IMPROVEMENTS IN MINING, TUNNELING, AND STONE-DRESSING MACHINES, AND VALVE MOTION THEREPOR
Year: 1867

page_text: LETTERS PATENT to William Snell, of No. 16, Clement's Inn, Strand, in
the County of Middlesex, for the Invention of "IMPROVEMENTS IN
MINING, TUNNELING, AND STONE-DRESSING MACHINES, AND VALVE MOTION
THEREPOR." A communication from abroad by Richard Channing More
Lovell, of Covington, in the County of Kenton, and the State of
Kentucky, in the United States of America.
-
Sealed the 9th August 1867, and dated the 27th May 1867.
COMPLETE SPECIFICATION filed by the said William Snell at the Office
of the Commissioners of Patents, with his Petition and Declaration,
on the 27th May 1867, pursuant to the 9th Section of the Patent Law
Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
SNELL, of No. 16, Clement's Inn, Strand, in the County of Middlesex, send
greeting.
WHEREAS I am in possession of an Invention for "IMPROVEMENTS
IN MINING, TUNNELING, AND STONE-DRESSING MACHINES, AND VALVE MOTION
THEREFOR," 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 the same is a communication to me from

page_text: abroad by Richard Channing More Lovell, of Covington, in the County of
Kenton, and the State of Kentucky, in the United States of America.
NOW KNOW YE, that I, the said William Snell, do hereby declare that
the following Complete Specification, under my hand and seal, 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 making a part of this Specification.
Similar letters of reference in the Drawings indicate corresponding parts.
Figure 1 is a top view or plan; Figure 2 is a side elevation; Figure 3 is
a plan of the traverse track and platform; Figure 4 is a vertical longitudinal
section of the same on the line x, x, Figure 3; Figure 5 is a vertical longi-
tudinal section on the line y, y, Fig. 1; Figure 6 is a vertical longitudinal
section on the line z, z, Fig. 1.; Figure 7 is a vertical transverse section on
the line w, w, Fig. 1, looking in the direction of the arrow w¹; Figure 8 is a
vertical longitudinal section on the line r, r, Fig. 1, looking in the direction
of the arrow ; Figure 9 is a vertical section transversely to the cylinders
and longitudinally of the valve chambers and valve operating piston chamber
on the line w, w, Fig. 10; Figure 10 is a vertical section on. the line a, a,
Fig. 9; Figure 11 is a horizontal section on the line y, y; Fig. 9; Figure 12
is a horizontal section on the liné z; z, Fig. 9; Figure 18 is a plan view of a
modified form of the platform, shewing a larger opening to allow the unshipping
of the cog wheel from the rack on the tramway.
A track for the traversing platform is laid down parallel with the upright_
face of the coal, '&c.; the forward adjustment of the machine on its platform
is made after each traversing cut. The chisels are operated alternately by
their respective engines, the leading chisel cutting half the depth and the
following one completing the cut, the chisels being reversed and changed in.
cutting back. The motor is either steam or compressed air, conducted to the
engine by pipes from the 'exterior of the shaft or drift. Momentuin is given
to the stroke of the chisels by loading the pistons, and the return motion is
given to each piston by the effective stroke of the other piston; to which it is
connected by a working beam. The steam is changed as the piston passes a
certain point in the cylinder by the admission of the live steam to an auxiliary
cylinder whose piston works the valve. The valve arrangement is adapted 'to
the use of two single-acting engines; it consists of a balanced valve operated by
a double-acting piston in a cylinder to which steam is admitted from the
engine cylinders alternately. The motion of the working beam which connects
the ends of the pitman actuates a rock shaft, ratchet, and shaft, whose piniou

page_text: gears into the rack on the traverse track; the same shaft has a thread, with
which a clutch nut of the traverse platform is made to engage for the forward
and backward motions of the machine, a pawl on the latter engaging with a
rack on the platform to keep the. machine in position.
In the Drawings A, A, are the tracks, and A' a central rack bar, which are
laid down parallel with the upright face of the coal, stone, or other material
which is being quarried or the stone which is being dressed; this is intended
to be laid in sections collectively as long as the length of the breast of coal
which is being miued, and the machine works automatically from one end to
the other of this track, being reversed by hand and returning after reaching
the indicated distance.
Figure 3 represents another arrangement of the track which is curved; in
this case the track B, B, and rack bar B' are ares of a circle whose.centre.is
the pivotal point C of the traverse platform D; this form is specially intended
for "driving in" to the bank, making a "drift" or "gallery."
Figure 4 shows this latter arrangement in section, the traverse platform D
being connected by the bar d to the pintal C, and having on. its upper edge
the rack bar d', by which the machine is held in position by the pawl di ant
catch d, as shown in the elevation, Fig. 2; these portions are lifted out of
engagement when the engine is to be moved forward or back,, which motion,is
to be effected by means to be described.
I have spoken of the traverse track A, A, A¹, or B, B, B', which differ in
respect of the,curve of the latter, and I have also referred to the traverse
platform D which follows.the track on which it is placed; in the former, the
motion of the platform is rectilinear, and in the latter it is in a curve; in
each it is reciprocating by the engagement of the spur wheel E on the shaft.e.
underneath the carriage E¹ of the machine with the rack bar A¹ or B¹, as
the case may be.
In Figure 13 is shown a convenient arrangement, whereby the cog wheel E
of the carriage may be unshipped at pleasure from the track bar A¹ or B¹,
as the case may be. To accomplish this I increase the width of the opening
in the traverse platform, through which the driving cog wheel works, so
as to allow the cog wheel to be thrown out of gear on either side of the
stationary cogs attached to the tramways underneath; on the underside of
the platform is a plate, which is moved by the levers pivoted underneath the
platform and connected to, the plates by links or rods. For the sake of
convenience the levers are not allowed to project far beyond the edges of the
platforms, and are moved by a handspike which enters the lever socket,.as

page_text: seen in Fig. 8, where a corner of the platform is broken off to exhibit
this feature; the motion of the levers on their pivots slips the plate, which
carries with it the cog wheel, either to withdraw from engagement with the
rack or restore it thereto, as the case may be. The construction and arrange-
ment of the shaft.e is perhaps better shown in Fig. 6 than elsewhere, from
which it will be seen that it has bearings at e¹, e, at the respective ends of the
carriage E. The cog wheel E revolves with the shaft e, but slips thereon,
being. secured by a spline to the shaft.
'
I propose to describe the motions of the engines presently, but as the
traverse motion of the machine is automatic and depends upon the motions
of the pistons I shall assume the latter for the present, and state that the
working beam F receives a rotary reciprocating or vibratory motion therefrom.
The edge of the working beam F towards the engines has an extension
beneath, to which is secured a yoke d, which rocks the arms d¹ (see Figs. 7
and 8), and rotates the cog wheel d", which is fastened to the shaft.e. The
rotation is performed by the intervention of one or the other of the pawls a, a',
throwing one pawl into gear with the cng wheel d", rotates the shafte in
one direction and the other pawl contrariwise, and this control of the pawls is
obtained by the pendulous latch 6, whose motions in one or the other direction
raise the respective pawls, or, as in Fig. 8, by occupying a vertical position
hold them both out of engagement with the wheel, and permit the shaft e to be
turned by the hand crank b' to shift the machine as they traverse iude
pendently of the motions of the engine. It is intended that the traverse
motion of the machine shall be automatic, driving the chisels into the breast
of the coal, for instance, to a given depth, making a horizontal continuous
tissure; as soon as it reaches the end of the track, or sooner if required, the
action of the machine is stopped; the chisels are now changed and reversed
ready for the return traverse, the necessity for and mode of doing which will
be presently explained. For the purpose of taking another chip a forward
motion of the machine towards the bank is required, and this is effected by
raising the lever G and half nut g, so as to engage with the thread on the
shaft.e. The revolution of the shaft by the hand crank 6 will now give the
required longitudinal motion to the machine out or in, the latter being towards
the coal and to the right extent, say, for instance, two inches; the pawls u
and a¹ are reversed so as to change the direction of traverse of the platform,
and the machine commences its return motion, the pawl and latch d
d, keeping it in place, and the nut a lowered so that the revolution of
the shaft. e, which is necessary to rotate the traversing pinion E, shall not

page_text: affect the longitudinal position of the machine as the screw g¹ revolves. An
oblique approach of the chisel to its work or recession from it may be obtained
by allowing the wheel E to rotate simultaneously with the engagement of the
thread g with the clutch nut g, the longitudinal and traverse motions being
concurrent and the motion. being compound, the resultant of the combined
forces. The cylinders H, H¹, are single acting and are operated by the
pressure of compressed air or of steam conducted into the mine by pipes, and
immediately connected to the induction of the valve chamber of the engine
by a flexible pipe. In each cylinder is a piston rod I loaded or weighted by
a piston block; and passing through a stuffing box at each end of the
cylinder, each piston is provided at one end with a chisel and at the other end
with a cross head, which moves in or on slides, the pitman J connecting the
respective pistons to the working beam F, which has been already referred to
as moving the arm d². The motions of the valve in the chamber K are made
by means of the steam from the working cylinders acting upon a piston in
the smaller cylinder L; K is the packing ring of the piston block, and on the
upper edge of the latter is a groove which communicates with the space in the
cylinder at the rear of the piston. As soon as the packing ring K
passes the
port m the live steam in the cylinder passes through the groove in the piston
through port m, and by the steam passage to the smaller cylinder L, where it
acts upon one side of the small piston T and actuates the valve S in chamber K
the other side of the piston T is only exposed to the pressure of exhaust steam
which yields and escapes through port m to the other cylinder which is iu
communication with the exit pipe. The valve in chamber K and the piston
in cylinder L are connected by a rod the handle of which affords means of
manipulation to change or reverse the steam. Each piston is single acting,
steam being admitted and exhausted through the passage R which connects
th end of the cylinder with the valve chamber Ķ, the connection of the
cylinders H, H, being made with chamber K at p, p, respectively. Live
steam is admitted from the boiler to each end of the balance valve S, while
the space included between the valve heads is occupied by exhaust steam
which finds the exit at the pipe W; steam is supplied to the valve chamber
by pipe X, and the induction opening is controlled by the throttle valve M.
At the lower side of each cylinder H, H, and near the front end, is an
opening n which admits air to and from the cylinder in front of the piston.
The latter are single acting, and the air is permitted free exit to and from in.
front, until the front end of the piston has passed the port n, when the
'remaining air is compressed between the piston and the front of the cylinder,

page_text: cushioning the piston to some extent, though this latter effect is principally
obtained by the admission of live steam behind the other piston, the two. being
connected by the working beam F, as has been stated.
The mode of operation has been stated incidentally as to each part in stating
Itheir construction and relation, but it may be briefly summed up so as to assist
the understanding of the connection.
The track A, A, A, or B, B, B', as the case may be, is laid down and
leveled so as to get it "out of wind," that is, in a true plane; upon this
depends the correct working of the machine, which is then mounted thereon,
and the steam connection made. The chisels have each a cutting face and a
rear, slope, and one is shorter than the other, the one working in advance being
the shorter of the two, and the straight edge being presented. If the chip to
be cut during the single traverse be two inches, the machine will be advanced
on the platform to such an extent that the forward chisel will have a cutting
depth of one inch, and the rear chisel an additional inch, so that their duty is
equal; and I may here state that when the machine has arrived at the end of
its traverse, and before it starts back, the chisels are taken out and changed
as well as transposed in position, so that the short chisel is shifted into the
advance, and the cutting faces properly presented. The position of the machine
on its platform being secured by the pawl and latch d, d, the steam is
admitted, and the chisels commence their reciprocating motion, chipping away
the coal or other matter to which they are applied, the machine traversing
,horizontally by the motion of the shaft e and wheel E on the rack bar beneath,
as have been already described. The end of the traverse being reached, the
chisels are stopped, changed, and reversed, and the machine advanced on its
platform for another cut; the pawls a, a, are then adjusted for the reverse
motion of the shaft e, and the steam being admitted the machine returns upon
its track. The carriage is represented as mounted on wheels upon the track,
.but slides. may be substituted..
In the dressing of stone the machine may work automatically along the face
of the stone, or the table of the machine. may be made stationary, and the
stone be made to move automatically on a carriage mounted on a rail or
tramways in front of the chisels, or both may be made to move according to
the nature of the work to be performed, chisels of such form being used as
are adapted to the nature of the material or the progress of the work.
In mining or tunneling, when the machine has been moved forward on its
platform to the extent of its range, and it is desired to give the chisels a further
penetration, the machine is backed out, and longer chisels inserted in the

page_text: chisel sockets; the work is then resumed, and thus. the required depth attained.
The depth attained by a given traverse across the face of the matter
under. treatment will vary according to its hardness and intractability; with
coal a penetration of two inches divided between the two chisels may be
attained, and probably considerably more; with stone it would be less than
with coal, but would vary according to the quality of stone.
In stone dressing the character and edge of the tool will be made conformable
with its duty; it may be a pointed pick, an edge chisel, or of a gouge shape,
with the required outline of cutting face for cutting flutes in columns or with
faces adapted to pound and dress the surface after the more decided chipping
is finished. While I do not confine myself to any particular scale or proportions
I will indicate what I at present propose to use for a given kind of work, and
1 do not wish that my data should be taken as conclusive on the subject. The
machine represented in the Drawings is intended for mining coal, the scale
being one inch to the foot, half the cylinder approximately being occupied by
the piston block, whose weight gives effectiveness to the stroke of the chisel.
The loaded piston acts as a hammer, and the power of the stroke being greatly
due to the weight of the piston, the reaction of the blow is received thereon,
relieving the machinery of considerable jar and strain.
Having described my Invention, what I claim as new and desire to secure
by Letters Patent is,―
First, I claim the combination of the traverse track, the traverse platform,
and the adjustable carriage on which the engine is mounted, substantially as
described.
Secondly, I claim the combination of the two pistons, the piston rods
furnished or to be furnished with chisels, and the working beam to which they
are connected, and by which their alternation is secured.
Thirdly, a mining or stone cutting machine adjustable longitudinally and
laterally by means substantially as described, and having two cylinders whose
piston rods are connected to a working beam.
Fourthly, I claim in combination with the carriage E¹, upon which the
engine is mounted, the shaft e, the splined wheel E, cogged rail A¹ or B³, and
rotating devices d", a, d¹, a¹, or their equivalents, deriving their intermittent
motion from the reciprocating motions of the working beam, or its motors the
pistons.
Fifthly, I claim the combination of the traverse platform D, the carriage E¹,
the threaded shaft g', e, and clutch nut 9, operating substantially as described.
Sixthly, I claim the combination of the carriage E¹ with its rack bar d' on

page_text: the traverse platform, the pawl d and latch du constructed and operated
substantially as described.
Seventhly, the arrangement of the piston i, i, ports m, m, and double-acting
valve moving pistons T, substantially as described.
In witness whereof, I, the said William Snell, have hereunto set my
hand and seal, this "Twenty-fifth day of May, in the year of our Lord
One thousand eight hundred and sixty-seven.