Improvements in Method of and Apparatus for Promoting Consumption of Fuel.
Year: 1893

page_text: Date of Application, 15th Aug., 1893-Accepted, 20th Jan., 1894
COMPLETE SPECIFICATION.
Improvements in Method of and Apparatus for Promoting
Consumption of Fuel.
I, JOHN Y. SMITH, of Doylestown, County of Bucks, State of Pennsylvania,
United States of America, Gentleman, do hereby declare the nature of this
invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:
This invention relates to an improved method of and apparatus for promoting
the consumption of fuel particularly applicable to locomotive boilers in which an
intermittent exhaust or blast is relied on to create the desired draft through the
bed of fire in the fire box.
It has for its objects to promote combustion, prevent the formation of clinker
and increase the steaming capacity or efficiency of the boiler.
To these ends it consists primarily in an improved method of manipulating the
fuel while being burned and further in certain novel details of construction and
combinations and arrangements of parts of the apparatus for carrying the method
into operation all as will be now described and pointed out particularly in the
appended claims.
In the accompanying drawings,
Figure 1 is a longitudinal section through a locomotive boiler with which my
present invention may be carried into effect.
Figure 2 is a half section and half elevation of the exhaust mechanism.
Like letters of reference in the figures indicate the same parts.
In the ordinary operation of locomotive boiler furnaces and for that matter other
boilers and furnaces, it is well known that there is a constant accumulation of
clinker due to the agglutination of the partially melted residuum of the fusible coal
ashes, which clinker is a constant source of annoyance, for besides the injury to the
grate and fire box, it causes the bed of fire to cake, interrupting the draft and
requiring the constant attention of the fireman to break up the cake and keep the
grate free.
Now I have discovered that if the fuel be kept in a constant state of agitation
while undergoing combustion and at the same time a powerful draft is maintained
the particles of silicious matter in the coal or the ash which ordinarily vitrify to
form clinker are broken up into minute particles or are prevented from aggluti-
nating or of agglomerating with the particles of coal or other matter to form clinker
and are carried off out of the fire box and discharged with the lighter waste
products of combustion.
By this means then the substances which form the clinker and which are ordinarily
discharged through the grate, are caused to travel in the opposite direction, i.e., up
away from the fire and out through the exits provided for the lighter products of
combustion.
In carrying the new idea into practical operation I make use of an exhaust
apparatus of a construction to be presently specifically described and which
operating intermittingly will draw the fuel from the grate surface to a considerable
distance when the full force of the exhaust is exerted, and during the intervals of
rest, allow the same to fall nearly or quite back, thus keeping the fuel in constant
agitation or so to speak, dancing on the grate, but in no instance is the exhaust
strong enough or prolonged enough to carry the fuel up, out of the fire box or allow
it to rest in a solid body long enough to cake or the clinker to vitrify and run or
agglutinate.
In carrying my invention into practice, I divide the exhaust from each cylinder
into a series of blasts acting successively and each strong enough to raise the

page_text: fuel (or in actual practice a portion of the fuel) a slight distance the effect
being then for the first blast from the exhaust to raise the fuel and as the force of
the blast lessens it drops back part way when the next portion or blast of the
exhaust comes into action raising it still further, then it again drops back a short
distance until the last portion of the exhaust acts and raises it to its greatest
height:
The interval between the cylinder exhausts is long enough for the fuel to drop
quite back to the body of the fire or grate, but is so short owing to the prolonged
action just described that it has no time to set or cake, hence is readily raised again
by the action of the next exhaust.
Referring now to the drawings, in which a mechanism especially adapted for
carrying my invention into practice is shown, the letter A indicates the boiler shell
having the usual fire tubes B, fire box C, fore end D and smoke stack D¹.
The fire box is of a construction adapted to prevent the ready escape of the
particles of fuel and to create an exceedingly high temperature at a point above
the fuel, so as to entirely burn all available heat producing products as the particles
are carried away from the body of fuel, for which purpose the bridge wall C' is
located at the rear end of the fire box with its upper portion inclined from a point
below the lowermost flue so as to leave a gradually diminishing space from a point
well up in the fire box down to said lowerinost flue. The height of this bridge wall
should be proportioned to the draft created through the fire box and it should be
high enough to prevent any of the fuel being drawn over the same when the draft is
at its maximum.
In addition to the inclined bridge wall I preferably employ a series of tiles c
resting on the inclined water tubes c' passing through the fire box, and leaving a
relatively narrow opening between the front ends of said tiles and the base of the
bridge wall as shown by the arrow with a wide opening in rear of the tiles, as
shown by the arrow c³; the effect of which is, to produce an eddy or space
through which there is a less powerful draft immediately below the edge of the
bridge wall and through which it would be difficult for any of the heavy fuel
particles to pass.
In addition to the bridge wall and inclined tiles with spaces in front and rear of
the same, any of the well known expedients may be employed for increasing the
heat generated within the fire chamber or facilitating the feeding of the
fuel, etc., etc., such for instance as the deflector plate C².
At the front of the fire box air enters ducts B³ which are preferably provided
to supply an additional quantity of air, which passing up immediately adjacent the
bridge wall serves to protect the same in a measure from the injurious effects of the
products of combustion and excessive heat to which it is subjected. The body of
cooler air forms a film as it were over the inner surface of the bridge wall and
flows away over the top of the same.
In the fore end or smoke box I locate the exhaust or intermittent draft creating
apparatus, together with the necessary mechanism for controlling the draft through
the fire box in a proper manner to secure the results before mentioned.
The ejector or exhaust apparatus proper receives the steam Irom the respective
cylinders through the divided passage e in the base E, which latter, is adapted to
seat and be bolted in the smoke box in the ordinary manner, and from the base
of the ejector, the steam is conveyed and discharged through nozzles acting
successively or at different levels upon the volume of air travelling from the
fire pot through the exhaust apparatus and out through the stack thus giving
the column of air an intermittent movement. The slow and fast movements follow.
each other with great rapidity.
To secure the best results the combined areas of the exhaust nozzles is preferably
slightly less than that of each branch of the divided passage, but the areas of the
divided passages, is greater than that of the exhaust ports the tendency of which
construction is to prolong the action of each cylinder discharge and lessen materially
the interval of rest between each cylinder discharge.

page_text: The base E which is preferably cast in one piece is provided with a central
nozzle F of relatively small area and discharging vertically from the divided
passage.
Lateral passages G enter the base from opposite sides combining in a single
central duct G' immediately over the small nozzle F, said central duct being of
relatively large area and terminating in a nozzle y at a point some distance above
the base section.
The top section which is also preferably cast integral seats upon the base section
and surrounds the duct G¹ being itself formed with ducts H H¹ terminating
respectively in nozzles h h¹. The ducts H H register at the bottom with the
divided passage e on opposite sides and the upper section is provided with induction
openings I preferably located immediately over the induction openings G, said
induction openings I passing into an annular opening i located between the
ducts H H and opening between the nozzles h h into what might be termed a
mingling chamber, the effect of which is that products, gases, etc., drawn into the
duct through the openings G are acted upon first by the steam escaping from the
nozzle F by which they are given an impetus and then by the steam escaping
through the nozzle H', g by which they are given another impetus, then combining
with products entering the openings I travel upward and are given a third impetus
by steam escaping through the nozzle h.
The combined body of upwardly rushing air and steam enters the smoke stack D¹
carrying with it a large proportion of the products from the smoke box and ejecting
the same high above the locomotive.
To prevent the accidental escape of any sparks or heavy cinders a netting K is
passed across the upper portion of the smoke box immediately below the top of the
exhaust pipe and the openings I and G are also covered by a screen, the latter
opening G being covered by simple concavo convex screen plates K'.
Around the upper openings I is an inverted conical deflector M, the smaller end
of which rests on the flange of the upper section of the exhaust pipe and from its
upper edge, which it will be noted is some distance above the openings I a screen M¹
extends in an inclined direction up to the body of the exhaust pipe. This
deflector M draws the lighter smoke gases down and further serves to equalize the
passage of the products through the fire tube or distributes the draft so to speak
from the top to the bottom; and with a view to further increasing this effect, a
deflector N extends from the front plate of the boiler above the flues, out around
the exhaust pipe above the netting M to a point near the front of the smoke box.
The deflector N is inclined downward slightly and its forward end n is given a
decided downward inclination with a view to projecting any heavy particles not
broken or comminuted by contact therewith down to the bottom of the
smoke box.
In front of the fire tubes and between the front plate of the boiler and exhaust
apparatus is arranged a damper plate O having a series of horizontal independently
operated dampers P thereon any one or more of which may be opened to regulate
the passage of the products through the flues and govern to a certain extent the
portion of the grate surface through which the greater amount of air shall pass.
In operation, the successive cylinder exhausts each being subdivided into
successive blasts, causes the column of air travelling through the grate, fire pot,
flues and stack to have a rapid intermittent movement and the blast and parts are
so regulated and proportioned that the fuel or a large portion of it at the top or
hottest portion of the fire will be kept in a constant state of violent agitation and
the ashes of the consumed particles of fuel are comminuted by abrasion against
other particles or by the air acting against the same and converted into a fine
powder which is then taken through the flues and ejected from the smoke stack
together with the lighter waste products. This fine ash dust containing this
silicious matter which ordinarily melts and forms clinkers, floats readily through
the upper hot portion of the fire box aud escapes as described, while the heavier
particles of fuel drop back during the intervals between the successive blasts,

page_text: hence the latter are never carried out of the fire box without having the portions
capable of being converted into heat effectually consumed.
It will be observed that the bridge wall serves to determine the height to which
the fuel must be raised before it can be carried over into the flues, that is to say, it
operates to elevate the passage through which the products of combustion leave
the fire box and enter the flues, and unless the draft at any time is of sufficient
strength and duration to both raise and carry the unconsumed particles over the
bridge wall, they cannot escape from the fire chamber.
Now the internitting pulsations are sufficient to raise these finer particles of
unconsumed fuel, but the duration of individual pulsations in proportion to their
strength, is too short to carry the particles over the bridge wall, consequently
they are alternately elevated and dropped, only the finer particles or ash-dust
being carried over.
The power of the exhaust increases as you approach the exhaust pipe, hence
the ash-dust when it passes the bridge wall is borne with increasing speed by the
gaseous matter and is carried into the exhaust pipe and discharged through the
smoke stack.
The deflecting plate N aids this action by directing the gaseous products and
the ash-dust towards the inlets of the exhaust pipe, thus preventing the ash-dust
from settling in the smoke box as it might otherwise do if the gaseous products
carrying the ashdust were permitted to diffuse throughout the smoke box and form
eddies in the upper part of the latter.
When the engine or locomotive is at rest or running with steam shut off I design
to maintain the draft by means of supplemental nozzles fed directly from the boiler,
which nozzles I locate preferably at the bottom and top of the exhaust pipe. By
reference to Figure 2 it will be seen that the nozzle is formed with an internal
annular chamber R having discharge openings r at the top and the nozzle / has a
central annular chamber S provided with discharge openings s at the top. These
chambers are connected respectively by branch pipes T with a pipe U leading from
the boiler. In the pipe U-cock V is located adapted to be controlled by a
longitudinal rod W extending back into the cab.
It is obvious that the engineer might be relied upon to open this cock when the
engine was at rest, but to ensure this the adjustable end w of the rod W is located
in position to be struck by the throttle lever X when the latter is moved to shut off
the supply of steam to the cylinders, thereby making it impossible for the engineer
to cut off the supply of steam from the cylinders without also opening the supply
to the supplemental nozzles.
The end wis made adjustable in order to vary the extent to which the cock is
opened by the movement of the throttle lever as will be readily understood.
The supplemental nozzles themeselves are preferably made separate and
independent of the exhaust pipe proper in order that nozzles of different
diameter may be substituted or new nozzles inserted when the old ones are worn
or injured.
Actual practice has demonstrated that while there is very little clinker producing
material left in the fire box when my present invention is carried into practice, still
there is comparatively little discharge from the smoke stack which will be carried
back into the train and this I attribute to the fact that the ash and other particles
are reduced to such an impalpable powder that when they are violently ejected from
the stack they arise with the gases and lighter products and float in the air until
the train has passed.
It is obvious that the successful embodiment of this invention leads to the most
important practical results inasmuch as the labour entailed upon the fireman and
engineer is greatly lessened and the steaming capacity or efficiency of the
locomotive materially increased.
By the employment of the supplemental nozzles which are brought into operation
whenever the cylinder exhausts are cut off, the interior of the pipe is kept free
from all deposit and what is of equally great importance by maintaining the draft

page_text: through the exhaust pipe the fine ashes etc., are prevented from working back
beneath the valves a trouble which has heretofore been deemed unavoidable.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:
1. The herein described method of promoting combustion consisting in maintaining
the fuel in a state of agitation by means of an intermittent draft, the maximum
power of which is sufficient to raise said fuel, but the duration too short to
carry the fuel out of the fire box and the minimum power of which is insufficient to
maintain the fuel above the body of the fire; substantially as described.
2. The combination with a locomotive boiler having the fire pot and bridge wall
within the fire pot extending up in front of the flue, of an exhaust pipe having
exhaust nozzles arranged to act successively with column of air whereby fuel
is raised from the body of the fire by each successive impulse but is prevented
from escaping from the fire pot into the flues by the bridge wall; substantially
as described.
3. In an exhaust apparatus, the combination with the exhaust pipe having the
steam passages and nozzles with the lateral upper and lower openings of the
screens enclosing the lower openings, the inverted cone surrounding the upper
openings and the screen closing the space between the upper edge of the cone
and body of the pipe.
4. In an exhaust apparatus, the combination with the smoke box, the exhaust
pipe located therein having the lateral air openings at the bottom, of the deflector
plate N, located between the top of the exhaust pipe and lateral air openings,
substantially as described.
5. In an exhaust apparatus, the combination with the smoke box, the exhaust
pipe having the lateral air openings therein and the inverted screen covered cone
enclosing the said openings, of the deflector plate N located between the top of the
cone and end of the pipe; substantially as described.
6. In an exhaust apparatus, the combination with the fire box, the exhaust pipe
located therein having lateral air openings, and the inverted screen covered conc
enclosing said openings of the inclined deflector N and the screen K located
between the top of the cone and end of the pipe.
Dated this 15th day of August. 1893
W. P. THOMPSON & BOULT,
Agents for the Applicant.