Improvements in and relating to Spark Arresters.
Year: 1898

page_text: Date of Application, 21st June, 1898-Accepted, 27th Aug., 1898
COMPLETE SPECIFICATION.
Improvements in and relating to Spark Arresters.
I, THOMAS THORSON, of Brownton, in the County of Green and State of
Wisconsin, United States of America, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
-
My invention relates to improvements in spark arresters designed for use on
steam boiler furnaces generally, although it is more particularly adapted for use
in connection with traction engines; and the object that I have in view is to
provide a structure which will effectually extinguish the sparks, collect the
cinders and at the same time provide the necessary draft to the furnace flues and
smoke box to maintain combustion of the fuel in the grate chamber.
A further object of the invention is to provide a spark arrester which may be
readily cleansed of the cinders that accumulate therein; and furthermore, I aim
to simplify the construction, provide for its ready application to a thrashing
engine and promote the efficiency in the operation of the structure.
With these ends in view, the invention consists in the novel combination of
elements and in the construction and arrangement of parts, which will be herein-
after fully described and claimed.
To enable others to understand the invention, I have illustrated different
embodiments thereof in the accompanying drawings, forming a part of this
specification, and in which,
Figure 1 is a vertical sectional elevation through a traction engine with my
improved spark arrester applied thereto.
Figure 2 is a vertical transverse section through a part of the improvement
and the smoke box of the portable engine, the plane of the section being indicated
by the dotted line 2-2 of Figure 1.
Figure 3 is a vertical cross section somewhat similar to Figure 2, but illustra-
ting a slightly modified arrangement of the spark arresting appliances on the
portable engine.
Figure 4 is a vertical sectional elevation of another modified embodiment of
the spark arresting appliance in which the suction fan is arranged for rotation
in a horizontal plane and on a vertical axis.
Like numerals of reference denote like and corresponding parts in each of the
several figures of the drawings.
In order that others skilled in the art may understand the nature of my
improved spark arrester, I have illustrated the same applied to a portable engine
in the several figures of the drawings, but it will be understood that no novelty
for the engine per se is herein claimed and that I do not confine myself to the
employment of the spark arrester in this particular type of engines, because I
reserve the right to apply the arrester to any style of steam boiler furnace to
prevent the escape of sparks therefrom. The numeral 1 designates the boiler
of a thrashing engine, 2 are the smoke flues therein, 3 is the smoke box, and 4 is
an engine shaft.
Erected vertically on the forward end of the engine boiler is a short vertical
DQ17

page_text: smoke stack 5, which is suitably united to the boiler suell and which communi-
cates directly with the smoke-box 3 therein. The upper end of this smoke stack
is designed to be closed by a suitable cover or head, 10, when the engine boiler
is in service and the suction fan of the spark arrester is positively driven; but this
cover or head 10 is removably secured in place to the upper end of said short smoke
stack 5 for the purpose of permitting the escape of the smoke and products of
combustion from the boiler when the fire is started therein or when the fan of
the spark arrester is at rest.
6 designates a fan drum or casing which is suitably attached either to the
short smoke stack or the boiler shell in any suitable way, and this fan casing
communicates with the short smoke stack 5 at a point intermediate of the height
of the latter through an opening or port 6, located centrally with respect to the
casing or drum so that the products of combustion may be drawn when the fan is
in motion from the smoke stack 5, into the drum or casing 6. In the opposite head
of the fan drum to the port 6ª which establishes communication between said drum
and the smoke stack 5, there is provided an air inlet port 7 which is normally
closed by means of regulating slides or doors 8, suitably supported on the outer
side of the fan drum so as to be within convenient reach of the engine attendant.
These regulating slides or doors may be fitted to the fan drum to slide thereon
across the opening 7, or said doors 8 may be hinged or pivoted to the fan drum
to be adjusted across the air opening 7. Under normal conditions the slides or
doors 8 remain closed and the fan is adapted to create the draft through the furnace
and exhaust the products of combustion from the smoke box and stack to the
fan drum; but to regulate the draft through the furnace, the slides or doors 8
may be opened more or less to admit atmospheric air to the fan drum at the eye
of the rotary fan therein. The admission of atmospheric air to the fan at the
axial line of its drum or casing decreases the draft through the furnace by
reducing the strength of the suction or current created by the rotary action of
the fan, and thus my appliance is made to serve as a draft regulator for the engine
furnace as well as a spark arrester to prevent the escape of live sparks from the
furnace. This fan drum or casing, 6, terminates in a discharge mouth or
nozzle 9 which faces toward the rear end or grate chamber of the engine, and
from one side of the fan drum extends a frame 11 which serves to support the
shaft of the rotary fan. In Figures 1 and 3 of the drawings, this frame is shown
as extending from the fan drum on the opposite side to the short smoke stack 5,
and said frame may be of any suitable construction and attached to the fan drum
by any approved means. The frame is constructed with aligned shaft bearings, 12,
arranged in the plane of the axis of the fan drum 6, and in these bearings is
journaled the shaft 13 of the rotary fan 14. The inner end of this fan shaft 13
extends through the air inlet opening 7 of the fan drum so as to terminate within
the drum, and to said end of the fan shaft is rigidly secured the hub of the
rotary fan, the latter being of any desired construction approved by those skilled
in the art. The bearings 12 on the supporting frame 11 are spaced apart a suit-
able distance for the fan shaft, 13, to receive the driving pulley 15, around which
passes an endless belt that is driven from a pulley on the engine shaft 4, or from
any other suitable shaft of the traction engine.
16 designates a water tank which is placed upon the boiler of the traction engine,
and this tank may simply rest upon the boiler or it may be removably secured
thereto by bolts or clamps. The water tank 16, is adjacent to the fan drum, 6,
and preferably extends lengthwise of the engine boiler, and at one end this water
tank is constructed with an elbow 17, that extends upwardly to the discharge
nozzle or mouth 9, of the fan drum. This elbow of the water tank is operatively
connected with the mouth of the fan drum in a detachable manner for the purpose
of permitting the water tank to be uncoupled from the fan drum so as to enable
the attendant to gain access to the interior of the water tank and clean the cinders
which accumulate in said tank; and in the embodiment of the invention shown.
the connection of the water tank to the fan drum is effected by an union or coup-

page_text: ling 18 of any preferred construction. The end of the water tank distant from
the connection of said tank to the fan drum is closed and to this closed end of the
tank is attached a smoke-stack 22, which is somewhat longer than the smoke
stack 5.
Within the water tank between its communication with the fan drum and the
rear smoke stack 22 is a series of baffles or deflectors arranged in zigzag order to
give to the products of combustion a tortuous or sinuous course through the
water tank, whereby the live sparks conveyed by the escaping products of com-
bustion are caused to impinge against the baffles and to be precipitated into the
water which is contained in the lower part of the tank to the level indicated by
the line referred to on the drawings as the "water line." A series of three baffles
or deflectors is provided within the water tank, and of these baffles the first one 19
is arranged adjacent to the elbow 17 and depends from the upper side of the
water tank to terminate on a line above the water level in said tank. The second
baffle 20 is fixed to the bottom of the water tank at a suitable distance from the
baffle 19, and it extends upwardly from the tank bottom to terminate a suitable
distance below the top of said tank, while the third baffle 21 is situated at a suit-
able distance from the second baffle 20 and adjacent to the long smoke stack 22,
said third baffle 21 depending from the top of the water tank and terminating at
its lower edge on the plane of the corresponding edge of the baffle 19, and at a
suitable distance above the water level. The baffles on the top and the bottom
of the tank are thus disposed in alternate or zigzag relation to form a continuous
smoke passage through the water drum and which compels the escaping products
of combustion to pursue a sinuous course through said water tank.
As the pro-
ducts of combustion traverse the smoke space of the water tank, the sparks and
cinders carried thereby impinge against the series of baffles which arrests the
progress of the sparks and cinders and insures their precipitation into the water
contained in the lower part of the tank 16, and thus the sparks and cinders are
extinguished and caused to accumulate in the water chamber of the tank 16,
from whence they may be removed at any time by disengaging the tank 16 upon
proper adjustment of the union or coupling 18. In the embodiment represented
by Figure 3 of the drawings the fan drum or casing is disposed at one side of the
vertical plane of the short smoke stack 5 and the smoke passage through this
stack 5 is continuous or uninterrupted. The object in locating the fan drum and
the parts associated therewith is to position the drum away from the boiler of the
portable engine and not expose the fan and the devices associated therewith to
the intense heat from the smoke box.
The spark arrester shown by Figures 1 to 3 inclusive, contemplate the employ-
ment of a fan rotating in the vertical plane on a horizontal axis, but this is not
strictly necessary, because the fan may be arranged to rotate in a horizontal plane
and about a vertical axis as shown by Figure 4. In this embodiment of the inven-
tion the fan drum is arranged in a horizontal position and the supporting frame
for the fan shaft assumes a vertical position above the drum, which at its lower
side communicates directly with the short stack or trunk which is in communica-
tion with the smoke box of the boiler. The fan drum is coupled with the elbow
of the water tank which, at its other end, communicates with the smoke stack,
and between the fan drum and the elongated smoke stack are the series of baffles
which intercept the sparks and cinders to deflect the same into the water contained
within the tank.
In the operation of my spark arrester, the fan is driven positively by suitable
power connections with the engine on which the spark arrester is installed, and
said fan rotates in a direction to force the current into the nozzle or mouth of
the drum. The rotation of the fan creates a suction through the furnace, and
this suction may be regulated by adjusting the wind slides or doors.
exhausted products of combustion are forced by the fan through the tortuous
smoke space of the water tank and they find their exit through the elongated
smoke stack.
The

page_text: I am aware that changes in the form and proportion of parts and in the details
of construction may be made by a skilled mechanic without departing from the
spirit or sacrificing the advantages of the invention, and I therefore reserve the
right to make such modifications as clearly fall within the scope of the invention.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:
1. The combination with a smoke box of a boiler furnace, of a positively driven
rotary fan communicating directly with said smoke box, a water chamber
operatively connected with the fan casing and provided with baffles which impart
a tortuous course to the escaping products of combustion which are forced there-
through by the action of the fan, and a smoke stack communicating with the
smoke space of said water tank, substantially as described.
2. In a spark arrester, a water tank provided with a series of battles arranged
in alternate relation to each other to form a tortuous or zigzag smoke chamber
above the water line in said tank, in combination with a suction fan operatively
connected with a boiler furnace and with said water tank, and a stack communica-
ting with the smoke space of the water tank at the opposite end from the
connection of said tank with the fan drum, substantially as described.
3. The combination with a short smoke stack communicating with a boiler
furnace, of a fan drum communicating directly with said short smoke stack,
a positively driven fan operating in said casing or drum, a water tank communica-
ting with the fan drum and provided with the baffles, and a smoke stack
communicating with the smoke space of the water tank, substantially as described.
4. The combination with a smoke stack in combination with a boiler furnace,
of a fan drum connected directly to said smoke stack and provided with a valve
controlled inlet, a water chamber communicating with the outlet of the fan drum
and provided with the baffles, and an elongated smoke stack communicating
with the smoke space of said water tank, substantially as described.
5. The combination with a fan drum in communication with the smoke space
of a boiler furnace, of a water chamber separate from the fan drum and provided
with internal baffles forming a tortuous smoke space therein, means for detachably
uniting the water tank to said fan casing, a smoke stack in communication with
the water tank, and a positively driven fan mounted in the fan casing, substan-
tially as described.
Dotad this 20th dow of Lun 1000
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.