CA1249109A - Roughened cleaning sponge particularly for delicate surfaces, and manufacturing method therefor - Google Patents

Abstract

ABSTRACT

A roughened cleaning sponge, particularly for easily scratched surfaces, such as stainless steel surfaces, surfaces coated with thin layers of a plastic materials motor vehicle windshields, and the like, which comprises a core of a sponge-like material covered with an outer roughening fabric. Both the core of sponge-like material and the roughening fabric, the latter being a knit tubing, are formed from a thermoplastic plastics. The crosswise seams are pressure heat sealed to define a stiff heat sealed band having scraping side and corner portions.
A reliable and durable envelope is thus provided for the sponge-like core. Manufacturing begins with the formation of a basic blank of some length from which individual sponges are fabricated by heat sealing and severing along the heat sealed end bands thereof.

Description

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BAO.[Gl~Ul:o 01 r ~ l~NTI ~
Thi~ invention relates to a roughened cleaning ~ponge par-ticularly :EOI~ delicz~e ~urfaces~ and tG
method of manLI:facturing it.
~ he roughened sponge of this in~entio~ i~
particularly useful for cleaning scratch ~ulnerable surfares~ sueh as ths surfaces o~ ~tai~les6 ~teel objects, or objects coated with a thin layer of plastics like cooking pots and pan6~ or motor vehicle windshields~ Such objects, in fact7 ~hile ha~ing inherently hard surfaces, are quite vulnerable to scratching sinc~- this ~ould jeopardize their proper use or operation~
It is a well known fact that scratche~ on stain-less ~teel pot~ ~d pa;~s or no~-adherent plastic ~oatings, addition~ to marring their appearanGe may encourage ~ood sticking during the oooking process, while in the instance of a windshield, any æcratches are liable to in~er~re with a clear Yie~y especially whe~ drivi~g in the rain or fogO
On the other hana9 such objects do require periodic cleaning7 ana occa6ionPlly al50 removal o~
~ard or stuck depo~itæO
~ or ~ueh cleaning purposes as specified abo~e~
either ~elt-like rags are currently utiliæed or ~ponges incorporating scraping fillers, eOg. diamond powders, as we~l as roughened sponges including a core o~ a sponge-like material and a roughening ou~er cover ~or ki~chen application~9 and those same a~rasi~e filled ~ponge~ and known hard rubber scraper6 i~

:IZ3L~9 for winashield cleaning applications.
It has been found in actual practice that prior sponge~ including abrasive fillers may indeed originate much feared ~cratche~, whereas elt type rag~ may lack fretting ability and above allg owing to their substantially two-dimensio~al nature, do not lend themselve~ to the application o~ a large $1at surface again~t the object to be cleaned. Such rag~ are9 in fact~ held rolled up in one hand, ~o that the sur~aoe to be cleaned i9 o~ly eng~ged in practice ~y the crests of the individual folds thus formed in the rag~
Another di~advantage of such rags, as well as of prior abrasive filled sponges9 i9 that they can present no ~tiff side or corner edge~ ~hus, they cannot be useful to carefully clean, ~or example, the peripheral corner~ o~ pot ~nd pan bottoms, and any other areas having corner~, ridged or rece~ses9 ~uch a8 the handle~
of pots and the like eooking utensil~. Nor are kno~n ~crapers in the form of hard rubber blades9 ~or cleani~g wi~dshield~, de~oid o~ problem~. ~he same, i~ fact, where provided as individual cleaning tools both for ~craping purposes and for wiping a~ay wa~hi~g ~a~er from a windæhield9 and form, therefore~
primarily scraping and not cleaning tools, aB against 6ponges, rags, and the like. Not even the sponge strip ~ometimes assoeiated with the same ca~ provide accurate cleaning9 because the spo~ge strip i~
supported, like the ha~d rubbsr blade, in a rigid ~trip like ~tructure lnhich car~ot accommodate the wind~hield crown:ing. :Further~ t~e pro~i~ion of a ~ Q ~

handle on ~uch scrapers makes them unwieldy~
The cited pri.or ~ponge~ including a roughened eovering are essentially of two types. ~ first sponge type comprises a core formed from a non-thermoplastic foamed material and a fabric portio~, also formed from non-thermoplastic materi~ls, whioh is wrapped and ~ewn around the core. This construction has the disadvantage o~ invol~ing manual processing and being time con~uming. The roughened ~ponges of the ~econd type comprise a sponge-like core of a non-thermoplastic materi~ and a fabric covering of a thermoplastic material. The fabric i~ here in the form of a tubing. l~a~ufacture provide~ for manual introduction of the ~ponge like insert into its outer sheath and sealing of it~ ends. ~he sealing i practically o~ a li~ear type ~d of ~omewhat limite~ ~trength oning to ~he ~mall amou~ of thermo-plastic material available for the p~rpose~ in practice just that provided by *he yarns cf the roughening fahric. In addition to being ~lo~ to manufacture 9 such prior sponge~ tend in use to open up a~ ~he ~ealed end~ whi~h are constantly under stress ~rom the spo~ge core tenai~g to expana.
~ s mentioned abo~e~ such prior ~ponges with outer rougheni~g ~a~rics lack any stiff side or corner edge~
S~MMARY O TEE I~VEN~IO~
It i~ a primary object o~ thi~ invention to proYide a roughen~d cleaning sponge9 ~hich can retain unaltered its original shape9 eYen after ~z~

prolonged use, and incorporate3 a scrapi:ng mea:lls of it s owrl~, Another ob; ect of this invention is to pro~ide a method of ma~ufacturing sponges according to the invention, which can a~`ord a fast BpOnge production rate without waste, the sponges obtained with thi~
method requiring no f~rther processi~g Isr fini~hi~g ~tep~
Starting from a cleaning spo~ge of the general type outli~ed hereinabo~e and comprising a core o~
a sponge-like material which iæ covered e~ternally with a roughening fabric coveri~g, the obj ect~ of this invention are achieved by that the inventive spollge has the following characteristics:
a) the sporlge-like material core comprises a thermoplastic plastics;
b) the rougheni~g fabric covering ~lso comprises a thermoplastic plastics9 lthe fabric coveri~g blank being provided in tubular form;
c) the cro~swise closures are obtai~ed bg heat sealing in the ~orm of a J3trip-lil{e b~a; a~d - d) the heat ~ea:Led end ~trip-like ba~d~ ha~re their respective front ~3ide ana outwa:ra corners ~tifflg shaped.
QLccsrding to the invention9 the fabric tubing i~ a }mit ~abri~, that i8 having a ~mooth weft and ~Narp garns projecting therefro~ into loop~ o~ a gi~erL
len~sth a~d orll~ protruding from one ~ide with respect to the weft ~ a portion oiE the loop~ being cut o:E~
to provide two respective scraping pile~30 Said cut .. . .. .. ....
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of~ portions of the loops amounting approximately to 40~ o~ the total loop numberO
~ urthermore~ according to the inve~tion, the projecti~g l.oop~ are arranged to protrude inwardly of the tubular fabric blankO
A1SQ according to this inventiong the heat sealed end bands or ~trip~ have a cro~swise dimension in the ra~ge from about ? to 10 mm.~ this sealing providing for a oompacting sealing applica~ion of compression under heat to both the thermoplastic material. of the roughening fabric and thermoplastic material of the sponge~like core.
~ dvantageousl~ the ~idth of ~aid heat sealed strips ~ould be about 7 mm. ~ccording to a further aspect of the in~ention, the outer edge~ of the heat ~ealed ætrip Btand o~t of the roughe~ed aponge-longitudi~al eide~, in the fi ~ shed conaition of the sponge, th~æ affording ~ull acce~ a~ility to the remotest o~ the area~ or corner~ to be clea~edO
I:~ actual practice7 good re~ult~ ha~e been achieved b~r UsiIlg a sponge core ~d roughening fabric which re~lt in a heat sealed edge about ~ mm thicko The method of this i~vention" for the ma~mfacture of roughe~ed ~leaning spo~ge~ accorai~g to other aspect~ of the invention, distinguishe~; itself by the use of a ~ponge~ e thermoplastic plastics core as an elonga-te secti onal blank and of a tubular rough-enillg :~abric coverirlg with inwardly projectin,g loops~
and is characterissed ~ th~Lt it compri~es the ~ollo~qing processi~g ~;teps:

- 7 ~ ~L2~L~3~ 3 ~ ) i~sertio~ of the roughening Eabric through a liniDg tubiDg;
B) turning said tubular fabric i~side out by backfitting ~aid fa~ric over ~aid lining tubi~g sub~tantially for t~e full length thereo;
C) se~ering of the tubular fabric at the opposed end of the lining tubin~ to the end thereof where the tubular fa~ric has been inserted therethrough9 ana with~rawal from within said lining tubing o~ the tubular fabric present therein3 D)introduc~ion through said lining tubing9 and substantially *or the full length thereof9 of a core ~ectional or extruded ~lank formed -from a sponge-like material, and severing of the same to separation;
E) simultaneou~ withdrawal from the lining tubing of both the outer tubular fabric and sponge-like ma~erial core located în~ernally to said lining tubing~ thereby said core i8 positioned wi~hi~ said tu~ular abric with its loop~3 out~rds and a contin~us ~;tarti~g ~lank o~ con~idera~e length, e,.g. five meters long, is Iormea; and :1?) sep~atiorl from said bl~ of individual sponges b~ means o~ a w~de stri~i~e heat sealed ba~a produced lmder t~rust ana compression9 ~ollowed by severing along the ~eat seP:~ ed band midline to separa~e a completed cleaning sponge from said co~ti~uou~3 starting bl a~k.
Furthermore7 according to the in~ention7 on the ha~f-ja~7s of the heat sealing he~a, the heat ~ealing rec~ptacles or impressio~s are such as to form~

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during the heat ~ealing process~ outer end corner edges ~hich protrude from the longitudinal sides of the fini~hed cleaning ~ponge.
In addition to incorporating to the roughened cleaning sponge a scrapi~g means of compact configuration~ ~ivhich means also unctionss, advantage-ously~ as a sealing means fQir the sponge itself 7 an advaIl~age of this i~vention proposal resides in the pro~i~ion of a~ e~ctremely simple and rapid ma~ufacturing procedure which requires no fi~ishiIlg step:~: for the manufactu:red sponges.
As for the number of the opened, or cut off, loopsS excellent result~ have been obtained with a number of cut off loops on the order of 40~ of the loop ~otalO
A further advan~age of the ~ponge~ of this inYention i~ that optimum filling of the roughen ~g fabri~ with the spo~ge core is achieved, which positively ~oids the formation of ~oid pocket~
betwee~ the spnnge a~a covering ~uch a~ ~ould result in u~wanted wri~k~es on the sponge surface in use.
~hi~ solid filli~g of the tubular fabric i~ achieved quite simply a~d easil~ through the use of the cited assembling lining tubing.
~RI~ DE~CRIPTIO~ OF THE DRAWI~GS
~ urther ~eatures9 advantages, and details of the roughened æponge and related manufac~uring method, according to th~ ~nvention~ will be more readily ~der~tood from the follo~iDg description, with re~erence to the accompanying drawings~ which - 9~

illustr~te schematioally a preferred embodiment vf the inventiorl5, a;~d where:
:Figure 1 i~ a per~pec-tive view o 'a roughened cleaning sponge incorporating a scraping me~s 5, according to thiæ inYention;
Figure 2 is a pla~ vlew of the same;
Figure 3 is a ~ide elevation viev~ of the sponge o f Figllre 1;
~ igure 4 i~ a ~ront view of the same;
Fig~e 5 is a sectiorlal view ta;ken along the line V-V in Figllre 3;
:Ei'igure 6 is a sectional view taken through the tubular fabric employed for a roughening fabric;
~ igure 7 is a longitlldinal sec:tion view through a lining tubing or ho3e for slee~ and assembling the ~abric" shown during a fabric sleeving ~tep;
:Figure 8 i9 a ~ectional vie~v ~imilar to Figure 7, wikh the rougheni~g fa~ric ~leevedj Fig~e 9 i8 a :3ectiona~ vie~R ~milar to Figures 7 a~d 8 showing a ~ponge section~l blank introducea through the lini~lg tubi Figure 10 is a similar sectional view take~
thrcugh the ~ining tubing or :hose9, shovlli~g ~ 9tar'ting blank already assembled at the leading portion thereof, Figure 11 i~ a l~ngituainal ~3ection view t~rough the csmple~ed starting blank; and ~ igure 12 i~ a theoreti~al cross-~ec-tional view i11u~tI ating the material displaceme~t during the making OI heat sealed e~d ba~d~.

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DES~RIP~IO~ O~ THE PR~FERRED E~BODIMEN~S
. .
~ king reference to the drawing figures, some o~ which are drawn to different scales~ similar part~
are designated wi~h the same reference characters.
This cleaning sponge is generally indicated at 1 and comprises, in a manner known per ~e~ a core 2 of a sponge-like or e~panded material ? and an outer fabric covering wi~h rougheni~g functionæg indicated at 3.
According to the in~ention7 both the sponge core

2 and roughening fabric 3 are formed from a thermo~
plastic plast L,CS~ that iB on~ accepting heat sealing or ultrasonic ~elding. The thermoplastic material, both for the roughening fabric and sponge core~ is selec~ed to ~imultaneously provide for heat sea~ing of the ends and the formation of a scrapi~lg mean~
directiy from the materials utiliæed~ wlthout in~ol~ing a~g insert or supporting elements~
The ~abric employed i9 a tu ~ lar or hose fabric ~ith looped ~arp g2rns, or knit fabric, ~hich loop~, .
in the preferred embodimen~ dicated, are arranged to face inward~ as shown i~ Figure 60 In a preferred ex~mple; polye~ter ~arn has been u~ed for the weft and polypropylene yarn for the warp~ th~ yaxns having a diameter on the order of 0,2 mm, while the loop~ had a height of about 3 mm and a length between the loop legs of about 1 mm. The number of ope~ed~
or eut off~ loops amounted to about 40~ o~ the loop total. The height of the sponge oore was 2.5 mm~
I~ thi~ way, and as explained hereinafter, it ha~

been pos~ible to form a good heat sealed band ~ith ~craper functïon3~ That heat sealed ba~d has a considerable width, e.g. a ~idth of 7 mm~ and a thickness adequate to pro~ide, on the one ~ide~
optimum scraping rigidity, and on the other side9 a favorable flexing ability in use of the sponge~
~ Yith the dimensions specified a~ove, a fa~orable thickness on the order o~ about 1.3 mm and e~d ai~placements of the material are achie~ed, said displacements resulting in the formation of end corner edges or ~lap~ which stand ~lightly proud of the sponge longitudinal ~ide~ as clearly brought V~lt by Fi~lre 2~ ~he heat sealed band i5 indicated at 4, ~nd 4a designates the projecting end corner edges, while 4b designa~es the projecting ~nd flaps and 4e the front scraping side. Owing to the very nature o~ the heat sealing proce~s~ the value speci~ied should be regarded a~ an averæge value beca~e thick-ne~;s devia~ions may, of co~rse, occur along the length of the sealed band 40 ~ he materia~ displacemerlt~ ~vhich result in the fo~mation of ~he coF~er edge~3 4a and flaps 4b, protruding later~lg~ are accomplished forcibly on heat sealing through the use of correspondingly shaped receptacles or impressions in the heat se~l ing 3aws, or alternatively~ by changing the pressure ~alue selected therefor.
~ ccording to the in~en~ion, ~or the manuIacture QI t~e propo~ed ~po~ges" a preassembled blank of a ~on~idera~le le~gth, e . g. 5 m5, is first pro~rided.

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The same i~ prepared u~ng a lining tubing~ indicated at 5~ ~ir~t th~ tubular fabric 3 is inserted there-through~ and then the tubular fabric i~ rever~ed onto the outer ~urface of the lining tubing 59 as shown in ~igure 7. At this point~ the tubular fabric 3 i~
~e~ered at the opposed end 5b of the lining tubing 5 to the inlet end 5a9 and the fabric p~rtion is with dra~n from the interior of the tubing 5. ~hus ? the condition of Figure 8 is established. ~ this poin~t the sponge sectional bla~k 2, in the form of an elongate ~ectional blank, is inserted through the lining tubing 59 as shown in Figure 9, and the same is severed at the end 5a of the tubing. As brought out by the Figure6, the loops of the fabric 3 will now be facing outwards. By grasping with onel 5 hands, at the end-5b~ both the f~bric 3 ~nd initial portio~ o~ the ~ponge aectional blank 2, a pulling force i3 applied to simultaneously withdra~ ~rom the lining tubi~g 5 both the outer fabric 3 ~a inner sponge sectional blank 2, ~ich is automatically positio:ned withi:n said fabric, as sho~ in Figure 10. The ~tarting blank formed by the fa~ric 3 a:~d sponge oore 2 i~ indicated at 6 in Figure 11.
Shown schematically at 7 i~:L Figure 12 are the lines of action of heat sealing jaws for the formation o the sea ed bands 4~ Indicated at 8 a:re the a~eas of fabric material 3 ~d ~ponge material 2. v~hichS, during the heat sealing step" are displaced and compressed into the sealed bands 4. ThP same may be produced either a~ si:~gle or double seams~ or even simultaneously on two ad~acent ~ponges. In the latter case~ the common band~ of double the thicknes6, will be separated by means o~ a blade element or ~he like~
It ma~ be appreciated from the foregoing -that with the teachings of this invention it becomes possible to effectively achie~e the objects thereof~
both in connection with the compo~ite construction sponge and manufacturing method it di~clo~e~.
In practicing the invention, it ~ill be pos~ible to replace the materials speci~ied above ~ith other thermoplastic materials~ s~;ch~ s, f~r the we~t yarn, polyamides, Nylon, A1godo~ polyethylene, polypropyl-ene, raf~ia, and the like, while for the warp yarn, polyethylene, ~ylon~ polyester, Algodon, etc~ mag be used, and de~iatio~s from the specified dimensions ma~ be made without departing ~rom the scope of thi~
in~ention. Sub~tantial ~o the same i~ the incorporation to the sponge with roughe~ed co~ering of ~craping means as ~e~l, ~hlc~ advantageously pro~ide for the sponge sealing. ~11 this ~ithout involving a~y additional ~inishi~g steps.
Heat sealing could be replaced by an ultrasonic or any other ~uitable sealing process.
It is also contemplated, of course, by the in~e~tiGn that sponges may be provided with sealed ban~s haYing diferen~ pro~iles, as indica~ed in ~igures 13~149 or sponges be provided with periph~ral~
~y extending sealed bands~ as shown in ~igure 15~ or wi~h intermediate sealed spots, as shown in ~igure ~ 14 --16, or in the form of a padded element, etc~
The manufacturing method could be Putomated by replacin~ the manual withdrawal of the fabric and sponge core from the lining tubing with ~ome automatic withdrawal procedure7 again without departing frQm the invention scope.
~ 11 of the features that may be inferred from the specification, claims, and drawings are regarded as essential to this i~ve~tion, both indi~idually and in arly desired combination thereof.

Claims (9)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A roughened cleaning sponge particularly for delicate surfaces, comprising a core formed from a sponge-like material covered on the outside by a roughening fabric covering, and characterized in that:
a) the sponge-like material core comprises a thermoplastic plastics;
b) the roughening fabric covering also comprises a thermoplastic plastics, said fabric having a tubular configuration; and c) the heat sealed strip-like end bands have their respective front side and two outward corners stiffly shaped and adapted to act as scraping means.

2. A roughened cleaning sponge according to Claim 1, characterized in that said fabric is a knit fabric, that is formed with a smooth weft wherefrom warp yarns stand out with loops of a given lenght only protruding from one side of the weft, some of said loops being cut off to form each two scraping piles, said cut off loops amounting to about 40% of the loop total.

3. A roughened cleaning sponge according to Claim 1, characterized in that said heat sealed end strips have a crosswise dimension in the 2 to 10 mm range, in the course of the beat sealing process, a displacing compression and compaction being applied to the thermoplastic plastics of both said fabric and sponge-like core to form a rigid heat sealed band affording at the same time the required flexibility of application.

4. A roughened cleaning sponge according to Claim 1, characterized in that said heat sealed end bands have a widthwise dimension of about 7 mm.

5. A roughened cleaning sponge according to Claim 1, wherein the outer corner edges or side flaps of the heat sealed bands protrude laterally from the longitudinal sides of the completed sponge.

6. A roughened cleaning sponge according to Claim 1, wherein the thickness dimension of said heat sealed bands is in the order of about 1.3 mm.

7. A method of producing roughened cleaning sponges particularly for scratch vulnerable surfaces as claimed in Claim 1, characterized in that it comprises the following steps:
A) insertion of the roughening fabric through a lining tubing to emergence from the opposite end to the inlet end;
B) turning said tubular fabric inside out by back-fitting said fabric over the outer surface of said assembly lining tubing substantially for the full length thereof;
C) severing of the fabric in the proximity of the opposed end of the lining tubing to the inlet end, and subsequent withdrawal from within said lining tubing of the tubular fabric present therein;
D) introduction through said lining tubing substantially for the full length thereof, of an extruded sectional core of a sponge-like material, and severing of the same to se-paration;
E) simultaneous withdrawal from said lining tubing of both said outer tubular fabric and sponge-like material core from said lining tubing, thereby said core is positioned within said tubular fabric with rougheneing loops now facing outwardly and a continous starting blank of considerable length, e.g. five meters long, is formed;
F) separation from said starting blank of individual composite construction sponges by means of a side strip-like heat sealed band produced under thrust and compression.

8) A method according to Claim 7, wherein during the heat sealing step; a heat sealed band shared by two successive composite sponges is formed, said heat sealed band being then severed by means of a cutting member or the like.

9. A method according to Claim 7, characterized in that, on the half-jaws of the heat sealing head, the heat sealing recesses or impressions, if any, are configured, or the heat sealing pressure set, such as to cause, during the heat sealing step, a displacement of thermoplastic material to form protruding outer end corner edges and end flaps from the longitudinal sides of completed sponges.