IMPROVEMENTS IN DRILLING MACHINES FOR DRILLING BOILER SHELL PLATES AND SIMILAR WORK."
Year: 1875

page_text: LETTERS PATENT to William Allan, of Sunderland, in the County of
Durham, Engineer, for the Invention of "IMPROVEMENTS IN DRILLING
MACHINES FOR DRILLING BOILER SHELL PLATES AND SIMILAR WORK."
PROVISIONAL SPECIFICATION left by the said William Allan at the
Office of the Commissioners of Patents, with his Petition, on the
26th January 1875.
I, WILLIAM ALLAN, of Sunderland, in thc County of Durham,
Engineer, do hereby declare the nature of the said Invention for "IM-
PROVEMENTS IN DRILLING MACHINES FOR DRILLING BOILER SHELL PLATES AND
SIMILAR WORK," to be as follows:-
:-
This Invention has for its object improvements in drilling machines
for drilling boiler shell plates and similar work.
In constructing this boiler or other shell drilling machine I cast in
segments or otherwise a circular bed of a suitable diameter, which bed
is planed or turned with the usual angled edge, and to the side of the

page_text: bed is fitted or cast on a rack. On this bed I fit a table or tables having
in each a pinion gearing with the rack before named, so that this table
or tables can be moved round on the bed in a circular manner. On this
table or tables I fit a base piece, V edged or otherwise, carrying an
upright standard or pillar, this base piece being free to be moved
towards or from the centre of the bed so as to admit of varied diameters
of work being operated upon. To the standard or standards attached to
the base piece or slide I fit a sliding head operated on by a screw for
raising or lowering purposes, and which head also carries a small engine,
which is geared with the drill spindle, also carried by or fitted to the
sliding head. The drill spindle has the usual traversing or feeding
motion.
Round the outside of the bed I fit a steam pipe having cocks or
valves conveniently placed for the drill driving engines, which engines
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Allan in the Great Seal Patent Office on
the 26th July 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ALLAN, of Sunderland, in the County of Durham, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-sixth day of January, in the year
of our Lord One thousand eight hundred and seventy-five, in the 1
thirty-eighth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said William Allan, Her special
license that I, the said William Allan, my executors, administrators,
and assigns, or such others as I, the said William Allan, my executors,
administrators, and assigns, should at any time agree with, and no others, a
from time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN DRILLING
MACHINES FOR DRILLING BOILER SHELL PLATES AND SIMILAR WORK," upon the 3

page_text: condition (amongst others) that I, the said William Allan, my executors
or administrators, by an instrument in writing under my, or their, or
one of their hands and seals, should particularly describe and ascertain
the nature of the said Invention, and in what manner the same was to
be performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that I, the said William Allan, do hereby declaro
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say:-
-
This Invention has for its object improvements in drilling machines
for drilling boiler shell plates and similar work.
In constructing this boiler or other shell drilling machine I cast in
segments or otherwise a circular bed of a suitable diameter, which bed
is planed or turned with the usual angled edge, and to the side of the
bed is fitted or cast on a rack. On this bed I fit a table or tables having
in each a pinion gearing with the rack before named, so that this table
or tables can be moved round on the bed in a circular manner. On this
table or tables I fit a base piece, V edged or otherwise, carrying an
upright standard or pillar, this base piece being free to be moved
towards or from the centre of the bed so as to admit of varied diameters
of work being operated upon. To the standard or standards attached to
the base piece or slide I fit a sliding head operated on by a screw for
raising or lowering purposes, and which head also carries a small engine,
which is geared with the drill spindle, also carried by or fitted to the
sliding head. The drill spindle has the usual traversing or feeding
motion.
'Round the outside of the bed I fit a steam pipe having cocks or

page_text: position, the shells or plates being still placed vertically as in the
arrangement above described.
In the Drawings hereunto annexed Figure 1 shows a front elevation;
Figure 2, a side elevation; and Figure 3, a plan view of a drilling
machine for drilling boiler plates and similar work, in which the work is
fixed vertically and the drill heads are moved around it.
A is the horizontal annular bed with a toothed rack B formed around
it; on this bed are mounted a table or tables C, each carrying a pinion D
to gear with the toothed rack, and on the axis of the pinion is a hand
wheel E, by which the pinion can be turned, and the table C thereby
caused to travel round the bed. F is the base plece mounted on the
table C in such a manner that it can be moved towards or away from
the centre of the bed; G is the upright standard or pillar rising up
from the base piece F; H is the sliding head, which can be raised or
lowered upon the standard; I is the small engine carried by the head
and giving motion to the drill spindle J, as shewn; K is a steam pipe
carried round the bed and having cocks or valves conveniently placed
upon it to allow of the drill driving engines being coupled up with it by
suitable lengths of elastic tubing.
The advantages derived from the above-described construction of
drilling machine are,—
1. The drilling operation is at all times performed in a direct line with
the centre of the object or work.
2. One or more drills can be easily employed, and each can be worked
independently of the others.
3. The boiler or other shell plates can be drilled after being rolled to
their required curve, and whilst they are held in a vertical position.
4. No shifting of the boiler or other plates is required as the drilling
standards are free to revolve round it.
Figure 4 shows a plan view; Figure 5, a vertical section; and
Figure 6, an elevation of parts of the modification of the above arrange-
ment, in which the drill heads remain in a fixed position, whilst the
work is moved round from time to time as required.
A is the bed plate or frame of the machine; B, B, are radial arms
carried by a circular plate turning upon a central axis C; on the under

page_text: side of the arms are rollers F running upon a horizontal annular path-
way E; D are the standards, upon which are carried the sliding heads
which support the drill spindles; the standards D are carried by beds
which can be shifted radially towards or from the centre C; G is the
main driving shaft for transmitting motion to the drills. When more
than one drill is used the shaft gives motion to a central bevil wheel H,
as shown, from which motion is transmitted by the bevil pinions I
gearing therewith, and shafts J to the other drills, or the several drill
heads may be driven by separate engines, as in the former arrangement.
In place of the boiler shell or other plates being carried by the arms B
they might simply be suspended from a crane, and the work whilst thus
suspended may be acted upon by drills working radially around it and
driven in the manner herein-before described.
Having thus described the nature of my Invention and the manner of
performing the same, I would have it understood that I do not confine
myself to the precise details of the construction of the machines abovo
described, but what I claim is,--
First. The employment of direct steam-driven drilling machines free
to be moved round a fixed circular bed, substantially as herein-before
described and illustrated at Figures 1, 2, and 3, for drilling boiler shell
plates or similar work when in a vertical position,
Second. The combined arrangement of machinery, substantially as
herein-before described and illustrated at Figures 4, 5, and 6, for
drilling boiler shell plates or similar work when in a vertical position.
In witness whereof, I, the said William Allan, have hereunto
set my hand and seal, this Twenty-fourth day of July, in the year
of our Lord One thousand eight hundred and seventy-five..