IMPROVEMENTS IN MACHINERY FOR DRIVING DRIFTS AND SINKING SHAFTS. THROUGH STONE OR ROCK
Year: 1871

page_text: LETTERS PATENT to Edward Alfred Cowper, of No. 6, Great George
Street, Westminster, in the County of Middlesex, for the Invention
of "IMPROVEMENTS IN MACHINERY FOR DRIVING DRIFTS AND SINKING SHAFTS.
THROUGH STONE OR ROCK."
Sealed the 14th November 1871, and dated the 20th June 1871.
'
PROVISIONAL SPECIFICATION left by the said Edward Alfred Cowper
at the Office of the Commissioners of Patents, with his Petition, on
the 20th June 1871.
"
I, EDWARD ALFRED COWPER, of No..6, Great George Street, West-
minster, in the County of Middlesex, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN MACHINERY FOR DRIVING DRIFTS®
AND SINKING. SHAFTS THROUGH STONE OR ROCK," to be as follows:-
'
This Invention has for its object improvements in machinery for
driving drifts or sinking shafts through stone or rock. For this purpose.
I employ a series of jumpers or chisels separately actuated by means of
compressed air or steam and moved so as to produce chases or grooves,
in the rock.parallel or nearly parallel to each other, the portions of the

page_text: stone or rock remaining uncut between the grooves being subsequently
knocked away by hand or by mechanical means. The chisels or jumpers
act by striking the rock a succession of blows rapidly and continuously
repeated, a small advance only of the chisel sideways taking place
between the blows. The portions of rock remaining uncut between the
grooves can be broken down with hammers, levers, or wedges by hand
or by wedges actuated by the machine.
One mode of carrying out this Invention consists in the arrangement
of a number of machines carrying chisels or jumpers on a vibrating
frame, the machines being placed close to each other.
Each machine consists of a cylinder having a piston working in it,
and to the end of the piston rod is attached a chisel having one or more
cutting edges, the reciprocating motion of the piston is produced either
by the action of steam or compressed air, the chisels or jumpers do not
rotate on their own axes but have only a backward and forward motion
in the direction of their length, and the vibrating frame which carries
the machines is caused to vibrate either by manual labor or by power
through the intervention of two wire ropes or other suitable known
mechanical means so as to make the chisels or jumpers cut grooves or
chases in the rock, and the whole apparatus is slowly advanced by
means of a screw rack and pinion or other suitable known means whilst
the grooves are being cut.
Another form of the machine consists in the arrangement of a number
of such aforesaid cylinders with chisels or jumpers on a revolving head so
that the chisels of the machine produce a series of concentric grooves,
the whole revolving head being advanced by means of a screw rack and
pinion or other suitable known means as the grooves are cut. The
portions of rock left standing between the grooves. can be broken away
by wedges actuated by machines similar to those which work the chisels,
or they can be broken down by hammers, levers, or wedges by hand.
In some cases I use two vibrating frames carrying such aforesaid
machines operating either side by side or one above the other. The
frames may be hinged so as to vibrate either up and down or sideways,
and can be made of such size as to cut the grooves for the entire required
size of drift-shaft. The grooves may be either in horizontal, vertical,
concentric, or parallel lines, or in curved or zig-zag parallel lines. The
chisels may have 'cutting faces either parallel to each other or crossing
each other, or they may have faces of an H, Z, U, or other form.
•
1

page_text: As the rock operated upon by the chisels may vary in hardness I
control the action of the chisels according to the quality of the rock by
regulating the admission of air or steam to each separate cylinder by
plugs, cocks, or valves in the inlet passages conveniently under the
command of the man attending to the machine.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edward Alfred Cowper in the Great Seal Patent
Office on the 19th December 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
ALFRED COWPER, of No. 6, Great George Street, Westminster, in the
County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by. Her
Letters Patent, bearing date the Twentieth day of June, in the year of
our Lord One thousand eight. hundred and seventy-one, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Edward Alfred Cowper, Her special licence
that I, the said Edward Alfred Cowper, my executors, administrators,
and assigns, or such others as I, the said Edward Alfred Cowper, 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 "IMPROVEMENTS IN
MACHINERY FOR DRIVING DRIFTS AND SINKING SHAFTS THROUGH STONE OR ROCK,"
upon the condition (amongst others) that I, the said Edward Alfred
Cowper, 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 Edward Alfred Cowper, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the accompanying

page_text: Sheets of Drawings, and to the figures and letters marked thereon,
that is to say :--
This Invention has for its object improvements in machinery for
driving, drifts or sinking shafts through stone or rock. For this purpose
I employ a series of jumpers or chisels separately actuated by means
of compressed air or steam, and moved so as to produce chases or
grooves in the rock parallel or nearly parallel to each other, the portions
of the stone or rock remaining uncut between the grooves being sub-
sequently knocked away by hand or by mechanical means. The chisels
or jumpers act by striking the rock a succession of blows rapidly and 1
continuously repeated, a small advance only of the chisel sideways
taking place between the blows. The portions of rock remaining uncut
between the grooves can be broken down with hammers, levers, or
wedges by hand or by wedges actuated by the machine.
One mode of carrying out this Invention consists in the arrangement 1
of a number of machines carrying chisels or jumpers on a vibrating
frame the machines being placed close to each other.
Each machine consists of a cylinder having a piston working in it,
and to the end of the piston rod is attached a chisel having one or
more cutting edges, the reciprocating motion of the piston is produced 2
either by the action of steam or compressed air, the chisels or jumpers
do not rotate on their own axes but have only a backward and forward
motion in the direction of their length, and the vibrating frame which
carries the machines is caused to vibrate, either by manual labor or
by power through the intervention of two wire ropes or other suitable 2
known mechanical means, so as to make the chisels or jumpers cut
grooves or chases in the rock, and the whole apparatus is slowly advanced
by means of a screw, rack and pinion, or other suitable known means,
whilst the grooves are being cut.
Another form of the machine consists in the arrangement of a number
of such aforesaid cylinders with chisels or jumpers on a revolving head,
so that the chisels of the machine produce a series of concentric grooves,
the whole revolving head being advanced by means of a screw, rack,
and pinion, or other suitable known means as the grooves are cut. The
portions of rock left standing between the grooves can be broken away
by wedges actuated by machines similar to those which work the
chisels, or they can be broken down by hammers, levers, or wedges by
hand

page_text: In some cases I use two vibrating frames carrying such aforesaid
machines operating either side by side or one above the other. The
frames may be hinged so as to vibrate cither up and down or sideways,
and can be made of such size as to cut the grooves for the entire
required size of drift shaft. The grooves may be either in horizontal,
vertical, concentric, or parallel lines, or in curved or zig-zag parallel lines.
The chisels may have cutting faces either parallel to each other or
crossing each other, or they may have faces of an H, Z, U, or other form.
As the rock operated upon by the chisels may vary in hardness I control
the action of the chisels according to the quality of the rock by
regulating the admission of air or steam to cach separate cylinder by
plugs, cocks, or valves in the inlet passages, conveniently under the
command of the man attending to the machine.
DESCRIPTION OF THE DRAWINGS.
Figure 1 Sheet I. is a sectional plan of an apparatus constructed
according to my Invention, and arranged to cut chases or grooves in
horizontal lines; Figure 2 is a sectional elevation; Figure 3 a transverse
section, and Figure 4a back view of the same. A is the general frame of
the apparatus which can be moved backwards and forwards on guides
B, B¹, fixed at the top and bottom of the driftway. These guides are
adjusted on pieces of timber by set screws, and are prevented from
moving backwards by set screws catching into recesses in the sides of
the driftway. The frame is moved backwards and forwards on the
guides by the screw C fixed to the frame and working into the rack C¹
fixed to the bottom guides; the screw is turned by a ratchet D and may
be turned more rapidly for drawing the apparatus back by a double
cranked handle D³ provided with an universal joint, so that it can be
worked at a convenient height or lie when not in use on the bottom of
the driftway. The frame is further kept steady by a wheel E, capable
of adjustment, and which presses against the top or roof of the driftway,
a piece of plate being provided for it to move on. F is the vibrating
frame on which the cylinders G, G, G, of the separate drifting machines
are fixed, and it is connected by hinged joints H to the main frame A.
The frame F is provided with a projection or lever I, by which it is
caused to vibrate by a screwed rod J moved backwards and forwards by
turning the nut K, provided with cross handles and fixed in the back
end of the main frame A.

page_text: Each separate drifting machine consists of a cylinder G firmly fixed
to the vibrating frame F of a piston and piston rod L and a chisel or
jumper M fixed into the end of the piston rod L. The piston at the
back end has the full area of the cylinder, but at the front end an
annular area much smaller owing to the large piston rod, the compressed
air or steam acting on the large area to drive the chisel against the rock,
and on the smaller area to bring the chisel back. The chisel and piston
rod are prevented from turning on their own axis by a flat surface being
provided on one side of the piston rod, and the front hole in the cylinder
being made to fit it. The compressed air or steam is alternately
admitted to the front and back ends of the piston by one of two passages
connected to the valve box O by flexible tubes N, N, so as to allow for
the vibration of the cylinder, the valve box O being fixed to the main
frame A. These pipes and passages are alternately used for the entrance
and exit of the compressed air or steam, this being regulated by the
valve which is of the piston description. All the valves for the separate
machines are connected so that they can be driven by one cam P, but
the passages are so arranged that some of the pistons are going out
whilst others are coming in. The cam shown is one giving five strokes
of the machines for every revolution of the cam shaft Q which is turned
by a winch handle at the back of the apparatus. The cam is enclosed
in a frame R with rollers or trucks and the frame is connected by levers
S, S, to the valves so as to actuate them; T, T, T, are the three inlet pipes
for the compressed air or steam and there are three exhaust pipes
U, U, U, so as to avoid using one large pipe for the inlet and one for the
exhaust. The two chisels at the top of the driftway and the two at the
bottom are cranked somewhat so as to cut the driftway sufficiently large.
The passage into the back of each cylinder is provided with a small
valve so as partially close it if the piston should go too far forward,
as in the case of the chisel getting into a hole in the rock. The valve
has a rod which works in contact with a rod L' attached to the piston
rod L of the machine, and when the piston goes too far forward it
partially closes the valve. The rod attached to the valve has a ratchet
or friction ratchet arrangement by which the rod L' when the piston
is going back opens the valve a little every stroke till after about eight
strokes the valve is full open again. Cocks or valves may be also pro-
vided to regulate the supply of compressed air or steam to each cylinder,
so as to prevent one machine doing more work than the others if it is

page_text: working in a softer part of the rock. This machine may be placed in
the centre of a driftway and may be attended by two men at the front,
or it may be attended by one man only at the front when it will be
convenient to place it out of the centre of the driftway in order to give
the man more room, particularly when the great object is to drive the
driftway as fast as possible forward, when the less stuff that is cut away
the quicker the work will be performed.
Figure 5, Sheet II., is a plan of another form of apparatus constructed
according to my Invention, and arranged to cut vertical chases or
grooves; Figure 6 is a side elevation; and Figures 7 and 8 are front
and back elevations of the same.
A is the main frame of the apparatus, and is carried by the bed
plate B, provided with proper guides, in which the frame can move
backwards and forwards. The bed plate B is supported and adjusted on
the rough bottom of the driftway by set screws provided with lock nuts.
The frame A is moved backwards and forwards in the guides on the bed
plate by the screw O attached to the bed plate and working into the
rack C fixed on the bottom of the frame A. The screw is turned
as in the apparatus previously described by a double-acting ratchet D
and a double-cranked handle D¹. The apparatus, as shown, has three
cylinders G, G, G, pistons and piston rods L, L, L, and chisels or
jumpers M, M, M, at the ends of the piston rods L, L, L. Each
cylinder is provided with two trunnions carried by bearings in the frame
in which it vibrates; the outsides of these bearings are closed in to keep
the grit out of the bearings. The three cylinders are geared together
by toothed segments 9, 9, 9, 9, so that they vibrate together, and on the
centre cylinder a third toothed segment g¹ is provided, into which an
endless screw Q¹ works, it being fixed on the cam shaft Q which works
the valves. This shaft has a winch handle at the back end, and on
turning it by hand the cylinders are caused to vibrate and at the same
time motion is given to the valves by the cam P on the same shaft.
The cam, as in the apparatus previously described, is arranged to give
five strokes of the valves, and consequently five strokes of the pistons
for every revolution of the cam shaft. Stops are provided on the frame
to limit the extent of the vibration of the cylinders, and at the end of
each vibration of the cylinders the man turning the cam shaft. Q can
move the winch handle backwards and forwards a few times through
about one-tenth of a revolution before causing the machine to vibrate
•

page_text: in the opposite direction, thus working the valves without sensible
.movement of the cylinders, and so causing the chisels to make the
chases a little deeper at each end, thereby preserving their full length
in this form of apparatus as in that previously described. The valves
are of the piston description, but are in separate valve boxes O, 0, 0,
the valve rods being coupled together so that the valves may be worked
by one set of levers S, S, from one cam P. The passages in the valve
boxes leading to the cylinders are so arranged that when the top and
bottom pistons are advancing towards the rock the middle piston is
receding from the rock, so that the chisels do not all strike the rock at
once. The passages from the valve boxes are connected to the front
and back ends of the cylinders by flexible pipes N, N, to allow for the
vibration of the cylinders. The inlet pipe T to each valve box is pro-
vided with a valve or cock T¹ so as to regulate the supply of compressed
air or steam to each cylinder. The threo inlet pipes are connected to
.one general supply pipe, and the exhaust pipes U, U, U, are also con-
nected to one pipe. The cylinders G, G, G, are continued in front so as
to form guides for the piston rods, and the ends of the cotters which fix
the chisels M into the piston rods L work in slots in these guides, thus
preventing the chisels and piston rods from turning on their own axes.
India-rubber blocks are fixed in the back ends of the cylinders for the
pistons to strike against on coming back. The pistons, as in the
apparatus previously described, have a large area at the back and a
smaller annular area in the front.
To keep the machine steady while working it may be loaded at the
bottom with lead, iron, or other weights, or be stayed sideways and
upwards by tubular or telescopic stays capable of a rough adjustment by
cotters and various cotter holes, and of a fine adjustment by means of
a screw at the end.
For cutting away the rock in a large tunnel the apparatus may be
.caused to cut vertical chases or grooves at such distance apart as may
be convenient for breaking off the rock with facility by levers, or wedges,
.or otherwise, and for getting stone in a quarry the same thing may be
done, the distance between the chases or grooves being regulated at
pleasure, and in such case a few holes may be bored at the back or
bottom of the chases or grooves, and gunpowder or other explosive may
be used to bring off the blocks which have been cut in two sides in
forming the grooves.

page_text: For a shaft through stone or rock an apparatus almost exactly like
either of the foregoing forms is used, but having stays or guides with
set screws to join against the sides of the shaft to keep the apparatus
steady, its weight being suspended from above, the great advantage
being that a large amount of power can be brought to bear to work the.
chisels by means of the compressed air or steam, and thus chases or
grooves can be cut much faster than men could bore single holes, and
thus the whole of the stone or rock at the bottom may be cut all over.in
chases and grooves so near together that it may be broken away easily
by levers or wedges or other means, and no gunpowder need be employed,
so that the workmen can keep working day and night without inter-
mission, there being no occasion for them to leave the shaft for a blast
or during the time smoke would be clearing away.
The application of apparatus such as I have above described may be
best understood by referring to modes hitherto adopted for driving drift.
ways or shafts in stone or rock, and shewing wherein the action of the
above described apparatus differs therefrom, as, in order to drive such.
driftways with the greatest expedition or faster than the work can be
executed by manual labor, it is necessary to employ compressed air or
steam acting in cylinders and working chisels or jumpers with the
full force that they can bear, and giving a large number of strokes per
minute.
In some cases a number of chisels or jumpers have been attached to
one head or frame caused to reciprocate by means of a single piston
working in a cylinder. It has .however been found impossible to make
all the chisels or jumpers act with equal force on account of the
variation of hardness that occurs in the matter operated on and the
occurrence of fissures therein. Morcover when the chisels or jumpers
do not all strike fairly the inequality of blow imposes on one or more
of them the whole force delivered from the large cylinder, thus causing
fracture of one or more of the tools, or of the frame itself, and causing
others of the tools be broken by their striking the fractured pieces.
Now by actuating each of the chisels or jumpers by its own inde-
pendent piston according to my Invention each tool is worked with the
full force it is capable of bearing, and can never be subjected to greater
strain, and it is therefore not liable to be broken; also by cutting only
grooves or chases so far as is necessary to weaken the material operated
on by thus leaving portions comparatively unsupported which can be

page_text: easily removed by levers, wedges, or blasting I am enabled with a
limited power to drive a driftway with greatest expedition, having only
to cut a minimum of the material.
Having thus described the nature of my Invention, and in what
manner it is to be performed, I would have it understood that I do not
claim generally the driving of a hole in stone or rock by means of a
chisel or jumper worked by compressed air or steam, nor do I claim
the cutting of grooves or chases in stone or rock by a number of
chisels or jumpers all fastened together to a head or holder and worked
simultaneously thereby; but what I claim is,―
First. The cutting of grooves or chases in stone or rock by the action
of a series of chisels or jumpers, each worked by compressed air or steam
acting in a separate cylinder, and moved along its groove or chase, and
all advanced as the grooves or chases are deepened, substantially as
'herein described.
Second. The several constructions of apparatus for effecting the above
object, substantially as herein described.
In witness whereof, I, the said Edward Alfred Cowper, have here-
unto set my hand and seal, this Nineteenth day of December, in
the year of our Lord One thousand eight hundred and seventy-
one.