US 487697 A
Description (OCR text may contain errors)
H. I'. EHLE.
No. 487,697. Patented Dec. 6, 1892Y liu/enfui' wtf/104930.?.
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UNITED STATES PATENT OFFICE.
HOMER F. EHLE, OF HELENA, MONTANA, ASSIGNOROF ONE-HALF T ALBERT y C. SHILLING, OF SAME PLACE.
SPECIFICATION forming part of Letters Patent No. 487,697, dated December 6, 1892.
Application filed February 12, 1892. Serial No. 421.301. (No model.)
To all whom it may concern,.-
Be it known that I, HOMER F. EHLE, a citizen of the United States, and a resident of the city of Helena, county of Lewis and Clarke, State of Montana, have invented a new and useful Improvement in Artificial Limbs, of which the following is a specication.
The object of my invention is to secure a natural movement for an artificial foot, ease of manipulation of the same by the wearer, and absence of shock or jar to the stump in walking by a construction whichshall combine simplicity with strength and durability.
The drawings and specification describe the invention as applied to an amputation between the knee and ankle; but it is equally applicable'to all other am putations above the ankle.
Reference is made to the accompanying drawings, which are made a part of this specification, in which similar letters refer to similar parts in all the figures.
Figure l is a side elevation of the whole mechanism, including thigh-socket, stumpsocket, and artificial ankle and foot. Fig. 2 is a vertical section of the ankle and foot lengthwise with the foot. Fig. 3 is a vertical section of the ankle and foot at right angles to the line of the foot. Fig. 4 is a vertical section of the metal joint in the ankle. Fig. 5 is a vertical section of the stump-socket looking at it from the rear. Fig. 6 is a vertical section of the stump-socket looking at it from the side.
The metal supporting-braces A A-one upon each side-are riveted or otherwise rmly attached to the thigh-socket B, the stump-socket C, and the ankle-piece D, and work with pivot-joints A at the knee. The ankle-piece D, which is preferably made of wood, is hollow throughout part of its length D', and is strengthened near each extremity by wrapping with wire d. The foot is composed of three sections. The lowest E is made of felt and is from two to three inches thick, according to the size of the foot. The middle section E is preferably made of wood and is placed so as to slope backward at an angle of above five degrees from the horizontal, and the uppermost section E2 is made of sponge rubber with its upper'an'd exposed surfaces of hardened rubber to resist wear. These sections are firmly glued together and line wire s is wrapped about the lower and middle sections near the heel. The foot is attached to the ankle-piece D by a metal knuckle-joint consisting of a cylinder F, solid in its central portion F and hollow at its ends. The bolts f f are firmly screwed into this central part F', and passing up through the apertures in the base of the ankle-piece D are secured in the hollow D by the nuts ff. The bolts g g are screwed into the pintles GG,which work in the hollow ends of the cylinder F, and passing through the slots g g pass through the wooden section E and are secured on its under side by nuts g2 g2. y Upon the cylinder F are two V-shaped iianges F2, which work in corresponding grooves E3 in the wooden section E', thus preventing any lateral movement in the joint.
In the back of the ankle-piece D is an aperture D2, through which passes the eyebolt h, secured at its upper end by a nut h and having an eye 77,2 at its lower extremity. Another eyeboltj passes up through the wooden section E', being secured at its lower end by the nut j and having an eye j2 at its upper extremity. A silk cord K is secured to the eye h2, and passing through the aperture Zin the rubber E2 and having some slack when the foot and ankle-piece are at right angles is secured to the eyej2. A flat steel springfm is fastened to the under side of the front end of the wooden section E by the bolts m and runs down, conforming to the shape of the foot over the instep and nearly to the toe of the felt section E. The stump-socket C is padded with any soft elastic material, preferably with sponge rubber covered with soft leather on its inside surface, as seen at n, wherever the bearing of the stump may come, according to shape and size of stump, and is an important feature in conjunction with the construction of the foot in securing ease and lack of shock to the stump.
The parts described as being made of wood may be made of any other suitable material possessing strength, firmness, and lightness, as aluminium. The rubber section E2 is made ICO about one-fourth inch thicker than the space between the base of the ankle-piece D and the Wooden section E', so that when the anklepiece and foot are secured together there is a one-fourth inch compression of the rubber E2, which will take up any play caused by wearing away of the rubber and give a firmer elasticity. The base of the ankle-piece D and the upper surface of rubber E2 are so shaped as to give a greater thickness of rubber in front of the ankle-joint, where most of the pressure will be, than behind.
The silk cord K is designed to act only so as to receive the strain in case of an unusual weight being thrown on the toe and thus to prevent wrenching and breaking of the anklejoint.
The spring m is not confined lo a flat spring, but may be of any suitable shape or construction,the object being simply to exert a downward pressure from above on the toe to prevent the toe turning up after the elasticity of the felt is weakened.
Having thus described my invention, what I claim, and desire to secure by Letters Patent, 1s-
An artificial foot composed of a lower section or sole-piece of feltconforming to the size and shape of the lower portion of the human foot, having a flat upper surface sloping backward at a slight angle and firmly attached to a dat middle section of woodor metal extending from the instep to the heel, having the same angular tilt, which is firmly attached in turn to an upper section of soft rubber which conforms to the shape of the upper part of the human foot up to andaronnd the ankle-joint, and which is thicker perpendicularly in front of the ankle-joint than in its rear, substantially as shown and described.
In testimony that I claim the foregoing as my invention I have signed my name, in presence of two witnesses, this 26th day of December, 1R91.
HOMER F. EI'ILE.
J AcoB J. STORER, EDWARD C. RUssEL.