Stone by Means of Compressed Air or Steam.
Year: 1886

page_text: Stone by Means of Compressed Air or Steam.
I THOMAS MAYNE trading as Le Gros, Mayne, Leaver and Coy., of N° 60 Queen
Victoria Street, London, E.C. in the County of Middlesex, Mining Engineer, do
hereby declare the nature of my invention for IMPROVEMENTS IN APPARATUS FOR
BORING AND DRILLING ROCK OR STONE BY MEANS OF COMPRESSED AIR OR STEAM,
which Invention has been communicated to me from abroad by Charles William
Potter of New York, U.S.A., 'Civil Engineer, and in what manner the same is to be
performed, to be particularly 'described and ascertained in and by the following
statement and accompanying sheet of drawings:
:-
The improvements connected with rock drilling machines or apparatus com-
prising my said Invention have reference to that class of said devices which have
an air, or steam cylinder, with drill attached to one end of the piston rod. Said
improvements may be distinguished under three heads, as hereinafter described,
reference also being had to the accompanying sheets of drawings, illustrative of my
said Invention, in the case where steam is employed, as the motive power, that
is to say:
The first head or feature of my said Invention consists in the particular arrange-
ment which I adopt of the valve, piston, and live steam (in cases where steam is
employed, as the motive power) chest relatively to each other, in such manner that
the ends of the valve as the latter moves, project ultimately into a live steam
chest within the body of the central part of the cylinder and in the pathway of
the piston, whereby the valve is moved directly by the piston, without necessitating
the employment of any intervening intermediate parts.
This first feature of my said Invention is illustrated in the accompanying
drawings at Figs. 1. 2 and 3.
Figure 1 is a vertical sectional view, shewing the cylinder, valve, steam chest
and steam chest cover which latter contains the valve vent, and steam and exhaust
passages.

page_text: Figure 2 is an elevation of the cylinder and section through the steam chest
cover on line A. B. Fig. 1.
Figure 3 is a transverse section of the same taken on line C. D. Fig. 2.
Referring to the Figures, F is the cylinder which is bored out to receive the
piston D which is a straight cylindrical piece having packing rings near each end,
and which is turned down to a smaller diameter near the centre so as to produce
inclined shoulders g and g¹ to move the valve, and also to give room round it to
form the steam chest C. S. Fig. 3, is the steam opening for admitting steam to the
steam chest and is cast on the body of the cylinder. E is the exhaust passage to
allow the steam after being used to escape, and is cast in the steam chest cover.
fand f¹ are the steam passages for admitting steam to and from the opposite ends
of the piston D. The termination of these passages in the steam chest cover form
the seat of the valve A, the circle of which is preferably struck from a point at, or
near the centre of the cylinder.
The position in the drawings shews the piston D, travelling in the direction
indicated by the arrow with the steam pressure in the upper end W¹, of the
cylinder, and the lower end W, open to the atmosphere through the exhaust E.
It will be seen that the travel of the piston in this direction is just commenced
and that the inclined shoulder g will be brought or come into connection with the
end of the valve A which by a continued movement of the piston in the same
direction must be moved into a position to reverse the direction of the steam, and
throw the opposite end a, of the valve into that part of the steain chest within the
cylinder, to be in turn moved by the inclined shoulder g¹, of the piston, as it
moves in. the opposite direction, thus bringing the parts into their first position,
which change of position must occur as long as the machine is supplied with
steam, or air, as the case may be..
With a view to reducing the cost of construction and of rendering more reliable
the action of the chuck employed in connection with a rock drilling machine
such as herein before referred to, I employ for said purpose the device illustrated at
Figures 5 and 6, referring to which it will be seen that a hole is bored in the
head A, at the end of the piston rod B, the size of said hole being adapted to
receive the shank C of the tool. Two holes are bored transversely at the sides of
the tool for the reception of the staple-formed clamping bolt D, the nuts E of which
press against one side of the head A, which has a flat surface at this part. The
exterior surface of the chucking block G is turned off or shaped cylindrically, and I
bore in the side of the head A, a cylindrical hole into which the block G fits. By
this means I am enabled to prevent any looseness or motion of the block G, in the
bead, and the parts cannot become battered or loose by use. The edges of the
block G, are notched where the screw staples pass the same. By this mode of
construction, I am enabled to make a hardened steel chucking block, with two
similar faces, either one of which can be used, and the said block being within a
recess, it cannot become detached or lost, as the screw staple only requires to be
loosened; the entire work of construction therefore can be done by machinery,
hence the cost is greatly lessened.
Under the second head or feature of my Invention is comprised the means
which I adopt, as illustrated at Figures 1 and 2, with a view to allow of the
piston, piston rod, and tool holder, all being one forging, and to secure a cylinder
head, inade up in two parts in such manner as to be steam tight, and receive a
packing gland. I likewise so construct the parts that the risk of injury arising
from the piston striking the inner end of the head, is reduced to a minimum, and
I provide means for revolving the piston, rod and drill, or tool progressively and
automatically in a very reliable manner. The front head d of the cylinder F, is
made to fit the cylinder, and has a conical extension piece made at the angle
shewn. Around this head is the conical ring b, having ears at opposite sides for
tie bolts e passing to the head or cap i at the other end of the cylinder, and which
last referred to cap is preferably conical. Its interior surface is similar to the
ring b, and fits over the back head j, the interior of which head is also conical

page_text: Now, on a conical metal plug being driven into a conical metal ring it will not
wedge therein, when the taper is as shewn in the drawing-I avail myself of this
feature to prevent injury to the piston head or bolts, by the concussion of the
piston against the inner surface of the head; for there will be a slight yielding
when the tapering plug of the head is forced into the tapering ring, and there will
not be so much injury to the bolts or other parts-The cylinder front head d, is to
be bored out to receive a packing into which is screwed the gland h. The back
head is furnished with a cylindrical sleeve k, through which passes the nut 1, of
the feed screw.
A flange m is provided at one end and a lock nut n, at the other,.
with a view to prevent the rotation of the nut in the sleeve.
The
Referring more particularly to Figures 1, 9 and 10. With a view to cause the
steam pressure to hold the disc p' when the piston is moving in one direction, or to
allow it to turn when moving the other way, and to ensure this being accomplished
satisfactorily I add an independent suction disc o (Fig. 9.) between the disc p,
and the head, of the cylinder, and I provide a cross key 5, or pin upon the disc o
entering a similar recess in the disc p, so that the rotator q, disc p, and plate o,
will all revolve together; but the disc or plate o is not vibrated or moved end wise
of the cylinder by the piston sliding backwards and forwards upon the rotator q,
hence the disc o will always rest against the inner surface of the head j by the
pressure of the steam acting through the circular holes in the disc of the rotator
Fig. 10. I provide a hole 6 (Fig. 1) through the head, and countersink the inner
surface of the head, so that the disc o, bears against a ring shaped surface.
opening 6 prevents the accumulation of steam pressure between the disc o and the
head. The steam pressure when acting against the disc o, will be found in practice,
to hold the same with sufficient force to prevent its turning; and the key 5,
prevents the rotator turning as the piston moves along over the rotator; hence the
piston and tool are partially revolved; but when the pressure of steam against the
disc o is relieved, and the piston is being moved the other way, the disc o, will
turn freely with the rotator. The nut r, Fig. 1 of the rotator is screwed into a
cylindrical recess within the piston; it is shorter than the depth of the recess, and
the base of the rotator at its junction with the disc is slightly rounded and enlarged
so that it will serve to enlarge the upper end of the nut r, and wedge it firmly.
into its cylinder, in case it should partly unscrew, so that the said enlarged part of
the rotator comes in contact with said nut. The rotator is also strengthened by
the enlargement of its base.
The third head or feature of my said Invention has reference to the special
devices which I employ as comprising the tripod and hub of a rock drilling machine
or apparatus such as herein before referred to and described. Said devices being
illustrated by an elevational view partly in section at Figure 4. The two front
legs A, B, and the rear leg C, are each made with a tube, with an extension rod
therein which may be set at any desired length and clamped by any suitable
means. In practice it will be found advantageous usually to place movable weights
upon the legs, in order to keep the instrument from being affected by, or under, the
reciprocatory action of the drill. The upper end of each tube is forged solid, with
a bolt or bar inserted into the tube, the exterior being tapering or conical and
provided with a screw and nut at the end; each socket is tapering so that the ends
of the tubular legs fit firmly therein, and the concussion will not produce any
looseness of the leg in its socket, as the parts wedge tightly together, and the nut
is set up from time to time.
The cylinder of the drill (Figure 1) is provided with a hub x around the periphery
of which is a groove, and the split band H, (Figure 4) is adapted to fit around
said hub x. The bolt h still referring to Figure 4 is employed to clamp the
split band to the hub, and is passed across so as to enter the groove above mentioned
at one side, thereby preventing the separation of the ring from the hub; at
the same time allowing of the latter being turned round in the ring or band H.
At the sides of the split ring or band H there are hubs h¹, with circular conical
recesses, for the reception of similar shaped projections k, upon the link pieces k.. The

page_text: At
bolt h, passes through these link pieces, and by screwing same up, the link pieces k
are clamped in a thoroughly firm and reliable manner to the split band H. Thus,
the bolt h, performs the threefold duty of clamping the band to the cylinder,
preventing the band separating from the cylinder, and of clamping the links.
the ends of the links k, there is a bolt m, passing through said links, and through
the stock n, of the socket n¹, which receives the upper end of the back leg C.-The
ends of the stock n, may enter tapering recesses in the faces of the links k, so as to
make a very firm connection for the back leg when the bolt m, is tightened up..
Each link, is provided with a cylindrical projection or trunnion at one side,
around the bolt h, and this is grooved peripherally.. The sockets o and of of the
front legs, are provided with split bands p, p¹ adapted to fit around the respective
trunnions; the clamp screws r, r, of the respective split bands, pass at one side
into the peripheral groove aforesaid, so as to prevent the parts separating, and by
tightening such bolts, after the respective legs have been moved to their places, the
split bands will effectually clamp the trunnions.
Referring to the modification illustrated at Figures 7 and 8, my object is to
prevent the parts named hereunder wearing in such a manner, as to become
inoperative to hold the rifle bar or. shaft with sufficient force to turn the piston,
rod, and drill when moving in one direction, and to loosen the rifle bar, so that it
may be free to turn, by the action of the piston, when moving in the other direc-
tion; also to allow the clutch itself to turn when an undue torsion is applied to
the drill, and thereby prevent injury to any of the parts, by allowing them to turn
and yield when the drill may give a powerful concussive blow: Figure 7; is a
vertical section of part of the rock drill cylinder and head, and elevation of the
rifle bar. Figure 8 is a vertical section of the cams and holder arranged in a
modified form.
The cylinder, feeding screw, and piston are of ordinary character, and the rifle
or feed bar passes into the piston as usual. The cylinder head a, is adapted to
receive the cap b, and the two are secured by the bolts c, or by the bolts of the
cylinder. This head and cap are recessed to receive the cam head d, of rifle bar e,
and the cam clamps f. The cams are two or three in number, and assume the
form preferentially of sections of volutes, extending outwardly-In Figure 8, they
are shewn as concentric inclines-The cams act against the clamp-pieces f. If they
are volute cams; there must be a clamp for' each cam; but with the concentric
inclines, Figure 8, the inclines or cams act against similar inclined or cam, surfaces
upon the clamps. If the exterior surfaces of clamps f Fig. 7; are cylindrical, or if
the upper surface of clamp Fig. 8. is' flat and without the annular rib aforesaid, the
device is liable to be not fully operative, because the action of the cains upon the
clamps will either revolve the clamps in one or other direction, or else the cams
may wedge the clamps comparatively iminovably, so, that the parts will not operate
promptly, or will be injured.
I find that the power required to hold the clamps. from rotating must be
Bufficiently great to prevent them turning under the ordinary. outward pressure of
the cams, so that the clamps will remain stationary, and hold the cams, when the
parts are being turned in one direction, and will free themselves, and turn freely in
the other direction. To accomplish this object I proportion the inclined surfaces
of the cams, so as to hold; with the required power; and I prefer to make use of a
wedge-acting holder for the clamps-When the clamp is in the form of a disc,
Figure 8, there is a V, or wedge groove g, and a similar rib h, the rib being upon
When the
the head or cap'i. (Fig. 8) and the groove in the clamp, or the reverse.
clamps assume the form shewn in Figure 7: the holder' is devised, so as to present
either a single or double conical edge to the clamp, and a similar shaped recess to
the heads. In both cases, the action of the cams is to force the clamps into the
wedge-acting holders; and wedge the same with sufficient firmness, to hold the
clamp, and so to ensure that the cams may separate upon the reverse movement
in consequence of the clamps remaining stationary, as the cams may turn away
from them, thus releasing the parts and allowing the reverse movement before
'

page_text: named: but, the parts will yield and turn under an unusual strain without injury
or breakage.
At j, Fig. 7. is a screw plug to an oil hole, and at k, there is a hole in the cam
with branches to supply the lubricant to the surfaces of the cams.
The holder that applies friction to the surfaces of the clamps, or clamp, is of a
greater diameter than the cams upon the rifle bars, hence there is a greater friction
against the exterior of the clamps to hold them than there is of the cams, as they
act against the clamps to move them in either direction, and then by proportioning
the angles or inclinations of the contact surfaces, the clamps are held with sufficient
frictional force to cause the rotation of the piston and drill, as the piston moves
forward over the rifle bar; but unusual strain in this direction will cause the clamps
to slide upon their contact surfaces by the rotative power of the piston and drill.
In the other direction, the cams turn away from the clamps, while the latter are
held by super-friction, and then all the parts rotate freely.
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
:-
First The valvular arrangement described and shewn in Figures 1. 2. and 3
of the accompanying drawings, the essential features of which comprise a valve
provided with steam passages, and sliding end wise in the arc of a circle, in com-
bination with inclines upon the piston for communicating the end movement to
the valve substantially as herein set forth.
Second-The special devices which I employ as comprising the tripod and hub
of a rock drilling machine or apparatus according to my Invention, substantially
as herein described and illustrated at Figure 4 of the accompanying drawings.
Third In rock drilling machines or apparatus, the means which I adopt with a
view to reducing the cost of construction, and rendering the action more reliable of
the chucking arrangement, substantially as herein set forth and shewn at Figures 5,
and 6, of the accompanying drawings.
·
Fourth-The means which I adopt, as herein before described, in reference to
Figures 7. and 8. whereby the wear and tear of the parts herein before referred to,
is effectively reduced and injury from concussive blows prevented substantially as
herein set forth.