Improvements in Furnace Firebridges.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in Furnace Firebridges.
I, HENRY BRANSOM, of Leighton Buzzard, Bedfordshire, Miller, do hereby
declare the nature of this invention to be as follows:-
This invention relates to an improved construction of furnace bridge to admit air
to the flue behind the fire to enable the smoke to be consumed.
According to this invention I construct the bridge as a box through which
air passes and enters the flue at the back of the fire, within the box are a number of
baffle plates to check the passage of the air for the purpose of retaining the same
to enable it to become heated before passing in to the flue. The front of the
bridge is provided with a rest for the one end of the bars to bear upon. In the lower
part of the front of the bridge is a damper arrangement to enable the quantity of
air to be admitted, to be controlled.
.. 10
1007
FREDERIC PRINCE,
Agent for Applicant.
I, HENRY BRANSOM, of Leighton Buzzard, Bedfordshire, Miller, do hereby
declare the nature of this invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained, in and by the following
statement:
-
This invention relates to an improved construction of furnace fire bridge,
adapted to admit a properly controlled supply of heated air into the passage,
heating chamber or flue behind the fire and thereby cause the smoke to be
consumed.
I will describe my invention with reference to the accompanying drawings
whereon is shown an example of construction oy which the application of the
invention can be readily understood. Fig. 1 is a longitudinal vertical section
showing a portion of the furnace tube of a boiler with my improved furnace bridge
in position therein. Fig. 2 is a front sectional elevation of same. Fig. 3 is a
front view of the apparatus with the front cover removed and Fig. 4 is a rear
elevation of the fire bridge.
According to my invention I construct the bridge in box form composed, for
example of a main rear part A, having forward sides or edges A¹, (Figs. 1 and 3)
and a front plate B, which may be secured against the said edges A¹ and held
thereto by bolts C, C¹. When the fire box is circular the box like fire bridge
077

page_text: is made to conform thereto but obviously it should be adapted in form to the
configuration of the fire box: at the upper part the casing A, B, is open and
is fitted with a hood D, the exit aperture of which faces in the direction of the
fire draught as shewn at Fig. 4. The front plate B is provided with a rest E,
for the fire bars F, and is formed with an aperture B₁ at the lower part of the
bridge and the aperture is fitted with a damper G, Divotted at G, G¹, to brackets
on the front plates B. Within the box like fire bridge I provide a number of
baffle plates H, (Fig. 3) to deflect or check the passage of the air for the purpose
of retarding same so that it may become heated before passing into the flue.
It will now be understood that upon the damper G, being opened which may
be effected in any convenient manner, for example by levers or connecting rods
from the fire door not shown in the drawings thus air passes into the heated interior
of the casing, becomes heated therein and passes out in the heated state by the
hood opening and has a regenerative effect upon the products of combustion and
smoke is thereby consumed and economy of working effected.
Having now particularly described and ascertained the nature of this invention,
and in what manner the same is to be performed, I declare that what I claim is:-
1. In furnace fire bridges the combustion of a hollow box like casing, a front
air entrance aperture beneath the fire bars, a damper to control such aperture,
means for operating the damper from the exterior of the furnace, baffle plates
within the casing, and a directing hood by which the air leaves the casing in a
heated state and is diverted into the direction of the fire draught substantially as
and for the purposes described.
2. The arrangement and combination of parts composing my improved furnace
fire bridge all constructed and acting substantially as shewn and described with
reference to the accompanying drawings..
FREDERIC PRINCE,
37, Cursitor Street, Chancery Lane, London,
Agent for Applicant.