AN IMPROVED MACHINE FOR DRILLING OR BORING ROCKS AND OTHER HARD SUBSTANCES
Year: 1877

page_text: LETTERS PATENT to Thomas Brown Jordan, of the Firm of Thomas B
Jordan & Son, Engineers and Contractors, Queen Victoria Street, in the City
of London, for the Invention of "AN IMPROVED MACHINE FOR DRILLING OR
BORING ROCKS AND OTHER HARD SUBSTANCES "
Sealed the 6th April 1877, and dated the 2nd February 1877.
PROVISIONAL SPECIFICATION left by the said Thomas Brown Jordan at
the Office of the Commissioners of Patents on the 2nd February 1877
THOMAS BROWN JORDAN, of the Firm of Thomas B Jordan & Son, Engineers
and Contractors, Queen Victoria Street, in the City of London "AN IMPROVED
MACHINE FOR DRILLING OR BORING ROCKS AND OTHER Hard SubstanCES."
My Invention relates to an improved machine for drilling or boring rocks or
other hard substances
>
The principal feature of novelty of the said machine is the employment therein
of pneumatic pressure, as hercin-after set forth, and I therefore call the said machine
the pneumatic lock drill
The said Invention also relates to improvements in the construction and arrange-
ment of parts of the machine, as herein-after described
My improved machine has a close air cylinder fitted with a piston, which is
drawn up or toward the top of the said cylinder by a cam or cams fixed on a shaft,
which may be rotated by manual power applied to a winch handle, or may be
connected by suitable gearing with any suitable motor The said cams act on the
piston rod to raise or draw back the same and the drill through the medium of a
lifting block, herein-after described
The said piston is packed with cup leather, or in any other suitable manner, so
that it forms an air-tight partition between the portions or volumes of air on its
two sides The piston rod is tubular, and passes through stuffing or packing boxes
at both ends of the said cylinder By this combination of parts I obtain a cylinder
full of an at the ordinary pressure of the atmosphere, and the said cylinder may
contain some au on both sides of the piston I dull a small hole, or any desired
number of such holes, through the body of the piston, and through the top cover of

page_text: the cylinder. These holes in the piston and cover are fitted with valves, acting in
such a manner that when the piston is depressed to the bottom of the said cylinder
all the air will pass to the top or upper portion of the cylinder, which will then by
the action of the said valves be full of air
If the said piston should now be drawn up by the rotation of the said cam or
cams the air thus contained in the cylinder above the piston will be compressed in
the space between the upper side of the latter and the top cover of the cylinder
This space may bear any desired proportion to the length of the piston's stroke;
and I may have the pressure of, say, five or six atmospheres above and a vacuum
below the said piston, so that when the said cam or cams shall leave the lifting
block and release the piston, the latter starts forward with great velocity, and the
drill or perforating implement will strike the bottom of the hole with the full effect
of the power employed to operate the machine
The required turning of the dull or perforating implement upon its axis is effected
by pins, which project from the said cain or cains, and which at the proper times
during the action of the machine come in contact with other pins or studs pro-
jecting from the periphery of the aforesaid lifting block
For effecting the feed or advance of the drill or perforating tool the said block
is fixed on the top of the piston 1od, and the upper portion of it is bored slightly
conical to receive a piece similarly coned or bored to slip over the drill bar This piece,
which may be called the clutch piece, is divided into two or more parts by saw
kerfs, so that it may spring to a very small extent, and it is thus rendered capable
of clutching the drill bar when it strikes into the cone of the lifting block When
the down stroke is nearly terminated a collar on the top of the clutch box comes
in contact with a stop so arranged as to strike it out of gear with the lifting block.
The drill bar is thus set free from the piston rod at the moment of striking the
blow on the rock, and the return stroke is then commenced The revolving cam
first lifts the piston fiom its seat on the cylinder bottom, and immediately after-
wards the lifting block embraces the clutch piece, and carries the dull bar with it,
and the effect of this momentary difference of time between the commencement of
the upward movement of the piston and the clutching of the drill bar is to incioase
'the distance between the point of the dull and the piston, and thus provide the
feed for the following stroke With this construction of the parts, above described,
the feed or advance of the dull will always be greater than the distance which the
'diill penetrates the lock at one blow, but there will be a backward slip of the diill
bar through the piston rod equal to the excess of the feed or advance, so that the
machine is rendered solf-acting, and regulates the distance according to the hardness
of the rock,
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Brown Jordan in the Great Seal Patent Office on the 2nd
August 1877.
THOMAS BROWN JORDAN, of the Firm of Thomas B. Jordan and Son, Engineers
and Contractors, Queen Victoria Street, in the City of London. "AN IMPROVED
MACHINE FOR DRILLING OR BORING ROCKS AND OTHER HARD SUBSTANCES
'
My Invention relates to an improved machine for drilling or boning locks and
. other hard substances.
The principal novel feature of this machine is the employment therein of
pneumatic pressure, as herein-after set forth, and I therefore call the said machine
the pneumatic rock drill.
The said Invention also relates to improvements in the construction and airange- 5
ments of parts of the machine, as herein-after described.
The said Invention comprises the employment of a pneumatic cylinder fitted.
with a piston, which is drawn towards the top of the cylinder by the action of a.

page_text: revolving cam or cams fixed on a shaft, which may be rotated by hand power
applied to a winch, or by gearing with any first mover
The said piston is packed by a cup leather, so that it becomes a perfectly air-
tight partition betweon the portions or volumes of air on each side of it when it is
rising, but permits air to pass by it in its descending stroke to compensate for any
small amount of leakage which may occur The said piston is fitted with a tubulai
rod, which works through a stuffing box or leather collar in the top cover of the
cylinder, or in both covers If in the top cover only I provide holes in the bottom
cover or lower part of the cylinder to allow a free passage for the air to the under
side of the piston, that is to say, I prefer this construction, but I do not confine
myself to the same, as it is obvious that my Invention may be carried into practice
with a vacuum on the under side and a plenum on the upper side of the piston,
or the vacuum only may be used with substantially the same result
When the said piston is drawn up by the action of the revolving cam the whole
of the au above it will be compressed into the space between its top ado and the
under side of the cylinder covei, and as this space may bear any determined pro-
portion to the whole contents of the stroke it is obvious that the machine may be
made to work under any required pressure, so as to utilize to the best advantage
the power at command
The requisite turning of the drill is effected by the action of the said cam on the
under side of a dovico termed the lifting block, or by the engagement of a pro-
jection on the cam with other projections on the edge of the said lifting block.
The forward or feed movement of the drill or tool is obtained by a peculiar
construction of this block, which allows it to move on the drill bar more readily
in one direction than in the other, as herein-after more fully explained; or this
movement may be obtained by a more simple friction clutch In either case the
action is the same The revolving cam strikes the under side of the said lifting
block, and in doing so moves it a short distance up the drill bar (by virtue of its
inertia) before picking it up or griping it, thus increasing the distance between
the point of the tool and the bottom of the piston, and preparing the tool to strike
the rock before the piston comes to the bottom of its descending stroke, the length
of the feed movement is always somewhat in excess of the penetration of the rock,
and the difference between the two distances equals the backward ship of the rod
through the friction clutch, thus the regulation of the feed is rendered automatic in
proportion to the hardness of the rock
In order that the construction and operation of my said Invention may be fully
understood I refer to the accompanying Drawings, in which,
Figure 1 is a side elevation of a machine intended for drilling vertical or slightly
inclined holes
Figure 2 is a fiont elevation with the cylinder, piston, and rod shewn in
section.
The remaining Figures are herein-after described
Similar letters indicate coresponding parts throughout the Drawings.
a is the cylinder, b, the piston, b₁, the tubular rod, e, the drill bar; f, the
lifting block, which is screwed on the top of the tubular piston rod, and is so con-
structed as to hold the drill bar in connection with it by a friction clamp or clutch,
the precise construction of which is more clearly shown in Figures 3 and 4, which
show one form of the said liftang block.
Figure 3 is a side view partly in vertical soction.
Figure 4 is a transverse section on the line x, x, Figure 3.
A friction clutch is inserted into the mortise in the lifting block f, in which it
slides freely when the drill bar is not in place. One end of the slot in the clamping
frame g is filled with a piece of hard wood h, which fits the drill bar, and there is a
similar piece of hard wood h¹ fitting the opposite side of the bar. Both pieces of
wood can be pressed into close and tight contact with the bar e by the screw i, and
the hold in the bar thus obtained is sufficient in drilling locks of average hardness.

page_text: I am, however, aware that the device shewn in Figures 3 and 4, or a substantially
similar device, has been already employed in a rock-drilling machine, and therefore
this device taken separately forms no part of my Invention, but in Figures 5 and 6
I have shewn a novel construction of this device
Figure 5 is a side view partly in vertical section illustrating this novel form of
my lifting block, and other parts of my machine.
Figure 6 is a section on the line y, y, Figure 5. This modification of the lifting
device ensures a more firm and secure hold of the bar e against the force of the
blows of the dull, and is therefore better adapted for very hard rocks than the
device shewn in Figures 3 and 4 The lifting block is mortised, as shewn at 3, to
receive the clamping fiame k, l, l, are two pieces of gun metal, or other suitable
material fitted to the bar e on one side, and made flat on the back or other side;
m, m, are steel plates resting on each other, the back edges of which are on one
side in contact with the end of the said frame, and on the other side with a pressing
piece adjustable by the screw 2
It will be seen that from the inclined position of these plates when the lifting
block is struck upwards by the aforesaid cam there will be a tendency to give them
greater inclination, and to relax then hold on pinch on the bare, but when the
block is released, and the pressure in the cylinder brings down the position to
deliver its blow, the tendency is to decrease the inclination of the plates, and
increase the tenacity of the hold or pinch of the said plates on the bar, hence I
have a clamp which is easily moved upwards on the bar, but can only be moved
downwards with great difficulty, so that I get the whole force of the blow on the
rock without griping the bar so positively or gidly as to prevent the self-adjust-
ment of the feed, according to the hardness of the rock.
To permit this adjustment to be obtained as nearly as possible by hand I provide
the screw i, by which any desired amount of constant friction can be put on
the bai
In Figure 5 m, n, are the aforesaid holes in the lower part of the cylinder a for
permitting the fice access of air to the under side of the piston b
>
In some instances I may form a small hole, or any desired number of such holes,
through the body of the piston, and through the top cover of the cylinder
These holes are fitted with valves acting in such a manner that when the piston is
depressed to the bottom of the said cylinder all the air will pass to the top or
upper portion of the cylinder, which will then by the action of the said valves be
full of au ΟΙ I may accomplish this object in the manner shewn in Figure 2, that
is to say, I form the portion b² of the piston rod tape or conical, and I fit the
piston b with a capability of sliding a short distance, so that in certain positions of
the said piston there will be a space between the same and the 1od on this taper
oi conical portion The said piston is provided with leather, or other suitable
packing material, on its upper side This device forms a valve, and allows the air
to pass from one side of the piston to the other side at the proper times, but I
prefer the construction shewn in Figure 5, wherein the cup leather o scives the
purpose of a valve, and allows the au to pass up through a small space around the
periphery of the piston b during the downward stroke of the latter, as above
specified p is the leather collar in the top cover, q is a cushion of india-rubber,
or other like material, at the bottom of the cylinder
Having thus fully described my said Invention, and the manner of performing
the same, I wish it understood that I claim,-
First In a machine for drilling rocks and other hard substances the employ-
ment or application of an air or pneumatic cylinder and piston, as above
described
Second The lifting device for controlling the feed movement of the drill or tool,
constructed and operating as above set forth.
Thud A machine for drilling rocks and other hard substances, consisting of the
parts shewn in Figures 1 and 2 of the Drawings, including the various modifi-

page_text: cations thereof, herein described, constructed, combined, and operating as above set
forth
In witness whereof, I, the said Thomas Brown Jordan, have hereunto set
my hand and seal, this Second day of August, in the year of our Lord
One thousand eight hundred and seventy-seven.
MTTA
D
TARKK
THO. B. JORDAN. (LS)