Improvements in Pottery Kilns.
Year: 1894

page_text: Date of Application, 20th Feb., 1894
Complete Specification Left, 1st Nov., 1894-Accepted, 1st Dec., 1894
PROVISIONAL SPECIFICATION.
Improvements in Pottery Kilns.
I, JOHN HAWTHORN of 554, Perry Street, Trenton, in the County of Mercer
and State of New Jersey, United States of America, Kiln Builder, do hereby
declare the nature of this invention to be as follows:-
My invention relates to improvements in that class of kilns which are used for
baking pottery, and the object of my invention is to produce a kiln which is of
simple construction and is adapted to apply hydrogenous heat to the pottery which
is being baked. It is customary to bake the pottery by means of a carbonaceous
heat which causes the biscuit or body portion of the pottery and the glazed portion
to be heated with different effects, so that the pottery when completed is crazed or
crackled. This is owing to the hard nature of the heat, but by combining hydrogen
with the carbonaceous heat so as to generate hydro-carbon gas, a more intense but
yet inilder heat is produced, which thoroughly bakes the pottery but leaves it
perfectly smooth and moreover the arrangement which I employ for generating the
hydro-carbon gas and applying it, causes a great saving of fuel.
The furnace is preferably of a circular shape when viewed in cross-section, and
has a dome like top which terminates at its upper end in the chimney, there being
in the outer lower portion of the furnace the fire-boxes and flues leading to the
baking chamber, and the chamber being provided with the usual hollow floor
which connects with the fire-boxes. The chamber is also provided with substan-
tially the usual top which is perforated for the passage of a portion of the smoke,
and with a main smoke flue or outlet which is controlled by a damper which is
provided with a chain or its equivalent extending upwards and outwards through
the furnace wall and hanging down within easy reach, so that the damper may be
operated by properly manipulating the chain. On each side of every fire-box there
are horizontal openings, which form a part of the steam flues hereinafter described,
in which are received removable pans or drawers in which water is placed to
generate steam, the water being supplied to these pans by means of a pipe which
encircles the furnace and is connected with a source of supply and provided with
cocks by means of which the supply may be adjusted so as to exactly compensate
for the evaporation in the pans. The openings merge at their rear ends in zig-zag
flues which are made in the wall of the furnace and each flue terminates at its
upper and inner end in the hollow bridge wall of the adjacent fire-box, which
bridge wall is provided with numerous jet-opening's delivering into the rear end of
the fire box at a point adjacent to the lower end of the flue.
When the furnace is used, the pans are opened so as to receive water from the
cocks and this also admits air to the flues so that sufficient oxygen may be provided
to combine with the steam and the gases of the coal, to form a hydro-carbon gas.
The heat from the fire boxes generates steam in the pans and the steam and air
flow together through the flues and by the time the steam and air has reached the
bridge walls the steam will have become superheated and will be ejected in jets
into the rear, end of the fire box, thus mingling with the gases of the coal at points
near the flues, so that an intense heat is generated and is delivered through the
said flues into the baking chamber. As the fire gets hotter, a greater amount of
heat is generated and the steam and air, acting as described, cause a great saving
of fuel and for this reason the furnace may be made with a smaller dome and
chimney, as less draught is required than in the ordinary coal burning furnace.
The hydrogen combined with the carbon of the coal, as specified, acts mildly

page_text: on the pottery so that the latter is thoroughly baked, without being crazed or
crackled.
Dated this 20th day of 1904
J. HAWTHORN,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.
COMPLETE SPECIFICATION.
Improvements in Pottery Kilns.
I JOHN HAWTHORN, of 554 Perry Street, Trenton, in the County of Mercer
and State of New Jersey, United States of America, Kiln Builder 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 :-
My invention relates to improvements in that class of kilns which are used for
baking pottery, and the object of my invention is to produce a kiln which is of
simple construction and is adapted to apply hydrogenous heat to the pottery which
is being baked. It is customary to bake the pottery by means of a carbonaceous
heat, which causes the biscuit or body portion of the pottery and the glazed portion
to be heated with different effects, so that the pottery when completed is crazed or
crackled. This is owing to the hard nature of the heat, but by combining hydrogen
with the carbonaceous heat so as to generate hydro-carbon gas, a more intense but
yet milder heat is produced, which thoroughly bakes the pottery but leaves it
perfectly smooth, and moreover, the arrangement which I employ for generating
the hydro-carbon gas, and applying it causes a great saving of fuel.
To this end my invention consists of certain features of construction, and
combinations of parts, as will be hereinafter described and then pointed out in the
claims.
Reference is to be had to the accompanying drawings forming a part of this
Specification, in which similar figures of reference indicate corresponding parts in
all the views.
Figure 1 is a vertical section of a furnace showing my improvements, on the
line 1-1 in Figure 2;
Figure 2 is a sectional plan view on the line 2-2 of Figure 1 ;
Figure 3 is an enlarged detail sectional perspective view illustrating the
arrangement of one of the fire boxes, and the flue which conveys the steam to the
fire boxes to form hydro-carbon gas; and
Figure 4 is a vertical section on the line 4-4 of Figure 1, and illustrates the
zigzag course of one of the steam flues.
The furnace 10 is of the usual exterior appearance, being preferably of a circular
shape when viewed in cross section, as in Figure 2, and having the dome-like top 11
which terminates at its upper end in the chimney 12. At necessary intervals in
the outer lower portion of the furnace are the fire-boxes 13 which are of substan-
tially the usual kind, and from the rear ends of the fire-boxes, flues 14 lead in the
usual way to the baking chamber 15, which is provided with a suitable door 16 to
enable the pottery to be placed in the furnace and removed, and the chamber has
the usual hollow Hoor 15" which connects with the fire-boxes so as to be sufficiently
heated. The above arrangement is substantially of the usual kind and forms no
part of my invention.
The chamber 15 is also provided with substantially the usual top 17 which is
provided with perforations 18 through which a portion of the smoke may pass, and
with a main smoke flue or outlet 20 which is controlled by a damper 19, which is
provided with a chain 21 or its equivalent, extending upward and outward through

page_text: the furnace wall and hanging down within easy reach so that the damper may be
operated by properly manipulating the chain.
On each side of every fire-box 13 are horizontal openings 22 which form a part
of the steam flues hereinafter described, in which are received removable pans or
drawers 23 in which water is placed to generate steam. The water is supplied to
these pans by means of a pipe 25, which encircles the furnace and is provided with
cocks 24 by means of which the supply may be adjusted so as to exactly compensate
for the evaporation in the pans. The pipe 25 is supplied by means of the pipe 26
connecting with a source of water supply; and while the arrangement of pipes
described is preferably employed, the water may be supplied to the pans in any
other convenient way, without departing from the principle of my invention.
The openings 22 merge at their rear ends in zigzag flues 27 which are made in
the wall of the furnace, and each flue terminates at its upper and inner end in the
hollow bridge wall 28 of the adjacent fire-box 13, which bridge wall is provided
with numerous jet openings 29 delivering into the rear end of the fire-box at a
point adjacent to the lower end of the flue 14. The furnace is provided with the
usual sight holes 30 so that the interior of the baking chamber may be observed.
When the furnace is used, the pans 23 are opened so as to receive water from the
cocks 24 and this also admits air to the flues 27 so that sufficient oxygen may be
provided to combine with the steam and the gases of the coal, to form a hydrocarbon
gas. The fire-boxes 13 are provided with coal in the usual way, and the heat from
these boxes generates steam in the pans 23, and the steam and air flow together
through the flues 27 and by the time the steam and air has reached the bridge
walls 28, the steam will have become superheated and will be ejected in jets into
the rear end of the fire-box, as shown in Figure 3, thus mingling with the gases of
the coal at points near the flues 14, so that an intense heat is generated and is
delivered through the said flues into the baking chamber 15.
As the fire gets hotter, a greater amount of heat is generated, and the steain and
air acting as described, cause a great saving of fuel, and for this reason the furnace
may be made with a smaller dome and chimney, as less draft is required than in
the ordinary coal burning furnace. The hydrogen combined with the carbon of the
coal as specified, acts mildly on the pottery, so that the latter is thoroughly baked
without being crazed or crackled.
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. A pottery kiln, comprising a furnace having a suitable baking chamber, fire-
boxes arranged around the furnace, and connecting by flues with the baking
chamber, zigzag flues connecting with the outer air and provided with jet openings
delivering into the fire-boxes, and evaporating pans arranged in the flues, substan-
tially as shown and described.
2. The combination with the furnace, the fire-boxes and the hollow bridge walls
of the boxes, the bridge walls having jet openings delivering into the fire-boxes, of
flues connected with the outer air and with the hollow bridge walls, and evaporating
pans held in the flues, substantially as shown and described.
3. The combination with the furnace, the fire-boxes, the zigzag Hues in the
furnace walls, and the evaporating pans arranged in the outer ends of the flues, of a
water supply pipe adjacent to the furnace, and cocks on the pipe arranged to deliver
into the evaporating pans, substantially as shown and described.
Dated this 1st day of November 1894.
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.