IMPROVEMENTS IN STEAM BOILER FURNACES
Year: 1875

page_text: PROVISIONAL SPECIFICATION left by Charles Macc and Thomas
Robinson Carr at the Office of the Commissioners of Patents,
with their Petition, on the 20th July 1875
We, CHARLES MACE, of Sunderland, in the County of Durham, and
THOMAS ROBINSON CARR, of Sunderland, in the County of Durham, do
hereby declare the nature of the said Invention for "IMPROVEMENTS
IN STEAM BOILER FURNACES," to be as follows:-
This Invention has for its object improvements in steam boiler
furnaces, and the improvements relate to the form and construction
of the furnace front.
By means of the improvements increased facility for supplying the
furnaces of steam boilers with fuel is obtained, thereby diminishing the
labor required to charge the furnace; increased facility is also given for
a more perfect distribution of the fuel over the full breadth of fire-
grate at the time of charging the fires, and there is a more perfect com-
bustion of fuel and consumption of smoke.
In one arrangement we effect these objects by placing on the inner
side of the furnace front a hanging flap, by which the aperture in the

page_text: furnace front can be opened or closed at will. The flap is carried by
axes at its upper edge, and to the back of the flap is attached a quadrant
which is led out through an opening in the furnace front above the
firing aperture, and is provided with a handle, by pulling upon which
the hanging flap can be opened inwards to allow of the admission of fuel,
and also of the admission of a current of fresh air directly into the fuel
at the front end of the fire-grate, so as to permeate thoroughly the
whole mass of the fire, and prevent air rising up on to the crown of the
furnace, as is most commonly the case.
The furnace front is also provided with a slab plate sloping downwards
from the ends of the fire-bars to the bottom of the firing aperture at the
front of the furnace, the outer end of the slab plate and bottom of the
firing aperture being brought down to such a lovel-as to-allow of the
admission of the fireman's shovel without the necessity of raising the
shovel to clear the furnace front, as in furnaces hitherto in use. Attached
to the slab plate are two vertical plates, the outer ends of which come
on either side of the firing aperture in the front, and their inner ends
are curved so as to widen out from the aperture to the full width of
furnace, and allow of the full spread of fuel over the fire-bars These
plates also serve as a protection from heat to the furnace front. A
small aperture with doors is also provided in the front for the admission
of fire-irons when needed.
In place of employing a hanging flap on the inner side of the furnace
front supported upon axos as above described, the door may be of a
quadrant shape and be passed at its upper end through a slit in the
furnace front above the firing aperture, so that it may either be drawn
outwardly through this shit as may be required to allow of the admission
of fuel or air through the firing aperture, or may be pushed inwards
until its lower end rests on the slab plate before mentioned and closes
the aperture.
The quadrant shaped door may work upon slides cast upon the vertical
plates before mentioned, and may have attached to it a pair of horns to
allow of cross bars being fitted by which the fireman can regulate the
size of aperture.