CA2009220A1 - Multi-layered hollow-chamber sheet and method to produce such sheet - Google Patents

Abstract

Abstract Multi-levered hollow-chamber sheet and method of producing such sheet The proposed object of the invention is a multi-layered hollow-chamber sheet made of thermoplastic material and consisting of parallel layers removably connected through webs . Each surface of each layer is smoothed so that the result is a hollow chamber of high optical quality.

Description

~` 200922c~

Deocrlptlon Multl-layo~ed hollow-ch~mb~r ~h~t ~nd m~thod to produoe o~ch ~h~t.
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h- lnvention rel~te~ to a multl-lAyered hollo~-aha~b~
~ho-t m~d~ ~p of thormopla~t~c m~t~rlal and lnalud~ng ~Ar~ lay~rs whlch m~y ~ as~mblod b~ m~n~ of w-b~.
~he ~nYon~lon al~o r~l~t~ to ~ m-thod o~ ~od~olng multl-l~yo~od hollow-~hamb~r ~heet.

U~11 ~w-~hJ-mh~r qh~-~ q A~ ~ m~ ~ hy ~Y~ ~n -~r~ ~l ly n~
polymothyl m~th~cxylAte, polyca~bonate, polyothyl~n- and ¦ Pol~vlnyl chlordo~ Tool~ fltt~ng tho c~o~ tlon of the ~hoet ~ro ~ed ~n tho ext~ualon p~oco~o to produoo tho l~yor~ ~nd the wobo or dl-t-nco olemont~ conneatlng thom.
Whon tho hollow Jtr~nd 1~ tho xtru~lon oF~tla-, th-,,,,",,,, ", ,, ;",, , ,:,, ,.,,.".. ,,,-.", " ~ ,.,,. -, ~ ~ ~, . ~ .,;

ln~ YU U~:~b ~Y ~1~J1 ~bl'~b ~A.~jto~tt~ey~ U ~11A~K~ & CLERK ~007 -~ 2 0 0 9 2 ~:) .

matorl~l pa~lng ~ va~uum shau~ng chann~ cooled down belo~ 40ftQaing tomp~r~tur~.

Hollow-chomb~r or wobbnd mult~ple ~heets have ~rovod th~r ~o~th ~ ~ ao~ o~ctlv~ snd bro~ Q~l~tAnt ~b~tltut~
tor multlple-glA~ roo~lng o~ ~roen hou~o~, wlnSer garden~, ~ymn~ me or fox th~ glaz~ng o~ lndu~rl~l bulldlng~.

Howe~e~, the prevlou~ly known hollow-~hambor ~heet~ ~u~-r ~om ~ho dL~dv~n~a~o ~h~t t~oy optlcally dlffer from gl~zing, due ~o tho ~act that t~chnlc~l m~-n~ ~u~t-d ~or ~a~- productlon ~re not ~v~ bl~ ~or omoothlng ~ho ou~-~and inner ~u~f~c~.

Qb~t of th- lnv-ntl~ ~
: ' ~ho ob~-c~ o~ the ln~t~nt inv~ntlon 1~ to ~mprov~
hollow-chambo~ ~heet o~ tho klnd ro~orrod to ~bove ~o that lt h~ adequate optlc~ o~-rtL--, that ~, b- ~
tr~n~pa~ent ~ gl~, and that lt ma~ ea~lly bo ~d~u~ted to tho d~lr-d K ~alue~. ~lgh ~s~n~e ~hould ~l~o be provldod whlch would allow ko onl~r~- tho d~tance~ ne~dod to ~pport the hollow~chamb-r ~heo~- Fln~lly, hollow-oh~mbe~ ~h~-t- hoult ~l-o be capable o~ tr~n~por~ ln comp~cted ~orm.

he ob~qct acccordln~ ~0 the ln~entlon 1~ ~ub~tAntlally ~oh~a~od by ~mooth~ng both ~ldQ~ of ~oh l~y-r, ~lth al~m~nt~ x~-n~lng ~om ~t loa~t on- ~U~o- of oach l~yor, ~ch ~l~m-nt~ dlr~t~y or lnd~r-ctly b-lng ., r ,, " ~ ~ " " ~ u `,LL~
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: conneoted to the layers uoed to f~rm the hollow-cn~mb~r 8l~0e.
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.j J.n 4th-r wordQ, unliko th~ pr~vlou~ .nown pxodu tlon technlques, th~ hollow-ch~mber ~h~t 1~ not produc~d by extru~ion a~ a lngle ~nlt, bu~ 1~ mAd~ up o~ component part~ whlch, ln turn, ~re p~oduc~d as ext~ude~ BhApe~ A~
t ~he ~lde w~ll, th~ , th~ ~u~face Of e~ch l~yor, ~ whlch f~c~B ~nothe~ lde w~ll, h~ pro~a~lng ~ctlon~
.'~ whlCh~ wh~n the hollow-ah~mber ~h~e~ 1~ a~e~blQd~ ~re p~rt~ o~ th~ webbln~ the ~ect~on- ~ub-t~n~l~lly run ~, perpendlcul~r to the laye~ ~u~fa~-~, lt 1~ no longer dl~tlcult to a~l-nd-r bo~h ehe ln~ld- and the out~ld~ by ro~ o a~ to obtaln Sho d--lred o~tlo~l qu~llsy, thaS
mooth~d ~rfAce~. ~h~ only th~nq now r-quLr~ thAt th~ calonder roll~, whlch ~re ~ t ~long the ~obbod ~ld-~¦ o~ th~ layo~ Je ~ro~ ~p~ce~ ln thc r~glon ot the ~i~ elo~ont~ to b~ ~dded to th- web~, ~uah ~p~oo~ ~xt-ndLng por~endLcul~r to the ~xl- o~ rot~lon o~ ~uch roll-. . -,., ;
~ Th~ hollow-ch~mb~r n-~t ~ccord~ng tO the ~n~-ntlon m~y .~ b~ d~lqned not only ~ ~ wQbb~d doubl~ ~h~-t~ ~ut kowl~o ~ a ~bbod multlplo h-et. ~h~- mor-ly r~qulr--! th~t th~ lnn~r l~yor~ h~v~ ~ctlon~ ~ro~o~ting from both s~dQs ~nd ~upplementln~ the conn~o~nq ~ob~.

In o~d~r to v~ry the K vnlu~ ~ do~lred, the ~-ct~on~
~ ormlng the wob~ m~y ~l~o b~ m~l~d by ~oc~lng lnto .~ pl~. Thl~ ~e~mlt~ ~o v~ry th~ dl~t~nc- b-tw--n tho l~y-r- to th~ ~Xt~nt d~lr~d~ whlch ~g~ln h~ ~n lmp~ct on the ~ ~lu~. -.'~ .
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i .1 ~/ ~CCOrdlng to anoth-r embodlment, a ~ree end o~ ~n el-m nt or ~ectlon ~ro~ectlng ~rom th- layer h~ v~r~l oppos~t~ly dl4t~nc~d lock~ng pro~eatlon~, wh~ch ~re ~i mAtch~d by corre~pond~ng roaes~ dl-po~-d ~t th- fr-e end Of the other el~mant or se~lon. ~hl~ l~plle~ th~t tho ti~n~ ~xt-ndlng from A l~ya~ m~y ~or exAm~Lo h~ A
fl~-con~ ~hap~d aro~ e~tlonal geomet y w~lch ~
oalat~d with A rQC~ 0~ the ~eatlon of th- othor layer, ~uah ~co~ havlng A co~ ondlng lnn-r ~-ometry.
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Tn ~nothor embodlm~nt tho roo ond o~ a ~ectlon h~ th-~ha~ o a bead~ elnfo~o~m~nt whlch 1- 4~00001~tod wlth ~ roco~ ln th- free end of the oth-r oeotlon.
,, ~ ~n addlt~on to thl~ mod- of aonnoatlon, ~hl~h 1-j ~g~lvAl-nt to ~n ~embly 0~ A p~ttlnq togethor, t~e l~y~r~ m4y o~ cours~ b~ wolded o~-r tho ~ro~ectlon~
j ~t~ndlng ther~rom.
l . .
~ccordlng to an mbodlment de~lgn-d by th~ lnventor~ tho web conn~atlng th~ l~y~ h~ emo~blo portLon whlch coop~r~te~ wlth ~ho ~-ct~on- ~xton~lng ~rom th~ l~y~r~.
~hl~ ha~ th adY~nt~g~ that by ~ more ~x~hango o~ th~
~moYnhlR ~t.1nn ~hfl ~l~tfln~e b~tw~en the l~yer~ o~n be V~ t, and th- lay~r~ tog~th~r w~h ~h~lr ~ec~lon-~n--d not be d~or-ntly Jh~pod. ~hl~ h~- t~ oclal ad~ntag~
th~t ~h- dl~tance botw-en the l~y~r~ o~n b~ varlod.
Con-oq~ontly, tho l~y-rs of the hollow-oha~b-r ~h--t h~v~
sg~r dl~t~no- ~n tholx o~ntr~ lon th~n ln th-l~
ond roglon~. ~ho r-~ult 1~ that tho c-~ryln~ cap~clty ot th~ hol~ow-ch~mb-~ ohoot 1~ lncroa-~d and~or th~t th-up~x~lng dl~t~na~- c~n be ~nl~rg~d.

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~ s ., i B~ it ~l~o noted th~t ~h~ web~ n~ed no~ ~on~ o~ th-~m- materlal ~ th~ o~ th~ lay~a. ~ctlona ot th~ w-b may b~ m~de of m~tor~ whlch, ~or ox~mplo, hav~ a hLgh-r ol~otl~lty or ~tr~ngth ~han She thermopla~la matQrLal, ~i ~o th4t ~h~ mbly or rRmoval of tho lndlrldual l~yer~
prQsent~ no p~obl~m.

In uartloular, tho uebo aonnoohln~ ~ha l~yo~!~ aonolo~ o~
;~1 pro~ectlon~ llnoA~ extendlng th~x-~om And h~Yln~ beAd-llk- end~ and o~ web-llke element~ conn-atlng ~a~d '~ pro~ctlon~, ~ald el~m~nt~ ha~lng rec~ to r~cei~ th-b-ad-like end~. Tho~o ond~ may ~o obtaln-d by formlng th-ho connector elemont~ whlch, vl~wed e~tlonally, are H-shap~d, s~1d ~lomen~ hav~nq op~o~Ltely dl~po~od ~nd ~ctlon~. ;
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., ~3 In ordQr to ellmln~te the unploa~nt nal~e ~od~od by ~ultl-l~y~d hollow-chamb~r ~hoet~ when ~-Jom~lod o~ ~ut ~ogeth~r, sAld nol~ b-lng du- to ~ r-latl~ ~o~ nt two~n the ~-~lou~ l~y-r- ~nd th- ~onn-ctln~ web~, th~
w-b-lL~e aonneotor plec~ or ~l~ment~, whlah m~y ha~o ~n H-~h~-d cro~ ctlon, ~re, at l~t ~n ~l~co~ olo~oly conn-ct-d for ex~mple by ul~r~wund or hl~h ~r-qu~nc~
'~3 oald ~onno~tor ~oc-~ ~omo~bly oonnooted wlth the ol-ment~ ~xt~nd~ng from the l~yer~ and th~ lln~rly nd b~ad-l~ko dl~po~d pro~ctlon~.

Another ~dY-nt~go o~ th~ multl-l~y-r~d hollo~-ch~b-r ~h~o~ ~ocord$ng to th~ lnront~on lo th4~ lo~ e~ac- ~
oo~upl~d ln Sr~n-port, a~ the ~arlouo lay-r~ m~y b-~conomlcally ~t~C~ d, ~nd ~ mblod upon ~rrl~l at th~
~r olt-.
~ ~ ' '~ ' ' r'.

IJ~ U~.) V;~ J IJ1IJ1 ~ lUU~ I,ul I ~ tll IIU ~ IlAkh~ ~ ~;L~t~k .

i ¦ 6 'I
,o~ d~sc~lDtl~ tbe dr~w~n~

Furthe~ d~tall~ dvPntag~ and ahar~a~ce~1~tlc~ ot th-~~nv~ntlon r~oult not only fro~ ~che elAlm~, th~
ab~Actsr~t~cs derlved ther~rom - ~ln~ly ~nd~o~ ~n combln~tlon -, but ~l~o ~rom th- ~ollowlng d~McrLptlon o~
tho ombodlmQnt~ ~hown ln the dr~wlnq.

i ., Fl~. 1 la ~ J~atlonal ~ w o~ a w~-bb~d doubl- h.~t wlth dlf~er~ntly d~ ned w~b~.

Fl~. 2 1~ ~ p~rt vl-w o~ ~ pre~err~d ~mbo~m~nt o~
.~ w~bb~d doublo l~h~et, Fl~. 3 ~ A Y~rlAnt Or th~ w~bb~d doubl~ o~ ohown ln ~lg. 2, ~nd .~
Flo . 4 1~ a ~ch~m~tlc vlo~r o~ how th- ~ur~-c-à ol yor~ o~ w-bb-d doubl~ or mult~pl~ ~h-ot- ~e amoot~d .

;~ D~t~Ll-d d~c~lotlon~L~
i rlg. ~ ~a ~ ~e~tlonol vl-w o~ ~ W-bb~ doubl- ~h--t ~10) ~orlJl~ of p~r~ yor~ (12) and (1~) ~nd tho w~b~
(16), (18), ~a~) ~nd (22) conn~tln~ them. Al~ho~gh : we~d double ~h~o'c (10) ~ ~llu~tr~ted ln the oml~o~lment, . th- lnv~ntiv~ prlncLpl- m~y o cour~ bo appll~d. to wobbod i multlpl~ ~ho-t-. -.. A~ tha dr~wln5~ ohow, th~ wab~ ~16), (18), ~0) ~.nd (~2) do ~orm no Dlng~.- unit w~th l~y~ 12 ) and t 1~ ) wh-n i ..... , , . ~.. ~ -. - .. ,,.. ,, .. ,, . .. ~. - ;

p~4du~ed ~nde~ conventlonal manuf~ctu~ln~ conatr41nt~, but ~r~ ~ection~llz~d web~, to b- d-~cr~bod ln gr~at~r ~t~ll below, whlch aro remo~bly ~ mbl-d. ~hl~ h~ tho ~dvantage that ~ach l~r (12) or ~14) w~th web ~ectlons (24), (26); ~28), ~3U)~ (3Z), ~34) ~nd ~36) and ~38 extendLn~ th~r-from c~n b~ ~pax~tQly produc~d. ~hl~
mpll~ n ~urn, that both th~ outo~ ~nd lnnor ~ur~o~
~40), (4~) ot~ ~44), (46) o~ eAch layor (14) or ~12) ma~
bo ~moothed, ~or ~xampl-~ by c~len~er roll~ ~eo ~l~o Flg.
4) ln ord-r to obtaln ~n optlc~ t~an~p~rent ~urf~c~, ~o ~hat ~ ho~low-cham~r ~hQet (10) c~n b~ ~urnl~h~d whlch optic~lly 1~ q~ly llk- a qlaJ~ plate.

Th~ vArlou~ ~octlon~ of tho wob~, ~o lllu~tr~tod ln tho dr~wlng~, may ha~e ~ v~rloty of g~ometr~ nd wl~h ro~er~nc- to th- w~b~ (18), ~0) and t~) an advant~g- may be obt~ln~d ln that the d~t~nce botw--n the laye~ ~12) ~nd ~1~) a~n bo vArlod~ whlch ~n ~urn m~y h~ve An im~ct on the X vAlue. A~ a con~o~uonc~, tho thlckno~ o th-hO110W-Ch~mb~r ~he~t ( lO) may a1BO ~Q var~-d. ~ -W b 1~ mAde UP OS a ~C~On ~30) W1th ~ ~1r-COna ~h~d ond (~6) And ~ ~cb-~h~ped ~eotlon ~4~) morgLng lnto layer (12). ~he ~nd ~o~t~on (~6) 1~ m~ted wlth a ~oo~etrlcally Ad~uJ~ed ~ce~ (50) o~ ~ectlon (28). The lnn~r g-ometry of ~ectlon ~50) h~ véral oppo~t-ly di~tancod Loa~-ln rea~ ) wl~h matod look-~n pro~c~on~ ~54) o~ the ~nd ~octlon (46). ~h~ X~nge~enS
r-~lts ln ~ locXable change of dl~tanc- ~-t~-n layex~
~12) and (14).

A ~milar geomet~y wlth r~f~ronc- to th- ~r~o nd- lo obtalnod ~n ~ction3 (32) ~nd (34) of w~b ~2~

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V~ .I;J. v~ IJ ~JIIJl ~ ". .~,IJI 1 1 t,~ ll IIU ~ 7 u ~,LLKI~ dl.,s 200~220 i W~b ~16) 1~ m~de up O~ ~octton~ ~2~) ~nt (26), wh~re ~ctlon ~6) hs~ a bead-llk~ r~lnfo~cement ~6) whlch at lea~t ln ~omo ~glon~ urround~d by a cl~W-l~k- ~nd ctlon ~ S~ ) o~ s~ctlon ( 24 ), whlle hollow~ch~ h-~t ( 10 ) i~ belng as~embled .

Xt 1~ na~u~ ha~ the web~ (16), ~ 20) ~ th~
~ot~on~ ~24)~ ~2~ 2~ 0) and ~32), (34) formlng ~uch webs ~hould o~tent p~pondloular to ~h~ drawlng plane and ov~ th~ entlre wldth or l-nqth o~ lAyer~ ( 12 ) ~nd ~14) .

WhLl- th~ ~ctlon~ of web~ ~16), ~lB) and (20) a~e d~L~o~en~ly llhqp-~ ~o th~t ~ch l~yor (1~) or ~1~) wl~h ~eetlonB oxt-ndlng th~r~rom mu~t b~ made wlth dL~ nt xtru~lon tool~, only a ~lngl- tool L~ neoded ln msklng wob ( 22 ), ~ecau~e the l~yQr~ ( 121 ~nd ( 14 ) w~th tho ~ ~-a~lon~ ~36) ~nd (~) oxtondln~ th~ro~ro~ aro of 3 ld~ntlo~l d-~gn. In o~d-r to connoot the ~ectlon~ (3B) i and ~38), anothor cyllnder-~hA~d ~eatLon (60) 1~ ~o~lde4 whlch 19 lockabl- ~nd lnter~ct~ Wlth the ~nd r-glon~ (6~) ~nd (64) o~ ~ootlon~ ~34) And (3a). ~hl~ o ha~ th-I ~d~n~ th~t the d~t~nco botwo-n layor~ ~12) ~nd (14) can e~lly be ch~ng~d. -~
~.
Flg. 2 ~llu~t~at~ ~ not~blo ombodlm-nt o~ ~n lnv-ntlve W~bb~d doublo ~heot con~S~ng o~ two layer~ ~emo~bly conneated ~y a wob ~6~) ~ F~o~ the oppo~lt~ cf~ce- (731 snd (74) o~ tho l~yo~ ~70) ~nd ~72) p~rAllol, lln-~r pro~ect~Dn4 (76) ~n~ ~70), wh~ch, Y1~wcd ~eat~on~lly, ~ro IcnolP-ltko, mAy ~t~ conn-c~d through wQb-l~lce connector oloment~ ~0); ~l~w~ Otlo~lly~ tho w~ o oonnooto~
elomont~ ~o) ~ro R-~h~ped, ~rhoreln th~ end ~-atlonc hAYo il , .. /V. ~ J Vl~l L.VlV~ . .J(~UI I I ' ~ U ' ' ' ~ ,LI:hh lal~l4 ^ 20092~0 goo~-try ~uch th~t ~h- b~4d~ nd a~ct~on~ o~
pro~ctlon4 ~76) ond ~78) may be r~celv~d ~n a w-y ~lmll~r to locklnq To do ~o~ tho ~reo ~nd~ Or the le~ o~
connoator ol~mont~ ~80) ~oy ~tand ln op~o~lte ar~nge~en~

~n order to mak~ ~ur~ th~t, ~n u~lng tho w~bbed doublo ~heet ~66), th~ w~b-~hap~ conn-ctor l-m-nt~ (~0) do not produce a relatLvo mov~ment loadLng to un~4-ant noL~o~, tho w~ hap~d connoctor plece (~0) ~nd th- pro~ect~on~
(7~) ~nd ~7~) ~r~ lntimatQly connoct~d ~oLntwl~o ~h~
lnt~mat~ ~onnoctlon L~ ch-matlcally ~llu~4to~ In Flg 2 by ~ ~ull-olzed do~ refer~naQd ~y num-~l t8~) -Th b~Lc concept o~ th~ ~ebb~d ~h~t ~CC) Ll~u~trat-d Ln Flg 2 natur411y permlt~ th~ bulLdlng o~ a wo~od muLtL~lo ~ho~t. Th~ s~m~ly ~qu~s~s th~t lom~nt~ ~xt~nd ~o~ ~h~
two ~urface~ e~ the lnner layer~ Thl~ 1~ lllu~tr~tod ~n th~ d~wlno In that, both ~rom ~urfac~ 172) and ~rom tho o~po~lt- ~ur~aco ro~r~ncod ~), pro~ectlon~ t16) ~nd pro~octlon~ ~86) ~nd ~) oxtond, tho latter two ln da~h-d lln-r, ln ordor to ~ t ~ oonn-atlon th~ouqh ~urther web-llk~ conn-cto~ pl-c~ to pro~-ctlon~ ot urth-r l~yo~

A4 lay-~ 17~ 70), ldontlo~lly d~lgn-d, ar- remo~bly con~ted through th~ w~b-lLk~ conn-cto~ ~L~oo~, the di~t~nc- b-twoon lay-r- ~0) ~nd (72) may bc var~ed, ~h~t 1~, by m~klng the d~otanc- ln th- cont~al ~-ctlon o~ th-webbed dou~lo ~h~t gr~tor th~n tn tho ond ro~lon~ ~hl~
v~rl~nt 1~ ~oho~atloally ~llu~trate~ ln ~19 3 Tt 1~
o~vlou~ that th- c-ntral conn-ct~ng w-~ t90) 1~ long-r than the connoct~ng w-bc (92) ~nd (94) ~n th- n~ ~ gl~n-.
~hl~ ~04~1t- ln a bulqlng o~ th~ c-ntral portlon o~ th--`~ 2009220 webbed doublo l~heet ~here)~J~ th~ carrylnq cllp~lt~r o~ the webbed doubl~ ~tleet ~ reu~. Slm~ltAnou~ly, ~he dl~tance m~y ~Q lncrea~ed to auppo~t the webbe4 double 6hee~. ~or exampl~, the dl~t~nce between the l~teral oUpport~ may be 150 cm, wl~h A dlst~nce o~ the l~er~ ln the cen~-ral reglon Of 10 cm and ln the end r~glon~ Or 2 cm.

A6 the lnven~lve w~abbed double or mult~pl~ ~heets con~
oL ~epart~tely p~oduced and ~ubHequentl~ soml~lod l~yers, the decl41ve ~ n~Age ~s that both ~U~f~C~ each layer m~y be smoothed, ~o th~t the hollow-cllamber ~h~et h~ ~n optlcal yuallty èqual to tbat of glas~.

~h0 6urface~ p~o~lded wl~h pro~otlon~ m~y be smoothed by ~nown calQndQ~ roll~ ~96) ~h~ch ln the ~eq~on of the p~o~ec~tl~ns have reces~e~ llk~ clrcul~r grooves (98), malclng ~ure ~ch~t the ~oll ln dolng lts ~moothlng work ls not hlndQred by the pro~ectlon~. 'rhl~ lS ~chem~tlcally lllu~trated ln Flg. ~.

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Claims (11)

1. Multi-layered hollow-chamber sheet (10) made of thermoplastic material, comprising parallel layers (12, 24) removably assembled through webs (16, 18, 20, 22), c h a r c t e r i z e d i n t h a t each layer (12, 24) is smoothed on both sides, wherein from at least one surface of each layer elements extend through which the layers used in making the hollow-chamber sheet are directly or indirectly connected.

2. Hollow-chamber sheet as defined in claim 1, c h a r a c t e r i z e d i n t h a t the layers are removably connected through the elements forming the webs.

3. Hollow-chamber sheet as defined in claim 1, c h a r a c t e r i z e d i n t h a t the layers upon assembly are rigidly connected.

4. Hollow-chamber sheet as defined in claim 1, c h a r a c t e r i z e d i n t h a t the elements are linearly extending projections (26, 30, 34, 36, 38) which may be connected through web-like connector elements (60).

5. Hollow-chamber sheet as defined in claim 4, c h a r a c t e r i z e d i n t h a t the web-like connector elements (60), viewed sectionally, are H-shaped.

6. Hollow-chamber sheet as defined in claim 1, c h a r a c t e r i z e d i n t h a t the webs, at least in part, consist of a material different from that of the layers.

7. Hollow-chamber sheet as defined in claim 1, c h a r a c t e r i z e d i n t h a t when the layers have been connected, the elements extending therefrom are connected to each other, or the elements, through ultrasound or high frequency, are at least pointwise intimately connected with the web-shaped connector elements.

8. Hollow-chamber sheet as defined in claim 4, c h a r a c t e r i z e d i n t h a t the free end (56) of projection (26) is bead-shaped, wherein the bead-like end is mated with a corresponding recess in the H-shaped and web-like connector element.

9. Hollow-chamber sheet as defined in claim 1, c h a r a c t e r i z e d i n t h a t the layers of the hollow-chamber sheet have a distance that is greater in their central region than in their end regions.

10. Method of producing a multi-layered hollow-chamber sheet, wherein the layers are assembled by means of webs, c h a r a c t e r i z e d i n t h a t each surface of a layer is smoothed prior to assembly to another layer.

11. Hollow-chamber sheet as defined in claim 10, c h a r a c t e r i z e d i n t h a t the layer-connecting elements, upon assembly of the layers, are at least pointwise welded or bonded.