IMPROVEMENTS IN COAL MINING AND ROCK DRILLING MACHINES
Year: 1879

page_text: LETTERS PATENT to Benjamin Joseph Barnard Mills, of the Firm of Harris
and Mills, of 23, Southampton Buildings, in the County of Middlesex, Patent
Agent, for the Invention of "IMPROVEMENTS IN COAL MINING AND ROCK
DRILLING MACHINES." A communication from abroad by Jonathan Washing-
ton Harrison, Miller, and Orange Butler, Merchant, both of Wayne, in the
State of Michigan United States of America.
PROVISIONAL SPECIFICATION left by the said Benjamin Joseph Barnard
Mills at the Office of the Commissioners of Patents on the 6th February
1879.
BENJAMIN JOSEPH BARNARD MILLS, of the Firm of Harris and Mills, of 23,
" IMPROVE-.
Southampton Buildings, in the County of Middlesex, Patent Agent.
A communication from
MENTS IN COAL MINING AND ROCK DRILLING MACHINES.”
abroad by Jonathan Washington Harrison, Miller, and Orange Butler, Merchant,
both of Wayne, in the State of Michigan, United States of America.
The improved machine is constructed with a drill or pick of peculiar construction
having a concave face or end and thin concave edges. A longitudinal reciprocating
motion is imparted to this drill by means of a piston working in a horizontal
cylinder, and driven by compressed air or steam, which is admitted to the ends of
the cylinder alternately by means of either a rotary or reciprocating valve, driven
by a double rotary engine consisting of a pair of eccentrics coupled together, so as
to stop and start at any point and governed by two slide valves held down by air
or steam pressure, as is usual with steam engine valves. The motion of the
machine is regulated by a throttle operated by a lever on the end of the valve
chest. A hand wheel is mounted on the shaft of the coupled eccentrics for starting
them. In each end of the cylinder is a rubber cushion, that in the forward end
through which the piston rod carrying the pick works being annular and fitting
over a nose projecting inward from the cylinder head, and screw-threaded to secure
the rubber cushion, the front face of the piston being recessed to receive said nose.
The inner portion of the piston rod may be round, but the outer part is of square,
octagon, or other non circular shape, and works through a guiding sleeve fitted to
rotate on the front cylinder head, and provided with a pinion to rotate it by means
of a cogged segment mounted on a rod extending back to the rear of the machine,

page_text: and bent in the form of a hand lever for the purpose of turning the drill or pick, so
that.its.cutting blade_may_be in either a vertical or horizontal plane as required.
The machine is mounted on wheels formed with ratchet teeth and held by pawls,
so as to secure the machine against backward movement when working on an
inclined-surface. It is provided with handles similar to a plough or hand truck by
which it may be readily moved from place to place and pushed up to its work.
It-is-made:double if preferred; that is, with two cylinders placed side by side and
working their drills alternately.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Benjamin Joseph Barnard Mills in the Great Seal Patent Office on
the 6th August 1879.
BENJAMIN JOSEPH BARNARD MILLS, of the Firm of Harris and Mills, of 23,
Southampton Buildings, in the County of Middlesex, Patent Agent. " IMPROVE-
MENTS IN COAL MINING AND ROCK DRILLING MACHINES." A communication from
abroad by Jonathan Washington Harrison, Miller, and Orange Butler, Merchant;
both of Wayne, in the State of Michigan, United States of America.
The machine is provided with a drill or pick of peculiar construction having a
concave face or end and thin concave edges. A longitudinal reciprocating notion
is imparted to this drill by means of a piston working in a horizontal cylinder and
driven by compressed air or steam, which is admitted to the ends of the cylinder
alternately by means of either a rotary or reciprocating valve, driven by a double
rotary engine consisting of a pair of eccentrics coupled together so as to stop and
start at any point, and governed by two slide valves held down by air or steam
pressure-as-is-usual-with steam engine. valves. The motion of the machine is
regulated by a throttle operated by a lever on the end of the valve-chest. A hand
wheel is mounted on the shaft of the coupled eccentrics for starting them. In each
end of the cylinder is a rubber cushion, that in the forward end through which the
piston rod carrying the pick works, being annular, and fitting over a nose pro-
jecting inward from the cylinder-head, and screw threaded to secure the rubber
cushion, the front face of the piston being recessed to receive said nose. The inner
portion of the piston rod may be round, but the outer part is of square, octagon, or
other non-circular shape, and works through a guiding sleeve fitted to rotate on
the front cylinder-head, and provided with a pinion to rotate it by means of a
cogged segment mounted on a horizontal rod extending back to the rear of the
machine, and bent upward to form a hand lever for the purpose of turning the
drill or pick, so that its cutting blade may be in either a vertical or horizontal
plane as required.
The machine is hung in a yoke mounted on wheels provided on either the edge
or face with ratchet teeth, and held by pawls so as to secure the machine against
backward movement when working on an inclined surface, or in resisting. the

page_text: hand truck, by which it may be readily moved from place to place and pushed up
to its work, and tipped up or down in front so as to cut high or low. It is made
double if preferred, that is, with two cylinders placed side by side and working
their drills or picks alternately.
And in order that the said Invention may be more clearly understood and
readily carried into effect, I will proceed aided by the accompanying Drawings more
fully to describe the same.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a plan of the machine with the extremities omitted; Figure 2 is a
longitudinal section through the centre of one of the cylinders on the line 2, 2,
Figure 1; Figure 3 is a longitudinal section of the projecting nose and pick-stock
and point omitted in Figures 1 and 2; Figure 4 is a perspective view of the pick
with a portion of the guiding rod and sleeve; Figure 5 is a transverse section of
the pick on the line 5, 5, Figure 4.
Figure 6 is a side elevation showing the preferred mode of applying the ratchet
teeth.
C, C, are a pair of cylinders mounted side by side in a yoke or carriage W₁
supported on carrying wheels W, W, which are formed or provided with ratchet
teeth w, w, to enable the wheels to be locked against backward motion by means
of lever pawls I, I, fulcrumed on the handles H, H, by means of which the machine
is advanced to its work as required. The ratchet teeth may be formed on the
peripheries of the wheels as illustrated in Figures 1 and 2, but it is preferred to
attach ratchet wheels to the faces of the wheels W, as shown in Figure 6.
A represents one of the improved pick-points mounted on a square or other
non-circular rod R attached to the piston P, one of which pistons works in each
of the cylinders C, C. The cutting face a of the pick is of concave shape as shown,
forming two prominent points, the upper and lower sides a¹, a¹, of the pick are
formed with cutting edges or sharp angles to adapt the tool to cut its way into
the surface of the wall or top of the excavation in such a manner as to effectually
prevent the deflection of the tool out of its proper line of cut by the contact of
such surface, even after the projecting points of the cutting face have become
slightly worn. The portion of the rod R outside or beyond the stuffing box of
the cylinder head C₁ has the square section indicated in Figures 2, 3, and 4, or
other non-circular shape, so that it may be guided in a box E of corresponding
shape formed to receive it in the extremity of the revolving tubular nose F. A
convenient mode of securing the nose F to the cylinder head C¹, and at the same
time permitting its rotation, is shown in Figures 1, 2, and 6, the base of the nose
being constructed with a female screw fitting a screw threaded boss c¹ on the
cylinder head, and on the exterior of said tubular nose is secured a pinion F¹¹
deriving rotation from a segment gear F2 mounted on a shaft S extending to the
rear of the machine, and bent at right angles to form a hand lever S¹. On the
shaft S is secured a stop T to limit its rotation, so that when turned as far as
possible in one direction the double pointed pick will work in a vertical plane,
and when turned as far as possible in the other direction in a horizontal plane.
The piston P is cushioned at the extremities of its stroke by rubber discs D, D¹,
the cushion D through which the piston rod must work being annular, and secured
upon an inwardly projecting boss c² threaded to receive and hold it. The forward
face of the piston P is recessed to pass over said nose. The steam or compressed
air to work the piston P reaches the ends of the cylinder through ports p, p, under
control of either a slide valve or a rotary valve V worked by double eccentrics J, J',
keyed to its shaft v, and working in a cylinder K, and constituting a double rotary
engine which is driven by the same power which works the piston P. The
cylinder K is double, being divided by a partition L and rotary head M to admit of
mounting the eccentrics at an angle to each other so as to avoid dead centres;

page_text: N, N', are the sliding abutments bearing on the peripheries of the eccentrics J, Fª,
as in rotary engines; O, O, are the steam chests of the valve-driving-engines J, J;
K, and Q throttles to control the admission of steam (or air) thereto; U, U, are
pipes admitting steam (or air) to the main valve chests V¹; u, u, are cocks or
throttles controlling said pipes; Y is a hand wheel mounted on the end of the
valve.shaft v for starting the machine.
If it be preferred to use a slide valve instead of a rotary valve V as here
represented, said slide valve will be worked by a crank or eccentric. on the shaft v_
in customary manner.
The particular construction of drill or pick herein shown and described, that is to
say, with a crescent shaped double pointed working extremity and octagon concave
faced body gives it great strength and stiffness, and at the same time adapts it to
work with freedom and good effect in deep holes. By forming the pick with sharp
èdges, as illustrated in Figures 3, 4, and 5, as well as with a sharp concave face, it
is made to accomplish with perfect success the object of running the cut in a direct
horizontal or vertical plane as may be desired, the sharp edge effectually preventing
the deflection of the pick even when the corner has become slightly worn.
Having thus described the nature of the said Invention and the mode in which
the same is carried into effect, I would have it understood that what I claim is,-
- First. The double pointed six edged concave pick, constructed as and for the
purposes herein specified.
Second. The pick A constructed with a concave cutting face a and with concave
cutting edges a' at its upper and lower sides, as illustrated in Figures 3, 4, and 5,
in combination with a suitable device for confining and guiding said pick in a
vertical or horizontal plane, substantially as herein described.
Third. The pick A constructed with a concave cutting face a and with cutting
edges a, a, at its upper and lower sides in combination with the guiding rod R,
and box or sleeve E, substantially as and for the purposes set forth.
Fourth. The combination with a suitable pick of the piston P, the cylinder C,
the valve V, and the double eccentric engine J, J', for operating the said valve.
Fifth. The combination of the piston P recessed as described, the cylinder head
C provided with inwardly projecting nose c¹, and the cushion D secured on said
internal nose as explained.
Sixth. The combination with the pick A of the non-circular rod R, the revolving
guide sleeve E, gearing F, and shaft S, as and for the purposes set forth.
Seventh. The combination in a coal or rock drilling machine of the toothed
wheels W, W, and pawls x for holding the same.
Eighth. The combination in a coal or rock drilling machine of the toothed
carrying wheels W, the holding pawls and the handles H, substantially as and for
the purposes set forth.
- Ninth. A coal or work cutting or drilling machine mounted on wheels and
adapted to be tipped or turned on a horizontal axis for cutting high or low as
required.
In witness whereof, I, the said Benjamin Joseph Barnard Mills, have hereunto
set my hand and seal, this Twenty fourth day of July, in the year of
our Lord One thousand eight hundred and seventy nine.