IMPROVEMENTS IN THE CONSTRUCTION OF POTATOE DIGGERS
Year: 1875

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
PROVISIONAL SPECIFICATION left by the said Lewis Augustus
Aspinwall at the Office of the Commissioners of Patents, with his
Petition, on the 2nd December 1875.
I, 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, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF POTATOE DIGGERS," to
be as follows:—
This Invention, which constitutes an improvement upon the potatoe
digger for which Letters Patent were granted to me the 23rd October,
A.D. 1874, No. 3655, relates more especially to a novel arrangement and

page_text: construction of the separators described and claimed in the said Speci-
fication of Letters Patent.
According to my improvements a single compound separator is
employed, and situated immediately under the main axle of the
machine, from which also it is driven. It consists of a series of ring
discs measuring in diameter towards the central disc of the series,
arranged at equal distances apart, and waved or corrugated at their
outer peripheries. These discs are held in their place and at the proper
distance from each other by means of separating pieces, through which
and also through the discs a bolt passes, and is secured to the end discs
or plates, the whole series of disc rings being thereby bound firmly
together. Within this outer separator an inner and smaller separator
is arranged, composed of any suitable number of discs, having their
edges or peripheries corrugated similarly to those of the outer and larger
separator. These inner discs are fixed upon a central spindle, and driven
by a wheel and pinion or other suitable gearing in the same direction as
the outer separator, but at a higher, say twice, the speed. The sepa-
rating pieces or stays whereby the discs of the outer separator are held
apart have formed on them or are provided with teeth or projections,
which enter between the discs of the inner separator and prevent the
same from being clogged or choked while in operation, at the same time
that they assist in the disintegration of the tubers from the soil.
By means of this arrangement of compound separator a gradual sepa-
ration is effected, the machine works more steadily, and the destructive
effects of bringing the potatoes whilst almost in a state of rest into
sudden contact with a rapidly revolving disintegrator is avoided, for by
the means just described they are met first by the outer and more slowly
revolving separator, whereby they are partly rid of the soil, an entire
separation being afterwards effected by the inner and more rapidly
revolving discs.
The arrangement of potato digging machine to which this separator
is applied being substantially the same as that already particularly
described and ascertained by me in the Specification of Letters Patent
herein-before referred to, I have considered it unnecessary to incorporate
the same herewith, the present Specification relating substantially to the
improved separator herein described.

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 2nd June 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, 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, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Second day of December, in the year
of our Lord One thousand eight hundred and seventy-five, in the
thirty-ninth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Lewis Augustus Aspinwall,
Her special licence that I, the said Lewis Augustus Aspinwall, my
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 law-
fully 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 POTATOE 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 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.
3.
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 ascer-
tained in and by the following statement, reference being had to the
accompanying Drawings, and to the letters of reference marked thereon,
that is to say :-
This Invention, which constitutes an improvement upon the potato
digger for which Letters Patent were granted to me 23rd October,
A.D. 1874, No: 3655, relates more especially to a novel arrangement

page_text: and construction of the separator described and claimed in the said
Specification of Letters Patent.
According to my improvements a single compound separator is
employed, and situated immediately under the main axle of the
machine, from which also it is driven. It consists of a series of ring
discs (increasing in diameter towards the central disc of the series)
arranged at equal distances apart, and waved or corrugated at their
outer peripheries. These discs are held in their place and at the proper
distance from each other by means of separating pieces, through which
and also through the discs a bolt passes, and is secured to the end discs
or plates, the whole series of disc rings being thereby bound firmly
together. Within this outer separator and inner and smaller separator
is arranged, composed of any suitable number of discs, having their
edges or peripheries corrugated similarly to those of the outer and larger
separator. These inner discs are fixed upon a central spindle, and driven
by a wheel and pinion or other suitable gearing in the same direction as
the outer separator, but at a sensibly higher speed. The separating
pieces or stays whereby the discs of the outer separator are held apart
have formed on them or are provided with teeth or projections, which
enter between the discs of the inner separator and prevent the same
from being clogged or choked while in operation, at the same time that
they assist in the disintegration of the tubers from the soil.
And in order that this my Invention may be more fully understood I
will now describe the same with reference to the accompanying Sheet of
Drawings.
Figure 1 is a side elevation of a machine constructed according to this
Invention; Figure 2 is a vertical section of the same; Figure 3 is a plan
with the driver's seat removed; while Figures 4 and 5 are detail views
of the compound separator.
The side frames A of the machine are held together by cross stays B,
and mounted on the bearing wheels C by means of the axle D. Horses
or other draught power may be attached to the pole E. When drawn by
animals the driver is provided with a seat, as shewn. Coulters F are
arranged one at each side of the digger, having their outer ends sup-
ported by a concave roller G, which runs upon the top of the ridge, the
height whereof is indicated by the dotted line marked a, Figures 1
and 2. The coulters can be adjusted as to the depth of penetration into

page_text: the soil by shifting the bolt finto different holes in the side frames. The
duty of these coulters is to gather the vines or tops. The soil is dug or
lifted by the flat blade or spade H, fixed to the framing in the inclined
position shewn on the Drawings. The mingled soil and potatoes lifted
by the blade H are next brought against and passed through the com-
pound separator, situated in rear of the blade, and shewn more distinctly
at Figure 4. The outer portion of the said separator consists of any
suitable number of flat ring discs I, having their outer peripheries
waved or corrugated as shewn, held at equal distances apart by sepa-
rating pieces J, and secured firmly together by bolts K to the ends L, as
will be seen by referring to Figures 3 and 4; and these discs I increase
in diameter as they approach the central part of the separator, and I
prefer that they should thus increase.
Figure 5 is a vertical section of a separator in which the outer flat
ring discs I are held together by means of three bolts K instead of two,
as shewn at Figure 2. The ends L are formed with hollow trunnions,
which run in journals in the frames A, the said journals being protected
from earth and dust by projecting lips or eaves formed upon the ends L:
This outer part of the separator receives motion from a spur wheel driven
by one of the bearings wheels C, and gearing with the pinion M, which is
fixed on one of the hollow trunnions. The inner part of the separator
consists of a series of flat discs O fixed upon a central spindle N, their
edges or peripheries being waved or corrugated similarly to the ring
discs I. It is preferred that the number of these discs O shall be double
that of the ring discs I, and also that they should be arranged in the
manner shewn at Figures 3 and 4, that is to say, every other inner flat
disc O covered by an outer ring disc I, and all of them equidistant.
:
To prevent the inner part of the separator from becoming clogged
fingers are formed upon the separating pieces J, which project between
the discs O and remove any obstruction that may gather there.
The spindle N is supported in the hollow trunnions in the ends L, and
is driven from the pinion P, which gears with a spur wheel actuated by
one of the bearing wheels C.
It will be seen that the pinion P is considerably less in diameter than
the pinion M, and thus the spindle N and discs O are in this case driven
at a much higher speed than the outer ring disc I (the direction of
revolution being contrary to that of the bearing wheels C). The con-

page_text: Sixth. The general arrangement, construction, and combination of
mechanism, constituting the improved potato digger, all substantially as
herein-before described and shown.
In witness whereof, I, the said Lewis Augustus Aspinwall, have
hereunto set my hand and seal, this Thirtieth day of May, in
the year of our Lord One thousand eight hundred and seventy-
six.
L. AUG. ASPINWALL. (L.S.)