IMPROVEMENTS IN FURNACES FOR STATIONARY MARINE LOCOMOTIVE AND PORTABLE STEAM-ENGINE BOILERS."
Year: 1882

page_text: 15217
LETTERS PATENT to John William Couchman of No. 7 Stanley Villas Pembury
Road in the Parish of Tottenham in the County of Middlesex Civil Engineer
for an Invention of "IMPROVEMENTS IN FURNACES FOR STATIONARY MARINE
LOCOMOTIVE AND PORTABLE STEAM-ENGINE BOILERS."
PROVISIONAL SPECIFICATION left by the said John William Couchman at
the Office of the Commissioners of Patents on the 29th September 1882.
JOHN WILLIAM COUCHMAN, of No. 7 Stanley Villas, Pembury Road, in the Parish
of Tottenham, in the County of Middlesex, Civil Engineer "IMPROVEMENTS IN
FURNACES FOR STATIONARY, MARINE, LOCOMOTIVE, AND PORTABLE STEAM ENGINE
BOILERS.
'
This invention has for its object improvements in the construction of boiler
furnaces; so as to obtain more perfect results in the combustion of coal, or other
fuel; and the consequent saving in the cost of evaporating a given weight of water.
The main feature of this invention is the application of a distilling chamber or
box; soundly constructed, and formed of cast or wrought iron or steel, fire-clay, or
other suitable material, moulded in one piece, or built up in parts; and of suitable
shape with reference to the particular boiler, but of greater longitudinal than
transverse section in most cases; fully or partially open at one end only, on the
edges of the sides bottom and top; or the sides and top only of which is moulded
or formed a pipe or channel for the conveyance of atmospheric air, having
perforated holes or slots so made as for the most part to direct the outflow of
air across the open end or mouth of the chamber or box and otherwise if
desirable.
For stationary and marine boilers the chamber or box is fixed in the tube or
main passage at the end of the fire bars, with the mouth facing the furnace door;
and the width of the box is so regulated as to leave sufficient space for the passage
of the flames and products of combustion past its sides, and through the tube or
main passage. It is supported at the inner or more remote end on a suitable iron
bearer; and at the front or open end on a hollow cast iron girder with two orifices

page_text: on the upper sides to correspond with the pipe at each side of the chamber
or box; which is conuected by short nozzles and two other orifices on the under
side for connection with tubes running through the ashpit to the front of boiler,
each terminated with a valve of suitable form to regulate the flow of air. An
ordinary ash pit end with door, is fitted under; and the bridge to the furnace is
cast on the girder on each side of the chamber or box seat.
The area of the fire bars of the furnace, as compared with the ordinary dimensions,
is considerably curtailed under this arrangement and the method of working the
furnace is by first lighting the fire on the bars in the ordinary way, and after the
temperature has been raised sufficiently, the chamber, or box is charged with fresh
fuel and so distilled till all or most of the gaseous elements have been evolved;
when the carbonised residuum is drawn on to and spread over the furnace bars,
and the box is again charged, and so on from time to time. All the fresh fuel
being passed into the box and after sufficient distillation removed thence on to
the bars.
The hydro-carbon and other gaseous portions of the fuel are disengaged in the
chamber, or box, as in a gas retort, and mixed in their passage out of the mouth
from the air pipe surrounding it with their due proportion of atmospheric air for
proper combustion, and the carbonised residuum is drawn on to the furnace bars
from time to time and there receives through the ashpit its independent quota of
air to complete its exhaustion, both divisions of the process combining to carry on
the evaporation of the water in the boiler For locomotive and portable boilers
the chamber or box may be fixed immediately under the front of the boiler, and
the air pipes, passed through the sides of the fire box which may be extended in a
slanting direction upwards, and backwards, from the fire bars sufficiently to
embrace the distilling chamber, or box, into which each charge of fresh fuel would
be cast, to disengage the gases; and from which the residuum from time to time
would be drawn into the fire box beneath for exhaustion as in the other cases.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John William Couchman in the Great Seal Patent Office on the
28th March 1883.
JOHN WILLIAM COUCHMAN of N° 7 Stanley Villas Pembury Road in the Parish
of Tottenham in the County of Middlesex Civil Engineer. "IMPROVEMENTS IN
FURNACES FOR STATIONARY, MARINE, LOCOMOTIVE, AND PORTABLE STEAM ENGINE
BOILERS.
This invention has for its object improvements in the construction of Boiler
furnaces, so as to obtain more perfect results in the combustion, of coal or other
fuel; and the consequent saving in the cost of evaporating a given weight of
water.
The main feature of this invention is the application of. a distilling chamber or
box, hereinafter called a Retort, soundly constructed and formed of cast or.
wrought iron, or steel, fireclay, or other suitable material, moulded in one piece,
or built up in parts and of a suitable shape with reference to the particular boiler
and form of fire box or flue, in some cases being of greater longitudinal than
transverse section and in other cases of greater width than length, and fully or
partially open at one end only or if need be closed altogether in some cases by the
action of a door moved by suitable gearing-On the edges of the sides, bottom, and
top; or the sides and top only of which, is moulded or formed a pipe, or channel
for the conveyance of Atmospheric air having perforated holes or slots so made as.
for the most part to direct the outflow of air across the open end, or mouth of the
chamber, or box or otherwise if desirable.
For stationary and marine boilers, the chamber, box, or retort fixed in the
tube or main passage at the end of the fire bars, with the mouth facing the
furnace door; and the width of the retort is so regulated as to leave sufficient.
space for the passage of the flames and products of combustion past its sides, and
through the tube, or main passage, and it is supported at the inner or more remote
end on an iron bearer or bridge of brickwork, iron or other suitable material, and
at the front or open end on a hollow cast iron girder, with two orifices on the
upper side to correspond with the pipe at each side of the chamber, box or retort
which is connected thereto by short nozzles and two other orifices on the face or
under side or other suitable position for connection with certain air tubes running
through the ash pit to the bridge or with slots or holes of any suitable shape and
dimensions each terminated by or fitted with a valve of suitable form to regulate
the flow of air-An ordinary ash-pit with door is fitted under in brick work or
otherwise and such setting in brickwork is employed to concentrate the heat round
the retort as the nature of the boiler suggests and two or more retorts may be
employed in the same furnace by enlarging the furnace part of the tube to admit
of the additional number
The area of the firebars of the furnace as compared with those of ordinary
dimensions, curtailed under this arrangement, and the method of working the
furnace, is by first lighting the fire on the bars in the ordinary way, and after the
temperature has been raised sufficiently, the chamber or box or retort is charged
with fresh fuel which thereby is distilled until all or most of the gaseous elements
have been evolved when the carbonized residuum is drawn on to and spread over
the furnace bars, and the box is again charged; and so on from time to time all, or
a large proportion of the fresh fuel being passed first, into the box and after
sufficient distillation removed thence on to the bars and from time to time fresh
coals or fuel may be thrown on to the bars directly to promote the action of the
retort and maintain the required temperature.
The hydrocarbon, and other gaseous portions of the fuel are disengaged in the
chamber or box or Retort as in a gas retort and mixed in their passage out of
the mouth from the air pipe or ring surrounding it with their due proportion of

page_text: atmospheric air regulated by the valves on the inlet pipes or on the air girder for
proper combustion;-the carbonised residuum is drawn on to the furnace bars from
time to time and there receive with such fresh coals as may be thrown on the
bars direct, through the ashpit their independent quota of air to complete the
combustion both divisions of the process combining to carry on the evaporation of
the water in the boiler.
For Locomotive and portable boilers, the chamber, or box or retort may be fixed
immediately under the front of the boiler or in any other suitable position in the
firebox or furnace and the air pipes passed through the sides or any suitable part
or parts of the firebox or furnace which may be enlarged if necessary sufficiently
to embrace the distilling chamber or box or retort into which each charge or the
whole or greater proportion of fresh fuel would be cast to disengage the gases;
and from which the residuum from time to time would be drawn into the fire box
beneath or around for exhaustion as in the other cases.
This retort principle of furnace also embraces and includes the prevention of
smoke.
And in order that my said invention may be more clearly understood, reference
is hereby made to the accompanying drawings in which similar letters of reference
indicate corresponding parts in the several figures.
Fig. 1 is a horizontal section of a Cornish steam boiler-Fig: 2 is a vertical
section of the retort formed in one with the air chamber b. b.-Fig: 3 is a front
view of the retort-Fig: 4 is a plan or horizontal section of the retort-Fig: 5 is a
front view and Fig: 6 a horizontal view of one of the air tubes c. c. Fig: 7 is
a front view of the lower air chamber e. Fig: 8 is a top view and Fig: 9 à section
of the same Fig: 10 is a longitudinal section of the boiler and Fig 11 a cross
section of the same through the fire bars.
a is the retort into which fresh coals are thrown-b is the semicircular air
chamber which is supplied with air in regulated quantities by means of the air
tubes c. c which have doors at f, for that purpose. The air which enters the
tubes c. c becomes heated in its passage through c to the chamber e The air then
passes by the passages g g to the chamber b--This latter chamber b has openings
or perforations in its inner periphery, whereby the air is enabled to mix with the.
gas which emanates from fuel in the retort a and the incandescent fuel on the bars
supplies the necessary heat for effecting the combustion of the gases which then
flow outside the retort to and past the bridge d to the flue.
Having thus particularly described and ascertained the nature of my said
invention and the manner in which the same is to be performed and carried into
effect, I claim :-
1. The use and manufacture, in connection with steam boiler furnaces, of the
retorts, air chambers, passages and regulators for the purposes substantially as
herein before described and shewn on the drawings, or any mere modification
thereof.
2. The general arrangement and construction of parts of steam boiler furnaces
together forming my improvements in furnaces for stationary marine, locomotive
and portable steam engine boilers, severally herein before described and shewn on
the drawings, or any mere modification thereof.
In witness whereof I the said John William Couchman have hereunto set my
band and seal this twenty eighth day of March in the year of our Lord.
One thousand eight hundred and eighty three.