Improvements in Furnaces or Apparatus suitable for the Manufacture of Combustible Gas.
Year: 1896

page_text: Date of Application, 9th Mar., 1896
Complete Specification Left, 8th Dec., 1896-Accepted, 6th Mar., 1897
PROVISIONAL SPECIFICATION.
Improvements in Furnaces or Apparatus suitable for the Manufacture
of Combustible Gas.
I, ARTHUR KITSON, residing at Philadelphia, in the County of Philadelphia,
and the State of Pennsylvania, United States of America, Mechanical Engineer,
do hereby declare the nature of this invention to be as follows:-
This invention relates particularly to improvements in furnaces or apparatus
suitable for generating gas from fuel subjected therein to certain treatment, although
certain features of the invention are capable of application in combustion furnaces
generally. The invention herein described is specifically an improvement upon the
general type of gas producers illustrated in United States Letters Patent granted
October 17, 1893, to myself and Thomas Walker, and numbered 507,073, and has
for its object the securing to a still greater degree of the advantages designed to be
secured by said before described apparatus and the rendering of certain portions of
the apparatus more automatic, together with the simplification and reduction of
cost throughout the mechanism.
An arrangement of apparatus according to my invention is as follows:-
The furnace has a cylindrical shell which may be made of heavy sheet iron; it
is provided with a firebrick lining, constituting the walls of the combustion chamber.
The base plate of the furnace is supported upon any suitable arrangement of legs,
and the firebrick living is immediately supported by a ring which rests upon struts
or pillars above the base plate.
The upper portion of a rotating table forms the hearth which preferably has a
surface inclined from the horizontal as illustrated in Patent No. 507,073 above
referred to, and which I now provide with certain irregularities or convolutions
which further increase the disturbing action of the rotating hearth upon the charge
of fuel in the producer. A hollow shaft for supporting the rotating hearth rests
and rotates upon ball bearings. These balls roli in a circular groove in a ring-
shaped bed plate, which may be supported in any desirable way. The hollow
shaft is also provided with any number of suitable bearings to withstand side thrusts
and preserve it in a vertical position.
The rotating hearth is made ring-shaped and the central opening of said hearth
is occupied and nearly filled by a stationary central plate, which is preferably
provided with a number of radially projecting wings. Attached to the under
side of the central plate and depending therefrom, is a pipe which rests upon
any suitable foundation and supports the stationary central plate in its position.
In said pipe, or counected thereto in any desired manner, is a blowing apparatus.
This blowing apparatus may be a blowing engine, but preferably consists of
steam jet apparatus, located within the pipe. There is a horizontal ring on the
under side of the stationary plate, and a vertical ring projecting up from the
end of the pipe and co-acting with the horizontal ring to prevent any portion of
the charge from working down into the blast pipe. Two similar co-operating
rings act to prevent any portion of the charge from working down into the hollow
shaft.
A worm wheel is rigidly fixed upon the hollow shaft, and a worm co-operates

page_text: therewith to rotate the shaft and hearth; stirrups hold the worm in engagement
with the worm wheel.
An ordinary form of peep hole affords a view of the ash pit, and a scraper depends
from the under side of the rotating hearth, which, in its revolution, sweeps the
accumulated ashes into the water seal. A take-off for the gases from the combus-
tion chamber, is provided. There is an extension downward from the wall of
the combustion chamber which is preferably made in sections and fastened by
bolts, passing through elongated bolt holes to the ring that supports the fire brick
lining. A series of helical grooves are cut on the inner side of the combustion
chamber walls, and corresponding helical grooves are cut in the cylindrical outer
surface of the rotating ring-shaped hearth.
On the top of the producer a feed hopper is mounted; it is provided with a
rotating hollow charging valve of the kind described in Patent No. 507,073. The
discharge pipe beneath said hopper and charging valve is normally closed by a
charging bell of the familiar form, supported from a counter-weighted lever. This
lever is operated to depress the bell by a connection actuated through any
convenient mechanism or directly by a cam on the charging valve, or on its
shaft.
The mode of operation of my invention is as follows:-The fuel, being introduced
into the hopper, its shaft is continuously and slowly rotated. The charging valve
receives and drops upon the bell its predetermined amount of fuel. The cam then
forces down the charging bell and the fuel is spread about the combustion chamber.
The counter-weighted lever immediately lifts the bell to close the opening again on
the passage of the cam. The action of the charging bell in spreading the fuel
about the circumference of the combustion chamber is an important feature, as practice
shows that the fuel tends to bunch at the centre of the fire and thus produce an
uneven thickness which is counteracted by the above action of the bell. The worm
gearing constantly rotates the ring shaped hearth or, if desirable, reverses the same
periodically, while the central plate remains stationary and the resultant action is
to keep the body of fuel continually grinding upon itself to a much greater degree
than where the entire surface of the hearth rotates, as in Patent No. 507,073 herein-
before mentioned. The radial projecting wings before referred to intensify this
action, as do also the irregularities or flutings, which project up into the body of the
fuel and throw the zone of agitation further up into the charge, while they perform
the additional important function of preserving a non-conducting body of ashes in
the depressions between them.
The finely ground ashes sift down between the cylindrical surface of the encircling
extension of the combustion chamber walls, and the outer surface of the ring-shaped
revolving hearth. This action is accelerated and the ashes finely ground by the
roughening of the surfaces above described by cutting therein the helical grooves.
The ashes collecting in the pit on the base plate are swept around by the scraper
and periodically deposited in the water seal. Any heat retained by the ashes is
thus expended in generating steam which passes up from the water seal and assists
in the operation of the gas producer. The main portion of the steam and air
necessary for the operation of the producer is, of course forced up by the steam jet
through the pipe attached to the central plate and out through the opening between
the ring shaped hearth and the stationary plate. The gas passes off through the
take off, and the operation of the apparatus is continuous.
Of course various changes could he made in the details of my apparatus without
departing from the spirit and scope of my invention. Different shapes might be
given to the ring shaped hearth and to the stationary plate, as well as to the wings
thereon. The arrangement of bearings for the hollow shaft, and of the worm
gearing, may be changed. The mechanism for opening the charging bell might be
replaced by other apparatus operated from the shaft of the charging valve, and the
disposition of the blowing apparatus might be altered. The various modified forms
of apparatus thus produced would still, however, operate upon the same principle,
and be included in my invention. Also some of my improvements, for instance the

page_text: automatic changing device, may be used in furnaces or apparatus other than gas
producers.
Deted this Oth das of March 1806
Improvements in Furnaces or Apparatus suitable for the Manufacture
of Combustible Gas.
1, ARTHUR KITSON, residing at Philadelphia, in the County of Philadelphia,
and the State of Pennsylvania, and doing business at No. 401 Chestnut Street, in
said city, 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 particularly to improvements in furnaces for generating
gas from carbonaceous fuel subjected therein to a certain treatment, although the
apparatus herein described might be used in furnaces employed for other purposes.
The invention herein described is specifically an improvement upon the general
type of gas producers illustrated in the Specification of Letters Patent previously
granted to me and numbered 19,521 of 1893 and has for its object the securing to
a still greater degree of the advantages designed to be secured by said before
described apparatus, and the rendering of certain portions of the apparatus more
automatic in its action, together with the simplification and reduction of cost of the
mechanism.
The preferred form of the various improvements is illustrated in the accom-
panying drawings in which,
Figure 1, is a vertical section on lines 1, 1, of Figure 3.
Figure 2, is a similar vertical central section on lines 2, 2, of Fig. 3.
Figure 3, is a plan view of the base plate of the apparatus with the worm
gearing for rotating the hearth shown in dotted lines.
Figure 4, is a detail of the charging apparatus.
Throughout the drawings like reference figures refer to like parts. 1, is the
cylindrical shell of the furnace which may be made of heavy sheet iron. 2, is
the fire brick lining, constituting the walls of the combustion chamber 27.
3, is the base plate of the furnace which is supported on any suitable arrangement
of legs 4. The fire brick lining is immediately supported by ring 5, which rests
upon struts or pillars 6. 7, is a rotating hearth which preferably has the general
plane of its surface inclined from the horizontal as illustrated in the specification
above referred to, but which I now show with certain irregularities or convolutions
composed of elevations above and depressions below said general plane, which
further increases the disturbing action of the rotating hearth upon the charge of
fuel in the producer. These irregularities, convolutions or flutings are marked 8.
9, is a hollow supporting shaft for the rotating table whose upper surface forms the
hearth, said shaft resting and rotating about a vertical axis upon ball bearings 10.
These balls roll in a circular groove 11, in the ring-shaped bed plate 12, which
may be supported in any desirable way. The hollow shaft 9, is also provided with
any number of side bearings 42, to withstand side thrusts and preserve it in its
vertical position.
The rotating table or hearth 7 is made ring-shaped and the central opening is

page_text: occupied and nearly filled by a stationary central plate 13, which is preferably
provided with a number of radially projecting wings 14. Attached to the
underside of plate 13, and depending therefrom, is a pipe 15, which rests upon any
suitable foundation and supports the stationary central plate 13 in its position.
In said pipe 15, or connected thereto in any desired manner, I provide any
convenient form of blowing apparatus (not shown). This blowing apparatus may
be a blowing engine, but preferably consists of a steam jet apparatus at 16,
located within the pipe 15, and the proper steam connections for the same (not
shown). 17, is a ring on the under side of the stationary plate 13, and 18, is a ring
projecting up from the end of the pipe 15, and co-acting with ring 17, to prevent
any portion of the charge from working down into the blast pipe. 19 and 20, are
similar co-operating rings acting to prevent any portion of the charge from working
down into the hollow shaft 9.
21, is a worm wheel rigid upon shaft 9, and 22, is the worm co-operating
therewith to rotate the shaft and table or hearth 7. 23, 23, are stirrups holding
the worm in engagement with the worm wheel.
24, is an ordinary form of peep-hole affording a view of the ash pit, and 25, is a
scraper depending from the under side of the rotating hearth which in its revolution
sweeps the accumulated ashes into the water seal 26. 41 is a take-off for the
gases from the combustion chamber 27.
28, is an extension downward of the walls of the combustion chamber which is
preferably made in sections and fastened by long bolts or studs 29, passing through
the elongated bolt holes 30, to the ring 5. 39, 39, are a series of helical grooves
cut in the inner side of the combustion chamher walls 28, and 40, 40 etc., are
corresponding helical grooves cut in the cylindrical outer surface of the rotating
ring-shaped table or hearth 7. This downward extension 28 reaches below the
lowest point of the hearth and encircles and closely fits the sides of the table
which form the hearth, the opposing surfaces thus formed being sufficiently near
each other to grind the ashes which sift down between them. In practice I find a
close fit to be necessary to prevent the ashes grinding out too fast. I have shown
these opposing surfaces as cylindrical, though it might be well to have them
slightly frusto-conical so that the wear between them could be taken up by
adjusting the table to slightly higher positions, as the wearing away of the surfaces
renders the same necessary in order to preserve a predetermined distauce between
said surfaces.
31, is the feed hopper mounted on the top of the producer, and 32, is the
rotating hollow charging valve of the kind described in the specification aforesaid.
The discharge pipe beneath said hopper and charging valve is normally closed
by charging bell 33, of the familiar form, supported from the counter weight
lever 34. This lever is operated to depress the bell by the connection 35, actuated
through any convenient mechanism or directly by the cam 37, on the charging
valve 32, or on its shaft 36.
The mode of operation of my invention is as follows: The fuel, being introduced
into the hopper, the shaft 36, is continuously and slowly rotated. The charging
valve receives and drops upon the bell 33 its predetermined amount of fuel. The
cam 37, then forces down the charging bell and the fuel is spread about the
combustion chamber. The counter-weighted lever 34 immediately lifts the bell to
close the opening again on the passage of the cam. The worm gearing constantly
rotates the ring shaped hearth 7, or, if desirable, reverses the same periodically,
while the plate 13, remains stationary and the resultant action is to keep the body
of fuel continually grinding upon itself to a much greater degree than where the
entire surface of the hearth rotates, as in the apparatus described in the aforesaid
specification. The radial projecting wings 14, intensify this action, as do also the
irregularities or flutings 8, which project up into the body of the fuel and throw the
zone of agitation further up into the charge, while they perform the additional
important function of preserving a non-conducting body of ashes in the depressions
between them.

page_text: The finely ground ashes sift down between the cylindrical surface of the
encircling extension 28, of the combustion chamber walls, and the outer surface of
the ring-shaped revolving hearth. This action is accelerated and the ashes more
finely ground by the roughening of the surfaces above described by cutting therein
the helical grooves 39, and 40. The ashes collecting in the pit on the base plate 3,
are swept around by the scraper 25, and periodically deposited in the water seal 26.
Any heat retained by the ashes is thus expended in generating steam which passes
up from the water seal and assists in the operation of the gas producer. The main
portion of the steam and air necessary for the operation of the producer is, of
course forced up through the pipe 15, by the steam jet and out through the
opening between the ringshaped hearth 7, and the stationary plate 13. The
gas passes off through the take-off 41, and the operation of the apparatus is
continuous.
Of course various changes could be made in the details of my apparatus without
departing from the spirit and scope of my invention. Different shapes might be
given to the ring shaped hearth 7 and to the stationary plate 13, as well as to the
wings thereon. The arrangement of bearings for the hollow shaft 9, and of the
worm gearing, may be changed. The mechanism for opening the charging bell
might be replaced by other apparatus operated from the shaft of the charging
valve, and the disposition of the blowing apparatus might be altered. The various
modified forms of apparatus thus produced would still, however, operate upon the
same principle, and be included in my invention.
The charging bell as shown in the drawing has a greater spreading action on the
fuel than is customary and this has a special function in the particular combination
of apparatus here disclosed for the reason that I find a tendency on the part of the
fuel to gather at the centre of the revolving hearth unless special means are
taken to spread it about the circumference, and this means I provide in the
charging bell.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In a gas producer, the combination of a hearth formed by the upper surface of
a rotating table, with a combustion chamber whose walls extend downward below
said hearth, and encircle and closely fit the edges of the table, the opposing surfaces
thus formed being sufficiently near to grind the ashes sifting between them,
substantially as described.
2. In a gas producer, the combination of a hearth formed by the upper surface
of a rotating table, with a combustion chamber whose walls extend downward
below said hearth, and encircle and closely fit the edges of the table, the opposing
surfaces thus formed being sufficiently near to grind the ashes sifting between, one
or both of said opposing surfaces being roughened, substantially as described.
3. In a gas producer, the combination of a hearth formed by the upper surface
of a rotating table, with a combustion chamber whose walls extend downward
below said hearth, and encircle and closely fit the edges of the table, the opposing
surfaces thus formed being sufficiently near to grind the ashes sifting between
them, and one or both of the opposing cylindrical surfaces thus formed being
roughened by the formation of helical grooves therein, substantially as described.
4. In a gas producer, the combination of a hearth formed by the upper surface
of a rotating table mounted on a vertical axis, the general plane of said upper
surface being inclined to the horizon, but diversified by elevations above and
depressions below said general plane, a combustion chamber whose walls extend
downward below the lowest point of said hearth, and encircle and closely fit the
edges of the table, together with mechanism for rotating said hearth, substantially
as described.
5. In a gas producer, the combination of a hearth formed by the upper surface
of a rotating table_mounted on a vertical axis, the general plane of said upper

page_text: surface being inclined to the horizon, but diversified by elevations above and
depressions below said general planę, a combustion chamber whose walls extend
downward below the lowest point of said hearth, and encircle aud closely fit the
edges of the table, together with mechanism for rotating said hearth, and one
or both of the opposing surfaces formed by the downwardly extending walls of
the combustion chamber and the edges of the table being roughened, substantially
-as described.
6. In a gas producer, the combination of the rotating, ring-shaped hearth formed
by the upper surface of a rotating, ring-shaped table, the combustion chamber
whose walls extend downward below said hearth and closely fit the edges of the
table, the opposing surfaces thus formed being sufficiently near to grind the ashes
sifting between them, the stationary central plate nearly filling the opening in said
ring-shaped table, and mechanism for rotating said ring-shaped table, substantially
as described.
7. In a gas producer, the combination of the rotating, ring-shaped hearth formed
by the upper surface of a rotating, ring-shaped table, the combustion chamber
whose walls extend downward below said hearth and closely fit the edges of the
table, the opposing surfaces thus formed being sufficiently near to grind the ashes
sifting between them, the stationary central plate nearly filling the opening in said
ring-shaped table, and mechanism for rotating said ring-shaped table, together with
radially projecting wings on said central plate, substantially as described.
8. In a gas producer, the combination of the rotating, ring-shaped hearth formed
by the upper surface of a rotating, ring-shaped table, the combustion chamber
whose walls extend downward below said hearth and closely fit the edges of the
Lable, the opposing surfaces thus formed being sufficiently near to grind the ashes
sifting between them, the stationary central plate nearly filling the opening in said
ring-shaped table, and mechanism for rotating said ring-shaped table, together with
a pipe attached to and depending from the under side of said plate, a blast
producing mechanism, and connections therefrom to said pipe, substantially as
described.
9. In a gas producer, the combination of the rotating, ring-shaped hearth formed
by the upper surface of a rotating, ring-shaped table, the combustion chamber
whose wails extend downward below said hearth and closely fit the edges of the
table, the opposing surfaces thus formed being sufficiently near to grind the ashes
sifting between them, the stationary central plate nearly filling the opening in said
ring-shaped table, and mechanism for rotating said ring-shaped table, together with a
pipe attached to and depending from the under side of said plate, and a blast
producing mechanism, located in said pipe, substantially as described.
10. In an automatic charging device the combination of the hopper, the hollow
charging valve, the bell closing the discharge pipe from said charging valve, the
pivoted counter weighted lever which normally holds said bell in position to close
said discharge pipe, the cam on the valve shaft and connecting mechanism whereby
said cam oscillates the counter-weighted lever to automatically lower the bell
after the charge has been deposited thereon by the charging valve, substantially as
described.
11. The furnace hearth formed by the combination of a ring-shaped table
rotating on a vertical axis, the general plane of the upper surface of said table
being inclined to the horizon and the stationary central plate, nearly filling the
opening in said ringshaped table, together with mechanism for rotating said
ring-shaped table, substantially as described.
12. The furnace hearth formed by the combination of a ring-shaped table
rotating on a vertical axis, the general plane of the upper surface of said table
being inclined to the horizon and the stationary horizontal central plate, nearly
filling the opening in said ring-shaped table, together with mechanism for rotating
said ring-shaped table, substantially as described.
13. The furnace hearth formed by the combination of a ring-shaped table
.rotating on a vertical axis, the general plane of the upper surface of said table

page_text: being inclined to the horizon, but diversified by elevations above and depressions
below said general plane, and the stationary central plate, nearly filling the-
opening in said ring-shaped table, together with mechanism for rotating sail.
ring-shaped table, substantially as described.
1004
For the Applicant,
W. LLOYD WISE,
46 Lincoln's Inn Fields, London, W.C., Chartered Patent Agent..