IMPROVEMENTS IN Apparatus FOR EXCAVATING LAND
Year: 1871

page_text: LETTERS PATENT to Frederick Henry Trevithick, of No. 29, Guildford
Road, S.W., Surroy, for the Invention of "IMPROVEMENTS IN Apparatus
FOR EXCAVATING LAND.”
Sealed the 14th November 1871, and dated the 14th June 1871.
PROVISIONAL SPECIFICATION left by the said Frederick Henry
Trevithick at the Office of the Commissioners of Patents, with his
Petition, on the 14th June 1871.
I, FREDERICK HENRY TREVITHICK, of No. 29, Guildford Road, S.W.,
Surrey, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN APPARATUS FOR EXCAVATING LAND," to be as follows :-
-
This Invention has for its object improvements in apparatus for
excavating land.
In order to form a railway cutting, a canal, or other similar excavation
I employ a series of excavating machines, each of which is provided with
an endless chain of dredging buckets passing around rollers mounted on
horizontal axes, and driven by an engine carried on the frame of the
machine. The chain of buckets dredges away from the front of the

page_text: machine a trench a few feet in depth, and of a sufficient width to allow
the machine to follow along in the trench as the work goes on. The
buckets discharge the material into a hopper from which it falls into
tubs supported by an endless carrying rope. The tubs are stationary to
receive their loads, and then pass on to the rope which is gripped by a i
suitable instrument. The endless rope passes around a pulley on the
frame of the machine, and this pulley is driven by the same engine that
works the excavating buckets. The rope extends to any convenient
distance beyond the bank on which it is desired to deposit the material,
and here it passes around another pulley on a pulley carriage which runs
along guide rails laid for it. The endless rope is supported at inter-
mediate points by resting on pulleys which are themselves hung from
As the
overhead wires or cords along which they are able to run.
machine advances the pulley carriage also moves on, and the endless
carrying rope is taken forward with them. The tubs containing the :
material are provided with a catch, and on the withdrawal of this
catch the tubs overturn or doors open and discharge the material.
By this means the discharge can be effected at any point along the
length of the endless carrying rope, and in this way the spoil bank is
raised.
In forming a canal or railway cutting these machines are worked in
sets, each set consists of a number of machines sufficient to cover the
width of the cut, and these are arranged in echellon, the leading machine
being in the centre, and the carrying ropes passing off to either side
to pulley carriages on rails laid parallel to the canal or cut.
The second set of machines follows the first in similar order and
increases the depth of the cut, and so set follows set until the desired

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourteenth day of June, in the year of
our Lord One thousand eight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Frederick Henry Trevithick, Her special
license that I, the said Frederick Henry Trevithick, my executors,
administrators, and assigns, or such others as I, the said Frederick
Henry Trevithick, 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 lawfully
might make, usc, exercise, and vend, within the United. Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "IMPROVEMENTS IN APPARATUS FOR EXCAVATING LAND," upon the
condition (amongst others) that I, the said Frederick Henry Trevithick
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 ·
Scal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Frederick Henry Trevithick, do
hereby declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained
in and by the following statement thereof, that is to say:-
This Invention has for its object improvements in apparatus for
excavating land.
. In order to form a railway cutting, a canal, or other similar exca-
vation I employ a series of excavating machines, each of which is
provided with an endless chain of dredging buckets passing around
rollers mounted on horizontal axes and driven by an engine carried on
the frame of the machine. The chain of buckets dredges away from
the front of the machine a trench a few feet in depth and of a sufficient
width to allow the machine to follow along in the trench as the work
goes on.
The buckets discharge the material into a hopper, from which
it falls into tubs supported by an endless carrying rope. The tubs are
stationary to receive their loads and then pass on to the rope, which is
gripped by a suitable instrument. The endless rope passes around a
pulley on the frame of the machine, and this pulley is driven by the

page_text: the full width, so that the bank is left in steps, as is seen in Figure 2.
On the left-hand side of the Figure the machine a is the outermost
machine of the set, making the fifth cut, whilst on the right-hand side
is shown the outermost machine of the set, making the last cut, or that
which brings the excavation to its full depth; b, b, are the carrying
ropes passing over the spoil banks to the pulley carriages c on the other
side, which as the excavating machines move or travel along the
railway & and keep opposite to them.
Figure 3 is a side view, and Figure 4 is a plan of the excavating
machine. It consists of a timber framing, a mounted on a bogie wheel
frame a¹ in front, and upon other axles and wheels as as shewn, it runs
upon rails and all the wheels may have flanges, or the flanges may be
omitted from the wheels near the middle of the machine. In front of
the frame a is an endless chain of dredging buckets 6 passing around
a tumbler or driving barrel 6' at the top of the frame, and over guido
rollers bª at the bottom; c is a hopper into which the buckets discharge
the material they raise; d, d, are tubs to receive the material from the
hopper and carry it away. When the tubs are standing suspended from
the landing bar e, a workman by means of the hand wheel c' opens the
hopper shoots c³ and so fills the tubs. The full tubs are then -pushed
along by another workman off the landing bar on to the travelling
rope, and the tubs are then carried away to be emptied. The rope ƒ
passes around a pully f¹ on the excavating machine, and another
similar pulley on the pulley carriage shewn in Figures 1 and 2. The
way in which the rope is supported in between these pulleys will bo
presently described. The rope pulley on the pulley carriage is mounted
on a block capable of sliding in guides, and it is connected with a
weighted lover which draws it along these guides until the rope ƒ is
strained tight. A workman stands on a platform on the pulley, carriago
and receives and starts the tubs. The pulley carriage is caused to travel
along the railway to keep it opposite or nearly opposite to the exca-
vating machine, by gearing the axis of the pulley with the carrying
wheel in such manner as to transmit to the wheels the slow motion
which they require..
The arrangements of the rope f and the carrying tubs & need not
be hero described in detail, as they are well understood and known in
connection with Hodgson's wire tramway, but the arrangements by
which the excavating machine is enabled to carry such an apparatus

page_text: along with it and to discharge the material raised by the buckets by its
means form part of my Invention; g is a steam engine, soy of about 14
horse power, it drives the excavating buckets, also the driving pulley f¹
of the rope f, and it propels the machine by driving the two hinder
axles. On the crank shaft of the engine is a belt pulley, and a driving
belt on it actuates the shaft k, from which by another belt the shaft i is
driven. A train of wheels clearly seen in Figure 4 transmits motion
from the shaft i to the tumbler or driving barrel of the chain of
excavating buckets. Returning to the shaft it will be seen to have
upon it a bevilled pinion ² driving a similar wheel on the axis k, and k
is a pinion on this axis gearing with a bevilled wheel on the axis of the
driving pulley f' of the carrying rope f; is an axis at the back of the
machine, it is driven by a belt from the crank shaft of the engine, and it
has upon it a worming keyed fast on the axis and gearing with a worm
wheel on an horizontal axis m which in turn has worms upon it gearing
with worm wheels on the axles of the carrying wheels. This method of
propelling the machine is employed to move it forward as the work
progresses. For travelling to and from the work a more rapid action is
obtained through the bevilled wheels and pinions n.
The rails on which the machine runs are framed together in short
lengths, and each length as it is left behind the machine -is picked up
and carried to the front. A. hook shewn at o is used for this purpose,
it runs upon a supporting and guide rail at the side of the machine.
The depth of the cut can be adjusted so as to maintain a level bottom
by the screw standard, which forms the centre of the bogie frame, or an
hydraulic ram and pump may be substituted for the screw standard.
The way
in which the rope ƒ is supported over the spoil bank is shewn
at Figure 5, where the bank is represented as it appears from the ex-
cavation; p, p, are stationary strained wires supported on posts, and on
these wires the rope supports g run. One of these rope supports adapted:
to run on one wire as shewn in side view at Figure 6, and in front at
Figure 7; Figures 8 and 9 are similar views of a rope support adapted
to run on two wires, and which may be used when the loads to be
carried are heavy or the spans' unusually great. The excavating machines
and the ropes fare clearly seen in Figure 5, and the posts which are
erected on the spoil banks to carry the strained wires parc shewn at h in
Figure 9, they may be made adjustable as is there shewn. When
the rope support 2 arrives at one of the posts 1 the post is lowered to let

page_text: it pass and another post is raised behind it, the posts being made
telescopic for the purpose. The tubs d are, as is seen in Figure 3,
mounted in a frame on studs & which are beneath the centre of gravity
of the tub when loaded, and a locking bolt prevents the tub capsizing.
This locking bolt is in connection with a long trigger handle, which the
Drawing does not show, it hangs below the bottom of the tub, and
when it is turned upwards the bolt is drawn and the contents of the tub
aro discharged. The tub rights itself and the weight of the trigger
handle causes the bolt to return. The trigger handle may be acted
on by hand, or it may be moved by coming against a wire strained
in such a position as to intercept it, as is indicated by the lines 8, 8, in
Figure 1.
Having thus described the nature of my said Invention, and the
manner of performing the same, I would have it understood that I
claim,―
1st. The combination of apparatus for excavating land, substantially
as described.
2nd. The construction of the excavating machine, with its dredging
buckets and tub carriers, substantially as described.
3rd. The arrangements by which the carrying ropes are supported
and caused to travel forward with the excavating machine, substantially
as described.
In witness whereof, I, the said Frederick Henry Trevithick, have
horeunto set my hand and seal, this Fourteenth day of December,
in the year of our Lord One thousand eight hundred and
seventy-one.