IMPROVEMENTS IN DIGGING MACHINERY
Year: 1867

page_text: LETTERS PATENT: to Ormrod Coffeen Evans, West Dulwich, in the
County of Surrey, for the Invention of "IMPROVEMENTS IN DIGGING
MACHINERY."
Sealed the 15th April 1868, and dated the 31st October 1867.
PROVISIONAL SPECIFICATION left by the said Ormrod Coffeen Evans
1 at the Office of the Commissioners of Patents, with his Petition, on the
31st October 1867.
1 I, ORMROD COFFEEN EVANS, of West Dulwich, in the County of Surrey, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN- DIGGING
MACHINERY," to be as follows:-
This Invention relates to improvements in digging machinery of the character.
described in the Specification of a Patent granted to me, and dated the 22nd
day of April 1865, No. 1124, and consists, first, in an improved method, of
arranging one or a series of endless chains' carried by a suitable framework,
so that they can be caused to revolve or roll over the surface of the ground.
The chains have teeth. or digging forks attached to them, and the chains are.
so arranged that they will form an angle or inclined plane as they approach the
surface of the ground, but will rise from the ground at a much more upright
angle, the effect of which arrangement will be to cause the teeth blades or

page_text: digging forks attached to the chain to enter the ground in nearly a vertical
position, and to turn at such a short angle as will suddenly lift the teeth or
digging implements backward, upward, and out of the ground with force
enough to upheave the soil; to this end the chains are each made to encircle
a drum wheel and two rollers. The drum wheel is raised above the ground
line far enough to allow the teeth to enter the ground at right angles with the
chain, and the rollers are placed one behind the other on the ground line
and in such positions behind the drum wheel as to cause the chain to form
an inclined plane from the under side of the drum wheel to the under side of
the front roller, and also so to pass around the hind roller as will cause the
teeth to be lifted suddenly out of the ground from a vertical to a horizontal
position. For the sake of convenience I will herein-after term the front
roller the inserting roller, and the hind roller the lifting roller. The drum
wheels revolve side by side upon the same shaft, the inserting rollers in like
manner on a single shaft, and the lifting rollers in the same parallel planes,
but each on a separate shaft. The drum wheels are in diameter about twice
the length of the teeth, the inserting rollers about three-fourths the diameter
of the drum wheels, and the diameter of the lifting rollers half the length of
the teeth, more or less. Each'inserting roller is' formed by placing side by
side two flanged discs with flanges facing each other and placed far enough
apart to allow each disc to lap over the side of the drum wheel or the drum
wheel to pass in between them. The lifting rollers revolve as before stated
each on a separate shaft, which has its support in the ends of longitudinal
arms that extend from the drum wheel shaft backwards, one support on each
side of the drum wheel, and between the drum wheel and dises to the disc or
inserting roller shaft, and from this shaft (which together with the drum wheel
.shaft is their support) just far enough back to allow the lifting"roller to revolve
between the discs, and at the same time render vertical so much of the chain
as extends from the back of the lifting to the back of the inserting roller.
A slot is formed in each arm through which the:drum wheel shaft passes for
the purpose of allowing this shaft to move back or forward in adjusting the
position of the drum wheels to the rollers preparatory to attaching, hooking,
or unhooking the chains. The drum wheel and inserting roller shafts have
their support in side pieces of an inner frame which are attached. to an outer
frame that is mounted upon truck wheels; the attachment is made at any
suitable point on or behind the vertical centre of the drum wheels, and is so
attached as to form an axis around which the inner frame partially revolves,
and pinions fixed on a shaft that has its support on the outer frame take into
the teeth of a rack formed on the hinder ends of each side piece of the inner

page_text: frame, which can be raised and lowered by this means. A suitable locking
instrument attached to the outer frame is provided to hold the digging and
outer frame in any desired relative position to each other. Suitable boxes
or bearings are provided for the drum wheel shaft to. revolve in, and these;
bearings are inserted in slotted openings parallel with the inclined plane of
the chains in such manner as will admit of their being moved either back or,
forward, the position of such roller being regulated by means of adjusting.
screws or otherwise, for the purpose of hooking or unhooking or, adjusting
the chains to any desired tension. Curved slotted openings are provided in
the outer frame for the bearings to the pins which form the fulcra around
which the inner frame turns, and which are raised and lowered by means of
adjusting screws or otherwise, and by these means the amount of inclination,
of the chains can be increased or lowered or the internal frame raised
when the machine is moved ou common roads or from field to field., The
teeth are made or formed from square steel and set angularly to their work
by being inserted into corresponding sockets in the links, in which they are
secured by means of set screws.
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 30th April 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ORMROD
Coffeen Evans, of West Dulwich, in the County of Surrey,, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters.
Patent, bearing date the Thirty-first day of October, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirty-first 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 Orinrod 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
mike, use, exercise, and vend, within the United Kingdom 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 scals,

page_text: 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 the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement thereof, that is to say :-
This Invention relates to improvements in digging machinery of the
character described in the Specification of a Patent granted to me, and dated
the 22nd of April 1865, No. 1124, and consists, first, in an improved method
of arranging one or a series of endless chains carried by a suitable framework
so that they can be caused to revolve or roll over the surface of the ground,
These chains have teeth or digging forks attached to them as well as being
so arranged on drum wheels and rollers that they will form an angle or
inclined plane as they approach the ground, but will rise from the ground at a
much more abrupt angle, the effect of which arrangement will be to cause the
teeth or digging forks attached to the chains to enter the ground in nearly a
vertical position and again to turn at so short an angle as will suddenly lift
the teeth or digging forks backward, upward, and out of the ground with
force enough to upheave the soil.
.
The accompanying Drawing (Figure 1) shows in side elevation an implement
constructed according to my Invention; Figure 2, a plan of the same; Figure 3
a longitudinal vertical section of the digging part of the implement; and
Figure 4 shows the construction of the chains, the form of the teeth, and
method of securing them in the links. Each letter in the different Figures
represents the same or corresponding parts.
A is a frame mounted upon side wheels a, and under the front end is
a single wheel b' attached in such manner to the frame as will allow it
to turn in turning the implement by the pole or "thills" attached to the
framework supporting it; B is an inner frame connected both before and
behind as herein-after described to the outside frame, and which inner frame
supports the digging part of the implement; c, c, are chains which are
arranged so as to encircle the drum wheels C and the rollers D and E.
The drum wheels are raised above the ground line far enough to allow the
teeth at d to commence entering the ground and the chains from d to e form
an inclined plane, by which means the teeth are gradually thrust in the
ground by the weight and forward motion of the implement. From e to f
the chains are on the ground line, or horizontal, and from which the teeth

page_text: at are suddenly lifted from their vertical to a horizontal position, as
at g, an action as the chains turn on the rollers E sufficiently rapid to secure
the breaking up of the soil. For the sake of convenience I will herein-
after term the front roller the inserting roller and the hind roller the .lifting
roller. The drum wheels C are supported on the single shaft h, and the
inserting rollers E in like manner on a single shaft i and the lifting rollers E
in the same parallel planes, but each on a separate shaft or axis. Each
inserting roller is formed by placing side by side two flanged discs with
their rims j, j, facing each other and placed far enough apart for their rims
to rest on the ends of the links k of the chains c. The lifting rollers revolve.
as before stated each on a separate shaft or axis which has its support in the
ends 1, 1, of the longitudinal arms F, and which in turn receive their support
by means of the inserting roller and drum wheel shafts passing through
them, one on each side of a drum wheel, and between a disc and lifting
roller extending far enough back to render vertical so much of the chain
at m as extends from the back side of the lifting to the back side of the
inserting rollers. A slot n is formed in each arm F, through which the
drum wheel shaft passes for the purpose of allowing this shaft to be moved
back or forward in adjusting the position of the drum wheels to the inserting
rollers preparatory to attaobing as well as regulating the tension of the.
chains. For this purpose each end of the drum wheel shaft is provided with
a moveable box or bearing o in a slotted opening p in each side piece of
the inner frame B, and is moved back and forward by the adjusting screw q, ;
this slotted opening being parallel with the slots of the longitudinal arms.
and parallel or nearly so with the inclined plane of the chains. The
inserting roller shaft is firmly fixed in the side pieces of the inner frame B,
and which, together with the rod r across the top, holds these side. pieces
in their proper place and completes this inner frame. This inside frame.
is connected with the outside frame at any suitable point on or behind the
vertical centre of the drum wheels by means of a pin inserted through
each side piece of the inner frame, and through sliding boxes a arranged to
slide up and down in a vertical quadrant slotted opening t in the outside
frame and into and through the plate u, and is held in place by a head on
one end and a nut or split pin at the other. The boxes to this pin attachment
are caused to slide up and down by means of adjusting screws v, which are
inserted each through a slot in an ear w on the outside frame, and rests on a
saddle w³, which again rests on the point of a conical bearing w³ on the
upper side of the ear and is made to act below in the ear u¹ of the plate u..
This inner frame is also connected with the outside frame by means of

page_text: pinions fixed on the shaft which has its support on the outer frame, and
which pinions take into the teeth of a quadrant rack formed on the end of each
side piece of the inner frame, and which may be raised and lowered by this
means, and also each frame held in any desired relative position to each
other by the bolts y, which are secured to and slide upon the outer frame
when pressed by the lever into and between the teeth of the pinion at that
side. Thus suspended within the outside frame the pins become the axis
around which this inside frame partially revolves when raised or lowered
by the pinion shaft, and the pinion shaft becomes the axis when the front
end of the inner frame is raised or lowered by means of the adjusting screws
before described. The chains are composed, of plate links k, which hold the
teeth and square or oblong links k, k, which connect these together. On
opposite sides and parallel to each other a portion of cach plate is turned up.
in such manner as to form hooks with lateral projections k³, and when
hooked together by this means. the chains are rigid one way and yielding the
other. The teeth are made of square steel slightly tapered and flattened at
the points, and inserted into sockets raised on the surface of the plates
angularly to their work, and secured in place by set screws k*, k*. On
the under side of each plate link is raised two projections k, k, for the
purpose of holding the chains in place on the drum wheels and rollers while
-working, there being one of such projections on each end about half way
between the centre and the end of the link, and of such height only as will
allow them to clear the ends of the longitudinal arms as the chains pass
around the lifting rollers.
Having thus described the nature of my Invention, and the manner of
carrying the same into practice, what I claim is,-
First. The arrangment of a series of discs mounted upon an axis con-
stituting the inserting roller D revolving in bearings carried by the inner
frame B of the improved arrangement of endless chain digging machinery
berein-before described and shown in the Drawing annexed.
Secondly. I claim the improved method of arranging the lifting roller
or rollers E of endless chain digging machinery by mounting the same upon
arms F carried by the axes h and i the axes of the drum wheels C and
inner frame B being capable of adjustment in relation to the outer frame, as
herein-before described and shown in the Drawing.
Thirdly. I claim the improved form of the teeth, together with their position
and method of securing them to the links of the endless chain, as herein
described and shown in the Drawing.
And, lastly. I claim the improved arrangement and combination of parts

page_text: constituting the endless chain digging machine or implement herein described
and shown in the accompanying Drawing.
In witness whereof, I, the said Ormrod Coffeen Evans, have hereunto
set my hand and seal, this Twenty-seventh day of April, in the year
of our Lord One thousand eight hundred and sixty-eight.
Witness,
J. G. TONGUE,
Patent Agent,
34, Southampton Buildings,
Chancery Lane,
W.C.
O. C. EVANS. (L.S.)