IMPROVEMENTS IN MACHINERY FOR SINKING SHAFTS OR PITS, AND FOR THE DRIVING OR CUTTING OP TUNNELS
Year: 1875

page_text: LETTERS PATENT to William Firth, of Burley Wood, near Leeds, in
the County of York, Esquire, for the Invention of "IMPROVEMENTS
IN MACHINERY FOR SINKING SHAFTS OR PITS, AND FOR THE DRIVING OR
CUTTING OP TUNNELS.”
14
Sealed the 11th May 1875, and dated the 2nd March 1875.
PROVISIONAL SPECIFICATION left by the said William Firth at the
Office of the Commissioners of Patents, with his Pétition, on
the 2nd March 1875.
I, WILLIAM FIRTH, of Burley Wood, near Leeds, in the County of
York, Esquire, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN MACHINERY FOR SINKING SHAFTS OR PITS, AND FOR THE
DRIVING OR CUTTING OF TUNNELS," to be as follows:-
-
This Invention has for its object improvements in machinery for
sinking shafts or pits, and for driving or cutting tunnels.
I employ a mining machine similar to that described in the Speci-
fication of a Patent granted to me and to others, No. 2977, in the year
1861. This machine consists of a carriage on which is mounted a com-

page_text: pressed air engine giving motion about an axis to a pick, so as to cause
it to strike upon the working face of the rock. In applying such a
machine for sinking shafts or pits I mount it upon a circular table with
guide rails upon it. The machine is able to travel around the table, and
as it travels it cuts a circular ditch or groove. In order that it may do this
the machine is somewhat modified, the pick arm working in a vertical
plane on the outer side of the machine. The table is suspended by
tackle, by which it with the machine upon it can be lifted and lowered
at pleasure. Before setting the machine to work the table is lowered to
the bottom of the pit or shaft, brought to a level bearing, and wedged or
otherwise secured so that it cannot shift. The circular ditch or groove
is then cut by the machine as already described, isolating a central block
of rock; the table with the machine upon it is then lifted and the
central block is blasted from a central hole or from several holes if
necessary. In this operation there is no risk of shattering the rock
forming the wall of the pit, as must occur, more or less, where
blasting is carried on without first isolating the mass to be blasted.
When the debris has been cleared away the table is again lowered and
secured, and the machine set in operation; so the work goes on. A
tunnel of circular section may be produced in a similar manner, the
table being then set upright and being furnished with appliances to hold
the machine upon the guide rails in the altered position. Where, as will
generally be the case, the form which it is desired to give to the tunnel
is not circular I make the upright table or shield to the form required,
and to be able to work into the angles I arrange the machine so that it
can work either right or left-handed, or separate machines may be
employed. The floor of the tunnel may be cut by machines similar to
my mining machine herein-before referred to.
In some cases to produce circular tunnels, pits, or shafts I employ a
machine which can turn around a central pivot, and which acts with a
pick working radially to the tunnel, pit, or shaft, producing a ditch or
groove isolating, as in the former cases, a central block which is then
blasted. The pick may have a loose point or tool consisting of a piece
of flat steel jumped up at the cutting edge keyed into a slotted hole
made in the pick or hammer bar. I sometimes dispense with the use
of the pick, and use the direct force of air or other fluids.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Firth in the Great Seal Patent Office
on the 1st September 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
FIRTH, of Burley Wood, near Leeds, in the County of York, Esquire,
send greeting.
WHEREAS Her most Excellent. Majesty Queen Victoria, by Her
Letters Patent, bearing date the Second day of March, in the year of
our Lord One thousand eight hundred and seventy-five, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said William Firth, Her special license
that I, the said William Firth, my executors, administrators and
assigns, or such others as I, the said William Firth, 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, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVE-
MENTS IN MACHINERY FOR SINKING SHAFTS OR PITS, AND FOR THE DRIVING OR
CUTTING OF TUNNELS," upon the condition (amongst others) that I, the
said William Firth, 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 William Firth, 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 machinery for
sinking shafts or pits, and for driving or cutting tunnels.
I employ a mining machine similar to that described in the Specifi-
cation of a Patent granted to me and to others, No. 2977, in the year

page_text: 1861. This machine consists of a carriage on which is mounted a com-
pressed air engine giving motion about an axis to a pick, so as to cause
it to strike upon the working face of the rock. In applying such a
machine for sinking shafts or pits, I mount it upon a circular table with
guide rails upon it. The machine is able to travel around the table, and
as it travels it cuts a circular ditch or groove. In order that it may do this
the machine is somewhat modified, the pick arm working in a vertical
plane on the outer side of the machine. The table is suspended by
tackle, by which it with the machine upon it can be lifted and lowered
at pleasure. Before setting the machine to work the table is lowered to
the bottom of the pit or shaft, brought to a level bearing, and wedged or.
otherwise secured so that it cannot shift. The circular ditch or groove
is then cut by the machine as already described, isolating a central block
of rock. The table with the machine upon it is then lifted and the
central block is blasted from a central hole or from several holes if
necessary. In this operation there is no risk of shattering the rock
forming the wall of the pit, as must occur, more or less, where
blasting is carried on without first isolating the mass to be blasted.
When the debris has been cleared away the table is again lowered and
secured, and the machine set in operation; so the work goes on. A
tunnel of circular section may be produced in a similar manner, the
table being then set upright and being furnished with appliances to hold
the machine upon the guide rails in the altered position. Where, as will
generally be the case, the form which it is desired to give to the tunnel
is not circular, I make the upright table or shield to the form required,
and to be able to work into the angles I arrange the machine so that it
can work either right or left-handed, or separate machines may be
employed. The floor of the tunnel may be cut by machines similar to
my mining machine herein-before referred to.
In some cases, to produce circular tunnels, pits, or shafts, I employ
a machine which can turn around a central pivot, and which acts with a
pick, producing a ditch or groove, isolating, as in the former cases, a
central block which is then blasted. I sometimes dispense with the use
of the pick and use the direct force of air or other fluids.
-
In order that my said Invention may be most fully understood, and
readily carried into effect, I will proceed to describe the Drawings here-

page_text: Figure 1 is a section of a pit in process of being sunk by machinery
arranged and combined according to my Invention.
a, a, are circular rails fixed upon a strong table somewhat smaller in
diameter than the pit. The table rests when at work on the bottom of
the pit or on chocks inserted to give a more level bearing..
The mining machine consists of a carriage 6 mounted on wheels
running on the rails a, and there are also claws, not shown in the
Drawing, which descend beneath and hold the machine down to the
rails. c is a compressed air engine on the bed of the machine, giving
motion by means of a connecting rod to a lever on the horizontal
shaft d, on which is fixed the pick e. An elevation of a portion of the
construction is shown at Figure 2. The valve of the engine is arranged
and worked as in the machines which cut horizontally, and the forward
motion is obtained by rotating one or more of the carrying wheels by
means of a worm and worm wheel. If desired one of the rails and one
of the carrying wheels may be cogged on the face.
When the circular ditch has been cut to the required depth, the table
is lifted by means of the winding apparatus at the surface, and the
isolated central block is broken up by blasting or otherwise. Only small
blasting charges will be required.
Figure 3 is a horizontal section, Figure 4 is an elevation, and Figure 5
is a transverse section of another arrangement differing from that above
described in that the mining machine works beneath the table which is
carried by beams let into the sides of the pit. .
Jam screws pressing against the pit sides are also employed to steady
the table, as is seen in Figure 5. As before mentioned a circular tunnel
either horizontal or inclined may be cut by means of similar mechanism,
the table then being set up on edge.
Figure 6 is a side elevation, and Figure 7 a rear elevation, both partly
in section, of tunnelling machinery adapted to cut a large tunnel of
ordinary form. a is the table or shield built of wrought iron, it is
carried upon two pairs of wheels b, b, running on rails c, c, one on either
side; the rails are mounted upon girders which are fixed upon the lining
5 of the tunnel. The table or shield is suspended from the wheels 6 in

page_text: DIG ALLUVIOIery for Downey Dnajes, go.
such manner that it can be raised and lowered at pleasure, to give to the
mining machines d, d', a command of every portion of the working
face.
In addition to the machine or machines d which cut the sides of the
tunnel are other machines & traversing on horizontal guides across the
shield to groove the face at such intervals as may be considered desirable;
the lowest machine of this series cuts the floor of the tunnel. The
machines are all supplied by flexible tubes with air under pressure drawn
from an air main.
Figure 8 is a side elevation, Figure 9 is a plan, Figures 10 and 11 are
end elevations of a machine for cutting small tunnels or headings by
means of a machine which can be carried around a central pivot. The
machine shown is adapted to cut a square heading, but it will be obvious
that a machine of similar design but simpler construction may be made
to cut a circular heading, or a shaft or pit. a is a heavily loaded wagon
with the stiff shaft 6 projecting from it in front. Around the shaft 6 the
table c can be rotated by means of a worm and worm wheel, not shown
in the Drawings. On the table is a slide d, it can be traversed by means
of a hand wheel and screw e. The slide carries an air engine working a
pick which can be set to work either about the centre 9, as the
Drawings show, or about the centre h, thus the pick can be made to
operate either to the right or left hand. Each side in turn is worked as
far as the pick can get at it without being taken out and reversed, the
traverse or feed motion being given by means of the screw e, and the
change from side to side by rotating the table c about the shaft b.
When each side of the heading has been partly cut, the pick is reversed,
and the cutting is finished, the wagon and machine is then drawn back,
and the isolated block is wedged down or otherwise removed. For a
circular heading or pit a similar rotatory motion about the shaft 6 will
suffice without the table c and slide d.
Having thus described the nature of my said Invention and the
manner of performing the same, I would have it understood that I do
not confine myself to the details of the arrangements described, but I
claim,―
The combination of machinery for sinking shafts or pits, consisting of a
a table with a mining machine arranged to cut a circular ditch whilst
traversing around the table, substantially as described.

page_text: I also claim the combination of machinery for driving or cutting
tunnels, consisting of a table or frame with a mining machine arranged
to cut a groove whilst traversing around the table or frame, substantially
as described.
I also claim the combination of machinery for sinking shafts or pits,
and for driving or cutting tunnels, consisting of a central pivot with a
mining machine arranged to turn around the said pivot, and to cut a
groove around it, substantially as described.
In witness whereof, I, the said William Firth, have hereunto set my
hand and seal, this Twenty-fourth day of August, in the year of
our Lord One thousand eight hundred and seventy-five.
WILLIAM FIRTH. (L.8.)