CA2069844A1 - Window stay - Google Patents

Abstract

SUBSTITUTE
REMPLACEMENT
SECTION is not Present Cette Section est Absente

Description

- 1- 2~984~

My p~esent invention compri~e8 a ~rl¢tion ~t~y ~c,r A window~

A variety o orm~ of friction stay~ ~or window6 are known. ~he four bar window ~tay the ~u~je~t o~ ~ew 2ealand p~ent Mo. 1449~14hl~U114b~ or example, h~
~or over ~wo de~Ades proved p~rt~c~l~rly ~ucce~ful in 1tB
bas~e and ~u~equently re~ined form~, in m~ny countrle~ o th~ world. The ~Ucce86 ~f thi~ four har fr~ction ~ay h~s derived from it~ ~implicity o~ con~tructlon, ~ec~e ~he ~tay doe~ no~ h~ve the extern~lly exposed ~lidin~ pivot and track a~-rangement o~ pan~o~raph type et~y3. 5uch externally expox~d movinq ~arts ~r~ prone with time to clogging wi.~h dirt ~au~in~ ~ticking of ~he mechanLsm~
increa~ed we~r and tear and so forth. Al~o, the geometry ~nd operation o~ ~he fo~r ~ar stay ln use lift~ the windo~
sa~h ~ut o~ the window apertur~, ena~ling thc provi~ion of a periph~ral ~ealing flange about the entlre ~h while still facilita~in~ ac~es5 for cleaning.

: With conventi~nal ~ur ~ar frlction ~tay6, ~ven when the window ~ash i9 clo~ed, th~ ~tny ~ tsel~ 1~ a~ a few degree~ open. lt ~ bel1~d neces~ary that even whon the window ~s~h i6 clo~ed, the ~riction ~t~y not ~e fully clo~ed to ensure correct opcratlon o~ the ~t~y when the window i~ again opened. with the four bar g~ometry, de~ignex3 ha~e en~u~ed th~t the stay ~s sl~gh~ly open ~v~n ~hcn the w~ndow is clo~ed bec~use of the dangcr ~hat oth~rwise thc ~tay might not operate correctly ~nd th~t - 2 ~ 2 ~g9 8 44 ~he head of th~ window could begin to move ou~wardly before the bottom o~ the window s~h, whlch would result in jamming of the ~tay.

WlndGwei produced f rom uPVC ln~te.~d of ~lum~nium or wood have beoome popular, ~artlcularly ln the replacement window market. The uPVC ~aterial i~ p~oduced ~y ~xtru3ion ;~nd ls then cu~ a~nd th~ windo~ ~aall~e~) ~n~l frame(~ are con~ructsd. A common ~and~rd ~PYC

extru~lon pro~lle ha~ a cavlty co2npri~ing a n~ W ~o~r~
to acco~modate the ~tay ~etween the 6a~h and frame to ~ui~
pa~ LA~ ,y~ dy~ a~ wllL~_ll W~ V~
co~lventional four bar ~ay. Although the ~our bar friction stay i~ ~uperior, it ha~ no~ ~een pos~i~le to ~mploy a our b~ ~tAy.

A1BO~ becau~e ~he four bar fr~c~ion stay ha~ not been allowed to clo~e fully, for various rea~on~ thi6 h~s i~hibited the u~e of ~ome ~orm of integral head loc~in~
mechanism with ~.he fou~ bar ~tay. Some ~orm of h~sd locking mechani~m 1~ desirable bec~u.~e of anoth~r disa~antage of the fo~r bar ~tay, ~hieh is thA~ the head can }:~e forced open ~rom ou~icle the window frame, ~y leverin~ b~ween the peripheral ~eal~n~ ~lange ~t the he~d of the ~indo~ and the window f rame wi~h ~ crowha~ fo~
example. A ~eparate lo~king d~vice c~n h~ ~dded ~etw~en th~ ~indow sash and frame on ~he in~lde o the window to counter ~hi~ dan~er, bu~ ~hlB ~ n~t a~ de~ir~ble as i~ ~n integral mech~nism C~I~L~ be u~e~ . ~or a~ lon~ ~ th~ f ou~

- ~- 2069~

b~r friction stay h~s l~e~n produ~ h~e problem~; have r~mained, My pre~enk invent~on provide~ ~n improv~d or a~
îea~;t alternatit7e form of frickion window gl~y which pos~esse3 advantage~ over the conventlonal four ~ar ~t~y ~9 will be de~:rib~

In 3~ro~cl te,rm~ the invention ~ompri~e~ A four b~r f ric:~i.on window ~t~y f or mounting A window sash ~ n a win~ow frame, compri~inq a lower arm and a pivot ~oint betwePn the rame ~ b~ the lowe~ arm and a ~aln~
mounting member .(a~ L~ill C~e:l~irl~2d3 i~O1- ~e~uring to the ~rame of a window and a ~iv~t ~int between the ~h en~

of the lower arm and a s~sh mounl:ing menuber ( a~ herelh defined) for ~ecuring to the ~h of the win~ow, ~n upper arm and a pivot joint between the sa~h end of the ~pper a~m and ~he ~ash moun~ing member ~t ~ pO~nt gp8ul!ll f LOnl the lower arm-~ash mountlng m~nlber pivot ~oint and an off~et pivot joint between the f;~ame en~ OI the slpper ~rln and th~ f r~me mollnting memb~r at a poLnl: ~pac:ed f rom the lower arm-frame mountin~ me~er pivot joint ~aid off~et pivot jolnt being sufficiently ofset ~rom ~ llJle pa~
x~t~nti~lly throu~h ~he other p~ vot joint8 wherclsy wh~n the willdow e;tay is ~ully clo~ed the lowex arm ~nd ~h moL~nt~ng ~ r are ~ligne~ and the uppe~ ~rm extend~ a~
~n angle from the upper ann-~a~h mollnting member p~vot joint away rom the ~a~3h ~noun~ing member to 0ald top arm- fr~me mounting mern~r off~t ~ivot ~olnl~, wi~;h a~

- 4 ~ 8 4 ~

lea~t some of ~aid pivot ~oint~ being frl~tion pivot joln~.

Preferahly the ~tAy o the Lnvent~on incorporate~ integral me~n6 to lock the head of the ~tQy again~t forced op~ning, comprl~ing frame engag~ng mean~ on the upper arm end of the ~a~ mountLng me~her whlch eng~ge~ sash engaglng m~ans on the ~rame moun~iny me~ber as the ~tay is clo~ed, with the di3t~nc~ be~ween the ~pper ~rm-~ash mounting m~mber p~vot joint and sald fr~e en~a~in~ mean~ on the end of the s~3h mounking membe~
~eln~ le~ than two thirds, all~ mo~t prefera~ly le~ th~
one half, of ~he length of upper arm between pivot ~o~nt cen~reo.

In a mo6t prefexred for~ a~ will be de~cribed, the frame engaglnq means aompri~e~ a protru~lon ~ro~ ~he end of the ~a~h mo~nting member and the ~a~h engaging mean campri~e~ a rece~s into which the p~ot~usion en~ges the ~tay rea~he~ ~t6 fully olo~ed po~ition.

Preerably the length o the upper ~Lm betwe~n pi~o~ joint centre~ i~ between one half and three q~r~er3 of the length of the lower ~rm ~et~e~n pl~ot ~olnk ~n~ee.

In term~ of d~sn~ion~, in ~yp~c~l ~ize~ of ~t~y~ in ~ommo~ ~e, the off~t pivot joint i~ pre~er~bl~
of~et from said line p~in~ ~ubstant~ally tilrougll ~he 2~6~8~4 othex pivot joint~ by between 10 and 4~ mm and mo~t p.efera~ly between 15 ~nd ~0 mm, me~ured be~ween ~id line and the ~entre of the of f 6et pivot jolnt . The angle ~etween the upper arm an~ the s~Sh mo~ntlny m~ wl~bn the stay i~ clo~ed 1~ p~eerably hetween 13 and 20 degreee ~nd mo~t prefer~bly about 15 degree~.

Mo~t preferably the Lame moun~ing member of the ~tay of the invention i~ formed of a pla~tlc~ mat:er~l and the pivot joint~ between the frame mountlng me~ber ~nd each of the arms o~ ~he Btay ~omprl~e may then be of pre~erred form in which at e~ch joint an annul~r ~houl~er o~ the pl~stic m~terial of ~he body o~ the frame mount~ng member proj~ts from the fr~lle ~oun~ing m~mber, there ~ ~
an aperture in ~h~ arm whercby the ~rm i 6 located for pivotal movement about ~h~ oul~er, nnd ~ ~lxing ~ean~
for fixin~ the jvint and applying frict~ on crea~in~
pres~ure extend~ throuyh the ~oint ~nd i~ flxed withln th~

~houlde~ and/or ~i~hin ~n aper~uL-e in a fra~e mountin~

member below the ~houlder, witll pla~ic~ m~erl~l sxtending from the Ghoulder hetween the arm anA ~iXill~
mean~ to prevent direct cont~t therebet~en. ~hi~ ~orm of friction pivot joint will be de~cribed f~rther l~ut other ~orms o~ friction pivot ~oint~ ~ould be u~ed, ~u~h a~ the ;oint descri~ed 1ll my }~c~ 2e~1ancl ~tent ~pecifi~a~ion 21~5~/Au~tr~ n patent ~pecl~i~at~n 5B7~2~Eu~pean ya~ent sp~ification 86305015.2~U~ p~t.en~
~pecificatio~ 4,721,~06/~apane6e pa~nt ~pe~ific~tio~
6084/~7 which i9 incorp~rated herein ~y refe~en~e ~or - 6 - 2~6984 de~rlptlon Of thl~ frlc~lon pLvot joln~. L~ot~ th~e pivo~ jo~nt~ have a hollow ~ LI:' VJhiC'Il AllOW~ crew3 ~o~
fix~ n~ the ~tay to a window ~rame (or snAh) to b¢ ~cre~ed thr~ugh the plvot jOil~t, ~30 ~ha~ lo~ds ~re t~ken directly at: the elld~ of the st~y ~rm~.

The stay of my invention i~ ~uital~le f or u~ ~n both awning and ca~ement appli~a~;~ on~. With the ~ y of the invention when ~h~ window i~ ~lo~ed the ~te.y i9 also fully clo~ed i.e. the ~ash moun~ing member and lower ~rm are fully allgned . ~hls allow~ the ~ta~t ~o ~e llB~ W~ ~h ~ommon ~tandard uP~C window prc,f iles . Al~o, in in ~ ti~l opening the head of the 6tay ha~ a sl lght downward ~nd t.herl ~n outward nlovement. Thi~ enable~ the stay to employ an integral head locking meohani~m, 1~ de~ired. Th~ ~a~h mounting point~ of tlle s'cay n~ay be properly ~p~ed apart givinq good sa h stability when the s~sh i~ open and the ~tay pOSse~;Be~ a hlgh d~gree of inhe~ent ~itrength.
Forming the ~xame mounting mem~er or ~ pl~tc~ cs~ h pla6ti~s material with the pre~erre~ CQn6trUCtion desc~ihed, ena~les the number o~ componen~s u~ed to produc~ a pair of ~'cay~ to ~e halved~

A preferred form of the fricti~n ~t~y c~f the inventic~n is illust:rated, ~y wa~ o~ ex~ffl~

~c~ompanyilly dL-~wlng~l wh~

_ 7 _ 20698~

Fi g. 1 ; ~ ~ vi ~w f ~ pr~rr~d f~rm window stay o~ the lnvent ~ on from one ~ide in it~ fully ex~cended or open po~iti~n, Fig . 2 i~ ~ view ~ the ~ y c)~ Fig . 1 ~n ~ t~
ed po~iti ~.n, Fiq . 3 i~ ~n end v~ew of the pre~erred ~4rm ~t~y in the direction of arxow ~ ln Flg. 1, Fly . 4 i~ ~ cros~-~ectlon~l vlew o:l: a ~:rlct~ ol, pivo~ int of the in~n~lon ~etween a rame plate ~nd an arm, also Rhowing a mounting f~icrew a would be u6ed in practlce ~or mountlng the s~ay ~o ~ wln~w ~ame, ~ lg. 5 ls a view fron~ ve a~ the p~uL~
form joint twith no mountinq ~c:re~ ~hown), Fig, 6 i~ a cross-~ec~ti~nal view through the ond of the frame plate o~ Fiy. 4 w.~tholl~ th~ ~rm, ~ x~ng mean~, and mounting ~cr~:w of F~ g . 4 ~

Fig . 7 i~ a view f rom ~bo~7e ~ tlle end c~ the f ra~ne plate ~hown in Fiy . 6, in t:he dir~ction of alrrow D
in ~ig. ~, Fig~ B is a cross-~ct~on~l vi~3w through a pr~erred fvrlla but~on ~ixlng me~n~, 2~6~844 ~ ig. 9 is ~ view from above o~ the prh~rr~d forrlt button fixin~ mean~ in the direction o~ arro~ E ln Flg, ~, Fig. lOA 1~ a cro~ sectic:n~l vie~ of a form ~f joint r~lated to th~t o Fig~. 4 ~co 7 for optionA1 u~e b~t~een an arm and a metal sa~h pla~.e ~hen the ~h plAt~
i5 not also formed of pla~tic, ~igs lOB ~nd lOC showin~
~'ceps in a~emk~ly o~ the ~olnt, ~nd Figs l lA, l lB anl 1 1~ are vle~ ltl ~ b f ~r each of ~iga lOA~ B ~nd C .

Flef~in~ to Fig6 1 to 3 the prefe~ed form ~y illuGtrated in th~ drawing6 conlpri~e~ ~n upper ~rm 1 and ~
lower arm 2 . The ar~n~ are pref erably ~ormed ~r~m e'cainle~ st~el or aould alt~rnatively be form~f~ of aluminium, for example. The frame end~ of the upper ~nd lower arm~ 1 and 2 Are pivotally connected to a r.~m~
mounting mem~er compri~ing a f r~me plnt~: 3 o~ securln~ to the frame of a window, by way ~f ~uitabl~: friction p~vot jOint~ 4 ~nd 5 i).s ~ 3 fu~ther deE~cribe~, at point;~
6paced from ea~h other~ In the pref~rred r.o~m ~y ~hown in the d~2lwings the f r:~me p~ ate ~ ormed by in jection ~noul~ing f~c~m a pla~tic!~ mat~rial suGh a~ Qcctyl or oth~r 5~1f l~r~catirlg and ~f3~r re~i~tant syn~hatic mu~;eri~l, but the ~rame plate 3 coul~ alter~ t;ively b~a f o~me~ o~
rnetal such ~a atainlee~ ~teel or ~lumln.~ um.

20~.~8~

The sA~h end~ of the upper arm 1 and lower arm 2 are pivotally con~ ed ~c, ~. sash l~luu~ ly m~m~*r ~ompri~ing a ~h plate 6 for 6ecurin~ to the ~a~h of ~he window, by way of ~ similar p~vo~ jo~n~s 7 and 8 which arç
preferahly al~o frl~tlon plvo~ ~oln~s, at pOl~e~ ~p~d from each other. Where the f rame plate 3 ~ ~o~med f rom pla~tic3 mater.ial, the sa~h plate ~ is preferably al~o formed of a pla~tic3 materi~ ut ag~ln ~he ~a~h pl~te ~ould altern~tlvely he fc~smed of met~l BUCh a~ ~talnl~g ~t~el or aluminium. I~ form~d from met~l th~ fram~ and ~h piate co~ld he po~rder co~ted f~ e~ pl~.

A land v~ extra sec:tLon of materlal provided on the f rame pl~l;e 3 a~ shown ln Flg~ 1 and 2.
Thi~ land 9 extend~ behind ~o ~ to ~e off~et from the main body of the ~r~me plate 3 a~ ~hown. The pivot jo~n~

4 of th~ f rame end 4f the upper ~rm 1 to the f ralne pl~1:e 3 i8 provided on thi~ land, so that ~;hi~ piYo~ ~oint i~ also offset. ~he upper ~rm-frame ~late pivot joint 4 1~ off~t away from a line pa~ing through the other pivot io~ nt~ o~
the ~tay when ~he ~tay is c~losed d~:l shbWn ~ lg, ~` ~ Loln~
th~ lower arm-~ran~e moun~lng meml~er pi-~ot joint s, ~lle lower arm-sa~ih mounting membe~r pivot ~olnt ~ ~nd th~ uppe~
arm-s~h mollntin~ member pivot jolnt 7, and thf~ lowe~ arm 2 and ~aeh plate ~ are ali~ned ~ ~he upper arm 1 ext en~
at an~le from the upper E~ sa~h pl~e plvot joint B to the off~et pi~ot joint 4 a~ hown, preferably of ~bout 15 degree~ or more ~ n a typical size of ~tay, In ~ typical 2~698~

~ize of ~tay the off~e~ jvint 4 Inay be offGet ~e~cween 15 mm and 30 ~n from thi~ llne.

This of f~etting of th~3 upper arm-frame pl~l:e pivot ~olnt 4 enables the st~y to l~e fully ~ s~d ~o thA~
the lower arm 2 and ~a~h pla1;e 6 ~re a~ igned wh~n the ~ y i~ in it6 closed position, in comp~risosl to conventlon~l t ~ -~ n ~ ~ h o~ c~ , h ~ n ~ hL~ ~ ~ h i~, n ~1 ~ t A y are ~n 'chelr cloE~ed po:~itionff, ~he geomet~y o~ tl ~ 3~aY 1B

not fully ~losed i.e. the lower arm and ~ash mount:lng melr~e~ are not allgned a~ ~ho~n in Fig. 2 ~lth the sta~
of the invention~ hut are 8~ill a ~ew degr~e~ ~wa~ f~
thi~ po~ltlon. P.no~ht!l d~v~nt~ge of the ~t~y of tho in~ntion i8 ~hat when the ~t~y is within ahout 10 de~reer~
of its clo~ed positlon, the windo~ sh ~ tend naturally to ~pring ~hut. ~l~his Ls ln contra~l; to 1;h~
~onventional four bar ~ay ~e~me~ry, wherein when the window i8 ~lo~ed but not lat~h~d ~hut, ~l~e ~tay ~nd ~h tenà to apring to a ~lightly open natllr~l pO6it;iOII ~f r~t .

Ea~h o~ the f ~ame and ~ash pl~te~ 3 and ~ y be provided with ~uitable moun~ing holes whereby the ~t~y may b~ mounted to a window f ran e and sa~h ln u~e O Wh~n the plVGt joint~ employed are of th~ preferred form type de~cribed here~ n ~he fra~ne Ar~d ~a~h plat;e~ 3 ~nd 6 ~sn additionally or alternati~ly be ~cl~red to t,lle frA~n~ A~
~h by ~crews or like ~;ten~rs pa~ing through the plvo~
joint~ themsel~re~ ( a~ in Fi~ . ~ ) . Thl~ dvan~aqeous, 2~8~4 particularly in ca~ement wlndow dpplicat~on~, ~3 'che frame plate i~ ~ecured to the f rame at the s~me poLn~ tll~'C lo~d~
are applied ~30 that deformatlon c)f ~he rAtne pl~t~ ia rni.n I ml ~ed .

~ n U~e the ~ y eall be moved f rom it~ f ully extended or open pOBltiOn ct~lown in Flg. 1 whereil- 'ch~ h plate 6 and a ~a~;h mounted thereto ~ ~ash not shown) extend ~;t an angle to the w~ ndow ap~rture, 'co or ~ow~rd3 it~
Glo6~3d po~ ion lor vice ver6a) ~y pulllng (or puE;hing~ c~n handl es suitably mounted t:o t;lle window 8~h. The s'c~y ~
Fiq. 1 i8 ~hown in it~ clo~ed po~ on in E'~g. 2, and the moven~ent of the ~a~h plate~upp.3r ~rm, ~a~h plate/lower Arm pivot joint~ iB as indicated by ~rrow3 Y and z in Fig. 1.
puring ~he la~t pa~t of the clc,8ing movement o~ the ~y the qood ~pllll in 1~ pr~vlded~

When the f rame plate o~ the ~t~y ~ ~ormed a4 a 6ingle component f rom plastic~ m~teri~l or example by in jection moul~ing it may have ~ rai3ed rib 10 ~long ~ t~
re~r ~dge to a~Eiist in ~tren~then~ ng the frame pla~e .
About the upper arm f~a~e-p~ate ~oin~ y l.lf th~
fr~me plate may ~e enlarged h~low tlle joint/~rm 6 nB ~
to provide a bearing Hurface which w~ 11 tend t:o ~upport l;h~ upper ~rm from helowl partic~larly in cas~mer~t application~ where the ~earlng ~u~-fac:e 11 m~y be enler~e~
fu~ther th~n ~own i de~;ire In ~ pro:fer~c~d ~orm injec~tion moulded ~kay shown" t~e land 9 fQr the o~set bearin~ i~ pro~ided on the main body of th.a f x~me plate, 9 8 4 ~

but in other form~ of ~he !itay such as stay~ of th~
invention having a metal f rame plate the f r~me plate co~ld be a~ wide ~8 is the land 9 througho~1t the whole of l:he length of the f rnm~ pl~te . The f r~Tne pl~te ( ~d aa~l-plate) eould be pre~ed from metal for ex~lhplc~

A~ 6~a~ed~ ~he ~tay o th~ l~v~ n ~ y ~ e up fully ~o that the lower ~rm and mountin~ pl~l:e6 o~ the ~tay ~re aligned when the ~tay i~ ~losed ~3 compared to ~
con~rentional four bar stay. The st~y compri~e~ a mlnimuln of externally m~vln~ part~ ~such ~ lin~3 t~Cl~.R or th~
like~ In addition the ~a~h mountin~ poin~ of the arm6 of the ~tay are properly spaced apar~ ao th~t ~:he 3~ay st~bly mount~ a window ~h . The st~y prov~des a ' li~t ~ ng out ' o~ the wlndo~ a~h type o~era~Clon ~o t:}~ aoAling strip extendinq ~bout the window ape~ure 1~ not ~;ended ~o be dislodqed, and enabling full cle~ning ~ccess. rrhe ~tay provide~ increased 'p~ll.L in ~ clurlng f in~l c,lo~ln~ 3o, the stay ha~ a ~light downward and then ou~cw~rd initLal opening moven~en~, which in turll enables the ~tay to incorporate an inte~al head ~ockln~ meahflni~m.

The preferred form of stAy sho~rl in ~ig~ 1 to 3 incorporate~ a preferred ~o~m of he~ locking mechan~ ~rn A~
will now be de~c~ibed~ ~l'he top end of the ~nah pl~e 6 ~a formed with fr~m~ ell~ay~n~ nn~ in l:he form of prot~usion 12 ~ ~iee ~ig . ~ reC~3es 13 1~ f ormed in ~n integral enlarged head 14 of the f ~ ~me pl~t~ ~ . On 1~he side oppo~ite the o~e~. bearln~ 4 ~.he protru~ion 12 ~n~i - 13- 2~S98~

rece ~ 13 e~ch have all acl jacent: ~own~rdly sloping l~nd 12a and 13a a~ eh~wn, The arr~ngement is su~h tha'c when 1;he window ~tay iB closed, the ~sa~h pl~te 6 will mvv~ ch ~hat the protrusion 12 enga~e~ intc~ the reces~ 13 as 3hown in Fig. 2. When the ~t~y is fully clo~ed and 'che pr~cru~ion 12 i~ ~ully enga~ed lnto the recrel~ 13, thc head o the window i~ loc3ced ~nd canno~ be op~ned by force or p~^islng c~pen J~etween the top o~ the ~7indow ~sh ~nd ~he wirldr~w frame. The lo~kln~ mechani.sm can ~g~i n only be operled by proper opening of the window by pu~hing on the ~ottom of the s~h fr~m withlr~.

In the ~m ~l~own ln ~he drawin~; the protrusion ormed in th~ plast~ materlal o:l t~e r~a~h pla~e, and the rece~s l~ in l:he ~o~ ~ the ~ram~ L~, L)u~ uSh~l-f orn~ of interlocXing f rame enyaging mean~ on the ~sh plate and sa3h eny~gillg me~n~ on the f ~ ame pla~e Are po~r;ible. For exampl.e, ~he ree,pectlv~ poalt;lon~ o~ t.he protrll~ion and rece~ cv-lld ~ reversed. The di~tEInce between the upper ~rm-sa~h plate pivot ~oint 7 ~nd th~
protru~3ion 1~ on the end of th~ ~;h~h pl~te ia l~ 6 th~n two third~, and ~ery pre~erably le~Y than one ~ -, o~
len~th of 'che upper arm, betwe~ cen~e~ uL tll~ pi~ot jo~nt~ 4 and 7, to ensure proper oper~1:ion o~ tho he~d locki.n~ ~ne~hani~m . It i~ pref err~d bu~ not es~ent ~ ~1 th~t ~f f set our bar 8tay8 of the invention lncorporat~ ~ he~d locking mech~ m.

- 14 - ~0~844 preferred form of fLiction pivo'c ~oint i~
~hs:~wn ln ~ig~3 4 to 7, whi ch i~ v~ry preerably employed for ~he pivot joint~ ~etween t:he urm~3 1 and 2 and ~he frame pl~te 3 of the window ~l;ay, and al~o optlbnally for f riction joint~ betwe~n th~ arm~3 and the ~3h pl~1:e ~ o~
the windc~w stay if the ~a~h plat:e i~ al~o form~3d of a pla~tic~ material. The frarre (or G~h) plate 1~ indlca~ed ~t ~. An arm i~ indlcated at: 1. An ~nnular shoulder 14 ~urrounds and pro jects f rom the periphery of an ape:~ure 15 through the fram~ plate 3 a~ ~hown. E~ 9~ 6 and 7 sho~

the shoulder integrally formed on ~he mountin~ plA'ce before forning o~ the joint. An annUl~r b~ 15 to Ll joint i~ preferably moulded a~ 6hown ~o th~t the en~ o~
the button fixing means 16 wlll n~t be exp~ed~

'i'he ~rm 2 ha~ p~rt~Lc whoreb1l~ th~ ~rm 1 is located about the ~houlder 14 . ;~n annular f ixin~ mean~ o~
button 16 ex~ends thrc;~ugh the ~oint and i8 f lxed w thf~ interiox of the annular ~houlder 14 and/or th ape~ture below, to fix the ~oint and ~pply fri.c~lon creating pr~s~ure ~hereto ~ th~t a ~r~c~on pi~ot ~int i~ pr~vided. In the preferred form the butto~l 16 iB aar~w threaded into the lnterior of the ~houlder 14 ~nd apertu~e below. Preferably a thread 16 not formed in tha in~.R~io~
wal] ~f ~he ~h~ulder 1~ ~o ~hat the ~u~on 1~ ~111 ~ap it.
~wn thre~d and bite into the plas~lc~ In~t~ri~l. It i~
po~ le t~at the button GOUl~ be f lxed ~y ~th~ ~h~n ~cr~w thr~ading, ~y barbs on the button hitlng into the - lS - 2~9844 pla~tic o~ the lnterior w~ll of the ~houlder o~ aperture below ~r example.

~ th~: buL~ lG 1~ Ln30rt:cd ~nd oaro~3d h~m~
the top part 14a ( see Fig . 6 ) o the ~houlder 1~ i~ bent over to become interpo~ed betweell the und~rs~de of the top o~ the button and the ~rm l as ~hown in ~ig. 4, ~o ~h~t there i~ no metal to me~l con~a~. Preferahly th~ top part 14a o the sh3ulder has ~ le~er wall thickne6~ ~han ~h~ main ~od~ 14b o~ ~he ~houlder a~ W~ ln Fiy. 9, which ~how6 the ~houlder before placem~nt of the arm.

The prefe~red form ~utton fix~ng mean~ l& i~
~hown in Figs 8 and ~ and compri~e~ ~ flang~ lika top portion 16a and a cylindrical body portlon 16b and which i~ screw threaded a~ ~hown. The hutton 16 LR aho~n in ~ig8 11 and 12. The hut~on pre~rably h~a a h~ w interior ~ that a f ixing screw for th~ æ~ay m~y be ~cre~ed ~hrough the joint ~ ahQwn in Fig. 7. Then ~he button ~ay h~e a hex interior ~o enable ~cre~lng ho~e of the b~ton during formin~ o~ the joint wlth a hex key, ~nd friction ~djustment a~r in~t~llatinn.

It i~ ~ery pref erred th~t th~ p~f ~1 L~d f orm ~
fri~tion pi~ot joint de~cribed ~e uæed in ~he ~t~y o~ ti~e inv~ntion when the f rame and/~r ~ash plate6 are formed plA~ic~ a~ h joints can be formed ~lth l~ mponcn~
than conventional ~rictlon pivot jvillte r Th~ æt.Ay c~n he p~oduced more economi~lly~ An~t:iler a~vantage of th~

- 16- 2~6984~

pref ex I ed f rom pivot jolnt~ i~ chat becau e they ~ nclude a central aperture th~ joint~ ~n the frAme ~nd a~ mount plateE~ can be ~screwed through~ wi~h mountlng 3Crew~
well a6 ~he mounting hole~ The ~tay ~ hen ~ecured to t:he f r~me ~nd ~ash of the window at the s~me po~ n~ ~h~t loads ~ appl~ ed by ~he ~ y ar~ tic.ul~rly in ca~emen'c ~pplicat~ons, 30 that di:3t~,.rtlon of th~ frame and ~h mounting pla~e~ i~ minimised.

F~q. lOA show6 in cro~ ection a ~orm o~ join~
relat-3~ to ~hat of ~ig6 4 t~ 7 that may optionally be used between an arm and a metal 3ash plate when the ~ash pl~te iB not ~l~o form o~ a plaxl;ics m~terlAl. The ~oint compri~e~ a 1houlder Qr llp~t~nd 17 for~ned ~rom the metal mate~ial of the ~ash plate 6. The lnterior of th~
shoulder i~ threaded for recelving a 8imil~qr thre~ed bu~on 1~. ~n annular bu~hi~ pl~.o~d ~bout kh~
~houlder to prevent dlrect contac~ h~ew~en ~ uul~
the arm, and the button. Fi~. lOC ~how~ ~h~ shoulder on th~ ~a6h plate ~efore the placemen~ o other compc~nents, and Fi~. lOB the shoulcler wi~h the ~u~hlng thereon be~ore ~he button 16 i~ inserte~ home. The bu~hlng i~ ~ ~A~
part ~8a and an upstand part l~B whicl~, simllar to the Fig, 7 jolnt, i~3 bent over ~y the l~utton 16 when i~
~crewed home. E~ig . llA ~how~ the finl~hed jo~ nt r~m a~ove wi'chout the ~rew f or f i~in~ ~che ~ay in plh~ to the windo~ ~a~, and Figs 1lC and 1lB are plan view~ fron~
above co:crespond1ng l:o ~ig~ lOC and lOB.

The fore~oing descri~es my inven~lon ~ncluding a preferred form of of frict~on pivot ~oin~, and v~rio~
alteration3 ~nd alternativet;. (~ther ~lte~htlon~ ~nd modification~ a~ ~ill be app~rent to tho~e ~k~lled ~n the art ar~ intended to ~e incorporated wl~h1rl th~ scope h~reof. In p~rticular, it i~; po~ible th~t the frf3me mountin~ rnember or frame plate and ~3ash mo~lntLn~ me~er or ~a~h plat~ could he integrally moulded into tl-e ~ide of the window f rame ~nd w~ ndow ~Gh, ~ er than being ~epara~e component6 ~hich are ~t~hed ~o the ~dP of the wind~w frame and ~h by ~crew~ or the like, whilsl; ~tlll employing th~s pri~ le of ~he in~ention, ~nd in th~ ~
~peci~lcation "frame mounl~ing member~ and ~A~h nlountlng member" ~re co ~e lnterprete~ acc~,~din~ly, ~nd ~19G in the f ollowing cl~lms .

Claims (15)

1. A four bar friction window stay for mounting a window sash in a window frame, comprising a lower arm and a pivot joint between the frame end of the lower arm and a frame mounting member (as herein defined) for securing to the frame of a window and a pivot joint between the sash end of the lower arm and a sash mounting member (as herein defined) for securing to the sash of the window, an upper arm and a pivot joint between the sash end of the upper arm and the sash mounting member at a point spaced from the lower arm - sash mounting member pivot joint and an offset pivot joint between the frame end of the upper arm and the frame mounting member at a point spaced from the lower arm - frame mounting member pivot joint, said offset pivot joint being sufficiently offset from a line passing substantially through the other pivot joints when the stay is closed whereby when the window stay is fully closed the lower arm and sash mounting member are aligned and the upper arm extends at an angle from the upper arm - sash mounting member pivot joint away from the sash mounting member to said offset top arm - frame mounting member pivot joint, with at least some of said pivot joints being friction pivot joints.

2. A window stay as claimed in claim 1, comprising frame engaging means on the upper arm end of the sash mounting member which interlocks with sash engaging means in the frame mounting member as the stay is closed, with the distance between the upper arm - sash mounting member pivot joint and said frame engaging means on the end of the sash mounting member being less than two thirds of the length of upper arm between pivot joint centres to lock the head of the stay against forced opening.

3. A window stay as claimed in claim 2, wherein the frame engaging means comprises a protrusion from the end of the sash mounting member and the sash engaging means comprises a recess to receive said protrusion, the protrusion being arranged to engage into the recess as the stay reaches its fully closed position.

4. A window stay as claimed in claim 3, wherein the protrusion on the end of the sash mounting member has a land on the side of the protrusion opposite the offset pivot joint which land slopes downwardly away from the end of the sash mounting member, and the recess on the frame mounting member has a complementary land on the side of the recess opposite the offset pivot joint which land similarly slopes downwardly away from the end of the frame mounting member.

5. A window stay as claimed in any one of claims 1 to 4, wherein the distance between the upper arm - sash mounting member pivot joint and said frame engaging means is not more than one half of the length of the upper arm.

6. A window stay as claimed in any one of claims 1 to 5, wherein the length of the upper arm between pivot joint centres is between one half and the three quarters of the length of the lower arm between pivot joint centres.

7. A window stay as claimed in any one of claims 1 to 6, wherein said angle between the upper arm and the sash mounting member when the stay is closed in between 13 and 20 degrees.

8. A window stay as claimed in any one of claims 1 to 6, wherein said angle between the upper arm and the sash mounting member when the stay is closed is about 15 degrees.

9. A window stay as claimed in any one of claims 1 to 8, wherein the offset pivot joint is offset from said line passing substantially through the other pivot joints by between 10 and 40 mm, measured between said line and the centre of the offset pivot joint.

10. A window stay as claimed in any one of claims 1 to 8, wherein the offset joint is offset from said line passing substantially through the other pivot joints by between 15 and 30 mm, measured between said line and the centre of the offset pivot joint.

11. A window stay as claimed in any one of claims 1 to 10, wherein the frame mounting member is formed of a plastics material and the pivot joints between the frame mounting member and each of the arms of the stay have a hollow centre to allow screws for fixing the stay to a window frame to be screwed through the pivot joints.

12. A window stay as claimed in any one of claims 1 to 11, wherein the frame mounting member is formed of a plastics material and the pivot joints between the frame mounting member and each of the arms of the stay comprise an annular shoulder of the plastic material of the body of the frame mounting member projecting from the frame mounting member, an aperture in the arm whereby the arm is located for pivotal movement about the shoulder, and a fixing means for fixing the joint and applying friction creating pressure thereto extending through the joint and fixed within the shoulder and/or within an aperture in a frame mounting member below the shoulder, with plastics material extending from the shoulder between the arm and fixing means to prevent direct contact therebetween.

13. A window stay as claimed in claim 12, wherein the annular shoulder prior to locating of the arm about the shoulder and insertion of the fixing means comprises a first annular part projecting from the frame mounting member of greater wall thickness and a second annular part above the first part of reduced wall thickness, said second part having been bent over to lie between the fixing means and the arm to prevent direct contact therebetween during insertion of the fixing means.

14. A window stay as claimed in either one of claims 12 and 13, wherein the fixing means is fixed within the shoulder by self-tapping screwing into the plastics material within the annular shoulder and/or an aperture in the frame mounting member below the shoulder.

15. A window stay as claimed in any one of claims 12 to 14, wherein the sash mounting member is also formed of a plastics material and the pivot joints between the sash mounting member and the arms of the stay each comprises a pivot joint of the construction defined in any one of claims 12 to 14 for the frame mounting member - arms pivot joints.