IMPROVEMENTS IN MACHINERY FOR EXCAVATING COAL AND OTHER MINERALS, AND IN APPARATUS
Year: 1869

page_text: LETTERS PATENT to Frederick Hurd, of Rochdale, in the County
of Lancaster, Engineer, for the Invention of "IMPROVEMENTS IN
MACHINERY FOR EXCAVATING COAL AND OTHER MINERALS, AND IN APPARATUS
Sealed the 7th September 1869, and dated the 25th March 1869.
PROVISIONAL SPECIFICATION left by the said Frederick Hurd at
the Office of the Commissioners of Patents, with his Petition, on
the 25th March 1869.
I, FREDERICK HURD, of Rochdale, in the County of Lancaster,
Engineer, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN MACHINERY FOR EXCAVATING COAL AND OTHER MINERALE,
AND IN APPARATUS FOR COMPRESSING AIR FOR DRIVING THE SAME, AND FOR OTHER
PURPOSE," he as follows:

page_text: of a series of link stocks containing the cutters, which are jointed
together in such a manner that no rivets or connecting pins are required;
this series of cutters passes around a pulley mounted in a radial arm,
and around a toothed wheel fixed to a shaft which fits in a telescope
frame, to increase or reduce its length; the radial arm is provided with
grooves which support the back of the cutter stocks, and prevent them
from being drawn out of the groove in the radial arm. This toothed
wheel is driven to give motion to the cutters by my improved motive
power engine hereafter described, or in any other convenient manner.
The position of the radial arm is changed so as to give the required cut
by a worm fixed to the outer shell of the telescope shaft, and a cam
fixed to the driving wheel; this cam by a lever and catch turns the
worm at intervals; and thus advances the cutters to the extent required.
The engine consists of an oscillating cylinder to which the compressed
air or other elastic fluid is admitted, and from which it is exhausted
through two or more ports, the oscillation of the cylinder causing the
ports to be opened and closed at the proper times without the aid of
eccentrics or valves for giving the requisite to-and-fro motion to the
piston, which is connected to the crank pin in the fly wheel. The
engine can be reversed by two double taps placed in the passages
leading to and from the ports, which taps are connected and worked
simultaneously by levers or gearing. The cutting apparatus and the
engine by which it is driven are connected to a bracket which fits on a
screwed pillar, and it is raised or lowered by gearing connected to the
engine, and which gearing reverses the direction of motion up or down
by changing the position of the wheels. The bracket also supports
two shafts with two eccentrics for acting on surface clips, one to secure
the bracket in the position required and the other to secure the radial
arm.
When compressed air is used for producing the motive power I
charge a receiver or a set of pipes with the air compressed by a
stationary engine, or the fall of the water in the pit, and convey this
receiver or set of pipes to the engine for giving motion to the excavating
machinery, thereby saving the pipes required for connecting the air
pumping engine with the excavating machine as now customary.
The apparatus for compressing air consists of a series of pump barrels
the pistons of which are worked by a diagonal disc or other equivalent,
this disc is driven by steam or other power, and the pump barrels are
all united to the air receiver. As the pressure increases in the receiver

page_text: the piston rods are disconnected in succession from the driving disc
until the final compression is obtained by the last pump barrel.
pumping apparatus is placed in a water course to keep the barrels cool.
The
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Frederick Hurd in the Great Seal Patent Office
on the 24th September 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FREDERICK
HURD, of Rochdale, in the County of Lancaster, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the. Twenty-fifth day of March, in the year
of our Lord One thousand eight hundred and sixty-nine, in the thirty-
second year of Her reign, did, for Herself, Her heirs and succes-
sors, give and grant unto me, the said Frederick Hurd, Her special
license that I, the said Frederick Hurd, my executors, administrators,
and assigns, or such others as I, the said Frederick Hurd, 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 EXCAVATING COAL AND OTHER MINERALS, AND IN APPARATUS
TOR COMPRESSING AIR FOB DRIVING THE SAME, AND FOR OTHER PURPOSES,"
upon the condition (amongst others) that I, the said Frederick Hurd,
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 Frederick Hurd, 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 (that is to say) :-
My Invention consists in cutting horizontal, longitudinal, radial, and

page_text: diagonal grooves in the coal or other mineral to be excavated, by means
of a series of link stocks containing the cutters which are jointed
together in such a manner that no rivets or connecting pins are required;
this series of cutters passes around a pulley mounted in a radial arm, and
around a toothed wheel fixed to a shaft which fits in a telescope frame,
to increase or reduce its length; the radial arm is provided with grooves
which support the back of the cutter stocks and prevent them from being
drawn out of the groove in the radial arm. The toothed wheel is driven
to give motion to the cutters bymy improved motive power engine hereafter
described, or in any other convenient manner. The position of the
radial arm is changed so as to give the required cut by a worm fixed
to the outer shell of the telescope shaft, and a cam fixed to the driving
wheel; this cam by a lever and catch turns the worm at intervals, and
thus advances the cutters to the extent required. The engine consists
of an oscillating cylinder to which the compressed air or other elastic
fluid is admitted, and from which it is exhausted through two or more
ports, the oscillation of the cylinder causing the ports to be opened and
closed at the proper times without the aid of eccentrics or valves for
giving the requisite to-and-fro motion to the piston and piston rod, which
latter is connected to the crank pin in the fly wheel. The engine can be
reversed by two double taps placed in the passages leading to and from
the ports, which taps are connected and worked simultaneously by levers
or gearing. The cutting apparatus and the engine by which it is driven
are connected to a bracket which fits on a screwed pillar, and it is raised
or lowered by gearing connected to the engine, and which gearing
reverses the direction of motion up or down by changing the position of
the wheels. The bracket also supports two shafts with two eccentrics
for acting on surface clips, one to secure the bracket in the position
required and the other to secure the radial arm. When compressed air
is used for producing the motive power I charge a receiver or a set of
pipes with the air compressed by a stationary engine, or by the fall of
the water in the pit, and this receiver or set of pipes is conveyed to the
engine for giving motion to the excavating machinery, thereby saving
the pipes required for connecting the air pumping engine with the
excavating machine as now customary.
The apparatus for compressing air consists of a series of pump barrels
the pistons of which are worked by a diagonal disc or other equivalent,
this disc or its equivalent is driven by steam or other power, and the
pump barrels are all united to the air receiver. As the pressure increases

page_text: in the receiver the piston rods are disconnected in succession from the
driving disc or its equivalent until the final compression is obtained by
the last pump barrel. The pumping apparatus is placed in a water
course to keep the barrels cool.
Having now described the nature of my Invention, I will proceed to
describe the accompanying 6 Sheets of Drawings, reference being had to
the figures and letters marked thereon.
On Sheet 1, Figure 1 is a plan of my improved machinery for exca-
vating coal and other minerals, and Figure 2 is an elevation of the same.
On Sheet 2, Fig. 3 is a section of the telescope shaft, and Figs. 4, 5,
6, and 7 are detached views of the oscillating cylinder and the register
plate valve.
a is the bracket or frame of the machine to which the oscillating
cylinder b and other parts are connected. The piston in the cylinder b
is operated by compressed air, steam, or other elastic fluid, the piston
rod is connected to a pin in the face of the fly wheel c, keyed to the
shaft c'; to the inner face of the wheel c is cast a skewed bevel wheel c³,
which gears into and drives the skewed bevel pinion c* on the stud c
screwed into the bracket a. To the end of the shaft c' is keyed a bevel
pinion d which gears into a wheel d', which drives the link stocks
containing the cutters by means of the star wheel e³, shewn in Figs. 16
and 17. The bevel wheel d' has a long boss connected to the shaft e by
a key and groove.
Under the bevel wheel d', shewn best in Fig. 3, or
between it and the casing j, is a cam for giving a reciprocating motion
to the link f jointed to the lever f', to which is jointed a spring pawl or
catch, which drives the pinion g! keyed to the shaft g. The shaft g
has a worm on it for working into the worm wheel c cast to the outer
sleeve e of the shaft e, thus giving an advancing motion to the cutter
On the stud c³ is a small spur wheel h. cast with the bevel
pinion c. The swing lever h carries an intermediate wheel, for con-
necting the wheel h to the wheel h³ screwed on the screw pillar i. The
spur wheel h³ is held between the lever h' and the bracket a, thus forming
a nut on the screw i, by which the machine may be raised or lowered on
the pillar by the engine. The lock lever h' is for holding the lever h
when the wheels are either in or out of gear. On one side of the
screw there is a friction clip k¹, shewn in Figs. 1 and 3 placed loose in
the bracket a; this clip is brought into contact with the screw i by the
eccentric shaft k for the purpose of securing the machine on the screw
arm e

page_text: pillar while at work. When it is required to alter the position of the
machine on the pillar the eccentric shaft may be disengaged from
the friction clip k' by turning the eccentric shaft partially round, and
the swing lever h' may then be movedi so as to bring the wheels h
and into gear; the machine may be raised or lowered on the pillar
by reversing the engine. The box or frame j, see Fig. 3, has cast on
it a long boss which forms the bearing for the shaft c¹, and projects
into the bracket a. In order to secure the box j I make use of the
eccentric shaft l, which works against the clip. l, shewn in Figs. 1
and 3, holding it firmly against the boss of the box or frame j. By
turning the eccentric shaft and loosening the clip the frame j with
the cutter arm may be made to describe a circle on the shaft c' as a
centre. A collar is cast on the boss of the frame j, against which the
friction clip acts to hold the frame j against the face of the bracket a.
The eccentric shaft may act on a loose key which holds the clip "
against the collar on the bracket j to prevent it from being drawn
from the bracket a when the eccentric shaft is disengaged. The
traversing cutter arm e' is driven as follows:-The bevel pinion d on
the shaft c¹ gears into the 'wheel d¹; this wheel d' has a long boss
through which the shaft o may be moved; a key is fastened to the
interior of the wheel d¹ with a groove or key way in the shaft e; the
boss of the bevel wheel d' revolves loosely in the sleeve e¹; to this
sleeve e' is bolted the arm or frame e' around which the cutters e³ travel;
the sleeve e¹ is secured to the outer case e by the nut e, as shewn in
Figs. 1 and 2; on the outer case of at its lower end is cast a worm
wheel actuated by the worm on the shaft g; by this means the outer
case and the sleeve e' carrying the cutter arm e* and cutters which are
made to revolve, thus advancing the cutter arm to its work. The worm
wheelcast to the case es is held in the box j. By loosening the nut e
the sleeve e¹ and with it the cutter arm e and the shaft e may be drawn
in or out through the casing e and secured in any position by the nut e.
The parts above described marked d¹, e, e¹, and e form the telescope
shaft. By moving the handle n', see Fig. 3, the bevel wheel d¹ is drawn
out of gear with the bevel pinion d, thus stopping the cutters instantly
without stopping the engine. The box or frame j is capable of a rotary
motion on the face of the bracket a for altering the angle of the cut
made by the cutters. The bevel wheel d' is keyed to the shaft e by a
sliding key; the grooved. cam d is fastened by screws to the bevel
wheel d'; the washer dis attached to the end of the short shaft n

page_text: and is screwed to the eccentric d³ and the wheel d', thus connecting
them to the shaft n. The handle n' is secured to the lower end of the
shaft n.
On the shaft n are two bushes m and m¹, which fit in the
boss of the frame j; a diagonal slot is cut in the upper bush m, into
which a pin m³ fastened into the shaft n enters; the two adjacent ends
of these bushes are cut off diagonally, and slide against one another
when the shaft n is turned by the handle n', or otherwise. The operation
is as follows:-When the machine is at work, that is to say, when the
bevel wheel d' is being driven by the pinion d, the parts occupy the
position shewn in Figure 3. In order to draw the wheel d' out of gear
with the pinion d, the handle n¹ must be turned one quarter round, thus
turning the shaft n and the bush m' which is fastened to it; the upper
bush m, having a groove in it is drawn by the pin in the shaft downwards
and with it the bevel wheel d' and the eccentric &, thus releasing the
connection between the wheels d and d'; the upper bush m is guided by
pins or screws passing through the boss j, the points of which enter into
vertical grooves in the bush m to prevent it revolving. By this arrange-
ment the requisite up-and-down motion is insured. The feed motion is
thus always stopped unless the cutter arm e' and shaft e are in motion.
The shaft is hollow, and to its lower end is connected a pipe n³, which
conducts water through it and upwards through the hollow shaft e, and
by channels in the star or toothed wheel e against the stocks e con-
taining the cutters e³, for the purpose of cleaning and keeping them
cool. The pillar screw i is composed of several pieces screwing into one
another that the length may be altered according to the height of the
working; into the top piece of the pillar screw a smaller screw works,
as shewn in Sheet 3, Fig. S, which represents a perspective view of the
machine. To the upper end of this smaller screw is connected by a ball-
and-socket joint, shewn in Sheet 4, a loose clamp ¹, by which the
pillar i may be wedged fast in the working. The lower part of the
screw fits into a frame shewn best in Fig. 2 supported on wheels
for moving the machine along the mine.
Figs. 4, 5, 6, and 7 on Sheet 2 represent my improved oscillating
cylinder and reversing motion previously referred to. b is the cylinder:
b', the valve face of the cylinder b. The face b' is provided with six
ports, three on the upper half of the face b', lettered 6, and three on
the lower half of the face b', lettered 6; the upper ports open into
the passager, and the lower ports 6 open into the corresponding

page_text: passage s; the passages rands are distinct and separated by a feather
cast with the cylinder. The taper plugs t and u are each provided with
two passages opening into the chambers 7 and 8, seen in Fig. 4; the top
and bottom passages in each plug t and u are at right angles to each
other. The Drawing shews the lower passage in the plug t open; the
upper passage of the plug u is also open so long as the lower passage in
the plug t remains open. The taper plugs t and u are connected by the
levers and ' and link v³, see Fig. 5 and Fig. 1.
By moving the
handle the passages of the taper plugs t and u are reversed, thus
reversing the direction of the engine. The boss z, Fig. 5, fits into a
recess in the bracket'a, through which the valve stem 6* passes, and the
valve faces are held together by the springs 65 shewn in Fig..1. Figs. 6
and 7 represent the stationary valve face on the bracket a with the
admission and exhaust ports. a is part of the bracket of the machine;
w is the pipe for admitting compressed air or other fluid to the engine;
are the feed ports, and y the exhaust ports. When compressed air is
used the exhaust requires no pipe to convey it from the engine; with
steam one must be used.
To the right of Fig. S is shewn a vertical face of coal with two
horizontal slots or cuts made by the machine near the top of the work-
ing. After removing the coal from-between these cuts a cut can be
made by the machine at right angles to them as shewn.
Figures 9 and 10 represent an application of this machine by which
circular shafts may be sunk. The machine is secured to the lower side
of the frame o. This frame is somewhat smaller in diameter than the
shaft, and of sufficient size to allow a man to work in it. The Drawing
represents several angular cuts at the bottom of the shaft; the coal or
other mineral is removed by the man in the frame o, and the machine.
which is similar to that shewn in Figs. 1, 2, and 3 is adjustable in the
same manner. In this case the pillar i is in a horizontal position. The
frame o is held by the holders o' which are forced by the weight of
the machine and frame into the sides of the shaft; these holders o' can
be disengaged by the operative when it is desired to lower or raise the
machine.
Fig. 11 represents the machine at work in a coal mine, the pillar i
being braced against the top and bottom of the working, the operator
can readily alter and set the frame j and cutter arm e' to any angle, as
before described.

page_text: Figs. 12 and 13 are an elevation and plan of a modification of my
improved excavating machinery particularly adapted for getting coal in
very narrow seams. This machine is fully described in Sheets 4 and 5..
Figure 14 on Sheet 4 represents an elevation, and Figure 15 on
Sheet 5 is a plan of a machine for getting coal by means of horizontal
cuts made on the bottom of the seam. a is the frame of the machine to
which the oscillating cylinder b is fastened; the piston rod is connected
to a pin in the face of the fly-wheel c. The cross head is supported by
guides fastened to the face of the cylinder. The wheel c is keyed to the
shaft c', which has on it a spur wheel d gearing into and driving a
wheel d' on the shaft e, to which the star wheel e for driving the cutter
stocks e is fastened. This star wheel is shewn detached in Figs. 16
and 17, on referring to which it will be seen that the teeth of the star
wheel are hooked, thereby catching hold of the cutter stocks and pre-
venting them being pressed from them. The cutter stocks are linked
together as shewn in Fig. 15 without the aid of rivets or connecting
pins, and they pass around a plain pulley at the end of the cutter
arm, the position of which is regulated by a screw and lock nut so
as to take up the slack of the endless cutters. To the shaft e below
the wheel d is keyed a segment of a worm gear f which gears into and
receives motion from a worm g' on the shaft g. The pawl or catch h on
the lever receives a reciprocating motion from a grooved cam cut
in the lower face of the spur wheel d', a pin in the end of the lever h³
runs in this groove, thus giving an oscillating motion to the lever h² on
the fulcrum h³; the lever his connected to the lever h¹, and as the
pawl moves it advances the wheel g³ on the shaft g, and the worm g'
gearing into the segment of a wheel turns the shaft e, thus advancing
the cutter arm to its work. The pillars i are supported at the bottom in
the frame j, and pass upwards to the roof through worm wheels p' in
the frames p; the shaft k extends across the machine, and on it are cut
the worms k¹. To the ends of the shaft are handles k for the purpose
of raising or lowering the bracket a and cutter arm e. The shaft k
passes through the hollow shaft q which carries the bracket a with the.
cylinder and cutter arm e*: This hollow shaft is secured in bearings in
the frames p by the screws p. The eccentric shaft m is for the purpose
of locking the friction clip against the hollow shaft q to secure the
bracket a and cutter arm e* at any angle to suit the rise or fall of the
floor of the mine. The machine is held in position in the seam by the

page_text: two clamps ¹, which are connected to the pillars i, as before referred to;
w is a pipe for admitting compressed air, steam, or other elastic fluid to
the cylinder b; n' is the exhaust pipe if steam or water is used. The
frame j is supported on three wheels for facilitating the moving of the
machine in the mine or seam. The wheels are connected to the frame
by swivel studs to allow them to twist in any direction.
Figs. 18, 19, and 20 on Sheet 4 are three views of a cutter arm con-
structed according to a modification of my Invention. In Fig. 18 the
sides of the cutter arm are shewn parallel instead of being slightly
curved, as shewn in Figs. 13 and 15, and the grooves in which the link
stocks travel are made with recesses into which projections from the
link stocks enter to prevent them being drawn out of the groove during
the cutting.
On Sheet 6, Figure 21 is an elevation, and Figure 22 an edge view of
my improved machinery for compressing air. A is a shaft on which as
many cranks are formed as there are pumps to be driven; the shaft A
revolves in bearings in the frames B to which the pump barrels C are
attached. These pump barrels are made by preference of different
diameters. The pistons of the pump barrels are fixed to the piston
rods D. These piston rods are provided with cross heads E working in
slides formed by the frame B and the bracket B'. In the vertical slot of
the bracket B' is fitted the slide F, which is raised and lowered in the
slot by the screw G and hand wheel H, or the mechanism for working
the screws G may be connected to a governor. To the projecting arm of
the slide F is suspended the radial slotted lever I, to the lower end of
which is jointed one end of the connecting link J, the other end of which
is jointed to the crank shaft A, consequently as the shaft revolves the
lever I vibrates on its fulcrum stud I' fitting in the slide F.
The pump.
barrels C are all united to an air receiver, and the air is admitted to and
discharged from the pump barrels through balanced valves of the
ordinary description. When the slide F is in the position shewn in the
Drawing the fulcrum stud of the lever I coincides with the stud through
the cross head E, consequently when the crank shaft revolves no motion
is given to the piston in the pump barrel, but when the slide is up, as
shewn by dotted lines in Figure 21, the crank shaft in revolving gives
the full traverse to and fro to the piston, and by varying the position of
the slide the length of the traverse can be regulated to any extent-
between these two points.

page_text: The mode of operation is as follows:-When the machine is started
all the slides F are at the top of the slots in the brackets B' so as to
impart the greatest traverse, to the pistons in the pump barrels, but as
the pressure increases in the receiver the slides are lowered to reduce the
length of traverse either by hand or by the governor, and they are
brought in succession to the lowest point where, as before stated, the
pistons cease to be actuated by the cranks, consequently the final com-
pression may be obtained by the smallest force pump. By this arrange-
ment very high pressure can be obtained with comparatively little
power. I wish to observe that in some cases the air pumping machinery.
may be worked by the fall of the water in the pit, and that a diagonal
disc or eccentrics may be used instead of cranks, as shewn.
The apparatus for compressing air may be employed to charge a
stationary receiver, or a portable set of pipes forming a receiver. These
portable pipes or receiver may contain sufficient compressed air to work
the excavator from one to two hours, and they may be placed in the
working so as not to interfere with the traffic of the mine, thereby saving
the pipes required for connecting the air pumping engine with the
excavating machine as now customary.
Having thus stated the nature of my Invention, and described the
manner of performing the same, I declare that I claim as my Inven-
tion:-
First. The general combinations and arrangements of the machinery
for excavating coal and other minerals as shewn and described.
Secondly. The mode of securing the excavating machinery to the
screwed pillar i, as shewn and described.
Thirdly. The mode of varying the angle of the cutter arm e', as shewn
and described.
Fourthly. The modes of constructing the cutter arms e, as shewn and
lescribed.
Fifthly. The modes of constructing the cutter stocks e so as to form
an endles cutter of any required length, as shown and described.
Sixthly. The improved register plate valve for admitting compressed
air, steam, or other fluid to an oscillating cylinder, as shewn and
described.
Seventhly. The application of the taps t and u for reversing the
engine, as shewn and described.

page_text: Eighthly. The application of a telescope shaft to excavating machines,
as shewn and described.
Ninthly. The application of a jet of water for cooling and cleaning the
cutters, as shewn and described.
Tenthly. Supporting the pillar frame of excavating machines on rollers
mounted in swivel studs, as shewn and described.
Eleventhly. The improved arrangement of machinery for compressing
air and the mode of arresting the action of the force pumps as the
pressure increases, as shewn and described.
And, twelfthly. Supplying compressed air for working excavating
and other machines by portable receivers, for the purposes described.
In witness whereof, I, the said Frederick Hurd; have hereto set
my hand and seal, this Twenty-third day of September, One
thousand eight hundred and sixty-nine.
Signed in the presence of
EDWIN PILLING.
FREDERICK HURD. (L.S.)