US2629189A - Multiple acting heel for shoes - Google Patents

Description

Feb. 24, 1953 H, C, STElN 2,629,189

MULTIPLE ACTING HEEL FOR SHOES Filed July 5 1951 Patented Feb. 24, 1953 2,629,183 MULTIZPLACTI'NG'FHIL 'Foirs'iIoEs `Harry Charles Stein, Yonkers; N. Y.,.assignor of one-fifth to: Leonard J. SteimuHouston, Tex., onefifth to Stanley M. Stein, NeWQrleans, I .a., one-fifth to Melvin Stein, Jackson Heights, and

one-fifth to Frank R. Stein", Yonkers, N`. Y.

Applicatioiiily, 1951, Serial No. 235,268 @itin-ms. (o1. esl-'8.5)

This invention relates to footwear and more particularly to ai she` providedfwith multiple heel elements for supporting. different parts of the, foot during forward motion.

When all person walks. vunshod,` and the e'x.- tended foot makes initial Contact with the ground, the weight `of the. body is transmitted tof the surfaces `of 'the heellbone, or thelo'scalc'is,` which acts as a pivot as ittrollsover the` ground. However, `when thelfoot `isencased VinI al conventional shoe'therfoot `is anchoredan'd lthe'os calcis cannot-'rotate withz respect to the shoe. As' ar result when thesho'erst'rikes the 'ground during Wallri'rig-the` foot pivots'about theA lower posterior margin of the shoefheel: This posterior margin ofl'the "conventional shoe fheelfe'xt'ends vhack a distance fromthe osc'alcisl which forms a substa'ntial rigidL straight Jleverorf's'plint. The rigid lever' prevents the.4 os calcis" from` performing its" natural movement when? the foot contacts the ground, causing an irregular-anduncentra lized Wear ftheshoe h'eelA and`l'lio`reimportant Accordingly, it. is alpri'nipai object or fmiy'r is: version: rolf avoid-1 these disadvantages luptingiftiie rigid leverbetween l the` os fcalcifs vationview oithe-heelportionof a conventional rightI shoe` in a standing position showing` the bone structure ofthe foot positioned therein viewed from its lateral aspect;

`Fig. 2 is a similar view of the'conventional shoe when the leg isext'ended forward andthe posterior margin of the shoe heel initially ,enf

gages the ground, and the heel of the foot; is resting against the counter of the'shoe after slid ing;

. Fig. 3l is an enlarged partial diagrammatical` elevation View of the heel bone of the right foot showing the os calcis in the initial position and the iinal position shown in dotted lines' during the rolling action when walking AunshodA position, corresponding to the position shown in` Fig. 2;

` Fig; 6 is a top'plan` view of the multiple heel;

illustrated 'in' Fig. 4;

Fig. 7 is an enlarged cross-sectional elevation View of the rear of a mo'dicationprovided with acushion insert in the outer heel element;

Fig. 8 is an enlarged top plan View of tliei'earl of' a right" shoe showing a further modiii'cation wherein the inner heel elementV is forwardly.

hinged;`

Fig. 9 is an enlarged partial top plan View of the 'rear of a right shoe showingA another r'nodi-l fic'ation `in which a` plurality of inner heel ele# ments `are provided;

Figa 10 is an enlarged topplan View ofthe rear of a shoe showing still another modiiic'iai'iiriY in which the posterior edge? oi-` the inner heel element is" formed on an oblique line n'orrr`1'a`gl-` to aplanetpassing approximately througlithe great-- tion View ofthe rear oil" alrightz shoe' sh'owi stru another modification prvidedlwitn andar-V mfg inner heel element: and

Fig. 12 shows a top view f niemuitpishne heel shown in Fig. 11.

In fthe drawing reference numeral Hl designates a conventionalshoe having a heel I2, soleA Mand-r1 an upper i6. Positionedwithin thelshe asshown-1A inwFig. `l are illustrated some of the bones of tlie-` fo'ot, namely, the os" calci's or' heel Vbone I8;` cb'oid 211i-metatarsals` ZZand phalanges 24;4

n order to understand applicants invention it is necessary to consider the movement of the bones of the foot when walking unshod. Fig. 3 illustrates the position of the os calcis bone in the initial and final position upon contact of the foot with the ground 2B after the motion has been initiated. inV which A indicates the position of the os calcis when the foot is normally extended forward andthe pressure on the os calcis is created upon contact with the ground, at substantially two points, namely, on the slightly convex postero-inferior surface 28 and the medial tubercle 3l). This is the position of the os calcis as the foot initially contacts the ground, and it is the most stable position in that the foot is well balanced with the weight of the body distributed on at least two points on the os calcis. YIf the length of stride is increased the foot will be supported solely on the rounded postero-inferior surface 23. The stability of the support accordingly decreases when the maximum length of stride is approached. If the length of stride is a minimum, the point of initial contact and shock will be only on the medial tubercle 36.

YReconsidering the initial position A as the body moves forward, the weight of the body is shifted to the medial tubercle 3G, which thereafter acts as a fulcrum, and the foot rolls on the medial tubercle until the foot is flat on the ground, as indicated by the os calcis in position B. In the average adult foot the medial tubercle is in the form of a ridge measuring about 3A inch in width and about 1%; inch in length. At position B the foot is in the same position as in standing, and the weight of the body is transmitted through the os calcis and directed solely on the medial tubercle. Thus, the medial tubercle in acting as a pivot for the foot during the stride forward causes a forward motion of the foot. In the adult foot the distance of this forward motion, or roll on the os calcis is about 1/2 inch to 3A inch.

"With the above bio-mechanics of the unshod foot in mind, consider the same foot movement with the foot shod in the conventional shoe as in Fig. 1, where the foot is shown in a standing position and the metatarsals 22 and phalanges 24 are bearing against the sole I4 of the shoe. The

around the pivot point 32, which the bones of the foot tend to balance by pressure against the upper of the shoe. This counter-balancing action by the foot bones against the shoe upper causes a rubbing action against the skin and a strain in the bones and muscles of the foot and the fore leg, resulting in fatigue and heat due Vto friction. The longer the lever the higher the foot must be lifted which also increases the force exerted by weight of the body is transmitted to the shoe heel g Vand the phalanges 24, which must necessarily contact the upper I6 of the shoe when the foot is initially lifted off the ground, resist the counterpressure created by the contact of the shoe with the ground. Because the foot is tightly embraced by the shoe the foot remains supported on the medial tubercle although the foot may slide rearwardly depending on the longitudinal clearance present between shoe and foot. The point of pivot for the foot is now at the lower hind margin of the shoe heel and remains there until the foot is rotated to the original position as in Fig. l. The distance from the point of pivot 32 on the ground and the medial tubercle forms a substantially rigid lever, which since the foot is tightly embraced in the shoe, in effect forms a rigid extension of the foot. As the center of gravity of the body must pass through the point of contact of the foot, which in the conventional shoe the medial tubercle, a moment is created the bones of the foot and muscles of the leg.

The moment created by the lever in the conventional shoe heel also causes a greater force to be applied to the medial Vtubercle as the shoe pivots on the ground, increasing the likelihood of local pressure and friction on the medial tubercle ultimately causing organic changes in the tissue. Y

In addition, by creatingra point of pivot 32 for the foot outside of the foot and laterally spaced from the medial tubercle, there is a shift of the centerV of gravity from a line which would normally extend through the leg bones, through a new line posterior thereof. This action results in an increased bending force on'the leg bones and a corresponding strain on the leg bones and muscles. Y

As the os calcis is unable to roll in the conventional shoe heel, as it does on the ground when walking unshod, the entire weight of the body and shock due to walking is always concentrated on the medial tubercle surface which is relatively small in area. This action causes thinning of the protective fat pad of the heel, localized ligamentitisperiostitis, bursae, and spur formations, and other painful disturbances.

rhe sliding action of the foot in the conventional shoe on the medial tubercle until the foot reaches the counter 33, and forward when the foot is brought down also causes a disadvantagecus rubbing action andheats the foot through the friction created.

I have discovered that I can eliminate the above disadvantages of the vconventional shoe by constructing the multiple heel 34, one form of which is shown in Figs.;4, 5 and 6. The multiple heel 34 comprises an outer or peripheral minating short of the forward edge 42 of theV heel providing an integrally attached hinged portion 44 about which the inner heel element 38 may flex, and a connecting portion 46 on each side to the outer heel element 36 for supporting the flexing action. Apertures 4l may be provided at the end of the slit to prevent tearing.V

To obtain a Water-tight construction and prevent the seepage of moisture and entry of foreign matter into the shoe through the slit. I may provide a flexible material that is positioned in the slit to act as a seal as will be later described with respect to Fig. 11.

In operation and following through the same movement as with the conventional shoe described with respect to Fig. 2, when the fore leg of the user having a shoe with the multiple acera-rsa:

ment has been initiated, the outer heel elementl 36 strike'sthe ground at its rear margin IB-and performs its function as an anchorage means preventing the foot" from slipping, see Fig.` 5.

Immediately thereafter the outer heel element 36 flexes under the weight of the body until the inner heel element 38 contacts theground at its rear margin` 50. During this action there may also be a slight flexing of the inner heel velement 38; The weight of the body is-transitted through the leg bone, to the os calcis, and the medial tubercle which bears on the inner heel element 38'. A pivotalaction of the foot with re'- spect to the ground occurs at the lower rear marginA 58 of the inner heel element 38.

The foregoingv pivot point 50' of the shoeat the inner `heel element is substantially vvertically aligned with the leg bone through the medial tubercle. inate'd, `which is present in the conventional shoe, relievingthe muscles and bones of the leg and foot from strain and fatigue. Not only are the muscles andbones of` the foot and leg benefited bythe elimination ofthe longlever` extension of the foot during movement, but benefit also occurs when starting of forward motion from a'` standing position, as the foot must roll back slightly to enable the ieg to be lifted off` the ground. Additionally, the contact of the outer 54 of the outer heel element engaging the rounded postero-inferior surface `28. A two point supportl for the os calcis is thus provided, similar to that which occurs in the unshod foot, with the major weight of the body being absorbed by the medial tubercle and the remainder absorbed by the postero-inferior surface 281which1 acts to balance the forceon the medialltubercle.

The upper edge 54 of the outer heel element, in addition to serving as a support to balance the weightof` the body, functions to prevent the sliding actionof'the'm'edial tubercle on the shoe, thus` avoiding the rubbing action and the in'- juries tothe bone and tissues resultingtherefrom'.

The slit 40 may extend transversely through the entire shoe at the heel and preferably along an oblique line as shown in Figs. 4, 5 and 6. The oblique line provides a greater supporting surface at the upper edge 54 of the outer heel for the postero-inferior surface 28 of the os calcis. The slit should be sufficiently wide to permit unrestricted movement of the inner heel element.

The resiliency of the inner heel element provides a cushioning effect on the foot minimizing the shock from the engagement of the outer shoe heel with the ground. The inner heel element absorbs the main shock caused by contact with the ground and takes more of the wear reducing the so called worn down at the heel appearance that would normally occur at the outer heel element 36 or in the conventional shoe heel I2.

In Fig. 7 I have placed an insert 55, made of any `suitable resilient material, in the outer heel element 56 along the upper forward edge to provide a cushion for the os calcis when engaged by the postero-inferior surface 28 and give greater support and comfort to the os calcis.

Consequently the long lever is` elim-- 6 rigs. la; sand-101rznavefeprovidca' 'aimerait modifications of my novel multipl'e'heelin'whichi the configuration i of the linner heell elementmay be varied. In Fig. 8` the inner heel elementi 58l within the heelitself. 'Ilheslit i2m`ayE vary ini.

length on each yside to provide more or less resiliency `on a particular sidey of the =1 shoe 'if this result is foundl desirabl'ei A In Fig. -9` Iprovide an outerheelelement and a plurality ofA inner `heelyelem'ents 68 and* '50; which may -be concentrically` positioned and separated by respective slits '12-` and 'HLl -Byfexe tending the slits IN2` andv 14 for differentlengths; each heel element vmay have -a differentresiliency' and Vproduce'a cushioning effect for the oscalci'sU in a manner shown in Fig. 5 or Fig. 7i'. 'I-h'ein'ne'rl heel elements B8 and wmayleach have the-sameV configuration or may vary in design.`

A study of the bonesfof the foot will showthatV the medial tubercle` is a lridge-like formation, as previously described, and eXtendsalong la Iline oblique to the longitudinal centerline of' the-footbuti substantially normal to a plane passing through the great toe. Inhthis manner the-un sliod foot pivots on the medial tubercle-in the* plane containing the large toe andthe 'weight' of the body when shifted is` distributedalong the Vaxis `of function between the `medialtubercle and the ball of thejgreat toe. Ihave simulated this 'natural' action by my construction in Fig. l0 in which the inner heelelement 'It-'is cut atia` bias with therear edge'l8V` formed alongan oblique `line substantially parallel to 'the medialv tubercle and the slit 88 formed to provide ahinge S2 along a line parallel to the rear edge '13. When the foot pivots on the inner heel element 'I6 the force due to the weight ofthe body will be distributed to the great toe 'along a linencrmalto the hinge and the rear edge 13. Whereas inFigs.y 6 `and Qtheinner and" outer heel` elements maybe integrally'attached within` the. heel, and in Fig; 8 the integral attaching' means" may be thesole 64'; Ilmayprovide asin Fig: 11 an inner heel element83 as a-separate unit resiliently mounted within the outery heel element 84 by a resilient material 88, such as a gum rubber or the like. In place of a resilient material, I may use a iiexible spring or spring biased hinge for connecting together the inner and outer heel elements.

To provide a surface with greater comfort to the heel of the foot, I may use in the various modifications described above a flexible innersole 88, shown in Fig. 11, which covers the inner and outer heel elements. The innersole 88 need not be xed to the outer heel to permit relative movement between the heel elements.

The resilient material 86, as previously mentioned, may be positioned between the inner and cuter heel elements of the various prior modifications as a sealing means to avoid the entrance in the shoe of moisture and foreign matter.

The inner heel element 83 may be slightly reduced in thickness as compared with the outer heel element to space the under surface of the inner heel element from the ground as at :B8 thus providing some resiliency for the os calcis when the foot is in a standing position.

VBy providing'my novel vmultiple shoeY heel having a heel element within a heel element flexibly The upper forwardedge of the outer heel elei ment supports the postero-inferior surface of the os calcis relieving the medial tubercle of the entire weight of the body and distributing the stress. In addition, the outer heel furnishes an additional point of support for the os calcis in a manner similar to the foot when walking unshod, Which adds to the stability of the foot when walking. The same balancing action occurs on the lower rear edges of the inner and outer heel Velements when they engage the ground forming multiple points of Y contact.

In providing an inner heel element for supporting the medial tubercle on which the foot may pivot, I can materially reduce the length of the rigid lever heretofore present in a shoe having a conventional heel. Consequently, I reduce the strain on the metatarsal and phalangeal bones, as well as reduce the strain on the leg bones and muscles during the action when initiating movement and when the extended foot contacts the ground. The foot need not be lifted as high for clearance as with the conventional heel and thus energy is expended.

The particular configuration of the inner and outer heel elements may be Varied to give the desired eiTect. By providing a posterior margin of the inner heel element normal to a plane containing the big toe, the natural hinge action of the medial tubercle in the unshod foot is imitated.

A plurality of inner or outer heel elements may be provided to give a varying degree of resiliency which will cushion the os calcis and absorb the shock of walking, in a manner similar to a cushion insert. The inner and outer heel elements can be connected integrally through the heel or sole, or may be made as separateV elements with a supplemental resilient connecting means.

I haveY thus described my invention, but I-dethat canbe employed to attain these objects and K accomplish these results.

I claim: Y

l. A shoe for the foot comprising innersole. outersole, and heelV sections positioned at the posterior region of the shoe for supporting the f medial tubercle of the os calcis, said sectionsdivided to form a Xed peripheral portion and a central movable portion the latter of which is positioned directly under the medial tubercle,

said movable portion moving with respect to the xed peripheral portion when the body weight is shifted during motion of the foot in normal gait.

2. The shoe of claim 1, wherein-the central movable portion is shaped in the form of a tongue, the fixed distal end of which is integral with the shoe. Y

3. The shoe of claim 1, wherein the xed peripheral portion completely encircles the movable portion. Y

4. The shoe of claim `1, wherein a ilexible material is positioned between the fixed peripheral portion and the movable central portion to permit sealing of the two portions during movement. Y

HARRY CHARLES STEIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Williams Feb. 5, 1946

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