Note: Descriptions are shown in the official language in which they were submitted.
~a~
THE S PECIFICATION
This in~!ention relates to a leg leveling mechanism and
novel co~nbinations thereof with various leOged machines and
s tructures .
CKC~R OUND T 0 T~E INVE11TI()N
Prior to the present invention there have existe~ various
. leg-leveling devices such as ~or example are shown in U.S. ,-'Patent No. lJ7l9gL135 to Lowther in which for a leg b,iased
downwardly there is apertured strip slipped arouncl the leg
and anchored at one end such that upper pressure of the
spring on the under face of the aperture strip serves to
cause the strip to be angularly inclined relative to the ~'-
vertical downwardly extending shaft of the leg to thereby ,
bir.d the leg shaft a~ainst further axial movement, the axial `
adjustment being rnade by depressing the free end of the strip
':' ,
., to prevent the binding thereof; such a device is dependent ;
solely upon a very minor degree of frictional binding at
each of extreme opposite small surfaces on opposite sides Or ',; ~ '
the aperture against corresponding circumferential surfaces
of the leg shaft and would be totally inadequate for a ''
rnachinery apparatus of any substantial weight or vibrations,
as well as any apparatus in which substantial jarring of the
leg shaf`t might take place to dislodge the minor degree of
b:inding on the shaft thereof~ Also/ for such a mechanistl1 as
of this noted patent, there is required to be a separate lever
fo~ each leg such that it is substantiall~ impossible to
concurrently adjust all legs at the same time simultaneously,
wlth the result that it is s'Gill very probable that lt~hen
each leg is separat;ely ad~usted t~lat the plurality of ~.egs
considered togethcr are still not in proper alignment for an
.
- 2 - ;
.~ . ' ~ ....
7~ 2
equdl we~ght distribution o~ th~ appar~tus or machine belng
balanced, particularly where a mdchine is involved irl which it
will have s~bstantial vlbration during the operation thereof
where totally accurate balancing equally o~ all legs is
essential. In like manner, the U.S. Patent No. 1,224,156 to
Ferrito discloses a downwardly-biased leg shaft having
notches in its lateral face en~ged by a pawl by virtue of
a small spring biased against a pivoted lever arm, lt being
noted that moreover it is essential for this patent that khe
button end of the lever arm being pressed laterally inwardly
to release the leg shaft for a leveling thereof such that it
would be impossible operatively for the biasing spring
against the lever to be of any substantial strength because
. ~ .
if that were the case it would not be possible for a person
to push the button of the lever inwardly to release the
button from engagement with the notch along the leg shaft; ;-
accvrding~r~ SUCh a de~rice as sho~^7n in this patQnt'~lQ.~l~y
would not be applicable nor suitable ~or any heavy article
or m~chine, particularly where a major degree of vibrations
would be encountered. Also such a device of this U.S.
Patent No. 1,224,156 could not suitably be utilized for
simult~neously adjustment of a plurality of legs as is
preferable and essenti~l for complete and accurate ~eight
ad~ustment equally on all legs.
The need ~or a good and reliable sturdy leveling device
for a plurality of legs is particul~rly notorious for each
of washing mdchines and other similar type machines subject
to vibrdtions of a large magnitude, and notorious for step
ladders, step lddders being the sub~ect matters of mlny
~ccidents and severe inJuries to persons using them because
.
~ 3 ~
7~;~
of improper balancing of the legs, pdrtlcularly where the
surface i5 inclined, stepped, or the like.
SUr~RY OF T~ INV~NTION
Accordingly, objects of the present invention are to
overcome one or more disadvantages and short-comings and
difficulties of prior devices and to meet the needs of the
types discussed above.
Another object is to provide a novel locking and latch~
ing and release mechanism for a plurality of legs to be
leveled concurrently.
Another object is to obtain an improved slanting device -~
- for a semi-autom~tic leg leveling device.
Another ob~ect is to obtain a high-pressure lever device
for applying a high magnitude of clamping force against a -
clamping structure independent of variations in length of ~ -
.
pressure~applying levers for different legs commonly
operated by a common pressure applying and pressure releasing ~ ~
latching device. ~ -
Another object is to obtain alternate-length legs for -
differing levels. ,
other ob~ects become apparent from the preceding and
following disclosure. ;
one or more obJects of the invention are obtained by the
invention as defined herein.
Broadly the invention mdy be defined as a combination of
elements for applying a locking pressure against a locking
surface including dS d part of the elements opposed elements
biased apart by an intermediate spring but with limiting `~
~ructures llmiting the distance th~t the opposed parts r~y
be biased away from one another such that the entire combina-
, . ..................... .
- 4 -
'
`
7~
tlon mdy be l~ithdrawn from contact with a sur~ce to be
pressed to thereby totllly relelse the pressure thereon,
on the other hand when in a pressed state the exact ~novernent
Or the combin tion of spaced apart dnd spring elements
towlrds the surface to be pressed and/or the exact length `;
Or the elements sp~ced ap~rt being immaterial in so far as
a constdnk strong pressure bec~use o~ the latter.
THE FIG-JRES_
Figure 1 illustrates a typical embodiment and the
mechanism thereoL o~ a leg leveling device of the present
invention, illustrated in side in-part cross-sectiOnal view.
Figure lA illustrates a bottom plan view in crOss-section
through tlle leg being leveled and in partial cut-away, o~ a
preferred embodiment of the invention in-part view
Figure 2 illustrates an elevation bottom plan view of a
large article or machine having ~our legs at each of four
oppvsite corne~s, illust~ating ln an i..-~_rt ~J~ew the ^entral
mechanism o~ common actuation o~ each of the separate
- pressure levers ~or the individual legs, and illustrating
also in partial cut-away one particular leg.
Figure 3 illustrates an enlarged view in cross-section of
a portion Or the Figure 2 illustration, illustrating in side
cross sectional view the mec~nism o~ a releasable pressure-
locked structure.
Figure 4 illustrates a side view in cross-sectiOn through
a lever o~ Figure 3 as taken along line 4-4 of Figure 3, and
an elevation plan view of the notched surface eng1ged by the
lever end.
Figure 5 illustrates a side perspec~ive view of a typical
step ladder embodiment, detach~ble legs-leveling device
~ 5 -
. . . . .
mounted thereon.
Figures 6, 6A and 6B illustrate in-part diagrammatir
elevation plan views of pressure-applying and releasing latching
` mechanism for oppositely extending lever arms such as of Figure 5, ^
Figure 6A being a cross-sectional view through the actuating lever,
in an unlocked state, while Figure 6B illustrates the same in a locked i~
state position.
Figure 7 illustrates a side view in partial cross-section ;
of the latching lever in its unlocked state. ;
Figure 8 lllustrates portlon 13 of Figure 5 embodiment,
and a clamp of Figure lA. "~!'
- Figure 9 illustrates a view in partial cross-section '
;: : ': -
through the adjustable leg and through the step ladder leg,
in bottom plan view as taken along lines 9-9 of Figure 8.
Figure 10 illustrates in side view partial cut-away and
partial cross-section, diagramatically an alternate the locking `
lever arm lockable on top of the support structure. Figure 10
is a preferred embodiment of the ladder of Figure 5.
Figure 11 illustrates an in-part view in partial cut-away
as taken along lines 11-11 of Figure 10.
Figure 12 illustrates an in-part view in cross-section `;
as taken along lines 12-12 of Figure 10. `~
Figure 13A and 13B illustrate in-part views in side per-
spective, of an alternate embodiment in which the adjustable
leg has a detachable telescoping shaft, Figure 12A being shown
in exploded view.
Figure 14 is an in-part view in cross-section as taken
~` along lines 14-14 of Figure 13B.
!"
Figure 15 is a cross-sectional view along lines 15-15
of Figure 14.
DETAILED DESCRIPTION OF_THE INVENTION
~ith particular reference to Figure 1, there is disclosed
..
~1
.:
~ - 6 -
, . " ~. . .
. .
a typ1cal leg-leveling devlce 10. Figure lA illustrates a
bottorn-pl~n view of an alter,l~te embodiment lOA while
Figure 2 illustrates a still other alternate embodiment lOB.
For the leg lev~ling combination lOB there is included a
circumscribed portion 11 as vie~led in elevation bottom plan
view, which circumscribed portion of the bottom of a machine
- and the outw~rdly extending leg thereof in conJunction with
the leveling structure of the present invention are shown ~s ~-
~ an enlarged view in cross~section in Figure 3. The enlarged ~ :~
.- 10 circumscribed portion 11 is also illustrated in ~igure 4 as
taken along line 4-4 of Figure 3, and Figure 3 is an actual
cross-sectional view as taken along lines 3-3 o~ Figure 4.
Figure 5 shows a step ladder combination 12 embodying the
, leveling device as a latched~on portion thereof.
.- ' Figure 6 illustrates a diagramm~tic view of the pressurlz-
ing and pressure-releasing latching lever structures in
enlarged in-~ r~, çleuation pl.~n view as wo~ be view ~r
, the step ladder combination 12. The diagrammatic structures
. illustrated in each of Figures 6A and 6B are further dia- -
' 20 grammatically illustrated in Figure 7. .;
1 The Figure 7 illustration is of the pedal mech~nism 14
-J identified broadly in Figure 5.
, The Figure 8 illustrates a portlon 13 circumscribed a,s a
'. part of the Figure 5 embodiment,
'~ Figure 9 illustr~tes a view o~ the same portion 13 as
'~ viewed on lines 9-9 of the Figure 8. As might be readlly
:
seen by the v:Lew of Figure 9, the portion 13 of the step
ladder combination 12 embodiment corresponds substanti~lly in
~ an appearance of embodiment o~ Figure lA, structure 10~, and
;, 30 accordingly the structure lOA corresponds in its respective
,.
~ 7~
:
side yiew substantially to the appearance of the portion 13 oE the
Figure 8.
In greater details, there is illustrated in Figure 1 a
slidably mounted leg shaft 15 extending uprlghtly along its longitu- .
dinal axis of the shaft thereof anchored within the slide space by a ~ .
threaded ~olt 16 and biased outwardly ~y coil springs 17 within the : .
space-defining enclosure structure 18. A leg shaft 15 has a scored or
notched or toothed or otherwise uneven face 19 against which a locking
key 22 is biased by a spring 25 and shaft 24 is in a locked position, -~ ~
this relationship shown in greater details in an alternate embodiment :;
of Figure 2, 3 and 4 particularly with reference to the Figure 3 illus- .
tration described subsequently below. Rubber padding 21 is mounted on
the flange foot structure 20. The arm 27 is mounted substantially
flushly but slidably within the brackets 26A and 26B and includes a
pivot pin 28 linking it with the link element 29. Link element 29 has .-
a key 30 locked pressably against the end wall of a slot 31 of pivoted ;;.~.
lever 32 pivotably mounted by a pivot pin 32' on a support 34. Key 30 ..
is on upwardly and downwardly slidable structure 33', which structure . `~
is in turn mounted around upright pin 33. Key 30 is pressed into the
illustrated locked position, which action causes locking key 22 to ;.
bring pressure against:leg 15 by pressing downwardly on pedal 37 against
action of the biasing spring 36 connected between the lever 32 and the :.. .
.. : .
bottom support plate 35 of the structure supported by the leg shafts .~
. 15, the bottom plate 35 typically being the bottom plate of a washing .;
machine or of a stove or the like. This operation is perhaps more clearly
described and illustrated subsequently, with respect to a similar struc- :.. ;. ture of Figure 10.
Figure lA represents an embodiment basically similar to ~
that of Figure 1 in its construction, except being an in part ;~
yiew in elevation plan view of an alternate embodiment in .. .:
which a leg structure 41 is shown in cross-section as bound
or clamped between machine anchored structure 40 and the
- 8 -
,. ~ :
,. ~, ;
.7~
movable clamplng structure 39 mounted by plvot pln 3~.
Pressure seat l9a is illustrated in cut-away cross-sectional
view to illustrate the pressure contact of the end of the
pressure lever key 22a shown also in an in-part view.
Figure 2 illustrates typically a bottom plan view of a
'~ washing machine lOb with the bottom plate ~5d having a
plurality of rnounting structures 40d mounted on the respec-
tive four cOrners of the plate 35b all actuated by respec~
; tive lever 27bj 27b', 27bl1 and 27b ~, each anchored onto
radially extending flanged 42 mounted pivotable around
central pin 41 and moved rotatably there around by action of
the lever 27c which corresponds typically to the lever 27 of
the Figure 1 embodiment, other actuating mechanisms being ''characteristically the same as that as shown in Figure 1
such as the link 29 and the lever 32 and the ~oot pedal 37, - ,,
and the like. The support leg of 15b is shown in cross-
sec~ional cu~ wav ~r a be~ter illustra~ion, and the
- ' relationship of the portion of phantom circle 3 is shown in
- cross-section of Figure 3 illustrating an alternate embodiment to
,that- of Figure 1J in which the spring pressurizing release
- structure and mechanism 11 is shown to be mounted fixedly on
the legs structure 15b itsel~ with the toothed or notched ;"surface l9b being located on a ~lange 23c extending out~ardl~
~rom the structure 23b. The key 22b when under pressure is
pressed lock~bly into the recesses o~ the teeth or notches
l9b as shown in greater detail in Figure 4, as locking is ~-
applied to the lever 27blt. When the key 22b is pressed
into its locking pos~tion and state within the notches l9b,
the spring 25 is compressed to thereby exert ~ull pressure
against the leg 15 to thereby preventing furthér upward or
' ' .
_ g ~ ~:
,.
. . .
:, ; "~
downward sli~ble movement of the leg in the manner as ,,
shown ln the Flgure 1. When' pressure is relieved ~rom the
lever 27b " such as to withdraw the key 22b from the notches 'i
l9b, the flanges 23d and 23e respectively become engaged
thereby preventing expansion o~ the spring 25b such that
the notches 19b of flanges 23c do not ~ollow the key 22b ,
upon withdra~7al of the lever 27b~1, whereby the structure
of notches l9b o~ 23c becomes disengaged from the key 22b . "
thereb~ preventing the leg 15b to again move upwardly or
downwardly in axial directions of its longitudinal axis '. ~.
within its sleeve in the same manner as illustrated ~or ~,
Figure 1 that the leg 15 moves along its sha~t's longitudinal
axis dlrection within its sleeve 1~,
Figure 5 illustrates the stepped ladder embodiment 12
having the stepped structure 43 and the supports 41c and
41cc and having mounted on these supports a further embodi~
ment of the present invention as illustrated being leveling ".. ;
leg structures mounted,by clamps onto the leg structures 41c '
and 41cc, with a common leveling initiating pedal 14~ The
20 details of the structures of the ~eg leveling device of ', '
Figure 5 are more fully illustrated and described with ,.,`:
reference to the l~igure 6, 6A, 6B, 7, 8 and 9. Except ~or ': '.
the presence of the clamping flanges 44 for clamping onto ~;
the leg structures such as leg structure 41c, the leg embodi- ~,
ment such as illustrated in Figure 8 substantially corresponds
ln st.ructure and mechanism o~ operation to that o~ the embodl~
ment o~ Figure 1~, In the Figure 5 illustration it r~y be
seen the relative locations of the support bar 4~ and the ,`,, .
lever arrn ~lla. AlSo there may be seen the relative locatio~ ,
o~ the actlvating pedal 1~ igures 6, 6A and 6B show in ,:'
- 10 '"'
'
,~ .
in-part view a better relatlonship of these part and thelr
operation. Xowever, their mechanism of operation is better
understood a~ter the description o~ Figures 7, 8 ancl 9.
In Figure 8, there may be seen how the clamping flanges ll4
clamped around tl~e leg structure Illc and in Figure 9 how
the bolt 55 l~ith the wing nut 46 bring together these
flanges 44 gri~pingly to clamp around the leg support struc-
ture 41c. A1SO the relation and location of the pressure
seat l9al and the pressure-applying bar 22c are disclosed.
Upon release Or pressure by the lever bar 22c against
pressure seat l9a, the pressure structure 39c releases its
grip on the leg outward surface 15c such that the leg 15c may
move axially along its longitudinal axis within sleeve 18c ~ -
in the same manner as is illustrated for Figure 1 that the
leg shaft 15 moves within its sleeve 18. The pressure o
the lever bar 22c is regulated by ko and fro movement around
pivot pin 47 by virtue of pressure exerted by lever arm 22c'
through pivot pin 55 connecting lever arm 22ci to the lever
bar 22c. The pivot pin 47 is mounted within the support
23 structure 48.
Accordingly ik n~y be seen that when as illustrated in
Figures 69 7 and 9~ the lever arm 22c~ moves in direction 56
the lever bar 22c becomes wlthdrawn from the pressure seat
l9a~ as is the case in the illustration Figure 6A where the
actu~ting arm 50 is locked by pin 58 against further down-
ward movement in directions 59 o~ the pedal 51, When the
pedal 51 is pressed downwardly in direction 60, the adjust-
ment screws 61 permit downward movement of the pedal 51 to
the extent that the pressure between pressure seat l9a and
pressure b~r 22c are maintained by virtue of a spring biasin
?
10~
struct~ 20c ~hl¢h corr~ponclJ3 in ~un¢tion to that Or
~pring 25 o~ uro 1 and ~prirlg ~5d o~ F~ 3. Al~o
coil ~rlng 62 i~ colmec~d to a ba~e o~ t}~ l~ver arm
porkioII 50a th~r~by s~rvln~ ~o blas up~qardly tho l~Ter pvrtio~
50 a~d r~pectiv~ly th~ k arm~ 54a and 54b and the pivot
- pin 53 aa ~how~ in Figur~ 6B, th~ cha~el t~ough whi~
t;h~8e~ m~mber~ are plvotablo l~nked beiz~g doflned by the
chan~el ~ru~ture 52 OI ~igure~ 6, 6~ a~ad 6B. ThU~3 th~
Fl~e ~A llluat~to~ th~ app~arar~c~ a~ tal~en along ~h~ lln~ ~
6A~6A o~ Pi6~re 6 ~hon ~h~ l 51 i8 in 'ch~ upward po~ltion
in ~hich the le~rsr bar 22~ is pr~ing loGl~blg a~alnst th~ -
lookiz~g ~eat l9at, t~ tat~ o~ b~ing al~o b0in~ r~pr~s~nted `
ln ~ 7, ln wbich tho podal 51 1~ ln th2 oppo~lte posi-
tlon,, ~n th~ oth~r ~3nd, FlF~ 6B illusitrat~ the r~lativ~
p~i~ion o~ th~ l~ver ~o~tion 50 aad tho lev~r~ 54a a~d 54b
wh~ll tho podal 18 in a dow}l~rdl~ pr~ed ~tat~ sa~¢~ that th~ :
.
15c and 15¢ l ar~ movabl~ ln dlrection lo~g~ttld~na}ly Or
~helr.re~æctiY~ l~g ~ ln th~ mann~r ~h~ same a~ illu~- .
~st~d in ~lgur~ and 8 r~apQot~v~ly. A~Pd,~n~ly, by
pr~8~ing do~ntlardly on the ~oot p~dal 51, th~ pr~ re o~ th~
lever bar 22a i~ r~liev~d by ~lthd~l Prs~m th~ pr*87~i~;
~e~t; l9a' ~l~r~by th~ ~t~p ladder l~g~ 15c and 15CI b~¢om~
l-v~l~d autou~Ltlcallg ther~rom, a~tor which the ~edal 51 i~ .:
~llpped bac~rdly 1~'GO all ~p po~i~lon by virtu~ o~ ~anu~l .
~nipulation theroo~. It ~hc>uld b~ r~otod th~t Oh~ r~ec}~anl~m
à~ iliu~t~at~d il~ Figur~ 6, 6A and 6B i~ o~ a toæ~le_~w~tch
~y~o arrange~3t. Althoulæh a ~pri~g r~¢hanl~n; 22
employed in lth~ n~tur~ that a~ ty~lcally lllu~trated ~cr`~
Fig~3 1 and 3 r~p~¢ti~ly, fi~xoep~ be~; m~ ~ th~ ~t~r~
-- 12 - :
-
. , ; . . , , . . , . , . i :
~ a7~1Z
o~ t~a~ lllustrated ~or F16uro 1 and Flgur~ u~h aprlng
meCha~liBm ~llay have substltuted in it~ pla¢~ an equi~l~nt
mechani~ eh a~ the ar~ 27V 27bg 27bt, 27blt~ a~d 22
and/or 22~ bei~g ~u~flclentl~r re~ille~t ~d ~l~xl~le a~
to ach~ev~ th~ sa~ ~rlng biaLsing ~un~on a~ tAat of
~ypically th~ ~pring 25 a~ do~cr~bed in it~ ~n¢tion ~o~
Fl~o 1 ara~ th2 ~prln~s 25b a~ d~s~lbed ln it~ runction ~or
~uro 3. Ac~o~dl~gly, ~ho~ th~ folïs3wlng elair~ r~
~noo` i8 ~do ~o ~u~h a ~prâng ~char~i~m, lt 1~ to be und~r~
ætood that the ~prlng me¢haEIi~m nay b~ erlt and a ~art
of a ~lexibl~ ~atur~ ar~d px~opor~y o~ the lsver a~n itsel~,
~uch a~ ~r tho~e di~eussed i~dla~ely ~bovo.
F~ lO illu~ate~ a lever m~hani~m rQ~ er arm
i~ 32 tho oam0 a~ and a~iogou~ to ~igure~ 5, 6, 6~, 6B, 6C" 8
a~d 9 exc~pt t~t piD 30à al~d ~tr~aeture 3~ ar- equivaleAt to
- pln 53 and æt~ucture 50, ar~d a pætlorl o~ l~v2r 32 ie
pi~ottd o~ a pivvt p:ln 321d uich an actuatl~n arm 35d ~Or
a~ optio~l ~pring 36d,~ th~ r~leaso ~itlon~ belnæ ~ho~n
wlth tho phanto~ po~itio-l 35~d. Tb~ lo~er l~n~h 3ld 1~
en~g~d around pi~ 30d a~d th~ l~v~r 32 ha8 a 810~t~d ~d
29d ~l~o ~oun~ed ~rourld th~ pin 30d, with tho pln 30 beillg
mou~bo~ ta~ u~rdlg an~ dow~rdl~ bl~ ~tru~tur~
339d mo~n~d arou~d th13 up~i~ht pirl 33do T~N ad3wta~le
l~g 15d 1~ ~lampable by th~ plvote~ cla~p po~tion 39td
pivotal3ly mo~ted on th~ ed olamp por~on 39d, ~l~h th~
pl~ot~d p~tion 39td h~ld ¢la~ gl~ a~in~t thc l~g 15d
b~r th~ pin 22d 1OG~d ilito positl~ b~ vlr~tle ~ ~h~
~pandl~ 35~ b~ ~ a dow~rdly lo~k~d ~tat~. Ssr~ 15dd
cur~ into th~ ~app~r park of ~he leg l5d a~ i8 ax~ally
movable in a~3 ap~rture ¢onl;~ lthin the ~3~ru~ 18c~.
- 13 ~
~ ` ~
~~
Figure 10 r~pre~ents an J~n-p~rt Yi~d al~er~at~ ~tep l~d~r
er~bodlment o~ 5. All o~ th~ Flumor~ls o~ thia Figure
co~re~p~d ~o ~imilar rlumeral~ o~ prior Fi~ure~ e3~cept fo~
the letter or rep~ate~ lett~r, o~ pri~e "de~ignation" or
the llke repr~se~ti~g a 9Idi~ren~ abodlment. :Figure 12
lllustrates a vi~w a~ ta~en along llne~ 12-12 o~ 10
bette~.`~ trating the p~vo~ably D~oulked lever 32 on ~h~3
pivot pi~ 32'd ~ith the le~er ~ndlo 35d., liig~
t~ate~ a vi~ a~ along 1~ r ~ o 5~h~ :
. 10 Vi~ ~th~r ela~ th~ r~tl~2~hip b~tw~en th~ ~ario~
~leoent~ h as the lever ~7~, the lev~r link 31a, the pin
.~ 30d, the pi!l 3 ~d, l~v r 32, aad th~ l~ver handl~ 35dO
ure 13A and 13B repr~nt a ~till ad~itlor~al embG;di-
mene o~ th~ pr~ellt inv~tion whiah ~ay b~ a~s~¢lated Eslth
any o~e ~ mQre p~ b~ e~s, the e~ ping n1eeha~lsm f .,.~,
b~ing tho ~am~ a~ a~r one~ oro Or t~e9~ pre~iou~
clo~, but th~30 ~læures d1~lo~ng an ad~an~ag~ous
al~er~a~ely;iDter¢h~ng~ble exte~ded leg, in ~aioh 1~ the
~g~ 13A th~r~ i8 sh~n ~ln an ~xpl~d~d v~ an ~m~odirf~n'~G
ba~cally th~ ~am@ a8 that ~ho~n is~ F~gur~ 13~, ox~pt 1
th~ Figuro 13A e~odi~at the l~er leg p~itioa 15~ ~y b~
of a~ ex~e~ded l~n~th a~ contra~t~d to a ~hcxrk~r 1~
p~tlon 15e~ o~ ~e Fig~o 13E~ ~bodi~nt. Th~ ~urpo~e of
~hls ~mbodi~nt and variatlon of the inv~nt10~ to p~rmit ;
~uba~utlon o~ a lon~sr sn3p~in leg ~n~ ~oot po~tJ.o~ 81
~3ViD~ the ext~nd~d leg p~rtion 15P aa ~ontra~t~d tcs the
~hc~er ~oo~ p~tion 21e havlng the shc~rte~ g p~rt~ 15e
~o~ th~ o~erall l~g coDIblnatlorl 13. The leg p~Ptio~ 152
a~3d 15r are :Ld~nti~ th~ nap-ln upp~r relatio~h~p
~hi¢h 18 o~wn ln detail 113 th~ ur~ 13A ~alth the upper
-- 14 --
pQrtion havlng a ætep lnwardly ~haft ~lth a head 39
de~in~d by a ciroumescribing groove o~ notah 38 lrlto whieh
a sprir~g~ ed ball 37 i~ pre~ad in~ardly to detachRbly
lo~k the ~Bg int~ po~i~ion b~ tbe bia~ g sp~ine m~D~ber 36
~hich i~ held lr~ po~ltion a~ ~ounted with lt~ aperture
~tructur~ around the ball 37 ~re~ing the ball 37 in~ardly
into and part~ally thr~ugh an ap~rlture withln the ~tructure
16e o~ th~ leg pc~tic>rl. Ths relationship for the ~n~bodi~
ment o~ Figure 13B in lo¢hed ~tat~ better ~ho~n ~n the
~lg~e 14 a3 lllu~l~rated ln cro~ ection a~ t~en alo~g
lines 14-14 o~ Figure 13B. ~hi~ Fl$ur~ lllustrates an 1~- ;
p~r~ cros~-~e~tior~l and ~id~ rie~o the ~art num~s,ted above.
It ~h0uld be noted that il~ ~rder ~o ~it any or di~r~t
~ized r~t~ep ladd~rs, the ~r 48 may be extend~able (no~ illus-
trated) al~d ~ edly ~eeured iXl extsnded ~tate, and:~hat ~hen
~ .
ext~ndable iD nat~re, bh~ sprlng d~vice~ 11, 20c, 23b and the
lllæ ar~ auto~t~oall~r ex~ondable; however rods ~uch a~ 22c
may 1nclude additionally insert~d ex~endabl~ units.; Al~o,
- 'che unit~ n~Ly be aval~ble iE~ optio~al alte~ e dimen~ion~.
It i8 withln the ~eopo ~ tho l~ve~tion to make ~u~h
~arlatloDs a:nd modi~¢ations axld ~ub~titutlol~ o~ -qul~aletlt6
a~ are appar~nt t~ a poroo~ o~ ~dlnary skill.
,. , :
; ~ , . ,~ .
