IMPROVEMENTS ON FURNACES FOR STEAM BOILERS
Year: 1878

page_text: LETTERS PATENT to Lionel Varicas, of 24, Chancery Lane, in the County of
Middlesex, Patent Agent, for the Invention of "IMPROVEMENTS ON FURNACES
FOR STEAM BOILERS." A communication from abroad by William Mack
Fisher, of Cincinnati, in the County of Hamilton, and State of Ohio, United
States of America
Sealed the 14th February 1879, and dated the 9th October 1878.
COMPLETE SPECIFICATION filed by the said Lionel Varicas at the Office of
the Commissioners of Patents on the 9th October 1878.
LIONEL VARICAS, of No. 24, Chancery Lane, in the County of Middlesex, Patent
Agent. "IMPROVEMENTS ON FURNACES FOR STEAM BOILERS." A communication
from abroad by William Mack Fisher, of Cincinnati, County of Hamilton, and State
of Ohio, United States of America.
This Invention relates to furnaces for steam boilers where a secondary grate is
used directly in rear of the ordinary primary grate for supporting a bed of incan-
descent coals periodically supplied from the rear end of the primary grate, for the
purpose of igniting the gases passing over from the primary grate in the form of
smoke.
My improvement consists in arranging the secondary grate at right angles or
thereabouts to the primary grate, and supplying it with currents of fresh air
entering at the side of the furnace in the direction of the grate bars of such
secondary grate, by reason of which construction the sheets of flame arising from
such secondary grate stand across the current of gases from the primary grate, and
by retarding them cause their more perfect combustion before they enter the flues
of the boiler..
The annexed Drawing illustrates my Invention; Figure being a perspective
view, and Figure 2 a longitudinal section thereof.
The steam boiler shewn is provided with the usual grate "G" at one end, which I
call the primary grate, on to which the fuel is fed through a door by hand, or in

page_text: any other preferred manner. Immediately in the rear of this primary grate I
arrange a secondary grate "A," on to which burning coals are fed from the rear end
of the primary grate. The fuel on secondary grate "A" is continually kept in a
bright incandescent state, so that the gases passing over it from the grate "G" will
be ignited, and pass in the form of flame to and through the flues of the boiler. To
this end the secondary grate "A" receives fresh air from a separate air chamber
under it to supply the necessary oxygen, said separate air chamber being formed by
dividing the ash-pit under the grates by a partition wall along their junction.
Access to the secondary grate and to the air chamber under it can be had through
suitable doors in the side of the furnace setting or brickwork.
The grate bars of the secondary grate are arranged at right angles or thereabouts
to the grate bars of the primary grate and to the flue back of the grates, so that the
sheets of flame of the secondary grate, by running across the current of gases from
the primary grate, tend to retard them sufficiently to give time for their ignition
before they pass into the flues.
The partition wall under the grates extends down to the bottom of the ash-pit, so
that all air for the secondary grate enters its separate ash-pit or air chamber from
the side of the furnace in the direction of its grate bars.
The bridge wall "B". is arranged directly in rear of the secondary grate.
What I claim and desire to secure by Letters Patent is, the combination, substan-
tially as specified, of the primary longitudinal grate, the secondary transverse grate,
the solid transverse partition at the junction of the grates, dividing the ash-pit down
to the bottom so as to form a separate transverse air chamber for supplying the
.transverse grate with fresh air from the side of the furnace.
In witness whereof, I, the said Lionel Varicas, have hereunto set my hand
and seal, this Ninth 'day of October, in the year of our Lord One thousand
eight hundred and seventy-eight.
LIONEL VARICAS. (L.S.)