IMPROVEMENTS IN DIGGING MACHINERY
Year: 1855

page_text: LETTERS PATENT to Omrod Coffeen Evans, Doctor of Medicine, of the
City of New York, United States of America, for the Invention of
PROVISIONAL SPECIFICATION; left by the said Omrod Coffeen Evans at
the Office of the Commissioners of Patents, with his Petition, on the
17th December 1855.
I, OMROD COFFEEN EVANS, Doctor of Medicine, of the City of New York,
United States of America, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN DIGGING MACHINERY" to be as follows:-
The machinery consists of a truck or cart supporting a framework, in which
revolves a series of drums or broad-faced wheels side by side, each carrying an
endless belt or chain upon which a series of spades or digging forks is placed.
The operation of these is such, that as the machine is drawn over the ground
each spade is driven into the ground gradually and in successive order, so as
simply to pierce the same without breaking in the first instance. The up-
heaving or turning of the sod is performed only at the time of leaving the

page_text: ground. By means of this peculiarity, not only a great surface and depth
may be dug over in a short time, but this may also be accomplished at a
moderate expenditure of power. The frame of the machine is open in the
interior, and hung upon two truck wheels, suspended from the outside upon
short axles, but in such way as to permit the raising and lowering of the frame,
together with the series of drums and spades attached thereto. Upon the
sides of the frame is a dovetailed groove, into which a strong sliding plate
fits; from this project the axles on which the wheels are hung. From the
sliding plate and on each side an upright rises, having a cross piece at top
attaching the two together; two rods or posts permanently attached to the
framework rise on each side. A lever of the first class has its fulcrum on
the top of the upright, and a weight attached at the short end, the power
being applied to the lever by a windlass and pulley. When the frame is to be
raised so as to lift the spades clear of the ground, winding the cord upon the
pulley raises one of the posts or rods, and with it the frame and its attach-
ments; the upright being firmly affixed to the axis of the truck wheel, the
dovetails will glide along the slides which remain in position. It is proposed
to place several of the spade drum wheels side by side between the frames.
The frame is provided with pulleys, over which passes the endless chain hold-
ing the spades or spading forks; one roller is placed in the fore part of the
machine, and is suspended above the ground at height a little greater than
the length of a spade tooth; the lower surface of one of the drum wheels
rests upon the ground, as does also the other pulley. From the former of
these two pulleys on the frame to the lower surface of the drum the spade
chain forms an angle with the ground, while from the drum wheel to the
second pulley on the frame it passes parallel thereto. It has been remarked
that the spades enter the ground by a gradual 'pressure, and also by a direct
thrust, even although the machine is all the time in a state of progressive
motion. To accomplish this, the teeth are curved with a certain curve, having
a radius from near the point of contact of the drum with the ground extend-
ing to the surface of the pulley; and this is a distinguishing feature of my
machinery, that each spade remains stationary or nearly so over the spot it is
to operate upon until it has performed its work, the machine rolling over
the spades.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Omrod Coffeen Evans in the Great Seal Patent Office on
"the 14th June 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, OMROD
COFFEEN EVANS, Doctor of Medicine, of the City of New York, United States
of America, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventeenth day of .December, in the year of our
Lord One thousand eight hundred and fifty-five, in the nineteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Omrod Coffeen Evans, Her special licence that I, the said Omrod Coffeen
Evans, my executors, administrators; and assigns, or such others as I, the.
said. Omrod Coffeen Evans, my executors, administrators, and assigns, should
at any time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for "IM-
PROVEMENTS IN DIGGING MACHINERY," upon the condition (amongst others) that
I, the said Omrod Coffeen Evans, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said Invention,
and in what manner the same was to be performed, and cause the same to be
filed in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Omrod Coffeen Evans, do hereby declaro
the nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, reference being had to the Drawings hereunto annexed,
that is to say:-
My Invention consists in an improved machine for spading or breaking up.
the earth preparatory to planting. The machine consists of a truck or cart
supporting a framework, in which revolves a series of drums or broad-faced
wheels side by side, each carrying an endless belt or chain, and upon which a
series of spades or spading forks is placed. The operation of these is such,
that as the machine is drawn over the ground each spade is driven into the
ground gradually and in successive order, and so as simply to pierce the same
without breaking in the first instance. The upheaval or turning of the sod or
earth is performed only at the time of leaving the ground. By means of this

page_text: peculiarity, not only a great surface and depth may be dug over in a short
time, but that may be accomplished at a moderate expenditure of power.
Figure I. represents a side view or elevation of the machine. At A is
one side of a strong frame, open in the interior, being hung upon two truck
wheels B, suspended from the outside upon short axles, but in such way as to
permit the raising and lowering of .A; together with its series of drums and
spades attached thereto. Upon the sides of A there is a dovetail groove' (c),
into which a strong sliding plate (d) fits; from this the short axles on which
the wheels B are hung 'project. From the sliding plate a post E also rises on
each side, as shown,..having a cross piece at the top connecting the two
together for. solidity. Two other posts arise from each' side, but are perma-
nently attached to the frame pieces A, as shown at F. At G is a lever of the
first class; its fulcrum is upon the top of the post E; the weight F is attached
at the short end, and the power applied by means of a windlass and pulley
at H. When the frame: A is. to be raised so as to lift the spades clear of the
ground, winding the cord' upon H raises F, and with it the frame A and its
attachment; the post E being firmly affixed to the axis of B, the dovetails (c)
will glide along the slides (d), which remain in position. This raising and
lowering of the drums within the frame may be effected by any suitable train
of movements instead of that I have described, as I am aware that' those may
be advantageously varied by a skilful mechanic, in accordance with the size
and weight of the machine employed. A set of gear wheels, worked by a
winch placed in a situation convenient to the operator, will be a desirable,
method. At I is represented one of the spade drum wheels. In each machine
it is proposed to place several side by side between the frames A. At J and K
are two púllies placed in the frame respectively, as shown. The endless chain
holding the spades or spading forks passes over these in the manner repre-
sented at L, the spades being represented by the letter (m). The roller J is
placed in the fore part of the machine, and is suspended above the ground at
height a little greater than the length of a spade-tooth. The lower surface
of the drum I rests upon the ground, as does also the pulley K. It will now
be seen, that from the pulley J to the lower surface of the drum the spade.
chain forms an angle with the ground, while from the drum wheel to K
it passes parallel thereto. It has been remarked that the spades enter the
ground by a gradual pressure, and also by a direct thrust, even although the
machine is all the time in a state of progressive motion. To accomplish this,
the teeth are curved with a certain curve, having a radius from near the point
of contact of the drum I with the ground, as at X, extending to the surface of
the pulley J; and it is a distinguishing feature of my machine, that each spade
a

page_text: remains stationary or nearly so in the spot it is to operate upon until it is to
perform its work, the machine rolling over them. Thus, as in the progress of
the machine the spades are brought round by: the revolution, of the drum I,
a spade will come into position as at (m) the moment it has passed' the
under side of J; here; it remains stationary, while, as the machine advances,
the drum. I; rolling upon the endless chain, forces the portions between X and
J. toward the ground, so that when the drum arrives over (m); the spade will
have been inserted to its full depth, as shown by the spade at; (m'). In fact,
that portion of the flat chain L which is upon the ground forms a roadway or
track for the drums. When, however, the small pulley. K arrives. over the
spade (m), now supposed to be in the position of (m"), this. pulley K also
travels as it were along the endless chain, so that at the point of contact
where the chain takes a turn upward, that point will describe a portion of a
cycloid, and the spade (m") will be tranferred from the vertical position to a
horizontal one, turning at that time upon the axis of K as a center, and thus
by necessity upheaving the earth, as the spades or forks cannot be released
without doing so. The operation of one being 'described; that of the other
drums would be a mere repetition. It may not always be desirable that the
spades or forks should be curved in the precise manner herein-before described,
and if made nearly or quite straight they will in some earth's penetrate better,
and will then only be required: to move a little more through the ground:in a
forward direction as the machine progresses, but this will be only until they
shall have become fully inserted. When hard or stony soils are to be
operated upon, the mere tension of the chain L between the drum J and the
point of contact with the ground will not probably render it sufficiently stiff to
drive the spades entirely in, and a plate of metal of proper strength may be
affixed to the machine in such position that the upper side of the chains at
this place shall side upon it, thus preventing the chain from yielding. The
chain itself, however, can be so constructed as to turn or yield only in one
direction, viz., in that of passing over the drums. This construction may be
as follows:- Fig. 2 is a side view or elevation of a portion of the chain;
Fig. 3, a plan view; and Fig. 4, an end view. In these it will be seen that
the spades or forks (m) are affixed upon plates (n), which are turned up at
the ends to form hooks (o), and these plates are connected into a chain by
simple links (r) passing around the hooks. The ends of those hooks are
continued over the surface of the links, as shown in Fig. 3, and it is those
continuations in combination with the bearing of the back of the link at its
end upon the face of the plates which prevents the chain from yielding to
pressure applied against that side from which the forks project. The back of

page_text: bearing.
I claim the combination of a series of forks or spade blades with an endless
chain, and with a drum and pullies, arranged in such order upon a carriage,
that by the progressive onward motion of the machine the said spades or forks
will at first be forced by a direct or nearly direct thrust into the ground, and
'afterward, in the act of being lifted by the chain out of the ground, shall. be
made to turn at such short angle with the surface as will cause the breaking
and upheaval of the ground, substantially as described.
In witness whereof, I, the said Omrod Coffeen Evans, have hereunto'
set my hand and affixed my seal, at the City of New York, this
Second day of May, A.D. One thousand eight hundred and fifty-six. *
ORMROD COFFEEN EVANS. (L.S.)
Taken and declared at Her Britannick Majesty's
Consulate in the City of New York, this 2nd
day of May, A.D. 1856, before me,
ANTH. BARCLAY,
Her Britannick Majesty's Consul for
the State of New York.
Consul's
Seal.