Year: 1886

page_text: I, WILLIAM ROBERT LAKE, of the firm of Haseltine, Lake & Co, Patent Agents,
Southampton Buildings, in the County of Middlesex, do hereby declare the nature
of my 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 horse shoes having the inner edges of the undersides
bevelled to prevent the adhesion to the shoes of snow, ice, or clay; it relates also
to horse shoes having sockets adapted to hold removable calks; and also to the
calks themselves.
One object of my invention is to provide a horse shoe that shall, while having
the peculiar concaved or bevelled inner edges of the wearing surface, also be so
made as to leave enough breadth of the metal at the toe and heel to afford proper
wearing surface, and also to allow sockets to be made for the insertion of removable
calks. My invention has further for its object the construction of a socket in the
shoe and of the stem of the calk in such manner and form that the latter may be
tightened in the socket in the first instance, and after it has worn loose; and still
further to provide means for securing a hardened metal core or plug in the wearing
face of each calk.
My invention consists in a horse shoe cut away underneath on a chamfer part
way along the inner edge of each of its sides and on a different chamfer or steeper
slope near the heels and toe; in details of the construction and combination of the
peculiarly threaded calk socket in the shoe and the cylindrical calk having a
threaded stem; and in the calk having a hard centre or core and the peculiar
means of securing the latter within the calk, all as more particularly hereinafter
described.
In the accompanying drawing
Figure 1 is a bottom view of a horse shoe embodying a feature of my
improvement.
Figure 2 is a view in cross section on the line x - - x figure 1.
Figure 3 is a view in cross-section through the side of the shoe on the line -Y

page_text: DOCUEC
the calk socket, showing the calk in place.
Figure 5 is a sectional view through the socket, the calk being removed.
Figure 6 is a sectional view, drawn to an enlarged scale, of the threaded calk
showing one form of hardened core.
Figure 7 is a view in central longitudinal section of a horse shoe calk showing
one form of core socket.
Figure 8 is a side view of one form of the core or plug adapted to be secured in
the core socket shown in Figure 7, and having part of its upper end broken away
to show its recessed end.
Figure 9 is a view in central longitudinal section of a horse shoe calk showing
the hardened core or plug as secured in place within the calk.
Figure 10 is a view in central longitudinal section of a horse shoe calk showing
an alternative form of core socket.
Figure 11 is a view of the form of core used with this latter form of calk.
Figure 12 is a view in central longitudinal section of a calk with the plug or
core secured in place in the calk socket shown in Figure 10.
Figure 13 is a view of a core or plug with the end split and a wedge inserted;
which forms alternative means for securing the plug within the socket in the calk.
a denotes the toe portion of a horse shoe that is made of ordinary material, and
bb the two sides of the shoe. The wearing surface of the shoe, as shown in
Figure 1 of the drawings, is broad at and near the toe, is narrowed along each side,
and is broadened again at each heel.
A concave chamfer is made on the inner edge of the underside of the body of the
shoe, from a¹ to b¹, and from a to b', which removes superfluous metal without
materially lessening the strength of shoe, enough material being left on the under
side of the shoe for the creases fand the nail holes, and for the wearing surface,
or to hold metallic càlks in the broader part of such wearing surface.
At the toe, from a¹ to a³ the concave chamfer is made on a different angle, with
a steeper slope with reference to the plane of the bottom of the shoe than the
chamfer along the side portions of the shoe, as shown in Figures 1, 2 and 3 of
the drawings, the under face of the shoe being left nearly of the full width of
the body of the shoe at the toe and at the heels, in order to afford a large wearing
surface and metal enough to hold the calks c c.
This double concave chamfer prevents snow and other adhesive. substances from
packing, in, or adhering to the bottom of the shoe, and, to a great extent, the
picking up and throwing of gravel; at the same time the weight of the shoe is
lessened without taking away from its wearing properties and sufficient metal is
left at the proper points to permit the making of sockets for the insertion of calks
when required.
The broad idea of cutting the inner edge of the bottom of the shoe on a bevel
or chamfer to prevent clogging and balling within the shoe is not new, the improve-
ment residing in the chamfer of different angles of slope of several parts in
passing from the heel on one side to the toe and around to the heel on the opposite
side.
The calks c are secured in the threaded calk sockets d in the shoe by means of a
thread cut upon the stem of the calk. Although any calk may be used with the
shoe having the above described improvements, my improved calk is formed with a
cylindrical body having a wearing face e and a threaded stem e², and it is
preferably without any shoulder other than that formed at the termination of the
thread at the base of the threaded stem.
The great difficulty with removable calks that have been held in horse shoes by
means of a threaded stem fitting a threaded socket in the shoe, prior to my
invention, has been that the thread in the socket has been uniform in depth and
size throughout, whether such- thread was cut in the walls of a cylindrical or
tapered hole. This regularity of the thread prevents any tightening of the calk
after it had once become loosened by wear. In the cylindrical form of the calk
7

page_text: the wear was practically uniform between the threads on the stem and those in the
Bocket throughout its length and the tightening up of such a calk when loosened
was impossible, even when it had a bearing shoulder that rested on the bottom of
the shoe; and in the tapered form of stem and socket, the attempt to tighten the
calk in place tended to strip the thread at the upper end, and a slight backward
turn of the calk was then sufficient to completely free it so that it would drop
from the socket.
In order to remove these difficulties found in prior devices in the practice of my
improvements, the thread is cut in the socket in the shoe by means of a tap that
bears a succession of teeth that diminish in height from the upper end towards the
point of the tap, the bottom of the thread of such tap being so cut as to leave a
body of uniform diameter, practically cylindrical.
The socket originally is a cylindrical hole and is left after cutting with such tap,
with a thread having its top substantially equidistant from the axis of the socket
throughout, and the bottom of the thread at a gradually decreasing distance from
the axis in passing from the lower to the upper side of the shoe.
The stem of the calk used in such a socket is cylindrical and has a thread of
substantially uniform height that will fit into a threaded socket in the shoe of the
same gauge as the thread on the stem, and conform to it so far as the thread in the
socket is completed.
The result of an attempt to screw such a cylindrical calk in the above described
socket in the shoe, is that the complete thread on the calk will be upset and will
bind in the socket and hold the calk firmly in place. After this calk has become
loosened in such socket by wear, the loosening however being resisted by the whole
length of the threaded parts of the calk and socket that are in contact, it may be
again tightened by simply screwing it further in by means of a pair of tongs or a
wrench, as the thread in the socket decreases in pitch towards the top of the shoe.
This tightening may be repeated a number of times without destroying the threads
and preventing the substitution of a new calk when one has been worn out.
This peculiar combination of threaded socket and threaded calk stem affords a
safeguard against accidental driving of the calk through the shoe into the hoof,
and a space is always left in the upper part of the socket when the calk is first
fastened in, as this space allows for the readjustment of the calk in tightening it as
described.
The calk may be wholly made of any single metal, as iron, so far as the above
described portion of my invention is concerned, but it is preferably made with a
central core or plug that may extend through the calk, but is preferably secured in
a socket in the wearing face of the calk in position as shown in Figure 6, where
the inner end of the plug stops short of the plane of the under face of the shoe.
The body or shell of the calk is preferably made of iron or soft steel and the core,
or plug h is of hardened steel, the latter being inserted in the socket g (formed by
drilling, or otherwise) in the body of the calk, and it is held therein by welding it
thereto, by adhesion to the body of the calk or by any other suitable method.
The particular advantage of having the core or plug of such length that it does
not extend through the body of the calk is, that the end wall of the socket
resists the thrust of the core, and the welded or adhesive joint between the lateral
surface of the core and that of the socket is to a considerable extent relieved from
strain.
This method of construction has a special advantage when a blunt calk is desired,
for the socket does not extend into the threaded portion of the shank, and, there-
fore, there is afforded the full strength of an iron shank with a large wearing surface
of steel,
If a blunt calk is made with a core extending completely through it, the thin
shell of iron in the calk which surrounds the steel core in the shank is liable to be
cut through in forming the thread on the calk and such a calk will lack strength
at that point because of the brittleness of the steel which is thus deprived of the

page_text: tougher iron support; and even with a core of the smaller diameter as in the self-
sharpening calk, in which the core extends completely through it, the calk is liable
to break off after but little wear, owing to the strain which comes upon the calk at
the point where it enters the shoe, and when such a stem is left in the shoe it is
very difficult and almost impossible to remove it without destroying the threaded
socket in the shoe.
It is desirable to make a calk of steel throughout, if this could be done, on
account of its wearing properties, but the danger of breakage prevents the use of
such a calk. A further advantage of a calk which has a core extending but part
way through it is that when the calk has been well worn down the remaining
portion is of metal sufficiently soft to be firmly grasped by a pair of tongs, or it
can be easily bored through for the reception of an angular tool that may be used
to unscrew the threaded stem without injury to the thread in the socket of the
shoe.
f
There are many methods of securing the core in the wearing face of the calk in
addition to welding or soldering, and several of these methods are illustrated in
figures 7 to 18 of the drawings, and the letter e denotes the body of the calk, that
has a threaded stem e³ and a socket g opening towards the point of the calk, prefer-
ably formed by drilling. This socket has an enlargement g¹ at the bottom greater
in diameter than the other part of the socket, and is formed in any convenient
manner, as by means of an expanding drill.
The letter h¹ denotes a core or plug which is made of harder material than the
body of the calk, and is cylindrical in form, and of a diameter that makes it fit
closely in the socket.
This core has in one end a cavity h³, deeper at the centre than towards the edges,
so that when the core is forcibly driven into the socket the thinner edge at this
end strikes the end wall of the cavity and is thus upset and pressed outwards so as
to more or less completely fill the enlargement g¹ at the bottom of the socket.
This core is preferably made of steel, tempered throughout its length, and the
temper drawn from the end bearing the cavity so as to enable that end to be
expanded into the socket in the manner already described.
This core may be left blunt on the outer end or it may be sharpened, and this
sharpening may be done either before the core is fixed in place in the body of the
calk, or after such operation. In the former case a conically recessed end may be
used in driving it into such socket.
An alternate and equivalent means of holding a core in place in the body of the
calk, is illustrated in figures 10 and 12, in which a central projection i is formed on
the end wall of the socket in such position that when a cylindrical and blunt ended
core, such as is shown in figure 11, is driven into place in the calk its inner end
will be expanded and pressed into the enlargement of the socket in practically the
same manner as before described.
Another equivalent means of expanding in the inner end of the central core is by
cutting a slit or a notch of a limited depth in the end of the core, fixing in such slit
the narrow edge of a short wedge and then driving the core firmly into the socket,
see figure 13.
The particular advantage of these latter described methods of holding a core in
place in the calk is due to the fact that such a core is not loosened by wear, but is
more firmly held in place as the calk is worn.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim as the invention communicated to me is :-
FirstA horse shoe cut away on the underside on a concave chamfer along the
inner edge of each of its sides, and around the inner edge of the toe on a different
concave chamfer, joined to the chamfers on the sides, substantially, as, and for the
purpose, described.

page_text: Second: A horse shoe calk consisting of a metallic body or shell having a
threaded shank and a plug of harder metal, as steel, secured in a socket in the
wearing face of the calk, the core being enclosed laterally by the shell, but ter-
minating at a short distance from the plane of the underface of the shoe when the
calk is screwed up to place in a horse shoe, all substantially as described.
Third: In combination with a horse shoe having a threaded calk socket with
the top of the thread substantially equidistant from the axis of the socket and the
bottom of the thread at a gradually decreasing distance from the axis in passing
from the lower to the upper side of the shoe, a removable calk having a cylindrical
stem with a thread of substantially equal height throughout its length, as, and for
the purpose, set forth.
Fourth A removable horse shoe calk having a socket opening towards the
point of the calk with a lateral enlargement at the bottom of the socket and a core
with its inner end expanded into such enlargement, all substantially as described.
HASELTINE, LAKE & Co.,
For the Applicant.