CERTAIN IMPROVEMENTS IN FURNACES OR FIRE-PLACES
Year: 1843

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
HOLMES, of Stroudwater, in the County of Gloucester, Engineer, send
greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent, under the Great Seal of Great Britain, bearing date
at Westminster, the Ninth day of November, in the seventh year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said George Holmes, Her especial licence, full power, sole privilege, and
authority, that I, the said George Holmes, my executors, administrators, and
assigns, and such others as I, the said George Holmes, my executors, adminis-
trators, or assigns, should at any time agree with, and no others, from time to
time and at all times during the term of years therein mentioned, should and
lawfully might make, use, exercise, and vend, within England, Wales, and the
Town of Berwick upon Tweed, my Invention of "CERTAIN IMPROVEMENTS IN
FURNACES OR FIRE-PLACES;" in which said Letters Patent is contained a proviso
obliging me, the said George Holmes, by an instrument in writing under my
hand and seal, particularly to describe and ascertain the nature of my said
Invention, and in what manner the same is to be performed, and to cause the
same to be inrolled in Her Majesty's High Court of Chancery within six
calendar months next and immediately after the date of the said in part
recited Letters Patent, as in and by the same, reference being thereunto had,
will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
George Holmes, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, is particularly described and
ascertained in and by the following description thereof, reference being had to
the Drawings hereunto annexed, and to the letters and figures marked
thereon, that is to say:
My Invention of improvements in furnaces or fire-places consists in a novel
or improved mode of admitting air to the flues of furnaces or fire-places, for
the purpose of promoting the combustion of the smoke, and in the means of
regulating the supply of air in proportion to the quantity of smoke that is
evolved from the fuel. The means I employ to effect this object is clearly
shewn in the accompanying Sheet of Drawings, and consist in placing an air
chamber or passage in the ash pit beneath the grate bars, and furnishing it
with doors or valves, which are capable of being opened at pleasure, in any
convenient manner. The mode I prefer is by connecting the valves of the air
passage to the fire door, so that when the latter is opened for the purpose of
charging the fire with fresh fuel, the doors or valves of the air chamber in the ash
pit are also opened, and a large volume of air thereby admitted to the flue of the
furnace, and an apparatus is connected with the doors or valves of the air chamber
for the purpose of preventing them from closing immediately that the fire
door is shut. By means of this apparatus a large quantity of air is admitted
to the flue through or behind the bridge just at the time that the fresh fuel is
thrown on, and a great quantity of smoke is evolved therefrom; but as the
quantity of smoke diminishes the supply of air is diminished by the gradual
closing of the valves or doors, until the said doors are closed entirely. Fig. 1
in the accompanying Sheet of Drawings represents a longitudinal vertical
section of a boiler and furnace with my improvements applied thereto; and
Fig. 2 is a horizontal section of the same, taken in the line 1, 2, of the previous
Figure. a, a, is the furnace, and b, b, b, b, the flue; c, c, is the ash pit, and d, d,
the air chamber, which supplies the flues with air by means of an aperture e
made in the bridge. The air chamber is closed in front by means of doors or
valves f, f, which are hinged to the sides of the chamber, and are opened and
closed by the arms or rods 9, 9, which are jointed to the sliding frame h, h.
This latter carries a long rod or arm i, the outer end of which is jointed to a
double arm or lever j, mounted on the lower end of the vertical shaft k, k.
The opposite end of the double arm or lever j, is jointed to a rod n, the other
end of which bears or acts against a strong helical spring o, placed in a box
which is set in the brickwork. On the upper end of the vertical shaft kan

page_text: arm 1, 1, is mounted, and the outer end thereof is furnished with a segmental
slot, see Fig. 2, in which a pin or stud at the end of the connecting rod m
works, and thereby connects the arm 1, l, to the fire door. When the fire door
is opened it forces back the arm l, and by causing the vertical shaft k to
turn around it draws the long rod i forward, and thereby opens the doors or
valves f, f, of the air chamber, and admits the air into the flue, and when the
fire door is closed again the pin or stud which connects the rod m of the fire
door to the arm or lever 1, 1, slides along the segmental slot formed at the end
of the latter, and by means of an apparatus hereafter described allows these
parts to come back slowly into their original position, and thereby gradually
and slowly close the doors or valves of the air chamber, as has been already
mentioned. The apparatus for gradually closing the doors or valves of the air
chamber after the fire door has been opened and the fuel supplied to the fire is
shown detached, and on an enlarged scale, at Fig 3, 4, and 5. Fig. 3 is a
sectional view of the apparatus; Fig. 4 is a plan view; and Fig. 5 is another
sectional view, but taken in a line at right angles to the line in which Fig. 3 is
taken. The working parts of the apparatus are enclosed in a box p, p, which
is set in the brickwork; k, k, is the vertical shaft before mentioned, which
carries at its lower end the double arm or vibrating lever j,j, one end of which
is connected to the long rod i, Fig. 2, and the other end to the rod n, Fig
2 and 5, which acts against the spring o, as before described. The respective
parts in all the Figures are shown in the position they would occupy when the
fire door is shut and the doors or valves of the air chamber are also closed;
but when the fire door and air chamber valves are open the several parts
would assume the position represented by dots in Fig. 2 and 5. It will be
seen in Fig. 5 that a lever q, q, is connected to the arm n by a joint, and is
made to vibrate backwards and forwards on a moveable pin, stud, or axle 2, at
the outer end of an elbow lever v, as the said arm n is pushed inwards by the
lever j. The lower end of the lever 9 carries a sector rack, which is occa-
sionally put in gear with the small pinion r; on the same shaft as the pinion r
an escapement wheels is mounted, the proper and regular rotation of which
is regulated by the escapement stops t, t, on the vertical shaft t*;, when the
fire door is closed the sector rack at the lower end of the lever q is out of
gear with the pinion, as is clearly seen by the red lines in Fig. 5; but when
the door is opened it forces back the rod or arm n, as has been already stated,
and a stud or stop u on the under side of the arm n is brought into contact
with the upper end of the lever v, which is mounted on a fixed centre at 1, and
carries at its outer end 2 the vibrating lever q before mentioned. By the

page_text: stud or stop u coming into contact with the upper end of the lever v the
lower end 2 is forced down, and the lever 7 which has, by means of the
forward motion of the arm n, been brought into the position shown by dots, is
depressed so as to bring the teeth of the rack into gear with those of the
pinion; then the spring o, which has been collapsed by the advance of the
rod n, will begin to exert its force and drive the said rod back again, and with
it the lever q, and through the intervention of the sector rack will cause the
pinion r and escapement wheels to revolve. The escapement stops t, t, are
mounted on the upper and lower ends of the vertical shaft t*, and immediately
below the lower stop and on the same shaft a horizontal sector rack w is
mounted. This rack gears into a pinion a, on the axle of which is fixed
a small toothed wheel y, which drives a pinion z, which is mounted on the axle
of the fly wheel a. From the foregoing description it will be understood that
the spring o acts upon and drives all this gearing, and that the speed thereof
is regulated by the escapement, which retards its motion and prevents the force
of the spring from expending itself too suddenly, and by this means the valves
or doors of the air chamber are gradually closed, as before mentioned.
Having now described my Invention, and the manner of carrying the same
into effect, I would observe, that many alterations may be made in the arrange-
ment and construction of the various parts of the apparatus without departing
from the principle of my Invention; for instance, instead of the spring o, a
weight may be raised by the action of opening the doors or valves of the air
chamber or passage, and allowed to fall slowly, and thus permit the said doors
or valves to return gradually to their closed position. I claim as the Invention
secured to me under the herein-before in part recited Letters Patent the appli-
cation to furnaces or fire-places of an air chamber or passage provided with
doors or valves, such doors or valves being so arranged as to be capable of
being opened at pleasure either in connection with the fire door or otherwise,
and of returning slowly to their closed position by a retarded action of springs
or weights.
In witness whereof, I, the said George Holmes, have hereunto set my
hand and seal, this Ninth day of May, in the year of our Lord One
thousand eight hundred and forty-four.
GEORGE (L.S.) HOLMES.

page_text: AND BE IT REMEMBERED, that on the same Ninth day of May, in
the year above mentioned, the aforesaid George Holmes came before our Lady
the Queen in Her Chancery, and acknowledged the Specification aforesaid,
and all and everything therein contained, in form above written. And also the
Specification aforesaid was stamped according to the tenor of the Statute in
that case made and provided.
Inrolled the same Ninth day of May, in the year above written.