and downstream parts of the elongate, nexible object constant.
- It is another object of the invention to vary the speed of an elongale, flexible object, without causing a deilection of the oyect in the cr^-- ' direction.
- It is ag~un another object of the invention to vary the speed of an dongate. ne~ible object while exerling a low variation in tension on the object.
- It is further object of the invention to vary the s,oeed of a part of an dongate, ilexible object without causing movement of said part in a direction transverse to the direction of transpon.
~ Of~-r The method according to the invention comprises rnnning the elongate, nexibie object aiong a g~Dde member tbat is ' '1~ stationary relative to the frame and aiong a transpon member that is perio~iicaiiy displaceable, the transpon member and the gmde member each havmg an ups= aDd a downstream pan.
A first secuon of the intermediate trajectoq of the nexible elongate object extends between the npstream pan of the glnde member and the upstream pan of the transpon member.
A second s~ction of the intermidiate trajectoq ex-tends betweeD the npsstream and dowDstream part of the glude member or between the upstream pan and the downstream part of the transpon member.
Q113STITUTE Sl ii-ET IRliLE 26 : `

2 ~ 7 5 0 3 7 1-A tilird section of the intermediate trajectoq extends between tile downstreanl pan of ti~e guide member and the downstreaun pan of the transpon member. The first and third section of the intermediatc trajectoq are parailel to tite second section of the intermediate trajector .
Witen tile trarrspon member is reciprocated in a direction parai~el to the second section of the intermediate trajectoq, the lengths of the first and third section of the intermediate trajectoq are varied, whiie iceepimg constant the totai length of the intermediate trajectoq amd wilile iceeping constant the iengtit of tite second of the intermediate trajectoq.
Becanse of the constant length of the intermediate trajectory of the elongate, flexible object, wi~ich will hcreafter be referred to as a "web", tile time it takes for a pan of tile web to traYel aiong the lengtil of the intermediate trajectoq is cnnstant and is independent of the locahon of the intermediate trajectoq relative to the stationaq frame. Hence~ tile movement of those parts of the web tilat are iocated aiong the upstream and downstream trajectories, is not affected by ti~e direction and the speed of the displacement of the intermediate trajectoq reiative to the stationaq fr;tme, the speed at which the web travels aiong the intermediate trajffloq cart be adapted such that for those pasrts of the web that re located aiong the intermediate trajectoq, the velocity relative to tite stationaq frame is increased, reduced, or reversed.
i~elative to the stationaq frame, the second section of the intermediate trajectoq can be stationary or can be i ' ~ dispiaced.
When the second section of the intermediate trajectoq extends between a stationaq npstreatn and a stationaq downstre tm gtnde roiier, the second section is stationaq relative to the fr tme. An embo~iiment of the method according to rhe invention, in which the second section of the intermediate trajectoqu is stationaq, is arrived at by passing tile v~eb aiong a path formed by an upper and a lower S-shaped loop. The bonom ieg of the upper S-shaped loop is comnected to tite top leg of the lower S-shaped loop. Tile f~rst and third sections of the intermediate trajectory corresponds to the combined bOnom leg of the upper S-shaped loop and the top leg of the lower 5-shaped loop.
The stahonaq glude rollers are locLtted in the bottom haif of the upper S-shaped loop and the top haif of the lower S-shaped loop respectivelv. Two transport rollers are ~ocated in the top ha f of the upper S-shaped ioop and the bottom haif of the lower S-shaped loop respectivelv.
The incoming web is fed from the upstream trajectoq, past the upstream transport roller to the upstream glud roller, continues past the downstream g~ude roller to the downstream transport roller S~IBSTITUTE S~iEET IRULE 26) ....... ... . . ...

~ WO 95/12539 PCT/U
_5_ to the downstre~un trajectory. By moving thc transport rollers in thc trarlspon direction of tile incoming ~eb at ilaif the web speed. tile incoming web is stored aiong the increased iength of ti~e top ilaif of the upper S-shaped loop. The pans of ti~e web that are locasted aiong the middie legs of tile upper and iower S-sitaped ioops. are tilen stabonary reaitive to the fr~une.
By moving the trarlspon rollers ag.unst the trarlspon directioD, the lengtil of web tha~ was storeo aiong tile top i~aif of the upper S-shaped loop is accelerated aiong the second section of tile interrnediate trajectory, and is fed to downstream trajectory of the web.
The first embodiment in wilich thc second section of the intermediate trajectory is periodicaily translated relative to tile stationary frame can be arrived at: ' ' the positions of the transpon roiiers and the glud roiiers in tile above upper and iower S-silaped loop ~ 5~, In tilis case, wi~en the transpon roiiers asre moved against ti~e direction fo trarlsport of ti~e incoming web at ilaif the web spd, pan of the incoming web is stored aiong the first trajectory, and pan of the incor~ing web travels aiong the second trajectory at haif the web speed, in the transpon direction of the web As the second section of the web. the position of the web relative to the frame is again stationary, A preferred embodiment of the method according to the invention, in which the secoDd section of tile intermediate trajectory is transiated, compnses feeding the web in a ~ fi" ' which is formed by a first S-shape loop and a re~erse S-shaped loop, which are comnected in a back-to-back manner via their lower legs, Ti~e transpon rollers are located in the lower haives of each S-shaped loop and the glude rollers are located in the top haives of each S-shaped loop.
The first and third sections of the intermeoiate trajectory correspond to tile middie legs of both S-shaped loops and tile second section of the intermedrate trajectory corresponds to the combined lower legs of the S-shaped loops. The advantage of the above: 5~ ' , is that the upstream and the dovmstream trajectones of the web are iocated in the same plane and that the centre line of the downstream trajectory is not displaced, It is essentiai in the method according to the invention, that the first and third secuons of the intermediate trajectory are parailel to the third section The term "parailel" is intended to include cnrvilinear trajectories, thje l , ' ' distance between which is constant, For instance, ail sections of the intermediate trajectory may be located aiong straight lines, or the first and third sections of the intermediate trajectory may be located on segments of a f rst circie, the second section being iocated on a segment of a second circle, which is concentnc with the first circle, Oniy when the parailel relationship between the first and third sections on the one hand, and the second ~BSJLME. SHEET iRliLE ~!fil . .

section on tho otber han4 is maintained, will the total length of the intermediate trajeclory be constant, independent of the position of the transpon member.
By periodically varying the speed of the transpon member with an amplitude of half the sPeed of transpon of the web. the speed of the web relati~e to the frame periodically becomes zero, in three 1. .1~ ..1;. .~ -- direchons. This allows operationS to be performed on the web by applicator apparatus irlteractingh with the web. the applicator apparatus being positiomllly stabonary relative to tbe frame.
As the maximmm spe~d of the transpon members can h limited to half of the web spee4 of less, in oroer to temporarily stop the web, the method c~m be applied at high web speeds, while maintaining the acc~lerations of the tram;pon memb~r relabvely small ~n the method according to the invention, the centre lines of the upstream and the downstream pans of the web are not displaced m a 4iJection parallel to the plane of the web. This allows the method to be used in production hnes through which the web passes in a straight line, without having to realign the downsueatn pan of the production line, or the use of an extra deflection member to realign the centre liner of the downstream pan of the web. r ~ ~ ~ flexible objects, which are not flexible nn a direction ~ , ' ' to their length, such as chains, can be slowed down by the method according to the inven~don.
In an embodiment of the method according to the mvenbon, the gmde memhrs amd the transpon membus each comprise two rollers that are rotated by a drive mean~i to reduce the strain exened by the transpon member on the web.
For a web sufl'lcient strength, pulling the web at const mt speed of - , past the reciprocating transpon members, will cause the pan of the web located along the second section of the mtermediate trajectory to be peno~dcaJly slowed down, to be stopped or to be reversed. In this case. the transpon memhrs and the gLude memhrs can comprise smooth cylindrical bars or air bars. When the elongate. flexible object is formed by a chain, the gmde members csm comprise spmcket wheds. For webs of dabvely low strength, such as paper webs, ~dssue webs. fibmus batts or ~ ' ' thereo driving of the transpon mllers and the glnde mllers assures exeration of a mnnimal strain on these webs. The glnde rollers can be driven at a const mt speed, such that their ' ~ velocity corresponds to the transpon velocity, Vo, of the web. The transpon mllers need to be driven m synchronism with their penodic speed of ', ' t, VT, so that their r -' ~ vdocity varies periodically between Vo-VT, and Vo+2VT-SUBi~llTUTE ~HEET (RULE 26) -~ WO 95/12539 2 1 7 5 Q 3 7 PCT/US94/12265 An apparatus for canying out the method according to the mvention comprigs a stationalv frame.
m upslream imd a downstream cylindrical guide member connected to the frame iD al! stationaly = er. each guide member hanng sm axis, the axes bemg generally parillld, am upstream and a downstream cylindrical transport member, the axes of which are generally parallel to the axes of the glude members, the cylindrical smface of the upstream glude member and the upstream cylmdrical surface of the downstream glude member and the downstream trimsport member being substimdalb tangent to a second plane, which is substsmtially parallel to the fist plame, amd the cylindrical smface of the glude members or the transport members being substsmtially timgent to a third plame, located at a spaced apart locabon from the first plime amd the gcond plame, amd drive melms commected to the frame for penodically displacing the transport members tangentially along a third plane which is parallel to the first and gcond planes, in a substsmtiasly straight lind generally, , " ' to the axes of the transpon members. aroumd am equilibris~m position located gencrally midway between the axes of the glude mems~ers, the distimce hetween the axes of the trimsport members being constimt.
Wh~n the third plame is located between the first and the gcond plane, the web is fewd past the transport roilers in am upper amd a lower S-shaped loop 5,, The top leg of the lower S-shaped loop is conmected to the bonom lef of the upper S-shaped loop.
In tlDs fi~, the first section of the intermediate trajectoq is located in the first plime which compnses the middle leg of the upper S-shap~d loop. The third section of tbe intermeoiate trajectoq is located m the second plane which comprises the mDddle leg of the lower S-shaped loop amd the tbird section of the mtermediate trajectoq is located in the third plane which compngs the bonom leg of the upper S-shap~d loop and the upper leg of the lower S-shaped loop.
In a preferred embodiment of an slpparatus according to the invenhon, the first plsme amd the second plane are coincident, the intermediate trajectoq being pan of a double S-shaped loop comprising a first, invened S-shaped loop amd a second, S-shaped loop which are connected via their lower legs.
Preferably tDe transpon members are mounted on a sled which is reciprocated along the frame.
An embodimenl of the apparatus m accordance with the invention compnsesme}ms which are rotationally coupled to the transpon rollers, the . uL~h~.. ' ' ' 3 means being compnsed of a two discs WhDch are rotationallv mounted on the frame. Each disc is linked to a psur of pullas by a belt. The pullas are comnected to the sled on which the transpon rollers are SUR~SllTI ITF SHEET l~lllLE 21~

- -momnted, onc puilq of each pair bing driven by a respective tramspon member. A beit forms a closed loop around each disc and the respective puilqz. when the sied is reciprocated, the puilqs are translated within each closed loop of the baiancing means, so that toe speed of rotation of each disc differs in phase from the speed of rotation of the transport members by 180, i.e. the speed of the discs incr~ases when the speed of the transport members decreases and vice versa. This ailows the combtned transi~ort members and baiancing meams to be rlm at constant rorqDe by a drive motor drinng tbe rotation baianceing means and the transport members. Coupling of the transport members to baiancing discs ailos high speed mevement of the sled, for instance at a rate of 550 rpm and a ~ , ' ,, high rate of variation of the speed of the transpon rollers.
A futther embodiment of the spparatus according to the invcntion, comrises driving the glude rollers and the transport rollers by a singie, endiess drive beit or chatn, a part of which runs paraiiel to the mtermxiate trajxtory. By moving the pan of the drive bGlt or chain that Qrresponds to the downstream trajxtory of the web, at the constant speed of transpon Vo, the intermediate trajectory of the dirve hlt is run past the gmde roilers with constant speed Vo, and past the transpon rollers at a periodic speed of amplitude bet~een VolVT. amd Vo+2VT
Preferably the sled cartying the transpon members, is suspended from the frame by a ,I cnmprising two verbcai arms, a lower end of each arm being Qnnectxi to a respecbve end of the SlXt, each venbcai arm being at its upper end hingingly Qmnectxd to the frame.
Ailowing the slxd to swing on the frame obviates the need for iinear bearings, and ailows for reciprocabon at relariveb high speeds nsimg a simple drive mxhanism such as a, ', 1,.
canblever. i'referably tile ampiitude of reciprocabon of the sled c3n easiiy be adjustsed by varying the distance between the pivot pint of the cantiiever and the point of QmnectiOn nf the cantiiever to the sle~ The c;mtiiever can be Qmnected to a ' ' ! ' ' " means to maintain a generaily Qnstant positbon of the centre of ma55 of the combined bi,mcing means, the sied and the canblever.
To ensnre tilat the sled follows a substanbaiiy honzonbai path of travel, rather tbatn an arcuate trajectory, the sled is preferabiy suspended from the frame by means of a Eivans lini~age.
The method of appararus acQrding to the invemion can ~ be used in a process, wherein an oyect i5 assembled of treated on amoveing Qnvqor belt, the si~eed of the blet bing varied at the po5ibon of a work stabon for execubon of an assembiy step or a processing step, without affecbng the speed of the upstream and downstream pan of the belt. E~-amples of such processes are found in assembly lines such as for microchips, cars. radios, pacicing iines such as for SIJBs~TuTE SPi~ET IRULE 26J

~ WO 9~/12539 2 1 7 ~ 0 3 7 PcT~us941l?~6s filings of bags, hottlcs of boxes, automatic maciDining oAf a series of products, p nnting or printing or coating of a moving belt or wcb or objccts placcd thereon.
TlDe metltod amd apparatus according to the invention can especiallv bc applicd in tiDe - Dv of absorbcnt products elDrerin the elongate, flexible object is forrned by a continons wcb comprising a topshect, a backsheet and an absorbent corc of relatiYely low tcar strenglDD. TlDe web is fcd pan am applicator stabon to have parts such as for instancc dastic membcrs, or a wain shield attachcd to it in a dircction (crDss machine dircction) transvcrse to tlDe feed direction.
Temporarily nopping the web USDng tlDe apparatus accordidng to tlDe invcntion, allov s attachment of parts in tlDe cross maciDinc direc~ion at higlD speed amd low strain on tiDe v cb, withont tiDe nccd for complex ~ripper means tlDat movc witiD the same speed as thc web.
AnotiDer application of the metlDod ~md apparatus according to tiDe invention can be tlDe applicabon of a perr,Dancnt deformation to tiDe topshect and/or the baci~shcet of an abNrbent product nsing positionaliy stationary, corrugated members, to impart extensibility to the topsheet and the hacksheet.
Rrirf r of the r Figure I shows a schematic side wlevational view of an embodiment of tiDe apparatus according to the invention, Figures 2a, 2b amnd 3 schematicaly show ' " of an apparatus according to the invcntion, whercin the intermetiiate trajectory is translatcd, Figure 4 shows the spccd of tiDe slcd, transpon rollers and weo in the apparatus of figures 2a and 3, Figures 5 and 6 ~ show embodhlDents of the apparatus according to the invention wherein the intermetiiate trajectory is i '~ nationary, Figurc 7 SiDows the spe~d of the sled, transpon mllers and web in the apparatus of fignres ~ and 6, Fignre 8 shows a schematic perspectiv~ view of the apparatus according to the invention, Figure 9 shows a schematic perslDective view of the ~ v means and the rotation-biancing means, Figure lOa and lOb '~ show the fimciioning of the . ' ' 3 meams Figure 11 shows a ' ~I.~...h,.~l view of the i ' ! ' _ mcans.
Flgures l_a-12d ~ show the fnnctioning of tiDe i ' ' ' _ meams, Fignre 13 ~ ' '', shows the fimctioning of the , carrying the sled, Figure 14 shnws a perspective view of the dine mechamism for rotating the dnve rollers and the gmde roliers, .'~iSTlTUTE Sl IEEr (RULE 26) WO 95112539 PCTiUS94/12265 0 ~ l 1 5 3 3 7 -lo-Figure 15 shows the apparatus according to tile in~enuon in an air-laying process for foaming an absorbent core, Figure 16 shows a schematic frontai view of a diaper ' _ iine comprising the apparatus according to th~ invention, Figures 1 7a and 17b show schematic side views of the application means for imparting regions of extensibiiiy to the web, and Fignre 18 shows a plan view of a diaper proviced with regions of extensibiliy nsing the apparatus of fignres 17aamd 17b.
i?~ of the InV~-n~inn Figure I shows an apparatns for transporting a flexible, eiongate object 1. With flexible it is meant that the obe~t I cna be transported aiong a cnrvilinear trajectory and will adapt its shape so as to conform to the trajectory. The object I c~m be made of ilexible materiai, snch as webs made of paper, airfelt, piatic etc., or c~m be rnade of rigid segments that are hingingly lini~ed in a chain ~ e manner. The elongate, flexible object can be i . :' 1, but can aiso be a .' structnre, such as a wuc, thread or rope.
The web I is transported aiong upstrearn trajectory 3 with a constant velociy of transpon~ Vo, in the machine direction F. The upstre~un trajectory 3 is formed by the lenght of the web I which extends to the right of the first gmde member 9 in fignre 1, amd which is moving towards the infecd side 4 of the apparatus. After passing through the apparatus, the web I exits at the outfeed side 6 and is transported at constant vlocity Vo aiong the downslreaun trajectory S, which extends to the left of the gmde member 11. The upstream and the downstream trajectones need not correspond to the machine direction, and can be formed by straight-line or cnrviiinear i~aths.
The guide mcmbers 9 ~md 11 are qiindricai bodies such as ~ . r bars or air bars, but arepref~rably forrned by rollers which are rotationaily cormected to the frame 35. The glnde rollers 9, 11 have a fixed position. The web I is looped around am upstream and a downstream transpon memberl3,1Swhichareformedbyrollers,thataremountedonasledSl.Theslcd41isqclicaily tr~mslated aiong the frame 35 aronmd the cqnilibrium position 39, in a direction generaily paraiiel to tbe machine direction F, by drive motor 36 An intermediate trajectory 7a, 7b, 7c of the web I is located between the upstream gmde roller 9 and the downstre~un glude roller 11, amd compnses a first section 7a and a third section 7c, of variable length, located betweerl the upstream glued roller 9 and the upstreiun transpon roller 13 and the downstream transpon roller 15 and the downstream glude roiier 11 respectively. The second section S~lBSllTUTE S~iET (FWLE 26~

2 1 7 5 ~ 3 7 CrNS94/12265 -Il-7b of the intermediate trajectory is located between the transport rollers 13 and 15 and is of constant length.
Beacuse of the summetty of the intermediate trajectory 71, 7b, 7c. the increase i n length of the first section 7a, upon displacement of the sled 41 opposite to the machine direction F and away from the eo,uilibrium posidon 39, is compensated by an equai decrease in length of the third section 7c, and vi3 versa. As the length of the second section 7b is constant, the ~ ' ' ' ' trajectoly 7 is of constant length. Hence the time for the web I to travel past the intermediate trajectory 7a, 7b, 7c is independent of the position of the sled 41 with respect to the frame 35.
When the part of the web ti~at is located aiong the sec~nd section 7b of the intermediate trajectory 7a, 7b, 7c is stationary reiabve to the frame 35, the web I is contacted by applicator means 29, 29', 38, 38' wilich are positionaily stationa~y with respect to the frame 35. The appiicator means compnse a pair of verticaily displaceable tampers 29, 29' which press the web 1 ag nnst the iower partw 38, 38' of the applicator means. After the appaiicator means have interacted with the web 1, tile web I is accelerated aiong the section 7b of the intermediate trajectory towards the outfeed side 6 of the apparatus 2, and is suppi ied to the downstream trajectory 5 with web speed Vo.
The gnide roilers 9, 11 and the trasnport rollers 13, 15 are driven by a drive member nn the form of a close~ loop 50 and puileys 52, 53 and 54. The loop 50 is partiy parailel to the intermediate trajecto y 7a, 7b, 7c. The loop 50 is driven at a constant speed which is equai to the speed of , Vo, of the web 1 by a single dnve motor 51. By driving the gmde rollers 9, 11 and the transport roilers, 13, 15, the strain exerted on the web 1 is minimised and can be limited to the acceleration forces, which are acting to change the speed of the web.
Figures 2a, 2b and 3 iilustrate ' ' ' in which the intermediate trajectory 7a, 7b, 7c is transiated with respect to the stationary glame 35 . In the embodiment of figure 2a. the gl~id mentbers 9, 11 and the transport members 13, 15 are arranged in a double S-shaped loop in whdch a lefihand, reverse S-shaped loop comprising the dwonstream g ude loller 11 and the downstream transpon roUu 15, is coMected via its bottom leg to a righthand S-shaped loop comprising the upstream transport roller 13 and the upstream gmde loller 9.
Intheembodimentoffigure2b.tbesled41comprisestwop~ursoftransportsrollersl3,13'andl5, 15'. The inermediate trajectory 7 compries the part of the web I which is located between upstre~un g ude roDer 9' and do~nstream g ude roller 11'. The web I is stationar,~ relative to the frame 35 along section 7b of the intermediate trafectroy 7 when the sled 41 moves ag~unst the direction of transport, F, with a velocity of Vo/4. The addition of n pairs of g ude lollers to the fralne 35 and n S~J8SrlTUTE SItEEr ~YJLE ~ _ _ pairs of transport rollcrs to the sled 41, allows toe speed of the sled 41 to be Kduced to Vo/2n to stop the motion of tbe web I along secUon 7b. Hence, the web, I can be rlm at a Klatdvely low, although the constmction of tbe sled becomes more complicated upon addition of extrea p~urS of transport rollers In tbe embodiment of figure 3, the transport members amd the guide members are configured n an upper and lower S-shaped loop. Upon displacement of the sled 41 in the upstKam diKction (opposite to the direction of transporL F), parallel to the sections 7a, 7b amd 7c, the first section 7a of imtermediate trajectroy is elongated. Generally the diKction of displacement of the sled 41 will corKspond to the direction of transport, F, in which the web I is transported towards tbe input side 4 of the apparatus. However, as is indicated in figure 2a. the web I can be transported towaros the input side 4 and away from the output side 6 at amy desuable angle, the direction F being for instance vertical as indicated by the broken lines in figure 2a.
A part of the imcoming web is stoKd along the incKased length of section 7a. The pans of the incoming web that calmot be ' ' along the increased length of secdon 7a, slip past the upstream transpon roller 13, na teh downstream transpon roller 15 and glud roller 11 to the downstream trajectory 5. At the downstream sid the sechon 7c is shonened by the same amoumt by which secdon 7a is incKased The length of web located along the decKased length of section 7c is also passed to the downstream trajectory ~.
When the sted 41 moves ag~uM tbe direcdon of transpon F at a speed VT, tbe incKase length of section 7a, shp past the upstream transpon roller 13, via the downstream transpon roller 15 amd g~ude roller 11 to the downstream trajectory 5. At the downstream side, the section 7c is shonened by the same amount by which secdon 7a is increased. The length of web located along the decreased lengtb of secdon 7c is also passed to the downstream trajectory 5.
When the sled 41 moves ag~unst the diKction of transport F at a soeed VT, tbe increase in length of tbe section 7a in a ~ ' ' time interval, is proponional to VT m. In the ~._ ' ' ' time interval, the length of incoming web I is proportional to Vo m. wherein Vo is the conslant vdocity of transpon of the web I along the ups= and downstream trajectories 3, 5. The rate at which the web slips past the upstream tlanspon rolle~ 13 in the direction of transpon. is equal to Vo -VT, which is the relative speed of the web I with respect to the sled 41 and the transpon rollers 13.
15. As the sled 41 moves at a speed VT against the direction of tr;mspon, tbe relahve velocity of the web, Vw, rdative to the stahonary frame 35 is equal to Vo -2vT~
S~JBSTlTlJTE SHET ~IUJLE 2~

-~ WO95/12539 2 1 7 5 0 3 7 PCIIUS94/12265 At the downstream side. the decrease in length of section 7c is proportionai to VT m. This length of web is supplied to the downstream trajectory 5. Aiso supplied to the downstream trajector,v 5 is iength of web. siipping past the transport rollers. 13. 15 v,~hich is proportionai to Vo-VTm. so that the totai length snpplied in the, ~' ' time intervai to the downstream trajectorv 5 is proportionai to Vom. Hence. the velocity of the web I aiong the downstream trajector,v 5 remains nrlaitered, and is independant of the speed VT of the sled 41.
It foiio~s that if the sled 41 moves ag~unst the transport direction F, at a rpeed etiuai to haif the rpeed of transport of the web I (Vr-Vo/2), the web I travels aiong the second sechon 7b of the intermediate trajectory 7 at the rame rpeed at which the section 7b is moved aiong the frame 35.
Hence, tile net displacement of the web aiong the second section 7i~, relative to the stationar,v frame 35, is zero. If the sied 41 moves ag~nnst the transport direction at a speed VT which is slower thar, haif the speed of transport, Vo/2, the web I is slowed down reiative to the frame 35. aiong the second section 7b of the intermediate trajectory 7a,7b,7c. If the sled 41 moves at a speed, VT, faster tilan haif the speed of transport, vOr-. the speed of the web aiong the second section 7b of the nntermediate trajectory 7 is reversed reiative to the stationary frame 35, and is directed against tile transport direction F.
Ui~on reversai tlf the speed of the sled 41 in the direction of transport F, the length of section 7a is in a L :' ' time intervai shortened by a length wilich is proportionai to VT m. This length of web, as weii as a length pmi~ortionai to Vo m of incoming web, travels past section 7b of the intermediate trajectory 7. As section 7b itseif travels at VT m/s past the frame 35, the rpeed of the wei~ 1, Vw, relative to the stationary frame 35 etiuais Vo +2VT in the direction of transport, F. AT
the dowr,lstream side. tite section 7c ilas increased by a length which is proportionai to VT m in Is.
This iengtil of web, as well as a iength proportionai to Vo m tilat is to i?e transported to the dowDstream trajectory 5, needs to be Nppiied past downs= transport rolier 15. Eience the speed with which the web needs to be snppiied past the downstream transport roller 15, corresponds to the speed of the web aiong section 7b (Vo+vT m/s), In hgure 4 the speed of the web I relative to the sUtioDar,v frame, Vw, along the second section 7b of the intermediate trajectory 7, has been graphicaiiy indicated for a c,vclicai speed of the sled 41, VT, with an amplitude Vo/2, etiuai to haif the velocity of transport. The speed of the web relahve to the second section 7b of the inermediate trajectory 7 has been indicated as VR. VR corresponds to the ~ velocity of the ttansport roilers 13 and 15. It can be seen tilat the speed of the web VW aiong section 7b, reiative to the sUtionarv frame. is in phase with the speed VT of the sled 41 aDd varies aronnd the consUnt speed of transport Vo between O and twice the constant speed of transport. The r " ~ speed of tho transport roilers is aiso in phase with the speed of the ded 41 and varies aronDd Vo between Vo/2 and 3Vo/2.

WO 9S/12539 PCT/US94112265 1~

Fii,ures 6 and 7 show cmbodiments of the apparatus 2 in which the second sechon 7b of the intermediate trajectory 7 is i ' "~ stationary relative to the frame 35.
Moving th~ sied 41 in Fiigure 5 in tile transport direction F at haif the speed of transport. causes the upstrGun trajectory 3 and the section 7a to be increased in length. The incoming web I is stored aiong this increased length, so that the speed of the web aiong section 7 b is stationary. At the same time, the downstream trajectory 5 and the section 7c are shortened, and the parts of the web that were located aiong these sections are suppiied to the downstre~tm trajectory 5.
Reversai of the moment of the sled, causes the web that was located aiong the increased lengtils of the upstream trajectory 4 and section 7a, to be accelerated aiong section 7b to the downstre~tm side 5.
The embodiment of the method and apparatus as shown in figmre ~ wori~s according to the same principles as the embodimem of fignre 5. In figure 6, the sections 7a and 7c of the intermediate trajectnry 7, are located on a first cyiindncai snrface aiong transport roller extcnsion = 55,57.
The second section 70 of the intermediate trajectory 7 is located on the surface of a drnm 59. Upon moving of the sled 41 ~ "~ with the axis 61 of the drnm 59, in an ' ' direction,the lengths of the section 7a and the npstream part of secbon 7b are increased. The iengths of the downstream side of section 7b and the third section 7c are decreased in length such that the combined lengih of sections 7a amd 7c as weil as the length of section 7b is coristant.
When the transport roiiers 13,15 are moved with the sied 41 in a F ~ ' bme intervai aiong a section of the ~ of the drum 59 which is proportionai to haif the vdocity of transport, nbont haif the incomini~ web is Roreci aiong the nncreased length of section 7a and about haif the incoming web is Rored aiong the increased upstrcam part of section 7b. The velocity of the web aiong section 7b, reiative to the frame is constant, in fif,ure 7, the web speed, VW aiong section 7b and the r ' ' ~ speed VR of the transport roiiers 13, and 15 are given for cyclic displacement of the sled 41 aiong a trajectory concentric with the axis 61 of the drum 59, with a velocity VT hanng an amplitude of haif the speed of transpon of the web. The r r ~ speed of the transpon rollers is indicated ns VR. When the drum 59 is rotationaily comnected to the frame, the ~ ' speed of the drum will correspond to the web speed, Vw. The velocity and phase relationships of Figure 7 aiso apply to the embodimeM of Figure 5.
SLIBSl~TUTE Sl~iEET ~LE 2~

~ W095/12s39 2175337 pCTlUS94/12265 Fii,ures 8 amd 9 show a persp~ctive view of the embodiment of Ihe apparatus in which the gmde rollcrs9,11andthetr,msportrollersl3,15arerotationailymountedonthesled41.Thesled41is suspended from the frame 35, wilich i~æ been ' "~ indicated in these figures, bysuspension means 79,79'. The sled 41 is driven by a cantilever 71, which is pivotably connected to the sled in a drive point 73. The tr,msport rollers 13,15 are connected to rotation baiancing means 63,63' which ailow the transport rollers to be driven at a constant torque. i n the embodiment of figure 8, the rotation bai mcing me~ms drive a rotating baiamcing mæs 62 via a closed loop member such æ belt or chain 64. The bai~mcing means rotate with the same rotationai vclociy æ the tr.msport roiiers to wilich they are connected, ar~d are ' '~ translated within the closed loop member 64. AS a consequcnce the baiancing mæs 62 is rotated in synchronis~n with the transoort roll~rs but in thc opposite direction to the direction of rotation of the transport roliers.
Hence the resuit;mt torque of the baianbng mæs 62 and the transport rollers 13,15 is consiant.
in a preferred embodiment of the invenuon, the rotabon baiamcing means 63,63' each compnses a disc 65,65' which is rotatably comnected to me frame 35. This is shown in figure 9 For each disc 65,65' two puOeys 67,6g and 67 and 69' are mounted on the sled 41. A belt 70,70' is loopeii aromld the baiamcing disc's 65,65' altd tile puileys 67,69,67',69'. The puileys 69,69' are each coupled to the axes 25,27 of the transport roOers, 13,15. The ! - ' ' speed of the puiieys 69,69' is equai to VR. t/R ~herein r is the radius of the puileys 69,69' and R is the radius of the transport rollers 13,15.
The functioring of the baianbng means 63,63' æ shown in figure 9 has been ' ''~
indicated in figures lOa amd lOb. In figures lOa amd lOb, the posibon of the sled 41, hæ been indicated at its equilibrimm posiion 39 in solid iines and at a posibon close thereto, in broi~en bnes.
When the sied 41 is fmthest from Its equiiibrium posiion 39 (a posibon which has not been indicatedinfigmeslOaandlOb),thesled41,andwithittilepuileys67,69,are ' " "~
stabonary. The stabonary posibons of the s~ed 41 can for the embodiments of figmes 2a2b and 3, be found in figure 4 at positions O,T/s and T of the x~;is. For a statbonary sled 41, the belt 70 is driven by puile~ 67 such tilat the speed of the disc 65 in bis cæe is equai to tile C~ speed of the puiley 67. Wilen the speed of the sled 41, VT, is zero, it c~m be seen from figure 4 tilat the ~ ' speed of the transport rollers, VR, is equai to the speed of transport, Vo. For the cæe in which tile radii of the pullevs 69,69' are equai to the radii of the transport rollers 13.15, the ~ ' speed of the disc 65 equais Vo.
When the sled ~1 is close to its equilibrium posibon, and is moved in the direction of traosport, F, from ti~e position indicated bv thc broken line in fignre lOa to the position indicated by the solid SLU3S~TlJrE_SI-i~ET IRllLE 26) . . ..

~NO 95112539 PCTIUS94/12265 ~

liDe in Fig I la tDe speed of the sled , . 'S equals Vo/2. This siruation can be found arouDd time T/4 on the x-axis of figure 4. When pulleys 67 and 69 are in a prc;'~ ' time interv~
displaced by a distaDce proponioDal to Vol2, a length of belt 70 propor~ional to Vo (the broken-line pan at the right-haDd side in Figure 10a Deeds to be transponed past pulley 69 to pullq 67 to take up the slack. No rotation of the disc 65 is necessary. However, as can be seen from Figure 4, the rotational speed of the transpon rollers aDd the pulleys that are driven by the traDSpon rollers, equals 3Vo/2. therefore. in addition to the length Vo of belt 70 that is moved past tDe pulleys 67 aDd 69 upon traDslation of the pulleys, aD ad~Dtional length Vo/2 of belt 70 needs to be supplied to pulley 69 by rotation of the belt 70 past the disc 65. Hence the rotational speed of the disc 65 is proponional to Vol2.
Whcn the sled 41 is close to its equilibnum positioD, and is moved against the direction of transpon F. the speed of the sled again about equals Vo/2. This situation is found arouDd time 3T/4 on the x-axis of Figure 4, aDd is illustrated in Fig 10b. Considering ag~un a displacent of the pulleys 69 aDd 67 proponional to Vo/2 in a p-- :' ' time interval, it can be seen that a length of belt 70 which is propordonal to Vo needs to be taken up by rotation of disc 65. From figure 4 it c,m be seen that the speed of the pulley 69, which is driven by thc transpon roller 15, equals Vo/2, so that in tbe given time interval an additional length of belt 70, proponional to Vo/2, is accumulated at the upstream side of pulley 67. Therefore, in addidon to the lengtb proportional to Vo that is to be passed from pulley 67, via the disc 65, to pulley 69, the pulley 67 supplies a length of belt 70 to disc 65 which is proponional to Vo/2. Hence the speed of rotation of the disc 65 is proponional to 3Vo/2.
As appears from the foregoing discussion, the rotahon of the disc 65 varies with the same frequencsl asthetransponrollers 13,15andwithafixed 180phasedifferencewiththespeedofrotationofthe trar~lspon rollers 13,15. Only when the radii of the pulleys 69,69' are equal in length to the radii of the transpon rollers 13,15 will the amplitudes of the ~ ' speed of the disc 65 be equal to me 6peed of the transpon rollers, VR. By adapting the mass distribution of the discs 65 to the moment of inenia of the tran6pon rollers, the overall variations in torque of the combined tran6port rollers 13,15 and the discs 65,65' with respect to an axis of the drive motor 51, can be mdnimised.
Hence the dnve motor 51 will not be adversely affected by the I ,,' ' , changes in rotatiom~l vdocity of the transpon rollers.
Figure 11 show6 a s;~i ' ' view of the ' ' ! ' 1,, means 77, which i6 formed by a rotating mass balance that compnses two rotating balancing masses 80,81. The sled ba~ancing means 77 comprise6 a hou6ing 87 having an inner circular track 85. The housing 87 is attached to SLIBSIlTLlTE SHEET ~RULE 26) ~ WO 95/12~39 2 1 7 5 0 3 7 PCT/US94/12Z65 the frame 35. and is stadonary with resi~ect to the frame. The cantilever 71 is at its upper end commected to the baiancing masses 80 and 81.
Rotating mass 80 compensates tile inenia forces tilat are exened on the cantilever 71 by the sled 41 such tilat the sled the cantilever amd the baiamcing means can in combination be driven at a const~mt force. The sled 41 performs a honzontai periodic motion and is accelerated amd decelerated by the cantilever 71. The sled 41 exens a penodic force on the cantiiever that is proportionai to ti~e acceleration and that is iargest when the speed of the sled is 0. Ti~e horizontai component of the force exened on the cantilever 71 by tbe rotating mass 80 is aiso periodic amd i~as tbe same fre~iuency as ti~e freonency of reciprocation of ti~e sied 41 is e~iuai in magmtude to the force exened by tbe sled and is directed in the opposite direction. The mass 80 is driven for instance by a drive sbaft 84 at a constant rotationai speed. The verticai component of the force exened by the mass 80 on the housing 87 is compensated by the mass 81 that travels np amd down aiong straight-iine path A-C.
The mass 81 is mounted on a disc 83. having a diameter eqnai to haif the diameter of the circuiar track 85. The disc 83 is mtationaily mounted inside the housing 87 and travels aiong the circuiar track 85. The disc 83 may be formed by a pinion the arcular ~ 85 being provided with meshing gear teeth. The position of the baiancing mass 81 amd the disc 85 at position B of the circniar track 85 have been iDdicated in Figure 11 in broken lines. Fnnher rotation of the disc 85 to position C of the circuiar track 85 wiil move the centre of mass l.~iB aiong the line AC from the centre of the circuiar track 85 to point C. Fnnher rotation of the disc 83 via position D back to A
moves the centre of mass i~iB back aiong iiDe AC to position A.
In figures 12a-12d it is - 1~ iiiustrate~i how the mass baiancing system 77 interacts with the sled 41. The housmg 87 comprismg the circuiar track 85 is commected to the frame 35 amd is StatioDary with respect thereto. A drive shaft 84 which exteDds to the plaDe of the drawing amd which passes through the centre of the circuiar track 85 mtates the mass 80 at a constant rotationai speed. The disc 83 is at its centre rotatably commected to the mass 80 such that npon rotabon of the mass 80 the disc 83 is rotated aiong the track 85.
Upon rotation of the disc 83 aiong the track 85 the points of the ~ of disc 83 that are located in positions to point A and to the centre of the track 85 in f~gure 12a move aiong straight-line paths. that are diametricaily locate~i with respect to the circuiar track 85.
SLJBSllTlJTE S~i~ET ~IY iLE 26 , 21 7~037 -Iti-The cantilever 71 is connecteo to a linkage which is hingingly comnected to the ~ of the disc 83 in a point J which in figures 12a and 12c coincides with the center of circuiar track 85. The drive shaft 84 drives the mass 80 and the disc 83 al a constant rotationai speed. As shown in f~gures 12a arld 12c. the sied 41, which has been ' ' 'lS indicated, is in its e~iuilibrium position.
Since the sled 41 is suspended from the frame 35 via the ~vams linkage (which has not been shown im f gures 12a 12d) the sled does oniy exert honwntai inertia forces on point J. As the accelerauon of ti~e sied 41 is 0 in its e~iuilibrium position, no horiwntai forces are exened ~y the sied on point J
in this posihon. The verticai force exer~i on the housing 87 by the rotating mass 80, is in this position compensated by the force exerted by the mass 81, which is acceierated towards the center of circuiar track 85.
Upon rotation of the disc 83 m the direction of arrow Q, the point J moves aiong a straight-line i~ath from the center of the tracic 85 to point B. The bai~mcing mass 81 moves from position A to tbe center of track 85. When the c;mtiiever 71 and the sled 41 reach their maximum deflection amd the sled is to aeeel~rating in direction of arrow Fs, the horizontai inertia force exerted by the sie~i on poiDt J is at its iargest and is direeted opposite to the direction of arrow Fs. The horizontai CompOneDt of tile force exerted OD the housing 87 by rotating mass 80 is aiso at is maximum vaine aDd is directed in the direction of arrow Fb, aDd compeDsates the force exerted on the point J by the sied 4 1.
Tile mass 81, wilich in Figures 12b aNi 12c has i~een indicated by the broken liDes, is located in the ceDter of eircniar track 85, aDd moves at maximum, constant speed. Hence, no inertia force is exerted by the mass 81 on the housDng 87.
Upon fmther rotation of the disc 83, the mass 81 reaches i~oint t_, reverses its direction of straight-line movement, and travels back to the CeDter of traek 85, as has been shown iD figure 12c. The forces aetmg on the housimg 87 amd point J in figme 1 2c and 12d are identicai in magmtude amd oppoSite in dDrection to the forees that act in the position of the sled 41 as shown in figure 12a aDd 12b respectively.
The weight of the baiaDcing mass3 80, 81 amd he distaDces of the baianQng mass3 form the drive shaft 84 wiil depend on the actuai configuration of the sled 41 and the cantilever 71, amd caD on the basis of the above priDcipies easily be determined. The pnnciples of tile ~ of the sied 41 is aiso applicable to , in which the c mtilever 71 is driven by other means thaD the wtating drive shaft 8~.
SLlBS~TiJTE ;I EET lRULE 261 ~ WO 95112539 ~) 1 7 5 0 3 7 PCr/US94~12265 The snspension means 79,79' as shown in figures 9 and 10 comprise a Evans linkage, the pnnciple of which ilas been ' ' '',~ indicated in Figure 13. In the Evans linicage, a verticai stlSpension arm 89 is suspendefi in rotation point 87. The sled 41 is suspended at the lower end 96 of the stlspension arm 89. Rotation of the verticai suspension arm 89 around ti~e rotation point 97, causes the iower end 96 of the arm 89 to follow a circuiar wtation path 101. In ower to havc the lower end of the arm 89 move aiong a straight-line path 105, the centre of wtation 97 neetis to be dispiaced npon wtation of tile arm 89. Tile suspension arm 89 is thereto commected to a wtahon arm 86, which in figure 13. for the verticai posibon of the snspension arm 89, is located behind the suspension arm. The wtation arm 86 is wtatable awlmd wtation point 95. and positions 91 and 94 of the wtation arm 86 ilave been indicatefi. The length of tile rotation arm 86 is of gencraily haif the length of t~uspcnsion arm 89.
When the wtation arm 86 is moved to position 91. the lower end of the snspension arm 89 can be located on circuiar path 106 which is indicated by a broken iine. The lower ~nd of the suspension arm 89 v/ill be located on straight-line path 105 for position 91 of the wtabon arm 86 when the upper cnd of the suspension arm 89 is in a hinging point 108 connected to a transverse arm 93. As the transverse arm 93 is of relatively largc radius. and the angle of wtation of the arm 93 is reiatively smail. the path of the hinging point 108. which is part of thc circniar path 103.
~i ~ ' ' corresponds to thc verticai displacemcnt of the uppr enfi of the arm 89.
Via the suspension = 79. the sled 41 can be reciprocated aiong a snbstandally straight line path 105 withont the need for linear bearings. This ailows the sled to be reciprocated at a high speed without intensivc maintenance re~inirements to the bearings of the suspension means.
~ urel4showsaperspectivenewofthedrivemechanismforrotatingthegnidewllers9.lland the transport wiier 13.15 in accordance with the speeds as shown in f gures 4 anfi 7. The drive member50.whichiscomprisedofabelt~ispassedawmnddriveroiiersllO,112,114andll6.aiong a path which is paraiiel to the web 1. The dtive wllers 110 anfi 114 are etiuai in diameter to the glude wllers 9 and 11. amd wtatc at a constant ~ elocity Vo which corresponds to the velocity of the upstream and the downstream parts of the web I . The drive wllers 112 and 116 are e~inai in diameter to the transpon rollers 13 and 15. amd wtate with a cyclic speed of amplitude Vo/2 around the speed of transport Vo. The belt 50 is passed aiong puileys 11 3 and 111 and forms a closed loop.
Thepnileyll3isdrivenbyadrivemotor.51.ataconstantspt~edVo.Duetothereciprocationof the transport wllers 13.15. the belt 50 passes aiong these wllers at the above fyclic speed. The beit 50 drives the glude wllers 9.11 at the constant speed Vo.
SIJBSTlTlJTE SllEET (RULE 2 WO 95/12539 2 ~ 7 5 0 3 7 PcTlus94ll2265 o The method and apparatus according to tile invention can be applied to a wide variety of processes in which a belt, chain or wire is moved al a constant speed and in which a pan of the process involves a manipuiation of the belt, chain or wire, or of objects carried thereby, al a different speed.
The object which is transponed c;m for instance be a chain or belt v.~hich is transponed in an endiess loop at a constsmt, average speed and which passes throngh the apparatus according to the invention. In tilis case, the g~nde roilers and the transpon rollers need not be driven. The chain or beit csm be pan of a drive mechanism or gear system for a funher apparatns. The glude members amd transpon members need not be cyiindricai, but can for instsmce be of polygonai cross-section.
The chain or beit can comprise gripping means that project from the sides of the chain or belt, amd which are displaced in the cross machne direchon relative to the glnde rollers amd the transpon rollers to be able to pass aiong side the transpon rollers and the gmde roiiers, rather th~m between them. At the position of the applicator means, 38 the objects carried by the belt or chain c;m be combined with other objects, assembled, packed, machined, painted, pnnted or otherwise treated.
The apparatns and method according to the invention are panicuiarly suited for transponing objects of a relativeb weak tear strength such as paper webs of fibrous ceUniosic diaper cores, amd chsmging the soeed of these objects at high freqnencies without any strain being exened on these objects. The paper webs c m be stopped to be pnnted or psunted at the applicator means 38.
For the diaper cores, wilich comprise batts of finff pulp tbat are compnsed between a liquid i~nperYious backsheet and a liquid pervious topsheet the cnres can be slowed down at the applicator station for different pmposes The appiicator means c;m comprise noz~ies for deposition of absorbent gelling materiai onto the fibrntts batt if the absorbent gelling materiais are deposited at a constsmt rate, varying the speed of the batt past the nozzies resuits in a longitudinai variation of the absorbent geUing matenai in the diaper cores. Appiicator mes~ns for supplying absorbent gelling materiai are described in US-A-4,523,274 issued to i~iauider et ai. on September 24, 1985 amd Emopean Patent EP-B-0 380 675.
In a core-forming process for air-laying at batt of oellniosic fibers, the apparatus can be conflgnred as sbown in figure 15. The fibrous batts 190 can be transponed on a foraminons beit, 178 which is passed by the apparatns according to the invention. The applicator means csln comprise a vacunm suction box. 180 canying the batts past the transpon rollers and the guide rollers and a fiber lay dov~n chamber 192 located above the vacuum suction box. The speed of the foraminous belt 178 can be varied to be adapted to the rate of deposition of the fibres onto the forammous belt. The speed of SLBSnTUT~ S~iEET RULi 2~ ,. .. .

~ WO 95/12539 2 1 7 5 0 3 7 fibrous batt 190 in the fiber lay-down chamber 192 catl for instance be decreased as more fibres ar~
deposiled onto the foraminous belt and the rate of deposition decreases Figure 16 shows a schematic froùtal view of the apparatus 2 according to the invention amd the applicator meams 38 for applying a pre-stretched strip of elastic material 161. such as a lamirlate elastie rnaterial, to the web 1. such as for instance a waistband or waistcap 154. The direction of trarlsport of the web l is r . " ' to the plane of the drawing. The elastic material 161 is ultwound from a roll by a metering element eomprising two rolls 159,160. Roll 159 is driven at slower speed than roll 160, 50 that the strip of elastic material is pre-stretched, The elastic material is fed aiong an automadc trachng system 162 to minimise Yariatiorls in the position of the center line of rnaterial 161 at the metering point that is located at the infeed point of the rotating vacuum belt 163. A glue coater ~64 '~ coates the elastic material with a contirluotls, or spiral-patterrled layer of glue. The pre-5tretched elastic material 161 is tightly held on the perforated conveyor 165 by action of Yacuutn suction box 166. The rotating conYeyor 165 passes the dastic materiai by a crush i~nife 167, and sub5e~iuentiy rotates the elastic materiai in a paraliel position to the we'o 1. The web is stopped by the apparatus 2, and the air cS linders 29,29' as shown in figure I
push the web I ag~dnst the eiastic element 161. Each air cylinder comprises a tamper foot. After a shon dwell-time (a few " ', the air cylinders 29, 29' are moYed upwards, the web I is accelerated in the direction of transport. Upon actnadon of the air-cylinders 29,29', the Yacumm acting on the pre-stretched da5tic materiai is switchxd of by means of a mechanicai switch, bloeicing the access of the apenures in the conYeyor 167 to the vacuum sucdon box 166. The movement of the tr.mspon rollers 13,15, the mxhanicai Yacuum switch of the Yacuum suction box 166, the air cylinders 29,29' the giue coater 164 and the icnife 167 are aii synchronised to maintain the proper phase relationship between the different movements.
Figure 17a shows an embodiment in which the applicator me~ms 38,38' comprise a pair of corrugaledmembers 170,171 haYingintermeshingteeth,forphysicailydeformingtheweb 1. When the corrugated members 170,171 are clamped down on the web 1, bhe web is deformed aiong paraliei iines, , " to the corrugabons which in this case extend 1~ - to tbe piane of drawing. The web has increa5ed extensibilit,Y in the direcbon 1 1 -- i .~ -- to the iine5 of the ' ~ the web I being after contacbng with the corrugated members 170.171 dongatable in a ~ " fashion. By stopping the web 1, reiabve to bhe corrugated members 170,171,acompleXpanernOfdeformaboncanbeappliedtothewebwhichpatternhasa component in the transYerse direebon of the web, 50 that the weo is elongatable in the machine dirxbon. Using the apparatus according to bhe invenbon maices it is possible to proYide bhe leg ponbons 172 of the diaper, a5 is indbcated in Figure 18~ with increased extensibility. Preferably, an elasbc eiement is compri5ed between the topsheet and bhe bacicsheet of bhe diaper in its reitixed state WO 95112539 PCTIIIS94/12265 ~

in the areas of defornnation. Pnor to contacting the web with the members corrugated 170,171, the web I cannot be substantiaily eiongated. After contacting the web with the corrugated members 170,171, the areas of the web I in which the elasdcs are located are activated, and become dasdcaily extensible.
The physicai deformation can aiso h applied in the longitndinai direction of the web 1, for instance in the area of tbe side paneis 158, or the waist areas, ~73, 175 as shown in figure 18.
A i~nown method for applying physicai deformations to impart extensibility to a web is commoniy referred to as "ringrolling~. Ringrolling involves passing the moving web between the nip of two roiiers tbat are provided with r corrugations. The axes of the rollers extend in the rr~r~ direction of the web. Another form of "ringroiilng" involYes the use of fiat corrugated members, of the type shown in Figures 17a and 17b of the present application. The above method, as weii as siructnres prodnced thereby have been described in detail in US-A-5,196,000 issned to Ciear et ai. on lviarch 23, 1993; US-5,167,897 issned to Weber et ai. on December 1, 1992; US-A-5.156,793, issued to Bneii et ai. on October 20, 1992, in pardcular Figure 5, in combinatdon with the desdption, Colnmn 20; and US-A-5, 143 ,679, issued to Weher et ai. on September 1, 1992.
The method and apparatus according to the invention ailow slow-speed deformation of the weh 1.
Henx the impact-times of the corrugated members on the web can be longer so that the physicai deformation can be bene~ controlled and the energy imparted to the web can be more gradnaily distribnted.
The apparatus according to the invention can be used to provide complex deformauon panerns to products of the type described in the above patents. The physicai deformation imparted by the method amd apparatns according to the invention, can be so confignred to impart extensibility to the whoie of the absorbent product, snch as the combined topsheet, bacicsbeet and core, or to oniy portions thereof, such as to the laterai wings of a sanitary napicin as descnbed in US-A-4,687,478, issued to Van Tilbnrg on Angust 18, 1987.

Claims (27)

Claims

1 Method of transporting an elongate, flexible object (1) along a stationary frame (35), the elongate, flexible object being transported along an upstream trajectory (3) a downstream trajectory (5), and an intermediate trajectory (7a, 7b, 7c) comprised between the upstream trajectory and the downstream trajectory, the method comprising the steps of:
a moving the elongate, flexible object (1) along the upstream trajectory (3) and along the downstream trajectory (5) at a substantially constant speed of transport, the upstream and the downstream trajectory (3,5) being substantially relative to the frame (35) b running the elongate, flexible object (1) along a guide member (9,11) that is translationally stationary relative to the frame (35) and along a transport member (13,15) that is periodically displaceable, the transport member and the guide member (9,11) each having an upstream and a downstream part, such that - a first section (7a) of the intermediate trajectory (7a,7b,7c) of the flexible elongate object (1) extends between the upstream part(13) of the guide member and the upstream part of the transport member (13,15) - a second section (7b) of the intermediate trajectory (7a,7b,7c) extends between the upstream part and the downstream pan of the guide member (9,11) or between the upstream part and the downstream part of the transport member(13,15), and - a third section (7c) of the intermediate trajectory (7a,7b,7c) extends between the downstream pans (11,15) of the guide member (9,11) and the transport member (13,15),the first section(7a) and the third section (7c) of the intermediate trajectory (7a,7b,7c) of the elongate, flexible object (1), being parallel to the second section (7b) of the intermediate trajectory (7a,7b,7c) c periodically displacing the transport member (13,15) relative to the guide member (9,11) around a stationary equilibrium position (39) in a direction substantially parallel to the second section (7b) of the intermediate trajectory (7a,7b,7c) of the elongate. flexible object (1), while keeping constant the length of the intermediate trajectory (7a,7b,7c) and while keeping constant the length of the second section (7b) of the intermediate trajectory (7a,7b,7c)

2 Method according to claim 1, wherein the periodic speed at which the transport member (13,15) is moved relative to the guide member (9,11) has an amplitude of 1/2n times the speed of transport, so that the elongate flexible object (1) along the second section (7b) of the intermediate trajectory (7a,7b,7c) is periodically stationary with respect to the frame(35). wherein n is a natural number.

3 Method according to claim 1, the transport member (13,15) comprising two transport rollers which are rotated by a drive means (50,51) such that the strain exerted by the transport member (13,15) on the elongate, flexible object (1) is reduced.

4 Method according to claim 1, the guide member (9,11) comprising two guide rollers that are driven by a drive means (50,51) such that the strain exerted by the guide member (9,11) on the elongate, flexible object (1) is reduced.

5 Method according to claims 3 and 4, the guide rollers (9,11) and the transport rollers (13,15) being driven by a drive belt or drive chain running along the guide rollers (9,11) and the drive rollers (13,15) generally parallel to the intermediate trajectory (7a,7b,7c) of flexible object (1).

6 Method according to any of the previous claims, the transport rollers (13,15) being connected to a balancing means 63,63', such that variations in torque exerted by the transport rollers are reduced.

7 Method according to claim 6, the transport rollers (13,15) and the balancing means (63,63') being driven in combination, at constant torque.

8 Method according to any of the previous claims, the transport member (13.15) being connected to a translation balancing means (77), the combined centre of mass of the transport member (13,15) and the translation balancing means (77) being kept substantially stationary.

9 Apparatus (2) for carrying out the method according to any of claims 1 to 8. the apparatus comprising:
a stationary frame (35) an upstream and a downstream guide member (9,11) connected to the frame (35) in a translationally stationary manner, each guide member (9,11) having an axis (19,21). the axes (19.21) being generally parallel, an upstream and a downstream cylindrical transport member (13.15), the axes (25,27) of which are generally parallel to the axes (19,21) of the guide members (9,11), the cylindrical surface of the upstream guide member (9) and the upstream transport member (13) being substantially tangent to a first plane (29), the cylindrical surface of the downstream guide member (11) and the downstream transport member (15) being substantially tangent to a second plane (31) which is substantially parallel to the first plane (29), and the circumferential surface of both guide members or both transport members (13,15) being substantially tangent to a third plane (33) which is located at a spaced apart location from the first plane (29) and the second plane (31) and which is parallel thereto, and drive means (36,71) connected to the frame (35) for periodically displacing the transport members (13,15) generally perpendicular to the axes (25,27') of the transport members, around an equilibrium position (39) located generally midway between the axes (19,21) of the guide members (9,11), the distance between the axes (25,27) of the transport members being constant.

10 Apparatus (2) according to claim 9, wherein the first and the second plane (29,31) are coincident a distance between the axes(25,27) of the transport members (13,15) being larger than a distance between the axes (19,21) of the guide members (9,11) and wherein the transport members (13,15) are displaceable along a substantially straight line.

11 Apparatus (2) according to claim 9, wherein the first and the second plane (29,31) are coincident, a distance between the axes (25,27) of the transport members (13,15) being smaller than a distance between the axes (19,21) of the guide members, and wherein the transport members (13,15) are displaced along a circular path.

12 Apparatus (2) according to claim 9, the two transport members (13,15) being connected to a sled (41) which is mounted on the frame (35) so as to be movable relative to the frame (35).

13 Apparatus (2) according to claim 12, the transport members (13,15) being rotatable around their axes (25,27), each transport member being mechanically coupled to a rotation-balancing means (63,63') comprising a rotatable disc (65,65'), the phase of the rotational speed of which differs by 180°, or a whole multiple thereof, from the phase of the rotational speed of the transport members (13,15), so that the transport members (13,15) and the balancing means (63,63') in combination can be rotated at a constant torque.

14 Apparatus according to claim 13, the rotation-balancing means (63 ,63') comprising for each transport member (13,15) a rotatable disc (65,65') which is fixed to the frame (35), and for each disc (65,65'):
-two pulleys (67,69; 67',69') connected to the sled (41), one pulley (67,67') being driven by a respective transport member (13,15) and -a belt (70,70') fed around the circumference of the disc (65,65') and around both respective pulleys (67,69; 67',69') to form a closed loop.

15 Apparatus according to any of claims 12, 13 or 15, the sled (41) being suspended from the frame (35) by a suspension means (79,79') comprising two vertical arms (89,89'), a lower end (96,96') of each arm (89,89') being connected to a respective end of the sled (41), each vertical arm (89,89') being at its upper end hingably connected to the frame (35).

16 Apparatus according to claim 15, the upper end of each vertical arm (89,89') of the suspension means (79,79') being connected in a hinging point (108,108') to a first side of a transverse arm (93,93), the transverse arm (93,93') being at a second side hingably connected to the frame (35), each vertical arm (89,89') being hingingly connected at its midpoint (97,97') to an upper end of a further vertical arm (86,86') that extends generally parallel to the vertical arms (89,89') and has a length generally half of the length of the vertical arms (89,89'), a lower end of the further vertical arms (86,86) being hingably connected to the frame (35).

17 Apparatus according to claim 9 the guide members (9,11) and the transport members (13,15) each being rotatable around their axes, the apparatus comprising a drive member (50) which is run along the guide members (9.11) and the transport members (13,15) to form a closed loop a part of which extends parallel to the intermediate trajectory (7a,7b,7c) and a drive motor (51) driving the drive member (50) at a constant speed and a constant direction of rotation.

18 Apparatus according to claim 9. the drive means (36,71) comprising a reciprocatable cantilever (71), connected to the frame (35) in a pivot point (75), the cantilever (71) being connected to the sled (41) in a drive point (73).

19 Apparatus according to claim 18. a distance between the pivot point (75) and the drive point (73) being adjustable.

20 Apparatus according to claim 9. the sled (41) being connected to a tranlation-balancing means (77) to maintain a generally constant position of the centre of mass of the combined translation-balancing means (77), the sled (41) and the transport rollers (13,15).

21. Method of assembling an object comprising at least two components, the method comprising the steps of:
-transporting a first component of the object in accordance with the method of any of claims 1 to 8, and -contacting the second component with the first component when the first component is at the second section (7b) of the intermediate trajectory (7a,7b,7c).

22 Method according to claim 21. characterized in that the first object if formed by the elongate, flexible object.

23 Method according to claim 21, characterized in that the first object is transported by the elongate, flexible object.

24 Method according to claim 22, characterized in that the first object comprises a paper web, a fibrous batt, a liquid-pervious topsheet, a liquid impervious backsheet or a combination thereof.

25 Method according to claim 24, the method including in a diaper-manufacturing process any of the following steps or combinations thereof - applying an adhesive to a web - applying a tape fastening system to a web - applying an absorbent gellng material to a web - applying a waist features to a web - applying a reinforcement strip to a web or - imparting an increased extensibility to a web or to a part thereof.

26 Method of applying a material to an elogate flexible object (1), or to an object transported thereby, the method comprising the steps of -transporting the elongate, flexible object in accordance with the method of any of claims 1 to 8, and - applying the materiel to the intermediate position of the elongate, flexible object when the elongate, flexible object is at the second section (7b) of the intermediate trajectory (7a,7b,7c), from an applicator means (38,38') which is positionally stationary relative to the frame (35).

27 Method of treating a moving elongate, flexible object (1), or an object placed thereon, the method comprising the steps of - transporting the elongate, flexible object (1) in accordance with the method of any of claims 1 to 8, and - treating the elongate, flexible object (1) or the object placed thereon at the second section (7b) of the intermediate trajectory (7a,7b,7c) with a treatment means which is positionally stationary relative to frame (35).