CA2178653A1 - Large-area washer - Google Patents

Abstract

In a large-area washer (1) there is an aperture for the insertion of a fastener and a bead (16) to stiffen the washer (1). To pro-vide better engagement with a plate and/or web to be fastened there are engagement compo-nents (13) on the underside of the washer (1) which are pressed out of the whole material of the washer (1) and project approximately per-pendicularly downwards from it. The engage-ment components (13) are conical or truncated cones.

Description

~17~53 .;i3 LAI~GE-AREA WASIIE~
The inv~ntiOn relates to a large-area washer wlth all optnlog ~`or msenirlt~ a fastener, whlch has protruding meshing elements at the surface pointing in the fas~ening direction, which elements increase the ~riction or meshing wlt~l a panel andfot sheet to be fastel~ed.
Such a wasller, ~ lcll Is knvw-l ~rom tlle European patellt application EP 02 83184 ~ I has, on its undersjde, as rneshing eiements, mvlded pms thHt are conlcally polnted ll) anoth~r k~swn largs-area wash~r, mcslllllg ~lemcn~s are provided that are ernbodied IS
conica~ points, which are also produced in ~v,~ ;un ~ith tlle I IfS~ J~e of the washer (US patent 4,9~7,114). In h~th cases, relatively thick plastic wash~rs ~re at issue. ~le provlSi~n of o~her forms of rneshin~ elements o~l ~lle underslde o~` such plastlc wash~rs which, howeve~, may be produced only by an inJectlorl-molding p~nces~, )5 81s0 known ~US p~ttent 5,069t589) rn the case uf one known lar~e-area met~l washer, such meshing elements are formed of brackets stam,oed I~Ut rtf th.' wllole m~t~r~a~ of th~ ~shcr ~nd pressed dow~lwa~
such that those brackets, in frontal view, are emhodicd irl each cas~ trian~ular shape and are oriented with a downward point ~U~ p~tent 4,703,456) The triangular brackets do grip relatively wcll into Insulation or roofing sh~ets, whicl~ sre to be fastened. However, a serious d;s~ ,~ is pres~nted by the fact that tl1e brackets, whicl~ are bent downwald, constitute kl~i~è bla~les of a sort when the cu.~ ,u..d;,~g forces act upoll the roofin~ sheet, thus destroyin~ the roof~ng sheet. ~s soon as no more than a very small cut is produced in the roofing ~heet. no gleat tensile forces are required any longer to pull the roofing sheet out from under the washer Such tensile forces ol~ the ~oofing sl~ee~ oRen result from the effects of the wiDd,p.l;c~ in~hcci~se:~n~tr~ors Washers having a larg¢ area are usually used on a solid underlying stmcture tofasten sin~le layer or mulli-layered roofing 6heets alld~or nn insulation layer. The forces arismg bctwson the roofing slleot artd tlle ullderside of thc washers are relatlvely hlgh and result, in particular~ when the danger exists tl~at the roorlng sheet ..,.d..,.~l. the ~'astel~er or u~lder the washer will be pulled rJut due to ~.".,"~,..d.l~g suction stresses. T~2is tensile strcss on the roofing she~t occurs transverse to the axis of tlle screw, ~hat Is, parallel to ll~e p~ane of t~ie large-ar~a washer. T~e re~entivc force of downward bent, bl3de-likc br.ackets is ~oo slight, so that ~he roofin~ sheet, which is~ in each cas~, altaçilcd in t~lo are~ of the edge, is ~orn out u~ .,.c~.;l. the washer.
A largc-~re~ washer, which Is illtended to extend beyond tlle con~acting ed8es of two s~aling coating sheets is alrcady known ~OE-A-29 30 993) rhe two end re6ions of .is wash~r havc, in each case, a throu~h hole, at the edges of w~llch gripping teeth tllat constitllte grippin~ organs are ennbodled In thls instance, relatively large ho~es dre stamped out, such that the ed~e ar-~s ~f thes~ holes are bent down~vard as indivldual pointed brackcts.
Such an ,"~l~o~:" ~1 would also llot lend itself well to absorbing ~,v~ ul~d;~ large sucsion t`orces acting vn t~le r~ofing sheet, due to thc fact that the grlppillg teesh grip into th~ roofing sheet with atl i..à..l'r~ dcgree of st~ength or, If they d~
en~age prop~rly, t`unction onc~ a~aill as blade~, w~l~ch caus~ a separation of the sheet in ~esponse to tensions para~l~l to the plane of the washer.
It is th~refore an object of the present invention to crcate a large-area washer vf the tvpe mentioned at the outs~t, which provides cm optlmal holding of thc panel and/or sheet to be attached, without the risk that the pallel or sheet will be cut by an d~lu~ t~ force.
Pursuant tv the inven~ion, t~lis objective is .~ c~ owin~ to the fact that ~ever~ yoin~edmesl~ lemenr;, ~r ~e~f~o Ih~rOII m~ l r~he ash--an ^~n~ed ~ 2178~3 l~tt dp~ perpendicularly to tlle plane of the wasl~er, 2re provlded, whlcll are connected at least across a partia~ area of' ~lleir lengtll as ~ .,..f~ r closed cr~nicai ~odies, trullcated conical bodles, pyrantid31, truncated pyran~ita~, cylindrical, or prismatic bodies By these means, as is otherwise CustOmary only in tlle case of plastic washtrs, downward orient~d, pointed m~slling elements are created, wllich b- irlg ~bout a good meshin~
with the roofing sheet or a panel that is to be secured, yet prevent or do not promote, a cuKing uy of th~ r~ofing sheet. Due to the inventive measure, tlle possibility exists tl~aî the washer, with Its me~ elements, can mesh wlth a toofil~ sheet, without cuttlng any f''lber ~;..rv~u~ that may be present In ~he roofing sheet The meshing elententsl of particula m,UllS~I U~.~10(1, pressed from the ~`ull Illaterlal oftl~e washer, do not reslllt In cutting edges of any kil-d, wllich could dalna~e a she~t.
A p~tentirll, particular ~".b~ t resides In the fact that the meshing elements are cu,,~l.u~.tel in tlle form of cup-like depressions pressed from the full material of the washcr 'rhrou~ . FU~ ;u l with ;tn ..pt,l.",.~r~.~ t, ~ , tool, by deep drawing at the tetir~d si~es of thc Irlr~c-~c~ washers, ~1 applu~ ul~lb~r of mesllin~ elements can be produc~d, while th~ formation of cutting ed~es is entirely precluded as a result of tlle ".."f~ lly closed conical, truncated conical, pyrarllldal, truncated pyramidal, cy~indrical, or plismatic form Thus. even when larf~e-area metal washers are used, it is possible to create, in a particular mann~r, an eftèctive meshing elemellt, without the darlg~r of cutting the roofing sheet under load.
It iS entirely possible that the free ends of the meshing elernents, that is, the areas of their points break up slig~ly, even as the meslling elements are .,. r.. ~
However, such a construction call oe brou~llt about ll~ u'~, if th~ meshing elements 2 1 ~
~e, at their free end, an axial diaineter, which is relativeiy small in relation to the diameter at their foot. By ~ese means, a COIl~S~ or a sllarp-edged re~ion, wllich increi~seS the friction relative to the panel and/or tlle sheet that is to be fas~en~d, and also, an impro~ed meshing Wit~l the parlel or the sheet res-llts psrtlculiirly in the rei~ion of the meshin~
~lements. Ne~ hel~ , an ~ff~ctive cuttini~ edge parallel to tlle ipla~te of the washer is not created.
In the cas~ of 0 differ~nt ~ ~ ,5.1; . ~ ~, it is proposed Ihas the wall thlckness of thc meshin~ ~lement decrease collsta~ltly fronn the foot to ~he freeiy l1rotrudin~ end. S~lch a variation exists particularly when th~ solid materi31 is pressed t~lrough w~tll an ~,y,v~
co~inter mold imd a pressing die. This llas i~i addltional positive side eff~ct in thaî the meshing ~Iements b~come soriiewhat ~l-ore elastic ~1l the direction of tlleil free end and, as a result can absorb large forces more easily.
In this regard, it i5 adv~intilgeous if, in ~llc c3se of 3 conical meshilIg element, the out~r conical angle is 50 to 90 alld preteiably 65= to 80 alld the inner conical 3n~1e is 30 to 50 and preferably ~5 to 45. Precisely this particular mAgnitude of the conical itngle bIings about an optirnal meshing wlth the roofing slleet or panel to be secur~d, s~lch thnt a cutting e~ect llc~ h~ a being precludcd Similar angles can also be provided for a pyramidal meshin~, ~lement.
Examples of the invention are explained ill greater det3il ill the following by means of the drawings, in which ~ 21 78653 ~ure I shows a section though an e~cample of a lar~e-area w~sher in ~ wltl fastening layers of insulation and roofing sheet;
Figure 2 shows the sarne example ~s Fiæure 1, however, ~ ts~ la forces ate actin~
on the rooflng sheet, Figure 3 shows a plan view of a washer from above;
FiguIe 4 shows a section alon~ ~he line IV-IV in Figure 3, Fig~lrc S shows a section alon the lit1e V-V in Fi~.ure 3:
Fig~lres fi to 9 show difl'ercnt ~"~I,v,.' t~ of meshing elements in th~ It~ lvll of section A in Figure 4 on an enl~at6ed scale A large-arca washer I is uscd to fast~ll an InsIllatiotl layer 2 and a roofing sheet 3, covering this, on a solid substructure 4. A fastel~er 6, which in thls case is Col~s~ t~ as a screw, is introduc~d into the opelllng 5. The roof~n~ sheet 3 i5 fastencd at the edge region 7, the ed8e region 8 of the s~lbsequent roofing sl-eet 3' coverin~ tlle screwing sites. The roofing sheets 3 and 3' ate then glued or welded to~ether in the region 9 Tlle fastelling itself, is thus placed in a tegion, which is sealed off from the outside.
If now, as can be inferred fronl Fi~ure 2, the roofin slleets 3, 3.' are pulled up by suction forces acting in the direc~ion of arrow 10, then co"~t~ forces act on the screwed connec~ion and t ~ u Iy ~n the washer I The region of the w~sher I, on the right hand side in ~he ~i~ure, is pulled upward ill ~he direc~ion of atrow I I, whereas, the region of t~le washer I in the 1eft hand slde of the drawln~ is pushed downwatd, in the direction of anowl2 ~his ~ 1e3i o~heloo~ind-llerd31sllowl~beheldse~u-el~undellhew~ tl . . 21 7~3 I in the case of such an extreme attack of forces. For this p~lrpose, a special ~ ~ 6~ ,4l and construction of the meshing ~lements i3, proYided at the und~rside of the washer 1, 1S
rcr~uired and will be explained in ~reater dctail below by means of Figur~s 3 tv 8 In the . :'. ' shown in Figure 3 in p~n view, Ihe washer I is c~"lsl.uc~ed as a elon~ated rectangle. Of course, sr~uNe washers or wasllers with a dit~erent exterior shape, such as that of an ellipse can also be used in the surne way. The ~entral opening 5, for inserting the fastener 6 is, u~ l in a depression 14 of the vvastler I, the head 15 of the fast~ner 6 can be di~pused in .~ ~u..6 fnshion dlle trJ thls depression ~4. A periph~r~l bead 16, serves ~o stlffen tlle uasher so that a CUII~!JV~ riontaCtillg pressure can be exerted over a lar~
~rface The course or the ~In~ of such a bead 16, or several such beads, can be ~C~U~ 1 in various ways, which have no significant relationshlp with the meshingelements 13. Figures 3 and 4 show dv~ c.dl~ bent brackets 17, the purpose of which is to hold washers, whlch are stacked on top of one ano~ller at an ~p~..vp~ ~ distance, so that the stacked washers can be sin~ied in a simple m~ er.
What matterl in the case of such lar~e-area washers is how the t;ictlon of r~ltually contacting surfaces of ~he washer and of the panel and/or sheet to be fastened car~ be increased and how a mesllillg with a panel andlor sheet to be fastened can be Improved In the case of the washer describcd here, special mesl~inp elements 13 are provided. Thes~
meshin~ elcments 13 are pressed out from the full material of the washer 1, so ~hat pointed, meshing e~ements 13, aligned at least ~,1,l,,. '~ to the plane of washer 1, are formed.
The most important measure lies thcrein that the meshlng elements 13 are Coll~l u~d, at least over a portion oF th~ir l~n~th, as t,~,. "~ lly closed conical, trunca~ed conical, pyramidal, truncated pyramidal, or prismatic bodies. In other words, an essentially triangular bracket is not just simply bent downward to form the meshing element, as was customary up to now, instead, an meshing element 13 is created, which has a c u~l~v.. and action slmllar to that Or~ fillly c~s~ o~ injeo~ion- old~d ~ni ~I poin ~1 7~653 As may be inferred, for exan1pler from Fi~ure 9, Ih~ m~shing elements 13, are .,u..~ tul from cup-like d~ , which have b~n presscd through from the full materinl ûf the washer I In sl~ch 8 stamping proc~ss, ~ utJ~ counter-tools are available for bein~, uble to achieve such an outwardly clos~d fo~m afler a deep drawin~ process In most cases, it msYes sense if the meshin6 elements 13 have at their free e~d a relatiYely small axial ûpening 19, which is, u.l~d pd~lh,ula~l~ small in relation to thc diarneter at the foot of meshin~ elements ~ ~ Especially when ~he meshin~ elements 13 are produced by deep drawing process, it is ~dv...~t..oc~3 to provide dtJt~lv~JIidt~ angles matched to a particulr~r effect of the meshmg elements 13 in relation to tlle rooting shect tll3t is to be l~old By these means, it is also achieved that the wall Lhickness S of th~ meshing element decreases steadily from the foot to tl~e freely protrl~dln8 end and tha~ the free~y protruding ends of the m~shlng elements 13 ar~ some-vhat mor~ yieldinf~ t~lan tl2e legions i ' 'y at the ~ot of the meshing elernents 1~ For ~xample, the inner conical angle Wl is ",. u '~ 40 for the two . .~ of Fi~ re~ 7 and 8. l't~e outer conical angle W~
iS ~t~t~ 70 for the . 1- ~ of Fil urc 7 and ayl/.u,~..,.~t~l~ 75 for the m~ t of Figure 8 Adv~snbly, the inner conical angle W I is of the ord~r of 30 to 50 pre~crably 35 to 4S and tlle o~lter conical angle W2 is of the order of 50 lo 90~ and preferably of 65 to 8v For the co..~llu~l,v.~ of Figure 6, thc w~ll thickness S is practically constantovrr t~le whole len~th, with tl~e e.Yception of the direct fr~e end of the meshing element 13 The production of such a Yariation by a stampin~ process is also ~ul~ce;~dbl~, in which c~se, the free end region of ~he meshin~2, elements 13 so ~ormed burst open slightly, 50 thnt a ~h ~, or cv.,.~uv.,d.n~, cracks, which increase the t`riction, are formed or form st the &ee end of ~he meshin~ elements 13 In the case of the ~ v ' of Figure 8, it can be ~ecn ~h~ ~ w~ ul~ A o~ ~olh~d llmilina ~1:~. which in mlll ers~lres spcci~ ic~ion-2 ~ 78~S~
creasing effect when used in the roofin~ slleet, is ~ormed at ~he free eno of the meshlngelement From the geometry alone, it can be s~en that lhe ~u~ u~llùl~ of such quite spcc~al meshing elen~ents 1~ can be u~ced not only for large-area washers made t;om me~sl.
but alsû for washers produced from plaslic br irlJection nnoldlng In the case of Ihe c ' ' shown itl ~ ures 6 to g, the nteshin~ ~lemel~ls 13 are ~.,.;, ' _1!~ closed prsctically over their whole lel~gth It ~ould 31so be cûa.."~dl,l~ to ConstruCI only tlt~ foot region of the meshing elements p~.i,' "~, c~osed, the remaining region up to the fre~ end bcing dlYided up In~entlonally or due to the .t~3...,~,...Q~ts of the material inlo individual brackets. which ~on~inue to ~'orm a I)~ C ~ closed total form, wltl) lhe e.YCeptiOn of the narrow slots ~ying in between It would also be ~o~ iv~lc to provide slots or tears in the foot re~ion of the meshlll~3 e~ments, thnt is, m th~ tlan~ition region from t~le planar section of the washer to the slots or cracks .iu.~ ù..cii..b to the meshing element, which then cvlltribute practically at the outer wall of the meshing elements 13 to an increase in frictioll relative to the s~leet to be fastened Even thou~h ~u"~
cracks or slots would then be present, no cutting edge-~ike cu~ u~l;vll~ would lesult al the mes~tillgelements 13 In order to mal~e 8~od penetration of the meshtn~ elements into the panel and/or sheet to be fastened posslble, m~shing elements 13 ad~ are constructed, which consist of a Ui~l r ~ ' ~Iy closed conical, truncated conical, pyrarnid~l. or trunc~ted pyramjdal body It is, however, also pvssible to construct the meshing elements in the form of a cylindrical or prismatic body, in which c~se, however. the penetration behavior into the p~tnel ~nd/or sheet to be fastened woul~ b~ inferior Ht)we~er, ~specialiy due to the special ..~I;v.. at the free end of such a meshing elem~nt, tl~ere can be a si~nificant increase in friction. which, in tum, makes possibie a particularly eff~ctive lrlrge-area washer

Claims (5)

Claims

1. A large-area washer with an opening for inserting a fastener, which has protruding meshing elements at the surface pointing in the fastening direction, which elements increase the friction or meshing with a panel and/or sheet to be fastened, several pointed meshing elements (13), being oriented at least approximately perpendicular by the plane of the washer (1), characterized in that said several pointed meshing elements are pressed from the ful material of the washer (1) and which are connected at least across a partial area of their length as circumferentially closed conical bodies, truncated conical bodies, pyramidal, truncated pyramidal, cylindrical, or prismatic bodies.

2. The washer of claim 1, characterized in that the meshing elements (13) are constructed in the form of cup-like depressions (18) indented in the full material of the washer.

3. The washer of claims 1 or 2, characterized in that the meshing elements (13) have at the foot of their free end an axial hole (19), which is small relative to the diameter at the foot.

4. The washer of one of the claims 1 to 3, characterized in that the wall thickness (S) of the meshing elements (13) decreases steadily from the footup to the freely protruding end.

5. The washer of claim 4, characterized in that, the outer conical angle (W2) of the meshing element (13) is 50° to 90° and preferably 65° to 80°
and the inner conical angle (W1) is 30° to 50° and preferably 35° to 45°.