US 817340 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
PATENTBD APR. 10, 1906.
4N T A N E V m M m 0V m NI 3 A M m AB IH BOP SIN 0P0 M, MM m P P A To all whom it concern.-
Be it known that I, RUnoLF.RsENxRA1vZ,
UNITED STATES Parana? ()FFICE.
, RU-DoLr RosENKnANz; or rn'rssuse, PENNSYLVANIA. ARTIFICIAL LINIB.
a citizen of the" United States, residing at Pittsburg, in the State of Pennsylvania, have inyented certain new and useful Im rovements in Artificial Limbs, of which t 'e following is a specification.
; My invention relates to artificial legs and Especially to the joint connecting the leg and the foot. The objects of the invention are,
l to provide a superior universal joint between the: main part of the artificial leg and its lower extremity; to provide a joint which will closely simulate in action the natural joint. of theankl; toavoid jar upon the-stump when the limb is brou 'ht in contact with the awing wherein-+- .5
ground an'd to simp ify and to strengthen and generally im rove the construction of artificial limbs. hese objects and other advantages which will hereinafter ap ear, I attain by-nieans of, the construction 1 lustrated in preferred forms in the accompanying Figure 1 is'a central vertical section through anartificial leg and foot having my improve ment -Fi es 2 jand 3 are-respectively, a central longliltu alsection, and a plan view, of the cus 'onmeinber of. the joint showing an alternate construction of the cushion, and i Figure is a central section of-amodified form of the limb for use when the footmhst be directly joined to the lower end of the':ar
tificial leg. I
Primarily I-avoid the use of hinges and sliding partsin the joint by providing a cushs the intermediate resistance of t e cushion block 9 which is preferably made of rubber. The bolt 7 extends through thiscushion block 7 and has a spherical head which works in a vide socket formed by two semi-spherical plates 11 and 11" both of which are screwed to the foot ortion 5.. In the socket may be proif some pockets of gra hite 12, or other lubricatingmaterial, and t e rubber cushion 9 is maintained in position by means of Dins Specification of Letters Patent.- 1 Application filed March 1, 1905. Serial l'o. 247.856;
Patented April 10,1900.
' '13 fixed in. the flat faces of 'the twowooden portions5'and'6l v The cushion block 9 has at its forward side a rtion 9" which is of denser structure of ru ber so as to provide greater resistance when'the pressure comes u on this portion by the tilting forward-of t e-leg portion 6 with respect to the foot portion 5, so that as the 'tilting proceeds the resistance becomes greater and greater in order to simulate the natural action .of the foot as much as ossible and make the joint most resilient at the rear. The? bolt 7' ordinarily is not required to move at-all since the cushion-block 9 allows for all variations of distance betweenthe surfaces of the leg portion and the foot portion, the leg moving about the ball 10 as a center. The 'bolt 7' may be kept tightand noise avoided by use of a rubber washer 14"plaoedunderthe lock nutat the top as shown.
In Figures 2and 3 is shown an alternate construction ,of the'cushion block 9 in which Y 'the eater iesistance'necessaryin the forwar portion is provided by an inserted block'l5 of harder rubber than the remainder of the'liod'y,having the same effect-as the denser portion 9"in.. the first form described.
In Figure 4 'isshown amodification .of the devices adaptedtotheus'e ofishchllimbs de-.
ed to accommodate-l cut ofi at theans'i I '85 k e, or just above1,'inwhic' case there is not much room in the le g'portion to fix the bolt 7 audit is therefore inverted andthe socket is placed on the uppe'i' side of the cushion block 9. As shown, the leg art22 has at the bottom a plate19 throng hich pass some riv- 'ets20,holdin the t .0 lates 17 and 18 which areuse to form t esocket for the head ofthe bolt. In this case also thebolt 7 is secured -by a lock nut andjunderneath it I there is a cushion of rubber 21in the portion 5, as in the first instance;
It will be seen th by this construction the footportion has a universal joint with.
the leg portion so that it maytilt laterally, and 'move forward and back, and in either 'motionit is resisted by the resiliency 'of the rubber, block 9; also that in the ordin' tilting motion of the leg in walking, the b ock 9 providesa heavier resistance on the front than on the back and this resistance will increaseiigigreater ratio by reason of the denser structure of the rubber between the two forward surfaces of the leg ortion 6 and the 'foot 5. Since thebolt 7' oes not have any no slidie motion in its sheath it is not required to be fubrieated and is entirely out of contact with any portion which mi ht make noise, being surrounded by a leat icr tube 8 and resting on the rubber washer, which also; maintains a snw fit of the hall lO'iu its; socket 12. It will be seen also that there are no parts which catigct out of order as the 1 parts are all held in proper position by the 1 weight upon the limb, and there are no movi ing parts except the revolution of the ball 10 l in its socket and this cannot make any noise I and requires only the lubrication that can be 3 sn )plied by the graphite inserts therein. It will also be seen that the parts are readily assembled or can be taken apart or can be easily interchanged, and the resistance of tlte joint to bending can bc t'efltltttttl by varying the amount of the dense portion of the rubber. in any motion of the foot the entire effect of weight of the leg-is met with a resilient cushion and all jarring is ptvoided. Other advantage of the structure will readily occur to those familiar with the'art.
Having thus described my invention and illustrated its use,.what l claitn as new, and desire to secure by Letters Patent, is the following:
1. An artificial limb comprising a leg portion and a foot portion and an intermediate rubber portion continuous in outer contour with the other two said portions and entirelv separating them, and a universal ball-andsocket joint connecting the two solid portions by parts passing through the rubber portion, substantiallv as descrtbed..
2. ln an artificial leg the combination with a leg port ion and a foot portion, and connecting means to hold them together each portion having a flat joint surface, of a rubber cushion between said portions 'ext-entlin" over the entire area of said flat surfaces am fixed in the leg portion, extending throughthe said rubber portion, a ball on the same and an engagin socket on the foot portion, said rubber cushion having the forward end made of denser rubber than the rest, to afford greater resistance to compression, substantially as described.
4. An artificial leg having ale g portion and a foot portion of solid material, an inter-- vening block of rubber entirelv covering the surfaces of said portions and being continuous with the other parts in'outline, whereby. there is no moving joint. between the footand leg portion, and a non-metallic sheath and a rod therein having a head making a universal joint between the foot and leg pprtions allow tng free compression of said ru ber pad, subst a ntially as described. I I
5. In an'artifieial limb a cushion for spacing at )art the foot and leg portions composed of soft rubber which has an integral forward part of it made more dense than the restto afford reater resistance at the forward side of the foot, substantially as described.
In testimony whereof I have hereunto. signed my name in the presence of the two subscribed witnesses. I
R UDOLF ROSENKRANZ'.