AN IMPROVED ROTARY SPADER OR DIGGING MACHINE
Year: 1872

page_text: LETTERS PATENT to John Thomas Brown Porter, of Lincoln, in the
County of Lincoln, Civil Engineer, for the Invention of “AN
IMPROVED ROTARY SPADER OR DIGGING MACHINE."
Sealed the 6th Decvember 1872, and dated the 17th June 1872.
COMPLETE SPECIFICATION filed by the said John Thomas Brown
Porter at the Office of the Commissioners of Patents, with his
Petition and Declaration, on the 17th June 1872, pursuant to the
9th Section of the Patent Law Amendment Act, 1852.
TO. ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
THOMAS BROWN PORTER, of Lincoln, in the County of Lincoln, Civil
Engineer, send greeting.
WHEREAS I am in possession of an Invention for "AN IMPROVED
ROTARY SPADER OR DIGGING MACHINE," and have petitioned Her Majesty
to grant unto me, my executors, administrators, and assigns, Her Royal
Letters Patent for the same, and have made solemn Declaration that
I am the true and first Inventor thereof.
NOW KNOW YE, that I, the said John Thomas Brown Porter, do
hereby declare that the following Complete Specification, under my

page_text: hand and scal, fully describes and ascertains the nature of the said
Invention, and in what manner the same is to be performed in and by
the following statement, reference being had to the accompanying
Drawings forming a part of this Specification :-
My Invention relates to rotary spading or digging machines, and
more particularly to improvements in the machine forming the subject
of the Invention for which Letters Patent were granted to Edwin
Addison Phillips, bearing date the 10th day of March A.D. 1865,
No. 671. This machine, as described in the said former Specification,
has a series of spading blades or tines connected to the travelling
wheels, and so controlled by fixed cams that as the machine moves
forward they are caused to rotate around the shaft or axle of the said
whicels, and enter the ground, thereby lifting, breaking, and pulverizing
the soil.
My present Invention when applied to the said machine will render
the same more generally efficient and convenient than heretofore. The
said Invention consists chiefly in novel contrivances applied in com-
bination with the travelling wheels and digging mechanism for raising
the latter from the ground, so that the machine may be readily adjusted
to be drawn from place to place along roads or other ways, or moved
from one part of a field to another part without digging. The said
Invention also consists in the peculiar construction of parts of the said
machine, which I will now proceed more fully to describe by the aid
of the accompanying Drawings. I construct my improved machines
either single or double and of any required width, and I adapt them
for either horse or steam power. For the double or large machine I
prefer to employ steam power.

page_text: The said machine is constructed with strong travelling wheels a
which support the entire machine when the same is in the position
shewn in Figure 3. These wheels are fitted to turn upon the
eccentrics b. The said eccentrics are fixed on a shaft or rod c which
is supported to turn freely in bearings d at each side of the machine.
These eccentrics are provided with levers b', which by the mechanism
herein-after described or in any other convenient manner are operated
to adjust the said eccentrics, and thereby raise or lower the machine.
The said eccentrics have double flanges b³, b³, the outer flange ³ being
made removable to permit the wheels to be readily put on or taken
off; e, e, are two side pieces or cheeks of cast iron or other suitable
material, and e¹ is a similar piece or check at the centre of the machine;
ff are the fixed cams which have bosses or hubs f* for the shaft or
rod c to pass through, and which are secured to the said checks by
screw bolts f²; g, g, are the curved bars, which in combination with
the said cams control the action of the spading blades k and force
them into the ground as the machine is drawn forward. These curved
bars are also secured at their upper ends to the cheeks e, e', by bolts h',
and at their lower ends they are held and supported by the bars
which are secured to the framework of the machinc, as shewn.
1
The wheels or discs which carry the shafts or bars ; whereon the
spading blades are fixed, are formed on or attached to long hollow
shafts or tubes which is fitted to turn freely on the eccentric shaft
or rod c. When the machine is adjusted to the position shewn in
Figure 4 and drawn forward, these shafts j revolve around the central
shaft c, and the successive rows of the blades k in revolving are forced
into the ground, as described in the said former Specification; but
when it is desired to take the machine from one field to another, along
a road or other way, or if it has to be turned around or moved along
the field, or upon any other ground without digging, the eccentrics are
adjusted by the levers b¹ and the mechanism connected therewith to
raise the machine into the position shown in Figure 3, wherein the
spades are quite clear of the ground, the machine being then easily
drawn along on the wheels a.
In light machines only one lever b' will be necessary, and the same
may be operated to make the required adjustment by hand, a spring
catch being provided to secure the said lever when the machine is
raised; but in large machines I employ the contrivance shown in

page_text: P
the Drawings, that is to say, the levers b¹ are connected to the chains &
which pass over the chain wheels m, m². The wheels m are fixed on a
shaft m² which by the bevel wheel and pinion n, o, is geared in connection
with the shaft whereon is fixed the hand wheel p'. The driver by turning
this wheel will cause the chain to travel between and around the chain
wheels and carry the levers with them, thereby effecting the required
adjustment of the machine. q is a brake wheel fixed on the shaft m²;
the brake band q is connected to the treadle lever whose fulcrum is
at is a ratchet wheel fixed on the same shaft; a pawl attached
to or operated by the end of the lever r is arranged to take into the
teeth of the said ratchet wheel. When the machine is to be turned
around or to be moved only a short distance in the field, the said pawl
is thrown out of gear with the ratchet wheel, and the driver after raising
the machine keeps it in the required position by applying his foot to
the brake lever r; but when the machine is to be moved across a
large field, or taken from one field to another, the pawl is thrown in
gear and the machine when raised will be held by the said pawl till
brought to the place where it is to recommence digging, when by
simply raising the pawl from the ratchet wheel the required adjustment
is effected. When the machine is to travel a great distance along a
road, say from one farm to another, it will require additional means for
retaining it in the required position, and for this purpose I employ
bolts passed through the levers b₁ into the framework. These con-
trivances are only required in the large machines; the aforesaid spring
catch will be sufficient at all times for the small machines.
The fixed cams are constructed with their lower or main part ƒ³ of
iron or steel, and their upper part f* of wood. Or I make the entire
cam of iron or steel, and form in the upper surface a groove wherein
I insert a strip of india-rubber. The wood or the india-rubber will
obviate to a great extent the breaking and loosening of the cranks,
which frequently occur when the cam is made entirely of metal.
Moreover the noise of the working of the machine is thereby greatly
diminished. The large machines, which are intended to be worked
by steam power only, are attached to the engine, when a traction
engine is used, by a long bolt u passing through two eyes on the
frame of the machinc. When a stationary engine and rope are
employed, the machine must have a small wheel in front for guiding
or steering it, and also for supporting the front end of the machine.

page_text: The small machines are drawn by horses, and are provided with suitable
shafts for that purpose.
Having thus fully described my said Invention, and the manner of
performing the same, I wish it understood that I claim,-
First. In a rotary spading or digging machine the eccentrics provided
with levers or other suitable adjusting contrivances in combination
with the travelling wheels for raising and lowering the said machine,
as herein set forth.
.
Second. The two eccentrics fixed on a shaft or rod which extends
across the machine through hollow shafts that carry the spading
blades, in combination with a lever or levers for adjusting the said
cccentrics, and with the endless chain and mechanism connected there-
with for operating and securing or holding the said lever or levers, as
herein set forth.
Third. Fixing the curved bars on the side pieces or checks and the
centre piece or check, so that the said bars act in combination with the
fixed cams, as herein set forth for the purpose specified.
Fourth. The novel construction of the said cams, as hercin set forth
for the purpose specified.
Fifth. A spading or digging machine constructed with a series of
rotating spading blades, controlled and forced into the ground by cams
and guide bars, and arranged in combination with the eccentrics and
their adjusting and securing mechanism, as herein specified.
In witness whercof, I, the said John Thomas Brown Porter, have
hereunto set my hand and seal, this Twenty-eighth day of May,
in the year of our Lord One thousand eight hundred and seventy-
timo
fixed cams, as herein set forth for the purpose specified.
Fourth. The novel construction of the said cams, as hercin set forth
for the purpose specified.
Fifth. A spading or digging machine constructed with a series of
rotating spading blades, controlled and forced into the ground by cams
and guide bars, and arranged in combination with the eccentrics and
their adjusting and securing mechanism, as herein specified.
In witness whercof, I, the said John Thomas Brown Porter, have
hereunto set my hand and seal, this Twenty-eighth day of May,
in the year of our Lord One thousand eight hundred and seventy-
Witness,
W. ROB. LAKE,
8, Southampton Buildings,
London.
J. T. B. PORTER. (L.S.)