Improvements in I
Year: 1889

page_text: Improvements in
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co., Patent Agents,
Southampton Buildings, in the County of Middlesex 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:—
This invention relates to potato diggers, and the invention consists in the improved
construction, arrangement and combination of the different parts, all as hereinafter
described.
In the accompanying drawings
Figure 1 is a plan view of the improved potato digger.
Figure 2 is a vertical central longitudinal section thereof on the line X X in
Figure 1.
Figure 3 is a front elevation of the plough and rotary cage, raised up as they
appear when out of oporation.
Figure 4 is a plan similar to Figure 1 but with the raising and lowering device of
the cage and plough and with the driving connection of the cage left out.
Figure 5 is a rear elevation of the potato digger.
Figure 6 is a side elevation of the same with one of the ground wheels
omitted, and
Figure 7 is a vertical section on line Y, Y, of Figure 2.
A is the frame of the digger which supports the operating parts; B is the drive-
axle journalled transversely in suitable bearings on the frame.
Care two ground wheels, loosely revolving on the axle, and supporting the
machine; D are ratchets fast upon the axle, and provided with suitable dogs to
connect the ground wheels with the ratchet if desired to revolve the axle with the
wheels.
'

page_text: E is a tongue to which the horses are hitched, and this is pivotally secured at a,
and vertically adjustable at b, so as to change the line of draught in its vertical plane
by raising or lowering the tongue at 6 preferably by means of a suitable hand-lever c,
which is within reach of the driver on his seat.
F is a vertical guide bearing. secured to one of the side bars of the frame. G is the
standard of the plough, slidingly engaging with its vertical portion into the guide
bearing F. The lower end of this standard extends laterally and forms a shoo G upon
which the plough is secured.
The plough His substantially of the nature of a scoop shovel, and is provided with
a suitable large middle share to dig under and scoop up the potato hills, and this
share has preferably a point d and its front edge d is set at an angle to the line of
draught. Suitable inclined sides ƒ and g retain the ground on the plough, and direct
it to the rear as the plough advances.
A rotary cylindrical cage or screen is mounted in rear of, the plough to receive the
ground and separate the potatoes therefrom. The cage consists of an annular head or
ring I, and of spiral rods, or spring tines J, secured to the ring in any suitable
manner, and projecting rearwardly, whereby they form a spiral cage as shown.
The ring I has an outwardly projecting annular flange h, and is provided circum-
ferentially with these sprocket teeth i. Upon the inner face the ring forms suitable
bearings for the roller K on which the cage is supported clear of the ground above
its vertical centre or nearly so.
In addition to this supporting inside roller, there are three more rollers I, I,
and L, suitably grooved to engage with the flange H on the outside of the ring, to
firmly hold the cage in a position free to revolve on its axis. The rollers L and L
are secured to the frame by means of suitable hangers K, and engage with the
flange H upon the two opposite sides, so as not to interfere with the free raising and
lowering of the cage, and the roller L" engages with the flange h centrally above
the cage, and is mounted upon a shaft M. This shaft M lies parallel to the axis of
the cage, and revolves in suitable bearings secured to the hinged frame N. This
frame is hinged at m to the main frame, and, projecting laterally above the same,
has its free end secured in any suitable manner, such as by a rope or chain n to the
winding roller o on the rock shaft O, whereby it is risingly and fallingly supported.
The rock shaft O is stationarily journalled in suitable bearings upon the main
frame, and is actuated by the hand-lever P secured thereon in proximity to the seat
of the driver.
A toothed segment Q is secured upon the rock shaft, and this engages with a
rack p formed on the upper end of the plough standard at the rear edge thereof.
A suitable notched quadrant R is provided in connection with the lever P to adjust
said lever by means of its spring pawl into any desired position as in the usual manner
of constructing such devices.
The winding roller o is adjustably secured to the rock-shaft O, preferably as shown
in Figure 7, wherein said winding roller is placed loosely upon the shaft, and provided
with a laterally projecting spur which engages with one of a concentric series of
adjusting holes formed in the side of the fixed collars which is secured upon the
rock shaft. A suitable nut t upon the end of the rock-shaft holds the winding roller
into its adjusted engagement with the collar s.
The shaft M has secured upon it the sprocket wheels S, and a chain T passes
.around this sprocket wheel and the sprockets on the head of the cage to communicate
motion to the cage.
Another sprocket wheel u on the shaft M engages with a sprocket chain v which
transmits motion from the axle of the potato digger to the shaft M.
To this end a bevel gear wheel is fastened upon the axle; this engages with the
bevel pinion on a shaft w which is also provided with a sprocket wheel. The
sprocket chain V passes around the sprocket wheels ", u, and over two idlers w
and w' suitably supported upon the main frame to change the direction of the sprocket
chain unto the shaft M, so that the chain will not bind when the hinged frame N is
raised or lowered.

page_text: t
.
The supporting roller K of the cage is secured to a hinged frame N₁'. which is
hinged correspondingly to the frame N, but independently below the same, and is
supported in position parallel, or nearly so, to the frame N by the hanger N,
connecting the two frames.
The roller L' is provided with a scraper and a similar scraper is provided in
proximity to the supporting roller K to clean the bearing of this roller on the head
of the cage in advance of said roller. As the arrangement and construction of the
different parts throws the forward end of the cage to one side, I preferably mount
the cage at an angle to the line of draught to bring its rear into the centre again.
In practice, the parts being constructed and arranged substantially as described
and shown they are intended to operate substantially as follows.
The driver from his seat has control of the lever P; by disengaging said lever
from its notched quadrant R, he can throw it forward or rearward to simultaneously
lower or raise the plough and cage. The plough is lowered into the ground or raised
from the ground through the medium of the toothed segment Q, engaging into the
rack of the plough-standard, while at the same time, the cage is raised or lowered
correspondingly thereto by the winding or unwinding of the chain or cord n on the
winding roller o which risingly or fallingly actuates the frames N and N³, the latter
carrying the cage by means of the supporting roller K. The larger degree of move-
ment necessary to raise or lower the plough than is required for the cage is effected
by making the radius of the winding roller o less than the radius of the segment Q
say one half; thus if it be necessary to raise the plough six inches to bring it clear
of the ground the cage will raise three inches, as the cage has to be in its operating
position in proper juxtaposition to the rear end of the plough so as to cause the
dirt to pass from the plough into the cage, it is necessary to provide an independent
relative adjustment between the plough and the cage to restore the proper relative
position between them if the plough is required to dig at a different depth from the
one to which it is adjusted, and to this end the winding roller o is adjustably secured
upon the shaft.
In digging potatoes, motion is communicated to the axle by having the dogs of
the ratchets D thrown into gear. From the axle the motion is then communicated
to the shaft w through the medium of the gear wheels v and v and from the shaft w
motion is then communicated through the medium of the sprocket chain V to the
shaft M and from the shaft M the motion is imparted to the sprocket chain I around
the head of the cage. This sprocket chain is merely tight enough to communicate
motion to the cage, but does not support the weight of the cage and a suitable
tightener sprocket w may be secured to the hinged frame N¹ to adjust the chain to
operate in this manner.
As the plough digs under the potato bills in advance of the cage, all the dirt and
potatoes are together carried up and over the shovel of the plough into the cage.
As the share of the plough is provided with the upturned sides g the ground is
prevented from being pushed off the sides of the share, and to leave a clear path for
the full width of the cage without carrying more ground into it than is necessary, an
outside scraper H₁ is secured to the plough to throw the ground and weeds out of the
way of the cago.
As the plough gradually assumes towards its rear end the circular shape corre-
sponding to the head of the cage the ground is readily carried into the cage without
choking.
As fast as the dirt with the potatoes is discharged into the cage, the rapid revolu-
tions of the latter will effect the separation, the ground passing through the interstices
between the tines, and the potatoes rolling out towards the rear. The necessary
incline to effect the proper separation is controlled by the driver through the medium
of the lever c in front of him, by means of which he can tip the cage to adjust it
for ploughing up or down hill."
Having now described the construction and operation of the potato digger, I will
more specifically point out the improvements accomplished and the advantages.sought
to be obtained thereby. .

page_text: With
The use of spiral tines increases the length of space for separating the earth or
dirt from the potatoes before the latter pass out at the rear end of the cage without
lengthening the cage, at the same time, the latter acts as a screw to pass the dirt to
the rearward as soon as it passes into the tines. This action is especially desirable to
keep the cage free from weeds and to offect a positive discharge at the rear.
straight tines, or tines substantially so, the discharge would depend altogether on a
given rearward incline, either by setting the tines more or less outwardly, or by
dipping the cage to the rear; this is undesirable as it is difficult to maintain the
incline always on uneven ground because the cage has to be set higher to revolve free
from the ground.
The previous application of rotary cages or screens for separating the potatoes from
the ground, the material was carried around the inside, and also, as the dirt passed
out between the tines, a portion would be carried up the outer circumference, and
was liable to be thrown all over the working parts of the machine, raising a cloud of
dust in dry soil to the great discomfort of the driver. The present construction
entirely overcomes these objections, as the inner face, as well as the outer face, and
the interstices between the tines, all have the same action of screwing the dirt to the
rear, and the carrying over and spreading of the soil over everything is thus avoided.
The potatoes, and other material which cannot pass between the tines are positively
discharged at the rear, and in a small space from which the potatoes can be picked
up with half the labour.
By placing the axis of the cage at an angle to the line of draught as shown, the
potatoes will be deposited in the centre of the machine, so that they will not be in the
path of the wheel in digging the next row; but other advantages are obtained,
whereby it will be seen that the potatoe hills as they pass into the cage are torn up
diagonally across as the junction between the plough and the cage is not at right
angles to the line of draught.
By making the tongue vertically adjustable under the control of the driver, I am
enabled to adjust the plough to the conditions of the ground as for instance, when
operating in wet and sticky soil, I am enabled by raising the tongue to throw the
plough at a squarer angle against the soil, and the result is to get a harder
pressure against the face of the plough, by means of which I am enabled to produce
a scouring action upon the plough, which keeps the share clean even in the most
sticky soil.
1 have also found by experience that the altered adjustment of the cage obtained by
changing the incline of the plough is necessarily required for the cage to meet the
same conditions of soil, as when the dirt is wet and mucky it should remain in a
cage a longer time so as to ensure a separation of the earth from the potatoes before
the material can pass out at the rear. In light soil the reverse adjustment will meet
the best conditions of operation.
In going up or down hill the potatoes may be prevented from rolling out of the
cage by adjusting the line of draught up or down.
I am aware that the vertical adjustment of the frame to or from the tongue of
the machine is old of itself but the peculiar construction of my frame carrying
the plough and cage, and, having its adjustment in relation to the line of draught
under the control of the driver is a peculiar advantage of my machine.
Although the plough and cage are independent of each other, hoth adjust in
vertical line, thus their proper relative position to each other is readily maintained,
and the construction and operation is greatly simplified. If desired at any time the
relative adjustment between the plough and the cage may be changed by means of
the adjustability of the winding roller o, as it will be seen in Figure 7 that after
unscrewing the nut t, the winding roller may be disengaged from the collars and
turned backward or forward upon the shaft O and be engaged into another adjusting
hole in the collar s. The winding roller is provided for the purpose of easy adjust-
ment with a handle o' to give the necessary purchase for raising the weight of the
cage. The toothed segment Q which lifts the plough out of its engagement with
the standard is also adjustably secured upon the shaft O by means of a set-screw, or

page_text: otherwise so as to adjust the plough independently of the cage: By these adjust-
ments, the relative position of the cage to the plough can be obtained at any desired
depth of digging for which it may be desired to adjust the plough.
The arrangement of the two frames N and N¹, to lift the cage, is also of particular
advantage. The connection with the lever P lifts the upper frame N, and the
langer N connecting the upper and lower frames, lifts the lower frame which carries
the roller K on which the cage is supported; thus in raising the cage the roller K
lifts the cage vertically or substantially so within the limit required.
By this arrangement the cage raises and lowers freely without any liability of
straining the chains, or binding the cage within the rollers.
The manner of supporting and revolving the cage is very important, as all obstruc-
tions on which the vines or weeds are liable to catch, or in which the dirt or stones
may lodge, have to be absolutely avoided, and as the work of revolving the cage full
of material is very heavy, all friction, or liability to create it, must be avoided. This
object is obtained in a very perfect manner by supporting and holding the cage
altogether by rollers, which form anti-friction bearings, whilo, at the same time, their
application on the outside and on the top of the cage removes them from any possi-
bility of becoming entangled with weeds or vines, or obstructed by dirt or stones, and
the application of scrapers, where required, easily removes the sticky ground. These
features enable the machine.to be used no matter how full of weeds, vines or stones a
field may be, or how wet or sticky the soil is to work in. There is not a single
projecting corner or obstructing bearing in the improved digger within the reach of
weeds. The driving chain V can run with a slight slack, and it is not liable to bind if
dirt should get between the head of the cage and the chain.
The manner of carrying the motion by means of the chain V from the shaft w to
the shaft M permits of the free raising and falling of the frame N in raising and
lowering the cage. The advantage of raising and lowering the plough and cage
jointly by one lever only during the work of ploughing, greatly fascilitates the work
of the driver, and simplifies the construction, the independent adjustment being but
rarely required.
By setting the cage at an angle to the line of draught, I gain another point, namely,
I can use a plough which approaches more nearly the ordinary plough that is, one
having a mold-board, the lower or cutting edge of which recedes from the edge of the
plough. Such a plough requires much less draught for digging than the ordinary
scoop plough. My plough differs from the ordinary plough mainly that, instead of
the mold-board, I have a plough-share which raises the ground instead of turning it,
but its digging edge recedes from the edge of the plough. If this plough share were
cut off at its rear edge at right angles to the line of draught it would be found to be
much higher near the standard than at the opposite side. By stopping it off at its
rear edge, at an angle, said rear edge will correspond with the circular shape of
the cage.
By securing the tines of the rotary cage at their front ends only, the spaces between
them are entirely free from front to rear and no chance is afforded for the potato vines
or weeds to become entanged in the cage.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed as communicated to me
by my foreign Correspondent I declare that what I claim is :-
First. In a potato-digger, a rotary screen consisting of an annular head and tines
secured thereto, and projecting rearwardly therefrom, entirely free and independent
of each other, substantially as described.
Second. In a potato-digger, the combination of a rotary screen consisting of an
annular head, tines secured thereto and projecting rearwardly therefrom entirely free
and independent of each other, a rising and falling frame carrying a roller upon which
the head of the screen is supported, an outwardly projecting flange on the head of the
screen, and grooved guide rollers engaging therowith, on opposite sides, substantially
as described.

page_text: Third. In a potato-digger the combination of a rotary screen, a rising and falling
frame carrying a roller upon which the head of the screen is supported the drive-shaft
journalled upon said frame, and provided with a sprocket wheel, and a driving chain
around said sprocket wheel and the head of the screen, substantially as described.
. Fourth. In a potato-digger, the combination of the wheeled truck or frame, the
rotary screen circumferentially supported by rollers, and consisting of an annular
head and tines secured thereto free and independent of each other, the drive chain
around the head of the screen and the digging plough in advance of the screen, sub-
stantially as described.
Fifth. The combination in a potato-digger, of the revolving screen, the rising and
falling frame N on which the shaft M is mounted, the drive-chain passing around the
sprocket wheel on said sliaft and the head of the screen, the rising and falling
frame N¹ carrying the roller K, on which the screen is supported, and the raising and
lowering connections of the frames N, N' with the rock sliaft O and lever P, sub-
stantially as described.
Sixth. The combination with the supporting wheels axle and frame of a potato-
digger, of the rock-shaft mounted on top of said frame, and provided with a raising
and lowering lever, of a digging plough risingly and fallingly supported by actuating
connection with said rock-shaft, and the revolving screen risingly and fallingly
supported by actuating connection with the same shaft, substantially as described.
Seventh. In a potato-digger, the revolving cylindrical cage consisting of the annular
head and spiral tines secured thereto, and with their rear ends unsupported, said cage
being adapted to operate as a screw-discharge, substantially as described.
Eighth. In a potato-digger, the combination with the digging plough of the
revolving screen mounted in the rear of said plough at an angle to the line of draught
substantially as described.
•
Ninth. In a potato-digger, the combination with the revolving screen, of the digging
plough mounted in front of said screen, and consisting of the standard G risingly and
fallingly secured to the frame of the plough the central share H having the cutting
edge and the point d, the upturned sides fand g, and the outside scraper H³, sub-
'stantially as described.
Dated this 16th day of March 1980