Year: 1889

page_text: I, JAMES ARTHUR LEWIS, of Hassall, near Sandbach, in the County of Chester,
Agricultural Machinist, do hereby declare the nature of this invention and in what
manner the same is to be performed to be particularly described and ascertained
in and by the following statement:-
My invention relates to potato digging machines of the kind known as "Hanson's
potato digger" in which a rotary fork arranged behind the digging share or blade is
employed to spread the soil of the ridge and to separate the potatoes therefrom.
The object of my invention is to spread the ridge and separate the potatoes from
the soil more effectually than heretofore and with less injury to the roots, and to this
end it consists essentially in substituting for the rotating fork what I term a screen
wheel which, instead of striking the ridge with sufficient speed and force to throw
the soil and potatoes laterally carries the potatoes to one side.
In the accompanying drawing,
Figure 1 is a rear elevation of so much of a potato digging machine as is necessary
to show the application of my invention thereto, and,
Figure 2 is a side elevation of the same.
a is a portion of the frame of the machine; b is the driving axle, and c, c are the
driving wheels.
.d is the screen wheel which is mounted upon the shaft e driven from the axle b
through the medium of the bevel wheel fand pinion g.
is the digging share or blade the curvature of which corresponds to the periphery
of the screen wheel d. The said share is carried by the leg h¹ which is secured by the
clips 2 to the frame a. It will be noticed by reference to Figure 2 that the portion
of the said frame to which the leg is attached is curved so that by varying the position
in which the leg is clipped the angle of the share will be correspondingly varied to
suit different kinds of soil.
The screen wheel d consists essentially of a hoop or ring i of say 46 inches in
diameter connected to a hub j by spokes k, k (the said spokes being curved as
shown in Figure 2 so as to offer as little obstruction as possible to the entrance
of the soil into the wheel) and of teeth or rods 1, 1 of say ten inches in length secured
to the said ring by nuts m, m or by any other suitable means.

page_text: The said teeth or rods are advantageously and preferably inclined backward from
the direction in which the wheel d rotates, and downwardly as shown, but they
may be arranged in any other convenient manner provided they constitute a kind
of screen or grating.
Instead of mounting the wheel d upon the shaft e as hereinbefore described it
may be mounted upon friction rollers and driven by any desirable mechanism.
In the operation of my improved machine it will be understood that as it advances
the share passes under the ridge so that the soil is forced into the screen wheel where
it is screened and riddled the potatoes being carried to one side.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
(1) In a machine of the kind herein before described for digging potatoes the
combination with the digging share or blade of a wheel into which the soil and
potatoes are passed from the said share or blade the said wheel being constructed to
form a kind of grating or screen, substantially as and for the purpose set forth.
(2) The manufacture and use of the improved potato digging machine bereinbefore
described and illustrated in the accompanying drawing.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London,
Agents for the Applicant.