CA1249318A - Apparatus for making a molded window gasket assembly - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
An improved window gasket assembly and the apparatus and associated method for reaction injection molding such assemblies, as well as other molded articles, are disclosed. The gasket is preferably integrally molded from an elastomeric material such as urethane onto a substantially transparent window panel. The gasket and window assembly can then be mounted and secured directly to a vehicle body panel opening, for example, with adhesives, thereby eliminating the need for discrete mechanical fasteners. In a preferred embodiment of the invention, an improved aftermixer and gating apparatus includes a mixing body in which a flowable multi-constituent molding material is separated into a number of generally serpentine mixing passageways and reunited in a common mixing cavity before being conveyed through a fan-gate passageway to the mold cavity. Adjustment means is provided for selectively altering the size of the mixing cavity and its inlet openings in order to selectively alter the back-pressure exerted on the material flowing therethrough, thereby enhancing the mixing of the molding material constituents. An improved mold apparatus is also preferably employed and includes elongated elastomeric members along the preferable edge of the mold cavity for supportingly engaging the mold members and substantially minimizing or preventing flashing of the molding material therefrom.

Description

lhe inv~ntion rel~es gener~lly to nOldæ ~indow ga6ket6 ~nd to the ~eactlon in~ec*ion Dold~ng of ~uch srtlcles from a ~lti-con6tituent ~aterial in a ~old c~vity. ~Dre p~rticul~rly, the ~nvention rel~tes to such g~çkets sr autorotive applicatlons and to equipment and methods of reaction ~njec~ion ~old~ng of B~Ch article~, wherein the elastomeric wlndow gaskets are integrally n~lded onto o ~indow Eanel of gl~s or other transparent ~ateri~l.
It has been knswn ~n the past to fab~ic~te nrticlefi ~uch a6 ncdul~r windww ga~kets for vehicular in6tallations from materi~l~ 6uch a6 polyvinylchlorlde (PVC~ u6ing conventional compre~sion or injection snolding techniques. Some of 6uch window ga~kets h~ve been lnjection mold~d di~ectly onto the windcw panel, ~h~ch i6 made o~ glass or other 6ub~tantially transparent naterlnl. Ihe w~ndow and gasket assemblies have ~hen been in~talled in a vehicle or other window frame wlth adhesives and/or with integrally molded f~6tener protru~ions, ~8 disclosed, for example, in ~nited States Patent ~08. ~,072,34D and 4,139,234. It ha~
been found, however, that windvw panel breakage has been unacceptably hi~l in 6uch prlor processes because of the hlgh pressu~e5 re~uired in the injection molding pr~ce~ses and becau6e ~f the hardne~s and rigidity o~
~he mold structure6 involved. ~dditionally, becau6e of the type6 of material6 previously used ln molding the gasket6, such a~ subber or polyvinylchlorlde (YVC~, it ha~ been found Lhat proper a~hesion of BUCh gasketE to m~tnl body panel~ and to glass wlndc~ ~anel~ ha~ been difficult

2~ to atta~n, thereby resulting ~n water ~eak6, wind noise, and other related problems, aG well n6 requiring the use of medhanical fa6te~er~ to secure the a~emblie6 to the body pDnels.

~, x~ 3 This applica-tion is a division of commonly owned Canadian Pa-tent AppLication Serial No. 448,329 filed February 277 1984.
In accordance with the present invention, improved apparatuses of reac-tion injection molding articles such as vehicular window gaskets are provided in order to overcome the above-discussed disadvan-tages. Such appara-tus allows window gaskets to be reaction injec-tion molded from multi-constituent liquid materials, such a~
urethane, for example, and to be molded at relatively low pressures directly on-to -the glass or other transparent window panels. The gasket and window panel assemblies can then be mounted directly into a wlndow opening in a body panel and secured thereto with adhe~ives withou-t the need for mechanical fastener devices~ thereby 8implifying the installa-tion process and making i-t be-tter suited for robotic or other automa-ted equipment. All or a portion of the gasket can also be coa-ted wi-th a pigment decorative ma-terial in the mold cavity if desired.
The gaskets as produced by the apparatus of this invention may also be fabrica-ted wi-th a lower cross-sectional profile, thereby providing for a smooth aerodynamically advantageous fit between the window assembly and the body panel. Such lower ~rofile also re(luire~
less offset or other forming of the body panel area surrounding the window opening, thus simplifying the body panel fabrication and increasing the design flexibility for such body panels. Also, because the gaske-t and window assembly is preferably bonded and secured to the body panel substantially con-tinuously around the window opening periphery, the localized stress concentrations caused by spaced, discrete mechanical fasteners are substantially avoided and the bonding LCM:mls ~J~

and securing forces are more evenly distribu-ted. Thig allows the window panel -to effectively contribute to the s-truc-tural integrity of the installation, and also to allow for a recluction in window panel thickness and weight.
In a preferred embodiment of the present invention, an aftermixer appara-tus for use in a reaction in~ectlon molding system includes a mixing l,CM: mls

3~

body having at lea6t one co~mon inlet pa~ageway for receiving a ~ulti-oon~tituent ~aterial in a F~e~r;urized fl~able ~tate. qhe ap~r~tu~
lnclud~fi ~ n~ber of ni~ing pa~age~ay~ ~dapk~ to ~ceive the m~terial from U~e common inlet pas~ageway and separate it into ~ corr~ponding number of raterlal flow ~tream~ A ~ommon mixing cavity ~1 fluid ccnmunicatiun wi~h the ~ixing pa~ageway~ reunlte~ the 6eparated flow 6treæm~ hnd convey~ the material ~nto ~ yating device for introduction lnto the mold cavity. Adju~tment mean6 ls provided for 6electively altering the Bize vf the oommon ~ixing cavity and the size of it~ inlets 1~ ln order to ~electlvely alter the back-pressure e~erted on the ma~erial flowing ~lerethrough. Such ~dju~tment feature ~llows or the nptinlzation of ~.e back-pressure ~nd thus the internlxing of the oonstituent~ of the naterial for ~ given flow rate and inlet pres~ure thereof. Preferably, the mixing pas6ageway6 each extend along a generally ~epentlne path incl~ding at least cne bight portion adapted to cause the n~terial flowing there~lro~gh to sub6tantially rever6e ~ts directi~n of ilc~ in order to increase turbulence and e~)ance the nlxing ~f the material constituent6.
At least a portion of the preferred mold cavity of the reaction injection molding cy6tem includes one or more elongated elastomeric n~mber~ positioned generally adjacent ~he peripheral edge of ~le ld cavity for 6upportingly e~ngaging the mold menber6 and the window panel.
n~e fle~ible elongated elactomeric member~ are preferably seated in grooves in one or the other of the mold n~n~ers and are further adapted to 6ubstantially minimize or prevent fla~ling of the gasket material o~t of the ~old cavity and al60 serve to acca,~date variations in the ~,ape of the win~ow panels.
Additional o~jects, advantage~ ~nd feature~ of ~le present invention will beccme apparent ~om the ~oll~wing description and appended clains, taken in conjunction with the acccn~anying draw1ng~.

3 ~

Figure 1 lllustIate~ ~ portion of rn exemplary v~hlcular window n66e~bly, partially ln cro6s-6ection, having a window ga6ket m~mber lntegrally ~o7ded onto n tranEE~rent ~indcw panel in accordance with the present lnvention.
Figure 2 ic h r~ ematic diagr~m illustr~ting ~ reaction injection ~olding Ey6tem for fabricatLng ~he ga6ket ~nd window panel assen'oly of Figure 1.
~igure 3 1~ a partial cros6-6ectionAl view of a mold a~paratus lo for t-he lding 6yste~ illustrated in Figure 2.
Figure 4 i~ a per~pective view of ~n aftermixer and gating apparatus for a reac~ion injection molding apparatu~ in accordance with ~e present mvention.
Figure 5 i~ ~ cross-sectional view taken along line 5-5 of Figure

4.

P~hEP P~S5RJE~IL~L Q_~E~_PR~F~R~P J~D~2I~3~i In Figure6 1 through 5, exemplary embodiment~ of the present invention are illustrated for the reaction ~njection molding of integrally-molded vehicular windcw panel gaskets onto their a~sociated glass or other transparent ~indow panel~. One skilled in ~le art will readily recognize rom the following di6cus6ion, however, that the prinsiples of the invention are egually applicable to re~ction injection molding of item~ o~)er than vehicular window gaskets, as ~ell ~s being ~L~licable to apparatu6 other Lhan the react~on injectioin molding 6ystem sh~wn in the drawing6.
In ~igure 1, ~ vehicular window assembly 10 generally ~ncludes ~
vehicle body or other panel 12 having n reces~ed portian 14 ~rrounding an opening for reoeiving a sub6t~ti~11y tfan~parent window panel therein.
In the exempl~ry ~indow ~6~emb1y 10 illustr~ted in Figure 1, n tran~parent ~indow panel 16, ~hich i6 prefer~bly gla~6, hn~ a window ga6ket ~e~ber 18 integrally molded ~herecn, with an edge porti~n 17 of the ~induw panel ~ub6tantially ~mbedded ~n the ga6ket member 18. Ihe gasket and wlndow p~nel a66embly i6 6ecured to the recessed portion 14 by ~ean6 of an s~)e6ive material 20 without the need for ~echanical fastener6 pro~rudLng throu~l aperture6 ~n ~he body panel. Ey elimlnating the need for such fastener~, the cro6s-6ectional profile of the ga6ket nember 1~ Day be m m imlzed ln Drder to provide a anooth relatively unobtru6ive fit with the body panel 12, thereby red~cing the aerodynamic drag on ~he vehicle.
A1BO, becau6e ~he gasket member ~nd window panel ~6semb1y 16 6ecured and bonded Eubstantially continuou61y around it6 periFhery, the window panel effectively beccne6 part of the b~dy 6tructure and i6 not 6ubjected to ~he localized 6tress ooncentration6 cau6~d by discrete mechanical fa6tener6.
Ihus the windcw panel 16 can be thinner And lighter in weight than those previously used. Optionally, however, lf direct bonding between the body panel 12 and the ~in~cw panel 16 i6 defiired, the ~indow gafiket n~ber 18 may optionally be formed with a channel-6haped opening 24 e~tending the~e~,rough in order to ~llow ~ r~uitable adhesive to bond the windcw panel 16 directly to the recefified portion 14. Such optional c~lannel-r~aped openins 24 ~ay consi6t of either ~ 6ingle opening extu ding ç~ntinuou61y througho~t the entire w~ndrhw gasket member 18, or A 6erle6 of discrete channel-shapr~ openings at ~Faced locati~l6 throughout the window gasket Ir~er.
As will becx~le apparent from ~he discussion below, ~he window gazket nlember 18 may al60 ~ptionAlly include e coatlng of pigmented n~terlal either on lt6 entire exterior surface, or on ~ p~edetermined portion thereof, a6 ~luzt~ated by referen oe numeral 26. ~uch coating of .~_J~ 3 ~

plgmented m~terlal c~n be applied to the window g~ket member 18 dur~ng the molding pr~ces~ ln order to provide a decorative etripe on lt6 exterior surface, or to color the window ,ga6ket member ln order to oomplement the color Ech~me cf the vehicle~
The window ga6ket ~ember 18 i6 preferably molded from a multi-constituent materialr BUCh a~ liquid ure~hane material for ex~mple.
~uch urethane naterial ~y be oompc6ed, for example, of a polyol re~in constituent, an i~ocyanate constituent, ~nd a c~taly6t. Example~ of ccnnercially-avall~ble polyol res m~ ~re nanufactured by Ihe DCW Chemical Curpany under ~le tradama~k voR~NoL and by Texaoo Chenical CbTpany under the trademark q3L~NaL SF-65~3. Examyles of commerci~ ocyanates are produced by The ~pjohn Cbmpany under the trade~ark6 ISCN~IE 143L, ISaNAlE
181, ISCNAl~ 191 and ls~rE 240, ~nd al60 by ~cbay Chemical Gorporation under the trademark~ MONLUR PF anæ MaNDUR CD. An example of a 6uitab1e catalyst for ~ch urethane materinl ir~ marketed ~y Wltco Chenlcal Cbn~any under the k ademark WlTCO ~OMRE~ ULr2B.
A6 illu~trated ~ematically by the reaction injection molding 6ystem 30 in Figure 2, the oon~tltuent6 of windcw gasket material are injected from two or more constituent 60urces 32 and 34 ~nto a Zo h~gh-pressure mixing apparatu6 36 by way of the respective metering device~ 38 and 40. ~he oon6tituent~ of the material nre mixed ~n the high-pre~fiure mixing appara~u6 36 at pre66ure6 in the rhnge of approximately 2000 p.~.l.g. to approximately 3000 p.~.i.g. and are conveyed to an a~termixer and ga~ing apparatus ~2. A~ di6cu~sed below, the atermixer and gating apparatus ~2 further n~xe~ the con~tituent~ of Lhe gasket material and reduce6 lt6 pre6~u~e to A range of approximately 30 p.6.i.g. to ~pproximately 100 p.6.i.g.~ and preferably approxi~ately 50 p.~.i.g., before introducing ~he material lnto a mold cavity 44 of a mold a~ratu~ 46.

~S,J~

Prior to the lnjection of the ~ultl--aon~tituent gaGket n~terial lnto the mold ~pparatu~ 46, the ~ld c~vity iE; preferably coated with ~ly of n number of known mold relen6e agents, which typ~cally confii~ of low-nælting point wa~es or ~ilioon 0116, for ex~mple. Ccmmerclal example~
of ~old relea6e agent6 are F~oducrd by Contour Chenucal Cbmpany under the tradmark ~Rrxo 1711, EXI~T lI, l~ULEA6E 125, LIFFI ~n~ NCNSTICKENSTUFFE, by Frekote Inc. under ~he trademarks ~REXCTE 34, FREK~TE 34H, F~ERCrE 31, ~nd FREXoTE 31~, ~nd by Palk Chemical Comçary under the t~ademark PRC7B9.
The volatile moJd release agent ~6 then all~wed to at lea~t partially flaEh off of the n~ld spparatu6 which is typic~lly at ~ temperature ~n the range of approximately 110~ ~o approximately 160F.
If desired, all of the mold cavity ~urface, or A predetermined portion thereof, may be coated with a pigmented materlAl 60 that the pign~nted material will be transferred ln the mold to the desired 6urface or 6urfa oe s of the g36ket or other molded article during the reaction injection molding proces6. An exa~ple of 6uch piymented material coating i6 n~nufactured ~y S}lerwin Williams Cbmpany under the trademark PULA~E.
~fter the pig~ented naterial coating ha6 been ~llowed to flash off, the window panel 16 is po6itioned in the mold and the mold ~ n~ers 48 and 50 of ~,e mold apparatus 46 are closed, sub6tanti~11y in mu~ual engagement with one another. ~e oonstituent6 of the gasket ~aterial are injected into the 6ystem~ mixed and introduced int~ the mold cav~ty 44 as described above, and the window panel 16 with the window gaske~ 18 integrally m~lded thereon i6 then renloved.
AS i6 known to tho6e 6killed in the reaction in~ection ~olding ~rt, the lntermixed con6tituent~ of ~he ~olding raterial underqo ~ rapid And hig~ly exoLhermic reaction ln the mold cavity and are approx~mately 70% cured wi~hin ~ very ~hort time, generally les~ th~n one to ~lx ~ninute6, depending upon the cataly~t employed. After ~uch time, the ,~ 3~

Dolded article nay be remcved frQ~ the ld~ng ~pp~ratu~ ~nd ~llw ed to cool ~t ~mbient ~amperatureL.
~ illustrated ln Figure 3, ~t le~6t one, and preferably both, of the mold nenber~ 4~ nnd YO include an elongated el~fitomeric bead nember 56 oompres6ingly seated within a corre6ponding groo~e 5B~ qhe grocve6 58 are po6itioned gener~lly ~djacent the peripher~l edye~ of the nlold cavity 44 60 that the ela6tomæric member~ 56 ou~prec6ingly engage and Eealingly 6upport either the opposite nold nember or the window panel 16 and al60 6ubs~anti~11y prevent or nini~lze fla~hing of ~he lding n~teriAl out fro~ t})e mold c~vity ~4. When the mold apparatus i6 open, the ela~toleric ~anber6 56 preferably protrude slightly from thelr as60ciated grooves 58 so ~hat the ~orce required to hold the mold member6 48 and 50 together ~n a ~ealing engagement i6 6ub~tanti~11y reduced from the force that would be nece~6ary if the mold member6 were required to be fo~ced into direct contact with one another. SLmilarly, s 61gnificantly reduced pres~ure i6 exeIted on the window panel 16 and consequently ~le frequency of breakage of the window panels i6 r~ub6tanti~11y minimized or eliminated. Such reduction in the force required to hold the mold n~3nber6 together i6 al~o 6ignificantly less than that required in oonventional oallpres6ion and injection molding processe6. Additionally, the ela6to~erlc members 56 are 6ufficiently flexible to allow for minor variation~ ln the 6hape and contour of the windcw panels and thereby sealingly i~olate the mold cavity 44 regardlec6 of ~ch minor window panel variations.
Figure6 4 and 5 illu6trate ~n improved atermixer and gating aE~aratu~ 42, genernlly including an arter~ixer block or body 64 and a gating block or boay 66 po~ition in one or the ot21er of the ~old menbers 4B
or 50 for further mixlng the congtituent6 of the gasket material and a~nittLng the materi~l to the ~old cavity 44.
The Altermixer body 64 lnclude6 at least one con~on inlet ~ 3~ ~ ~3 pafi6a9eW~y 68 for r~oeiving tbe gAfiket ~teri~l from the hl~-prefifiure ~lx~ng appalatus 3~ ~t a pre~etenmlned flo~ rate ~nd prefifiUre. The gafiket materinl fiows through the inlet pafifiageway 6B into nt le~fit a pair of curvilinear mlxing pas6agewayfi 72 ~nd 74 ~here it i6 ~eparated into D
correfiponding number of flow ~tream6. ~uch ~eparation lncrea~e6 the turbulence of the gafiket material flow ~nd accordingly enhance6 the internlxiny of lt6 oonfitituentfi. ~e mlxing pafisageways 72 and 74 include a divider wall 76 therein, ~hich fonm ~ generally serpentLne path in the mlxing pa~sageway6. Such EærFentine path includefi at leafit one bight portion 78 in the mlxing passageway 72 ~n~ a similar bight portlcn 82 ln the nlxing pas~ageway 74. ~uch bight portions CaUBe the gasket material to 6ub~tantially reverse it~ direction of flow, ~ indicated by the flc~
arrows 8q ~nd 86, re6pectively, in order to i~crease the turbulence of each of the gasket material flow streams and enhance the inter~ixing of the constituents therein.
~)ce the gasket material flow6 through the mixing pa6sageway6 72 and 74, it enters a corresponding number of respective inlet openings 88 and 90 of at least ane cxr,lmon mixing cavity 92. The flow streams from the rixing passageways are reunited in the mlxing cavlty 92, which again reverses the flow directions of the flow stream6, incrense~ their turbulence, and enhances the lntermlxing of the gasket material conStituents. The reunited and intermixed gasket material fram the mixing cavity is received by the inlet pHssageway 94 in the gating body, wherein it i6 conveyed through ~ diverging fan-gate passageway g6 to the mold cavity 44.
~ he aftermixer body 64 preferably i~cludes n ~tepped or ofset porticn 102 adapked ~o slidLngly engage n preferably corresponding ~tepped or offEet portion 104 on the gating bo~y 66, guch ~hat ~he altermlxer body 64 and the gating bo~y 66 nay be slidably ~nd adjustably moved toward or ~way from one ~no~.er n~ lndic~ted by tbe arruw% 106 and 108. nle gating b¢dy 66 ~l~o lnclude~ ~n integrrlly-fon~ed tongue portlon 110 in ~hich the gating inlet pn~6ageway 94 i& for~ed. ~he tongue portion 110 1~ rlidably ~eceived in ~ ~lot 112 in the ~ftenml~er body 64 for elld~ble and ndju6t~ble ~ove~ent thereln ~B the ~ftermi~er ~nd gating bodie5 are ~d~u~tably noved ~s descri~ed ~bvve. ~e ena portlon 114 of the tcngue portion 110 def~ne~ tbe e~it portion of the mixing cnvity 92 ~uch that 6slective nL~ement of the tongue pcrt~on 110 in the ~lot 112 all~w6 the 6ize6 of the mi~ing cavity 92 and it6 inlet openingc ~8 Dnd 90 to be eelectively ~ltered e8 the aften2ixer ~nd gating bodie6 are 6~1ectively and ~dju6tably moved. Ihu6 the slze6 of the mixing savity snd lts inlet openings may be Eelectively ~nd ~dju6tab1y increa~ed a8 the aftermixer and gating bodie6 are ~oved apart from one another, ~nd corre6pondingly 6uch 6izes may be 6electively and ~dju6tably decreased a~ the aftermixer ~nd gating bodies a~e ~oved toward one another. In order to fill the unoccupied gap in the slot 112 ln the aftermixer body 64 after the aftermixer body has been adju6tab1y moved away from the gating body 66, one or more shim rembers 120 are removably ln6e!table into the 610t adjacent the end portion 114 of the tongue 110.
The aftermixer body 64 16 preferably provided with one or more elonga~ed opening6 124 the~ethrough for receiving ~ threaded fastener 126 extel)ding therethrough. The threaded fa6tener i6 adapted to threadably engage a threaded aperture 12B in the gating body 66 and cerves a~ a locking ~eans for fixing a pre6elected po6ition of the tongue portion 110 ln the 610t 112. Preferably, the a~tenmixer body 64 i6 al60 prov~ded wlth c~unter6unk portion~ 13D for ~llo~ing the head portlon6 132 of the a~tener6 126 ~n ~ rece66ed relatlon6hip wlth the 6urface 134 of the aftelmi~er body 64.
The above-de~crlb~d select~ve ad~u~tment6 to ~he 6i~e ~f the ^r~

~lxing CAVity ~2 ~nd lts ~nlet vpening6 94 ~nd 96 allow for the ~elective alter~tion of t~e back-pre~sure e~erte~ by tbe rfter~lxer 3nd gating ~pparatus 42 on t~e ga~ket material flcwlng therethrough. ~u~ alteration thereby ~llcw~ for ~le 0ælectlve optimization of the intermlxing of the con~tituent6 of the ga6ket ~ateri~l for ~ predetermined flow rate ~nd pre~sule of the n~terial from the high-pre~ure mixin~ ~pparatu6 36 Ehown ~ematic~lly in Figure 2. ~y ~uch adju~bments, ~lerefore, the u6er of the reaction injection molding ~ystem may ~fine-tuner the proce~6 to nchieve optimum lntermixing and reaction of the constituent~ of the lding materi~l a6 well a6 achieving greater control over the pre~6ure at whidh the ~olding material i6 introduced into the mold cavlty~
m e foregolng di6cu66ion discloses ~nd describe~ ~xemplary embodin~nt6 of ~le pre6ent invention. One Ekilled in ~he art will readily reoognize from 6udh di6cussion that various dhanges, rcdifications and vari~tion6 ~ay be made therein without departing fram the 6pirit and ~cope of the invention as defined in the following claim60

Claims (21)

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

1. An aftermixer apparatus for use in a reaction injection molding system adapted for fabricating articles from a multi-constituent material, said apparatus comprising:
a mixing body having at least one common inlet passageway therein for receiving said multi-constituent material in a pressurized flowable state and at a predetermined flow rate;
a number of mixing passageways in fluid communication with said common inlet passage way for separating said material into a corresponding number of material flow streams;
a common mixing cavity having a number of cavity inlet openings in fluid communication with said mixing passageways for receiving said material therefrom, said number of inlet openings corresponding with said number of mixing passageways; and adjustment means for selectively altering the size of said inlet openings of said mixing cavity in order to selectively alter the back-pressure on said material flowing therethrough, thereby selectively optimizing the intermixing of said constituents of said material for said predetermined flow rate.

2. An apparatus according to Claim 1, wherein said mixing passageways follow a generally serpentine path in order to enhance the intermixing of the constituents of said material in said flow streams.

3. An apparatus according to Claim 2, wherein each of said serpentine mixing passageways includes at least one bight portion adapted to cause the material flowing therethrough to substantially reserve its direction of flow at least once as it flows from said inlet passageway to said mixing cavity.

4. An apparatus according to Claim 1, wherein said adjustment means is adapted for selectively altering the size of said mixing cavity.

5. An apparatus according to Claim 4, wherein said apparatus further includes gating means for conveying said intermixed material to a mold cavity, said gating means including a gating body connected to said mixing body gating inlet passageway in said gating body and in fluid communication with said mixing cavity for receiving said material therefrom, said gating inlet passageway being formed in a tongue portion of said gating body, said mixing body having a slot formed therein, said slot extending from said mixing cavity generally toward said gating body and being adapted to slidably receive said tongue portion of said gating body therein, an end of said tongue portion being configured to define a portion of said mixing cavity so that the sizes of said mixing cavity and cavity inlet openings increase as said tongue portion is slidably moved in said slot in a direction away from mixing cavity and the size of said mixing cavity and cavity inlet openings decrease as said tongue portion is slidably moved in said slot in a direction toward said mixing cavity.

6. An apparatus according to Claim 5, further comprising locking means for fixing a preselected position of said tongue portion in said slot, said apparatus further comprising shim means insertable into said slot for substantially filling the unoccupied portion of said slot when said tongue portion is slidably moved in said direction away from said mixing cavity.

7. In a reaction injection molding system for fabricating articles from a multi-constituent material in a mold cavity, said system including mixing means for intermixing the constituents of said material and gating means for conveying said intermixed material to said mold cavity, the improvement wherein said mixing means comprises:
a mixing body having at least one inlet passageway therein for receiving said material in a flowable state;
at least two generally serpentine passageways in fluid communication with said common inlet passageway and being adapted for separating said flowable material into a corresponding member of flow streams; and a cavity in fluid communication with said serpentine passageways and being adapted for reuniting said flow streams, said cavity being in fluid communication with said gating means for conveying said intermixed material thereto.

8. The improvement according to Claim 7, further comprising adjustment means for selectively adjusting the size of said cavity.

9. The improvement according to Claim 8, wherein said cavity includes a number of cavity inlet passages for receiving said material from said flow streams therethrough, said adjustment means further being adapted for selectively adjusting the size of said cavity inlet passages.

10. The improvement according to Claim 7, wherein each of said serpentine passageways is adapted to cause its corresponding flow stream to substantially reverse its direction of flow at least once between said common inlet passageway and said cavity, thereby creating an increased turbulent flow condition and enhancing the intermixing of said constituents.

11. The improvement according to Claim 7, wherein each of said serpentine passageways includes at least a pair of curvilinearly-extending portions interconnected by a bight portion therebetween, said flow streams being caused to substantially reverse their direction of flow at said bight portions.

12. The improvement according to Claim 7, wherein said gating means includes at least one gating inlet passageway for receiving said intermixed material from said cavity, and a fan-gate passageway extending between said gating inlet passageway and said mold cavity.

13. A reaction injection molding system for molding articles from a multi-constituent material in a mold cavity, said system comprising:
a source of said multi-constituent material in a partially-mixed pressurized flowable state;
at least one aftermixing and gating apparatus for further mixing said multi-constituent material and for conveying said material from said source to said mold cavity, said apparatus including a common inlet passageway, at least a pair of generally serpentine mixing passageways in fluid communication with said common inlet passageway, a common mixing cavity in fluid communication with said mixing passageways, said common mixing cavity having cavity inlet openings for receiving said material from said mixing passageways, a gating passageway in fluid communication with said mixing cavity for receiving said material therefrom and for conveying said material to said mold cavity, and adjustment means for selectively altering the size of said cavity inlet openings; and a mold apparatus including a first mold member and a second mold member mutually engageable with one another and defining said mold cavity therebetween, at least one of said mold members including at least one elongated elastomeric member thereon generally adjacent an edge of said mold cavity and extending generally around the periphery thereof, said elastomeric member supportingly engaging the other of said mold members and being adapted to substantially prevent flashing of said material out of said mold cavity.

14. A reaction injection molding system according to Claim 13, wherein said aftermixing and gating apparatus includes an aftermixer body and a gating body slidably connected thereto, at least a portion of said gating passageway being formed in a tongue portion of said gating body, said mixing body having a slot formed therein, said slot extending from said mixing cavity generally toward said gating body and being adapted to slidably receive said tongue portion of said gating body therein, an end of said tongue portion being configured to define a portion of said mixing cavity so that the sizes of said mixing cavity and cavity inlet openings increase as said tongue portion is slidably moved in said slot in a direction away from mixing cavity and the sizes of said mixing cavity and cavity inlet openings decrease as said tongue portion is slidably moved in said slot in a direction toward said mixing cavity.

15. A reaction injection molding system according to Claim 14, further comprising locking means for fixing a preselected position of said tongue portion in said slot, said apparatus further comprising shim means insertable into said slot for substantially filling the unoccupied portion of said slot when said tongue portion is slidably moved in said direction away from said mixing cavity.

16. A reaction injection molding system according to Claim 14, wherein said mold cavity is adapted to receive a window panel inserted therein prior to the introduction of said material into said mold cavity, said article comprising a window gasket member molded in place on an edge portion of said window panel within said mold cavity.

17. A reaction injection molding system for molding window gaskets or the like, from a multi-constituent material in a mold cavity, said system comprising in combination:
a source of the constituents of said material in a pressurized flowable state;
means for receiving and intermixing said material constituents from said source and for conveying said intermixed multi-constituent material to said mold cavity at a predetermined pressure;
a mold apparatus including at least a first mold member and a second mold member mutually engageable with one another and defining said mold cavity therebetween, at least one of said mold members including at least one flexible elastomeric member thereon generally adjacent an edge of said mold cavity and extending generally around the periphery thereof, said elastomeric member supportingly engaging the other of said mold members and being adapted to substantially prevent flashing of said material out of said mold cavity, said mold cavity being adapted to receive a window panel inserted therein prior to the introduction of said multi-constituent material into said mold cavity, said window panel being sealingly supported between a pair of flexible elastomeric members.

18. A reaction injection molding system according to Claim 17, said window gasket member being molded in place on an edge portion of said window panel within said mold cavity and substantially embedding said edge portion therein, said window panel and gasket member assembly being adapted to be bonded and secured to a peripheral area surrounding an opening in an external member with an adhesive substance without mechanical fasteners.

19. A reaction injection molding system according to Claim 18, wherein said multi-constituent material comprises urethane.

20. A reaction injection molding system according to Claim 17, further comprising means for coating at least a predetermined portion of said mold cavity with a pigmented material prior to conveying said multi-constituent material thereto, said pigmented material being adapted to be transferred to at least predetermined surface portions of said multi-constituent material as said molded article is formed in said mold cavity.

21. A reaction injection molding system for molding a window gasket member from a multi-constituent material in a mold cavity, said system comprising a source of said multi-constituent material in an intermixed pressurized flowable state, and mold apparatus including a first mold member and a second mold member mutually engageable with one another and defining said mold cavity therebetween, at least a portion of said mold cavity being adapted to receive a portion of substantially transparent window panel inserted therein prior to the introduction of said material into said mold cavity in order to mold said window gasket member in place on an edge portion of said window panel within said mold cavity.