IMPROVE- MENTS IN APPARATUS FOR ADMITTING AND REGULATING THE SUPPLY OF AIR TO
Year: 1867

page_text: LETTERS PATENT to William Begg, of Marsh Lane Foundry, Preston, in
the County of Lancaster, Ironfounder, for the Invention of "IMPROVE-
MENTS IN APPARATUS FOR ADMITTING AND REGULATING THE SUPPLY OF AIR TO
PROVISIONAL SPECIFICATION left by the said William Begg at the
Office of the Commissioners of Patents, with his Petition, on the
18th April 1867.
I, WILLIAM BEGG, of Marsh Lane Foundry, Preston, in the County of
Lancaster, Ironfounder, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN APPARATUS FOR ADMITTING AND REGULATING THE SUPPLY OF
AIR TO FURNACES," to be as follows:-
My Invention relates to mechanical self-acting means for regulating the
supply of air to a furnace through the dead plate so as to accommodate to the
greatest nicety the various stages of combustion of the fuel. I apply a plate
underneath the dead plate working on centres, and at an angle to this movable
plate or door, and attached to it is a box coutaining mercury; this box is
divided into two compartments by a partition which passes in an inclined

page_text: position from the bottom of the box to within a short distance of the top.
Between the movable and dead plates is a stud which is made to slide forwards
and backwards by the opening and closing of the furuace door. When the
furnace door is opened the stud is brought forwards up the incline which lowers
that portion of the movable plate which is in front of its axis and with it the
front compartment of the mercury box, thus the mercury is caused to flow
quickly over the upper edge of the partition into the front part of the box,
causing that end to descend and lowering the front part of the movable plate
and allowing the air to pass freely through the dead plate. When the furnace
door is closed the stud is pushed backwards down the incline, which raises that
portion of the movable plate which is in front of its axis, and with it the front
compartment of the mercury box, causing the mercury to gravitate through au
aperture in the lower part of the partition into the back compartment until it
becomes sufficiently heavy to raise the front of the movable plate, and thereby
prevent the further passage of air through the dead plate. The time required
for this latter may be varied according to the kind and quality of fuel used;
it. would usually occupy about the space of two minutes, but may be
readily made to occupy a shorter or longer time by varying the area of
for the return mercury.
passage
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Begg in the Great Seal Patent Office on the
18th October 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, 1, WILLIAM
BEGG, of Marsh Lane Foundry, Preston, in the County of Lancaster, Iron-
founder, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighteenth day of April, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirtieth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said William Begg, Her special licence that I, the said William Begg, my
executors, 'administrators, and assigns, or such others as I, the said William
Begg, my executors, administrators, and assigns, should at any time agree
with, and no others, 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

page_text: "
APPARATUS FOR ADMITTING AND REGULATING THE SUPPLY OF AIR TO FURNACES,"
upon the condition (amongst others) that I, the said William Begg, 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 Begg, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Sheet of Drawings hereunto annexed,
and to the letters and figures marked thereon (that is to say) :-
is
My Invention relates to mechanical self-acting means for regulating the
supply of air to furnaces through the dead plate so as to accommodate to the
greatest nicety the various stages of combustion of the fuel. For this purpose
I apply a plate underneath the dead plate working on centres and at an angle
to this movable plate or door, and attached to it is a box containing mercury;
this box is divided into two compartments by a partition which passes in au
inclined position from the bottom of the box to within a short distance of the
top. Between the movable and dead plates is a stud which is made to slide
forwards and backwards by the opening and closing of the furnace door.
When the furnace door is opened the stud is brought forwards up the incline,
which lowers that portion of the movable plate which is in front of its axis,
and with it the front compartment of the mercury box. Thus the mercury
caused to flow over the upper edge of the partition into the front part of the
box, that end being lowered together with the front part of the movable plate
and allowing the air to pass freely through the dead plate. When the furnace
door is closed the stud is pushed backwards down the incline, which raises
that portion of the movable plate which is in front of its axis and with it the
front compartment of the mercury box sufficiently to cause the mercury to
gravitate through an aperture in the lower part of the partition into the back
compartment until it becomes sufficiently heavy to still further raise the front
of the movable plate, and thereby prevent the further passage of air through
the dead plate. The time required for this may be varied according to the
kind and quality of fuel used and the power of draft required; it would
usually occupy about the space of two minutes, but may be readily made to
occupy a longer or shorter time by varying the area of passage for the return
mercury.

page_text: Figures 1 and 2 of the Drawing represent longitudinal sections of a Cornish
boiler fitted with apparatus for regulating the supply of air to the furnace.
"
A is the furnace; B, fire-bars; and C, the door arranged as usual; D is the
dead plate with slots or perforations provided, as seen in the plan Figure 3 on
an enlarged scale, for the admission of air to the furnace. The air supply is
regulated by a door or plate E, shown open in Figure 1 and closed in
Figure 2, hung on pivots 1, 1, below the dead plate D, as seen separately in
the cross section, Figure 4, and in front view at Figure 5. The oscillating
motion of this plate E is produced in the first place by the aid of a pin or
stud a sliding to and fro on an inclined surface 6 formed on the top of the
plato E, this pin or stud is connected to the furnace door by a rod or arm c in
such manner that when the door is opened the stud a is brought forwards up
the incline b, the effect of which is to depress the front end of the oscillating
plate E, and open an admission for the air to pass through the dead plate D
into the furnace attached to the under part of the plate E, and at an angle
therewith is a box F containing mercury. This box is separately represented
at Figures 6, 7, and 8, Figure 6 being a plan of the mercury box detached
from the oscillating plate E, Figure 7 a plan of the interior of the box, and
Figure 8 a longitudinal section of the same. The box F is divided into two
compartments d, e, by a transverse inclined partition f extending from the
bottom of the box to within a short distance of the top. This mercury box
being connected with the oscillating plate E participates in its movement, and
on the said plate being tilted as above mentioned by the act of opening the
furnace door the mercury will be caused to flow out of the compartment d
over the inclined partition f into the front compartment e of the box, and so
keep open the plate E for the admission of air through the dead plate D.
The act of closing the furnace door slides the stud a in a backward direction
down the inclined surface b on the plate E, so as to again partially raise the
front of said plate by oscillating it on its axis, and also the mercury box F
attached, the mercury a flowing slowly by gravitation through an aperture g
in the bottom of the partition f back into the compartment d, so as to
gradually raise the plate E until the opening is entirely closed, during which
time (some minutes, more or less,) the air will have free admission through
the dead plate to the furnace, the amount being regulated by varying the
size of the aperture 9 according to the nature of the fuel and the draft
required.
Having described the nature of my Invention, and the manner of performing

page_text: the same, I declare that what I claim as my Invention to be protected by the
berein-before in part recited Letters Patent is, the improvements in apparatus
for admitting and regulating the supply of air to furnaces at the dead plate, as
herein-before described and represented in the Drawings annexed.
In witness whereof, I, the said William Begg, have hereunto set my
hand and seal, this Seventeenth day of October, in the year of our
Lord One thousand eight hundred and sixty-seven.
WILLIAM BEGG. (L.S.)