IMPROVEMENTS IN AND RELATING TO APPARATUS FOR SUPPLYING FUEL TO FURNACES
Year: 1879

page_text: L
LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention
of "IMPROVEMENTS IN AND RELATING TO APPARATUS FOR SUPPLYING FUEL TO
FURNACES." A communication from abroad by D. M. Thomas, of Detroit,
Michigan. United States of America.
PROVISIONAL SPECIFICATION left by the said William Robert Lake at the
Office of the Commissioners of Patents on the 12th February 1879.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN AND RELATING TO APPA-
RATUS FOR SUPPLYING FUEL TO FURNACES." [A communication from abroad by
D. M. Thomas, of Detroit, Michigan, United States of America.]
This Invention relates to improvements in devices for mechanically feeding fuel
to boiler-furnaces in regulated quantities and at desired intervals of time for the
purpose of keeping up a uniform fire under the boilers. As ordinarily fed through
furnace doors opened for the purpose, so much cold air is usually admitted that
when the coals are thrown in, a large quantity of smoke is instantly made, which
passes off unconsumed through the flue-passages, and the coals thus fed and in the
usual way spread over the surface of the fire upon the grates, interpose between the
incandescent fuel and the boiler a cold surface, the tendency being to deaden the
fire and consequently lower the pressure of steam. My object is to avoid these
difficulties in the way of keeping up a steady fire and uniform pressure of steam.
The said Invention consists in the construction of devices for measuring the fuel
any. desired quantities, in the construction of mechanical devices for feeding the
fuel to the furnace; in the combination of said measuring and feeding devices; in
the peculiar construction and operation of the grate-bars; in the combination of
said grate-bars with the measuring and feeding devices; in the combination of an
independent dumping grate or plate with a boiler-furnace; in the combination of
said independent dumping grate with the grate-bars of a boiler-furnace, which bars
are so arranged as to force in their reciprocating movement the debris of the fire on
to said dumping grate; in a boiler-furnace the combination of a mechanically
measuring feeding device. with carrying and shaking bars; and in combination with :
in
Price Bid1

page_text: a boiler furnace provided with a mechanically measuring and fuel-feeding device,
and with grate-bars operated thereby, an independent dumping grate.
In carrying the said Invention into practice I provide a series of grate-bars set
upon an inclination from front to rear; the front ends of these bars terininate in a
hook, by means of which and their connection they have a short reciprocating
movement; both ends of these bars have bearing surfaces, each of which are sup-
ported upon suitable bearings on bars extending across the furnaces; these bearing
surfaces project on each side of the bars to form shoulders to keep the bars apart to
allow spaces for the upward.admission of air and the ashes to fall through into the
ash-pit. There is another series of bars set upon the same angle and resting upon
the saine supports, and they are alternated with the first named bars, and are
susceptible-of-no-reciprocating movement; all these bars are made in a series of
-steps-for-the-purposes-hereinafter described.. Coal being placed upon the upper
step, and the first named bars being given a forward motion, the coal is carried to
the next step-below, where-the-retraction-of-the-bar-leaves-it,-and-the-first step..is.
cleared ready for another supply. As this reciprocating movement takes place at
periodic intervals the coal is advanced downward one step at a time in an incan-
descent condition, the ashes are shaken out, and when the fuel reaches the last and
lowest step the next forward motion of the first named bars will force the debris
onto a supplemental and independently acting grate-plate, the bearing ends of
which bars pass under said plate, so that it acts as a stationary shovel to remove
such debris. This plate is supported upon a shaft which projects through the side
wall of the furnace, and this shaft is provided with a crank by means of which the
shaft is turned or tilted to throw off the debris from the plate into the ash-pit. If
preferred the upper surfaces of these grate-bars may be plain or corrugated, and set.
upon an inclination downward from front to rear, and diagonally across the furnace,
when each alternate bar being forced forward and withdrawn will force the fuel
towards the rear of the furnace, or another construction may be employed to accom-
plish the desired result without departing from the spirit of the said Invention,
which is gradually to force the fuel from front to rear of the furnace, substantially
as described. Neither is it necessary that the first named bars should slide under
the dumping grate, as the same result will be obtained if said plate is supported
below the ends of the bars.
"
A hopper is provided to contain a supply of coal, which latter is supported in a
column upon a table which is placed so as to discharge immediately upon the upper
ends of the first named grate-bars. There are four plates which form a slide or
strike which on a forward motion being given to it will pass under the discharge
end of the said hopper and over the face of the said table, and force as much of the
fuel as is resting thereon, and below the said discharge end of the hopper, on to the
upper end or step of the grate-bars; when withdrawn this slide or strike closes a
well or recess which will be filled with coals from the hopper, to be in like manner
fed on to the grate-bars. This slide may be made adjustable, so that the quantity
of coal at each motion and discharge may be regulated as desired. Reciprocating
motion is given to this frame and slide by a crank-pitman on a shaft, which latter
is supported in suitable bearings; the upper end of this pitman is pivoted to a
frame, or to plates secured thereto; the other arm is provided with a small wheel
or wrist-pin, which travels in a cone-shaped chamber upon the face of a ratchet
wheel. This wheel sleeved upon a shaft is provided around its periphery with a
series of ratchet-teeth, and is actuated by a pawl pivotted to a slotted lever, one
end of which is attached to the last named shaft, while to its opposite and free end
is attached a chain which may be attached to any motive power, so that said lever
may be raised and lowered at regular intervals of time; this chain is attached to
an adjusting bolt working in a slit in the lever, so as to adjust the length of its
stroke, the shorter the stroke the more rapidly will it rotate the wheel, and through
the connections herein before named the oftener will the fuel supply be replenished
to the grates; the longer its stroke the longer will the wheel be in completing a
revolution, and hence the less often will the fuel be fed. The plate also actuates

page_text: the reciprocating grate-bars by means of a flange engaging with the said hooks upon
the ends of said bars, so that every forward or retrograde motion of said frame is
communicated to said bars as hereiubefore described. The grate-bars project into
the boiler-furnace from the front through an opening therein, and the measuring
and feeding apparatus are so secured and placed that the fuel is fed through such
opening to said bars.
In the front wall of the furnace, immediately above the opening last described,
there is a flue provided with openings to discharge air onto the fuel as soon as it
has been fed on to the bars; this flue communicates with other flues in the sides of
the furnace-walls, which said flues take air from outside said walls; the air thus
taken in is highly heated before it is passed to the furnace, so that it assists in
burning the gases and prevents the throwing off of smoke from the fuel as it is fed
into the furnace.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Robert Lake in the Great Seal Patent Office on the 12th
August 1879.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN AND RELATING TO APPA-
RATUS-FOR-SUPPLYING-FUEL-TO-FURNACES." A-communication-from-abroad-by-
D. M. Thomas, of Detroit, Michigan, United States of America.
This Invention relates to new and useful improvements in devices for mechani-
cally feeding fuel to boiler-furnaces in regulated quantities and at desired intervals
of time, for the purpose of keeping up a uniform fire under the boilers. As fuel is
ordinarily fed_through_furnace.doors.opened_for_the_purpose_so_much_cold_air_is_
usually admitted, that when the coals are thrown in a large quantity of smoke is
instantly made, and passes off unconsumed through the flue passages, and the coals.
-thus fed, and in the usual way spread over the surface of-the fire upon the grates,
interpose between the incandescent fuel and the boiler a cold surface, the tendency
being to deaden the fire, and consequently lower the pressure of steam. The object
of this Invention is to avoid these difficulties by keeping up a steady fire and
uniform pressure of steam.
The said Invention consists primarily in the construction of devices for measuring
the fuel in any desired quantities; also in the construction of mechanical devices
for feeding the fuel to the furnace; also in the combination of the said measuring
and feeding devices; also in the peculiar construction and operation of the grate
bars;
also in the combination of the said grate bars with the measuring and feeding
devices; also in the combination of an independent dumping grate or plate with
a boiler-furnace ; also in the combination of the said independent dumping grate
with the grate-bars of a boiler furnace, the said bars being so arranged as to force
in their reciprocating movement the débris of the fire upon said dumping grate ;
also in the combination in a boiler-furnace of mechanically measuring feeding devices
with carrying and shaking bars; also in the combination with a boiler-furnace
provided with a mechanically measuring and fuel feeding device, and with grate
bars operated thereby, of an independent dumping grate, and in the combination
with the said furnace of a peculiarly arranged flue, as hereinafter described.
Figure 1 is a perspective view of a boiler-furnace, taken from near the front
thereof, showing the various devices attached, and a portion of the side wall removed
to more clearly explain the operation of the said devices.
Figure 2 is a side elevation of the mechanically moving parts detached from the
furnace.
Figure 3 is a front view, partly in section, of portions of the same detached.
Figure 4 is a plan of a pair of the grate bars and adjacent parts.
Like letters indicate the same parts throughout the Drawing.
-AA-represent-a-series-of-grate-bars-set-with-an inclination.from-front-to-rear
as shown; the front ends of these bars terminate in a hook a, by means of which
and their connection they have a short reciprocating movement. Both ends of these
bars have bearing surfaces which are supported upon suitable bearings on bars d
extending across the furnaces. The aforesaid bearing-surfaces project on each side
of the bars to form shoulders to keep the bars apart to allow spaces for the upward
admission of air, and the falling of the ashes through them into the ash-pit; B, B,
indicate another series of bars set at the same angle, and resting upon the same
supports, the said bars being alternated with the bars A, and susceptible of no
reciprocating movement. All of these bars are made in a series of steps as shewn,

page_text: for the purposes hereinafter described. Coal being placed upon the upper step, and
the bars A having a forward motion imparted to them, the coal is carried to the
next step below, where the retraction of the bar leaves it, and the first step is
cleared ready for another supply. As this reciprocating movement takes place at
certain intervals the coal is advanced downward, one step at a time, in an incan-
descent condition, the ashes are shaken out, and when the fuel reaches the last and
lowest step the next forward motions of the bars A will force the debris upon the
supplemental and independently acting grate plate C; one of the bearing ends of
the bars A passes under the said plate, so that it acts as a stationary shovel to
remove sucli débris. The plate is supported upon a shaft d', which projects
through the side wall of the furnace, and is provided with a crank e, by means of
which the said shaft is turned or tilted to throw off the débris from the plate into
the ash-pit. If preferred, the upper surfaces of these grate-bars may be plain or
corrugated, and set upon an inclination downward from front to rear, and diagonally.
across the furnace; each alternate bar being forced forward and withdrawn will
force the fuel toward the rear of the furnace; or any other construction may be
employed which will accomplish the desired result without departing from the
spirit of the said Invention; that is to say, the gradually forcing of the fuel from
front to rear of the furnace, as described. Moreover, it is not necessary that the
bars A should slide under the dumping grate, as the same result will be obtained if
the said plate is supported below the ends of the bars.
D is a hopper to contain a supply of coal, which is supported in a column upon
the table E, so placed as to discharge the coal immediately upon the upper ends of
the grate-bars A; F, F', F2, F³, represent four plates forming a slide or "strike,"
which, on a forward motion being given to it, will pass under the discharge end of
the hopper and over the face of the table E, and force the fuel resting thereon, and
below the said discharge end of the hopper, to and upon the upper end or step of the
grate-bars; when withdrawn this slide or "strike" closes a well or recess which will
be filled with coal from the hopper, to be in like manner fed to the grate bars. This
slide may be made adjustable, so that the quantity of coal at each motion and
discharge may be regulated as desired. Reciprocating motion is given to this frame
and slide by the crank-rod or pitman G on the shaft H, supported in suitable
bearings; the upper end of this pitman is pivoted to the frame F, or to plates h.
secured thereto; another arm I is provided with a small wheel or wrist-pin i, which
travels in the cone-shaped groove or chamber k upon the face of the ratchet
wheel J. This wheel is sleeved upon the shaft K, and is provided upon its
periphery with a series of ratchet teeth as shown; it is actuated by the pawl
pivoted to the slotted lever L, one end of which is attached to the shaft K,. while to
its opposite and free end is attached a chain (not shown), which may derive
motion from any suitable motor, so that said lever may be raised and lowered
at regular intervals. This chain is attached to an adjusting bolt m, working in the
slot n in the lever, so as to adjust the length of its stroke; the shorter the stroke
the more rapidly will it rotate the wheel, and through the connections hereinbefore
named the oftener will the fuel supply to the grates be replenished; the longer its
stroke the longer will the wheel be in completing a revolution, and hence the less
often will the fuel be supplied. The frame F also actuates the reciprocating grate
bars by means of the flange o engaging with the hooks a on the ends of the said
bars, so that every forward or retrograde motion of the frame is communicated to
the said bars as hereinbefore described. The grate bars project into the boiler
furnaces from the front through an opening therein, and the measuring and feeding
apparatus are so secured and placed that the fuel is fed through such opening to the
said bars.
In the front wall of the furnace immediately above the opening last described
there is a flue M provided with openings to discharge air onto the fuel as soon as
it has been fed upon the bars. This flue communicates with other flues (not shown)
in the sides of the furnace-walls, which flues take air from outside the said walls;
the air thus taken in is highly heated before it is passed to the furnace, so that it

page_text: assists in burning the gases, and prevents the throwing-off of smoke from the fuel
as it is fed into the furnace.
Having thus fully described the said Invention as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I claim,
First. The hopper, the table, and the reciprocating slide or "strike" combined
_ for the purpose of intermittently measuring the fuel previous to discharging the
same into a boiler furnace, substantially as described.
-Second. The mechanical devices, consisting of a reciprocating slide, (mechanically
actuated;)-by-means-of-which-the-fuel-is-discharged from the table upon the grate-
-bars-of-a-furnace, through-an-opening on-the front wall thereof, substantially as
specified..
Third. The combination of the mechanically measuring and feeding-devices-with-
a boiler-furnace, substantially as set forth.
Fourth. In a boiler-furnace the grate-bars constructed and operating substantially
as described.
Fifth. In a boiler-furnace the combination of the grate-bars constructed and
operating substantially as described, with mechanically measuring and feeding
devices, substantially as and for the purposes set forth.
Sixth. In combination with a boiler-furnace an independent dumping grate
actuated from the outside of the furnace-wall, substantially as specified.
Seventh. The combination with the grate bars A. of an independent dumping
plate or grate when the said bars are adapted in their reciprocating movements to
force the débris of the fire upon the said dumping plate or grate, substantially as
described.
Eighth. In a boiler-furnace the combination of mechanically actuated fuel
measuring and feeding devices, with grate-bars A adapted to receive the fuel upon
their forward ends, and gradually advance the same toward the rear of the furnace,
substantially as set forth.
Ninth. In a boiler-furnace provided with mechanically operating measuring and
fuel-feeding devices, and with grate-bars actuated by the said measuring and feeding
devices, the combination therewith of an independently actuated dumping plate,
substantially as and for the purposes specified.
Tenth. In combination with a boiler-furnace, provided with mechanical devices
for measuring and feeding fuel to the same through an opening in the front of said
furnace wall, the flue M immediately over said opening for the purpose of delivering
heated air to the fuel as it enters the furnace, substantially as and for the purposes
described.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Twelfth day of August, in the year of our Lord One
thousand eight hundred and seventy-nine.