IMPROVEMENTS IN THE CONSTRUCTION OF POTATO DIGGERS
Year: 1874

page_text: LETTERS PATENT to Lewis Augustus Aspinwall, of Albany, in the
Stato of New York, but at present of 89, Chancery Lanc, in the
County of Middlesex, for the Invention of "IMPROVEMENTS IN
Scaled the 16th April 1875, and dated the 23rd October 1874.
PROVISIONAL SPECIFICATION left by the said Lewis Augustus
Aspinwall at the Office of the Commissioners of Patents, with his
Petition, on the 23rd October 1874.
I, LEWIS AUGUSTUS ASPINWALL, of Albany, in the State of New
York, but at present of 89, Chancery Lanc, in the County of Middlesex,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
THE CONSTRUCTION OF POTATO DIGGERS," to be as follows :—
The two travelling or drive wheels run in the furrows on each side of
the ridge. Motion is transmitted from these wheels to two spindles
beneath the wheel axle. I prefer for this purpose to use tooth wheel
and pinion gear, the tooth wheel being fixed to the wheel axle, which is
turned in one direction only by pawl arrangement as now used in mowing.

page_text: machines, but other suitable gear may be substituted so long as both
said spindles turn in the opposite direction to that of the drive wheels,
and that motion is communicated in one direction only, namely, when
the implement is pulled forward. I prefer to enclose the gear in a rim
or case to protect it from earth or dirt.
The two spindles aforesaid are situated one behind the other, and have
their journals or bearings in the side frames of the machine; these
frames I prefer to make of iron instead of wood, as usual heretofore;
- they also carry the bearings for the wheel axle, which bearings are made
with overhanging lip or flange for keeping out dirt or dust. The fore-
most spindle carries a series of eccentric discs; each disc may be formed
as a single eccentric, or it may be made with two or more eccentric
horns. I prefer to arrange the size of these discs in such manner that
they taper off to a smaller size towards tlie side frames so as to form
what might be termed a double conc separator; the other or hindmost
spindle carries a series of circular or polygonal discs, by preference
however circular, with depressions, notches, or corrugations in the
circumference. These discs are so placed as to be between the discs on
the front spindle. Both front and back spindle have cones at the inner
sides of the frames in order to protect the bearings against the entrance
of dirt and to prevent the "vines" from winding. The cones at the
front spindle have fingers sct spirally as regards the centre, and so as to
push the vines towards the centre.
The object of the aforesaid discs on the front and back spindle is to
separate the potatoes from the earth and to carry the vines back, and
leave potatoes and vines on the surface in the rear of the machine. In
advance of the front spindle I fasten an iron plate, or bar, or bracket to
the side frames. This plate carries a flat steel shovel or blade, which is
made somewhat narrower than the distance between the frames. The
object of this blade is to cut through the ridge below the potatoes; it
is furnished with teeth or fingers behind to prevent the potatocs from
falling down before they are taken hold of by the front separating discs.
The blade or shovel is made narrow, as aforesaid, for the purpose of
lessening the friction or resistance to its progress through the ridge.
The pole of the implement is carried by a forked arm jointed to the
side frames, and passes through a bent or cranked portion of the front
cross bar which unites the side frames; the said forked arm carries the

page_text: driver's seat. In the cranked portion of the front cross bar the fulcrum
of a bell-crank lever is arranged, the short arm of which carries a roller
at its end, and the long arm forms a lever handle which is arranged on
one side suitable for the driver. When this lever is operated so as to
press the roller on the short arm against the top of the pole, passing
through at its place and forming an abutment against the force exerted,
the framework of the machine is raised from the ground for facilitating
the turning of the implement or the transport of the same.
From cach of the side frames near the centre of same I attach an arm
projecting out in front of the implement; between these two arms a
double cone roller is supported, which roller is free to revolve; the said
arms also in front carry two coulters or knives which gather the "vines; "
the double cone roller compresses them and guides them towards the
centre of the separators.
In order to prevent the vines from returning to their original position,
and also in order to keep the potatoes from rolling out towards the sides
I place a wing or guard plate on each side of the arms carrying the
double cone roller. The said projecting arms are adjustably fixed to the
side frames, and by shifting their position relatively to the side frames
the latter along with the gear attached thereto can be adjusted to any
required position or depth.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Lewis Augustus Aspinwall in the Great Seal Patent
Office on the 23rd April 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, LEWIS
AUGUSTUS ASPINWALL, of Albany, in the State of New York, but at
present of 89, Chancery Lanc, in the County of Middlesex, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-third day of October, in the
year of our Lord One thousand eight hundred and seventy-four, in
the thirty-eighth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said Lewis Augustus Aspinwall,
Her special licence that I, the said Lewis Augustus Aspinwall, my

page_text: executors, administrators, and assigns, or such others as I, the said
Lewis Augustus Aspinwall, 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 "IMPROVEMENTS IN THE CONSTRUCTION OF POTATO
DIGGERS," upon the condition (amongst others) that I, the said Lewis
Augustus Aspinwall, 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 samo
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 Lewis Augustus Aspinwall, 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, reference being had to the accom-
panying Drawings, and to the letters of reference marked thereon, that
is to say :-
-
This Invention will be best understood by reference to the accom-
panying Drawings.
Figure 1 is a side elevation, Figure 2 is a plan, and Figure 3 a section
of machinery constructed according to my Invention. Similar letters of
reference refer to like parts in all the Figures.
A, A, are the two travelling or driving wheels which run in the
furrows ou cach side of the ridge; motion is transmitted from one or
both of these wheels to two spindles a, a', beneath the wheel axle or
axles b, because in some cases I only use one axle running across the
machine, but in other cases two axles bolted on to the side framing of
the machine, and this arrangement I have shown in the Drawings; c is
tooth wheel loose on its spindle b, but by means of a spring pawl box
arrangement connected to a box on the travelling wheel A so that it
partakes of a revolving motion of the said travelling wheel when the
implement is propelled in the forward direction, but otherwise remains
stationary. The spindles a and a carry pinions 1, 2, which gear into
spur wheel c, and thus when in motion turn in the opposite direction to

page_text: the travelling wheels. I prefer to enclose the gear in a rim or case to
protect it from carth or dirt.
The two spindles a, a', aforesaid are situated one behind the other,
and have their journals or bearings in the side frames D, D, of the
machine; these frames I prefer to make of iron instead of wood as usual
heretofore; they also carry the bearings where one axle is used for the
wheel axle, which bearings are made in such case with overhanging lip
or flange for keeping out dirt or dust. The foremost spindle carrics a
series of eccentric discs d, d; cach disc may be formed as a single
excentric, or it may be made with two or more cccentric horns or fingers,
shewn in the Drawings with two horns. I prefer to arrange the size of
these discs in such manner that they taper off to a smaller size towards
the side frames so as to form what might be termed a double conc
separator, which breaks up the carth. The other or hindermost spindle
carries a series of circular or polygonal discs c, by preference however
circular, with depressions, notches, or corrugations in the circumference,
as shown clearly in the section, Figure 3; these discs are so placed as to
be between the discs don the front spindle a. Both front and back
spindle have cones f, f, at the inner sides of the frames D in order to
protect the bearings against the entrance of dirt, and to prevent the
"vines" from winding; the cones fat the front spindle & have fingers g
set spirally as regards the centre, and so as to push the vines towards
the centre.
The object of the aforesaid discs & and e on the front spindle a and
back spindle a¹ is to break up the carth and to separate the potatoes
from the carth, and to carry the vines back, and leave potatoes and vincs
on the surface in the rear of the machine. In advance of the front
spindle I fasten an iron plate, or bar, or bracket H to the side frames D);
the plate b carries a flat stcel shovel or blade i which is made somewhat
narrower than the distance between the frames; the object of this blade
is to cut through the ridge below the potatoes; it is furnished with teeth
or fingers R, R, as shown at Figure 4, behind to prevent the potatoes
from falling down before they are taken hold of by the front fingers or
discs d. The blade or shovel i is made narrower, as aforesaid, for the
purpose of lessening the friction or resistance to its progress through the
ridge.
The pole E of the implement is carried by a forked arm F jointed to
tuh hand no anonload naution all of 11

page_text: front cross bar G which unites the side frames; the said forked arm F
carrics the driver's seat H. In the cranked portion G¹ of the front cross
bar G the fulcrum of a bell-crank lever is arranged, the short arm m of
which carries a roller n at its end, and the long arm o forms a lever
handle, which is arranged on one side suitable for the driver. When the
lever o is operated so as to press the roller n on the short arm m against
the top of the pole E, passing through at its place and forming an
abutment against the force exerted, the framework of the machine is
raised from the ground for facilitating the turning of the implement or
the transport of the same.
From each of the side frames D near the centre of same I attach an
arm J projecting out in front of the implement; between these two
arms J a double cone roller k is supported, which roller is free to
revolve; the said arms also in front carry two coulters or knives J' which
gather the "vines," the double cone roller k compresses them and guides
them towards the centre of the separator discs & and e.
In order to prevent the vines from returning to their original position,
and also in order to keep the potatoes from rolling out towards the sides,
I place a wing or guard plate L on each side of the arms J carrying the
double cone roller %. The said projecting arms J are adjustably fixed to
the side frames, and by shifting their position relatively to the said
frames the latter along with the gear attached thereto can be adjusted to
any required position or depth.
Having now fully described the nature of this Invention, and the
manner of carrying the same into effect, I declare that I claim,-
First. The employment in such machines of discs e upon the spindle
or shaft a¹, constructed and operating substantially in manner and for
the purposes described and illustrated in the accompanying Drawings.
Second. The employment of eccentric fingers or discs & on the
spindle a, operating and arranged substantially in the manner described
with reference to the accompanying Drawings.
Third. The combination of the separating discs e with the breaking
fingers or discs d, substantially as and for the purposes described and
illustrated in the accompanying Drawings.
Fourth. The employment of a flat narrow blade to cut through middle
of ridge under the potatoes in combination with breaking and separating

page_text: devices, substantially as described and illustrated in the accompanying
Drawings.
Fifth. The making of the frame containing the separating discs wider
at the rear than the fore end, substantially in manner and for the
purposes described.
Sixth. The employment of the wings or guard plates L, L, in com-
bination with the double cone roller k and forked coulters J¹, J¹, all
substantially as described and illustrated in the accompanying Drawings.
Seventh. The combination of the double cone roller k and forked
coulters J', J', with the separating device, substantially as described and
illustrated in the accompanying Drawings.
Eighth. The employment of the bell-crank lever O provided with the
roller n, constructed and operated substantially in the manner and for
the purposes described, and illustrated in the accompanying Drawings.
In witness whereof, I, the said Lewis Augustus Aspinwall, have
hereunto set my hand and seal, this Twenty-second day of April,
in the year of our Lord One thousand cight hundred and seventy-
five.
.