for Effecting Combustion of Fuel with Air Under Pressure.
Year: 1886

page_text: Date of Application, 2nd Sept., 1886.
Complete Left, 27th May, 1887.
Complete Accepted, 28th June, 1887.
for Effecting Combustion of Fuel with Air Under Pressure.
I, JOHN REED FOTHERGILL, of No. 1 Bathgate Terrace, West Hartlepool, in the
County of Durham, Superintending Marine Engineer, do hereby declare the nature
of this invention to be as follows :-
In the specification of an application for Letters Patent made by me on the 4th day
of May 1886 No. 6051 is described an invention having reference to furnaces or
apparatus such as those of marine steam boilers in which combustion of fuel is effected
with air supplied to the furnace under pressure, the said invention relating to the
supply and admission of air to the fuel in the furnace proper as also to the gases
evolved from the said fuel in such a manner as to ensure their more complete
combustion; and my present invention has reference to the use in combination with
furnaces or apparatus constructed in accordance with the invention described in my
said former specification of certain additional features or arrangements the nature of
which will be hereinafter described, and which have for object to divert the gases from
the fuel in such manner that more intimate union or mixture of such gases with the
air supplied for supporting combustion may be effected, and also to obviate loss of
heat arising from the passage of cold air through the boiler whilst cleaning fires and
so forth. My invention may be applied in connection with boilers of various
constructions whether single or double ended, when constructed according to my said
former specification, the air for supporting combustion being supplied under pressure
by any
suitable means such as by forcing it in by a fan inducing a current by means
of a jet or jets of steam or by both these means. For the purpose of diverting the
gases in such a furnace, I provide at a suitable distance behind the bridge (or behind
each bridge where there are several) a partial division or deflector constructed of any
suitable refractory material such as fire brick, the arrangement being such that when
the air is supplied through the pipe or pipes, perforated chamber or chambers
arranged in the back or sides of the boiler as mentioned in my said former
specification it will meet and unite with the gases evolved from the fuel, thereby

page_text: effecting more perfect combustion. The partial divisions or deflectors may be of any
suitable form, it being understood that the shape and position will depend to some
extent upon circumstances. In the case of a double ended boiler in which air cannot
conveniently be admitted into the combustion chamber as in the case of a single ended
boiler such as just referred to, the air supply may be admitted under the bridge and
partial division or deflector, the diversion of the gases in such a case being effected
much lower than is the case when the air is admitted at the back of the boiler as
described. This arrangement is applicable also to a single ended boiler or may be
used in conjunction with the admission of air at the back and sides as before
described.
For the purpose of obviating loss of heat arising from the passage of cold air
through the boiler whilst cleaning fires etc., each nest or box of tubes is partitioned
off in the uptake or smoke box into a separate compartment having a distinct and
independent damper in such a manner that when such damper is closed the ordinary
rush of cold air through the nest or box of tubes is prevented.
. 1
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C.,
Agent for the Applicant.

page_text: for Effecting Combustion of Fuel with Air under Pressure.
I, JOHN REED FOTHERGILL, of No. 1, Bathgate Terrace, West Hartlepool, in the
County of Durham, Superintending Marine Engineer, do hereby declare the nature of
this invention, and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :-
In the specification of an application for Letters Patent made by me on the 4th day
of May 1886 No. 6051 is described an invention having reference to furnaces or
apparatus such as those of marine steam boilers in which combustion of fuel is effected
with air supplied to the furnace under pressure, the said invention relating to the
supply and admission of air to the fuel in the furnace proper as also to the gases
evolved from the said fuel in such a manner as to ensure their more complete
combustion and my present invention has reference to the use in combination with
furnaces or apparatus constructed in accordance with the invention described in my
said former specification of certain additional features or arrangements the nature of
which will be hereinafter described and which have for object to divert the gases
from the fuel in such manner that more intimate union or mixture of such gases with
the air supplied for supporting combustion may be effected, and also to obviate loss
of heat arising from the passage of cold air through the boiler whilst cleaning fires,
and so forth. My invention may be applied in connection with boilers of various
constructions whether single or double ended, when constructed according to my said
former specification; the air for supporting combustion being supplied under pressure
by any suitable means, such as by forcing it in by a fan, inducing a current by means
of a jet or jets of steam, or by both these means.
Referring to the accompanying two sheets of illustrative drawings
Fig. 1 shows in longitudinal vertical section a marine boiler embodying my present
invention.
Fig. 2 is a vertical section in line X X of Fig. 1.
Fig. 3 shows in longitudinal vertical section a double ended marine boiler
embodying my invention.
Fig. 4 is a cross section on line Z, Z, of Fig. 3.
Fig. 5 is a detail view.
The same numerals are used to denote the same or like parts wherever they occur
in the different views; also parts hereinafter specifically mentioned, and which are
the same as shown in the drawings annexed to my said former specification are
marked with the same reference numbers in my present drawings as in the former
drawings.
The general arrangements of furnaces, means for admission of air, and fire-grates,
illustrated respectively by Figs. 1 and 3, resemble those described in my said former
specification, but for the purpose of diverting the gases from the furnace 5, I provide

page_text: at a suitable distance behind the bridge 37 (Fig. 1) or, where there are more than
one, then behind each bridge (see Fig. 3) a partial division or deflector 38,
constructed of any suitable refractory material, such as fire-brick, the arrangement
being such that when the air is supplied through the pipe or pipes 20, and perforated
chamber or chambers 21 arranged in the back or sides of the boiler, as mentioned in
my said former specification, it will meet and unite with the gases evolved from the
fuel, thereby effecting more perfect combustion. The partial divisions or deflectors
may be of any suitable form, for instance as shown clearly in Figs. 2 and 4. These
figures illustrate two forms in which such divisions or deflectors may be constructed.
Fig. 2 shows an arrangement that takes the form of a fire-brick ring constructed or
built up of segmental pieces. Fig. 4 shows an arrangement in which the segmental
pieces are supported upon angle irons 39 fastened to the furnace side. It is, however,
to be understood that the shape and position of such divisions or deflectors will
depend to some extent upon circumstances. In the case of a double-ended boiler in
which (owing to any cause, such for example as want of room, or complication of
arrangement) air cannot conveniently be admitted into the combustion chamber in
the manner in which it is admitted in the arrangement of single ended boiler
illustrated by Fig. 1; the air supply may be admitted as I will now explain by
reference to Fig. 3 (that is to say) through the perforated apparatus 27 (like that
described in my former specification) provided at the ends of the ash-pits 7, and under
the bridges 37 and partial divisions or deflectors 38, the diversion of the gases in
such a case being (as will be seen) effected much lower than is the case when the air
is admitted at the back of the boiler as previously described.
The arrangement of partial division or deflector shown in Fig. 3 with air supply
admitted under the bridge 37 is also applicable to a single ended boiler, or may be
used in conjunction with the admission of air at the back by the pipes 20 and
perforated chambers 21 (see Fig. 1) in the case of a single ended boiler, and in the
case of a double ended boiler in conjunction with the admission of air by the side or
bottom pipes 20 and perforated chambers 21 (see Fig. 3) as fully set forth in my said
former specification.
It is to be noted that I do not lay any broad general claim to the use in a furnace of
a partial division or deflector located behind an ordinary bridge; but by the
application of the partial divisions or deflectors behind the bridges in conjunction with
the means referred to for admitting air in such a manner that, entering through
the perforated chamber or chambers, it will meet and unite with the gases evolved
from the fuel, I am enabled to ensure more perfect combustion of fuel than heretofore
has been usual.
For the purpose of obviating loss of heat arising from the passage of cold air through
the boiler whilst cleaning fires, etc., each nest or box of tubes is partitioned off in the
uptake or smoke-box into a separate compartment (to which separately no claim is
made) and I provide, attached to each smoke-box door, a distinct and independent
damper so arranged that whilst cleaning a fire the nest or box of tubes in connection
with the fire is during such operation and whilst the damper is closed partitioned or
shut off in the uptake or smoke-box in such a manner as will prevent the ordinary
rush of cold air through the nest or box of tubes.
48
Referring to Figs. 1 and 5-10 is the damper attached by the hinge 42 to the
smoke-box door 41 which door is of the ordinary type suspended to the uptake by the
hinges 43 and fastened at the bottom by the latch or fastener 44. Across the inner
side of the smoke-box door a bar 45 is rivetted so that the damper when open rests
against it as shown in Fig. 1. 46 is a notched bar or rod connected to the double eye
which is rivetted to the damper. This bar or rod is for closing and opening the
damper or it may be held in any intermediate position by the steel plate 47, rivetted
to the smoke-box door, engaging in the notches of the bar or rod 46. Instead of such
a bar or rod, a handle can be attached at the bottom of the damper. The damper
sides are flanged so that when it is closed (see Fig. 5) the nest or box of tubes is for
the time being practically partitioned or shut off. The bar or rod 46 when the

page_text: damper is open (see Fig. 1) is held fastened by a hook or button close against the door
so that when the door is opened the damper cannot fall down.
Although I have illustrated my invention as applied to marine boilers, it will be
evident it may be adapted to boilers of other types, and that the details of construction
may be modified to meet the requirements of particular applications.
Having now particularly described and ascertained the nature of the said invention,
and in what manner it is to be performed, I declare that what I claim is
1. In a marine boiler or other furnace for combustion of fuel with air under
pressure, the use in conjunction with the ordinary bridge or bridges and with a
perforated chamber or chambers located behind the said bridge or bridges of a partial
division or deflector or partial divisions or deflectors between the bridge or bridges and
the perforated air chamber or chambers, the arrangement and operation being substan-
tially such as hereinabove described with reference to and illustrated by Figs. 1 and 2,
or Figs. 3 and 4 of the drawings annexed.
2. The application in each compartment of a divided smoke-box of the improved
form of damper herein described and shown, the arrangement being such that by the
closing of the proper damper (i..e, that arranged in connection with the particular
nest or box of tubes to be shut off) the nest or box of tubes in connection with a fire
being cleaned or otherwise operated upon will be for the time being partitioned or shut
off in such a manner as to prevent the passage of cold air through the tubes as above
set forth.
3. The combination and arrangement of apparatus shown in and described with
reference to Figs. 1, 2, and 5 of the drawings annexed.
4. The combination and arrangement of apparatus shown in and described with
reference to Figs. 3 and 4 of the drawings annexed.
1
Al 1
1007
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C.,
Agent for the Applicant.
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C.,
Agent for the Applicant.