AN IMPROVED DRILLING MACHINE FOR DRILLING HOLES IN BOILER SHELLS OR OTHER LARGE PIECES OF WORK
Year: 1876

page_text: LETTERS PATENT to William Clark and James Clark, of Low Elswick, in the
Borough and County of Newcastle-upon-Tyne, Marine Engineers and Iron
Founders, for the Invention of "AN IMPROVED DRILLING MACHINE FOR
DRILLING HOLES IN BOILER SHELLS OR OTHER LARGE PIECES OF WORK,"
Sealed the 19th April 1876, and dated the 28th January 1876.
PROVISIONAL SPECIFICATION left by the said William Clark and James
Clark at the Office of the Commissioners of Patents on the 28th January
1876.
WILLIAM CLARK and JAMES CLARK, of Low Elswick, in the Borough and
"AN
County of Newcastle-upon-Tyne, Marine Engineers and Iron Founders.
IMPROVED DRILLING MACHINE FOR DRILLING HOLES IN BOILER SHELLS OR OTHER
LARGE PIECES OF WORK."
Our improvements in drilling machines relate particularly to those cases where
large and heavy bodies, such as boiler shells, cylinders, or any large piece of work,
have to be drilled. It is then desirable that the object to be acted upon should
remain undisturbed as long as possible, every change of position entailing an
expenditure of time and labour.
For this reason we would construct a strong circular table to carry the work, say
a boiler shell, which is made secure thereon. The table is centrally supported
beneath by a vertical shaft or pillar, round which freely revolves a large bevelled
cog wheel communicating motion to a similar but smaller wheel keyed on a long
shaft running the whole length of a radial arm that radiates from and is supported
by the before-mentioned pillar, around which it swings when the horizontal position
of the drill is required to be altered.
The drill is mounted in a box capable of turning the tool at an angle, and of
moving in the ordinary way up and down guides in a vertical standard placed on
the upper face, and on that portion of the said radial arm which extends beyond
the circular table. The position of the standard from the centre of the table, or
from the face of the work thereon, is adjusted by a screwed spindle on the radial
arm working in a box nut fixed to the under side of the said standard. Motion
is given to the spindle by turning a hand wheel at the outer extremity of the
arm.
Rotation is conveyed to the drill by the following means:-The shaft that runs
the whole length of the radial arm, and which derives its motion, as before men-

page_text: tioned, from the large bevelled cog wheel has a keyway from end to end, in which
travels a mitre wheel gearing into a similar wheel keyed to a vertical shaft sup-
ported by and working in the standard, from which power is transmitted through
an ordinary train of wheels to the drill.
Two or more arms may be made to radiate from and to swing round the central
pillar. The large bevelled cog wheel is actuated by the prime mover, and gives the
required power in the manner above described to the same number of drills.
When the machine is to be brought into use the boiler shell is placed on the
circular table, and secured in that position; which offers the greatest facility for
continued employment. An arm is then brought round to where a row of holes is
to be drilled. The drilling box adjusted to the height for. the first hole, and the
tool fitted square to the work, the vertical standard is made to advance to the work
The advance of the
by turning the hand wheel at the outer extremity of the arm.
standard carries with it the mitre wheel keyed in the keyway of the shaft that
runs from end to end of the arm, and to which rotary motion is given by the large
bevel wheel.
Other radial arms are brought into position, and the drills and standards similarly
adjusted, when motion being given to the large bevel wheel the whole system is
set to work.
Ordinary appliances are fitted to the vertical standards to keep the drills up to
their work, and to put them out of or into gear.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by the
said William Clark and James Clark in the Great Seal Patent Office on the
22nd July 1876.
WILLIAM CLARK and JAMES CLARK, of Low Elswick, in the Borough and
"AN
County of Newcastle-upon-Tyne, Marine Engineers and Iron Founders.
IMPROVED DRILLING MACHINE FOR DRILLING HOLES IN BOILER SHELLS OR OTHER
LARGE PIECES OF WORK."
Our improvements in drilling machines relate particularly to those cases where
large and heavy bodies, such as boilers shells, cylinders, or any large, piece of work
have to be drilled. It is then desirable that the object to be worked upon should
remain undisturbed as long as possible, every change of position entailing an
expenditure of time and labour.
To carry out our Invention we construct a strong circular table capable of
carrying the work, say a boiler shell, which is made secure thereon. The table is
centrally supported beneath by a vertical shaft or column, which also gives support
to a large double bevelled cog wheel; this wheel freely revolves round the coluinn,
and communicates motion to a small bevelled wheel keyed on a shaft running the
whole length of and within a radial arm that radiates from the before-mentioned
column, around which it swings when the horizontal position of the drill is required
to be altered.
The drilling tool is mounted in the usual way in a box capable of turning the
tool at an angle, and of moving up and down guides in a vertical standard placed
on, the upper face of that portion of the radial arm which extends beyond the
circular table. The position of the standard from the centre of the table, or from
the face of the work thereon, is adjusted by a screwed spindle in the radial arm
working in a box nut fixed to the under side of the said standard. At the outer
extremity of this spindle is a ratchet lever, which when brought into action causes
the standard to advance to or recede from the work.
To support the weight of the vertical standard, and to give greater stability to
the radial arm, consequently steadiness to the drilling tool, the radial arm is pro-
vided with wheels running on an annular iron track.
Motion is imparted to one

page_text: of these wheels by means of a hand wheel and suitable gearing actuated by the
operator, who can at his pleasure vary the horizontal position of the drilling tool.
Rotation is conveyed to the drill by the following means:-The shaft that runs
the whole length of and within the radial arm, and which derives its power from
the large double bevelled cog wheel, as before mentioned, has a keyway formed
along a portion of its length for a metre wheel to travel therein when the position
of the standard on the radial arm is altered. This mitre wheel works a similar
wheel keyed to the end of a vertical shaft or spindle working in and supported by
the said standard. From this spindle through an ordinary train of wheels rotation
is transmitted to the drill, which is as usual kept up to its work by suitable
means.
Two or more radial arms may radiate from and swing round the central
column and the double bevelled cog wheel, which receives on its under bevel power
from a shaft actuated by the prime mover, transmits that power by means of its
upper bevel to each of the small bevel wheels keyed on the shafts running through
the radial arms, as before mentioned.
This arrangement of the driving gear offers no obstruction to the complete circuit
of the radial arms, and allows each drill to be placed at any desired part of the
circumference of the boiler shell.
Referring to the accompanying Drawing, Figure 1 is an elevation of our improved
drilling machine provided with three radial arms, and Figure 2 a plan of the
same.
In both of these Figures a portion of the structure is removed to shew more
clearly the arrangement of the interior.
Figure 3 is a part section on line 1-2, (Fig. 2) to shew the driving wheel gearing
into the under side of the double bevelled cog wheel.
In all these Figures A is the circular table centrally supported beneath by a shaft
or collumn B, around which freely revolves the double bevelled cog wheel C, which
derives its power and motion from the driving shaft D. The bevel wheel d on
this shaft engages with the under bevel of the wheel C, the upper bevel of the
last-mentioned wheel being employed exclusively in actuating the bevel wheels e, e,
which are keyed on the first-motion shafts E, E, E, from which the necessary power
to drive the drills is derived; F, F, F, are the radial arms or supports for
carrying the standards G, G, G. Each radial arm is provided with wheels f¹, f",
running upon the annular iron track f; they are actuated by the hand wheel H
and suitable gearing, by which means and by aid of the hand wheel H the horizontal
and vertical position of the drilling tool is adjusted by the operator. The drilling
tool g is mounted in a box, and fitted in the usual way with suitable gearing and
guides in the standard G. Power is conveyed from the first-motion shaft E by
means of mitre wheels 1, 7, through the vertical spindle J to the drill. The mitre
wheel is loosely keyed in a keyway on the shaft E to allow it to follow the
standard when the same is adjusted along the top of the radial arm. The base of
the standard is widened out, as shewn on plan, to carry the operator, and is pro-
vided with horizontal guides or ways v, that portion of the radial arm on which
they work being suitably made to receive them. On the under side of the base is
fixed one or more box nuts m, m, made to receive the screwed spindle M, the
turning of which causes the standard to advance to or recede from the face of the
work. This notion is accomplished by pulling over in the desired direction the
ratchet lever n. When the boiler shell S, Figure 1, is secured on the table A each
drill may be brought round to its desired position by turning the hand wheels
H, H, H, which through a proper train of wheels give motion to one of the conical
carriage wheels supporting the outer extremity of the radial arın. The height of
the drilling tool is then regulated by the hand wheel H₁ in the usual way, and the
point of the drill brought within range of the face of the works by means of the
ratchet lever n. During the motion of the standard the mitre wheel is carried
by it along the keyway, keeping the two mitre wheels in gear. The fine adjustment
and feed of the tool is as usual provided for in the hand wheel H".

page_text: All the drills being now in working order, the whole is set in motion by putting
into gear the driving shaft.
The working of each drill is independent of the others, and each can be put into
or out of gear by the operator in the usual way without obstructing the due per-
formance of the rest.
Having now set forth the nature of my Invention of "An Improved Drilling
Machine for Drilling Holes in Boiler Shells or other Large Pieces of Work," and
explained the manner of carrying the same into effect, we wish it to be understood
that under the above in part recited Letters Patent we claim, the employment of a
radial arın travelling upon an annular track to support the drill standard; also, the
double bevelled cog wheel to transmit the power from the prime mover to the first-
motion shaft within the radial arm, in the manner and for the purposes above
described and illustrated on the accompanying Drawings.
In witness whereof, I, the said James Clark, have hereunto set my hand and
seal, this Twenty-first day of July, in the year of our Lord One thousand
eight hundred and seventy-six..