IMPROVEMENTS IN STEAM BOILER FURNACES, AND IN APPARATUS CONNECTED THEREWITH
Year: 1877

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
" IMPROVEMENTS IN STEAM BOILER FURNACES, AND IN APPARATUS CONNECTED
THEREWITH." A communication from abroad by Benjamin Hershey, of Erie,
Pennsylvania United States of America.
PROVISIONAL SPECIFICATION left by the said William Robert Lake at the
Office of the Commissioners of Patents on the 15th March 1877.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN STEAM BOILER FURNACES,
AND IN APPARATUS CONNECTED THEREWITH." 'A communication from abroad by
Benjamin Hershey, of Erie, Pennsylvania, United States of America.
This Invention relates to improvements in steam boiler furnaces, and the grates
for the same, and in apparatus for creating and supplying a blast to such furnaces
for supporting combustion in the same, as more fully herein-after set forth.
In the ordinary furnaces constructed with combustion chambers having flat grates,
the least inequality in the depth of fuel or unevenness in the size of the lumps of
coal, makes it easier for the air supply to pass through in some portions of the bed
than in others. The natural result is that much air enters the chamber that does
not properly (support combustion. This loss can only be obviated by constant
watching, raking, and dressing the bed of fuel. One evil attending this course is
the admission through the open doors of a large amount of cold air which checks
instead of assisting in producing steam. Another evil is that the raw fuel is thrown
immediately into the burning mass, thus for a time tending to cool it, while a large
per-centage of the gases first set free escape unconsumed, unless there is provision
made for the combustion thereof. Another disadvantage ordinarily existing in such
combustion chambers is, first, the opportunity afforded for the heated gases to pass
immediately from the place of ignition into the flues, and thence escaping; and,
secondly, the largeness of the chamber wherein the heat is not intensified in effective-
ness, being by compulsion brought in close contact with the surface to be heated.
Furthermore, in the furnace as heretofore constructed much difficulty has been
experienced in rivetting and caulking the plates composing the water legs to the

page_text: boiler proper, owing to the necessarily limited space between the flues formed by
such water legs, rendering the boiler costly in its original construction, and its
repair almost impossible. My Invention is designed particularly to obviate the
above-named objections, and also to provide for the economical and convenient
employment of liquid fuels for such furnaces, and to secure a more perfect com-
bustion of the fuel therein.
The said Invention comprises various improvements, according to which I
combine with an inner and an outer water chamber, the former constituting the
fuel receiver, an inner and outer grate, and chamber water legs and side flues formed
between said water chambers.
The inner grates are arranged in inclined positions with respect to the lower
portions of the inner water chamber, and comhined for use with bottom or side
grates arranged in the proper relation to the outer water legs, the side flues, and
the fuel chamber.
I combine with the fuel chamber formed by the inner water legs and the grates,
having the relation thereto herein stated, a central cross rock bar, whereon the fuel
is supported, prepared, and fed down between the grates and the inner water legs,
and I combine with the side flues and the grates a rear diving flue. The inner
water chamber has top and bottom horizontal end extensions combined with the
outer water chamber and diving flue. The aforesaid cross bar is arranged to have
a rocking motion between said inclined grates. The said cross rock bar has recessed
sides to receive the upper ends of the inclined grates. These inclined grates are
operated upon the pivot bars by incans of an upper centre cross bar, by which they
are also freely supported.
I use in a boiler furnace a detachable inner water leg section, adapted to be
secured within the combustion chamber of the furnace, and connected with the outer
water legs and boiler. Also a hydrocarbon receptacle, having a series of passages
surrounding it for admitting air to support combustion of the fuel. The central
hydrocarbon receptacle and compartments at its side are provided with air passages.
In combination with the fire-chamber I arrange flues at each side of the same,
and the central hydrocarbon receptacle and surrounding air passages and compart-
ments at each side, provided with air passages leading to a blast chamber below
the saine. For supplying air to the furnace grates I employ a "blower" having
direct and controllable connection with the exhaust steam pipe, the steam boiler,
and the ash-pit chamber. This blower is combined with the exhaust steam pipe
and the furnace chamber. I also combine with the boiler, furnace, and the exhaust
steam pipe an air chamber and a blower, having a clear space at their open junction
ends, into and through which the supply of air is made by the force of the steam.
And I combine with the air chamber and the furnace an exhaust steam pipe, the
blower, cylinder, and a cone.
I sometimes employ a double blower, consisting of inner and outer cylinders, an
annular space, an outer cone, and a steam pipe connecting tha same with the boiler.
And I may use a blower and an air chamber formed with a clear air space, and
connected with each other, the furnace, and the exhaust steam pipe.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Robert Lake in the Great Seal Patent Office on the 15th
September 1877.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, and Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN STEAM BOILER FURNACES,
AND IN APPARATUS CONNECTED THEREWITH." A communication from abroad by
Benjamin Hershey, of Erie, Pennsylvania, United States of America.
This Invention relates to improvements in steam boiler furnaces, and the grates

page_text: for the same, and to apparatus for creating and supplying a blast to such furnaces
for supporting combustion in the same, as more fully herein-after set forth.
In ordinary furnaces constructed with combustion chambers having flat grates,
the least inequality in the depth of fuel or unevenness in the size of the lumps of
coal, makes it easier for the air supply to pass through in some portions of the bed
than in others. The natural result is that much air enters the chamber that does
not properly support combustion. This loss can only be obviated by constant
watching, raking, and dressing the bed of fuel. One evil attending this course is
the admission through the open doors of a large amount of cold air which checks
instead of assisting in producing steam. Another evil is that the raw fuel is thrown
immediately into the burning mass, thus for a time tending to cool it, while a large
per-centage of the gases first set free escape unconsumed, unless there is provision
made for the combustion thereof. Other disadvantages ordinarily existing in such
combustion chambers are, first, the opportunity afforded for the heated gases to
pass immediately from the place of ignition into the flues and thence escaping; and,
secondly, the chamber is so large that the heat is not intensified in effectiveness,
being by compulsion brought in close contact with the surface to be heated.
Furthermore, in the furnaces as heretofore constructed much difficulty has been
experienced in rivetting and caulking the plates composing the water legs to the
boiler proper, owing to the necessarily limited space between the flues formed by
such water legs rendering the boiler costly in its original construction, and its
repair almost impossible. My Invention is designed particularly to obviate the
above-named objections, also to provide for the economical and convenient employ-
ment of liquid fuel for such furnaces, and to. secure a more perfect combustion of
the fuel therein.
The said Invention comprises the combination with an inner and outer water
chamber (the former constituting a fuel receiver) of inner and outer grates relatively
situated in respect to each other, is herein-after set forth.
Also the combination of an inner and outer water chamber and inner and outer
grates relatively situated with regard to the water legs, as herein-after set forth.
It also comprises the combination with side flues formed by the water legs and
the grates of a rear diving flue leading to the exit or chimney of the furnace,
and an inner water chamber having top and bottom horizontal end extensions
combined with an outer water chamber and a rear diving flue, as herein-after
specified.
Also constructing the inner water legs which form the top and front of the fuel
chamber in an independent single section, which can be properly fitted within the
interior of the furnace, and connected to the outer water legs and boiler proper by
means of suitable pipes, as herein-after set forth.
It also comprises a compound grate composed of two inclined grate sections in
combination with two horizontal grate sections located in the lower part of the fire
chamber; the highest portion of the inner or inclined sections stand about on a
level with the lower portions of the inner water legs or walls of the fuel chamber
proper, forming a breaker to support and disintegrate the superincumbent mass, and
give it a tendency to move down upon the inclined sections, which form a junction
with the outer or horizontal sections, whereon the fuel is finally deposited. The
inclined sections at their upper ends rest against and are supported by a central
breaker, bar, or section which, as well as the other sections of the grate, is capable
of a vibratory motion, as herein-after set forth.
It also comprises a peculiar grate receptacle for the fuel employed in a fluid state,
consisting of a hollow chamber of fire-brick or other refractory material. The
upper side of the said hollow chamber is divided into three compartments, the
central compartiment being designed for the reception of the fuel, the others being
perforated and communicating with an air space connected with a suitable blast
apparatus. The central compartment or fuel receptacle is provided with similar
apertures around its edge, and the whole is adapted to be placed in the lower part
of the fire-chamber of a furnace, and operated as hercin-after specified.

page_text: It further comprises a "blower," in which the steam from the exhaust or the
boiler is caused to act by suitable pipes and open cylinders through a clear and
unobstructed space, within which the air is taken to furnish the supply under the
grates. The cylinders of the blower are not open at both ends, but only at their
junction ends, so that the blower may be said to be formed of two parts, namely,
an inner open air chamber and an open blower, and these parts are combined in
such manner and with the steam pipes as to produce highly satisfactory results.
In the accompanying Drawings,
Figure 1 is an elevation, partly in section, of a boiler furnace embracing my
Invention; Figure 2 is a longitudinal section thereof.
Figure 3 is a view showing a partial front elevation and transverse vertical
section of my improved furnace as arranged for burning fluid or gaseous fuel.
Figure 4, a perspective view of the grate for burning liquid or gaseous fuel.
Figure 5 is a longitudinal vertical section of the furnace showing the improved
grate.
Figure 6 is a transverse section of the said furnace and grate.
Figure 7 is a perspective view of my improved grate detached from the furnace.
Figure 8 is a perspective view of a modification of my improved grate.
Figure 9 is an elevation of my improved blower, and Figure 10 is a central section
of the same.
A represents a boiler which may be of the ordinary construction, and having
water legs B; it is suitably supported upon a brick foundation, and provided with a
dome, from which a pipe or pipes may connect with heating coils or otherwise, and
having a rear opening, through which the products of combustion pass away.
An inner chamber C is arranged within the outer one, but its water legs D are
shorter than the outer ones, and it forms the fuel chamber proper, having an
opening E, through which coal is introduced. These two chambers are joined (in
Figures 1 and 2) by a front extension Fat the top of the inner chamber, to afford
a free escape of the steam generated within the walls of the inner chamber, while
the front and rear extensions G and H at its lower portion afford means for com-
munication and water circulation between the two chambers; these connections
serve as fastenings for the inner chamber. By this combination I obtain certain
highly desirable results, which a flat grate is inadequate to produce. Centrally with
the inner chamber and at or nearly on a level with its lower portion, a bar I is
longitudinally arranged upon pivots J, so that it may be rocked; it is of angular
form, to adapt it as a rocking breaker for the body of the coal which it supports.
In conjunction with this breaking bar downwardly-inclined grates K, K, are
arranged on each side thereof, being suitably pivoted in frames at a point nearly on
a level with the lower portion of the outer water legs, and so that the lower ends of
their bars shall be about on a vertical line with the outer walls of the inner water
chamber, while from the lower ends of these grates I arrange side grates L, L, which
extend to and join the inner walls of the outer water legs in horizontal positions, so
that these grates not only bear relation to the fuel chainber but to the flues M, M,
formed between the water legs of the two chambers. By this relative arrangement
of the water legs and the grates it will be seen that the distance from the lowest part
of the inner water chamber at N, and the side grate is greater than that between the
point N and the grate K. I therefore have a comparatively thin body of coal upon
the grate proper, and at the points of draught, as the coal will be inclined upon the
grate surfaces, while the supply may partly or entirely fill the chamber above the
breaking bar. This arrangement gives a large disproportion between the actual
grate surface and the area of opening through which the draught can pass directly
into the flues surrounding the inner water chamber. The object of this arrangement
is to obtain a slower circulation of the air through the burning fuel, while it compels
the more thorough mingling of the products of combustion and diminishes the
escape without having aided in the production of heat. The draught is directed
through the grates to the side flues, at which point the combustion is never deadened;
by supplying coal as the latter feeds down from the supply in a condition to produce

page_text: the best effect, the centre breaking bar, the inclined and side grates, all performing
their proper functions only in their relation with the water legs and the side flues.
The breaking bar may be wholly of iron, or partly of iron, shielded with fire-brick
to prevent it from being burnt out readily.
At the back of the inner water chamber a diving flue P is formed by means of
two vertical partitions Q, Q, seen in Figure 2, the object of which is to cause the
draught to rise over the inner water chamber, and then descend to the exit flue.
These partitions in the side flues form barriers to the direct escape of the heat, while
the flue which they form makes a place for the sparks, from which they may be
drawn by a suitable opening.
The upper edges of the inclined grates rest upon and against the sides of the
breaker bar, and for this purpose the latter is recessed to allow the bar to be rocked
without disturbing the connection therewith of the grates; the recessed bearing
sides of the rock bar are of such form as to serve as cans or lifters, which as the bar
is rocked lift and shake the inclined grates upon their lower pivoted bars. The ridge
rocker bar therefore supports the body of the coal above the grate, prepares the coal
and feeds it upon the grates, and forms the shaker for the inner grates.
In the grate, as represented in Figures 1 and 8, the ridge rocker is constructed
with inclined slotted sides, and in place of the inclined grates are substituted inclined
solid plates, which may be of metal, fire brick, or other refractory material.
The bottom or side grate bars L and the cross rock bar I are connected by a
shaker bar R by joint connections, so that the grates can be shaken together and
with equal movement to discharge the ashes and feed the coal down to the
grates.
This part of the said Invention effects a material saving of fuel, the smoke and
gasos being quite consumed by reason of the special matters which I have pointed
out.
To obviate the difficulty of riveting and caulking the plates composing the water
legs, I prefer to construct the inner water legs which form the top and front of the fuel
chamber in an independent section; this section can be fitted properly within the
interior of the furnace, and connected to the outer water legs and boiler proper by
means of suitable pipes, as more fully herein-after set forth. In this modified form
of the said furnace, the inner water legs D are constructed of an independent section
of wrought iron, the front part of the said section forming when in place the front
of the furnace, and being provided with an opening or door E for charging the
furnace with fuel. The said inner water leg section is so constructed and arranged
that it may be secured by means of stays A¹ within the combustion chamber proper,
resting upon the brick work or walls which support the furnace at each end when
in place, and leaving a flue or flues all round its outer walls and the inner legs of the
outer water legs and boiler proper.
Figures 3 and 4 illustrato a inodification whereby the said furnace is adapted to
burn liquid or gaseous fuel.
In this modification I employ for the fuel a peculiar grate and receptacle, consisting
of a hollow chamber of fire-brick or other refractory material D¹. The upper side of
the said hollow chamber is divided into three compartments E, F, G, the central
compartment being designed for the reception of the liquid or gaseous fuel, which
is supplied from a proper reservoir or source through a pipe H. The side compart-
ments are perforated as shown at E and communicate with an air space below, which
is connected with a suitable blast apparatus by means of a pipe entering at the
aperture I. The central compartment is provided with apertures around its walls,
which also communicate with the air spaces below, and the whole is adapted to be
placed in the lower part of the fire chamber in such a position that the liquid fuel,
which may consist of any of the liquid hydrocarbons or any inflammable gas, may be
admitted to the central compartment and ignited, a blast of air being introduced
through the perforations to support the combustion of the fuel.
The proper supply of air to the furnace grates is a matter of great importance, and
for this reason I employ an apparatus which I call a "blower," and which m

page_text: connected either directly with the engine or with the boiler, or with both. The
special adaptation of this apparatus not only produces the best results in giving the
proper supply of heated air to the fuel for combustion, but such supply is evenly
imingled with steam or vapor to increase combustion. The said "blower" is of
simple construction, and can be conveniently applied to marine or locomotive boiler
furnaces.
A distinguishing feature of this part of my Invention is embraced in the employ-
ment of a "blower" in which steam from the exhaust or the boiler is caused to act
by suitable pipes and open cylinders through a clear and unobstructed space, within
which the air is taken to give the supply under the grates. The cylinders of the
"blower" are not open at both ends, but only at their junction ends, so that the
blower may be said to be formed of two parts, namely, an open air chamber and an
open "blower," and these two parts are combined in such manner with the steam
pipes as to produce highly satisfactory results.
A very marked advantage of my "blower" consists in its adaptation for containing
the supply of air to the furnace when the engine is not running by opening the
blower connection direct with the boiler.
Two cylinders form the "blower;" one of these is larger than the other and forms
the air chamber, while within the smaller one the steam is caused to act. These
two cylinders are not joined, but form an open junction at their open ends. This
junction may be a telescoping one, in which the open ends of the "blower"
may be
extended within the open end of the air chamber, or they may be slightly separated.
In either case the effect is the same in leaving an open space through which the air
is supplied to the air chamber and from thence to the furnace. This space is formed
by the difference in the diameters between the two cylinders, as shown, but it may
be obtained in any other way. The outer ends of these two cylinders are closed, in
order that one may form the air chamber and the "blower." A small pipe extends
through the air chamber, past its open end, and into the "blower." This pipe
connects with the exhaust and delivers the exhaust steam directly against a cone or
deflector fixed to the inner side of the closed end of the "blower;" the effect of this
arrangement is to turn back the steam through the open end of the "blower" and
through the clear space into and through the air chamber. This nir chamber
connects by suitable pipes with the ash-pit chamber; the steam therefore passing
into and through the air chamber must draw in the air through the open junction
space and force it into the furnace to assist and keep up a proper combustion. The
open junction space must of course be sufficient to admit the required quantity of
air, and its area may be increased or diminished if found necessary in a manner well
understood. The cone stands in such relation to the open end of the exhaust steam
pipe as to give the best effect; the direction of the steam from the blower and the
drawing of the air into the air chainber are indicated by the arrows.
The aforesaid blower as described is complete in connection with the exhaust, but
this form does not permit any increase of the power of the "blower," which is often
very desirable. For this reason I inake the "blower" a double one by adapting it
for direct use with the boiler. This result I accomplish by combining an outer with
the inner blower, that is to say, I form the "blower" with a double cylinder, with
an annular space between the two parts and an end chamber, the outer cylinder
being longer than the inner one, and like the latter having a closed end and an open
end; the former is connected by a pipe directly with the boiler, and, entering the
head space between the two closed heads, delivers the steam upon a cone or deflector
secured to the outer side of the inner head, and preferably just opposite to the inner
cone, so that the steam is forced out through the annular space of the double blower
and past the clear open space into the air chamber. By these means I can not only
increase the force of the draught of the furnace, but the volume of the air and the
steam in the combustion chamber. The head space and the annular chamber may
be suitably proportioned, and the open end of the outer cylinder should terminate
with that of the inner one, and both should be in the proper relation to the "take
in" air space.

page_text: The principle upon which the air is drawn into and forced through the long
chamber is made clear by the Drawings, and the steam acting upon the body of the
air contained in the supply chamber drives it into the chamber under the grates, the
steam mingling with the air and assisting combustion. The relative lengths and
diameters of the air supply chamber and the "blower" may be as shown, or
according to any other suitable proportion.
By lengthening the air chamber, and dividing that portion of the exhaust pipe
passing through it into smaller and longer tubes, a considerable amount of hot water
from condensed steam may be saved for re-use, while at the same time the air will
be proportionately heated by the increased heating surface. The amount of air
admitted to the grate may be regulated by suitable valves.
The double construction of the "blower" affords the advantage of keeping up the
fire and air supply whether the engine is running or not. The boiler pipe connection
with the said blower is provided with valves or cocks, by which to let on or cut off
the steam.
It will be observed that the exhaust steam pipe enters the closed head of the air
chamber at or near the point at which the air is forced from the said chamber into
the ash-pit, thus obtaining the best effect from the heat.
Having thus fully described the said Invention as communicated to mo by my
foreign correspondent, and the manuer of performing the same, I wish it understood
that I claim,
First. The combination with an inner and an outer water chamber (the former of
which constitutes the fuel receiver) of the inner and outer grates arranged in relation
to the chamber water legs as above set forth and for the purpose specified.
Second. The combination with an inner and outer water chamber and inner and
outer grates arranged in relation to the water legs, as herein set forth, of the side
flues formed between the said water chambers, as described.
Third. The inner grates arranged in inclined positions with respect to the lower
portions of the inner water chamber, and combined for use with bottom or side grates
located and arranged with relation to the outer water legs, the side flucs, and the fuel
chamber, as above described.
Fourth. The combination with the fuel chamber formed by the inner water legs
and the grates, having the relation thereto herein specified of a central cross rock
bar, whereon the fuel is supported, prepared, and fed down between the grates and
the inner water legs, as above described.
Fifth. The combination with the side flues and the grates arranged in relation
thereto, as described, of the rear diving flue as above set forth and for the purpose
specified.
Sixth. The inner water chamber having the top and bottom horizontal_end
extensions, and combined with the outer water chamber and diving flue, as abovo
described.
Seventh. The combination of parts comprising the inclined grates, the cross bar
arranged to have a rocking motion between said inclined grates, the bottom side
grates, and the inner walls of the inner water legs, and the inclined grate operated
upon the pivot bars by means of an upper centre cross bar, all as above set forth and
for the purpose specified.
Eighth. In a boiler furnace a detachable inner water leg section adapted to be
secured within the combustion chamber of the furnace, and connected with the outer
water legs and boiler, as above described.
Ninth. The combination with the fire chamber of a furnace of a hydro-carbon
receptacle, having a series of passages surrounding it for admitting air to support
the combustion of the fuel, and the compartments at the side or sides provided
with air passages, some of which lead to a blast chamber, as above set forth.
Tenth. For supplying air to furnace grates a "blower" having direct and con-
trollable connection with the exhaust steam pipe, the steam boiler, and the ash-pit
chamber, and combined with the exhaust steam pipe and the furnace chamber, all as
above described.

page_text: Eleventh. The combination with a boiler furnace and the exhaust steam pipe of
an air chamber and a blower having a clear space at their open junction ends, into
and through which the supply of air is effected by the force of the steam, as above
described.
...
Twelfth. The combination of parts comprising the air chamber, the furnace, the
exhaust steam pipe, the blower cylinder and its cone, arranged in relation to each
other, substantially as above described.
Thirteenth. The combination with the air chamber and the furnace of the double
blower, consisting of the inner and outer cylinders, the annular space, the outer cone,
and the steam pipe connecting the same with the boiler, as above described and for
the purpose specified.
Fourteenth. A blower and an air chamber formed with the clear air space, and
connected with each other, the furnace, and the exhaust steam pipe, as above described
and for the purpose specified.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Eleventh day of September, in the year of our Lord One
thousand eight hundred and seventy-seven.
A