IMPROVEMENTS IN MACHINERY FOR DRILLING, PERFORATING, OR BORING ROCKS AND OTHER HARD SUBSTANCES
Year: 1876

page_text: LETTERS PATENT to William Wallace Dunn, of San Francisco, California,
United States of America, now of No. 8, Southampton Buildings, London,
Engineer, for the Invention of "IMPROVEMENTS IN MACHINERY FOR DRILLING,
PERFORATING, OR BORING ROCKS AND OTHER HARD SUBSTANCES."
Sealed the 21st November 1876, and dated the 25th May 1876.
PROVISIONAL SPECIFICATION left by the said William Wallace Dunn at
the Office of the Commissioners of Patents on the 25th May 1876.
WILLIAM WALLACE DUNN, of San Francisco, California, United States of
America, now of No. 8, Southampton Buildings, London, Engineer. " IMPROVE-
MENTS IN MACHINERY FOR DRILLING, PERFORATING, OR BORING ROCKS AND OTHER
HARD SUBSTANCES."
This Invention relates to machinery for drilling or boring holes in rock and
other hard mineral substances in mining, tunnelling, quarrying, and similar opera-
tions.
The machines to which my Invention relates are of that class wherein the
drilling or perforating implement is moved to and fro and turned on its axis by a
piston, which has a reciprocating and turning motion within a cylinder that is
supplied with steam, air, or other actuating fluid directed alternately into both
ends of the cylinder through the agency of a suitable valve.
The said Invention relates, first, to a novel arrangement of the slide valve and
steam and exhaust ports of a rock drilling machine, and parts for operating the
said valve. The said slide valve and ports are so formed and arranged that the
valve slides to and fro transversely across the cylinder instead of longitudinally
with the same. This motion of the slide valve is obtained through the medium of
a rocking shaft and arms arranged above the cylinder, the said shaft extending
forward from the valve chest preferably in a downwardly inclined direction. This
rocking shaft has on it an arm which connects with the slide valve and two other
arms, which are arranged to be acted upon by a conical protuberance on the piston
rod in such a manner that the latter by its to and fro movement imparts a rocking
motion to the said shaft, and thereby produces the required to and fro motion of
the slide valve across the port face of the cylinder; but although I prefer this
arrangement of the valve to move across the cylinder instead of longitudinally
[Price Sill

page_text: with the axis of the same I sometimes modify this part of my Invention by
arranging the said valve to move in a longitudinal direction upon the cylinder, and
operate the same by two rocking arms carried on suitable shafts which have other
arms arranged to be acted upon by the aforesaid conical protuberance on the piston
rod. The said rocking shafts are passed through packing boxes filled with hemp
or other packing to prevent their jarring or vibrating during the operation of the
inachine.
The feed or advance of the drill or perforating implement is effected by the
following mechanism, which constitutes another part of my said Invention :-The
feed screw is arranged at the side of the cylinder and passes through a feed
nut attached to the same. Parallel with the piston rod I arrango another rocking
shaft, which has on it two arius arranged to be actuated by opposite sides of the
aforesaid conical piece on the piston rod, so as to produce the required rocking or
vibrating motion of the said shaft. The said shaft also has another arm to which
are pivoted two pawls that take into the teeth of a ratchet wheel on the feed screw,
the points of these pawls are formed to act upon the ratchet wheel in opposite
directions, so that one pushes and the other pulls the ratched wheel around in the
sane direction, and the drill therefore has a continuous feeding or advance motion
during the operation of the machine.
When the feed mechanism is to be operated by hand I provide the end of the
feed screw with a hand lever, and I provide a sounder, which acts when the feed
is not fast enough. This sounder consists of a small lever pivoted on the cylinder
frame, and which has a spring to bring it into contact with the cones on the piston
rod; at or near the front of the machine I place a small stud which is struck by the
sounder lever when the feed requires to be accelerated, and causes the levor to
indicate the need of acceloration by the tapping sound produced by the vibrating of
the said lever.
Another part of the said Invention relates to the mechanism for causing the
rotation of the piston rod with the drill or perforator.
For this purpose I form the head or cover at the rear end of the cylinder with a
deep cavity or recess for the reception of a ratchet wheel and devices for controlling
the same. Two pawls are arranged to take into this wheel at points diametrically
opposite cach other. They are formed with bosses which drop into suitable cavities,
and they are kept in place by stop pieces cast in the head. The springs of these
pawls are held by a small tooth formed and fitted into a notch in studs fixed in the
head or cover.
By this construction and arrangement of the parts I avoid all screws and similar
fastenings for securing these parts in place. The ratchet wheel has a central square
hole through which a rod is passed, this rod does not project at the rear through the
cylinder cover but extends forward into the piston rod, which is made hollow
for a portion of its length to receive this square rod and slide to and fro over it.
The said square rod has a head at the back or inner side of the ratchet wheel, its
part which extends inside the piston rod is twisted or made spiral, and the piston
rod has a steel bush with a correspondingly formed aperture which fits the spiral
rod. The head or cover has a plate placed over the recess or cavity enclosing the
ratchet wheel, and which is secured to the head by bolts and nuts. The said spiral
rod extends through this plate into the piston rod. The effect of the spiral or twisted
rod in combination with the ratchet wheel and pawls is that during the forward
stroke or motion of the piston no rotation of the same is produced, but during the
backward stroke or movement of the piston the same and the drill or perforating
implement are turned on their axis a distance equal to one tooth of the said
wheel, so that the said drill does not strike two blows in succession in exactly
the same place.
Another part of my Invention relates to a device for securing the drill or perforating
implement securely in the end of the piston rod. For this purpose I form an aperture
near the end of the said rod, in which I fit a picco termed a die, which bears on
the shank or stem of the drill. Over the end of the piston rod I fit a ring or collar,

page_text: and at the side of the rod opposite the said die I drive a key between the said collar
and rod, thereby causing the die to bind tightly on the drill shank or stem.
According to another part of my Invention I provide the means for automatically
stopping a rock drilling inachine when the drill has been fed forward to the full
extent of the fed screw. For this purpose I provide the supply pipe or passage of
the engine with a throttle valve, which has outside of the said pipe or passage on
its axis or rod a lever arm or crank. This lever arm or crank is arranged in such a
position in relation to a fixed cam or projection on the forward part of the cylinder
frame that the said arm or crank will, when the drill has been fed forward to its
full extent, act on the said lever arm or crank to close the said valve, thereby cutting
off the supply of the steam or other actuating fluid and stopping the machine.
This
Another part of my said Invention relates to the construction of the supporting
stands or frames for rock drilling machines. I construct one of my improved
stands in the form of a frame with three short adjustable legs. This stand has a
round cross bar on which I mount a clamp provided with a pinching screw.
clamp is formed with a conical socket for the reception of a conical trunnion on the
cylinder. And I thus support the said cylinder and its adjuncts on a universal
joint whereby the machine can be adjusted to work at any desired angle and in
any required vertical plane.
I also construct a stand consisting of a vertical bar or tube, forming a pillar,
supported upon a base or foot. The said base is perforated to furnish a secure hold
to claws or points at the bottom of the vertical bar or pillar. The latter is provided
at its upper end with an adjusting screw to secure it against the roof or top of the
tunnel or cutting.
On the said pillar I mount a bearing piece formed with clamp-
ing jaws, and which is adjustable upon the said pillar. This bearing piece carries
a cranked bar, which is designed to carry the drilling mathine, and which can be
so adjusted as to permit the drill or perforater to act in any required direction.
The said bearing piece is connected to a chain, which passes over a pulley at or
near the top of the pillar or standard, and is connected to a windlass or winch
secured upon the base or foot of the stand, on the side of the pillar opposite to that
on which the drilling machine is supported. By means of this windlass the said
machine can be readily adjusted to work at any desired height. This vertical pillar
or standard provided with a bearing piece, cranked supporting bar, and winch is in
some instances mounted upon a wheeled truck or carriage which is also provided
with a water tank for supplying water to the drill or for other purposes.
I also modify the construction of the said frames or stands by providing the same
with extensible jointed arms at both sides of the frame. These arms are connected
at their extremities by cross bars on which the drilling machines are mounted
with a capability of turning thereon. These extensible arms permit the said
machines to be extended and work considerably beyond the frame or stand. The
water tank is in this instance mounted upon the top of the stand so that the
attendant can pass below it to and from the drilling machines. Each pair of
adjustable arms is connected by chains to a separate windlass, so that the machine
or machines carried by each pair of arms may be adjusted independently of the
machines carried by the other pair.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Wallace Dunn in the Great Seal Patent Office on the
24th November 1876.
WILLIAM WALLACE DUNN, of San Francisco, California, United States of
America, now of 8, Southampton Buildings, London, Engineer. "IMPROVEMENTS
IN MACHINERY FOR DRILLING, PERFORATING, OR BORING ROCKS AND OTHER HARD
SUBSTANCES."
This Invention relates to machinery for drilling or boring holes in rock and other
hard mineral substances in mining, tunnelling, quarrying, and similar operations.

page_text: The machines to which my Invention relates are of that class wherein the drilling
or perforating implement is moved to and fro and turned on its axis by a piston
that has a reciprocating and turning motion within a cylinder which is supplied
with steam, air, or other actuating fluid directed alternately into both ends of the
cylinder through the agency of a suitable valve.
The said improvements are fully illustrated by the accompanying Drawings,
which I will now proceed to describe.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a plan of a machine constructed according to my Invention, some
portions of the same being removed.
Figure 2 is a longitudinal vertical section through the centre of the said
machine.
Figure 3 is a transverse section on the line x, x, Figure 1, shewing various parts
not shewn in Figure 1.
Figure 4 is a plan shewing the said machine provided with my improved auto-
matic feed and stopping mechanism herein-after described.
Figure 5 is a rear end elevation of Figure 4.
Figure 6 is a vertical transverse section on the line y, y, Figure 4.
Figures 7 to 9 shew details of the said Invention detached and herein-after
described.
Figures 10 and 11 shew a plan and elevation of a drifting frame forming part of
my Invention.
Figure 12 is a section on the line 2, 2, Figure 10.
Figure 13 is a perspective view of a stand or pillar frame for supporting my
improved drilling machine.
Figures 14 and 15 shew a side and front elevation of another frame mounted on
a truck or trolly.
Figure 16 is a side elevation of another supporting frame forming part of the
said Invention. Like letters indicate the same parts throughout the Drawings.
A is the main frame of the drilling machine; a is the cylinder; b is the piston;
b is the piston rod; c is the drill or perforator; d is the valve chest or casing; e is
the valve; e, e, e³, b², are parts of the mechanism for operating the same; fis the
feed screw; fffs, are parts of the devices for rotating the said screw; g is the
feed nut; h, h, h³, are parts of the mechanism for rotating the piston and drill. The
other parts of the machinery arc herein-after described.
The said Invention relates, first, to a novel arrangement of the slide valve and
steam and exhaust ports and devices for operating the said valve.
According to this part of my Invention the slide valve e and ports d* and d¹ are so
formed and arranged that the said valve slides to and fro transversely or laterally
across the port face of the cylinder a instead of moving in the usual manner end-
wise, or in the direction of the cylinder's length.
As clearly shewn in Figures 1, 2, and 3, this motion of the slide valve is very advan-
tageously obtained through the medium of the rocking shaft e¹ and arms e arranged
above the cylinder. The said shaft extends forward from the valve chest d, and its
outer extremity is supported in a bracket c. This rocking shaft also has on it
another arm which works through the exhaust port and projects into the cavity
of the slide valve e, as shewn in Figures 2 and 3.
The two arms e, as shewn in Figure 6, are arranged to be acted upon by different
portions of a conical protuberance or double inclined plane be on the piston rod b¹
in such a manner that the latter by its to and fro movement imparts a rocking
motion to the shaft e¹, and thereby produces the required to-and-fro motion of the
slide valve e across the port face of the cylinder.
It will be obvious to those familiar with this class of machinery that by the above
described arrangement I obtain a direct working of the slide valve in a more
simple manner than would be practicable with the ordinary arrangement of the
valve and ports.

page_text: As a modification of the above instead of arranging the rocking arms c², as shown
in Figures 2, 4, and 6, I may fix them on the part of the shaft e¹, which is within
the casing between the cylinder and valve chest, the said arms then projecting
through the inlet ports at the ends of the cylinder into the latter and the two cones
being formed on or placed near the piston.
In this arrangement the shaft e' is provided with suitable packing around it to
prevent any communication between the two ports. I prefer to have this packing
in two halves or pieces of suitable packing material formed to embrace the shaft,
and placed within a small stuffing box through which the said shaft slides. And I
provide this stuffing box with a screw on both sides to tighten the packing as
required.
But although I prefer this arrangement of the valve to move across the cylinder
instead of longitudinally with the axis of the same, I sometimes modify this part
of my Invention by arranging the said valve to move in the ordinary manner, that
is to say, in a longitudinal direction upon the cylinder, and operate the same by
two rocking arms carried on suitable shafts, which have other arms arranged to be
acted upon by the aforesaid conical protuberance on the piston rod. The said
rocking shafts may be supported in packing boxes fillod with hemp or other packing
to prevent their jarring or vibrating during the operation of the machine. In-
stead of having the rocking shaft e parallel with the piston rod, as shewn in
Figure 1, I may arrange the said shaft, obliquely to the piston rod, that is to say,
it may extend forward from the valve in an inclined or slanting direction, and
thereby bring its forward end nearer to the piston rod so that the said arms may
be shortened if necessary.
The feed or advance of the drill or perforating implement is effected by the
following mechanism, which constitutes another part of my said Invention: -Tho
feed screw is arranged at the bottom or side of the cylinder a, and passes through
a feed nut g attached to or held by the frane A on which the cylinder and its
adjuncts slido. Parallel with the piston rod I arrange another rocking shaft f¹,
which has on it an arm f arranged to be actuated by the side of the aforesaid
double conical piece b on the piston rod b to impart to the said shaft a rocking or
vibratory motion. Near the arm f I fix in the frame a stop a* to limit the motion
of the said arın and keep it in the proper position to be acted on by the said
conical piece. And I also place near it a spring f* which tends always to keep
the arm up to the stop. The shaft f¹also has another arm f³, to which are pivoted
two pawls f, f³, that take into the teeth of a ratchet wheel ƒ on the feed screw f.
The points of these pawls are formed to act upon the ratchet wheel f" in opposite
directions, so that one pushes and the other pulls the said ratchet wheel around
and the latter therefore has a continuous feeding or advance motion during the
operation of the machine. And one result of this arrangement of the two pawis
is that no separate retaining pawl is required to prevent the backward turning of
When the feed mechanism is to be operated by hand I provide the end
of the feed screw f with a hand lever in place of the ratchet wheel, and I provide a
sounder, as shown in Figure 1, which acts when the machine does not feed quickly
enough. This sounder consists of a small lever k pivoted on the cylinder frame
at, and which has a spring to bring it into contact with the conical or
inclined piece on the piston rod b¹. At or near the front of the machine I place
a small stud l, which is struck by the sounder lever when the feed requires to be
accelerated, and causes the lever to indicate the need of acceleration by its vibration
and consequent tapping sound.
the same.
Another part of my said Invention relates to the mechanism for causing the
rotation of the piston rod b¹, and with it the drill or perforator c.
For this pur-
pose I form the head or cover at the rear end of the cylinder a with a deep
cavity or recess for the reception of a ratchet wheel h', and devices for controlling
Two pawls, h³, are arranged to take into this wheel at points
diametrically opposite each other, as shewn in Figure 7. These pawls are not fitted
on pins or pivots, but are formed with bosses which drop into small cavities
the same.

page_text: in the head, and they are kept in place by stop pieces h³ cast in the said head.
The springs " of these pawls are held by small teeth formed and fitted into
notches in studs fixed in the head or cover h. By this construction and arrange-
ment of the parts I avoid all screws and similar fastenings for securing these parts
in place.
The
The ratchet wheel ¹ has a square central hole through which a rod h³ is passed.
This rod does not project at the rear through the cylinder cover h but extends
forward into the piston rod b', which is made hollow for a portion of its length in
order that it may receive this square rod and slide to and fro over the same.
said square rod has a head hº at the back or inner side of the ratchet wheel h¹;
its part which extends inside the piston rod is twisted or made spiral, and the
piston rod b¹ has a steel bush or die with a correspondingly formed aperture
which fits the spiral rod. The head or cover h has a plate h placed over the
recess or cavity enclosing the ratchet wheel, and which is secured to the head by
bolts and nuts, as shewn in Figure 2. The said spiral rod extends through this
plate into the piston rod b. The effect of the combination of this spiral or twisted
rod with the said ratchet wheel and pawls is that during the forward stroke or
motion of the piston b no rotation of the same is produced, but during the back-
ward stroke or movement of the piston the same and the drill or perforating implo-
ment have a partial rotation on their axis a distance corresponding with the
distance between the teeth of the said wheel, so that the said drill does not strike
the rock or other substance twice in succession in exactly the same place.
Another part of my said Invention relates to a device for securing the drill or
perforating implement securely in the end of the piston rod b. For this purpose I
may forin an aperture near the end of the said rod wherein I fit a piece termed a
die which bears on the shank or stem of the drill. Over the end of the piston rod
I fit a ring or collar, and at the side of the rod opposite the said die I drive a key
between the said collar and rod, thereby causing the die to bind tightly on the drill
shank or stem. But I prefer to use the device shewn in Figures 8 and 9, in which
I fit the die or key n into a recess cut through one side of the piston rod b¹, so that
it bears on the shank of the drill c and fits the head n¹ of the die in a recess in the
collar 0, and I secure the said die by a set screw passed through the collar o.
According to another part of my Invention I provide a rock drilling machine with
incans for automatically stopping the working of the same when the drill has been
fed forward to the full extent of the feed screw. For this purpose I provide the
exhaust or supply pipe or passage of the cylinder a with a throttle valve h, which
has outside of the said pipe or passage on its axis or rod a lever arm or crank
provided with double flat surfaces and a spring to keep the valve in either
position. This lever arm or crank is arranged in such a position in relation to a
fixed cam or projection on the forward part of the frame A that when the drill
has becu fed forward to its full extent the said cam or projection will act on the
lever arm or crank in such a manner as to close the valve 7, thereby cutting off
the supply or stopping the escape of the steam or other actuating fluid and stopping
the working of the machine.
Another part of my said Invention relates to the construction of the supporting
stands or frames for rock drilling machines. In Figures 10, 11, and 12, I have
shewn a frame or stand which I term a drifting frame. This frame or stand has
three short adjustable legs t, it also has a round boss t¹ fitted on a square cross bar t²
on which boss I mount a clamp t³ provided with a pinching screw. This clamp is
formed with a conical socket t' for the reception of a conical trunnion on the
cylinder, and I thus support the drilling machine on a universal joint whereby the
said machine can be adjusted to work at any desired angle and in any required
vertical plane. The said boss is held in place on the square bar by a key or cotter,
which may be readily taken out to permit the said boss to be moved endwise on the
square bar or cross tree. This arrangement is very convenient in cases where long
or deep holes have to be bored in the rock or other hard substance as it permits the
drill to be easily drawn out of such holes.

page_text: I also construct a stand consisting of a vertical bar tube or pillar u, supported
upon a base or foot u, as shewn in Figure 13. The said base is perforated to furnish
a secure hold to claws or points us at the bottom of the vertical bar or pillar. The
latter is provided at its upper end with an adjusting screw u" to secure it against
the roof or top of the tunnel or cutting. On the said pillar I mount a bearing
piece u formed with clamping jaws and which is adjustable upon the said pillar.
This bearing piece is fitted with a cranked bar u, which is designed to carry the
drilling machine, and can be so adjusted as to permit the drill or perforator to act
in any required direction. The said bearing piece is connected to a chain u, which
passes over a pulley or sheaf wheel 7 at or near the top of the pillar or standard u,
and is connected to a windlass or winch us secured upon the base or foot of the
stand on the side of the pillar u opposite to that on which the drilling machine is
supported. By means of this windlass the said machine can be readily adjusted to
work at any desired height. This vortical pillar or standard u provided with a
bearing piece u, cranked supporting bar us, and winch is in some instances mounted
upon a wheeled truck or carriage v, as shown in Figures 14 and 15. This truck or
carriage is provided with a water tank v¹ for supplying water to the drill or for
other purposes.
I also modify the construction of the said frames or stands, as shewn in Figure 16,
by providing the same with extensible jointed arms wat both sides of the frame.
These arms are connected at their extremities 20* by cross bars, on which the
drilling machines are mounted with a capability of turning thereon. These exten-
sible arms permit the drilling machines to be extended and work considerably beyond
the frame or stand, and to be drawn in or near to the frame when desirable. The
water tank is in this instance mounted upon the top of the stand, so that when
working in a tunnel or cutting, the attendant can pass below it to and from the
drilling machine. I admit air or other fluid from the reservoir or pump which
supplies the drill cylinder to the water tank, so that the same pressure that works
the drill supplies the same with water to facilitate its action on thic rock or other
substance. Each pair of adjustable arms is connected by chains w¹ to a separate
windlass so that the drilling machine or machines carried by each pair of arms may
be adjusted independently of the machine or machines carried by the other pair.
Having thus fully described my said Invention and the manner of performing the
same, I wish it understood that I claim-
First. In combination with the cylinder of a rock drilling machine the slide valve
and ports so arranged that the said slide valve opens and closes the ports by moving
laterally or transversely on the port face or across the cylinder, the said valve being
operated by the piston rod through the medium of the double conical surface thereon
and the arms on the valve shaft or spindle as above set forth.
Second. The modification of the mechanism for operating the said slide valve,
wherein the arms acted on by the conical surfaces on the piston rod project through
the ports into the cylinder and comprising the peculiar manner of packing the said
shaft or spindle between the ports as above set forth.
Third. In a rock drilling machine the devices for effecting the feed or advance of
the drill, consisting of the combination of parts whereby the conical surface on the
piston rod communicates motion to the ratchet wheel on the feed screw as above
set forth.
Fourth. The sounder, arranged in combination with the piston rod, and operating
to indicate the necessity for accelerating the feed of the drill when the feed is effected
by hand as above set forth.
Fifth. The mechanism for effecting the rotation of the piston rod and drill or
perforator, consisting of the devices enclosed in the cylinder head in combination
with the spiral rod and the die in the piston or piston rod as above set forth.
Sixth. In combination with the aforesaid cylinder and its adjuncts the devices
whereby the working of the machine is stopped when the drill or perforator has
been fed or advanced to the full extent of the feed movement of the cylinder and
its adjuncts on the frame as above set forth.

page_text: Seventh. The devices for securing the drill or perforator in the piston rod as above
set forth.
Eighth. The drifting frame, shown in Figures 10 and 12, provided with means
for supporting the drilling machine, and with devices for facilitating the withdrawal
of the drill or perforator from long or deep holes as above set forth.
Ninth. The frame or stand consisting of the vertical tube or pillar secured upon
a base plate, or upon a truck or carriage, and which supports a cranked bar whercon
the drilling machine is to be mounted, which bar is adjustable on the said pillar
and is provided with means for raising and lowering it on the latter as above set
forth.
Tonth. The frame or stand provided with the extensible arms for supporting the
drilling machines and with means for adjusting the said arms, and the combination
of these devices with the cistern or tank, placed at the upper part of the said frame
as above set forth and for the purpose specified.
Eleventh. The machine for drilling, boring, or perforating rocks or other hard
substances with its various parts constructed and combined as shown in Figures 1
to 9 of the accompanying Drawings and operating as above set forth.
In witness whereof, I, the said William Wallace Dunn, have hereunto set my
hand and scal, this Twenty-seventh day of October, in the year of our
Lord One thousand eight hundred and seventy-six.