IMPROVEMENTS IN POTATO DIGGERS
Year: 1874

page_text: LETTERS PATENT to John Wallace, of Glasgow, in the County of
Lanark, North Britain, Agricultural Implement Maker, for the In-
vention of "IMPROVEMENTS IN POTATO DIGGERS."
PROVISIONAL SPECIFICATION left by the said John Wallace at the
Office of the Commissioners of Patents, with his Petition, on the
3rd July 1874.
I, JOHN WALLACE, of Glasgow, in the County of Lanark, North
Britain, Agricultural Implement Maker, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN POTATO DIGGERS," to be as
follows:-.
PROVISIONAL SPECIFICATION left by the said John Wallace at the
Office of the Commissioners of Patents, with his Petition, on the
3rd July 1874.
I, JOHN WALLACE, of Glasgow, in the County of Lanark, North
Britain, Agricultural Implement Maker, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN POTATO DIGGERS," to be as
follows:-.
This Invention relates to potato diggers of the kind described in the
Specification of Letters Patent granted to John Hanson and dated 30th
July 1855 (No. 1782).

page_text: In apparatus of the kind referred to a longitudinal shaft driven by
bevil wheels from the axle of a pair of carrying wheels has on its pro-
jecting back end a series of forks, which in revolving pass across the
potato drill and throw out the potatoes against a screen. In digging
potatoes when new, or with an extra or unwithered growth of shaws, it
is found that the revolving forks are apt to become choked by carrying
round the shaws. One of the present improvements has for its object to
prevent this choking, and consists in fixing a disc or annular plate over
the shanks of the digging forks, so that the shaws cannot get into the
narrowing parts between the shanks.
Another improvement relates to the manner of holding the shank of
the sock or shovel, which is forced along through the drill under the
potatoes in advance of the revolving forks. This sock requires to be
very securely held by the frame, but is inconveniently in the way when
running the machine without working, and the improvement consists in
forming the frame socket for holding the shank of the sock with angular
sides, admitting of the shank being turned about a centro pin from one
to another of two positions. In those positions the shank bears against
different faces of the angular socket, but so as to bo solidly supported
in cach. A catch, lever, wedge, or bolt, is used for fixing the sock
shank in either of its positions.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Wallace in the Great Seal Patent Office on
the 1st January 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN 2
WALLACE, of Glasgow, in tho County of Lanark, North Britain, Agri-
cultural Implement Maker, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing dato the Third day of July, in the year of our
Lord One thousand eight hundred and seventy-four, in the thirty-eighth 3
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said John Wallace, Ler special licence that I, the
said John Wallace, my executors, administrators, and assigns, or such
others as I, the said John Wallace, my executors, administrators, and

page_text: assigns, should at any time agree with, and no others, from time to
time and at all times thercafter 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,
5 and Isle of Man, an Invention for "IMPROVEMENTS IN POTATO DIGGERS,"
upon the condition (amongst others) that I, the said John Wallace, 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 John Wallace, 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 in writing, reference being had to the accompanying
Drawings, that is to say :—
My said Invention relates to potato diggers of the kind described in
the Specification of Letters Patent granted to John Hanson and dated
30th July 1855 (No. 1782).
In apparatus of the kind referred to a longitudinal shaft driven by
bevil wheels from the axle of a pair of carrying wheels has on its pro-
jecting back end a series of forks, which in revolving pass across the
potato drill and throw out the potatoes against a screen. In digging
potatoes when new, of with an extra or unwithered growth of shaws, it
is found that the revolving forks are apt to become choked by carrying
round the shaws. And one part of my present Invention has for its
object to prevent this choking.
A second improvement relates to the manner of holding the shank of
the sock or shovel, which is forced along through the drill under the
potatoes in advance of the revolving forks for the purpose of loosening and
slightly lifting the potatoes, so as to facilitate the action of the forks.
i
And in order that my said Invention, and the manner of performing
the same, may be properly understood, I hereunto append a Sheet of
explanatory Drawings, to be herein-after referred to, and representing
the parts of the potato digger to which.my improvements are applied..

page_text: In these Drawings the same reference numerals are used to mark tho
same or like parts wherever they are repeated.
Figure 1 of the Drawings is a sectional side elevation; and Figure 2
is a back elevation, with a portion of the fork wheel supposed to be
broken away. The longitudinal shaft 1 of the machine has fixed on it t
a centre 2, upon which the radiating forks 3 are bolted.
-
My first improvement consists in fixing on the fork wheel a disc or
annular plate 4, so as to partly fill up the angular spaces between the
forks 3, and thereby prevent the shaws from gathering in such angular
spaces and choking or impeding the action of the wheel. To prevent
the shaws from gathering on the shank 5 of the sock or shovel 6 I place
in front of such shank a sharp-edged disc of 12 or 14 inches diameter,
which being held on a transverse horizontal stud on an adjustable bracket
rolls down and cuts the shaws.
My second improvement, which relates to the manner of holding the i
shank 5 of the sock or shovel 6, consists in forming the socket or holding
block 7 attached to or formed on the frame of the machine with angular
sides 8, 8, 9, 9, admitting of the shank 5 being turned about a centro
pin 10 from one to another of two positions. In the drawings the shank 5
is shown in the working position, in which it requires to be held very a
securely and stiffly, and in this position it bears against two diagonally
opposite faces 8, 8, of the holder 7. The other position of the shank is
partly shown in dotted lines 11. The shank 5 is moved into and. held in
either of its two positions by a hand lever 12 centred on the pin 10 out-
side of a cover plate 13 which is bolted to the holder to keep the shank a
in its socket. The lower end of the hand lever 12 is forked to embrace
the shank 5, and the lever is fitted with a sliding catch bar 14, which is
thrust into one or other of two notches formed for it in the holder 7.
Tho-shank-5 of the sock or shovel is made with two or three holes for
the centre pin 10, so that it can be set to suit potato drills of different a
heights. With these improved holding arrangements the sock 6 is held
rigidly and securely whilst working, whilst if the machine is running
without working the sock can be shifted easily into its other position, so
"as not to be inconveniently-in-the way.
Having thus particularly described my said Invention, and the manner
of performing the same, I have to state that I do not restrict myself to
the preciso details herein described and delineated; but that what I.

page_text: believe to be novel and original, and claim as the Invention secured to
me by the herein-before in part recited Letters Patent, is,-
1. The fitting of the Hanson potato digger with improved means,
substantially such as are herein-before described, for preventing the
choking of the fork wheel (2, 3,) and shank (5).
2. The attaching of the shank (5) of the sock or shovel by means of
an improved adjustable holder, substantially such as is herein-before
described.
In witness whercof, I, the said John Wallace, have hereunto set
my hand and seal, this Thirtieth day of December, in the year
of our Lord One thousand eight hundred and seventy-four.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
JOHN WALLACE. (L.S.) ·