IMPROVEMENTS IN OR CONNECTED WITH BOILER AND OTHER FURNACES
Year: 1882

page_text: LETTERS PATENT to John Henry Johnson of 47 Lincoln's Inn Fields in the
County of Middlesex Gentleman for an invention of "IMPROVEMENTS IN
OR CONNECTED WITH BOILER AND OTHER FURNACES" A communication
from abroad by by Edward J. Mallett, Junior of the City County and State
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at the
Office of the Commissioners of Patents on the 11th May 1882.
JOHN HENRY JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman. "IMPROVEMENTS IN OR CONNECTED WITH BOILER AND OTHER
FURNACES A communication from abroad by Edward J. Mallett Junior of the
City County and State of New York United States of America.
"
These improvements are the development or outgrowth of the system of
promoting the combustion of fuel in boiler and other furnaces as described in the
Specification to Letters Patent granted to my foreign correspondent on the 15th
February 1882 No. 737 the same being mainly characterized by the employment of
distinct and separate inlets which admit each in adjustable quantity the one, air to
the fire through the ash pit the other heated air into the furnace at a point where
it will meet the fuel gases in conjunction with a suction fan for inducing draft and
a condenser which acts to cool the heated air or gas from the furnace at the time
or before it is drawn into the fan.
The improvements consist Firstly In the employment of a damper or system of
dampers by which the draft during the time that the furnace door or doors are
opened may be diverted from the usual flame passage over the bridge wall or
through the septum wall, and caused to follow a path which is down through the
grate and mass of superincumbent fuel and thence out from the rear part of the
ash pit into the combustion chamber beyond the fire box, the fuel gases which
follow this path meeting as before the heated air which issues from the rear ends
of the tubular grate bars. The object of this damper arrangement is to prevent
the formation of smoke at the time the furnace door or doors are opened as they
must be from time to time in order to keep the furnace chirgel.

page_text: A sliding register or gate is provided for regulating the admission of air to the
interior of the grate bars; a like register is applied to the air inlet openings at the
front of the ash pit the two registers being usually connected to a lever handle by
means of which both are simultaneously moved in opposite directions so that in
proportion as the one is closed the other is opened.
The second part of this Invention consists in the employment in conjunction
with the suction fan or air exhauster of certain forms of condensers. One of these
condensers can be used with good effect when it is desired to utilize the heat of
the furnace gases for heating water as for instance the boiler feed water; the other
is designed particularly for use with locomotives or in other connections where
economy of space is of much consideration although it may be applied generally to
furnaces worked under my system.
The condenser may consist of a drum or casing filled to the desired extent with
horizontal superposed coils of tubing forming a continuous pipe or coil through
which water is caused by suitable instrumentalities to circulate entering the coil
at the lower point and leaving it at the upper point.
The suction fan is connected to the condenser and the flue is similarly connected
thereto within the casing at the top is a water supply pipe and rose the spray
from which mingles with the heated gases passing into the condenser and saturates
them with vapor.
The hot air or gas loses heat by vaporizing the water, and is also put in a
condition to readily impart heat to the coil conducting and also radiating heat
much more readily than if it were dry.
The third part of this invention relates to the application and use substantially
as hereinafter described of exhaust steam for heating and ventilating purposes.
Under my system of promoting the combustion of fuel in boiler purposes the
exhaust steam which usually employed in locomotive and other engines to create
and maintain the requisite draft in the furnace is no longer needed for that purpose;
and I utilize said exhaust steam in beating both the water which is fed to the
boiler and also air. The exhaust steam is acted on by a combined pneumatic and
water condensing apparatus it parts with its heat to both the water and the air;
when condensed it forms part of the heated feed water; and the heated air from
the condenser can by suitable appliances be distributed throughout the various
railway carriages composing the train or the various parts of a steam ship or other
structure with which the apparatus may be connected.
The exhaust steam from the engine cylinders may pass through a pipe to the
feed water tank. The pipe discharges into a chamber in which a number of tubes
are provided open at each end. The rear ends of the tubes are covered by a
hood communicating with a suction fan on the rear of the tender driven by a
small engine or by any other suitable means and acting to draw air through the
tubes. The exhaust steam heats these tubes to a temperature corresponding to
the pressure of the steam and the rush of air through the tubes condenses in part
the steam. The air is of course heated usually to a high degree and may if desired
be conducted to the several railway carriages composing the train through a pipe
leading from the fan along beneath the floors of the carriages the pipe sections
and
having flexible couplings at the points when the carriages join one another;
said pipe discharges the air into the carriages through registers in the floor of the
same. This system is also available in steam ships where the exhaust steam of the
engine is usually condensed by a salt water condenser. The condensing chamber
is intermediately situated between two water compartments. The upper one
contains cold water; the lower one contains water which has been heated by the
exhaust steam together with the off condensation.
It may be here remarked that the suction fan is a convenient means for creating
the draft but other known forms of air exhausting appliances may be employed as
for instance the steam jet arrangement which is employed in locomotives. When
the furnace is in operation the suction fan (driven by any suitable instrumentality)
creates a draft through the furnace-the air entering through the registers in

page_text: regulated quantities-The fuel gases as they pass out through the openings in the
septum meet and mingle with the heated air issuing from the rear ends of the
hollow grate bars; and the hot air before it reaches the fan is cooled by the action
of the condenser through which it passes.
When the fire door is opened the damper is swung from this position to one
in which it closes the openings in the septum wall and uncovers the opening in the
rear wall of the ash pit. Inasmuch as in practice the register of the ash pit is
closed when firing it follows that at this time all air that gains access to the
furnace excepting that which passes through the grate bars (whose register is open
at this time) enters through the fire door or doors and is thence drawn downwardly
through the grate into the ash pit and out from the same into the combustion
chamber or due beneath the boiler meeting on its way the heated air issuing from
the rear ends of the hollow grate bars. The result is that the gases from the fresh
fuel with which the furnace is being charged are drawn down through the
incandescent mass of fuel below and I in this way obtain smokeless flame. When
the fire door is closed the damper is returned to its former position.
In some cases if desired the damper can be maintained permanently in its raised
position in which case the register openings in the front of the ash pit would be
dispensed with and in lieu thereof requisite openings in the fire door or furnace
front arranged to admit air above the fire would be employed. The course of this
air would be down through the fuel into the ash pit and thence out through the
rear opening to meet the heated air issuing from the rear ends of the grate bars.
It is desirable in some cases to make the damper automatic in its action. One
convenient arrangement for this purpose is to connect one end of the shaft on
which the damper is mounted with the fire door by a cord or chain which extends
therefrom over suitable guide pulleys or rollers to the front of the fire door to
which it is fastened. Upon the end is also fixed a sector to the periphery of which
is attached a chain or cord from which a weight is suspended. When the door
is opened the cord is slackened and the weight causes the damper shaft to partially
rotate in a direction to swing the damper up far enough to cover the openings in
the septum. When the door is again closed the cord will be pulled and caused to
unwind and in so doing will cause the damper to swing down to its original
position against the resistance offered by the weight. The parts can be arranged
so that they will be very nearly counterpoised and thus may be operated without
exertion.
The external surface of the coil can be washed and kept clean by a water
jet or distributor from which water can be showered down upon the coil.
In applying the condenser for promoting the combustion in the boiler furnace
of locomotives some slight modifications are necessary and which consist chiefly in
the arrangement of the fan which is attached or applied directly to the front end
of the boiler or of the smoke box the fan casing being virtually a prolongation or
an extension of the casing of the boiler. The fan thus draws air directly through
and from the boiler flues takes up but little room and does not detract from the
symmetry of the locomotive.
By this mechanical draft arrangement I am enabled to dispense entirely with
the use of exhaust steam for creating draft in locomotives whereby important
results are obtained.
At the rear of the chamber is a box the sides of which are perforated for
entrance of the exhaust steam. In the floor of chamber are openings placed so as
to open into both the box and the chamber and leading into the chamber below.
From the upper chamber leads a pipe terminating in a rose from which water is
sprayed or showered in determined quantity into the box; the pipe can have a
valve or cock for controlling the water flow.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Henry Johnson in the Great Seal Patent Office on the
13th September 1882.
JOHN HENRY JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman "IMPROVEMENTS IN OR CONNECTED WITH BOLLER AND OTHER
FURNACES a communication from abroad by Edward J. Mallett Junior of the
City County and State of New York United States of America.
"
This Invention relates to improvements being the developement or outgrowth of
the system of promoting the combustion of fuel in boiler and other furnaces for
which I obtained Letters Patent dated 15th February 1882 No. 737 the same being
characterized mainly by the employment of distinct and separate inlets which
admit each in adjustable quantity the one inlet admitting air to the fire through
the ash pit and the other inlet admitting heated air into the furnace at a point
where it will meet the fuel gases in conjunction with a suction fan for inducing
draught and a condenser which acts to cool the heated air or gas from the furnace
at the time or before it is drawn into the fan.
The improvements consist Firstly In the employment of a damper or system of
dampers by which the draft during the time that the furnace door or doors are
opened may be diverted from the usual flame passage over the bridge wall or
through the septum wall and caused to follow a path which is down through the
grate and mass of superincumbent fuel and thence out from the rear part of the
ash pit into the combustion chamber beyond the fire box the fuel gases which
follow this path meeting as before the heated air which issues from the rear ends
of the tubular grate bars. The object of this damper arrangement is to prevent
the formation of smoke at the time the furnace door or doors is or are opened
as they must be from time to time in order to keep the furnace charged.
The Invention further consists in the employment in conjunction with the
suction fan or air exhauster of certain forms of condensers. One of these con-
densers can be used with good effect when it is desired to utilize the heat of the
furnace gases for heating water as for instance the boiler feed water; the other is
designed particularly for use with locomotives or in other connections where
economy of space is of much consideration although it may be applied generally to
furnaces worked under the system under consideration.
The Invention further relates to the application and use substantially as herein-
after described of exhaust steam for heating and ventilating purposes. Under the
afore said system of promoting the combustion of fuel in boiler furnaces the
exhaust steam which usually is employed in locomotive and other engines to create
and maintain the requisite draught in the furnace is no longer needed for that
purpose and said exhaust steam is utilized in heating both the water which is fed
to the boiler and also air. The exhaust steam is acted on by a combined pneumatic
and water condensing apparatus it parts with its heat to both the water and the
air; when condensed it forms part of the heated feed water and the heated air
from the condenser can by suitable appliances be distributed throughout the various
railway carriages composing the train or the various parts of a steam ship or other
structure with which the apparatus may be connected.
The first portion of the present improvements is illustrated in Figures 1 2,
and 3 of the accompanying drawings.
Figure 1 is a longitudinal vertical section of the furnace.
Figure 2 is a horizontal section of the same.
Figure 3 is a perspective view of part of the furnace.

page_text: A is the body of the furnace B the boiler, C the ash pit D the fire box; E the
hollow grate bars open from end to end-their rear ends extending through to the
rear of the septum or division wall F and being supported in boxes therein; his
the sliding register or gate for regulating the admission of air to the interior of
the grate bars, i is the like register applied to the air inlet openings g at the front
of the ash pit the two registers hi being usually connected to a lever handle by
means of which both are simultaneously moved in opposite directions so that in
proportion as the one is closed the other is opened. f are the openings in the
septum or division wall F through which the fuel gases pass into the flue beyond;
G is the conductor or draft flue; J is the condenser and H is the suction fan or air
exhauster. It may here be remarked that the suction fan is a convenient means
for creating the draught but other forms of air exhausting appliances may be
employed as for instance the steam jet arrangement which is employed in
locomotives-When the furnace is in operation the suction fan (driven by any
suitable means) creates a draught through the furnace-the air entering through
the registers hi in regulated quantities-The fuel gases as they pass out through
the openings meet and mingle with the heated air issuing from the rear ends of
the hollow grate bars and the hot air before it reaches the fan is cooled by the
action of the condenser through which it passes. K is a damper hinged to the
rear face of the box a. It is represented in Figures 1 and 3, in the position it
occupies when the fire door is closed and in this position it covers and closes an
opening or openings r in the rear wall of the ash pit which opening or openings
communicate with the combustion flue or chamber beyond. When the fire door
is opened the damper is swung from this position to one in which it closes the
openings in the septum wall F and uncovers the opening r. Inasmuch as in
practice the register i of the ash-pit is closed when firing it follows that at this
time all air that gains access to the furnace (excepting that which passes through
the grate bars whose register h is open at this time) enters through the fire door or
doors and is thence drawn downwardly through the grate into the ash pit and out
from the opening r into the combustion chamber or flue beneath the boiler meeting
on its way the heated air issuing from the rear ends of the hollow grate bars-
The result is that the gases from the fresh fuel with which the furnace is being
charged are drawn down through the incandescent mass of fuel below and in this
way smokeless flame is obtained. When the fire door is closed the damper K is
returned to its former position.-In some cases if desired the damper K can be
maintained permanently in its raised position or in other words the openings fin
the wall F may be permanently closed; in which case the register openings in the
front of the ash pit would be dispensed with, and in lieu thereof requisite openings
in the fire door or furnace front arranged to admit air above the fire would be
employed. The course of this air would be down through the fuel into the ash pit
and thence out through the rear opening r to meet the heated air issuing from the
rear ends of the grate bars.
It is desirable in some cases to make the damper automatic in its action-One
convenient arrangement for this purpose is to connect one ends of the shaft on
which the damper is mounted with the fire door by a cord or chain t which as
indicated in Figure 2 extends therefrom over suitable guide pulley or pulleys or
rollers to the front of the fire door D¹ to which it is fastened-Upon the end s is
also fixed a sector 8 to the periphery of which is attached a chain or cord v from
which a weight wis suspended. When the door D' is opened (as indicated by
dotted lines Figure 2) the cord t is slackened and the weight w causes the damper
shaft to partially rotate in a direction to swing the damper K up far enough to
cover the openings f by which action the cord t is wound upon the end 8. When
the door is again closed the cord t will be pulled and caused to unwind from the
end 8 and in so doing will cause the damper to swing down to its original position
against the resistance offered by the weight w. The parts can be arranged so
that they will be very nearly counterpoised and thus may be operated without
exertion.

page_text: Another part of the improvements is illustrated in Figures 1, 4 and 5.
Figure 4 is a horizontal section of the condenser shown in vertical section in
Figure 1.
In the condenser J represented in the said Figures 1 and 4 the drum or casing
is filled to the desired extent with horizontal superposed coils of tubing forming a
continuous pipe or coil z, through which water is caused by any suitable means to
circulate entering the coil at the lower part x and leaving it at the upper part y.
The suction fan H is connected to the condenser at H and the draught or discharge
flue G is connected thereto at G¹ or vice versa. Within the casing at the top is a
water supply pipe and rose of the spray from which mingles with the heated gases
passing into the condenser and saturates them with vaporized water. The hot air
or gas loses heat by vaporizing the water and is also put in a condition to readily
impart heat to the coil z conducting and also radiating heat much more readily
than if it were dry air. The coil z may be connected with the boiler so as to
supply thereto heated feed water. The amount of water sprayed into the
condenser should be just sufficient to saturate the heated gases with moisture and
should not be admitted in so great quantity as to recondense and collect within
the case of the condenser. The external surface of the coil can be washed and
kept clean from any soot that may collect by a water jet or distributor o from
which water can be showered down upon the coil.
This device is used only when it becomes desirable to wash the coil the water
thus used for scrubbing purposes will gather at the bottom of the casing whence it
may be drawn off by suitable means. The pump or engine which causes
water to pass through the coil z should be placed on the inlet side x and not
between the outlet y and the boiler.
Another form of condenser is shown in Figure 5 which represents one practical
way of applying this improved system of promoting combustion to the boiler
furnace of a locomotive. In this arrangement the condenser consists simply of an
annular water jet or perforated pipe o supplied with water from a suitable source
as for instance from the locomotive tender or boiler and placed at or in the inlet
opening of the fan case through which the highly heated gaseous products of com-
bustion are drawn into the fan. The spray from this pipe becomes at once vaporized
by contact with the fuel gases and serves to cool down the latter. The quantity
of water entering the fan from the pipe is so regulated that it shall by its
vaporization be just sufficient to cool the air within the fan without any water
accumulating within the fan.
Parts marked with like letters in Figures 1 and 5 represent corresponding parts.
The damper arrangement herein before described is not represented in Figure 5 but
it can if desired be applied to the boiler furnace of the locomotive there shown.
The improvement illustrated in Figure 5 besides the condenser already referred
to consists mainly in the arrangement of the fan H which is attached or applied
directly to the front end of the boiler or of the smoke box-the fan casing being
virtually a prolongation or an extension of the casing of the boiler. The fan thus
draws air directly through and from the boiler without an intervening flue takes
up but little room and does not detract from the symmetry of the locomotive.
The fan casing can if desired form the front head of the boiler casing or smoke box
and can be binged or otherwise made movable so that it may be swung to one
side in order to expose the boiler tubes or it may rest on the pilot of the engine.
The gases drawn in by the fan are cooled by the condenser 03 and are discharged
through suitable outlets in the periphery of the casing. The fan driving engine I
can be conveniently arranged in front of the fan. A side elevation of a locomotive
provided with the draught arrangement is shown in Figure 10. By this mechanical
draught arrangement the use of exhaust steam for creating draught in locomotive
and other boiler furnaces in which steam may be used to heat and maintain the
draught can be entirely dispensed with whereby important results are obtained for
not only does the use of exhaust steam for this purpose result in back pressure in
the steam cylinders but the heat contained in the exhaust steam thus voided into

page_text: the smoke funnel is lost. By the present improvement the loss of engine energy
due to back pressure is prevented and the exhaust steam can be utilized for heating
purposes and may be recondensed and returned to the boiler.
An arrangement for thus utilizing the exhaust steam constituting the third
portion of these improvements is represented in Figures 6 to 10 inclusive.
Figure 6 is a sectional plan of the locomotive tender or the line 2, 2, Figure 7.
Figure 7 is a section on the line 3-3 Figure 6. Figure 8 is a section on the
line 4-4. Figure 6. Figure 9 is a section on the line 5-5 Figure 6 and Figure 10
is a side elevation of the locomotive its tender and part of a railway carriage
coupled to the latter.
The exhaust steam from the Engine cylinders is conveyed through a pipe a² to
the feed water tank which in this instance is in the tender. The pipe a² discharges
into a chamber 62 in which are a number of tubes c² extending from front to rear
of the tender and open at each end. The rear ends of the tubes are covered by a
hood d² communicating with a suction fan H' on the rear of the tender driven
by a small engine L₁ or by any other suitable means, and acting to draw air
through the tubes. The exhaust steam entering the condensing compartment b³
heats the tubes c² to a temperature corresponding to the pressure of the steam and
the rush of air through the tubes in part condenses the steam surrounding the
tubes. The air passing through the tubes is of course heated usually to a high
degree and may if desired be conducted to the several railway carriages composing
the train through a duct or pipe e² leading from the fan along beneath the floors of
the carriages, the duct or pipe sections having flexible couplings at the points
where the carriages join one another and said duct or pipe e discharges the air
into the carriages through register controlled openings in the floor of the said
carriages. I am thus enabled to utilize the heat of the exhaust steam for the
purpose of heating and ventilating railway carriages. This system is also available
in steam ships where the exhaust steam of the engine is usually condensed by a
salt water condenser. In such cases I substitute in part for the latter condenser a
pneumatic condenser similar in principle to the one hereinbefore described.
Fresh air can thus be distributed by pipes and registers to all parts of a ship.
The condensing chamber b which the exhaust steam enters is situated between
a water compartment f2 above and a water compartment g² below.
The upper
one contains cold water; the lower one g³ contains water which has been heated
by the exhaust steam together with the water resulting from condensation of the
exhaust steam. A convenient arrangement for bringing the exhaust steam into
contact with the feed water is represented in Figures 6, 8, and 9.
At the rear of the condensing chamber 62 is a box h² whose walls extend between
from the top to the bottom of the chamber, the sides of this box are perforated
at for entrance of the exhaust steam. In the floor of chamber 62 are openings
placed so as to open into both the box h² and the chamber 62 outside and leading
into the chamber g2 below. From the upper chamber f' leads a pipe terminating
in a rose ² from which water is sprayed or showered in the requisite quantity into
the said box h² the pipe can have a valve or cock for controlling the water flow.
The operation is as follows: The uncondensed portion of the exhaust steam enters
the box h² through the apertures i² and is condensed by coming into contact with
the water spray and imparts heat to the water. This heated water and the water
of the Steam, condensed in the chamber be outside the box ² pass down through j³
into the chamber g and the water is thence pumped back to the locomotive boiler
in the usual way. I thus utilize the exhaust steain for the purpose of heating both
the feed water and air. I recondense it and return it to the boiler as part of the
feed water and I obtain a supply of pure heated air which is available for heating
and ventilating purposes.
Having now described and particularly ascertained the nature of the said
Invention and the manner, in which the same is or may be used or carried into
effect, I would observe in conclusion that what I consider to be novel and original

page_text: and therefore claim as the Invention secured to me by the hereinbefore in part
recited Letters Patent is :-
First: The damper or its equivalent for closing alternately the opening in
the septum wall and the opening in the ash pit substantially as shewn and
described.
Second-The combination with the septum wall and the ash pit of the damper
the fire door and means substantially as described whereby the damper is auto-
matically operated to close either the opening in the septum wall or the opening in
the ash pit wall according as the door is open or shut substantially as described.
Third The combination of tubular grate bars or other inlets for conducting
air to a point where it will meet and mingle with the fuel gases an air admitting
inlet above the grate an escape opening in the ash pit whence the air drawn
from the inlets above down through the grate passes to the flue beyond and the
auction fan or other air exhauster with or without the condenser substantially as
described.
Fourth-The condenser consisting of the combination of an outer drum or case,
pipes through which water is caused to circulate and around which heated gases
pass and a water jet or spray for moistening the gases substantially as described
and represented in Figure 1 of the accompanying Drawings.
Fifth-In the herein before described system of promoting combustion the suction
fan adapted to locomotive or other boilers in such manner as to constitute the head
of the boiler casing.
Sixth-The combination with the locomotive boiler and fire box provided with
separate and distinct sets of valve or register controlled air inlets as described of
the suction fan or air exhauster placed in advance of the boiler and in communi-
cation with the boiler flues substantially as described.
Seventh: The combination of the suction fan and a water sprayer delivering
water into the fan substantially as shewn and described.
Eighth Apparatus for condensing exhaust steam and heating both air and
feed water substantially as described and illustrated in Figures 6 to 10 both
inclusive of the accompanying Drawings.
In witness whereof I the said John Henry Johnson have to this my
Specification set my hand and seal this twenty eighth day of August
One thousand eight hundred and eighty two.
יד
זר גרודד
TAINCON
לדברודז
JOHNSON. (L.S.)