IMPROVEMENTS IN THE CONSTRUCTION OF POTATO DIGGERS
Year: 1876

page_text: LETTERS PATENT to Lewis Augustus Aspinwall, of Albany, in the State of
New York, United States of America, but at present of 33, Chancery Lane, in
the County of Middlesex, for the Invention of "IMPROVEMENTS IN THE
CONSTRUCTION OF POTATO DIGGERS."
Sealed the 4th May 1877, and dated the 6th November 1876.
PROVISIONAL SPECIFICATION left by the said Lewis Augustus Aspinwall
at the Office of the Commissioners of Patents on the 6th November 1876.
LEWIS AUGUSTUS ASPINWALL, of Albany, in the State of New York, United
States of America, but at present of 33, Chancery Lane, in the County of Middlesex.
"IMPROVEMENTS IN THE CONSTRUCTION OF POTATO DIGGERS."
These improvements have chiefly reference to potato digging machines having a
spade in front and a revolving separator appliance behind.
According to this Invention 1 employ a quickly revolving separator having, say,
two blades or paddles forming together a skeleton frame. The two blades unite
and converge at the outside end and terminate at the other or inside end in a ring;
the outer end is fixed to a spindle passing through a long bearing boss forming part
of the side frame. The paddle separator is caused to revolve by suitable gearing
from the road wheel on the same side. The separator is by preference largest in
the centre, in order the better to open the top of the ridge.
In order to separate the earth and retain the potatoes in place, fingers, pegs, or
ribs may be fitted to the inside of the blades, which also may be solid or perforated
or slotted.
The two fingers next to the end ring are by preference slightly curved in order to
turn the tops away from the sides.
I prefer two blades only, but three may be used; for heavy or wet soil I find
two blades are suitable. The ploughshare is also supported from the same side as
the separator, and may be fitted with loose or hinged fingers' in order to prevent
stones from catching in between the plough and the separator.

page_text: 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
5th May 1877.
LEWIS AUGUSTUS ASPINWALL, of Albany, in the State of New York, United
States of America, but at present of 33, Chancery Lane, in the County of Middlesex.
"IMPROVEMENTS IN THE CONSTRUCTION OF POTATO DIGGERS.".
These improvements have chiefly reference to potato digging machines having a
spade in front and a revolving separator appliance behind.
According to this Invention I employ a quickly revolving separator having, say,
two blades or paddles forming together a skeleton frame. The two blades unite
and converge at the outside end and terminate at the other or inside end in a ring;
the outer end is fixed to a spindle passing through a long bearing boss forming part
of the side frame. The paddle separator is caused to revolve by suitable gearing
from the road wheel on the same side. The separator is by preference largest in
the centre in order the better to open the top of the ridge.
In order to separate the earth and retain the potatoes in place, fingers, pegs, or
ribs may be fitted to the inside of the blades, which also may be solid or perforated
or slotted.
The two fingers next to the end ring are by preference slightly curved in order to
turn the tops away from the sides.
I prefer two blades only, but three may be used; for heavy or wet soil I find
two blades are suitable. The ploughshare is also supported from the same side as
the separator, and may be fitted with loose or hinged fingers in order to prevent
stones from catching in between the plough and the separator.
Figure 1 of the accompanying Drawings is a side elevation; Figure 2, a longi-
tudinal section; and Figure 3, a plan of a potato digging machine constructed
according to this Invention.
The side frame A is supported by a long sleeve upon the main shaft B, whereon
the road wheels c and c revolve. loosely. The spade D is fixed to the adjustable
supporting bar E, the height of the spade being regulated by a set screw F. When
however it is desired to lift the spade quite clear of the ground, as is necessary
when the machine is being traversed from place to place, the handle or lever G is
drawn from a vertical into a horizontal position, thereby raising the part centred
at a, and thus elevating the bracket H, frame A, bar E, and spade D. The knee
of the cranked portion of the lever G is provided with a friction roller b to render
this raising operation more easy. Immediately behind the spade the separator I is
situated; it is composed, as seen more particularly at Figure 4, of two blades or
paddles c springing at the outer end of the separator from a central shaft d, and
held in position at the other end by the ring e. The blades are preferably curved,
as shewn, and the greatest diameter of the separator is at its central part, that is to
say, that part acting immediately over or upon the top of the ridge containing the
potatoes.
To ensure a more perfect disintegration between the earth and the tubers, pegs,
bars, or fingers f are fastened between the blades. It may also be here remarked
that although the blades c may be set parallel with the central shaft d, I prefer to
set them at an angle therewith or somewhat spirally, so as to cause the potatoes to
be thrown to one side as they are passed through the apparatus.
The separator is caused to revolve at the desired speed by suitable gearing
actuated from one or both, but preferably both of the road or carrying wheels c
and c¹. As has been said the carrying wheels revolve loosely upon the shaft B;
nevertheless the said shaft can be caused to partake of the forward motion of the
carrying wheels by placing the ratchet pawls J into gear with the teeth of
ratchet wheels K, which being fixed to the shaft B impart motion thereto. A spur
wheel L is also fixed upon the shaft B, and gears with a pinion M on the central
shaft d of the separator, so that when the shaft B revolves the separator I is

page_text: similarly actuated, but in a direction opposite to that of the carrying wheels. The
shaft d of the separator is carried in a bracket bearing g. The potato top divider N
runs in the furrow and is supported by a carrying wheel. A fence o is likewise
employed to elevate the potato tops, and assist the action of the spade.
As will be observed from the Drawings the driver's seat is placed well to the rear
of the machine, so as to assist in counterbalancing the down drag in front caused by
the lifting action of the spade. The draught power is attached in the ordinary
manner to the pole P. The oil holes whereby the shaft B is lubricated are covered
by flexible covers h made of india-rubber or other suitable material.
When a cover constructed as shewn is placed over the oil hole, dust and dirt are
completely excluded, nor can the cover be jolted out of position.
Figure 5 is a "diagrammatic" view of a simplified arrangement for raising and
lowering the spade. The carrying bar E is here shaped like the segment of a circle
and is prolonged into a handle or lever for operating the same. Ratchet teeth are
also formed on one side of the said segmental supporting bar E, and a pawl is
provided to take into these teeth and support the spade at the desired height.
And having thus fully described and ascertained the nature of this my Invention,
I declare that I claim,-
Firstly. The employment in potato digging machines of a flat separator, con-
structed and operating substantially as set forth.
Secondly. Supporting the said separator at one side as set forth.
Thirdly. Fitting the said separator with cross bars or fingers, as set forth.
Fourthly. The said separator arranged and combined with the spade and other
working parts of a potato digging machine, as here set forth.
In witness whereof, I, the said Lewis Augustus Aspinwall, have hereunto set
my hand and seal, this Third day of May, in the year of our Lord One
thousand eight hundred and seventy-seven.
L. AUG. ASPIN WALL. (L.S.)