Improvement in artificial legs
US 37637 A
Description (OCR text may contain errors)
UNITE STATES arnNr OFFICE.
IMPROVEMENT IN ARTIFICIAL LEGS.
Specification formlng part of Letters Patent No. 37,637, dated February l0, 1863.
To all whom it may concern:
Be it known that 1, DUBOIS D. PARMELEE, of the city, county, and State of New York, have invented certain new and useful Improvements in Artificial Limbs; and I do hereby declare that the followin gis a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming apart of this specification, in which- Figure l represents a sectional side elevation of a leg constructed according to my invention. Fig. 2 is a front view of the same. Fig. 3 is a horizontal section of the saine, taken in the plane indicated by the line a x, Fig. l. Fig. 4 is an inverted plan of the same.
Similar letters of reference in the three views indicate corresponding parts.
The first part of this invention relates to the bucket or socket of artificial legs or arms intended to receive the stump; and it consists in the fastening of such bucket to the stump by means of atmospheric pressure in such a manner that the straps usually employed for this 4purpose can be dispensed with, and at the saine time a perfect tit of the bucket is attained.
The invention consists, further, in the peculiar construction of the knee-joint, which. is formed of two cylindrical rollersone being secured to the upper end of the large bone of the leg (tibia) and the other to the lower end ofthe thigh bone, (femur,) and each provided with a projecting lip or stopin combination with an elastic band or spring,lan'd with a double concave sector fitting between the two cylindrical rollers and held in place by metalhc clasps, which also form the bearings for the axes of said rollers, in such a manner that in walking the cylinders roll over each other, instead of rubbing, as is the case with other joints, and consequently the friction is considerably diminished, and at the same time, by the elastic band, the forward movement of the foot while walking is facilitated and uniform elastic pressure on the knee-pan is effected.
It consists, further, in dividing the toe-piece of'the foot in two or more distinct parts, each being provided with a separate joint and adjustable spring in such a manner that the toes can adapt themselves to the inequalities of the ground.
It consists, nally, in the arrangement of curved tails or shanks projecting from the toes on the under side or sole of the foot, in combination with suitable leatherstraps and springs and adjusting-clasp, in such a manner that the rigidity in the play of the toes can be regulated at pleasure, and that the toes are kept in the proper position to prevent interference when bringing the foot forward, and when the foot is brought down on the ground it presents a comparatively large and a yielding base, and enables the person wearing the leg to maintain his or her ba-lance with little labor.
To enable those skilled in the art to make and use my invention, I Will proceed to describe it with reference to the drawings.
A represents the bucket or socket to receive the stump of the amputated limb. The process by which this bucket is formed is some1 what similar to that by which dentistsform plates of hard rubber to conform perfectly to the roof of the mouth to be held there by atmospheric pressure. A form or mold of the stump is prepared in wax or plasterof-paris, (if of plaster-of-paris the inside ofthe mold should be oiled,) or gutta-percha may be einployed. Into this mold plaster-of-paris or fusible metal is cast, and thereby a perfect fac-simile or form of the natural stump is obtained. Around this form a sheet of indiarubber or gutta-percha compound prepared for hard vulcanization is tightly wound and made to smoothly conform to said form. The
whole is then firmly bound with wetted cloths 4 or embedded in plaster-of-paris, and thus prep'aredit is placed in the heater and vulcanized. After the vulcanization is completed the bucket is taken out and polished and mounted, as will be presently described.
Instead of this mode of obtaining the bucket,
the following process may be found practicable A hollow cone of vulcanite is formed, the inner circumference of which is the measurement of the stump to be fitted. A form or fac simile of the stump is next taken, as above described. The hollow cone is heated to 2120 Fahrenheit, or more, if necessary, and forced "lover the form of the stump and allowed to lcool upon it. rlhe form is next broken out.
is embedded in plaster-of-paris, and then the imetal melted out by immersion in oil or other liquid capable of sustaining the required tem- @perature The -bucket A is provided'with a l small faucet, a, inserted in its under side, and,
1f of plaster, or if of fusible metal, the whole when properly made by either of the above or any other suitable process, so perfectly does it fit the stump that on opening the faucet and forcing the stump into said bucket, and closing the faucet again, the pressure of the atmosphere will hold the bucket in its place till air is readmitted through the faucet. To obviate any inconvenience from insensible perspiration a dry sponge, cotton, wool, or small bag of fused chloride of calcium may be placed at the bottom of the bucket. rIhis bucket is fastened to that part representing the thighbone or femur B, when used for a leg above knee, or the stump of the arm or leg below knee by a metal ferrule, Z1. From this ferrule three or more metal bands, c, project, which are riveted to the bucket. By this arrangement it is perfectly easy to adjust the length of the limb with mathematical accuracy simply by shifting the ferrule b up or down on the artificial thigh'bone B until the bucket has attained the required position.
G is the knee-joint, which is formed of twol cylinders, d e, one being fastened to the lower end of the artificial thigh-bone B, and the other to the upper end ofthe artificial large bone of the leg or tibia l). Each of these cylinders is provided with a lip or off-set, d e', and they rotate on axles dit et, which have their bearings in metallic clasps f. A double concave sector, g, is placed between the cylinders d e, being retained in its place by pivots g', passing through the clasps f. The concave sides of this sector, which fit the surfaces of the cylinders d e, form the articial knee-pan and its edges by coming in contact -with the lips or (ff-set d e', confine the motion of the joint within the desired limits. An india-rubber band, 7.1 which is stretched ("v ever the convex surface of the knee-pan and around the supports B Dhas a tendency to straighten the knee-joint, and thereby assists the movement of the foot forward while walking, and at the same time a uniform elasticity is obtained by said band over the artificial knee-pan. rlhe cylinder d rolls on the surface of the lower one, e, and the friction created by the working parts of the joint is reduced to the smallest possible degree. The heel or ankle-joint E is formed of two pieces, t j, one of which is provided with a semispherical socket and the other with a corre sponding prominence, as clearly shown in Fig. l of the drawings. This prominence t-s perfectly the socket, and each ofthe two pieces t' j is provided with flanges projecting beyond the socket and prominence, whereby the movement or play of said parts in either direction is confined between limits, such as may be desired bythe constructor. rlhe upper part, t', of the heel-joint is fastened to the lower end of the articial tibia,
and the lower part, j, of said joint is screwed or otherwise firmly secured to the foot-piece F, and the two parts t' j are fastened together by an india-rubber tube, 7u, of proper thickness and strength to attain the effect desired, which is stretched over the same and secured to each part by tying with cord or in any other desirable manner. The foot-piece F corresponds to the bones of the instep and heel-hone ofthe natural foot. Its front end, Z, is rounded off and forms the fulcrum for the piece G. This piece is divided into three (more or less) distinct parts, m m m, one of which corresponds to the large toe, and each of the others to two of the other toes, as clearly shown in Figs. 3 and 4 ofthe drawings. These toe-pieces are held in place by bands n, ofleather or other inelastic but flexible material, fastened by means of screws or any other desirable means to the under side of the same an d of the foot-piece, and by elastic bands 0, of india-rubber or any other suitable material, fastened by any convenient mode to the upper surface and that of the footpiece, as clearly shown in Figs. 1,3,and 4r. rllhe inner ends ofthe elasticbands o pass through ametal clasp, ya, so as to admit tightening or loosening,accord ing to the requisite rigidity desired in theplay of the toes. By the action of these elastic bands or springs the points of the toes are thrown up so as to prevent interference when bringing 4the foot forward, and their position is regulated by the length of the leather'bands n, which bear against the stems or tails mit', eX- tending from the toe-pieces m m m below the point of the foot-piece F, as shown in Fig. l of the drawings. lf the weight of the body is upon the front of the foot, by the action ofthe tails mt the toe-pieces are turned down and a large base is attained, thereby enabling the person wearing the leg to maintain his or her balance with little labor. By the division of the toes they are enabled to adapt themselves to an unequal surface. The heel H is covered by an elastic pad, to prevent any jarring in the act of walking. The case for this leg or arm may be made of cork, papier-mache, or any other suitable material, but that form I would recommend would consist of a leather tube cut into the shape ofthe limb, sewed up, and small hoops of steel springs placed and fastened on the interior at about three inches apart to give form to the case, and at the same time preserve its flexibility. Such a case might be fastened by hooks to the bucket at the top, and when used for a leg be made to connect at the 'bottom with the leather boot, inclosing the foot.
The principal advantages of my artificial limb are that it can be fastened to the stump without the use of straps around the waist or shoulder, and it requires no tedious fitting. With limbs of the ordinary construction the patient is required to sit and wait for repeated trials, while the artisan scrapes away the Wood to t the socket, and this operation is hardly ever attended with perfect success until after several trials of the leg. Furthermore, my knee-joint works with the least possible friction. It is simple, cheap, durable, and not liable to get out of order, and the toe- A piece of an ordinary leg presents not quite one-half the area for basal support that is attained by the peculiar arrangement of the toepiece in my leg.
Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-
1. Fastening the bucket A of an artificial limb to the stump by means of atmospheric pressure, substantially in the manner specilied.
2. The knee-joint C constructed of two cylinders, d e, clasps f, double concave-sector g, and elastic band h, all arranged and operating substantially in the ina-nner and for the purpose herein shown and described.
3. Dividing the toe-piece G in two or more v distinct parts, substantially as and tor the purp'ose set forth.
4. The arrangement of the stems or tails n mit, projectingfrolnthe under side of the toepieces mm fm, in combination with the bands u, of leather or other suitabe material, and with the elasticbands 0, afjustable by a metal clasp 19, or its equivalent, ill constructed and operating substantially in the manner and for the purpose described.
DUBOIS D. PARMELEE. Witnesses:
TIMOTHY SHINE, M. S. PARTRIDGE.