Improvements in Rock Drilling Apparatus..
Year: 1898

page_text: Date of Application, 24th May, 1898-Accepted, 1st Oct., 1898
COMPLETE SPECIFICATION.
Improvements in Rock Drilling Apparatus..
I, JOHN GEORGE LEYNER, of No. 901, Broadway Street, Denver, Arapahoo
County, State of Colorado, United States of America, Inventor and Manufacturer
of Rock-drilling Machinery, do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and
ascertained in and by the following statements:-
.
My invention relates to improvements in air or steam rock drilling engines
adapted to expel rock cuttings from holes while drilling them, and the objects of
my invention are, first, to provide a rock drilling engine that will discharge
against the bottom of a hole while drilling it, a jet of the engine's actuating air
or steam combined with a stream of water under pressure; second, to provide
means for regulating the flow of the water; third, to provide means for conveying
the water through the drilling engine and its drill bit and through the drill bit's
cutting point to the bottom of the hole being drilled; fourth, to provide means
for uniting the air and water in the shank of the drill bit; fifth, to provide means
for connecting the water supply to either side of the engine; sixth, to provide an
operating rock drilling engine in which the drill bit is stationary relative to the
reciprocal movements of the piston, and is loosely and non-clampably supported by
the drilling engine and is arranged to be instantly withdrawn therefrom or inserted
therein at the will of the operator and that is adapted to be intermittently rotated
step by step therein by the reciprocating and intermittent rotary movement of the
piston, and which is adapted to convey a portion of the piston's actuated fluid
from the engine's cylinder combined with a jet of water to the bottom of holes
while drilling them seventh, to provide a rock drilling engine adapted to drive
the rock cuttings from holes while drilling them and to lay the rock dust formed
by the drill bit while cutting or drilling into rock.
attain these objects by the mechanism illustrated in the accompanying
drawings, in which,
Fig. 1 is a longitudinal section of an air or steam drilling engine embodying
my invention; Fig. 2 an end view of the drill bit and of the engine; Fig. 3 a
section on line A of Fig. 1; Fig. 4 a section on line B of Fig. 1; Fig. 5, a section
on line C of Fig. 1; Fig. 6 a section on the zig-zag line D of Fig. 1, but showing
only that part of the auxiliary cylinder head that is directly above the washer
and not the offset portion over the ratchet, but showing a section through the
ratchet-bar's head and the pawls; Fig. 7 an end elevation of the feed end of the
machine; Fig. 8 a side view of the drill bit; Fig. 9 an end elevation of the striking
end of the drill bit and Fig. 10 a section on line E through the drill holding nut
and sleeve of the front head of Fig. 1, and Fig. 11 a side elevation of the rifle bar.
Similar letters of reference refer to similar parts throughout the several views.
Referring to Fig. 1, DD, designates the cylinder; EE, the piston; F. the
steam chest; G, the valve: H, the guide shell in which the cylinder is slidably
mounted, and I, the feed screw of a drilling engine. The drill feeding mechanism
comprises the screw I, the operating handle J. The handle J threads onto the
D

page_text: end of the screw and on the screw between, the handle and flange K, a washer L
is placed which bears against a shoulder M, formed on the screw. The screw is
also provided with a collar N, which projects into a recess O, formed in the flange
to receive it. This collar takes the backward thrust of the screw and in operation
there is almost always a continuous backward thrust as the drilling engine recoils
from the striking of the drill against the rock. The handle J is screwed against
the washer L, which bears against the shoulder M and the round portion P of the
screw between the shoulder and the collar is made a little wider than the surround-
ing bearing of the flange so that the collar and washer do not pinch the flange
and the screw can rotate freely in the flange. On the extreme end of the screw
beyond the handle I screw a nut Q tightly against the handle. The feed screw
supporting flange L is provided with two opposite laterally extending ears R and S,
by which it is bolted to the main, guide shell of the drilling engine by the bolts T
and T. These bolts pass freely through the ears and the flange U of the guide-
shell and are secured thereto by nuts Vand W and V and W, which are threaded
to their ends and which are tightened against the side of the lugs and flange.
The feed screw is threaded through a nut X, which is rigidly supported in, a
depending lug Y formed on the bottom of the cylinder D D. This nut is clamped
in said lug by a nut Y¹. On the opposite end of the screw I thread a nut Z to
prevent the nut X and the drilling engine being fed off from the screw. The
cylinder is provided with a front cylinder head 2, which is threaded to the end of
the cylinder. A sleeve 3 is rotatively mounted in the axial bore 4 cf the cylinder
head. At its inner end the sleeve has an enlarged round flange portion 5, which.
projects and fits loosely into a counterbore in the inner end of the cylinder head.
The flange portion of the sleeve is larger in diameter than the bore of the cylinder
and its inner end bears against the bottom of the counterbore in which the
cylinder head screws. Between the opposite side of the flange and the bottom of
the counterbore of the cylinder head and around the body of the sleeve I place a
steel buffer ring 6 which is provided with a key portion 7 that fits loosely into a
key-way 8 in the cylinder head to prevent its turning on the sleeve. A rubber
buffer ring 9 is also placed at the side of the steel ring and a second steel ring 10
is placed on the opposite side of the rubber buffer ring in the bottom of the counter-
bore. These rings are adapted to cushion the blows of the piston that strike against
the end of the sleeve which happens when the engine is running and the drill-
bit is not in striking position against rock. From two opposite sides of the
flange head of the sleeve, two rods 11 project and extend loosely into holes 12
drilled into the piston. The entrance to these holes is provided with bushings 13
in which the rods fit slidably. In the section in Fig. 1, I illustrate but two rods
extending from the sleeve into the piston but in Fig. 4, I illustrate three rods and
in the largest size drilling engines I would use four. For the smallest size
drilling engines two will be sufficient to turn the drill. Three however are prefer-
able for the average size drilling engines. The piston reciprocates on these rods
which are rigidly secured to the sleeve and through the medium of the rifle-bar 14
and its ratchet head 15, the pawls 16 and these rods, the piston rotatively turns
the sleeve step by step. The means illustrated and just described for turning the
piston step by step through the medium of the rifle-bar is common to most all
air drilling engines in use.
The essential object of this present invention is to convey a combined jet of com-
mingled compressed air and water from the cylinder and from a source of water
supply through the drill bit to its cutting point' to blow out and expel the rock
cutting from holes while drilling them and to also lay the dust formed by cutting
the rock. The amount of dust made in drilling a hole a few feet deep in dry rock
without water in a breast of an average sized mining tunnel is sufficient to fill it
full and its presence is practically unbearable to the operators of the drilling
engine and the use of some medium to lay it in the hole is necessary. Water is
used with the common type of drilling engine by pouring it in a down-hole and
by forcing it into up-holes when necessary by any convenient means.

page_text: In order to expel the rock cuttings from the holes with the engine's actuating
fluid and at the same time allay the dust with water it is necessary that they be
introduced into the holes in a manner in which they will work together and in.
which each will perform its special work without neutralizing the effect of the
other. Should the air be conducted axially through the drill bit to the bottom
of a hole and water be forced into the hole, around the drill bit, the air and water
would be moving in opposite directions and would meet and the action of both
would be defeated. It is therefore necessary to obtain the best results that the
air and water should be united into a single substantially integral jet and be
delivered at the bottom of the hole through a close conduit (that is to say a
continuous passage either enclosed within the metal of the drill shank itself, such
as would be formed by drilling a hole through the axis of the drill-shank or
between the axis and external surface of the shank longitudinally through the
drill-shank and bit from end to end or such as would be formed by cutting or
milling a groove along the surface of the drill shank and soldering or otherwise
securing a small tube in it) or by an axial hole through it, which shall be connected
to the actuating fluid of the cylinder and a source of water supply under suitable
pressure. I preferably carry out this feature of my invention in the following
imanner. Axially through the rifle-bar from end to end I drill a hole A¹, and also
axially through the striking end of the piston a similar sized hole A. The hole
through the rifle-bar is counterbored slightly larger through its ratchet head end,
as this end has a little lateral play in its supporting socket in the supplementary
cylinder head 17. A hole is also drilled part way into the back cylinder head
from its inner side which is threaded and a tube 18 is threadedly secured to it.
This tube projects axially through the rifle-bar and piston into a hole 19 drilled
axially through the drill bit 20 from end to end which is larger in diameter than
the end of the tube. The end of the tube is preferably reduced in diameter to
adapt it to extend into the hole through the drill bit for a short distance and is
enough smaller to leave a clear space all around it for the ingress of the actuating
fluid from the cylinder into the hole in the drill shank. The drill bit is illustrated
with a hole of two diameters through it. This is not absolutely necessary.
of even diameter will answer the purpose. It is only essential that the end of
the tube project loosely into it. The drill bit comprises a shank of any of the
customary forms of drill steel in use. At one end 21, it is upset and formed and
sharpened into any one of the several cutting points used for rock drill bits, as
they are made with one, three or four chizel edges. The striking end 22 of the
shank projects through the sleeve 3 into the cylinder and into the reciprocal path
of the piston, which impinges against it at each full stroke. The striking end
is formed into a polygon of preferably five sides for several inches from the end.
At the termination of the polygonal end a portion 23 is preferably turned round
and these two portions at this end are a trifle longer than the length of the
sleeve which is provided with an axial bore 24, that is formed partially round
and partially of a similar polygonal form as the striking end of the drill shank.
The bore of the sleeve is made to fit the polygonal end and round portion of the
striking end of the shank with a loose but snug fit. The drill shank is provided
with a collar 25, at the end of said round portion, which bears against the end
of the sleeve and defines the inward movement of the shank of the drill-bit into
the cylinder. The drill-bit rotates with the sleeve in the cylinder head and is not
clamped or bolted to them and consequently is free to be inserted instantly in
them, or to be withdrawn instantly from them by the operator. The sleeve
does not extend quite to the end of the bore of the cylinder head, a short space
being left in which the collar of the drill bit extends. The sleeve 3 is surrounded
by a collett 26, which also projects into the bore of the cylinder head. This collett
is provided with a thread on its inner end on which is screwed a nut 27. A coiled
expansive spring 28 surrounds the collett and is seated in a counterbore 29 formed
on the cylinder-head, which is adapted to receive it. The expansive spring re-
siliently holds the collett in its normal position in the cylinder head around the
A hole

page_text: rotative sleeve. In order to secure the nut 27 to the collett against unscrewing I
drill a hole 30 through both nut and collett and drive a pin 31 in it, as shown
more clearly in Fig. 10. In order to drive the pin out when wishing to take out
the collett from the cylinder head I provide a hole 32 in the cylinder head in a
position to register over the pin or in line with the pin, in which a smaller pin
may be inserted to drive the pin 31 out of the nut and collett. In order to do
this the cylinder head must be disengaged from the cylinder and the sleeve and
drill bit be first taken out of it. The collett projects forward beyond the face of
the cylinder head far enough to allow a staple pin 33 to be inserted through its
projecting end and straddle the drill bit a short distance in front of the collar of
the drill bit. The distance or space between the collar of the drill-bit and the
staple pin should be about a sixteenth of an inch less than the length of the
striking end of the drill-bit that projects beyond the end of the sleeve into the
cylinder. This clearance between the staple and collar gives the drill bit a little
forward cutting clearance independent of the forward feal of the cylinder, as
when the drill is back against the sleeve, as shown, the drill bit can cut its way
int the rock until its collar strikes the staple, without any forward feeding
movement of the cylinder. The staple pin as shown in Fig. 2 is inserted in
holes 34 that are positioned close to opposite sides of the drill shank and that
extend clear through the collett, and the staple pin projects clear through the
collett and its two prongs extend across and almost touch opposite sides of the
shauk of the drill bit and present a rigid abutment to the collar. The cylinder
should be fed forward by the feed screw just fast enough to keep the collar of the
drill bit substantially back against the end of the sleeve, and with the cutting
point of the drill-bit firmly pressed against the rock as the actuating fluid of the
cylinder always moves the drill forward until it bears against the rock and holds
it there before the piston strikes it, consequently when the piston does strike it
it is resting against the rock and only cuts into it as far as the blow of the piston
drives it into it which is but a trifle if the rock is normally hard and sound, but
if the ground is soft and seamy the drill may be driven so far forward by one blow
that its striking end will be driven inside of the sleeve where the piston cannot
strike it, and if it strikes in a seam the air must be shut off and the drill be backed
and started over. It is to prevent the drill's being driven too far forward and to
prevent its sticking in seams that the staple is used. It is not needed and is never
used where the rock is hard and sound; consequently the staple is positioned to
give the drill bit as much forward movement as possible and still keep its striking
end projecting into the cylinder far enough to allow the piston to strike it and
drive it forward and when the collar of the drill bit is against the staple and the
drill is struck by the piston the collett is also driven forward, but its expansive
spring and the staple returns it and the drill bit back to its normal position, so
that the next blow of the piston will strike the end of the drill bit and the drill
bit if fed forward carefully even if driven from the end of the sleeve against the
staple at every blow of the piston will cut a smooth round hole in any kind of bad
rock. I form the prongs of the staple cither a trifle wider or narrower than the
holes are apart so that it will have to be sprung into them and its resilient tension
when in the holes will assist to hold it in them against displacement, but in order
to provide a positive and simple method of securing the staple in the collett I
preferably form it with the spread of its prongs narrower than the distance apart
of the holes so that it will have to be sprung apart in order to insert it in them.
I then reduce the metal on the inside of each prong to form oppositely opposing
reduced or tapered surfaces which terminate and form a shoulder 35 on the inside
of the prongs and after the staple is pushed into the holes they spring towards each
other after these shoulders pass beyond the lower edge of the holes and the
shoulders overlap the lower edge of the holes as shown in Fig. 2 and form pro-
jecting stops which effectually lock the staple against accidental displacement from
the machine, while at the same time permitting it to be withdrawn from the collett
easily by one hand of the operator, for when the staple is pulled by its yoke portion

page_text: the prongs readily spring apart as the shoulders are slightly beveled and will
easily slide back into the holes. The collett is not attached to the sleeve but is
mounted loosely on it and also fits freely in the cylinder head and can and does
revolve more or less with it. The staple is not intended to be used when drilling
hard sound rock as the cutting drill bits can be changed much quicker when it is
not used and it is not needed only in soft or seamy rock. The rifle-bar, its
pawls 16, of which one is shown, the rear steel buffer ring 36 and rubber buffer
ring 37 are supported in a supplementary cylinder head 17, which is threadedly
secured in a counterbore in the rear end of the cylinder. This supplementary head
contains a chamber in which the said rubber buffer is seated and the steel ring
is placed at its side at the bottom of the counterbore in the end of the cylinder.
The opposite side of the supplementary cylinder head is chambered out to hold the
ratchet head of the rifle-bar and the pawls. The supplementary cylinder head 17
and the rear cylinder head 38 have formed between them an annular recess in
which is fitted loosely a flat ring 39, see Fig. 6, in which I drill three holes 40
which form supporting bearings for the adjacent trunnion 41 of each pawl. These
pawls are used around the ratchet head of the rifle-bar substantially as shown in
Fig. 6, to lock the rifle-bar against rotary movement in one direction and co-
operatively with the rifle-bar they operate to rotate the piston step by step as it
reciprocates in the cylinder. An axial recess is also formed in the rear cylinder
head around the tube 18 to support the hub 42 of the ratchet wheel. The rear
cylinder head 38 in Fig. 1 is screwed into the end of the supplementary cylinder
head and it is necessary in order to screw it on, that the adjacent 'trunnions of the
pawls have a bearing independent of the cylinder head and one that will remain
stationary while the cylinder head is being screwed into place. The rear cylinder
head comprises a flanged head portion with a round body portion a trifle longer
than its diameter which is axially bored out from its outer end to form a valve
chamber. This valve chamber is internally threaded to receive a threaded plug
valve 43 which is provided with a small hand-wheel 44 at its outer end. Its inner
end is pointed to form a plug valve, and the bottom of the valve chamber is beveled
to form a seat for the valve end of the plug. Axially through the valve seat a
hole 45 is drilled from the valve chamber through the cylinder head into the water
tube and the plug valve is adapted to be screwed to and from the valve seat and
to control the passage from the valve chamber to the water tube. A gland 46
is mounted on the plug valve and is threaded to the end of the cylinder head
and packing 47 is placed in the gland to prevent the leakage of water by the
valve. A shoulder 48 is formed by a portion that blends from the flange head
which is larger in diameter than the portion, upon which the gland is mounted and
against this shoulder around the cylinder head is placed a washer 49. The washer
illustrated preferably comprises a flat rubber ring covered with copper. At the
side of the washer 49 I mount to turn freely a coupling 50 which is provided with
an annular chamber 51. Through the shell of the cylinder head a transverse
hole 52 is drilled into the valve chamber and forms a passage from the coupling to
it. At the side of the coupling a washer 53 is placed and a nut 54 is threaded
to the cylinder head at the side of the said washer which is adapted to be screwed
against the washer to compress the coupling and washers against the said shoulder
and each other tight enough to prevent leakage of the water from the coupling.
One side of the coupling is provided with a projecting threaded nipple 55 to which
a hose 55" is secured. The hose connects the coupling with any suitable supply
of water or with any suitable watery liquid under pressure enough to give the
liquid operative power to eject the rock cuttings from the holes. By slightly
loosening the nut 54 the coupling may be turned on the cylinder head as indicated
by the arrows 56 so that the hose of the water supply may be connected to it on
either side of the drilling engine as required.
I thread a cap-screw 57
in the end of the cylinder over the supplementary cylinder head and
drill the cap screw hole into the supplementary head and also drill a second
hole 58, from the adjacent recess of the pawls trunnion to intersect it. These holes

page_text: form an oil passage to the pawls and ratchet. The oil placed in them also works
along the rifle-bar to the rifle-nut 59 which is screwed in the piston-head. This
nut is fluted to slide freely on the flutes 60. of the rifle-bar 14. 61 designates
holes drilled into the cylinder heads to receive a spanner wrench which is the
most convenient wrench to use for loosening or tightening the cylinder heads.
In the front cylinder head I also drill an oil hole 62 and thread a cap screw 63
into it. The oil hole extends to the threaded portion which secured both the
cylinder and head together and around the circumference of the threaded end of
the head a circumferential groove 64 is cut which permits the oil to work to the
cylinder through the threads and along the head to the joint between the collett
and deeve. A similar groove 65 is cut in the threads of the supplementary
cylinder head 17, which registers with the oil hole in which the cap screw 57
is threaded. The valve chest F has a cylindrical bore and at its ends cylinder
heads 66 are threaded to it. These are provided with a wrench receiving hub by
which the heads can be readily screwed on or from the valve chest.
The valve chest is secured to the cylinder by the capscrews 67.
My
invention contemplates the use of any suitable form or type of valve
and any arrangement of valve ports or exhaust ports,
which through
the medium of the expansive fluid will automatically operate the valve and piston
and also the use of any suitable form or type of mechanism for rotating the piston
during its reciprocal movements in the cylinder. The operator of my improved
rock drilling engine is as follows: The actuating fluid may be either com-
pressed air or steam or any other suitable expansive fluid. Compressed air how-
ever is the most exclusively used for running rock drilling engines. It is ad-
mitted through suitable flexible tubing which is threadedly connected to the
ingress holes 68 of the valve chest F to the valve G and operates through the
medium of the co-operating ports 69 in the valve and chest and cylinder to
automatically reciprocate the valve in the chest and the piston in the
cylinder in a well known manner. The piston is turned step by step as it is
reciprocated by sliding spirally on the rifle-bar, which is held against turning in
one direction by its pawls. The piston as it reciprocates slides on the rods 11
and strikes on the end of the drill. The drill bit and drilling engine is or should
be fed by the operator through the medium of the feed screw I, to keep it close
enough to the rock so that the expansive fluid will move it against the rock when it
enters the front end of the cylinder, or should be fed to keep the cutting end of
the drill against the rock and its collar 25 at the same time against the sleeve 3.
The drill and rock receives the full force of the blow of the piston. If the drill
point is too far away from the rock the piston drives the end of the drill into or
out of the sleeve, providing the staple pin is not in place and strikes the end
of the sleeve and the steel and rubber buffer rings take the force of the blow. By
this arrangement I am enabled by proper feeding of the engine and bit to keep
the drill pressed against the rock just before and at the time the piston strikes it.
The recoil of the drill bit from the blow of the piston will move it back a slight
distance from the rock where it can be easily turned step by step through the
medium of the piston, the rifle bar, the rods and the sleeve. When the actuating
fluid rushes into the front end of the cylinder it moves the piston backward
and also moves the drill forward against the rock if the engine is in operative
relation to rock and it rushes into the shank of the drill bit and through it to
its cutting point in a puff-like volume. The water should preferably be under
pressure enough to flow to and through the drilling engine and drill bit without
causing back pressure on the actuating fluid mingling with it. The water supply
pipe or hose is connected to the coupling and the water flows through it into the
valve chamber and from the valve chamber into and through the tube into the
shank of the drill-bit and mixes and commingles with the actuating fluid of the
cylinder as they both flow through the drill bit together. It is not necessary that
the air should be disseminated through the water; it may even combine with it
in the form of independent air piston-like sections as they both flow along. The

page_text: water flows in a steady stream but the size of the stream can be regulated, and
preferably is so regulated by the plug valve and can be reduced to a size that
when mingled with air will result in a spray which is discharged in puffs from the
drill bit in the bottom of the hole immediately after each blow of the piston against
the drill bit and of the drill bit against the rock and allays the dust as well as
drives the rock cuttings from the hole. Some kinds of rock will require more
water than a spray would give but any amount of water can be combined with the
air and may be discharged in a steady stream if necessary, as its volume can be
regulated by the plug valve. My invention contemplates a controllable supply of
water under pressure flowing to the cutting point of the drill bit. In practice I
use a small tank. One of about 18 gallons capacity is large enough for each drill.
I place this tank at a convenient distance from each drill and keep it well supplied
with water and connect it direct with the air compressor or air supply system
and also connect the tank to the drilling engine by hose pipe. The rock cuttings
are a source of great annoyance in drilling rock as they clog the drill bit and
strain the turning mechanism of the drill bit. They also prevent, by packing
between the cutting point of the drill and the rock, the drill's cutting as fast as
it would if they were removed. The cutting edge of a drill will also wear longer
if the hole is kept free from cuttings. All rock drilling engines at present in use
are of the type known as plunger drilling engines. They derive this name from
the fact that the drill bits are removably clamped or bolted or otherwise tightly
secured to an extension of the piston-head called the plunger, which extends
through and beyond the cylinder head and reciprocates through it and is recipro
cated and impinged by the piston against the rock. And it is necessary in a
plunger drill every time the rock cuttings are removed from a hole being drilled
to move the drill bit out of alignment with the hole, in order to insert a spooning
tool to remove them, and afterwards to reset and clamp the drill bit in line with the
hole. By my present invention I am enabled to change the drill-bits very
quickly as they rest loosely in the sleeve. I am also enabled in my new type of
drilling engine first, to save time in changing drill-bits; second, to effect a saving
in the wear and dressing of the drill bit; third, to get a more effective blow on
the drill bit from the piston: fourth, to cut as large a hole and cut it as fast or
faster with fully 50 per cent. less air than a plunger type drilling engine of the
same size cylinder. My new type of drilling engine strikes about 1200 blows
per minute and weighs about one half as much as a plunger type drill of similar
size cylinder.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:-
Claim 1. In a rock drilling engine, the combination with the cylinder and the
piston, of a front cylinder head comprising an integral,, cylindrical member adapted
to be threaded to the end of said cylinder, an axial bore through said head, a
counterbore at its inner end, a sleeve rotatably seated in said bone, buffer rings in
the bottom of said counterbore and a collar or head portion on said sleeve extending
into said counterbore and resting between the buffer rings and the end of said
cylinder, substantially as described.
Claim 2. In a rock drilling engine, the combination with the cylinder, the
piston and the cylinder head, of a rotatable sleeve axially supported in said cylinder
head, having an axial bore, a portion of which is of polygon cross section, with a
drill bit loosely supported in said sleeve and having a polygonal shaped shank
adapted to fit the polygonal bore of said sleeve and having its shank extending
normally beyond the sleeve into said cylinder of the drill, and having a hole,
passage or conduit extending through or along the drill bit from end to end and
adapted to convey a portion of the actuating expansive fluid from the cylinder to
the cutting point of the drill and to the bottom of the hole being drilled, sub-
stantially as described.

page_text: Claim 3. The combination in a rock drilling engine, of the cylinder, the piston,
and the front cylinder head having an axial bore, a counterbore adjacent to its
cylinder end of larger diameter than the bore of said cylinder, a sleeve rotatably
seated in said cylinder head having a collar portion on its inner end extending
into said counterbore and of larger diameter than the bore of said cylinder, a
rubber buffer ring and a steel buffer ring surrounding said sleeve between the
collar portion and the bottom of said counterbore and having two or more rous
secured at diametrically opposite points in the collar portion, with said piston
head having holes therein adapted to fit freely said rods and adapted to reciprocate
on said rods, substantially as described.
Claim 4. The combination with the cylinder and the piston, of the front cylinder
head, the sleeve, the rods the free holes in the piston in which the rods extend and a
bushing at the entrance of said holes adapted to fit slidably the said rods, sub-
stantially as described.
Claim 5. The combination with the cylinder and the piston, of the front cylinder
head, the sleeve, the buffer rings, the rods secured to said sleeve, the holes in said
piston head, the bushings at the entrance of said holes and the drill bit adapted
to be operatively supported by said sleeve and having a passage or conduit from
end to end adapted to convey a portion of the actuating expansive fluid from the
cylinder to the cutting point of the drill and to the bottom of the hole being
drilled, substantially as described.
Claim 6. The combination with the cylinder and the piston, of the front qylinder
head, a sleeve rotatably supported axially therein, a drill bit operatively supported
by said sleeve and means connected with the said piston for rotating or turning
said sleeve and drill bit step by step, substantially as described.
Claim 7. The combination with the cylinder, the piston and the front cylinder
head, of a drill bit, adapted to be operatively held and supported loosely in said
cylinder head so as to be withdrawn, therefrom and inserted therein instantly at
will, and adapted to extend into the reciprocal path of said piston and be impinged
by it in its reciprocal movements in the said cylinder and having a passage ex-
tending through it, from one end to the other adapted to convey a portion of the
actuating expansive fluid used to operate the piston from the front end of the
cylinder to the cutting point of the said drill bit and means for rotating or turning
said drill bit step by step at each full stroke of said piston,, substantially as
described.
Claim S. The combination with the cylinder, the piston, the front cylinder head
and the sleeve freely supported by said cylinder head and having an axial perfora-
tion round in cross-section for a portion of its length and of polygonal shape for
the rest of its length with a drill bit having a shank adapted to fit both portions
of the hole in said sleeve loosely, and extending through said sleeve into said
cylinder into the reciprocal path of said piston, a counterbore in the outer end of
said cylinder head, a collar or projection on said drill bit normally resting in
said counterbore and adapted to define the inward movement and the position of
the end of the drill-bit's shank relative to the said piston, means for rotating said
drill bit and sleeve step by step, and an axially arranged hole extending through
said drill bit from end to end and adapted to convey a portion of the actuating
expansive fluid from the cylinder to the cutting point of said drill bit, substantially
as described.
Claim 9. The combination with the cylinder, the piston, the front cylinder head
and the sleeve, of a drill bit adapted to be operatively supported by said sleeve and
having a pentagon shaped shank and a round portion adjacent to said pentagon
end, a collar or projection adjacent to said round portion and an axial perforation
through said drill bit and means for rotating said drill bit step by step, sub-
stantially as described.
Claim 10. The combination with the cylinder, the piston the cylinder-head and the
sleeve, having a square or polygonal shaped, axially arranged aperture, with a
drill-bit of any form of cross-section, having a square or polygonal shaped striking

page_text: end adapted to fit freely the polygonal aperture in, said sleeve and arranged to be
operatively impinged and intermittently rotated by said piston, a collar or pro-
jecting portion adjacent to said drill-point's striking end adapted to normally rest
against the outer end of said cylinder-head, and a passage from the striking end of
said drill bit to its cutting point adapted to convey a portion of the piston's actuat-
ing fluid from said cylinder to the cutting point of said drill-bit and to the bottom.
of the hole being drilled, substantially as described.
Claim 11. In a rock drill bit, a drill shank of any merchantable form of cross-
section having a cutting point of any desired common form, a polygonal shaped
striking end, a collar, adjacent to said end and an axial hole from end to end
throughout its length, or a closed passage attached to or arranged to form a part
of said drill bit extending from its striking end to its cutting point, substantially
as described.
Claim 12. The combination with the cylinder, the piston and the front cylinder
head, of a drill-bit resting freely and loosely and not in any way clampingly
secured or fastened to the cylinder head but operatively supported in a substan-
tially fixed position relative to the reciprocal movements of said piston and arranged
and adapted to be struck intermittently and successively by said piston,
means for rotating said drill-bit step by step and means for conveying a
portion of the piston's actuating fluid from the cylinder to the drill-bit's cutting.
point, substantially as described.
Claim 13. A rock cutting drill for rock drilling engines, comprising a bar of
drilled steel of any form of cross section containing an axial hole through it from
end to end and a collar or projection or shoulder adjacent to or at a short distance
from its striking end substantially as described.
Claim 14. A rock drilling engine having a rock cutting drill loosely positioned
and supported in and to the drilling engine and arranged to be impinged upon
one end by a reciprocal movement of the piston, and arranged and adapted to
convey a portion of the piston's actuating Huid directly from the cylinder into
and through said cutting drill to its cutting point and to the bottom of the hole
being drilled, whereby said actuating fluid is used to expel the rock cuttings from
the hole being drilled, substantially as described.
Claim 15. A rock drilling engine having a rock cutting drill loosely positioned
and supported in the drilling engine and arranged to be impinged upon one end
by a reciprocal movement of the piston, an axial hole through said rock cutting
drill from end to end arranged and adapted to convey a portion of the piston's
actuating fluid directly from the cylinder to its cutting point to blow out from
the hole being drilled the rock cuttings, and said drill arranged and adapted
to be moved by the expansive fluid against the rock after each recoil from the rock,
after each blow of the piston, substantially as described.
Claim 16. A rock drilling engine for expelling the rock cuttings from holes
while drilling them, consisting of an operative drilling engine having rock cutting
drills arranged and adapted to extend into the cylinder of the drilling engine
and to be struck and actuated to cut rock by the reciprocative movements of the
piston impinging against its inner end and in which the cutting drills have an
axial hole through them from end to end, and the piston's actuating fluid has at
all times, free direct and unobstructed passage from the cylinder to the cutting
point of the drill and to the atmosphere and to the bottom of the hole being
drilled, substantially as described.
Claim 17. A rock drilling engine having a rock cutting drill arranged to be
struck by the reciprocal movements of the piston and provided with a collar, pro-
jection, or shoulder adjacent to its striking end, adapted to form an abutment or
rest, against the front part of the drilling engine and define the cutting drill's
operative relative to the engine's piston and a passage axially through said cutting
drill arranged to conduct a portion of the piston's actuating fluid directly from the
cylinder to the cutting point of said rock cutting drill, substantially as described.
Claim 18. A rock drilling engine provided with a drill bit arranged to project

page_text: into the cylinder of the drilling engine and arranged to be operatively struck
upon its end by the reciprocal movements of the engine's piston and containing a
passage or conduit from said engine's cylinder to or adjacent to said drill bit's
cutting point and a water passage or tube or conduit and a suitable water supply
through said drilling engine to said passage in said drill bit whereby a commingled
supply of the cylinder's actuating fluid and water is conveyed from said drilling
engine through said drill bit to its cutting point and to the bottom of holes in
rock while drilling them, substantially as described.
Claim 19. A rock drilling engine comprising a suitable cylinder, a reciprocative
piston, a suitable controlling valve and a suitable feeding mechanism and drill
bit arranged to project into said cylinder into the reciprocal path of said piston
and arranged and adapted to be struck directly on their cylinder invading ends
by the reciprocal movements of said piston, and containing a passage or conduit
for the actuating fluid of said rock drilling engine opening into or communicating
with said engine's cylinder and extending through said drill bits to or adjacent
to their cutting points, a water conveying tube or conduit and a water supply
connecting with the said passage or conduit in said drill bits and a combined stream
of water and the cylinder's actuating fluid flowing through said drill bits to their
cutting points and to the bottom of holes while drilling them, whereby a combined
stream of commingled actuating fluid and water is forced to the cutting points
of said drill bits while drilling rock and the rock cuttings are thereby rejected,
substantially as described.
Claim 20. In a drilling engine, the combination, with the cylinder and the
piston, of a drill bit containing an axial hole from end to end and extending into
the cylinder and open to the engine's actuating fluid, an axial bore through said
piston, and a tube in said bore projecting into the hole in said drill bit, sub-
stantially as described.
Claim 21. The combination in a rock drilling engine, of the cylinder, the piston,
the cylinder heads, the sleeve and the hollow drill with a liquid or water conveying
tube through said piston connected with said hollow drill and a passage from
said cylinder adapted to allow the oylinder's actuating fluid to flow into said
hollow drill, whereby a combined stream of liquid and actuating fluid is caused
to flow through said drill bit to the bottoms of holes while drilling them, and
mcans including a valve for controlling the volume and pressure of said liquid and
actuating fluid stream, substantially as described.
Claim 22. The combination with the cylinder, the piston, the front cylinder head,
the sleeve and the roals projecting from said sleeve into said piston with a hollow
bit keyed loosely to said sleeve and arranged to be instantly withdrawn from or
inserted in said sleeve and provided with means for defining its operative position,
in said sleeve and to said cylinder and piston and with a fixed tube projecting from
the rear end of said cylinder freely through said piston and extending into said
drill bit, substantially as described.
Claim 23. The combination with the cylinder and the piston of a hollow drill
bit projecting into said cylinder into the reciprocating path of the piston and
arranged to convey a portion of the piston's actuating fluid to the bottom of holes
while drilling them with a water tube projecting into said drill bit for supplying
water under pressure and mingling it with the actuating fluid of said drill bit
and discharging into the bottom of holes while drilling them in a combined stream
of actuating fluid and water, substantially as described.
Claim 24. In a drilling engine for expelling rock cuttings from holes while
drilling them and for laying the rock dust, a substantially combined mixed or
commingled operative supply of any suitable watery liquid and an operative
portion of the engine's actuating fluid discharged steadily or intermittently during
operative rock drilling or at each stroke of the piston, or at suitable intervals in any
suitable operative form such as a spray or jet, or as a stream into the bottoms of
holes in rock while drilling them, substantially as described..
Claim 25. The combination with the cylinder and the piston, of the front, the

page_text: rear, and the supplementary cylinder heads, a hollow drill bit projecting into said
cylinder in the path of the piston and a water inlet tube secured to said rear
cylinder head and projecting through said piston into said drill bit, substantially
as described.
Claim 26. The combination with the piston, the drill bit, the supplementary
cylinder head, the rifle-bar and the rear cylinder head having a water inlet tube
secured thereto and projecting therefrom loosely through the axial center of said
rifle bar and said piston into the striking end of said drill bit, substantially as
described.
Claim 27. The combination with the drill bit, the piston and the rifle-bar, axial
holes through said rifle bar and piston, a water inlet tube projecting loosely
through said axial holes into said drill bit adapted to conduct a stream of water
under pressure through said tubes and drill bit, and a valve for controlling the
flow of said water, substantially as described.
Claim 28. The combination in a rock drilling engine, of a piston having an
axial bore, a rifle-bar also having an axial bone, a cylinder head having a tube
projecting through said rifle-bar and piston, a water passage to said tube, a valve
adjacent to said tube for controlling said passage, means for mingling said water
with a portion of the engine's actuating fluid and means for conducting said
actuating fluid and water in a combined stream to the bottom of holes in rock
while drilling them, substantially as described.
Claim 29. The combination with the hollow drill bit, of the sleeve, the cylinder,
the piston, the rifle-bar and the rear cylinder head having a water inlet tube pro-
jecting through said rifle-bar and piston into said drill-bit, and a passage around
said tube from said cylinder into said drill bit, substantially as described.
Claim 30. The combination, with the cylinder and the piston, of a hollow drill
bit mounted to be turned step by step by said piston, a water inlet tube projecting
into said drill bit, and a passage from said cylinder into said drill bit, substantially
as described.
Claim 31. The combination with the cylinder, the piston, the cylinder head and
the sleeve, of a hollow drill bit projecting into said cylinder and adapted to convey
a portion of the cylinder's actuating fluid to its cutting point; of a conduit adapted
to convey a stream of water under pressure to said drill point, a rear cylinder head,
a passage in said cylinder head for said water, a valve adapted to control the
admission and volume of said water, and a water inlet coupling adapted to connect
with a source of water supply on either side of said cylinder, substantially as
described.
Claim 32. The combination with the piston having an axial hole, the drill bit,
the rifle-bar having an axial hole and the back cylinder head carrying a water
inlet tube projecting through the axial bores of said rifle-bar and piston, with a
water inlet coupling rotatably mounted on said cylinder head, a passage from said
coupling to said tube and means including a nut and thread for packing said
coupling against leakage, substantially as described.
Claim 33. The combination with the piston and the hollow drill bit, of the
back cylinder head, the water inlet tube projecting therefrom through said piston
and into said drill bit, a passage through said cylinder head for the admittance of
water under pressure to said tube and drill bit, a valve controlling said passage
and a suitable packing device for said valve, substantially as described.
Claim 34. The combination of the hollow drill bit, the piston, the rifle-bar, and
the back cylinder head, with a tube projecting loosely through bores in said rifle
bar and piston and with a water inlet coupling having a hose or pipe connecting
nipple, and a passage from said coupling to said tube, substantially as described.
Claim 35. The combination with the back cylinder head, of the rotatable water
coupling mounted thereon, a shoulder or abutment adjacent to said coupling, a
washer between said coupling and said shoulder, a second washer on, the opposite
side of said coupling, and a nut threaded to said cylinder head adapted to tighten

page_text: said washers and coupling against said shoulder and thereby pack said coupling
against leakage, substantially as described.
Claim 36. The combination of the supplementary cylinder head, the rear cylinder
head secured thereto, the water inlet tube, the riffe-bar revoluble on said tube, the
piston arranged to reciprocate and turn on said tube, and the hollow. drill bit
surrounding the discharging end of said tube, substantially as described.
Claim 37. The combination with the back cylinder head of the water inlet
coupling rotatively mounted thereon, the washer at its sides and the tightening
nut, substantially as described.
Claim 38. The combination with the cylinder, of the piston, the hollow drill
bit, the rifle bar and the water inlet tube projecting through said rifle bar and
piston into said drill bit, with the back cylinder head, the water inlet passage
therein the water inlet coupling and the valve for controlling said water inlet
passage, substantially as described.
Claim 39. The combination of the cylinder, the piston the rifle-bar and the
pawls, with the supplementary cylinder head and back cylinder head, the pawl
trunnion supporting ring; a water inlet tube, a threaded hole in said cylinder and
into said supplementary cylinder-head; a cap-screw in said threaded hole and
an oil-hole leading from said cap-screw hole to said pawls and rifle-bar, sub-
stantially as described.
Claim 40. The combination in an operative rock drilling engine of a drill bit
having a passage to its cutting point, a water or liquid conduit, through said
engine to said drill bit and means for introducing a portion of the engine's actuating
fluid into said water conduit or to said drill bit, and for delivering a combined
stream or jet of actuating fluid and water from said drilling engine and drill bit
to the bottom of holes while drilling them, substantially as described.
Claim 41. The combination in a rock drilling engine of the cylinder and the
piston with the front cylinder head having a rotative sleeve arranged to be turned
step by step by said piston, a drill bit operatively supported by said sleeve and
arranged to conduct a portion of the cylinder's actuating fluid and a stream of
water from the engine's cylinder to its cutting point, a collett surrounding said
sleeve, an expansive spring arranged to resiliently hold said collett in normal
operative position, an abutment collar on said drill bit arranged and adapted to
receive and define the backward thrust of said drill bit and a removable pin in
said collett arranged to be engaged by said abutment collar, substantially as
described.
Claim 42. The combination in a rock drilling engine, of the cylinder, the piston
and the front cylinder head with the sleeve supported therein, a drill bit opera-
tively supported by said sleeve; a collett surrounding said sleeve, means for holding
said collett resiliently in operative position in said cylinder relative to said drill
bit and sleeve and a suitable pin or key removably arranged in said collett to
operatively confine said drill bit to said sleeve, substantially as described.
a
drill bit
Claim 43. The combination in a rock drilling engine of the cylinder, the piston,
the front and rear cylinder heads: the rifle-bar rotating mechanism and the feed
mechanism, with a water conveying tube projecting from the rear cylinder head
through said rifle-bar and piston a drill-holding sleeve, revolubly mounted
in said cylinder head; axial bore through said sleeve,
an
operatively supported by said sleeve and arranged to be operatively
rotated step by step by said piston and sleeve, and provided with a conduit or
passage.communicating with said cylinder and with a discharge end of said water
conveying tube and arranged and adapted to convey a combined and commingled
stream of water and actuating fluid to the cutting point of said drill bit, and having
said drill bit project into the reciprocal path of said piston and arranged to be
impinged by said piston, a collett loosely mounted on said sleeve, a spring arranged
to hold said collett in operative relation to said sleeve and drill bit, an abutment
on said drill bit and a suitable pin or key removably secured in said collett and
arranged and adapted to be engaged by the abutment of said drill-bit, whereby

page_text: said drill bit is held in said sleeve against-accidental displacement, substantially
as described.
Claim 44. The combination of the cylinder, the front cylinder-head and the
pistou, with the sleeve having rods projecting into suitable apertures adapted to
receive them into said piston, the collett surrounding said sleeve, the nut threaded
to its end, the expansive spring arranged between said nut and a shoulder of said
cylinder head, the staple pin and the drill bit operatively supported in said cylinder
head by said sleeve, collett and staple pin, substantially as described.
Claim 45. The combination in a rock drilling engine, of the cylinder, the piston
and the front cylinder head containing a drill holding sleeve arranged to be
operatively rotated in said cylinder head by said piston, a drill-bit operatively
supported by said sleeve, a collet surrounding said sleeve, means for hoiding said
collett in resilient operative relation on said sleeve and having said collett arranged
and adapted to hold said drill bit within striking distance of saad piston, sub-
stantially as described.
Claim 46. The combination of the cylinder, the piston and the cylinder head,
with the sleeve and drill bit, a collett loosely surrounding said sleeve and arranged
and adapted to resiliently reciprocate axially in said sleeve, a thrust abutment on
said drill bit and a slip pin in said collett arranged to be engaged by said thrust
abutment, substantially as described.
Claim 47. The combination of the cylinder and the piston with the drill holding
sleeve, the rods extending from the sleeve into said piston and the collett and
staple-pin, substantially as described.
Claim 48. The combination with the cylinder, the piston and the front cylinder
head, of the drill holding sleeve; the rods secured thereto and extending into said
piston, the hollow drill bit provided with a thrust abutment, a collett surrounding
said sleeve and arranged to resiliently receive the concussion of said drill bit and
the staple pin, arranged and adapted to be engaged by said thrust abutment and
to automatically lock itself against accidental displacement from said collett, sub-
stantially as described.
Claim 49. The combination with the cylinder, the piston, the rifle bar and
pawls, the valved water conveying tube, the water inlet coupling, the cylinder head
with the drill holding sleeve arranged to be rotated by said piston, the hollow
drill bit supported by said sleeve, the collett and its staple pin, substantially as
described.
Claim 50. The combination with the cylinder and the piston of the front cylinder
head, the drill holding sleeve, the drill-bit having a thrust abutment collar and
with a collett loosely mounted on said drill holding sleeve in said cylinder head
and arranged and adapted to confine said drill bit to said sleeve against inoperative
displacement out of striking distance of said piston, substantially as described.
Claim 51. The combination in a rock drilling engine of an operative cylinder,
an operative valve mechanism, a piston arranged to rotate step by step as it re-
ciprocates in said cylinder and a suitable feed mechanism, with a drill bit loosely
and unclampably supported operatively by said drilling engine and arranged to be
impinged against by said piston, and adapted to be rotated step by step by said
piston and containing a passage throughout its length communicating with said
cylinder, a valve water conveying tube extending through said piston and com-
municating with the passage in said drill bit, and means including a thrust abut-
ment on said drill-bit for confining said drill bit within operative striking distance
of said piston, substantially as described.
}
Dated this un day of May 10
JOHN GEORGE LEYNER.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.