IMPROVEMENTS IN DIGGING MACHINERY
Year: 1863

page_text: LETTERS PATENT to Ormrod Coffeen Evans, Doctor of Medicine,
Citizen of the United States of America, but now resident in Man-
chester, County of Lancaster, for the Invention of "IMPROVEMENTS IN
DIGGING MACHINERY."
Sealed the 18th March 1864, and dated the 29th October 1863.
PROVISIONAL SPECIFICATION left by the said Ormrod Coffeen Evans at
the Office of the Commissioners of Patents, with his Petition, on the
29th October 1863.
I, Ormrod CoffeEN EVANS, Citizen of the United States of America, but
now resident in Manchester, County of Lancaster, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN DIGGING MACHINERY,"
to be as follows:-
The improvements consist in altering the construction of parts of the
machine for which Letters Patent were granted to me, dated 17th December
1855, and numbered 2848, and in adding thereto certain new devices whereby
its adaptation is secured to purposes not formerly contemplated. The liability
to breakage while working is provided against, and parts of the machine
admit of being adjusted at will preparatory to and while working, provisions
positively essential, but not hitherto made. The machine is also rendered
much more portable, and admits of being handled with greater facility; its
weight,proportional to the amount of work done, is also greatly lessened, and
its more perfect action upon the soil secured.
My former machine consisted of a framework mounted upon two truck
Price 811

page_text: wheels, in which framework revolved side by side in parallel planes a series
of drums or broad-faced wheels, over which and also over two rollers placed
at different levels, the one before and the other behind the drum wheels,
and resting upon the ground, passed a series of endless chains carrying teeth
or digging forks, which as the machine was drawn forward were pressed into
the ground, and made to break and turn up the soil.
My improved machine for the purpose of more conveniently raising and
lowering the digging machinery at will, and removing it safely from place to
place, is provided with two separate frames, the inner of which carries the
drum wheels, rollers, and endless chains, and is attached to the outer frame
which carries the truck wheels by means of four loose pins or bolts, two at
the posterior extremities of the side plates and also two at the anterior
extremities, which latter attachments form fulcrums about which the inner
frame turns when raised or lowered to clear the teeth from the ground, or
bring them into the working position. In addition to the two side truck
wheels which are mounted upon the outer or carrying frame, a third wheel,
similar in construction to a castor, is placed under the fore part of the
carrying frame, and as far back as the working position of the teeth will
allow, to enable the machine to turn in small space, and at the same time to
afford support to that part of the carrying frame. For raising of the inside
frame before turning round, and subsequently lowering it, a half-spur wheel
is placed on each side of the machine, behind the digging machinery, and made
to turn upon short arm-shafts projecting from the side pieces of the carrying
frame. Each of these half-spur wheels is provided with a strong radial arm,
into each of which a pin is affixed; on each of these pins work one end of a
connecting bar, and the other ends are attached in a similar way to the two
pins already referred to at the posterior extremities of the side plates of the
inner frame. Pinions gearing into the spur wheels are affixed to a shaft
which extends across the outside frame, and rests upon it, and upon either
end of this shaft is affixed a winch, by turning which the one way or the
other the half-spur wheels are turned round and the inner frame with the
digging machinery is raised or lowered, and it is kept in any desired position
by a bolt which slides upon the outer frame being pressed between the teeth
of the pinion at that side.
When it may be more convenient for the driver to ride, a seat is provided
on the top of the carrying frame in front of and beyond the reach of the
teeth, and by means of an endless chain working over a cog wheel on the
pinion shaft, and passing forward over a similar but smaller cog wheel, which
is mounted upon a support attached to the same frame, and provided with a

page_text: winch upon its axle, the driver is enabled to raise and lower the digging
machinery without leaving his seat.
For the purpose of further raising the machinery when about to be drawn
from field to field, and for regulating the angle which the chain makes with
the surface at that part where the digging teeth enter the ground, the front
part of the carrying frame is raised and lowered by means of an upright screw
working through a beam above the carrying frame, and down into a nut that
is firmly fixed in the end piece of the same frame.
This beam rests upon
upright posts which rise from the sand board or rocker above the castor
wheel, and which, being before and behind the front part of the carrying
frame, prevent it from shifting backwards, forwards, or laterally. To afford
additional strength, two stays, one at each side of the machine, are attached to
the sand board or rocker above the front wheel, and also attached to theshaft
of the side truck wheels.
To admit of a sufficient lateral motion in the digging teeth to enable them
to clear any obstruction while working, and at the same time prevent the
chains from departing from their proper positions upon the drum wheels and
rollers, the latter are provided with V grooves, and the plates to which the
teeth or forks are attached have corresponding projections which fit into
these grooves as the chains travel round them.
Instead of having only two rollers in my machine, as formerly, I introduce
a third roller above the back roller which is upon the ground and behind
it, by which means the chains leave the ground, making an acute angle
with the surface, and the teeth after leaving the ground are still pointing
downwards, thus admitting of grass or any other substance falling off, and
preventing it from being carried round the drums & rollers. The axles of the
rollers revolve in boxes which are inserted in longitudinal openings, and admit
of sliding to a certain extent backwards or forwards. In front of each box
of the lowest roller behind the machine is affixed a spiral spring of sufficient
stiffness to keep the chains distended in the ordinary operation of breaking up
the soil, but capable of yielding to a greater pressure, and preventing the
chain from breaking on any substance getting between the chains and rollers,
or on the teeth coming in contact with firmly-imbedded stones while leaving
the ground.
For the purpose of reducing the resistance offered to the teeth on entering
the ground to about one-half, and diminishing the weight of the machine in
like proportion, the teeth are formed out of sheet steel ranging in guage from
10 to 20, and curved in the blade into about a semicircular form. The upper
part of the tooth which forms the shank is cut a little wider than the rest,

page_text: and bent into a circular form, but of less diameter than the under part. The
shank of the tooth is inserted into a socket of the link suitably prepared for
it, and secured therein by a plug driven into the shank.
To adapt the machine to purposes not formerly contemplated in its con-
struction, viz., the top dressing of pastures and meadows with soil taken from
underneath the sod by the simple action of the machine, it is only necessary
to provide a separate set of teeth which may be inserted into the same links
in place of the other teeth, or an extra set of hook links and teeth may be
provided according to convenience. The teeth for this purpose differ from
those already described only inasmuch as the middle part of the tooth below
the shank is compressed and flattened so as to project forward, and form a
fleam-like cutter which divides the sod, so that the lower part of the tooth can
easily carry up the soil from underneath, and from the velocity with which it
leaves the ground scatter it over the surface,
Although the machine constructed as above may be used for top dressing,
yet as for this purpose a great weight is not required, a single frame will be
found sufficient, in which case the castor wheel is placed under the front part
of this frame, as before described, and for like purposes, and the side carrying
wheels, instead of being attached to the frame as before, are connected with
the extremities of levers of, the second order, so that their axles form the
fulcrums of these levers, andata suitable distance from their extremities; the
shaft of the drum wheels also pass into these, being made to project beyond
the frame on each side for that purpose. By raising the longer ends of these
levers towards the vertical position, the frame with the machinery is raised
from off the ground at the back end, and for retaining the machinery at
any desired elevation, a ratch of a quad rant form is fixed to the upper side of
the frame, and the levers carry an appropriate catch. In machines con-
structed in this manner and used for this purpose, the front roller may be
omitted, as the teeth, from their not being of great length, may be made to
penetrate the sod without any such aid.
Instead of the cutting being performed entirely by the flattened portions of
the teeth, as above described, a series of steel disk-cutters may be placed in
front of the drum wheels, and in line with the chains and teeth, and fixed upon
a shaft which runs from side to side of the frame and is furnished with boxes
and adjusting screws for the purpose of raising and lowering the cutters into
any desired position. By this arrangement the sod is severed into strips, and
the rows of teeth following up enter into these incisions, and easily throw up
the earth from beneath.
Instead of one entire roller acted on by springs, as above described, I some-

page_text: times use a separate short roller for each chain fitted up with springs in the
same way, and supported in plates parallel to the side plates of the frame;
which arrangement admits of a roller yielding to one chain, while the rest
remain distended.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Ormrod Coffeen Evans in the Great Seal Patent Office on the
18th April 1861.
1
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ORMROD
COFFEEN EVANS, Doctor of Medicine, Citizen of the United States of
America, but now resident in Manchester, County of Lancaster, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of October, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty-sixth year of
Her reign, did, for Herself, Her heirs and successors, give and grant -unto
me, the said Ormrod Coffeen Evans, Her special licence that I, the said
Ormrod Coffeen Evans, my executors, administrators, and assigns, or such
others as I, the said Ormrod 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 King-
dom of Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "IMPROVEMENTS IN DIGGING MACHINERY," upon the condition
(amongst others) that I, the said Ormrod 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 Ormrod Coffeen Evans, do hereby
declare the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
Theimprovements consist in alteringtheconstruction of parts of the machine
for which Letters Patent were granted to me, dated 17th December, 1855,
and numbered 2848, and in adding thereto certain new devices, whereby its

page_text: adaptation is secured to purposes not formerly contemplated, the liability to
breakage while working is provided against, and parts of the machine admit
of being adjusted atwill preparatoryto andwhileworking,provisions positively
essential, but not hitherto made. The machine is also rendered much more
portable, and admits of being handled with greater facility; its weight,
proportional to the amount of work done, is also greatly lessened, and its
more perfect action upon the soil secured.
My former machine consisted of a framework mounted upon two truck
wheels, in which framework revolved, side by side in parallel planes, a series
of drums or broad-faced wheels, over which, aud also over two rollers placed
at different levels, the one before the drum wheels, and the other behind and
resting upon the ground, passed a series of endless chains carrying teeth or
digging forks, which, as the machine was drawn forward, were pressed into the
ground and made to break and turn up the soil.
One form of my improved machine is represented in Fig. 1 and Fig. 2, the
former being a side view aud the latter a plau or top view of the same con-
structed for one endless chain and set of teeth, which is here omitted.
For the purpose of more conveniently raising and lowering the digging
machinery at will aud removing it safely from place to place, the machine is
provided with two separate frames, the inuer B of which carries the drum
wheels E, rollers and endless chains c, and is attached to the outer frame A,
which carries the truck-wheels C, by means of four loose bolts or pins, two at
the posterior extremities of the side pieces, and also two at the anterior
extremities. These latter points of attachment admit of being raised or
lowered by means of boxes or blocks sliding in vertical groves in a descending
portion of the outer frame, and retained at the desired hight by screws, and
they form fulcrums, about which the inner frame turns when raised or lowered
to clear the teeth from the ground or bring them into the working position.
In addition to the two side truck-wheels, which are mounted upon the outer
or carrying frame, a third wheels f,similar in construction to a castor, is placed
under the fore part of the carrying frame, and as far back as the working
position of the teeth will allow, to enable the machine to turn in small space,
and at the same time to afford support to that part of the carrying frame.
For raising of the inside frame before turning round, and subsequently
lowering it, a half or smaller portion of a spur-wheel (9) is placed upon each
side of the machine behind the digging machinery, and made to turn upon
short-arm shafts h, projecting from the side pieces of the carrying frame.
Each of these half-spur wheels is provided with a strong radial arm i, into
each of which a pin bis affixed. On each of these pins works one end of a

page_text: connecting bar j, and the other ends are attached in a similar way to the two
pins a already referred to at the posterior extremities of the side pieces of the
inner frame. Pinions k gearing into the spur wheels are affixed to a shaft e,
which extends across the outside frame and rests upon it; and upon either
end of this shaft is affixed a winch, by the turning of which the one way or the
other the half-spur wheels are turned round, and the inner frame with the
digging machinery is raised or lowered; and it is kept in any desired position
by a bolt, which slides upon the outer frame, being pressed between the teeth
of the pinion at that side.
When it may be more convenient for the driver to ride, a seat m is provided
on the top of the carrying frame, in front of and beyond the reach of the
teeth, and by means of an endless chain working over a cog-wheel ŉ on the
pinion shaft and passing forward over a similar but smaller cog wheelo, which
is mounted upon a support p attached to the same frame and provided with a
winch upon its axle, the driver is enabled to raise and lower the digging
machinery without leaving his seat; and the machinery is retained at the
desired height, as in the former case, by a sliding bolt upon the support p,
being allowed to pass between the teeth of the spur-wheel o, which bolt is
acted upon by a helical spring controlled by the foot of the driver:
For the purpose of further raising the machinery when about to be drawn
from field to field, and for regulating the angle which the chain makes with
the surface at that part where the digging teeth enter the ground, the front part
of the outer or carrying frame is raised and lowered by means of an upright
screw r working through a beams above the carrying frame, and down into a
nut that is fixed to the end piece of the same frame. This beam rests upon
upright posts u, which rise from the sand-board or rocker above the castor
wheel, and which, being before and behind the front part of the carrying
frame, prevent it from shifting backwards, forwards, or laterally.
To afford additional strength two stays v, one at each side of the machine,
are attached to the sand-board or rocker above the front wheel, and also
attached to the shafts of the truck wheels. The posts u are made curved, so
that the center of their curvature is at the center of the axis of the truck
wheels, that being the point about which the frame turns. The thills F, by
which the machine is drawn, are attached to the frame of the castor wheel at
a sufficient height to enable the joint to remain in an easy working position
without cramping.
Instead of having only two rollers in my machine, as formerly, I introduce a
third roller D above the back roller and behind it, by which means the chains
leave the ground, making an acute angle with the surface, and the teeth after

page_text: leaving the ground are still pointing downwards, thus admitting of grass or
any other substance falling off, and preventing it from being carried round the
drums and rollers. The axles of the rollers revolve in boxes, which are
inserted in longitudinal openings, and admit of sliding in grooves to a certain
extent backwards and forwards, and are kept in position by screws. In front
of each box y of the lowest roller, behind the machine, is inserted a helical
spring z, of sufficient stiffness to keep the chains distended in the ordinary
operation of breaking up the soil, but capable of yielding to a greter pressure,
and preventing the chains from breaking on any substance getting between
the chains and rollers, or on the teeth coming in contact with firmly imbedded
stones on leaving the ground.
For the purpose of reducing the resistance offered to the teeth on entering
the ground to about one half, and diminishing the weight of the machine in
like proportion, the teeth are formed out of sheet steel, ranging in guage
from 10 to 20, and bent in the blade into a semicircular or angular form.
The upper part of the tooth, which forms the shank, is cut a little wider than
the rest and bent into a circular or triangular form but of less diameter than
the under part.
a
Figs. 6 & 7 are respectively front and top views of teeth of the circular
form and the link or plate to which they are attached, and Figs. 4 & 5
represent the same when the teeth are made of an angular form. The shank
of the tooth is inserted into a socket a of the link or plate suitably provided,
and secured therein by plug driven into the shank to admit of a sufficient
lateral motion in the digging teeth to enable them to clear any obstruction
while working and at the same time prevent the chains from departing from
their proper positious upon the drum wheels and rollers, the latter are provided
with V-shaped grooves, as shown at a in Fig. 2, and the plates or links to
which the teeth are attached have corresponding projections c, Figs. 4 & 6,
which fit into these grooves as the chains travel round them.
To adapt the machine to purposes not formerly contemplated in its con-
struction, viz., the top dressing of pastures and meadows with soil taken from
underneath the sod by the simple action of the machine it is only necessary
to provide a separate set of teeth, which may be inserted into the same links,
in place of the other teeth, or an extra set of hook links and teeth may be
provided, according to convenience. The teeth for this purpose are represented
in Figs. 10 & 11, which are respectively side and front views of the same;
and differ from those already described only inasmuch as the middle part
of the tooth below the shank is compressed and flattened so as to project
forward, and form a fleam-like cutter which divides the sod.so that the lower

page_text: 2
part of the tooth can easily carry up the soil from underneath and scatter it
over the surface. Although the machine constructed as above may be used
for top dressing, yet, as for this purpose a great weight is not required, I
prefer the form of machine of which Fig. 3 is a side view, and in which only
one frame B is used. In this case the castor wheel is placed under the front
part of this frame, as before described and for like purposes, and the side
carrying wheels C, instead of being attached to an outer frame as before, are.
connected with the extremities of levers of the second order, so that their
axles form the fulcrums of these levers, and at o the shafts of the drum wheels
also pass into these. By raising or lowering the longer ends of these levers
towards the vertical position, either by the hand directly or by a winch &
pinion upon a shaft passing across the machine, the machinery is raised or
lowered, and for retaining the machinery at the desired elevation, a ratch of a
quadrant form is fixed to the upper side of the frame and the levers carry an
appropriate catch.
The front roller in these machines may be omitted, as
the teeth, from their being of no great length,may be made to penetrate thesod
without any such aid. Instead of the cutting being performed entirely by the
flattened portion of the tooth as above described, a series of steel disk cutters m
may be placed in front of the drum wheels and in line with the chains and
teeth, and fixed upon a shaft which runs from side to side of the frame and is
furnished with boxes n and adjusting screws p for raising or lowering the
cutters into any desired position. By this arrangement the sod is severed into
strips and the rows of teeth entering these incisions easily throw up the earth
from underneath. Figs. 8 & 9 are top and side views of the cutters m,
showing the shafts and cylindrical thimbles t, by which the cutters are fixed
upon the same.
Having now described and ascertained the nature of mysaid Invention, and
the manner in which the same is to be performed, I would remark in con-
clusion that I do not limit myself to the precise details herein expressed and
shewn, as the same may be modified in various ways without departing from
the principles upon which my Invention is based, but what I claim under the
in part recited Letters Patent are the various combinations and appliances
used in the manner and for the purpose herein-before described, viz:-The
castor wheel, the various contrivances for raising and lowering the frames &
digging machinery and for retaining them at the desired elevation, the various
forms of teeth and the methods of attaching them to the links, the arrange-
ments for keeping the chains in their proper positions upon the drums and
rollers, the third roller D, the sliding boxes and the helical springs in front of

page_text: the shafts of the lowest roller, the disk cutters and the general construction of
the machines shewn in Figs. 1, 2, & 3.
. In witness whereof, I, the said Ormrod Coffeen Evans, have hereunto set
my hand and seal, this Sixteenth day of April, in the year of our Lord
One thousand eight hundred and sixty-four.
ORMROD COFFEEN EVANS. (L.S.)