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

page_text: Filed 23rd April 1883.
65
TO ALL TO WHOM THESE PRESENTS SHALL COME I JOHN HENRY
JOHNSON of 47 Lincolns Inn Fields in the County of Middlesex Gentleman Send
Greeting WHEREAS Her Most Excellent Majesty Queen Victoria by Her
Letters Patent under the Great Seal of Great Britain and Ireland bearing date
at Westminster the fifteenth day of February in the year of our Lord One
thousand eight hundred and eighty two in the Forty fifth year of Her Reign
did for herself her heirs and successors give and grant unto me the said John
Henry Johnson any executors administrators and assigns Her special License full
power sole privilege and authority that I the said John Henry Johnson my
executors administrators and assigns or such others as I the said John Henry
Johnson my executors administrators or assigns should at any time agree with
and no others from time to time and at all times thereafter during the term
therein expressed should and lawfully might make use exercise and vend within
the United Kingdom of Great Britain and Ireland the Channel Islands and the
Isle of Man an Invention for IMPROVEMENTS IN AND CONNECTED WITH BOILER
AND OTHER FURNACES a communication to me from abroad by Edward J. Mallett
Junior of the City County and State of New York in the United States of
America for the term of fourteen years thence next ensuing And whereas in
pursuanco and performance of a proviso in the said Letters Patent contained I
the said John Henry Johnson did within six Calendar months next after the
date of the said Letters Patent namely on the fifteenth day of August in the
year of our Lord One thousand eight hundred and eighty two cause a Specification
in writing under my hand and seal purporting to particularly describe the nature
of the said Invention and in what inanner the saine was to be performed to be.
duly filed in the Great Seal Patent Office And whereas since the filing of the
said Specification I the said John Henry Johnson have ascertained that the first
and sixth claiming clauses in the said Specification contained might be held to be
too broad as covering matter which was not in itself new at the date of the said
Letters Patent and I am therefore desirous of amending the said Specification as
hereinafter more fully appearing NOW KNOW YE that I the said John Henry
Johnson by and with the leave of Her Majesty's Attorney General and for the
reason aforesaid do amend the said Specification in manner following that is to
•
and daring
+

page_text: st
which is contained in
"
say I strike out the first claiming clause lines 31, 32, 33, 34 and 35 of
page 5 of the Queens Printers Copy of the said Specification published at the
Commissioners of Patents Sale Department in One thousand eight hundred and
eighty two I also strike cut the word "Second' which occurs at line 36 of the
said page 5 and substitute therefor the word "First "-I also strike out the word
Third" which occurs at line 40 of the said page 5 and substitute therefor the
word "Second " I also strike out the word "Fourth" which occurs at line 44 of the
said page 5 and substitute therefor the word "Third "-I also strike out the word
"Fifth which occurs at line 49 of the said page and substitute therefor the
word "Fourth" I also strike out the sixth claiming clause which is contained in
lines 52, 53, 54, 55 and 56 of the said page 5. I also strike out the word "Seventh
which occurs at line 57 of the said page 5 and substitute therefor the word "Fifth "
I also strike out the word "Eighth" which occurs at line 3 of page 6 of the
said Queens Printers Copy of the said Specification and substitute therefor the
word "Sixth" I also strike out the word " Ninth" which occurs at line 9 of the
said page 6 and substitute therefor the word "Seventh." And in order that the
effect of the said Disclaimer may be clearly understood I annex hereto a copy of
the said Specification as it will appear when so amended the preamble and testing
clause being omitted.
"
The Improvements constituting this Invention have reference to promoting the
combustion of fuel in boiler and other furnaces the object being to effect as far as
possible complete combustion of all the fuel gaseous as well as solid so as to
utilize the same in the production of heat
To attain this result according to this Invention a draught is created and main-
tained by an active mechanical appliance such as a fan or air Exhauster instead of
by a chimney smoke stack or the like. This appliance acts to draw or suck the
air through tho furnace in contradistinction to impelling or forcing it into the
furnace The fan or air Exhauster in thus acting necessarily will take heated (and
consequently expanded) air unless some means be provided by which the air can be
reduced in temperature before it reaches the fan. The objection to taking highly
heated and consequently expanded air into the fan aside from the fact that the
heat necessarily injures and toon destroys the fan is that the latter must necessarily
be of very much larger size and will require more power to drive it than otherwise
would be the case. For this reason there is interposed between the furnace and
the fan an air cooling and condensing appliance which may be termed a water-
contact condenser through which all the air drawn through and from the furnace
passes and by which it is cooled before reaching the fan a draught flue being
provided as a communication between the furnace and the Condenser. The Con-
denser may be made in various ways but it is preferred to use for the purpose a
vessel containing screens of coke or other suitable material upon which water in
comparatively small quantity is constantly discharged. The heated air passing up
through the bed of Coke is brought into direct contact with the water trickling or
filtering down through the same and by this direct contact is cooled to the requisite
extent It is also desirable in connection with the suction draft to provide separato
ducts or air inlets the one admitting air beneath the grate bars in the usual way
and the other admitting heated air at a point where it will meet and mingle with
the fuel gases and to provide in connection with these separate inlets registers or
means by which the proportionate volumes of air admitted at these points may be
regulated and varied at pleasure. It is preferred to use for this purpose tubular
grate bars open at each end-Their outer ends as well as the air inlet openings in
the ash pit are provided with registers or gates by means of which the volumes
of air admitted at each of these points can be regulated with nicety The two
sets of registers or gates for convenience sake and to insure their simultaneous
adjustment are connected to be operated by a single lever or handle whose
movement causes the closing of one set of Registers proportionately to the
opening of the other set-In lieu of the ordinary bridge wall a septum or division
wall is used provided with one or more openings through which the products of

page_text: combustion pass from the fire box to the discharge flue; and the inlets or ducts
which supply the air needed to effect the combustion of the fuel gases are so placed
that the air will meet and mingle with the fuel gases at the point where they pass
through or issue from the openings in the Division wall the object being to compel
a complete and intimate commingling of the fuel gases with heated air whereby the
combustion of those gases is effected.
The accompanying drawing represents a boiler furnace embodying my improve-
ments in their preferred form.
Figure 1 is a front sectional elevation of a boiler furnace embodying the
improvements.
Figure 2 is a longitudinal vertical section of the same.
Figure 3 is a vertical central section of the Condenser together with the fan and
its driving Engine mounted thereon.
Figure 4 is a perspective view enlarged of the front end of one of the tubular
grate bars.
Figure 5 represents the key by which each bar may be both rotated and moved
lengthwise backwards and forwards.
A is the body of the furnace and B is the boiler. These parts may be of any
approved construction C is the Ash pit and D is the fire box. The grate bars E
are metal tubes open from end to end-Their front ends are supported in and oper
through the front wall of the furnace-Their rear ends extend through to the rea
of the septum or division wall F and are supported in boxes a therein The grate
bars (with a view to keeping them clean and also to keeping the fire clear) are so
arranged as to be capable of being both rotated on their axes and of being moved
backwards and forwards in the direction of their length-In order to thus actuate
them, use is made of a key G Figure 5 having an end b of a size to fit into the
grate bar provided with laterally projecting lugs or pins c adapted to enter and
engage with bayonet slots d which are formed in the front end of the grate bar as
shewn in figure 4. The stain or handle of the key G is jointed at e so that the
outer portion of the handle may be turned to an angle with the other part to obtain
the leverage required in order to rotate the grate bar
Air is admitted to the furnace at two points namely through the hollow grate
bars whence it is discharged in highly heated condition at a point beyond the
wall F so as to meet and mingle with the gaseous products of combustion passing
through the openings f in that wall as indicated in figure 2 and through the
openings g in the ash pit whence it passes up between the grate bars to the fire in
the usual way.
It is essential in order to secure perfect combustion to regulate the proportionate
volumes of air admitted at these two points and to this end the inlet ends of the
grate bars are provided with a sliding register hand the inlet openings g with a
like register i It is preferred to connect the two registers h and i by means of
jointed connecting rods j to opposite arms of a lever handle k pivoted at 7 to the
furnace front the arrangement being such that in proportion as the one h is closed
the other is opened and vice versa-This arrangement while particularly
advantageous in connection with a suction draught induced by the action of a fan
or air exhauster is also applicable to furnaces in which the draft is obtained in
other ways.
The register openings in the sliding register h are of course of such size that
when brought opposite to the front ends of the grate bars they will permit the bars
as they are reciprocated to pass in and out through them. In lieu of the Septuin
or division wall F the ordinary bridge wall may be used. But I much prefer the
former particularly in connection with the suction draft-With the ordinary bridge
wall the fuel gases are apt sometimes owing to their tendency to rise and occupy
the higher spaces of the furnace not to mingle properly with the air and thus to
pass off unconsumed. But by employing the septum or division wall the products
of combustion can escape only through the openings f(which are at about the
height of the ordinary Bridge wall) and by bringing the rear or discharge ends of

page_text: the tubular grate bars in the immediate proximity of these openings as indicated
in Figure 2 the heated air therefrom will meet and mingle with the fuel gases as
they issue from the openings funder the best conditions to insure their combustion.
In lieu of having a number of openings ƒ a continuous horizontal slot or opening
can be employed.
Taking the place of the ordinary chimney or smoke stack is a pipe or draft
flue G to which is connected a fan H worked by a sinall Engine as indicated at I
or by any other suitable motor. This fan when in action draws air through the
registers hi into and through the furnace-I would here remark that other forms
of air exhausters may be employed as for example the steam now generally used to
create the requisite draught in Locomotives But I prefer to employ the fan either
alone or in combination with other draught inducing apparatus In the flue
intermediate between the furnace and the fan is interposed a Condenser J hero
shewn as consisting of a drum provided with two screens m n and an intermediate
water distributing pipe o Upon both screens rest masses of Coke or other suitable
material. The heated air from the furnace enters below the lower screen m and
thence passes up through the mass of coke resting thereon meeting on its way the
water which is constantly discharged from the water distributor o and trickles or
filters down through the coke-The effect is to cool down the air which cooling
effect is still further enhanced by the passage of the air through the coke resting
on the upper screen n―The object however of this upper coke screen n is mainly
to prevent the air as it is drawn upward from carrying along with it out from the
Condenser any spray or particles of water. The water passing down through the
coke and heated by contact with the hot air gathers at the bottom of the Condenser
and passes off through a valve or cock controlled pipe P. The cooled air after
leaving the Condenser is drawn into the fan and discharged therefrom into the
surrounding atmosphere at r.
With a view to compactness and convenience the fan case may be arranged in
the upper part of the Condenser drum and a small Engine by which the fan is
driven be mounted upon the top of the drum as represented in figures 1 and 3.
I have described what I believe to be on the whole the best embodiment of the
Improvements I do not however restrict myself to the details herein described and
shewn in illustration of the Invention as the construction and arrangement of the
several parts may be varied without departure therefrom. But what I consider to
be novel and original and therefore claim as the Invention secured to me by the
bereinbefore in part recited Letters Patent is :-
First. The combination substantially as hereinbefore set forth of the furnace
provided with separate and distinct inlets which admit air to the furnace through
the ash pit and also at a point where it will meet the fuel gases the draught flue
the suction fan and the Condenser.
Second. The combination substantially as hereinbefore set forth of the furnace
provided with two sets of air inlets the one admitting air to the fire through the
ash pit the other conducting air to a point where it will meet the fuel gases
registers or gates for each set of inlets the suction fan and the Condenser.
Third. The combination of tubular grate bars open from end to end and con-
ducting air from the outside to a point beyond the rear wall of the fire box air
inlet passages in the ash pit and registers or gates applied to and controlling both
the open inlet ends of the grate bars and the air inlet passages in the ash pit
substantially as set forth.
Fourth-The two sets of registers and the lever handle connected to and adapted
to operate simultaneously both sets of registers in combination with the tubular
grate bars and the air inlet passages of the ash pit substantially as set forth.
Fifth. The combination substantially as herein before set forth of the fire box the
ash pit the draught or discharge flue the tubular grate bars and the perforated
septum or division wall.
Sixth. The combination with the fire box the draught flue the Condenser and
the suction fan or air exhauster of the perforated septum or division wall and

page_text: separate and distinct air channels or ducts admitting air the one to the ash pit the
other to the furnace at a point where the air will meet and mingle with the fuel
gasses passing through or issuing from the said Division wall substantially as
hereinbefore set forth.
Seventh. The fire box the draught flue the Condenser and the suction fan or air
exhauster in combination with the perforated septum or division wall the separate
and distinct air channels or ducts admitting air the one to the ash pit the other to
the furnaces at a point where the air will meet and mingle with the fuel gases
passing or issuing from the said Division wall and registers or gates for said air
channels substantially as hereinbefore set forth.
In witness whereof I the said John Henry Johnson have hereunto set my
hand and seal this twenty second day of March One thousand eight hundred
and eighty three
J. DENRY JUANDON (L.S.)
To, The Commissioners of Patents for Inventions,
I hereby grant my Fiat giving leave to the above named John Henry Johnson
to file in the Office of the Commissioners of Patents for Inventions, with the
Specification to which the same relates, the above written Disclaimer and
Memorandum of Alteration.

page_text: Filed 27th April 1883.
"
TO ALL TO WHOM THESE PRESENTS SHALL COME I JOHN HENRY
JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex Gentleman Send
Greeting WHEREAS Her Most Excellent Majesty Queen Victoria by Her
Letters Patent under the Great Seal of Great Britain and Ireland bearing date
at Westminster the 11th day of May A.D. 1882 in the forty fifth year of Her Reign
did for Herself Her heirs and successors give and grant unto me the said John
Henry Johnson my executors administrators and assigns Her special license full
power sole privilege and authority that I the said John Henry Johnson my
executors administrators and assigns or such others as I the said John Henry
Johnson my executors administrators or assigns should at any time agree with
and no others from time to time and at all times thereafter during the term
therein expressed should and lawfully might make use exercise and vend within
the United Kingdom of Great Britain and Ireland the Channel Islands and
Isle of Man an Invention of "IMPROVEMENTS IN OR CONNECTED WITH BOILER
AND OTHER FURNACES a communication to me from abroad by Edward J Mallett
Junior of the City County and State of New York in the United States of America
for and during the term of fourteen years thence next ensuing And whereas in
pursuance and performance of a proviso in the said Letters Patent contained I
the said John Henry Johnson did within Six calendar months next after the
date of the said Letters Patent namely on the 13th day of September A.D. 1882
cause a Specification in writing under my hand and seal purporting to particularly
describe the nature of the said Invention and in what manner the same was to be
performed to be duly filed in the Great Seal Patent Office And whereas since the
tiling of the said Specification I the said John Henry Johnson have ascertained that
the first fifth and seventh claiming clauses in the said Specification contained might
be held to be too broad as covering matter which was not in itself new at the date
of the said Letters Patent and I am therefore desirous of amending the said
Specification as hereinafter more fully appearing NOW KNOW YE that I the
said John Henry Johnson by and with the leave of Her Majesty's Solicitor
General and for the reason aforesaid do amend the said Specification in manner
following that is to say:-I strike out the word "or" which occurs at line 6 of
page 7 of the Queens Printers Copy of the said Specification published at the
Commissioners of Patents Sale Department in One thousand eight hundred and
eighty two and substitute therefor the word "on." I also strike out the first

page_text: claiming clause contained in lines 3, 4 and 5 of page 8 of the said Copy of the said
Specification. I also strike out the word "Second" which occurs at line 6 of the
said page 8 and substitute therefor the word "First." I also strike out the word
"Third" which occurs at line 10 of the said page 8 and substitute therefor the word
"Second." I also strike out the word "Fourth" which occurs at line 16 of the
said page 8 and substitute therefor the word "Third." I also strike out the Fifth
claiming clause which which is contained in lines 20, 21 and 22 of the said page 8.
I also strike out the word "Sixth" which occurs at line 23 of the said page 8 and
substitute therefor the word "Fourth." I also strike out the seventh claiming
clause which is contained in lines 27 and 28 of the said page 8. I also strike out
the word "Eighth " which occurs at line 29 of the said page 8 and substitute
therefor the word "Fifth." And in order that the effect of the said Disclaimer may
be clearly understood I annex hereto a Copy of the said Specification as it will
appear when so amended the preamble and testing clause being omitted.
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 N° 737 the same being
characterised mainly by the employment of distinct and separate inlets which
admit each in adjustable quantity the one inlet admitting air into the furnace at
a point where it will meet the fuel gases in conjunction with a suction fan for
inducing draught and condenser which acts to cool the heated air or gas from the
furnace at the time or before it is drawn into the fan.
to the fire through the ashpit and the other inlet admitting heated air
.
A
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 tho
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 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 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
aforesaid system of promoting the combustion of fuel in boiler furnaces the exhaust
steam which usually is employed in locomotive and other engines to create anıl
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 i 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 loco-
motives-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 fmeet 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 fin the
septum wall F and uncovers the openings 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 his 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 opeuing 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 in 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 requisito 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 openings r to meet the heated air issuing from the rear ends of
the grate bars.
8
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 a 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 8 is
also fixed a sector &' to the periphery of which is attached a chain or cord v from
which a weight w is 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 rotato in a direction to swing the damper K up far enough to
cover the openings f by which action the cord tis wound upon the end 8.
the door is again closed the cord t will be pulled and caused to unwind from the
ends 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.
When

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 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 o' 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 coils 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 the highly heated gaseous products of
combustion 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 fun 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 hinged or otherwise made inovable 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 o³ 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 a
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 on 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 sido
clevation 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 a³ to
the feed water tank which in this instance is in the tender. The pipe a² discharges
into a chamber 6 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 communicating with a suction fan H' on the rear of the tender driven by
a sinal engine L' or by any other suitable means and acting to draw air through
the tubes. The exhaust steam entering the condensing compartment b² 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 degreo 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 whero
the carriages join one another and said duct or pipe e² 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 substituto in part for the latter condenser a pneumatic
condenser similar in principle to the one herein before described. Fresh air can thus
be distributed by pipes and registers to all parts of a ship.
The condensing chamber which the exhaust steam enters is situated between
a water compartment above and a water compartment g³ below. The upper one ƒª
contains cold water; the lower one g² 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 ³ whose walls extend between
from the top to the bottom of the chamber, the sides of this box are perforated
at i for entrance of the exhaust steam. In the floor of chamber 6² are openings j
placed so as to open into both the box h³ and the chamber b³ outside and leading
into the chamber g' below. From the upper chamber f* leads a pipe terininating
in a rose k² from which water is sprayed or showered in the requisite quantity into
the said box 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 through the apertures 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 b² outside the box h³ pass down
through into the chamber g and the water is thence pumped back to the
locomotivo boiler in the usual way. I thus utilize the exhaust steam 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 combination with the septum wall and the ash pit of the damper the
fire door and means substantially as described whereby the damper is automatically
operated to close either the opening in the septum wall or the opening in the ashi
pit wall according as the door is open or shut substantially as described.
Second-The combination of tubular grate bars or otherlinlets 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 suction fan
or other air exhauster with or without the condenser substantially as described.
Third: 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.
Fourth: 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.
Fifth Apparatus for condensing exhaust steain 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 hereunto set my
hand and seal this twenty second day of March One thousand eight hundred
and eight the
Notice of the application for leave to file this Disclaimer and having been
advertized in accordance with my directions
I hereby grant my Fiat giving leave to the abovenamed John Henry Johnson 3
to file in the Office of the Commissioners of Patents with the Specification to
which the same relates the above written Disclaimer and Memorandum of
Alteration.

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
AND CONNECTED WITH BOILER AND OTHER FURNACES." A communication
from abroad by Edward J. Mallett, jun., of the city, county, and state of
New York, in the United States of America.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at the
Office of the Commissioners of Patents on the 15th February 1882.
JOHN HENRY JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman. "IMPROVEMENTS IN AND CONNECTED WITH BOILER AND OTHER
FURNACES." A communication from abroad by Edward J. Mallett junior of the
City County and State of New York in the United States of America.
The improvements constituting this Invention have reference to promoting the
combustion of fuel in boiler and other furnaces the object being to effect as far as
possible complete combustion of all the fuel gaseous as well as solid so as to utilize
the same in the production of heat.
To attain this result according to this Invention a draught is created and
maintained by an active mechanical appliance such as a fan instead of by a
chimney smoke stack or the like. This appliance acts to draw or suck the air
through the furnace in contradistinction to impelling or forcing it into the furnace.
The fan or air exhauster in thus acting necessarily will take heated (and conse-
quently expanded) air unless some means be provided by which the air can be
reduced in temperature before it reaches the fan. The objection to taking heated
and consequently expanded air into the fan aside from the fact that the heat
necessarily injures and soon destroys the fan is that the latter must necessarily be
of very much larger size and require more power to drive it than otherwise would
be the case.
For this reason there is interposed between the furnace and the fan an appliance
which may be termed a water-contact condenser through which all the air drawn
through and from the furnace passes and by which it is cooled before reaching the
Din C

page_text: fan a draught flue being provided as a communication between the furnace and
the condenser. The condenser may be made in various ways but it is preferred to
use for the purpose a vessel containing screens of Coke or other suitable material
upon which wates in comparatively small quantity is constantly discharged. The
beated air passing up through the bed of Coke is brought into direct contact with
the water trickling or filtering down through the same and by this direct contact
is cooled to the requisite extent. It is also desirable in connection with the
suction shaft to provide separate ducts or air inlets the one admitting air beneath
the grate bars in the usual way and the other admitting air at a point where it
will meet and mingle with the fuel gases and to provide in connection with these
separate inlets registers or grates by which the proportionate volumes of air
admitted at these points may be regulated and varied at pleasure I prefer to use
for this purpose tubular grate bars open at each end the outer ends as well as tho
air inlet openings in the Ash Pit are provided with registers or grates by means of
which the volume of air admitted at each of these points can be regulated with
nicity. In lieu of the ordinary bridge wall a septum or division wall is used
provided with one or more openings through which the products of combustion
pass from the fire box to the discharge flue and the inlets or ducts which supply
the air needed to effect the combustion of the fuel gases are so placed that the air
will meet and mingle with the fuel gases at the point where they pass through or
issue from the openings in the division wall the object being to compel a complete
and intimate commingling of the fuel gases with heated air whereby the combustion
of those gases is effected. The grate bars with a view to keeping them clean and
also to keeping the fire clear are so arranged as to be capable of both rotating on
their axes and reciprocating in the direction of their length. In order to thus
actuate them use is made of a key having an end of a size to fit into the grate bar
provided with laterally projecting lugs or pins adapted to enter and engage bayonet
slots in the front end of the grate bars. The stem or handle of the key is jointed
so that the outer portion of the handle may be turned to an angle to the other
part to obtain the leverage required in order to rotate the grate bar.
It is preferred to connect the two registers which regulate the air admissions
below and through the bars by means of jointed connecting rods to opposite arms
of a lever handle pivotted to the furnace front the arrangement being such that in
proportion as the one closes the other opens and vice versa. This arrangement
while particularly advantageous in connection with a suction draft induced by the
action of a fan or air exhauster is also applicable to furnaces in which the draft is
obtained in other ways.
In place of the division wall at the back of the furnace the ordinary bridge wall
may be used.
With a view to compactness and convenience the fan case may be arranged in
the upper part of the Condenser drum and a small Engine by which the fan is
driven be mounted upon the top of the drum.

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
15th August 1882.
JOHN HENRY JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman. "IMPROVEMENTS IN AND CONNECTED WITH BOILER AND OTHER
FURNACES." A communication from abroad by Edward J. Mallett junior of the
City County and State of New York in the United States of America.
The improvements constituting this Invention have reference to promoting the
combustion of fuel in boiler and other furnaces the object being to effect as far as
possible complete combustion of all the fuel gaseous as well as solid so as to
utilize the same in the production of heat.
To attain this result according to this Invention a draught is created and
maintained by an active mechanical appliance such as a fan or air exhauster
instead of by a chimney smoke stack or the like. This appliance acts to draw or
suck the air through the furnace in contradistinction to impelling or forcing it into
the furnace. The fan or air exhauster in thus acting necessarily will take heated
(and consequently expanded) air unless some means be provided by which the air
can be reduced in temperature before it reaches the fan. The objection to taking
highly heated and consequently expanded air into the fan aside from the fact that
the heat necessarily injures and soon destroys the fan is that the latter must
necessarily be of very much larger size and will require more power to drive it
than otherwise would be the case. For this reason there is interposed between
the furnace and the fan an air cooling and condensing appliance which may be
termed a water-contact condenser through which all the air drawn through and
from the furnace passes and by which it is cooled before reaching the fan a draught
flue being provided as a communication between the furnace and the condenser.
The condenser may be made in various ways but it is preferred to use for the
purpose a vessel containing screens of coke or other suitable material upon which
water in comparatively small quantity is constantly discharged. The heated air
passing up through the bed of coke is brought into direct contact with the water
trickling or filtering down through the same and by this direct contact is cooled to
the requisite extent. It is also desirable in connection with the suction draft to
provide separate ducts or air inlets the one admitting air beneath the grate bars in
the usual way and the other admitting heated air at a point where it will meet
and mingle with the fuel gases and to provide in connection with these separate
inlets registers or means by which the proportionate volumes of air admitted at
these points may be regulated and varied at pleasure. It is preferred to use for
this purpose tubular grate bars open at each end. Their outer ends as well as the
air inlet openings in the ash pit are provided with registers or gates by means of
which the volume of air admitted at each of these points can be regulated with
nicety. The two sets of registers or gates for convenience sake and to insure their
simultaneous adjustment are connected to be operated by a single lever or handle
whose movement causes the closing of one set of registers proportionately to the
opening of the other set. In lieu of the ordinary bridge wall or septum or division
wall is used provided with one or more openings through which the products of
combustion pass from the fire box to the discharge flue; and the inlets or ducts
which supply the air needed to effect the combustion of the fuel gases are so placed
that the air will meet and mingle with the fuel gases at the point where they pass
through or issue from the openings in the division wall the object being to compel
a complete and intimate commingling of the fuel gases with heated air whereby
the combustion of those gases is effected.

page_text: improvements in their preferred form.
Figure 1 is a front sectional elevation of a boiler furnace embodying the
improvements.
Figure 2 is a longitudinal vertical section of the same.
Figure 3 is a vertical central section of the condenser together with the fan and
its driving engine mounted thereon.
Figure 4 is a perspective view enlarged of the front and of one of the tubular
grate bars.
Figure 5 represents the key by which each bar may be both rotated and moved
lengthwise backwards and forwards.
A is the body of the furnace and B is the boiler. These parts may be of any
improved construction C is the ash pit and D is the fire box. The grate bars E are
metal tubes open from end to end. Their front ends are supported in and open
through the front wall of the furnace. Their rear ends extend through to the rear
of the septum or division wall F and are supported in boxes a therein. The grate
bars (with a view to keeping them clean and also to keeping the fire clear) are so
arranged as to be capable of being both rotated on their axes and of being moved
backwards and forwards in the direction of their length. In order to thus actuate
them use is made of a key G Figure 5 having an end b of a size to fit into the
grate bar provided with laterally projecting lugs or pins c adapted to enter and
engage with bayonet slots & which are formed in the front end of the grate bar as
shewn in Figure 4. The stem or handle of the key G is jointed at e so that the outer
portion of the handle may be turned to an angle with the other part to obtain the
leverage required in order to rotate the grate bar.
Air is admitted to the furnace at two points namely through the hollow grate
bars whence it is discharged in highly heated condition at a point beyond the wall F
so as to meet and mingle with the gaseous products of combustion passing through
the openings fin that wall as indicated in Figure 2 and through the openings g in
the ash pit whence it passes up between the grate bars to the fire in the usual way.
It is essential in order to secure perfect combustion to regulate the proportionate
volumes of air admitted at these two points and to this end the inlet ends of the
grate bars are provided with a sliding register h and the inlet openings g with a
like register i. It is preferred to connect the two registers h and i by means of
jointed connecting rods j to opposite arms of a lever handle k pivoted at 1 to the
furnace front the arrangement being such that in proportion as the one / is
closed the other i is opened and vice versa. This arrangement while particularly
advantageous in connection with a suction, draught induced by the action of a fan
or air exhauster is also applicable to furnaces in which the draught is obtained in
other ways.
The register openings in the sliding register h are of course of such size that
when brought opposite to the front ends of the grate bars they will permit the bars
as they are reciprocated to pass in and out through them. In lieu of the septum or
division wall F the ordinary bridge wall may be used. But I much prefer the former
particularly in connection with the suction draught. With the ordinary bridge
wall the fuel gases are apt sometimes owing to their tendency to rise and occupy
the higher spaces of the furnace not to mingle properly with the air and thus to
pass off unconsumed. But by employing the septum or division wall the products
of combustion can escape only through the openings f (which are at about the
height of the ordinary bridge wall) and by bringing the rear or discharge ends of
the tubular grate bars in the immediate proximity of these openings as indicated
in Figure 2 the heated air therefrom will meet and mingle with the fuel gases as
they issue from the openings funder the best conditions to insure their combustion.
In lieu of having a number of openings fa continuous horizontal slot or opening can
be employed.
Taking the place of the ordinary chimney or smoke stack is a pipe or draught
flue to which is connected a fan H worked by a small engine as indicated at I

page_text: or by any other suitable motor. This fan when in action draws air through the
air hi into and through the furnace. I would here remark that other forms of air
exhausters may be employed as for example the steam now generally used to create
the requisite draught in locomotives. But I prefer to employ the fan either alone
or in combination with other draught inducing apparatus. In the flue intermediate
between the furnace and the fan is interposed a condenser J here shown as consisting
of a drum provided with two screens m n and an intermediate water distributing
pipe o. Upon both screens rest masses of coke or other suitable material. The
heated air from the furnace enters below the lower screen m and thence passes up
through the mass of coke resting thereon meeting on its way the water which is
constantly discharged from the water distributer o and trickles or filters down
through the coke. The effect is to cool down the air which cooling effect is still
further enhanced by the passage of the air through the coke resting on the upper
screen -The object however of this upper coke screen n is mainly to prevent the
air as it is drawn upward from carrying along with it out from the condenser any
spray or particles of water. The water passing down through the coke and heated
by contact with the hot air gathers at the bottom of the condenser and passes off
through a valve or cock controlled pipe P. The cooled air after leaving the con-
denser is drawn into the fan and discharged therefrom into the surrounding
atmosphere at i.
With a view to compactness and convenience the fan case may be arranged
in the upper part of the condenser drum and a small engine by which the
fan is driven be mounted upon the top of the drum as represented in Figures
1 and 3.
I have described what I believe to be on the whole the best embodiment of the
improvements I do not however restrict myself to the details herein described and
shown in illustration of the invention as the construction and arrangement of the
several parts may be varied without departure therefrom. But what I consider to
be novel and original and therefore claim as the Invention secured to me by the
herein before in part recited Letters Patent is :-
First: The combination of a furnace provided with distinct and separate air
inlets which introduce air to the furnace through the ash pit and also at a point
where it will meet the fuel gases a draught flue and a suction fan by which
air is sucked or drawn into and through the furnace substantially as hereinbefore
set forth.
Second-The combination substantially as hereinbefore setforth of the furnace
provided with se arate and distinct inlets which admit air to the furnace through
the ash pit and also at a point where it will meet the fuel gases the draught flue
the suction fan and the condenser.
Third: The combination substantially as herein before set forth of the furnace
provided with two sets of air inlets the one adınitting air to the fire through the
ash pit the other conducting air to a point where it will meet the fuel gases
registers or grates for each set of inlets the suction fan and the condenser.
Fourth: The combination of tubular grate bars open from end to end and con-
ducting air from the outside to a point beyond the rear wall of the fire box air
inlet passages in the Ash pit and registers or gates applied to and controlling both
the open inlet ends of the grate bars and the air inlet passages in the ash pit
substantially as set forth.
Fifth-The two sets of registers and the lever handle connected to and adapted
to operate simultaneously both sets of registers in combination with the tubular
grate bars and the air inlet passages of the Ash pit substantially as set forth.
Sixth-The combination of a perforated septum or division wall through the
opening or openings in which the fuel gases are compelled to pass with air channels
or ducts which conduct heated air into the furnace to a point where it will meet
and intermingle with the gases passing through or issuing from the division wall
substantially as and for the purposes hereinbefore set forth.
Seventh-The combination substantially as heroinbefore set forth of the fire box

page_text: the ash pit the draught or discharge flue the tubular grate bars and the perforated
septum or division wall.
Eighth-The combination with the fire box the draught flue the condenser and
the suction fan or air exhauster of the perforated septum or division wall and
separate and distinct air channels or ducts admitting air the one to the Ash pit the
other to the furnace at a point where the air will meet and mingle with the fuel
gases passing through or issuing from the said Division wall substantially as herein-
before setforth.
R
Ninth The fire box the draught flue the condenser and the suction fan or air
exhauster in combination with the perforated septum or division wall the separate
and distinct air channels or ducts admitting air the one to the Ash pit the other to
the furnaces at a point where the air will meet and mingle with the fuel gases
passing or issuing from the said division wall and registers or gates for said air
channels substantially as hereinbefore set forth.
In witness whereof I the said John Henry Johnson have to this my
Specification set my hand and seal this twelfth day of August One
thousand eight hundred and eighty two.