Improvements in Artificial Legs.
Year: 1888

page_text: Date of Application, 24th Aug., 1888
Specification Accepted, 28th Sept., 1888
COMPLETE SPECIFICATION.
Improvements in Artificial Legs.
1, CHANCY ADELMER FREES, of 766 Broadway, New York, County and State of
New York, United States of America, gentleman, do hereby declare the nature of
this invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
This invention relates to an artificial leg and more particularly to the ankle and
knee joint thereof.
Fig. 1 is a longitudinal central section of the leg.
Fig. 2 is a top view of the foot.
Fig. 3 is a bottom view, and
Fig. 4 a top view of plate a.
Fig. a side view of the bar
Fig. 5 a side view of the holt /*.
Ir.
and
A, is an artificial leg made of the usual form and entering a socket in the foot B.
The joint upon which the leg may rock backwards and forwards and also sideways,
consists of a plate a, made of cup shaped form, that is, convex on the bottom and
concave on top, or rice versa. This plate is attached rigidly to the lower part of leg A.
The convex lower part of the plate a, constitutes a ball and is received by a socket b,
in the foot, the whole constituting a ball and socket joint. The concave upper part of
the plate a, constitutes a socket and receives a ball c, attached to a short arm d, of a
fork, the longer arm e, of which passes through a slot of plate a, and thence down-
wards, to the sole of the foot, to which it is fastened by nut. The upright arm g, of
the fork connects with a spring or elastic web h, which is secured to a hook i, attached
to the leg or thigh.
It will be seen that a ball and socket joint is formed on each side of plate a, and
that thus the foot may rock in any direction between the parts b, c, on the one hand,
and the part a, on the other hand. or vice versa.
The spring or elastic web h, will expand sufficiently to permit the rocking of the
foot and it will bring the foot into its proper position under the leg, as soon as any
lateral, or back or forward strain on the foot is removed.

page_text: The upper part of fig. 1 shows the construction of a knee joint, with artificial legs
employed in thigh amputations.
The spring, heel tendon 71, and check cord 2, are attached to a hook, or to the
pin i, traversing the thigh D. The thigh D and leg A, are connected by a transverse
pivot pin or screw bolt, having a tapering head or thimble 1, at one end and
entering a threaded tapering socket ', at the other end. The bolt passes through
two braces, projecting upwardly from the lower leg A, and through the
lower portion of the upper leg D. The head, and socket ', are received by
recesses in the sides of the lower end of upper leg D. By tightening up the
bolt, or the socket 7, the joint between the parts A, D, may be adjusted when
worn.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is:
1. The combination of leg A, and foot B, with the plate a, and with balls and
sockets above and below said plate, substantially as specified.
2. The combination of leg A, and foot B, with bulged plate a, and with a forked
bar, provided with ball and with spring substantially as specified.
3. The combination of a bulged plate a, forming a ball on one side and a socket on
the other, with a concave bearing and with a ball on opposite sides of said plate and
operating in conjunction therewith, substantially as specified.
4. The combination of leg A, and thigh D, with a bolt, having conical heads
or sockets at either end, to constitute an adjustable joint, substantially as specified.
Dated this 24th day of August 1888.
HERBERT J. ALLISON,
Agent for the Applicant.