Note: Descriptions are shown in the official language in which they were submitted.
s~7320
.
04~S~3
q?he pr~s~nt in~ention relat~s to Venetian blind~.
~ho s~at~ o~ a wand operat~d Venetian blind a:re ti~ted by
manu~lly rotating a ~and~ al~o called ~ baton, The ~and~
rotati~ely dr1vos b~o worm o~ a worm and-~ssar til~er. Th~
5 worm rotate~ tho gsar and~ b~ ~uitable and known means" tho
movemsnt o~ the gear i~ tr~nsmittad to ths ladders and
rend~red e~c1;i~e to tilt the ~lat~ o~ the blind bg~ pulling
up the rear ~idapiece~ Or the ladders while payi~8 out ths
~ront sidepieces9 or vice ~tr8a. -
Continued t~lt~x~ o~ the slat~ clo~e3 the bl$nd to ita
maximum normal ¢lo~ure~ ~he point o~ maximum rlormal oloslu~e~
in ths usu~l Venetlan blindOis reaohed b0~0re the ~dge o~ e~h
~l~t Would move agsin~t tho ~ao~ o~ an adJaoent ~lat~ the li~b
cords inter~ere with ~uoh rull alosure exoept ~n the oase ~P
1~ a so-called ~ull olo~ure bl~nd 3uch as, ~or example~ blind
disclosed ln U.S. Pat~n~ 3,170,505. When the polnt o~ n~clmum
norm~l 01091~e h~L9 b~en rsach~d ths porson olo~in~ the blind
ordln~rily halts hi~ rotabion o~ the wand. Xowe~ri a per~on
ma~ ~all to timely halt ~1~ rotation o~ the wand; he may be
inattent~v0, or he may ~%ppose th~t he oan olose th~ blind
atill morfl by continued rotatlon o~ the wandO
When the point or maxim~n norm~l 0l09UI`e h~s bee~
reached, continued rotatlon o~ the wA~d oause~ overpull on
khe ladd~rs; alld th~ overpull oan b~oome d~leterlo~ ln one
or moro ways. ~ho o~erpull may ~amb th~ top slat ~ga~n~t the ~ -
head o~ the blind~ ~1SOJ it may ~-use the top slAt to Xlip
o~er or try toJ particularly in the oass o~ a narrow slat
bl~nd. In tho oase Or the bl~nd o~ U~S~ P~ten~ 3~?~g~237J in
wh~oh the top slat ooac~s ~lth a cord-loc~ actuator5 it i~
po~ble ~or ovorpull on the ladder~ to roul ~he oord lock.
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~ 049~5Z3
In any cas~ excesslv3 oonti~u~d rotat~on o~ tho ~and ~ter
the bl~nd has r~aehed it9 ma~imNm normal clo~ure can oau~e
excesslve ten~ion to be exerted on ~idapie~ses of the ladder~
and/or o~ ~ho~e rung~ o~ the ladders which are draw~ng tho
top slat ag~ln9t the bottom Or the head Gh~mnel~
The gear oP th~ tilter i~ a sector o~ le9s than 360
~ogrees, ~hereby tho gear can run out ~ me~h with ths ~orm,
AppliGant~ construction and arrangement are such thst~ wh~n
maximum normal 0109ure 0~ the blind ha8 been reached~ the
gear 1~ on the verg~ o~ running ou~ o~ me9h with the worm
--meanln8 that 8mall additlonal mo~emsnt o~ thc ge~r would
oaW e the gear to run ou~ Or mesh with the worm. Ab thi3
point the per~on clo~lng the blind would normally halt hls
rot~tion o~ the wand, 8hould he ~ail to do 80, the gear will
1~ promptly run out o~ mo9h with the worm to ~u~p~nd biltlng
aotion o~ the ~ilt~r bo~ore deleteriou~ o~erpull on the
ladd~rs ha~ taken plaae~ Continued rotation Or th~ wand wlll
then be i~er~eotiva~ and w~ll bo harml~ss aaoording~y.
Many~ psrhap~ mos~l Veneti~n blind~ are arranged to b~
clo9ed by tilbing the 81at9 ln either direotion, If the
bllnd bs on~ whloh 1~ arranBed ~or 0109ure ln either direo~ion
tho tilter ~ill provid0> as regards ~oh diractionO ~or the
~sar runnin~ out o~ mesh w~th the worm unle~s rotatlon o~ the
wa~d i9 halt~d prompt~y upon the m~x~mum normRl clo9ure o~ :~
2~ ~he blind being reaohed~ Il bhe blind be one ~hioh ~8 .
arranged ~or olosure ~n one direotion only, the t~lter need
provide~ a~ reg~rd~ that direotion only~ ~or the Be~r runnlng
out Or mesh with ~he worm~ .
Th2 ~l~tg 0~ th9 b~ind are tilted to olosed position b~
pulling up either ths ~ront or the rear ~idep~eces ~ t~e
~3-
~4~
S'~3
ladders, !rhe pull on the sidep~eces ~nean~ that thsrQ i~ baok
pull by k~e 3idepisces ~hem~elves~ as~l thi~l back pull i~
rairl~ atrong a~ the blind appro~ohes maxi~ ormal 0103ure.
~he back p~ll i8 ~ran~mitted to the tiltor and b~aa~ the
5 ge~r retrogres~lvelg. q~he e~d ~ooth o:e th~ ge~r havi~g rur
out o~ m~sh with the worm, and the thre~d of` tha wo~m ha~rlng
~lipped past the ~nd tooth~ the r~l;rogre~sive bia~ ~ the
gear eauses the gear to retrogre~s a little ~-the r~trogrs~-
~on belng Rrrestsd bg the end tooth o~ the gear ~ec~or
ongag~ng the worm convclu~ion somewhat back of ths poink ~t
whiah the tooth ran out o~ mesh with the worm, To pre~ent,
or at lea~t limit~ retrogres~lon o~ the blind ~rom maximum
norm~l olo~ure~ ~he polnt a~ ~hioh the go~r 1~ ~o run out o~
me~h with tho worm i8 plaoed 30mewhat be~ond th~ poSnt ~t
1~ ~hiah ma~lmum ~ormal olo~ure Or the blind i8 r~ached~ ~h~reby
~11 or some o~ the re~rogression o~ tha gear will h~ve tak~n
plaoe be~ore the geQr has retrogres~od to the point at whi¢h
maximum norm~l clo~ure o~ the blind was reaahed.
The invention i9 lllustrated, by wa~ o~ example in
2~ ths ao~ompan~ing drawing~ in whioh:
~ ig~ ~ 15 ~ largoly dlagrammatio rront alevat~o~ o~ a
Vsnetia~ blind e~bodging th~ inventio~, the ~ront~ o~ the
blind boin~ the ~ace thQt 18 toward tho room~
FiB. 2 i8 09gentially A ~ront elevation o~ a ~ragment
of the head a~ tha blind~ on a larger s~ale~ a por~ion o~ ~ho
~ronb ~all Or the head ohann~l beinB broke~ out to roY~al the
tiltsrj
~ 1~. 3 19 es~nt~ally a seotion Or the he~d~ ta~en
~nerall~ on the Dine 3~3 Or Flg, 2. ~ rragment ~r the
~~
.. . . . . . . . . . . . . . . .
. . . .. . . .......... .. .
. ~
-5~
11)4~5Z3
l~ddor-and-slat a~3emb1~ i~ lndlc~tod includi~ a ~r~gm~nk
0~ B l~t oord, Th~ blind iq ~ully open, the ~lat~ belng
horizontal~ i.e. untllted.
Fi~ 4 i~ the sam~ as Fig. 3 but with the blind and
t~lter ~t the poinb o~ maximum normal olo~ure with ~h~ ~lats
tilted forwardly, l.e~ tilted with ~he ~ro~t edge~ Or th~
31at~ dspre~3ed~
Fig~ 5 is ~he 3am~ a~ Fig~ 3 but with the blind a~d
tilter at ~he polnt Or maximum norm~l closure ~ith the ~lats
tilted rearwardly, i.e~ tilted with th~ rear edge~ o~ the
slats depre~ sed .
The drawi~g ~hows the presently pro~err~d embodiment o~
tho invention~ i.e~ the bes~ mode thu~ rar contomplated o~
o~rr~ing out tho inven~lon. Exoep~ a~ m~y ba otherwi~e
lndioated, the descriptlo~ herelnart~r re~ers on~y to the
particular smbodiment o~ the in~ention that i9 sho~n ln the
dra~ing, ~everthele~s~ the disclosure is by ~ay of illus~
tration and example; the olaim~ ombraoe other embodiment~ ~
o~ th~ invention~ : :
Except ~or the t~lter and the ooordlnation o~ the tilter
with khe ladders~ both Or whioh will be de3crib~d and explnin~
~d laterJ the blind m~y be a wand operated Yenetl~n blind o~
suikable known ~on~truction and ~rran~ementJ ~or ~xample, th~
oonstrustion and arraneement dlsolos~d in t~e U.S. patent e~ ;
~orent~en et ~1 3~425~47g 19su~d Fsbruary 4D 1969. ~h~ known
oon~truction and arran8ement th~ i8 disclosed in the pre~e~
application i~ the constructlon and ~rrangement Or the blind
o~ that patentO
~ ladder~and-~lat a3sembl~ that i3 d~signated ~
whole by 15 i8 po~ition~d bsneath a head whioh i9 de3ign~tod
,.. ... . . . , . . . `,. ,. .. , . . .. ;.. . .. , .. . . ~ ;;
104~S23
a~ a whole by 16~ m e ladd~r~and~ t ~s~embly include~ 8
s9rie~ 0~ 91at9 ~7 that ar~ ~upported and arti¢ul~t~d together
ln known manner by two or more ladders 1~. Eaoh ladder 18
ha~ a Pront ~idepie~e 18a and ~ rear ~idepiece 18b, the ~wo
~idep~eoe~ being interconne¢ted by v~rtically-~pao0d cro~s- :
pieces or rungs ~ôc on which the slat~ 17 re~t, The l~dder
shown i5 0~ the ~trin3~l type~ the sidep~oes 18~ and 18b
being braided cords and each ¢ro~splece l~Q belng a plural~t~
Or ~ilaments whlch may b~ braided or twisted int~ one or more
strands~.
The head 16 ¢on~ists primarily o~ a sheet-steel ohannel
20 and the me¢hanism that i9 oontalned therelnO ~he ohannel
20 has a ~ront wall ~Oa~ ~ r~ar wall 20b and ~ bot~m wall
202. A~ong the upper ed~s o~ the ~ront and rear wall3 20~
1~ and 20b there are long~udinally-extendlng ~langeY 20d wh~oh
~re ~olded lnwardly and downwardly. The bottom wall 20c 18
piero~d in known m~nner (not shown) ~or pa~sage lnto the
oh~nnel 20 o~ eaah sidep~ec0 18a and lôb Or the ladders and ~ .
o~¢h ll~t cord 22 (one ~ho~n~.
~he Venetian blind~ designated a3 a ~hole by 14 in
F18~ 1~ i3 ~hown diagr~mm~tlaall~ a~ bein8 mounted in
oon~entional manner with~ a windo~ opaning. The head 16 o~
~h~ blind i8 mounted on co~vent~on~l ln~tallation braokets
one atkaohed ~o each o~ ~he ~amb~ 6 o~ the ~indow openlng.
~ha ~o~ o~ ~he ~lndow op~nlng ~9 indioated at 7 a~d ~he
sill at 6.
~he construc~lon~ arra~gament and operation o~ the
tilker ~ill now be d~cribed. The tilter~ ~hieh i9 de~ na~ed
as a whole by 40~ 1 w lude~ a hou~lng bhat i8 mounted in the
head ehannel 20~ Journalled within ~he housin5 the~e i~
~6_
.. . , . ~ ., ,. ~ , - ,
1~4~5Z3
doubls threa~ ~orm 41 and a gaar 420 ~he ~orm i~ m~ld0d in
one pleco wi~h a ~h~t 45 that proJ~cts as sho~n through an
op~nin~ 20~ in the head ~annel, ~h~ch ope~ing i8 ~pread
over an area that in¢ludes th~ ~un¢ture o~ the ~ront wall
5 20a and the bottom wall 20c, Hanging down ln ~ront oP the
l~dder-and~lat assembly 1~ )J ~nd ~uitably conne¢ted
to ~he worm ~ha~t 45~ there i~ a ~Qn~ 38 which i~ manuall~
rota~ed to rotat~vely drivs the worm 41-
~he wand 38 Qnd ita connection tQ sh~t 45 m~ be aa in
U.~. Patent 3~425~479. Except ~or the gear 42~ t~ coordina~
ti~n Or the gear 42 ~ith the worm 41 sn~ the coordi~ation o~
tho gear 42 with the l~dders ~8~ the tilter 40 and its
mountine in the head ohan~ol 20 are the ~ame a~ ln U,.S.
Paben~ 3,425~479. Fig~ 3 shows the r~l~tion~hip between the
15 worm 1~1 and l;he gear 1~2 when the gear '~g in mld positio~,~9" hal~-way between its llmlt o~ rotati~n ~lockurlse and
itd limlt o~ rotation ount~r-clockwi~. lL9 a Dlatter of
m~chaIlioal oonveniancs in the partioular tilt~r, Q radius o~ ~:
~e gear 42 doe~n~t ~n~ers~¢t the worm hal~way between the
20 ends o~ th~ worm 41 bu~ lnterseGt~ the ~orm nearer the top
end o~ ~he worm,
;ear 42 1~ a seotor o~ le~ then 360 de~ree~9 the . .
partioular gear shown bsing a ~eator which i8 8/13 Or 36~ ~
dagrees. The gear 1~ driven b~ the worm; and rotation o~ th0 ~ ::
g~ar in ei~er dircct~on 1~ limited b~ the ~ ooth o~ the ~:
gear s~ctor boing brought to th~ worm and then pu~hed as ~Pr
as the ~orm can push ~t. F~g. 4 shows the relatlonship
between the worm 41 a~ the gear 42 when the gear i~ on th~ :
ve~ge o~ run~ing out ~ me~h wlth khe worm b~ olockwi~e
~o rotab~o~ Fig~ ~ shows the relRtionship between the ~a~m 41
q7~
104~SZ3
and the B~a~ 42 livh0n the ~ear i8 Otl the verge o~ r~ning out
of mesh with the ~orm b~ oount0r-olookwise rotat~or~0
Tho construot~on ar~ arrangemexlt o~ the blind o~
Patent 3,425,479 is used in ~he pre~ent in~ltanos to transmit
the m~ement o~ bhe gear 42 to the ladders 1~ and ronder the
~ nt Or tho ge~r e~ect~ve to tilt the slats 17 by
pulllng up the rront sldep~eoais 18a while paging out ~e
rear ~id~plsc0s 18b or vlcie ~ersa, ~g in the bllnd o~ ~.S.
~tent 39425,479, the gear 42 i3 ooaxial wlth a st3el tllt -~
rod 24 o~ D-shaped cro~s ~ectlon~ whlch rod i8 al90 oalled a
D rod. The rod 24 makes a sliding ~it with a D~shaped holo
24~ in the hub Or tho gear 42J and the rod extend~ aorossi
the tops Or the ladder~ 15, At the ladder~ the til~ rod 21~ .-.
oarrie~ drun~ (nob shown) to which th~ sid~pleoes l~a and
15 18b Or tho ladder~ are 3uitablg attaahed, e.g~ a~ di~closed
in U.S~ Patent 3~425~479.
~ n increment o~ angular movement o¢ the Be~r 42 doa~n~t
erreot a particular lnor~m~nt Or tllting mo~ment o~ the
~lat~ ~7 regardlass Or the mean~ by whioh the mo~ement o~
th~ eoar i~ tr~nsmitted to the clst~ or regar~le~s o~ the
widbh o~ the 31a~c. What an inorcmen~ of ~ngular movemont
o~ the ~ear 42 doo~ do ~3 to o~ct a ~lke inorem~t Or
~ngular mov0m~nt o~ the tllt rod 24 and ths ~run~ that are
~ounted thereon and ~o ~hioh the ladder sid~pieGe~ 18a and
2~ 18~ are ~ttached. How muoh th~ sidepieces Or the ladders ~re
ral~ed or lowered b~ a glven increment o~ angular ~o~ement
~ the drum~ ~ill be eoYe~ned by th0 radiu~ o~ the drum~0
~nd ho~ much the ~lats are tl~d by a partlcular Sncrem~n~
of up anâ do~?n mo~omen~ o~ the sid~pleces 18a and 18b ~rill
~0 be e.~ecte~ b~ tho distance ~e~een th~ b~o siaepiece~ Or
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~9--
~4~1523
a laddcr ~hieh~ in turn~ is go~ern~d b~ ~he width o~ th~
slats~ ~he net re~ult i~ that the ~ear s~otor 42 should be
ooordi~ated with the slats for th~ particular b~ind in ~hich
the tllt~r i9 to be u3ad.
In tha blind ~ U.S. Pate~k 3~425,459 the drum~ to whlch
~he laddor~ are ~ttaeh~d ar~ in m~d positlon~ and the slat~
are untilted as shown ln Fi~, 3 o~ the pressnt application,
whon the rl~t of th~ ~-rod 24 i~ hori~ontal and i9 at the
top~ ~ith the gear ~eCtQr 42 in the mid rokative positlo~
~0 ~ho~n ln Fig. 3J the n~oe3~ary rotat~e lndexing o~ ~he
~-hole 24~ i~ the hub o~ the eear ~2 can be e~tablished~
the holo 24t ~ill be rotativel~ indsxed ~o plac~ the flat
o~ the hole 24~ horizontal and on top when the drun3 are
.. ..
in mid po~ition and the ~lat~ are untilted. ~hen the teeth . . .
Or the gear sector 42 oan be layed out. Tho oir¢ular pitoh ~:
of the teeth and the number on ea¢h side o~ the mid point a~e
~ele¢ted to have the gear on the v~rg~ of runnlng out Or m3sh
with the ~orm wh~n the 31at8 ~7 have been tilted ~o bhe po~nt
Or maximum norm~,l olo~ure o~ the blind~
In the pre~ent oase the gear ha9 eight teeth snd th~ :
eighb keebh take up 8 h3 ~ th~ o~roumrerenoe o~ ~he goar
42. Tha numbcr o~ teeth being e~en~ khe ~eotor ha~ a ¢en~er
p~ir Or teeth ratb,er tha,n a oenter tooth. I~ Fig~ 3 the
~ eenter pair o~ teeth o~ the gear 42 13 in, mesh with the
~orm 41. Prooeedi~g counter-olock~i~e ~rom the center palr
o~ beeth~ the ~e~itor 18 pro~ded wlth ~hr~e teeth ~he end
tooth Or which i9 ~ooth tl~ ~roc~edlng clookwiss ~rom the
~enter pair o~ teeth th~ g~ar ~eetor 42 lg provided ~ith
three teebh the end too~h Or which i8 ti2e Rot~bing ~h3 wan~
.. ~9~
~10- :
~ 5Z 3
ln tho direotion of the arrow in F~e. 4, the end to~th tl i8
brought to the ~orm 41 and i~ on the verg0 o~ running out
o~ m~sh wi~h the worm ~hen the blind has b~en brou~h~ to it~
maximum ~orm~l cl~ure by tilting the ~lat~3 forwardly; this
i8 8hown in ~ig. 4~ Rotatlng ~he wand ln khe direction o~
the arro~ in Fig. 5~ the end tooth t2 i9 brought to the
worm 41 and i8 on the Yerge Or ru~ning out Or m~sh with the
~orm when the bllnd has been broughb to its mR~mum normal
clo~ure by tiltlng the slats rearwardl~; this iq shown i~
Flg- 5~
Onco m~ximum normal clo~ure h~s ~esn reached in either
dlrectlon, bhe ~ear 42 wlll run out Or m~sh ~ith bho worm 41
unless rotabion Or the w~nd 38 19 halted promptly, .~owe~er~
R llttle addltional rotation o~ the ~ear 42 ~g rsquired ~o
cause the gear to run out o~ ~sh with tho worm, When the
8ea~ doos run out e~ m~h with the wor~, the gear will
retrogre~ a littl~ a~ ha~ been explained. ~ut unle~a the -~
rstr4gress~0n bri~g~ the g~ar ~arther b~ck ~han the point
~t which ma~imum n4rmal 0109Ure ~a~ reached, bhcre will b~
no retrogre~sion o~ th~ blind ~rom maximum normal closure~
The retrogre~aion o~ the blind ~rom maximum normal clo8u~e
i9 llnited accordingly and may be oomplet~l~ ob~iated~
Pre~a~ably ea~h end too~h ~l and t2 i po~itioned to keep
the ge~r ln mesh ~ith the ~orm 41 untll tha angle by ~hlch
the gear has passed the point at which maxlmum norm~l
clo~ure ~as reached i3 at lea~t as gre~t as the m~ximum
~n8le o~ retrogrea~ion o~ the ~ear ~hen the g~ar runs o~lt
o~ mesh ~lth the worm~ Thi3 in~ure~ that there ~lll be no
rotrogre~s~on o~ the blind ~rom m~xfmum normal 4109Ure w~en
the Bear runs out of meah ~ith th~ worm~
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~ 4 ~ 5 Z3
It ~111 bs s0en that the blind i3 ~utomatically
prot0~ted ag~in~t the po~9i~11ity 0~ deleteriou~ overpull - :
on the ladders by oontinued rotation of ~h~ wand a~ter
maximu~ norn~l closure ha~ ~een reaohed~ Xt ~ill al~o be
seen that re$rogre~ion o~ the blind rrom n~ximu~ normal ~ .
closure i9 limited and~ pre~erably, obviated.
In the blind of u.æ . ~atent 2 ~174, 991~ the ~eQr Gan
rwn out o~ ~e~h with ~ho ~orm at times. Th~ worm 13 ~otated ~ :
by ~ ~ord~driven pulley and the gear i8 to ~un out o~ me~h
w~th the worm o~ly when aooumul~t0d ~lippage o~ the ~ord on
the pulley-i~ to be correot~d~
" :,..-"'
