IMPROVEMENTS IN MACHINES FOR DRILLING OR PERFORATING ROCKS OR OTHER HARD SUBSTANCES
Year: 1883

page_text: LETTERS PATENT to Alfred Shedlock, of the City and State of New York,
United States of America, Mechanical Engineer for an Invention of
"IMPROVEMENTS IN MACHINES FOR DRILLING OR PERFORATING ROCKS OR
OTHER HARD SUBSTANCES
"
PROVISIONAL SPECIFICATION left by the said Alfred Shedlock at the
Office of the Commissioners of Patents on the 31st July 1883.
ALFRED SHEDLOCK, of the City and State of New York, United States of
America Mechanical Engineer, "IMPROVEMENTS IN MACHINES FOR DRILLING OR
PERFORATING ROCKS OR OTHER HARD SUBSTANCES "J
This invention relates to machines for drilling holes in rocks and the like and is
adapted to be operated by one man, it being provided with a scat upon which the
operator rests
"
The frame-work is so constructed as to enable the machine to be worked on
uneven surfaces, and is also arranged to be folded up along the body of the machine
to facilitate the transportation of the same The power is applied to two crank
handles on a shaft which is fitted in fixed bearings in the upper part of the frame
and actuates, by means of bevel wheels, a vertical shaft in the centre of the frame
This vertical shaft is square or provided with a feather or spline so as to rotate a
cam fitted in a bearing in the upper end of the body, on whatever part of said shaft
the cam may be.
The body which is cylindrical is free to slide on the guide bars of the frame and
the cam having peripheral enlargements is adapted to raise a tool holder by means
of rollers on its upper end. The lower end of the tool-holder projects through the
bottom of the body and is provided with a chuck to receive. the drilling tool. A
spring is located between the bottom of the cam and the tool-holder to force the
drilling tool against the rock when the holder is released from the cam.
The friction of the vertical shaft in the hole in the cam, through which it passes
is sufficient to hold up the body and working parts when the cam is raising the
tool-holder and drilling tool against the resilience of the spring. The weight of

page_text: the body is such as to counteract the rebound of the spring when the drill strikes
the rock and also to slightly compress the spring when the cam is free on
the vertical shaft and the drill resting on the rock, so that the body with the
working parts fall down the guide bars of the frame only so fast as the drilling
tool perforates the rock
To cause the drilling tool partly to rotate after each stroke projections aro
formed on the outside of the drill holder and arranged to bear against longitudinal
ribs on the inside of the cylindrical body, and pass over the tops of the said ribs,
and against another set of ribs just before the cam raises the tool holder to its full
height, and when the full height of the tool holder is attained and it is released
from the cam the projections thereon pass down the succeeding spaces between the
longitudinal ribs in the body. By means of this invention all the essential
functions necessary to the proper working of an automatically acting rock drilling
machine, that is to say, raising the drilling tool away from the rock, partly rotating
it when so raised, forcing the drilling tool violently against the rock, and feeding
the body and working parts forward only so fast as the drilling tool perforates
the rock, are performed by simple mechanical devices operated and governed by
means of one cam.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
tho said Alfred Shedlock in the Patent Office on the 29th January 1884.
ALFRED SHEDLOCK, of the City and State of New York, United States of
America, Mechanical Engineer "IMPROVEMENTS IN MACHINES FOR DRILLING OR
PERFORATING ROCKS OR OTHER NARD SUBSTANCE3
"
This invention relates to machines for drilling or perforating rocks or other hard
substances, and comprises the novel construction and arrangement of parts as
hereinafter described.
The rock drilling machine constructed according to this invention is designed for
drilling holes in a downward direction.
In tho accompanying drawing:
Figure 1 is a side elevation of the improved machine.
Figure 2 is a plan view of the same.
Figure 3. is a side elevation partly in section, drawn to an enlarged scale, of the
body and other parts.
Figure 4 is a vortical section on tho line x, x, Figure 3.
Figure 5 is a transverse section on the line y, y; Figures 3 and 4.
Figure 6. is a transverse section on the lines, ;
Figure 7 is a view of the drill chuck detached and
Figures 8, 9, 10, and 11 are diagrams showing the development of the actuating
cam and device for causing the rotation of the drill.
The frame of the machine consists of two vertical guide bars a and a', fitted at
their upper ends to the head piece u and at their lower ends to the foot picces a³
to which is connected, by means of the bolt at, the double-pointed support a
adapted to rock on the bolt to permit the guide-bars a and a¹ to be set vertically
on uneven ground. To the head piece a² are secured, by means of bolts and nuts
ba, b, the bracing bars b. and b', connected together by the cross-brace b³, and to
the foot piece a³, are secured, by means of bolts and nuts c, c, the two curved
bars c and c', which are pointed and curved outwardly at their ends as shown at
Figure 2., so as to provide a broad base for the machine. The bracing bars b, and b¹
and the curved bars c and c¹ on each side of the machine are claimpel together by
the double yokee c³, c', adapted to allow the bars to bo moved in relation to ono
another so that the pointed ends of the curved bars c, and c¹ may be adjusted to
meet uneven parts of the rock, as shown at Figure 1, and be held firmly, when
adjusto, by means of the set-screws which pass through the sides of the double
yokes c³, c
The nuts of the bolts b³ and c³, c² are also tightened when the frame is adjusted
in the desired position.
It will be observed that the guide bars a and a¹ may be set vertically or at a fow
degrees from the vertical, thus providing means for drilling holes at different
angles to the horizontal. On the cross-brace 3, is attached the seat d by means of
the hooks d, so that it is readily removed to allow the machine to Lo fixed to
cccupy enall space for transportation and other purposes, the bracing bars b and b',
and curved bars cand c¹ being then folded alongside tho guide bars a and a', by
eliding the bars b, and b' out of the double yokes c³, c*,
All the principal operating parts of the machine are located in the cylindrical
body e, and all the movements necessary for the proper working of the drill are
accomplished by means of one cam.
The body e is provided with four lugs e, c', through which the guide bara a.
and a pass, and it has a cap e screwed into its upper end. In the centre of this.

page_text: cap e² works the bush bearing f, having a square hole formed through it and a
screw-thread on its lower end by which it is secured to the double peripheral
cam g, which, when rotated, acts against the two rollers h, h on studs secured to
the inside of the upper end of the drill-holder i. This drill-holder is shown as
being cylindrical in form and having a neck i¹ at its lower end to rotate and slide
longitudinally in a hole in the bottom of the body e;
In the extreme end of this neck i¹, is formed a hole in which the shank of the
drill ; is fitted, the said drill being securely held therein by means of the yoke-
clutch k formed, as shown at Figure 7, with two inclined sides, one of which fits into
a groove cut through the side of the neck into the hole in which the shank of the
drill j is placed so as to press against the shank; the other one bears against the back
of the neck i¹, when the set-screw k¹ is forced against the neck, so that a wedging
action is thereby employed to hold the drill firmly in the neck it, and as there are
three points of contact the liability of the drill becoming loose is reduced to a minimum.
To cause the drill to be partly rotated after each stroke,. two series of ribs
and m are formed on the inside of the body e, the number of ribs in each series
being equal to the number of strokes the drill is designed to make during one
revolution, which in the present case is eleven: and on the outside of the drill-
holder i are formed ribs or projections n, so located as to bear against the ribs Ɩ,
or m. There may be as many of these projections n, as there are ribs in each
series, but four only are shown as affording sufficient wearing surface. The upper
series of ribs m are placed opposite the spaces between the lower series of ribs 4,
and the action of the projections n; thereon, when the cam g is rotated, will be
hereafter explained.
The cam g is rotated by means of the square shaft o, secured to the bevel wheel p
fitted to rotate in the centro of the head piece a of the frame, and with this
wheel p engages the bevel wheel q secured to the horizontal shaft q' also having
its bearings in the head piece a², and to the ends of which are secured the crank
handles r. The wheel bears such rolation, as to size, to the wheel p. that one
full revolution of the handles produces two strokes of the drill as will be hereinafter
explained.
9
Inside the drill-holder i, between its lower end and the washer a¹, bearing
against the bottom of the cam g is placed the spiral spring 8.
"
It will be observed that by arranging the working parts on a common axis, all
pressure due to the compression of the spring a when the cam g is rotated, is
resisted by the metal of the cam between its underside and the faces of its rises,
thereby leaving the cam g free to rotate against the cape without undue friction.
The hook t is for the purpose of holding up the body e when the drill is not in
u, indicates a water can for supplying water to the point of the drill, the
quantity so supplied being regulated by the cock u².
use.
The operation of the improved drill is as follows; the body is allowed to slide
down the guide bars a and a¹ until the end of the drill rests on the surface to bo
drilled the body then being supported by the spring 8, which is slightly compressed
thereby, so that the bottom of the drill-holder i is away from the bottom of the
body. Upon turning the crank handles r, the cam g is rotated, which, acting
against the rollers h, h, raises the drill and bolder i, and compresses the spring 8,
which causes a torsional strain on the square shaft o, as well as tends to turn the
body e; thus producing sufficient friction between the square shaft o and cam-
bearing f, and between the guide bars a and a¹ and the holes through which they
pass in the body e, to prevent the body and other parts from falling
In the diagram, Figures 8, 9. and 10, the dotted triangles represent the formation
of one side of the cam g, and the dotted circle one of the rollers h. The projec-
tions n at the commencement of rotation of the cam bear against the side of the
ribs Z, see Figure 8, and slide up these ribs, as the drill-holder is raised, until their
lower ends clear the tops of the ribs; this occurs just before the rollers h reach the
summit of the cams, the cams then forcing the projections n over the tops of the
ribs l, see Figure 9, until they come in contact with the ribs m; the drill-holder

page_text: and drill have now made one eleventh of a revolution; the cams, in' clearing
themselves of the rollers h, h, raise the projections n a short distance up the side
of the ribs m, see Figure 10. Figure 3 also shows the position of these parts
of the machine at this time. As soon as the cams leave the rollers, the projections n
fall down into the next spaces between the ribs as the drill is forcibly driven
against the rock by the spring a; the speed of the drill is such that it reaches the
rock before the body (which is now released by the torsional strain being removed
from the square shaft O.) has had time to fall to interfere with the propor action
of the spring 8.
The weight of the body is such as to counteract the rebound of
the spring so that the full force of the energy expended in turning the crank
handles is utilized in effective work, the body and cam falling together as fast as
the drill cuts so as to maintain their relative working positions with the drill-
holder.
Instead of making the body heavy enough to produce the effect described,
stirrups may be attached thereto in which the operator can place his feet to offer
the desired resistance to the rebound by foot-pressure.
The double cam g, in making one revolution, would raise the drill-holder twice,
provided the drill-holder fell down with tho projections n in the same spaces in
which they are raised, but as the cam has to carry the holder-partly around equal
to the spacing of the ribs b, which, in this case, is the one-eleventh of a revolution,
it is necessary that the teeth in the wheel g bear the proportion to those in the
wheel pas thirteen (13) is to eloven (11), when it is desired to produce two strokes
of the drill for cach full revolution of the crank-handles. The number of teeth of
the wheel 9 and p, may bear any relation to one another desired without interfering
with the principles of operation of the machine.
In Figure 11 the ribs 7 and m aro shown as having parallel sides, but I prefer to
make one side of them inclined as shown in the other views, as the projections n,
slide more freely up the inclined sides and greater strength is given to the ribs
The shaft o, instead of being square may be round with a flat side or keyway
to work against a key fixed in the bush-bearing f.
Having thus fully described my said invention and the manner of performing
the same I wish it understood that I claim in a machine for drilling or perforating
rocks or other hard substances
First. A cylindrical sliding body, having an enclosing cap, and provided with
internal ribs, a drill-holder extending through the bottom of the body and provided
with ribs arranged to work against and be guided by the ribs in the body, and a
cam located in the upper end of the body and adapted to raise the drill-holder, all
the said parts being arranged on a common axis, substantially as, and for the
purpose, set forth.
Second. The combination of a sliding body a drill-holder, arranged within and
extended through the bottom of the body, a cam fitted to rotato in the upper part
of the body, a spring located between the drill-holder and the cam, and a fixed
rotating shaft adapted to actuate the cam in all positions occupied by it and the
body and to hold the body stationary by friction due to the resistance offered by
the cam when the drill-holder is being raised thereby, all arranged on a cominon
axis, substantially as set forth
Third. In combination, the bevel wheels g and p secured respectively to the
shaft g and to the shaft o, the cam g, the drill-holder i provided with pro-
jections n, and the body e provided with the ribs and m, substantially as set
forth.
Fourth. The combination of the drill-holder i, with the projections n, the spring 8
placed between the cam g and the drill-holder i, the cam g, the body e, and the
ribs and m, substantially as set forth.
Fifth. A frame composed of the rods a, a, the foot piece a³ and the head piece a³,
tho actuating mechanism carried by the body e adapted to freely slide on the
rods a, a', the shaft q' with the bevel wheel q, and the bevel wheel p connected to

page_text: the shaft o adapted to actuate the mechanism carried by the body in all positions
of the same on the rods a a¹, substantially as, and for the purpose, set forth.
Sixth. The combination of the guide bars a, a', the head and foot pieces a³ and
a³, the bracing bars b and 6, the curved pointed bars o and c¹ forming the rear
supporting legs of the machine, the clamping yokes c³, c, and the cross brace b³ and
seat & attached to the cross braco, substantially as set forth.
Seventh The drill-holder provided with projections, in combination with a cam;
a spring located between the drill-holder, and the cam, and a sliding body provided
with ribs, all the said parts being arranged on a common axis, whereby the drill
holder is raised to within a short distance of its throw, then partly rotated, then
completely raised, and then freed from the cam and forced back by the spring,
substantially as, and for the purposo, set forth.
In witness whereof I the said Alfred Shedlock, have hereunto set my hand and
-seal this Thirty-first day of December in the year of Our Lord One thousand eight
hundred and eighty three.