CA2006299A1 - Shoe and elastic sole insert therefor - Google Patents

Abstract

SHOE AND ELASTIC
SOLE INSERT THEREFOR
ABSTRACT
A shoe is provided having an elastic sole insert which compresses and expands when loaded generally axially to the wearer's foot. The shoe includes a sole, an upper member attached to the sole periphery and surrounding the wearer's foot, and an insole. The elastic insert is positioned between the sole interior and the insole. The elastic insert has a continuous outer ring with a cutout region formed therein to define a leaf. The leaf projects out of the insert is compressed.

Description

6%99 P-3 01 - ~
SNO~ ~NID ~I-A8T~C
80LdS INS.~ ~! llSEaE~

F~ O~ O~
The present inv~!ntion rel~tes to the Eield o~
Pootwe~ Rn~ p~rticularly ~ otwea~ having ~n ~l~stlc sole ln~rt.

Sporadiaally over th~ last 100 years, ~here hav~ b~en vari~us a~tempt~ to ~abrl~ate shoe sole~ or in~ h~in~ internal sp~ing~. Early ~uch device~ are ~hown in U.S. Patents 413,693, 507,49V, `9~,120, and 1,Oa8,32~. These early pa~nts, like the mo~e r~ent ~oun~sr-par~, U.S. Patent 4,~22,8~3, utilize heliaally woun~ ~il sprin~ as shoak ~b~orbin~ en~rgy sto~age de~l~e9. A draw back with coll ~pring~ is t~eir height ~lative to th~ir dlameter ~nd thei~ limited r~nge~ In ~rder ~o minimize ~he collaps~d height, coni~lly wound ~o~ 1 ~pr~ ngs hav~ been utili~ed. The most signi~i~an~
pr~lem o~ prior art ~il spring~ i5 their llmited ~nergy ~t~a~e cap~ity. ~dd~tionally, coil ~pring~ ~
con~en~ionQl design ~re di~ ul~ to retaln as their fr~ ~n ~ aau~Q loa~ con~entration~ requiring rigi~
r~iner pl~es ~ rein~or~emen~ ~ructures, as shown in U.S. P~tent 2,6~8,374. U.S. Patent, 4,267,64R (Wei~z) 2S sugg~ts ~everal al~e~natives to ooil sprlngs, sua~ as fla~ di~k springs an~ bell~vill~ washer spring~. In order to ~intain ~ low p~of~le, a large numbex oi ~mall ~pring~ ~re utilized.

QB~E~B~ ~a~URE~ a~a A~AN~aE~ O~I NV~NTIo~
3 0 I~ i~ an ob~ ~o~ of the pr6lsent inv~n~ io~l to pro~rl~ ~in çla~tlc sole in~ert whiol~ on~pact and provides high energy storag~ capa~i~ity.

;~0 [lt~2~39 , - , P -3 01 _~ _ A featu~e QiE the pre6ent inventlon ~s that tll~
in~ert has a 1~rge diameter rel~ti~e to i~ height and pre~.ent~ ~ ~arge .~ I b~rin~ ~ur~ace.
An a~3v~ntage o~ th~ present in~rention l5 ~h~
elastlc in~ert :Ls relatively easy to retaln withln the 6ho~, and ha~: ~ relatlv~ly low wel~ht and siz~3 when compared to prior art ~ev 1 ce~ ha~ring aoJnparable energy .~toraqe a~paoi~y.
~he~e And oth~r ob~ ~ot6, ~eatures and lo ~v~ntage~ o~ ~he present in~ention will become appa~en~
~rom ~h~ f~llowing spe~lflc~t10n~ :

~ QF INVBNTION
Disc:~o~ed i~ a ~ho~3 havin~ a ~ole lnember, an upper meml~er Att~ched to ~he sole and ~urroundlng ~he S ~oot of ~he wearer, and ah insole which c:ooperates wlth the w¢~er ' ~ foot . ~n el~st1~ insert is placed in the ~ho~ between the sole int~erior and ~he insole. The ela~tl~ ~n~er~ de~orm~ along an AXi!i; generally p~rpen~ :
dic:ul~ to ~he ~ole of l:h~ 6hoe. The ela~tic insert h~s ~ t~c\~inuous gen~:~ally planar outer rin~ and ha6 a cu~out region formed wi~hln i~ whlch deflne~ a l~af.
~he l~a~ pro~ eats c~ut o~ t~e plane of 'che ring and ela~ti~ally ~le:e~ when loaded in aompression.

BR~ PTION ~ D~A~IN~93 FI~UP~E 1 is a plan vlew of an elastic ins~rt ~IGURE 2 15 ~ sid~ ~levational ~iew of th~
' islsex~ o~ Figur~ 1; ;
F:tG:UR~ 3 is a partially ~ut-away ~ide ~l~va- : ;
tiQr, oi~ ~ shoe wi~.h a wea~er ' B ~oo't: shown ln outl ine:
FI~URE 4 is a c:ro~ se~tional end view ~iken ~ong lin~ 4~4 o~. Flgur~ 3 ~
PI~UP~E 5 i~ a plan view o~ the outline Or a s~c~e ~howlng khe. in~e~t oriRntation;

09~02/1~184 E17: 59 ~ P~N~FI~X UF-400 ~ 0651135Zl P. 04 ~alo~s~
..' P--301 ~3~
FI~UR~ 6 i6 a p~ane view of ~n al~erna~lve ~la~tia in~ert d~ign;
~ I~URE 7 is a ~id~ elevati~n of t~e in~er~ in Flgur~ 6 in i~ ~ree ~t~t~;
FIGU~E ~ i~ a side elevation oE the in~ert ~h~wn in Fi~U~R 6 in its ~u.lly ~ompressed state;
FIÇURE ~ i~ a plall view o~ a third embodi~ent o~ the el~Gti~ in~rt, the side elevation in ~he free and ~ompres~ed stat~s being substantially equivalent to lO Flgure~ 7 ~nd 8, resp~atively;
FIGURE lO i~ a pl~n vi~w o~ a ~ourth emb~di-~men~ of the ~la~tic in~ertr FI~RE 11 ~ s a ~ide elev~ion of the Figure lO
ela~tla insert;
FIGURE 12 is a load ver6us d~lection gr~ph~
;and F~URE 13 15 a ~chema~ic diag~a~ o~ a aan~ilevered beam.

~CRIPTIO~ @~ RRED EM~OD~N~
20 . Wi~h reference ~o ~ho drawing~, ~ev¢ral pr~ferre~ ~mba~iment~ o~ the invention are di6~ d.
Fig~res 1-5 ~l~ow ~ ~ir~t embodiment o ~lle ela~tic ln~rt 20 ~hown ln an athlRtlc shoe 2~. In th~ ~r~-~rred embodimen~, the ela~tic in~e~t 20 congist~ o~
25 upper an~ lower elements 24 and 26 6hown in Flgur~ 4 ~ n~d in ~taGked alignment alon~ a common axi~
upper an~ lowe~ elements 24 and 26 are substan~l~lly iden~ical to ~0 another and a~e ~entrally attac~ed to one another u~ing a rlve~ ~B or the like whi~h a~t~ as ~0 a ~a~tener m&an~ ~or attaah~ng thQ upper and l~w~r e}emen~ t:oye~her. Each of ~he upper and lower elem~nts ~: ar~ ~r~cl of an ela~tically def~rmabl~ mat3~ial ~u~ as - a ~prlng st~ h~et or ~e 11~e. ~ach ~lement h~
continuou~ and ~en~rally pl~n~r out~r ring 30 havi~g a ' .~ "'.
,,.~, ,.

09/02/1984 E18: 00 )~ P~ lFflX UF-40E1 )1~ 06510521 P. 05 .- ,,- . , -Pw~Ol _4_ cutout reglon 32 ~ormed ~lerein which de~ine~ a~ 34.
The ~eaf extend~ inwa~dly from the vuter ring 30 an~ ls prQ~erably o~ a spiral ~hap~ a~ ~hown in the Fig~re 1 plan vlew. ~he lea~ ter~inate9 in ~n enlar~ed bos~ 36 5ha~ln~ a cen~al hoL~ 3~ for xeceivin~ rive.t 28.
A~ ~ho~n in the FlcJure Z ~id~ elevation, o;~t~r rlhg 30 is generally planar. ~eaf 34 projects out o~
the plan~ of ~he rin~ in the ~ree state. The ~eet matar~al formlng the element 26 ha~ a thl~kness T, and the ~l~ment has a ~re~ height H a~ 3hown. The max:imum de~lec~ion i~ ~he di~fe~en~e between the ~ree hei~pt H
: nnd ~hi~knes~ T. The ela~ti~ elemen~ may be ~omp~s~d ~epeatQdly from its free height t~ the totally ~lat position without fa~iguR.
Lea~ 36 ~s as a can~ilever beam f~xed at one end and loaded at the oth~r. The leaf is a~ixe~ to ~he ou~cr rlng and extend~ inwardly therefx~. The lea~ has an uni~orm thickness ~ and a varyin~ wldth. ~h~ leaP
~dth ~g greate~t a~a~ent the outer rlng 30, and tapers t~o ~ minimum width ~djao~llt the central boss 3~. ~y u~ilizing ~ ~piral deslgn, a greater be~m len~th can be ~chi~ved. Th~ ~piral design aau~es the lea~ td be l~a~le~ in torsion, as well a~ #ltnply in sheer and bQnding~ A!3 would b~ ~h~ c:ase in a strai~ht ~e2tm ~5 cantileveredly a~xed ~o a rigid body at onQ ~n~.
Whe~e ~he e~a~tiQ in~ert i~ mad~ up of an upper and lower elemen~ a!4 shown ~n Figure 4, the free hei~ht, aompres~ed ~hicknes~, an~ u~ef~l range will ~e t~lce th;lt of ~he ~ ngle ~lemen~ .
Shoe 22 iR mad~ ~p oP a ~ole member 40, an upper memb~r 42 and an insol~ 44 . sc: 1~3 40 hasi an exkerior sur~ae 4~ and An interior ~urface 48. T~e upp~r memb~r 4~ i~ aPfixed to th~ periph~ry o~ th~ ~ole and gbnerally Burrounds the ~oot ~ the weare~ n 3~ oonventlonsl manner. ~n~;ole 44 ;:on~orms to ~he $ole s~
~".
09i02/lg84 08: 00 ~ PRI`IRF~X UF-400 ~ 0651E~521 P. 06 ~Çi299 P 3Ul -5-int:e~lor sur~;~ce and cooper~teE; with the foo-t o~ the shoe wearer in a typic~1 ~ashion. Bet~een the ~ole in~ or and the in~ole i~ a c~vi~y 50 in which the elaJstla insert ~0 is inE;tallQd. As the fo~t o~ the ~hoe we~e~ exçrts a loa~ ~long the in ert axis, leaf 3~
el~!;tlo~lly de~lect towar~ th~3 plane of the outer ~ing.
A~ ~he shce wea~er runs or ~ump, the load exerted ~Ipon the insl~rt will aau6e the in~ert to co~npress an~ exp~nd, E;toriny and releasin~ energy. In the pre~e~red embcjdi-men~ of the ~ hven~lon shown ln Figure 4, a thin ~ n~ole reinforcement 52 is provlde~l tc~ pre~tent the so~t foam insole 44 frc~m dePor~nin~ into the element autou~ r~ I on 32 .
~he elastic insert i~ par'cic:ularly b~ne~ ial in an athletic sho~ u~e~ in ~l~mp~ng sports, ~uc:h a~
l~a~ketball and volley1~all. The in~erts are also llel~u~
ln runn~ng shoe~. D~ring a running or ~umping ~tep, th~
load i~3 ~r~n~mitted Erom the wqarer's ~oo~ to t21e ~rc~untl ;: -th~ouyh ~he sh~e ~ole. In a typical ~ho~ du~in~ a .
~0 ~umping mfln~uv~ th~ sol~ is compressed during inl~
tlon o~ th~ ~ump and expands ~o the original h~g~ ~nce ~h~ ~oe i3 ~ep~r~ted Prom th~ groun~. A typi~al ~hoe ~
Gola is re~ak~vely inela~tic and i~ very ine~ficien~ at -:~.
r~leagin~ ene~y during the ~umping man~uve~ d~ to ~igh ;~
hy~tera~ Inse~ts o~ a pr~sent size ~re very ela~tic wi~h relatively little hysteresis thereby releasing the :
maximum am~n~ of energy durlng a ~umping ~aneuver. ; :~
Preferably, each ~ho~ i8 p~o~ided with two . ~-:
ela~tlc in~er~, a~ shown in Fi~ures 3 and 5. one ~
~o in~ert 2~ lo~ate~ in the shoe ~ole adja~ent ~he we~r~'s ~ ~:
heel and the o~her inse~t 20' oriented ~elow the ball of -~;~
~.
the weArer~S foot.
Init~aL tsstin~ has ~ndlcat~d that th~ ela~tic :.-ele~ent ha~ing a aompre~ion ran~e ~f .27 in~hes a~d a ~pri~g rat~ of 1~ pounds per in~h performs sati~a~

~ ,~
. .

09i~l2~1gl~4 08:01 ~ P~l`IRFRX UF-'100 :J~ ok 065105~1 P.E17 29~3 toril5r in a ~hoe worll by a 1.60 poun~ persorl. Ide~,illy, ~n insert will be s~lec~ec~ which has the highest ~p,ring ra~e pos~ible ~n~ wl~ h will s~ill enable the insen~ to ~e fully c:ompre~secl at ~he comm~ ement of the mu;~:~le c:ontr~ ion or po~i~ive mo~r~men~ portion o~ the ~u~ping man~u~er. Too stl~ o~ an ln~;er~ will not enable the :I n~;er~ to k~ fully c:ompre~E;ed during the n~uscle contras~tion or negative mov~nenl~ portion of the jump.
he ~p~ hg i5 not fully oompressed at the 1~ ~ollunencement o~ the muscle con~rac~ion, ~ un~ing perfc~r~anc:e aan ac:tually be hindered a~ a re~ult of, the in~ert~ limlting the ~orce whi~h can be exerted dup~ing a portion of the mu~ contrac~tion. Too ~o~t o~ ~n in~ert will not store the maximum amount of ~ne~gy, lS there~ore limiting the bene~ ial ef~ t of the in~3ert and po~sibly resulting in exces~ of de~ormation du~inq norm~l wal~ing. While ideally the in~e~ spring rate wou~d ~ speçi~i~ally ~ele~ted ~or each wea~er ~onsi~er-ing th~ we~rer'~ welght and Athletic ability, ~ommer~
~o sho~s hAving permanently installad inserts can b~ ~ade with re~ula~ o~ ~iff ~nsert~. spring rate of the i~ert3 woul~ al~ vary as ~ function o~ shoe slze.
~or jumping ~p~t~ it is bslleved that ~all an~ ~eel el~tic ~lemen~ ~hould haYe a sub~t~ti~lly equ~l ge~ ry and spring ~ate. It should be re~ogn~z~d that the heel an~ ball prl~g rates can be varle~ as de~ired ~epending upon the expea~ed us~ of the shoe. It ~ho~ld al~o ~e appreciated tha~ only a single lnsert;may ! be u~ed in certain cir~u~tance6. For example, a lpng-di~an~ runnlng shoe may utilize ~ heel in~ert ~nly while ~he slp~inter's shoe may utilize a ball in~ert-o~lY-~ s~aor~d embodim~nt 60 o:C th~ ela~tt~ in~rt hown in P'`igure9 ~-a. The lnsert is fo~ed ~f a rect~ngular sheet 62 having a cutout 64 formed thetein t39/E12/1~84 08:132 ~ P~ fF~X UF-400 rl~ 06510521 P. 08 ~ ~06~99 P-301 ~7~
which ~hould de~ ne a con~inuoll~ out:er rin~ ~6 a~d a pl~lrality of leave~ ~8, ~8 ', 63 ", 68 " ' pro~ ect~ng in~ard-ly ~rom the outer ring ~ rhe insert is p~efe ~bly mAde llp o:~ upper an~ lower ~lements 70, 72 ~ ;ho n in Figure 7. The outer r~ns~ 66 of each elem~ant is g~n ral-ly plan~r and par~llel ~ h~ ~hoe sole. rhe eleme t Yg elasti.~lly de lectable alonq an ~xis generally pe~pen-~i~ular ~o ~h~ 6hoe ~iole. ~rhe leave~ of e~oh el6~ment prvj~ct out of the pl~ne o~ the xing i~l the ~ree ~tate a~ ~own in Figure 7 and c:oope~te with the corres] ~ond-ing leaP ln tha o~her elemen~- The ends of the l hves ar~ locally parallel to 'che opposing lea~, a~ ~how l.
Pre~erably, as in the f irst embodiment, the leaves o~ the upper an~ lower ~lement are fas ened ,~5 togOEther using a suita~le fas~ener 6uch as ~ riv ~ or the like . Al~o ~imilar to th~3 ~irst em~odiment ,l th~a elas~ic element h~ a fully compressed hei~ht equ~l to two ~i~e8 the shee~ thicknes~ T ~ ~n~d the leave~ are ~en~ally t~pered having a width greates~ adjac~nl the out~r rlng. ' A ~hird em~odiment of the elastio insert p~ ia sh~wn i~ u~ 9. ~he di~ren~e ~etween in~ert 7~ and insert ~0 i~ web 78 which ~xtends aoro~3 the 1~sert connacttng ~n opp~ite o~ ~hQ ~l~m~n~ outer r~ngl It 2~ should be ~ppreciated that a w~de varlety of ~lea con~igurations can be ~onstructe~ by cuttlng one or mor~
cutou~s o~ various shap~s to suit ~he desired app~laa-tion. ! ~-:
: ~ A ~ourth ~mhodimen~ o~ the el~sti~ inse~t 80 1~ shown Figur~ 10 arld 1~. Pre~erably, lnsert ~0 ls made up of upper and lo~ar elements in a similar fa~h~.on as the earlier em~odi~en~ described. In~ert ~o is ~imilar in appearan~ tQ i~rt ~0 shown in ~igu~ .
~nd 2. A ~ir~t and a ~eoond outout r~yion 8~ ~nd 34 i~
~orm~d in the e~ast~ inser~ ~o define a gene ~ally 0~fE~ 3~4 08:~2 ~ PRNRFRX UF-4~ 0651~521 P.0~
2~9 .
P~30~ ~8-- .
spiral ~h~ped lea~ 8~; af~ixed ~t bokh ellds to aontinpous outer ring 88. The le~ h~s a central boss 90 a~d a hole 9Z prc~ d ther~in ~or atta~hment o~ q ~l~re'ç or ~he ~ike. Th~ l~a~ i~ wida~t a~ ~h~ ou'cer ~ing ~B, and b~com~ narrowest at the ~tta~hP~en~ ~o the bc)ss 90.
El~stic: element: l~O ~Xhil;~it~ lfl~tly different load ~er~;us de~lel~tion ch~r~¢~eristlcs than pre~i~ly de~oribed elastic elemen~s utilizing l,~aPs of celn~lle~er de~ign. LeafE; of a c:an~:i le~ter de~i~n have a ~airly linear load ver~u~ ~efle¢tion curve aæ showh on line 94 in Flgure 12. In order to inorea~e the en~rgy storage capacity of the ela~tl¢ insert gi~ren max~m~n load, a non-linear load ~re~u~ deflec:tlon curv~ is pre~rred and which has an initial~ y steep slope a1~d a very low ~lope high defle~tion, ~l~stin elem~n~ ~0 combines ~he loa~ ve~su~ d~fleo~ion ch~racteristic~ of the aantil~ered ~prin~ shown in curve 94 Wi~ ha~ ~
~o~e ~prlng or bell~ville w~er represented by ~ e to aah~eve t~e load v~r~u~ de~lectioll curve repr~-~ented by line 9~. ; -P`~re 13 ~h~w~ a ~ohematio repre~entatioh of ~ cAnt11~v~re~ beam af~ix~ at one end and load at:t~e o~her. B~am 100 ha3 a length 1. When ~orce ~ 1~
exerted on th~ ~ree end of th~ beam, the ~rae end de~le~ts a ~is~ance ~. ~ef~Qc~ion in the cla~cal ~antilevered beam shown in Figure 13, i5 expre6se~ by t~e ~ollow~nq equation:
d - ~13~3EI .
Where ~ i~ equal to the modulu~ ela~ti~ity and I i~ ~he beam moment of lnertia. Force F i~ exerte~ on the en~ of the beam aau~e~ an equal and oppo~ite rea~tion force ~R at the wall a~a~hment. For~e F ~l~o cau~c a bending moment M~ to be ~xerted at t~a ~all att~chment, where M~ equal~ Fl. While the sheer lo~ on ~he ~eam i~ uniform th~oughout lt~ len~.3th, ~he mo~ent El9/E12~1~84 08: 0~ ~lok~ Pf~l`lflFf~X UF-41~10 ~ 06510521 P. 10 6~99 P-301 -g-v~rie~ directly propor~ional to th~ l~ng~h. ~t'the wall, ~n~in~ momen~ i5 maximum, at th~ ee end ~f!t~e b~nding mom~nt i~ zar~ with a line~r progres~n thereb~tw~en. Th~ bending loal~ exerted nn the b~am ~111 ther~or~ b~ gr~atest ad~c~r~t t~e af~ixed ~t~h ~ n~, and the mlnimum at the free end.
In order ~o p~even~ ~tres~ c~ncen-tration, and ~o minimize th~ weight of the in~ert, in th~ var~us pre~err~d embo~iment3~ the leAve~ ar~ gener~lly tape~ed, bei~g ~idest adj~oen~ the ~uter ring, and narro~e~t ~diaaent ~he loading point. This tapered leaP d~ign re~ults in ~ ~ub~an~ially unl~orm s~res~ d~s~rib~ on.
Beam ~ in in~ert 60 sh~wn in Figure 6 act~ e a ola~s~c~l aantilever beam as shown in Figure 13, ~i~h ~he exoeption that its width and moment of ine~t~a varie~ a~ a Function of length. The .beam iB loade~ ~n both the bending and ~heer m~de~. ~he ~plral ~e~f de~ign in~orporated in lnsert 2~ is also loade~ in torsion~ The relative magnltude o~ the bendlng in,the ~orsional load varie~ throu~hout the beam len~h ~g a ~unation of ~eometry. In the embodimen~ o~ the in~ert show~ ~n Fi~u~ 1, over ~wo-thir~s o~ the energ~ ls ~or~d in the ~pring a~ a re~ult oP tor3lbna~
de~orm~t~on~ In in~rt 80, in addition to shQer,ben~ng :~
and to~ion~ ~he beam is al~o loade~ in akia c~mpre~sion.
A~ a result of ~orm~ng the inser~ ~rom a ~e~t -~
Of material h~ving an uniform ~hickne~s, tlle lea~
~ ha~e a generally r~ctangular cro6s-~eGtional area ha~ing :~
a wi~th subs~antially ~reater ~han its th~c~nes~, The re~tan~le shape enable~ the polar moment inertia o~lthe le~f oro~ section to bs maximized to bet~r re~l~t ~ ~.
torsi~n ln ~h~ ~pir~l lnser~ de~igns shown ln Figu ~ 5 1 ~n~ 10.
35 The ela~ ins~rt~ in the pre~e~red 09/02/1~4 08:03 ~ Pf~ F~X UF-400 *>lt~)k 06510521 P.11 , P~301 e~bodlment ~an he ~abric~ted of high quality sp~ing ~eel~ ~uc~h a~ SAE g254, SAE 10'~4 c~r e~ui~lent, bu~ it ~hould ~e ~pp~eci~ted tha~ o~e~ ~aterials ~ul~ be u6ed. Common ~pr~n~ m~teri~ nd their proper~ie~ are li~ted in Mark'~ S~and~rd Han~book ~o~ Mechantca Enqineering, 8~h Editlon, pageR ~-7~, which i~
lncorpora~ed b~ reference herein, Other m~terial, ~uch a~ titQnium sheet or molde~ fiber rein~orced composite~, could al~o ~e used in appli~ation where weight, is a~i~ical.
In or~r to manufacture an slastic ins~r~, flat plAt~ sto~k, such as spring ~t~l 3to~ havlng',the zlppropria~e thi~ksleYs is ~;elected. While the ~-t~e~
in ~he ~nne~led ~tat~, it i~ cut to the ~e3ired l~n view u~ing a milling or s~ampin~ operation. Pre~era ~y, the in~ert i5 de-bu~red to remove ~harp corner~. The leaf is then pla~ti~ally deformed ou~ of ~he plan~ o~
the outer ring to aohieve the de3ired free height, ,The el~ti~ ins~r~ element i3 then heat. treated u~i~g a conven~ional quenching techniqu~ to hArden the spr~ng.
In the pre~rred embodim~nt wllere the ela~tic ins~r~ is m~de up o~ a p~1~ o elements, the two elements~ar~
axl~lly ~lign~d with th~lr le~v~ en~ag~ng one ~nothe~
and fas~ened toget~er using a rive~ or the lik~
~5 It. i~ also unders~ood, o~ ~ourse, that w~ile the form o~ the inven~ion herein shown and ~e~cr~d oon~titut~ a pxeferred embodiment. of ~he invention~ it i~ ~ot ~ntend~d ~o illustrate all possible f~rms ~h~r~bf~ It will also ~e understood tha~ ~he words ~sed are ~ords of des~ription rather than limitation, and tha~ ~arlo~ ~hanges may ~e made without depar~ing ~rom the s~irit and s~op~ o~ tho inv~ntion ~i~closed.
.

~ .. : ,.. .. . . . .. .. . .
~.,, ' . . ; ~ ; . . ! , ~ "

Claims (22)

1. A shoe to be worn on the foot of a person, comprising:
a generally planar sole member having an exterior and interior surface, and a peripheral edge;
an upper member affixed to the sole periphery to generally surround the foot of the wearer;
an insole conforming with the sole interior surface for cooperation with the foot; and an elastic insert oriented between the sole interior and the insole elastically deforming along an axis generally perpendicular to the sole, said insert provided with a continuous generally planar outer ring having a cutout region formed therein defining a leaf projecting out of the plane of the ring in a free state, said leaf elastically deflecting toward said plane upon the exertion of a load along the axis.

2. The shoe of claim 1 wherein said elastic insert further comprises an upper and lower element oriented in stacked alignment along a common axis, each element provided with a continuous generally planar outer ring having a cutout region formed therein defining a leaf projecting out of the plane of the respective ring in the free state, said leaves projecting toward and cooperating with one another.

3. The shoe of claim 2 wherein the elastic insert upper and lower elements are substantially identical in configuration.

4. The shoe of claim 3 wherein the insert further comprises fastener means for attaching the leaves of the upper and lower elements together.

5. The shoe of claim 2 wherein the outer ring of the upper and lower elements are substantially circular.

6. The invention of claim 2 wherein said insert outer ring is substantially circular.

7. The invention of claim 6 wherein said insert leaf is substantially spiral in shape.

8. The invention of claim 2 wherein said insert has a fully compressed height which is substantially equal to two times the ring axial thickness, and can be compressed between the free height and the fully compressed height repeated without fatiguing.

9. The shoe of claim 1 comprising two elastic inserts, a ball insert generally underlying the ball, and a heel insert generally underlying the heal of the foot of the wearer.

10. The shoe of claim 9 wherein each elastic insert further comprises an upper and lower element oriented in stacked alignment along a common axis, each element provided with a continuous generally planar outer ring having a cutout region formed therein defining a leaf projecting out of the plane of the respective ring in the free state, said leaves projecting toward and cooperating with one another.

11. The shoe of claim 10 wherein the outer ring of the upper and lower elements are substantially circular.

12. The invention of claim 10 wherein said insert has a fully compressed height which is substantially equal to two times the ring axial thickness, and can be compressed between the free height and the fully compressed height repeated without fatiguing.

13. An elastic insert for installation in a shoe sole which deforms along an axis generally perpendicular to the plane of the sole in response to the load exerted by the foot of a wearer, said insert comprising a continuous generally planar outer ring with a central cutout region formed therein defining an inwardly projecting leaf extending out of the plane of the ring in the free state, said leaf elastically deflecting toward the plane of the ring upon the exertion of a load along the member axis.

14. The elastic insert of claim 13 wherein said elastic insert further comprises an upper and lower element oriented in stacked alignment along a common axis, each element provided with a continuous generally planar outer ring having a cutout region formed therein defining a leaf projecting out of the plane of the respective ring in the free state, said leaves projecting toward and cooperating with one another.

15. The elastic insert of claim 14 wherein the elastic insert upper and lower elements are substantially identical in configuration.

16. The elastic insert of claim 15 wherein the insert further comprises fastener means for attaching the leaves of the upper and lower elements together.

17. The elastic insert of claim 14 wherein the outer ring of the upper and lower elements are substantially circular.

18. The elastic insert of claim 17 wherein said insert leaf is substantially spiral in shape.

19. A shoe to be worn on a person's foot comprising;
a generally planar sole member having an exterior and interior surface and a peripheral edge;
an upper member affixed to the sole periphery generally surrounding the foot of the wearer;
an insole conforming the sole interior surface and cooperating with said foot; and an elastic heel insert and an elastic ball insert oriented between the sole interior and the insole, generally beneath the heel and the ball of the foot, said elastic inserts each independently deforming along an axis generally perpendicular to the sole, said inserts provided with a continuous generally planar outer ring having a cutout region formed therein defining a leaf projecting out of the plane of the ring in a free state, said leaf elastically deflecting toward the plane upon the exertion of a load along the insert axis.

20. The shoe of claim 19 wherein said insert is formed of a spring steel sheet.

21. The shoe of claim 19 wherein said leaf of said insert has a rectangular cross-sectional area having a width greater than its thickness.

22. The shoe of claim 19 wherein said leaf of said insert is tapered, being widest adjacent said outer ring and narrowest at its loading point.