IMPROVEMENTS IN THE FIRE DOORS OF FURNACES
Year: 1877

page_text: ✓ LETTERS PATENT to Charles Mace and Jolin Brewster, both of Sunderland, in
the County of Durham, Engineers, for the Invention of "IMPROVEMENTS IN
THE FIRE DOORS OF FURNACES
"
PROVISIONAL SPECIFICATION left by the said Charles Mace and John
Brewster at the Office of the Commissioners of Patents on the 10th February
1877
CHARLES MACE and JOHN BREWSTER, both of Sunderland, in the County of
Durham, Engineers "IMPROVEMENTS IN TILE FIRE DOORS OF FURNACES"
In constructing a file-door according to this Invention we make it in preference
of a semien cular form, which is balanced by an annular run or pendulum weight
The said dooi, with annulai im or pendulum weight, turns upon an axle, the said
axle being supported by bearings attached to the furnace frame, or the said door
may turn upon a pintle or stud called by the dead plate The fiont of the said
door has a ventilator attached, and the back, or flame plate, is perforated in the
usual manner By applying a lever or handle to the said door, or to the said axle,
and working it, the door may be partly or fully opened, or shut either side of the
furnace, as required by the operator
In case of accident causing the balance of the said door to be destroyed, the
operator can place and maintain it in any required position by the use of a notched
wheel and lever
By another arrangement, our doo is made in halves, on each part is a toothed
wheel (working one into the other), and by operating either handle, the said door can
be turned and secured in the required position by a lover and notched wheel or
otherwise.

page_text: Fig 1 is a vertical section of part of a furnace, showing one arrangement of our
patent door, Fig 2 is a section on line A¹, A¹, Fig 3, Fig 3 is a front view,
shewing the door shut, Fig 4 is a back view, shewing the door open
A is the file-doo1, B is the axle of the same, supported by beaungs C, which
bearings C may be either cast on bolted to the furnace fiame, D is the balance
rim, and by means of the handle or lever E the operator can turn the door to the
equned position, F is the furnace frame, the said frame has a regulator M to
admit au,
which is partly heated by passing round between the fiont of flame and
fire-buck lining next the fiic, which forms the air channel N, before being dis
charged through outlets O to the furnace fire
On the before-mentioned fire-dooi is also a regulator P to admit air, which is
paitly heated before being passed to furnace fine through the perforated back or
Hame plate
In these Figures our patent door, with axle and balance 11m, are cast in one (but
if desired may be made separately), and supported by brackets attached to file-door
frame
Fig 5 is a vertical section showing another arrangement for supporting our
patent door, Fig 6 is a section in line A', A¹, Fig 7, Fig 7 15 a front view,
shewing notched wheel and level
In these Figures, our patent file-door A, caned by the pintle or stud B, is
attached to the dead plate, on the said stud B is fixed a notched wheel H
(Fig 7)
In case of accident causing the balance of the door to be destroyed, the lever I,
which is attached to the said door A, may be placed in the required notch of the
Baid wheel H to maintain the door in its position
Fig. 8 1в a front view shewing another arrangement of our improved fire-door in

page_text: halves Each half door A is carried by studs B attached to either flame F or dead
plate On cach half door A is a toothed wheel L, said wheels working into each
other, and by operating either handle (E) the door can be moved and secured
in the required position by a notched wheel H and lever I, as shewn in Fig 7
Having now particularly described and ascertained the nature and object of the
said Invention, and in what manner the same is to be performed or carried out in
practice, we would have it understood that what we claim is the construction,
application, and use of our improved fire doors, substantially as herein-before
described and illustrated by the accompanying Drawings It being understood that
we do not limit ourselves to the piecise details of construction herein-before
described and shewn by the accompanying Diawings, which we may vary without
departing from the nature and character of the herein described Invention
In witness whereof, we, the said Charles Mace and John Brewster, have
hereunto set our hands and seals, this Eighth day of August, in the year
of our Loid One thousand eight hundred and seventy-seven