Improvements in Furnaces, and in Rocking Grate Bars for the same.
Year: 1896

page_text: 2
Date of Application, 28th July, 1896
2000
PROVISIONAL SPECIFICATION.
Improvements in Furnaces, and in Rocking Grate Bars for
the same.
I, ANDREW PILLATT, of the Firm of A. Pillatt and Company, of Queen's
Road Works, Queen's Road, in the Town and County of the Town of Nottingham,
Furnace Engineers, do hereby declare the nature of this invention to be as
follows:-
My invention relates to improvements in furnaces, for burning any kind of solid
fuel with but little loss, and whereby all the gases are consumed and consequently
a smokeless chimney attained, the furnace being, at the same time, durable, easily
managed, and readily cleaned.
For the purposes of my invention, I employ hollow furuace bars having lateral
openings or air inlets situated in the web at suitable distances apart, said air inlets
having their mouths towards the ash pit. The longitudinal passage through the
bar conducts the heated air, entering it from the said lateral air inlets, to the back
of the furnace bridge where it meets the flame and gases, and causes complete
combustion. Above or between the air inlets, at each side of the bar, I form teeth
er projections of approximately the same width as the bar, the teeth on one side of
the bar being preferably in line with the spaces on the other side of the bar. At
the back of the furnace, under the bridge, is placed a support in or upon which the
bars can rock, a similar support being likewise provided at the front of the furnace.
Above and below the front of the passage through the bar, I arrange cylindrical
pins or projections, the upper pin on each bar forming the pivot on which the bai
rocks. The lower pin works in a connecting bar which unites all the bars at the
trout of the furnace, and extends to any convenient position where it may be
attached to a hand-lever working on a quadrant, or equivalent device, for
imparting a rocking or oscillating motion to the bars simultaneously. The teeth
are so constructed that those of one bar fit into the spaces of the next, leaving a
clearance sufficient to admit the proper draught to the fire, and they are so shaped
that the clearance remains approximately the same in any position to which the
bars are rocked, the amount of clearance depending more or less on the fineness of
the fuel to be burned.
Instead of employing cylindrical pins on the bars, I may rock the bars by means
of projections on the connecting bar fitting or taking against each bar.
The improvements herein. described are applicable to marine, locomotive,
portable-engine and other furnaces, and permit of all clinkers and refuse material
from the fire being broken up by crushing them between the teeth of the bars.
Dated this 28th day of July 1896
ERNEST DE PASS,
Chartered Patent Agent,
78, Fleet Street, London, and 54, Market Street, Nottingham,
Agent for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Furnaces, and in Rocking Grate Bars for
the same.
I, ANDREW PILLATT, of the Firm of A. Pillatt and Company, of Queen's
Road Works, Queen's Road, in the Town and County of the Town of Nottingham,
Furnace Engineers, 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, reference being had to the accompanying
drawings and to the letters and figures marked thereon, that is to say:-
My invention relates to improvements in furnaces for burning any kind of solid
fuel with but little loss, and whereby all the gases are consumed and consequently
a smokeless chimney attained, the furnace being, at the same time, durable, easily
managed, and readily cleaned.
For the purposes of my invention, I employ hollow furnace bars having lateral
openings or air inlets situated in the web at suitable distances apart, said air inlets
having their mouths towards the asb pit. The longitudinal passage through the
bar conducts the heated air entering it from the said lateral air inlets to the back
of the furnace bridge, where it meets the flame and gases, and causes complete
combustion..
Above, or between, the air inlets at each side of the bar, I form teeth or
projections, preferably also hollow, of approximately the same width as the bar, the
teeth on one side of the bar being preferably in line with the spaces on the other
side of the bar. At the back of the furnace, under the bridge, is placed a support,
in or upon which the bars can rock, a similar support being likewise provided at
the front of the furnace. Above and below the front of the passage through the
bar, I arrange cylindrical pins or projections, the upper pin on each bar forming
the pivot on which the bar rocks. The lower pin works in a connecting bar which
unites all the bars at the front of the furnace and extends to any convenient
position, where it may be attached to a hand-lever working on a quadrant, or
equivalent device, for imparting a rocking or oscillating motion to the bars
simultaneously. The teeth are so constructed that those of one bar fit into the
spaces of the next, leaving a clearance sufficient to admit the proper draught to the
fire, and they are so shaped that the clearance remains approximately the same in
any position to which the bars are rocked, the amount of clearance depending more
or less on the fineness of the fuel to be burned.
Instead of employing cylindrical pins on the bars, I may rock the bars by means
of projections on the connecting bar fitting or taking against each bar.
And in order that my invention may be readily understood, I will proceed to
describe the same fully with reference to the accompanying drawings, in which:-
Fig. 1 is a longitudinal section of a furnace constructed according to my invention
and provided with my improved rocking fire bars.
Fig. 2 is a plan of one of my said bars, formed of two lengths.
Fig. 3 is a plan of the grate surface, showing a number of my improved fire-bars
combined.
Fig. 4 is an underside view, Fig. 5 a side elevation, and Fig. 6 a cross section
showing, to a larger scale, the construction of the outside fire bars.
Figs. 7 and 8 are perspective views showing the manner in which the said hollow
fire bars are rocked.
a are the fire bars having a main passage a¹ from end to end. bare the lateral
air inlets which are situated in the web or rib of the bar and lead into this main
passage. c are the teeth or projections which, as shown, are arranged to alternate
on opposite sides of the bar. They are approximately of the same width as the

page_text: bar, and those of one bar mesh into those of the next, as shown. dare the openings
with which the teeth are, by preference, provided, and through which the air
passes.
The arrangement of the air inlets and the teeth and openings will be readily seen
by reference to the views of the outer bar shown in Figs. 4, 5, and 6, it being
understood that there is a corresponding set of teeth and openings on each side of
the intermediate bars.
The projections a* shown in these figures are those usually employed on the
outside bars of a rocking grate.
When the bars are arranged in the furnace to form the grate, a clearance of, say,
a inch, or thereabouts, according to the character of the fuel which is to. be
burned in the furnace, is left between the bars.
At the front and rear ends of the bars are pivot pins e which rest in recesses fin
bearer bars, and these pivot pins may be tubular to allow the passage of air into
and out of the hollow bar.
.
In the furnace shown, two sets of bars are fitted end to end, and are socketed
together, as shown at g Fig. 1; being further secured by side pieces h. The joints
are supported by a central bearer bar h¹ permitting them to rock freely.
...i is a connecting rod which extends along the front of the furnace, and k are the
pins on the bars which project into holes in the said rod. These pins are secured
at the lower part of the depending mouths a' of the bars. is the lever whereby
the connecting rod i may be reciprocated to rock the fire bars. This lever is
slotted to engage a pin i on, the connecting rod, and its fulcrum is carried in a
bracket m, arranged in any convenient position under the dead plate and secured
thereto, or to the bearer barf, by nuts or otherwise. It will be seen that the
depending mouth serves, as it were, as a crank or rocking arm, and converts the
movement of the connecting rod into rocking movements of the bars.. The lever l
is operated by a loose or removable handle which is fitted onto a square on its
fulcrum, when it is desired to rock the grate, and is removed when the rocking
operation is completed. When the said lever is in its central position, the grate
surface is perfectly level and even, whereas, when the lever is moved, either to its
extreme left, or right, position, the bars are rocked as indicated respectively in
Figs. 7 and 8. By this arrangement of rocking mechanism, the pawls and ratchets,
and other devices, which are now usually employed to rock fire bars, are dispensed
with, and the same results obtained without them.
The enlarged depending mouth a' at the front of the bar, allows the bearer
bar to be made strong enough to properly support the grate, without lessening
the draught through the bar, and the connecting rod i is connected directly to the
fire bar instead of to a lever, or the like, as is usual in rocking grates.
n is the opening in the fire bridge N in which the rear end of the bar is
supported upon the bearer bar f', or otherwise. This opening extends through
the fire bridge in line with the bars and enables the air drawn along the bars from
the hollow teeth or projections, and the lateral air inlets, to pass out behind the
bridge, where it mixes with the flame and gases from the fire, so ensuring complete
combustion.
p is the damper at the back of the bars, by which the draught from the
passage a' is regulated. It extends the full width of the furnace, and is operated
by a rod g (provided with a handle q¹) arranged preferably immediately under the
bars at one side of the furnace and carried in the front bearer bar frame (see
Fig. 1).
is the guard, which is of wedge or triangular shape, and is secured to the back
of the bridge. It serves to prevent dust, and other matters, from the fire, or
flue, falling over the bridge upon the damper p and finding their way into the
fire bars.
Instead of the arrangement of pins k on the bars, and connecting rod i, above
described, the pins might be formed on the connecting rod and engage in holes in
the bar

page_text: The improvements herein described are applicable to marine, locomotive,
portable engine, and other furnaces, and permit of all clinkers and refuse
material from the fire being broken up by crushing them between the teeth of
-the bars.
Having now particularly described and ascertained the nature of my invention,
and in what manner the same is to be performed, I declare that I claim:
1. A rocking furnace grate, having hollow bars formed with lateral air inlets,
in their web or rib and with teeth or projections (preferably hollow and serving
as air inlets) these bars having depending mouths and serving to discharge heated
air through and behind the fire bridge where it meets and mingles with the products
of combustion from the fuel, substantially as described.
2. In a rocking furnace grate of the kind specified, the means or arrangement
for supporting and rocking the bars, comprising the solid or tubular pivot pins on
the said bars, resting upon transverse bearer bars, the pins on the downwardly
depending mouths, the connecting rod engaging these latter pins, and the slotted
lever adapted to receive a removable handle for operating the connecting rod and
so rocking the bars, substantially as described.
3. In a rocking furnace grate, the combination with the hollow fire bars having
lateral air inlets and teeth (preferably hollow), of a fire bridge having an opening
through which the hot air from said bars can pass, a dust guard arranged at the
rear of such bridge above the opening, and a damper also at the rear of the bridge,
substantially as described.
4. The improved construction of hollow rocking fire bars, substantially as
described.
5. My improvements in furnaces and in rocking fire bars therefor, substantially
as hereinbefore described with reference to the accompanying drawings.
Deted this 16th day of March 1907
ERNEST DE PASS,
Chartered Patent Agent,
78, Fleet Street, London, and 5 Market Street, Nottingham,
Agent for the Applicant.

page_text: f'
Fig. 3.