US1368348A - Artificial limb - Google Patents

Description

Patented Feb. 15, 1921.

46 [Tn/enter, a6 Z. Wu gzakaw ttor 'ey 67 I G. E. MOORE.

ARTIFICIAL LIME.

mwucmou FILED AUG-8. 1919.

y B w 4 w 5 a w 4 3 a w W 3 .movement in one UNITED STATES GEORGE E. MOORE,

PATENT OFFIQE.

0F PAT'EBSON, NEW JERSEY.

ARTIFICIAL LIME.

Application filed August a, 1919. Serial To all whom it may concern:

Be it known that I. Gannon E. Moore, a. citizen of the United States. residing at Paterson, in the count of Passaic and State of New Jersey, have invented certain new an useful Improvements in Artificial Limbs. of which the following is a full, clear, and concise description.

This invention relates to artificial limbs of the type embodying leg and foot portions connected together for relative movement, and a toe member hinged to the foot member; and has for its object the provision of improved means for controlling and limiting the relative movement of the various portions so as to provide an economical and durable artificial limb which will closely simulate the movements of a natural one.

The invention contemplates the provision of a leg portion having a foo-t member connected thereto for limited universal movement. a spring suspended stop to limit such direction and a nonstretchable elementto limit such movement in the opposite direction. The invention further contemplates novel means for limiting the relative movement of the toe and foot members which means comprises a rearwardly extending arm carried by the toe member and means contained within the foot for limiting the movement of the arm in either of two directions,

By employing an artificial limb construcb ed in accordance with this invention. the wearer may maintain his equilibrium when standing, when walking on a level or up or down a grade. and may even climb stairs or ascend a ladder bearing all his weight on the toe member? all-with the facility and sureness of a person possessing natural limbs.

One embodiment of the construction which secures these advantages over previously constructed artificial limbs is described in detail hereinafter and is illustrated in the accompanyi g drawings in which Figure 1 is a side elevation of an artificial leg made in accordance with my invention;

Fig. 2 is a bottom plan view of the foot member;

Fig. 3 is a. elevation showing the Specification of Letters ?atent.

Patented Feb. 15, 1921.

foot and ankle members and a fragment of the shank portion taken on the line a-a of Fig. 2;

Fig. 4 is a transverse section taken on the line b-b of Fig. 3;

Fig. 5'is a cross section taken on the line c-c of Fig. 3, showing the fore part of the foot member and showing the joint whereby movement of the extremity of said member is permitted;

Fig. 6 is a sectional view of a modified form of an ankle member; and

Fig. 7 is a bottom plan view of the structure shown in Fig. 6.

Referring now to the drawings in detail. in which like characters of reference are employed to designate similar parts throughout the several views.

7 indicates the shank portion of my device which is preferably hollowed out and shaped from a single block of wood to simulate the lines of the human leg. The top of this shank portion is provided with apertnred extensions 8, whereby said portion may be attached to an artificial thigh sec tion (not shown). or secured to the stump of the human leg. by means of straps or other suitable appliances (not shown).

In the present embodiment. these extensions comprise an arm 8" which is countersunk in a recess in the exterior of the shank portion and riveted or otherwise secured thereto. as shown at 8 the upper end being of a bifurcated formation to receive a complemental member on the thigh portion of an artificial leg and form a hinge connection therewith in such instances as may be necessary.

When these connecting members 8 are secured in position, the exterior of the shank portion is then preferably covered with rawhide. a thin fabric. or paper. or a like material. glued or cemented thereto. which overlies the outer surfaces of the portions 8 of the connecting members and gives the exterior of the shank portion a finish which possesses a skin'like appearance.

The lower end of the shank portion 7 is slightly reduced or inset to fit snugly or telescope within the upper part of the ankle member or section 9, which is preferably a casting of aluminum, or any other suitable formation approximating that of the human ankle.

In the formation or casting of this ankle member 9, I provide a wall It? partially co extensive with the interior dimensions of said member, the upper surface thereof proriding a platform 1U on which the base or lower end of the shank portion T is adapted to rest or bear. the lower part of said leg portion being of a substantially solid construction to add strength and rigidity thereto, as shown at 7*.

To add to the security of the connection between the shank portion 7 and the ankle member 9, the oppositely disposed ears 9 are formed on the interior of the ankle member 9 which carry bolts 11 passing through longitudinal bores in the lower part of the shank portion 7. the lower part of the e.- terior shank portion which is housed within the upper part of the ankle member 9 being formed with cut-outs, complemental to the said ears. lVhen the shank portion '5' is seated within the ankle member 9 and rigidly connected thereto by means of the securing nuts 12 on the bolts 11, to which access 15 afforded through the transverse openings 7 in the shank portion 7, it will be obvious that the shank portion 7 and ankle member 9 will be so joined as to be in if feet an integral member.

In the formation of the horizontally disposed wall 10 within the ankle member 9, it is made of a sutlicient depth or thickness to permit of the formation of. a. semi-spherical socket 13 in the under side thereof. faced with a Babbitt metal 13". this socket being apertured at 13 for the reception of a bolt 14, the head of whichis countersunk in the upper surface 10 of the wall 10, as shown in Figs. 3 and 4.

The foot member 15, having an integrally formed heel portion 15 and a relatively movable toe portion 16 connected thereto and functioning as hereinafter described, is in the form of a casting of aluminum or any other material which will possess the requisite strength and lightness, and is shaped to approximate the contour of the human member for which it is to form a substitute.

As will be observed, the contour of the upper part and edge of the said foot member 15 is complemental to that of the exterior of the lower portion of the ankle member 9 which fits or telescopes therewithin. as clearly shown in Fig. 3. Extending transversely of the foot member 15. adjacent to the top thereof, is a rib 15 whi h, in conjunction with the oppositely disposed inwardly directed cars 17 on the interior of said foot member. forms a support for the semi-spherical joint member 18. This latter member is preferably formed of an antifriction metal supported on a platform 19 to which it may be secured, so as to be substantially integral therewith by welding, brazing, or the like.

The platform 1) has extensions formed to rest upon the rib 15 and the ears 1?, and is firmly secured to these members by means of the bolts 20 and 21. Positioned on opposite sides of the platform ii) are U-shaped recesses 19 in which pieces of rubber or a similar resilient material. as indicated at 21, are inserted, this material forming a yielding support for the wood blocks 21 preferably formed of lignum-vitae or a similar wood which provides bearing surfaces for the downwardly depending ears 9 of the ankle member 9.

From the construction thus far described, it will be obvious that when the inlay 9 of the ankle member 9 is positioned within the foot member 15, the upon the bearing surfaces of the blocks 21. carried by the foot member 15. This will permit of a relative rocking movement of the ankle and foot members on a transverse axis, the extent of the movement of the forepart of the toot member toward the ankle member being limited by the non-stretchable cord 40 which is passed around the transversely disposed blocks .11 and 43 carried by the shank and ankle members respectively. The blocks 41 and 43 are preferably of wood, the former being supported in the oppositely located openings 42 in the wall of the shank member, while the latter is frictionally held within the spaced inverted U- shaped ribs 44 in the heel portion of the foot member 15. (flee Figs. 1 and 3.)

Assuming that the wearer of my improved artificial leg is performing the movements oi walking, it is obvious that as the shank member 7 is thrown forwardly incidental to the completion of the supporting movement of a step and preparatory to taking another step, the cord 40 will become taut and function to raise the heel of the foot member 15 out of contact with the supporting surface.

The movable toe member 16 continues in contact with the supporting surface to the limit of its movement on the hinged joint as hereinafter described. or until the supporting movement of the step is completed. As the limb is raised for the placement of the foot for the next movement of the step, it is apparent that means must be provided for maintaining the sole of the foot in a plane whereby the heel and ball of the foot member 15 will contact with the supporting surface in the same sequence as the corre sponding parts of the human member.

This is accomplished by the employment of a yielding floating connection between the ankle and foot members which consists of a pair of expansion springs 45 and 46 mounted on the rod 47. This rod has hearings in the ears 9 will rest freely messes boss 48 located in the heel of the foot member 15 and the lug 49 formed integral with the platform 19 in the ankle member 9, and is provided with an intermediate shoulder 50 forming a bearing surface for the upper end of the spring 45, the lower extremity of which is seated on the shoulder 48 of the boss 48. As will be observed, the upper end of the spring 46 is located within the recess 49 of the lug 49, while the opposite end thereof rests upon the shoulder 50 of the red 47.

The tensional resistance of the spring 46 is less than that of the lower spring 45, the two functioning with their cooperating elements to maintain the ankle and foot members in proper relation and control their action with a yielding or cushioning movement. The upward movement of the rod 47 is limited by the plate 52 extending transversely of the ankle member 9. This plate is of a harder material than that of the ankle member, steel being preferably used, to form a durable or wear-resisting bearing surface for the case hardened pin 51 set in the upper end of the rod 47. This pin, riding on the under surface of the plate which is inclined upwardly toward the rear of the ankle mem ber, provides for the relative movements of the foot and ankle members without interfering with the functioning of the springs and M5, as aforesaid.

hen the ankle member 9 is set or telescoped within the foot member 15, the joint member 18 registers with the complemental socket 13 of the ankle member 9, and the two members 9 and 15'may then be coupled together by threading the convex surfaced nut 22 on the depending end of the bolt 14. This nut 22 is of a size to conform to the interior dimensions of the joint member 18,

and, as is evident from the structure shown in Fig. 3, when the ankle and foot members have been united as explained, they will be capable of a relatively universal or rotary movement which will in eil'ect approximate that of the astragalo scaphoid joint of the human leg. This is accomplished by the cooperation of the ears 9' and their bearings and the components of the ball and socket joint or connection.

As previously pointed out, the toe portion 16 is movable relatively to the remainder of the foot member on a transverse axis, a portion of the forepait of the casting forming the foot member 15 having a semi-annular recess formed therein, as shown at 23, to receive a cylindrical sleeve 2-1, the said sleeve being immovably held in position within said recess by means of screws 25 or the like. It is manifest of course that in lieu of securing this sleeve in position as described, it may be welded or brazed to the casting, or the sleeve may be formed integral therewith.

The toe member 16 is formed with a semiannular recess 26 to provide a bearing surface which is adapted to register and engage with the projecting portion of the surface of the sleeve 24, the said recess 26 being held in movable contact with said sleeve by means of a screw '27 passing through the base of'the toe section 16 and seating in a plate 28 curved in cross section, which is positioned within said sleeve 24, said sleeve having a medially located elongated slot 28 in the wall thereof through which the shank of said screw is adapted to travel on the movement ofsaid plate. This hinged connection just described, in conjunction with the lugs 30 depending from the opposite sides of the forward extremity of the foot member 15, registering with the complemental recesses 31 on the toe portion 16, provides a; strong and substantial connection between the foot member 15 and the toe member 16, which is spaced forwardly of the vertical plane oi the line of cleavage between the foot member 15 and the toe portion 16. When the toe portion 16 moves upwardly in the completion of a step movement, as previously described, the underpart 16 thereof contiguous to the line of cleavage will be thrown downwardly out of alinement with the cooperating part of the foot member, and as theif'oot is placed for the supporting movement of another step, this under part 16 will precede the ball of the foot in making contact with the supporting surface, causing the toe portion 16 to oscillate on the sleeve and assume its normal position. From this it will be seen that the toe portion 16 will be capable of a resistant movement which is substantially similar to that of the forward part of the human foot in performing the movements incidental to walking and the like. The rear part of the toe member 16 is provided with an integrally formed arm 32 preferably of the configuration shown herein, the upper or free extremity of which is provided with a block of rubber or similar material 33 firmly secured thereto, which is adapted to contact with the upper surface of the transverse rib 34 of the foot portion 15, whereby the upward movement of the too member 16 is limited.

Teal-ford access to the hinged connection 15 and the toe the purposes of adjustment and lubrication, I preferably make the upper or to part of the toe member removable, as s own at 16, this section being located by means of the registering pins and apertures 16", the parts being securely fastened together by the screw 35. (See Fig. The base of the toe portion is preferably formed with a transverse recess 36 within which a piece 37 of leather, rubber, or a similar material, is inserted and frictionally held to form a yielding tread, the heel 15 of the foot member 15 being likewise cut out for the reception of a heel block 38 of any suitable yielding material.

It will be manifest from the foregoing description that an artificial leg constructed in accordance with my invention will not only be capable of movements which will closely follow those of the human leg in the act of walking for instance, but will also have a degree of movement at the ankle joint, whereby the functioning of this joint will accommodate itself to the general bearing of the user. This is a distinct advance in making an artificial leg an efiicient article of utility, as, heretofore, by reason of the construction of such devices, the wearer or user was compelled to readjust his hearing to the limited forward and backward movement of the ankle joint. Even then, after an artificial leg of prior constructions had been worn for a considerable time, it was diflicult and required considerable effort for the wearer to maintain his balance by reason of this defect. Furthermore, the toe action conforms to the movements of the toe and forepart of the human foot in walking, practically all objectionable stifi'ness and resnltant unsteadiness being eliminated.

My invention not only simulates the movements of the normal human limb, but its construction greatly facilitates the practising of those movements. The method of effecting the connection between the several movable parts, and of reinforcing and supporting one part through the medium of another, provides an artificial leg which possesses great strength and a degree of steadiness which will enable the wearer to maintain an upright position when at rest without any conscious efiort.

I claim:

1. An artificial limb having a foot embodying a toe member hinged thereto, a rearwardly extending arm carried by said toe member and means contained within said foot to limit the movement of said arm in either of two directions.

2. An artificial limb having a leg portion and a foot member, connected for relative movement, a toe member hinged to said foot member, an arm extending rearwardly from said toe member, means positioned within said foot member to cooperate with said arm to limit the movement of the toe member relative to said foot member in either of two directions, spring controlled means for limiting the movement of said foot member relative to said leg member in one direction and for moving said foot member relatively to said leg member in the opposite direction and a non-stretchable element for limiting movement in the latter direction.

3. An artificial limb having a leg portion and a foot member connected for relative movement and means for automatically returning the foot member to normal position upon the completion of a step, said means comprisin a rod, bearings for said rod carried by said leg and foot members, a shouldcr located intermediate the ends of said rod, a pair of springs on said rod, said springs being separated by and abutting against opposite sides of said shoulder, the other ends of said springs abutting against said bearing portions, an incline stop located within said leg portion for limiting the movement of said rod and control ling the movement of said foot relative to said leg portion in one direction and a nonstretchable element connected to said foot member and leg portion respectively to limit the movement of the foot relative to the leg in. the opposite direction.

4. An artificial limb comprising in combination an ankle member, a foot member secured thereto, a tubular bearing running transversely of said foot member intermediate the sole and instep portions thereof, a concave cylindrical bushing on said toe member to cobperate with said bearing, means for securing said bushing to said bearing, an extension of said toe member rearward from said bearing and a stop carried by said foot member to cooperate with said extension to limit the movement of said toe member about said bearing.

5. An artificial limb having a leg portion and a foot member, a semi-spherical babbittlined socket in the bottom face of said leg portion, a centrally-apertured semi-spherical anti-friction joint member to cooperate with said socket, a platform comprising a centrally-apertured semi-spherical shell portion secured within said foot member to support said joint member, means comprising a bolt passing through said central apertures and a nut cooperating therewith for maintaining said platform, joint member, and socket in coiiperative relation; a spring suspended stop to limit the movement of said foot member relative to said leg portion in one direction, and a non-stretchable element to limit said relative movement in the opposite direction.

GEORGE E. MOORE.

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