Year: 1888

page_text: I, WILLIAM JAMES DONALD, of Tunnel City, in the County of Monroe, and State
of Wisconsin, United States of America, Physician, do hereby declare the nature of
this invention to be as follows:-
This Invention is an improvement in that class of crutches which have an
elastic foot and a spur, either of which may be adjusted for use alone, as conditions
require.
The attachment consists of a metallic socket piece adapted to receive the lower
end of the crutch which is of taper form. This socket piece is screw-threaded and
terminates in a spur or pointed end to be used on slippery surfaces. Upon the socket
piece an elastic buffer or foot of rubber or other suitable material is secured, the said
buffer being formed with a hole through which the projecting end of the socket pieco
passes. The buffer is provided with a top plate having a nut which screws on the
socket piece, so that the buffer can be adjusted to allow the spur to project beyond
the buffer or be withdrawn, as desired.
The buffer is preferably of polygonal form, to facilitate its adjustment on the socket
piece.
W. J. DONALD.
By A. M. & Wm. Clark,
53, Chancery Lane, London,
Patent Agents.

page_text: I, WILLIAM JAMES DONALD, of Tunnel City, in the County of Monroe, and State
of Wisconsin, United States of America, Physician, 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 is an improvement in that class of crutches which have an
clastic foot and a spur either of which may be adjusted for use alone as conditions
require.
The Invention consists in an attachment for the lower end of a crutch constructed
and arranged as hereinafter described and claimed.
Reference is to be had to the accompanying drawings forming a part of this specifi-
cation in which figure 1 illustrates the invention attached to the lower end of a crutch.
Figure 2 is a vertical section on the line a figure 1. Figure 3 is a plan view of
the elastic foot or buffer detached; and figure 4 is a plan view looking at the under
side of the attachment. Similar figures of reference indicate corresponding parts in
all the views.
The attachment consists of a metallic socket piece 1 having a socket 2 which is
adapted to receive the correspondingly shaped end 3 of the lower end 4 of a crutch
that is secured in place by a screw 5. The socket piece 1 is formed with a screw-
threaded projection 6 having a pointed end 7 which serves as the spur for the crutch
to be used for slippery surfaces. Upon the projection 6 is mounted an elastic buffer
or foot S of rubber or other suitable material formed with a hole 9 in line with a
screw-threaded hole 10 in a lug 11 inserted in the upper part of the buffer 8, and
depending from a metallic plate 12 secured by screws 13 to the top of the latter.
The screw threaded lug 11 engages the screw-threaded projection 6 and by this means
the buffer 8 is adjustable upon the projection 6 so that by screwing it up, the spur 7
will project through the lower end of hole 9 for use, and by unscrewing it the spur 7
will be withdrawn into the buffer 8 whereby the latter will serve as an elastic foot
for the crutch. The buffer 8 is preferably of polygonal form by means of which
the buffer S will not have to be handled in interchanging it for use with the spur 7,
it only being necessary to extend the crutch and rest the buffer 8 on its side and
then by rolling it on the ground or a floor to screw or unscrew the buffer on the
projection 6 thereby projecting or withdrawing the spur 7.
By means of this invention, a crutch attachment is provided which is simple in
construction and by means of which the foot of a crutch can be readily converted
into a spur or an elastic buffer.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the sanie is to be performed, I declare that what I
claim is :-
1. An attachment for crutches, consisting of a piece to be attached to the lower
end of a crutch formed with a screw-threaded projection having a pointed end, an

page_text: elastic buffer having a perforation through which the screw threaded projection
extends and a screw threaded connection by means of which the buffer is vertically
adjustable on the screw threaded projection, substantially as shewn and described.
2. An attachment for crutches, consisting of an attaching piece formed with a
screw-threaded projection having a pointed end and a polygonal elastic buffer
screwing on to the screw-threaded projection, extending through the buffer and
vertically adjustable over its point, substantially as shewn and described.
3. An attachment for crutches, consisting of the apertured polygonal elastic
buffer 8, provided with plate 12 having threaded hole 10, substantially as shewn and
described.
4. The combination with the threaded end of a crutch having spur 7, of the
apertured polygonal elastic buffer 8 provided with plate 12, having threaded
hole 10, substantially as shewn and described.
W. J. DONALD.
By A. M. & Wm. Clark,
53, Chancery Lane, London,
Patent Agents.