IMPROVEMENTS IN ROCK DRILLING MACHINES
Year: 1876

page_text: LETTERS PATENT to Charles John Copeland, of Barrow-in-Furness, in the
County of Lancaster, for the Invention of "IMPROVEMENTS IN ROCK DRILLING
MACHINES." A communication from abroad by John B. Waring, of New York,
United States of America.
Sealed the 21st October 1876, and dated the 24th May 1876.
PROVISIONAL SPECIFICATION left by the said Charles John Copeland at
the Office of the Commissioners of Patents on the 24th May 1876.
CHARLES JOHN COPELAND, of Barrow-in-Furness, in the County of Lancaster.
"IMPROVEMENTS IN ROCK DRILLING MACHINES."
These improvements have reference to the construction of rock drilling machines,
described in the Specification to J. H. Johnson's Patent, No. 1718, of 1874.
According to the present improvements, instead of arranging the screw spindlo
that serves to advance the drill cylinder centrally within the latter, and causing the
advance to be automatically effected by the motion of the drill piston, as described
in the said Specification, the said screw spindle is placed at the side, or, by preference,
below the drill cylinder, where it passes through a screwed bush on the side thereof,
and is carried in bearings in the drill frame, the spindle being turned by hand, in a
manner similar to that adopted for other constructions of rock drills. Centrally on
the back end of the drill cylinder is fixed the barrel of a small force pump, the
plunger of which is attached to the back end of the drill piston, so that at every
stroke of the latter the requisite water for clearing the bore hole is forced by the
said pump and conveyed by a pipe to the bore hole, the pump barrel being provided
with the recessary suction and delivery valves and nozzles at its back end.
For the purpose of removing the debris from vertical bore holes the drill spindle
is formed with a series of circular steps or shoulders along its length, the spindle
being made to taper in a downward direction from the outer edge of one such
shoulder to the inner edge of the shoulder below. By this means, when the spindle per-
forms its down stroke, the small debris will pass between it and the side of the bore
hole and will lodge upon the said shoulders, and will consequently be raised up on
the rising of the drill spindle.
For partially rotating the drill spindle at each back stroke a ratchet wheel is fixed
on the front end of the piston rod, in gear with which is a pawl carried by an arm
[Price Gd.1

page_text: fitting loose on the piston rod and having a tail which works in an inclined slot,
formed in a bracket or guide projecting from the side of the drill cylinder, so that as
the piston rod, and with it the ratchet wheel and pawl, travel backward and for-
ward, the motion imparted to the arm carrying the pawl by the inclined slot will
effect the partial rotation of the drill spindle. A spring pawl fixed to the bracket
prevents the ratchet wheel and piston rod from turning back again.
The boring tool is constructed with two parallel chisel edges extending right
across its face, and with two other cutting edges formed on the circumference of the
tool on each side of the chisel edges, so that rs the latter, by the jumping action of the
drill, cut away the bottom of the bore hole, the lateral cutting edges will by the
gradual rotation of the drill cut the sides of the bore hole smooth and cylindrical.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Charles John Copeland in the Great Scal Patent Office on the 30th
October 1876.
CHARLES JOHN COPELAND, of Barrow-in-Furness, in the County of Lancaster.
"IMPROVEMENTS IN ROCK DRILLING MACHINES." A communication from abroad by
John B. Waring, of New York, United States of America.
These improvements have reference to the construction of rock drilling machines,
described in the Specification to J. H. Johnson's Patent, No. 1718, of 1874.
According to the present improvements, instead of arranging the screw spindlo
that serves to advance the drill cylinder centrally within the latter, and causing the
alvance to be automatically effected by the motion of the drill pistou, as described
in the said Specification, the said screw spindle is placed at the side or by preference
below the drill cylinder, where it passes through a screwed bush on the side thereof,
and is carried in bearings in the drill frame, the spindle being turned by hand, in a
manner similar to that adopted for other constructions of rock drills. Centrally on
the back end of the drill cylinder is fixed the barrel of a small force pump, the plunger
of which is attached to the back end of the drill piston, so that at every stroke of
the latter tho requisite water for clearing the bore hole is forced by the said pump
and conveyed by a pipe to the bore hole, the pump barrel being provided with the
necessary suction and delivery valves and nozzles at its back end.
For the purpose of removing the debris from vertical bore holes the drill spindle
is formed with a series of circular steps or shoulders along its length, the spindle
being made to taper in a downward direction from the outer edge of one such
shoulder to the inner edge of the shoulder below. By this means, when the spindle
performs its downstroke, the small debris will pass between it and the side of the bore
hole, and will lodge upon the said shoulders, and will consequently be raised up on
the rising of the drill spindle.
For partially rotating the drill spindle at each back stroke at ratchet wheel is
fixed on the front end of the piston rod, in gear with which is a pawl carried by an
arm fitting loose on the piston rod, and having a tail which works in an inclined
slot formed in a bracket or guide projecting from the side of the drill cylinder, so
that as the piston rod and with it the ratchet wheel and pawl travel backward and
forward the motion imparted to the arm carrying the pawl by the inclined slot will
effect the partial rotation of the drill spindle. A spring pawl fixed to the bracket
prevents the ratchet wheel and piston rod from turning back again.
The boring tool is constructed with two parallel chisel edges extending right
across its face, and with two other cutting edges formed on the circumference of the
tool on each side of the chisel edges, so that as the latter by the jumping action of
the drill cut away the bottom of the bore hole the lateral cutting edges will by the
gradual rotation of the drill cut the sides of the bore hole smooth and cylindrical.

page_text: DESCRIPTION OF THE DRAWINGS.
Fig. 1 represents a longitudinal section, and Fig. 2 a plan of a rock drill of the
kind above referred to, modified according to the present improvements.
A is the screw for advancing the drill as the hole becomes deeponed. Instead of
5 its boing mounted in the axis of the drill cylinder it is mounted at the side of the
cylinder, or under it, as shewn in Fig. 1, so that it works in a nut B attached to
the cylinder, which it causes to advance or recede, according as it is turned in the
one direction or the other by the handle C. A plunger D attached to the working
piston works in a barrel E attached to the end of the cylinder, so as to act as a
force pump, which is provided with suction and delivery valves e and f, sending at
every back stroke of the drill a jet of water by the discharge pipe F, and a suitable
flexible tube attached thereto into the bore hole for the purpose of washing out the
debris.
The partial rotation of the drill at overy stroke is offected in the following
manner: A ratchet wheel G is fixed on the piston rod between two checks H, H,
forming a fork, from the back of which projects a stud I that works in an inclined
slot in an arm K attached to the drill cylinder.
Fig. 3 represents a side view of this arm, and Fig. 4 represents a section to an
enlarged scale through the ratchet wheel G and arm K. A spring pawl L is mounted
on a pin between the cheeks H, and another spring pawl M is mounted on the
arm K, the front edge of M being sufficiently wide to remain always in gear with
the ratchet wheel G while it makes its stroko to and fro. As the drill makes its
forward stroke, the pawl L being caused to move downwards with the cheeks H by
the movement of the stud I along the inclined slot in K, slips over several teeth of
the ratchet wheel G, which is prevented by the pawl M from turning in the same
direction; then during the back stroke of the drill, the pawlL moving upwards, turns
the ratchet wheel G partly round in the direction of the arrow, the pawl M slipping
the teeth as they pass.
The above described improved construction of rock drill may also be used without
the plunger D and barrel E for supplying the water to the bore hole, this operation
being effected by a separate pump. In this case the advantage would be gained of
rendering the entire area of the back of the piston available for the action of the
fluid pressure, whereby I am enabled to obtain the same penetrating power with &
sinaller and consequently lighter machine.
For more effectually clearing the debris from the boro hole the stem of the drill
is made, as shewn in Fig. 5, with successive shoulders N, and the portions between
them tapering from each to a smaller diameter under tho next in order; thus at the
back stroke of the drill in the direction of the arrow the debris is moved by each
of the shoulders N outwards, whilst during the forward stroke in the opposito
direction the tapering portions of the stem have comparatively little effect in
pushing the debris inwards.
Figs. 6 and 7 represents side views, and Fig. 8 an end view of the improved boring
tool; it has two parallel edges P, P, extending across its face, and two cutting
edges QQ, at each side, the former serving to deepen the bore hole, and the latter
acting by the gradual rotation of the drill to smooth its interior surface.
Having thus described the nature of this Invention, and in what mannor the
same is to be performed as communicated to me by my foreign correspondent, I
claim as improvements in rock drills of the kind referred to,-
First. Mounting the advancing screw at the side of or under the cylinder, and
attaching to the piston a plunger working in a barrel for the purpose of forcing
water into the bore hole, substantially as described.
Second. Effecting the partial rotation of the drill at each back stroke by means of
a pawl acting on a ratchet whoel fixed on the piston rod, the said pawl being caused
to move partly round the axis of the wheel by a stud on its framing moving along
an inclined slot, substantially as heroin described.

page_text: Third. Constructing the drill stem with successive shoulders and parts tapering
between them, substantially as and for the purpose herein set forth.
Fourth. The construction of the boring tool with two cutting edges on the face,
and with cutting edges on the sides, substantially as herein described with reference
to Figs. 6, 7, and 8 of the accompanying Drawings.
In witness whereof, I, the said Charles John Copeland, have hereunto set my
•
hand and seal, this Twenty-fifth day of October, in the year of our Lord
One thousand eight hundred and seventy-six.
CHARLES JOHN COPELAND. (L.S.)