Improvements in Gas Generating Furnaces or Gas Producers.
Year: 1892

page_text: Date of Application, 21st Mar., 1892
Complete Specification Left, 21st Dec., 1892-Accepted, 21st Jan., 1893
PROVISIONAL SPECIFICATION.
Improvements in Gas Generating Furnaces or Gas Producers.
I, OLIVER WILLIAM KETCHUM, Machinist, of 46 King Street West in the
City of Toronto, Province of Ontario, Canada, do hereby declare the nature of
this invention to be as follows:-
The object of this invention is to provide a simple and efficient furnace or
producer, for the generation or production of a fuel gas of uniform quality, and one
which may be run continuously for lengthened periods of time without requiring to
be stopped in order to remove ashes, clinkers, or other refuse of the fuel.
According to my invention I place above the fire-pot or gas generating furnace a
fuel reservoir which automatically supplies the fire-pot, as the fuel therein becomes
consumed. This fuel reservoir is provided with a telescopically arranged cylinder,
so that the distance from the grate in the fire-pot, to the bottom of the fuel cylinder
may be varied by lengthening or shortening the fuel cylinder.
I provide the producer with a water jacket, and the water jacket is so made as
to cause the water to circulate within it. The water jacket is substantially made
of boiler plate and capable of being used under the same pressure as a steam
boiler.
The water jacket forming the casing of the fire-pot, prevents the fuel from
adhering to the sides of the fire-pot, or forming clinkers on it, and thereby facilitates
the ready falling down of the fuel.
As the fuel descends, its moisture and volatile gases are distilled by the heat in
the furnace of the fire-pot. Air is forced into the fire-pot by means of a blower,
and thus a pressure is maintained, which forces evolved gases out through a pipe
made to convey them to the furnace, in which they are to be consumed.
The water jacket may be connected with a steam boiler, and used as a heater of
the feed water.
The fuel reservoir is made of sufficient size to hold a charge which will serve for
several hours.
It is found important then to have a grate under the fire-pot with ash-pit below,
so arranged that ashes and refuse from the fire may be effectively and easily
removed, without having to stop and withdraw the fire.
For this purpose, I use a double circular grate with a space between the two.
These grates are connected together, and can be made to revolve. They are
perforated for the passage of air, and the upper one has placed on it over the centre
a perforated cone, which admits air among the fuel, and prevents ashes from
accumulating in the centre.
The space between the two grates is divided into a number of divisions or pockets
by means of scrapers, or arms, which are fixed and do not turn when the grate
revolves.
In each grate there are two or more large openings through which the ashes may
fall. These are placed not opposite or directly over each other, so that the ashes
first fall upon the lower grate through the opening in the upper one, and as the
grates revolve, and the arms between them do not, the ashes are held by the arms,
until the opening in the lower grate comes under that division or pocket, when they
fall into the chamber below.
The friction of the fuel against the sides of the fire-pot is sufficient to prevent it
from turning bodily with the grates as they turn, hence by the turning of the
grate, the lower bed of ashes may be cut off from under the fuel and dropped into
the ash chamber.
By this means the ashes may be regularly removed, and as fresh fuel may be

page_text: added at any time my apparatus may be run continuously for long periods without
stopping the production of gas.
In some cases the ashes may be removed from the ash chamber by means of a
screw or other mechanical device.
Dated this 21st day of March 1892.
J. C. MEWBURN,
55 & 56, Chancery Lane, London, Chartered Patent Agent.
COMPLETE SPECIFICATION.
Improvements in Gas Generating Furnaces or Gas Producers.
I, OLIVER WILLIAM KETCHUM Machinist of 46 King Street West in the
City of Toronto, Province of Ontario, Canada, 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 :-
The object of this invention is to provide a simple and efficient furnace or
producer, for the generation or production of a fuel gas of uniform quality, and one
which may be run continuously for lengthened periods of time without requiring to
be stopped in order to remove ashes, clinkers, or other refuse of the fuel. The
improved furnace further enables the heat that is produced in making the gas to be
more fully utilized.
According to my invention 1 place above the fire-pot or gas generating furnace
a fuel reservoir which automatically supplies the fire-pot, as the fuel therein
becomes consumed. This fuel reservoir is preferably provided with a telescopically
arranged cylinder, so that the distance from the grate in the fire-pot to the bottom
of the fuel cylinder may be varied by lengthening or shortening the fuel cylinder.
I provide the producer with a water jacket substantially made of boiler plate and
capable of being used under the same pressure as a steam boiler. This jacket is so
constructed as to cause the water to circulate within it and the water which
is supplied through a suitable feed vessel may pass from the jacket to a steam
boiler, so that the jacket constitutes a boiler feed water heater.
The water jacket prevents the fuel from adhering to the sides of the fire-pot,
or forming clinkers on it, and thereby facilitates the ready falling down of the
fuel.
As the fuel descends, its moisture and volatile gases are distilled by the heat in
the furnace of the fire-pot. Air is forced into the fire-pot by means of a blower,
and thus a pressure is maintained, which drives out the evolved gases through a
pipe which conveys them to the furnace or other place where they are to be
consumed.
The fuel reservoir is made of sufficient size to hold a charge which will serve for
several hours.
I have a grate under the fire-pot with ash pit below, so arranged that ashes and
refuse from the fire may be effectively and easily removed, without having to stop
and withdraw the fire.
For this purpose I use a double circular grate that is to say an upper and a
lower grate with a space between the two. These grates are connected together
and can be made to revolve. They are perforated for the passage of air and the
upper one has placed on it over the centre a cone which prevents ashes from
accumulating in the centre or entering the air pipe.
The space between the two grates is divided into a number of divisions or
pockets by means of scrapers, or arms, which are fixed and do not turn when the
grate revolves.
In each grate there are one or more large openings through which the ashes may
fall. These are placed not opposite or directly over each other; the ashes
therefore first fall upon the lower grate through the openings in the upper one,
and as the grates revolve, and the scrapers between them do not, the ashes

page_text: are held by the scrapers, until the openings in the lower grate come under the
corresponding divisions or pockets when they fall into the ash chamber below.
The friction of the fuel against the sides of the fire-pot is sufficient to prevent
it from turning bodily with the grates as they turn, hence by the turning of the
grate, the lower bed of ashes may be cut off from under the fuel and dropped into
the ash chamber.
By this means the ashes may be regularly removed, and as fresh fuel may be
added at any time my apparatus may be run continuously for long periods without
stopping the production of gas.
Instead of the grates being made to revolve and the scrapers being fixed it is
obvious that the scrapers may be made to revolve and the grates be fixed.
In some cases the ashes may be removed from the ash chamber by means of a
screw or other mechanical device.
Figure 1 of the accompanying drawings is a vertical section of a gas generating
furnace or gas producer constructed according to my invention.
Figure 2 is a plan of the double revolving grate, part of the upper grate being
cut away to show the fixed scrapers and the bottom grate.
Figure 3 is on a larger scale a vertical section of the grate.
a is the gas generating furnace or fire-pot and bb is the fuel reservoir which
automatically supplies the fire-pot as the fuel therein becomes consumed. This
reservoir is preferably made telescopic so that the lower section b¹ can be raised or
lowered in order to lengthen or shorten the reservoir and thereby regulate the
distance between the grate and the bottom of the said reservoir. For the purpose
of raising or lowering the section 6' it is fitted with adjusting rods c c. d is a door
or cover to the reservoir b. f is the water jacket surrounding the fire-pot; the
water space in the jacket is divided by a concentric cylindrical diaphragm g so as to
facilitate the circulation of the water therein. The water enters the jacket by a
pipe leading from a supply vessel i and it leaves the jacket, together with any
steam generated therein by a pipe which is shown as leading to the upper part of
the vessel i. k is a pipe leading from the top of the vessel i to a steam boiler. The
vessel is supplied with water by the pipe and as the water will become con-
siderably heated in this vessel before passing to the jacket f the impurities it
contains will become deposited in the said vessel from which they can be readily
removed. m is the outlet for the gases from the apparatus. n is pipe through
which air is supplied to support combustion of the fuel in the fire-pot. This pipe
is also made to serve as a support to the centre of the grate and the scrapers.
p is the upper grate and q the lower grate both of which are carried by a central
casting supported on ball bearings ss and working against anti-friction rollers s¹ s¹.
The upper grate is formed with one or more large openings t and the lower grate
with one or more large openings u which however are not opposite or directly below
the openings t. vv are fixed scrapers or arms which divide the space between the
two grates into a number of divisions or pockets. These scrapers are carried by a
central ring w.
xx are pivoted swinging scrapers attached to the upper grate to clean
the ashes away from the lower part of the sides of the fire-pot a; y is a sweeper or
scraper attached to the lower grate in order to sweep the ashes into the ash chamber
over the screw D hereinafter described. zz are rollers supporting the outer portiou
of the upper grate. A is a worm shaft worked by hand (or other power) for
imparting rotation to the grates by gearing with a worm wheel A' formed on the
the upper grate as shown. B is a cap or cone carried by the upper grate; it
prevents ashes accumulating in the centre or falling into the air pipe n.
C is the ash chamber and D is a screw for removing the ashes therefrom.
This screw is rotated when required by means of the bevel gearing E E and hand
wheel F.
The operation is as follows:-The inner jacket ƒ and the feed vessel i having
been filled with water a fire is started on the grate p.
When this is properly ignited
the fuel reservoir bb' is filled with coal or other fuel and the door d is made secure.
Air is forced into the fire by means of the pipe n.
The carbon di-oxide formed by

page_text: the combustion of the fuel in the lower part of the fire-pot a passes up through
the deep bed of fuel and is converted into carbon monoxide or carbonic oxide gas
and the volatile gases in the fuel which is in the fuel reservoir are gradually dis-
tilled by the heat of the incandescent fuel in the fire-pot and when mixed with
the carbonic oxide form a combustible gas of uniform quality which is conveyed
away by the off-take pipe m. The fuel reservoir is of sufficient capacity to
hold a supply of fuel to last for a considerable length of time and it is renewed
from time to time as it becomes exhausted. By raising or lowering the lower
section the depth of the fuel in the fire pot is increased or decreased. This
telescopic construction of the fuel reservoir is not essential to the successful work-
ing of the gas producer, but is advantageous where different kinds and qualities of
fuel are made use of, the larger the lumps of fuel and consequent interstices the
greater should be the depth of fuel in the fire-pot for the production of a good
quality of gas. The ashes fall through the large openings of the upper grate /
upon the non-open parts of the lower grate 9 which has preferably the same
number of large openings but these are placed intermediate between those of the
upper grate. As the two grates, which are rigidly connected together, are made
to revolve by means of the worm shaft A, the fixed scrapers v hold stationary the
ashes on the lower grate until the large openings u come beneath them when they
fall into the ash pit C. The scrapers attached to the upper grate in
front of each opening t clean the ashes from the outer circumference of the grate
and force them into the said openings; these scrapers are pivoted at their front
end so as to enable them to surmount any irregularity or obstruction. The sweeper
or scraper y (there may be one or more) attached to the lower grate carries the
ashes over the screw D so that this can remove them. In cases where it is con-
venient to stop the making of gas at suitable intervals the screw D and the
scrapery can be dispensed with and the ash chamber C cleaned out by opening the
doors and removing the ashes in the ordinary way.
Figure 4 is a plan of a double grate (part of the upper grate being broken away
to show the lower grate) illustrating a modification of my invention in which
instead of the grates being made to revolve while the scrapers are fixed the grates
are stationary and revolving scrapers are used.
Figure 5 is a vertical mid section of Figure 4.
Figure 6 represents one of the outside standards for the grates and scrapers.
Letters of reference in these figures which are the same as those in Figures 1,
2 and 3 indicate corresponding parts. The scrapers between the two fixed
grates p and q are rigidly secured by the circular casting 2 to a set of scrapers v₁
placed above the grate p and the two sets of scrapers are caused to revolve by
means of the worm A gearing with a worm wheel A' composed of segmental castings
to which the outer ends of the scrapers v are fixed. The rollers 2 z support
the outer portion of the scrapers v and v¹. The ball bearings ss and anti-friction
rollers facilitate the rotary motion of the casting and scrapers. The out-
side of the grate p is made fast to the standards G that support the rolls zz and the
centre of this grate is supported by the ball bearings s s. The lower grate gis
supported at the outside by the standards G and at the centre it is secured to the
air pipe n.
Figures 7, 8 and 9 are views corresponding respectively with Figures 4, 5
and 6 and illustrating a modification which differs from that shown in Figures 4,
5 and 6 in that the lower grate y has no large openings for the ashes to fall through,
the scrapers v being of such form as to force the ashes on the lower grate y over
the rim or outside of same so that they fall into the ash chamber.
The upper scrapers shown in Figures 4, 5, 7 and 8 are not in all cases
essential. When they are not employed the ashes fall through the openings t in the
upper grate on to the lower grate by gravity alone and are removed from the lower
grate by the action of the scrapers v.
In exceptional cases a brick lined jacket can be used in place of the water
jacket f.

page_text: 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 in respect of gas generating furnaces or gas producers is :-
1. The combination substantially as hereinbefore described of an upper and a
lower grate and scrapers so arranged and working that the ashes fall through
openings in the upper grate on to the lower grate from which they are then removed
by means of scrapers so as to fall into the ash chamber as set forth.
2. The combination substantially as hereinbefore described of an automatic
feeding fuel reservoir, and of an upper and a lower grate and scrapers so arranged
and working that the ashes fall through openings in the upper grate on to the lower
grate from which they are then removed by means of scrapers as set forth.
3. The combination substantially as hereinbefore described of an upper and a
lower grate and scrapers so arranged and working that the ashes fall through
openings in the upper grate on to the lower grate from which they are removed
by means of scrapers so as to fall into the ash chamber as set forth and of a screw in
the ash chamber for removing the ashes therefrom as explained.
4. In a gas generating furnace or gas producer of the kind herein before referred
to a water jacket constructed substantially as hereinbefore described so that water
is caused to circulate and become heated therein as set forth.
5. In a gas generating furnace or gas producer of the kind hereinbefore referred
to an automatic feeding fuel reservoir made in telescopic sections so that the lower
section can be raised and lowered substantially as and for the purpose hereinbefore
described.
6. Constructing gas generating furnaces or gas producers substantially as herein-
before described and represented in the accompanying drawings.
Dated this 20th day of December 1892.
J. C. MEWBURN,
55 & 56, Chancery Lane, London, Chartered Patent Agent.