A NEW OR IMPROVED APPARATUS FOR FEEDING FUEL TO FURNACES AND FIRE-PLACES
Year: 1878

page_text: LETTERS PATENT to James McMillan, of Glasgow, in the County of Lanark,
North Britain, for the Invention of "A NEW OR IMPROVED APPARATUS FOR
FEEDING FUEL TO FURNACES AND FIRE-PLACES."
Sealed the 25th March 1879, and dated the 8th October 1878.
PROVISIONAL SPECIFICATION left by the said James McMillan at the Office
of the Commissioners of Patents on the 8th October 1878.
"A
JAMES MCMILLAN, of Glasgow, in the County of Lanark, North Britain.
NEW OR IMPROVED APPARATUS FOR FEEDING FUEL TO FURNACES AND FIRE-
PLACES.
37
This Invention relates to new or improved apparatus for feeding fuel to furnaces
or fire-places either intermittently or constantly, and it consists under one form as
follows:-
The bottom of the furnace or fire-place is formed with a hollow or opening
through the fire-bars. Below the fire-bars is a moveable chamber carried on rollers
or rails, so that the said chamber can be moved horizontally backwards and forwards
beneath the bars. This chamber has a dead plate or ribs or bars projecting hori-
zontally from its hinder end. Thus when the chamber is drawn outwards for
being charged the said dead plate or ribs or bars passes or pass under the opening
in the fire-bars, and closes or close it so as to prevent the fuel from falling down
therethrough. When the chamber is charged with fuel it is pushed back under-
neath the opening, and the green fuel is forced upwards therefrom into and below
the burning fuel by the rising of a plate, which forms the moveable bottom of the
chamber. This rising of the botton and the lowering thereof also is effected by
its being fitted with and carried upon a series of crossed and linked levers, which
as the lower levers of the set are moved horizontally inwards or outwards rise or
fall rapidly, and therefore correspondingly raise or lower the moveable bottom.
The movement of the lower bars is effected by a screw or the equivalent thereof.
DI

page_text: Under a second form, and which is more especially adapted for continuous firing,
the opening through the fire-bars has attached to it a curved pipe projecting out
towards the front of the furnace. In the front part of the pipe a screw feeder or
an equivalent continuous feeder is attached, so that as the screw or equivalent
feeder is rotated or otherwise actuated either by a steam engine or other mechanical
notor or by the hand of an attendant, the fuel which is contained in a hopper is
continuously fed up through the opening in the fire-bars on to the grate and
underneath the burning fuel. This apparatus may also be used for intermittent as
well as for continuous feeding. As an intermittent fuel feeder the outer part or
end of the feeding tube may be formed with a chamber of any specific size, so as
to contain a measured quantity of fuel. In this chamber is a piston or the equiva-
lent thereof, which can be moved backwards and forwards in the chamber either by
a lever, screw, or by a rack and pinion movement, so that the chamber being
charged with fuel this is discharged into the. furnace or fire-place by the forcing of
the piston forwards.
The apparatus herein-before described may be provided with a counter or
indicator, shewing the rate at which it has been driven, or in other words, the
quantity of fuel supplied to a furnace or fire-place in any given time. It is also
preferred that the discharge tube be formed with a taper or gradual enlargement
towards the point of discharge.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said James McMillan in the Great Seal Patent Office on the 8th April
1879.
JAMES MOMILLAN, of Glasgow, in the County of Lanark, North Britain. "A
NEW OR IMPROVED APPARATUS FOR FEEDING FUEL TO FURNACES AND FIRE-
PLACES."
My said Invention relates to new or improved apparatus for feeding fuel to
furnaces or fire-places from underneath, so that the smoke and gases from the green
fuel are consumed by the live fuel above.
And in order that my said Invention may be properly understood I now proceed
more particularly to set forth the system, mode, or manner in or under which the
same is or may be used or practically carried into effect, reference being had to the
accompanying Drawings, and to the letters and figures marked thereon, that is to
say :-
Figure 1 is a front elevation, Figure 2 a longitudinal vertical section, and Figure 3
a sectional plan of a Cornish boiler, to the furnace of which is applied apparatus
constructed according to my Invention. The bottom of the furnace A is formed
with a hollow or opening a through the fire-bars, and situated preferably at about
the middle of the furnace bottom. Below the fire-bars in the ash-pit of the furnace
are rails b, b, mounted in brackets, or otherwise supported along the ash-pit on
either side thereof, and mounted upon wheels c, c; running upon those rails is a
chamber or box-like receptacle C (shewn separately in longitudinal section in
Figure 4). This receptacle C has projecting horizontally from its hinder end a
dead plate, or a series of bars or ribs c', which when the receptacle C is drawn
outwards for being charged pass or passes under the opening a and support the
fuel. When bars are used they may be attached to their framing by bolts passing
through slotted holes, which will allow the longitudinal movement of the bars in
contracting or expanding.
When the receptacle C is filled with fuel it is pushed back until it is immediately
under the opening a, and the said fuel is forced upwards therefrom into the fire-
place below the live fuel by the raising of a plate c³, which forms a moveable
bottom of the receptacle C. This raising of the bottom may be effected by any
suitable or convenient arrangement of screws, cams, levers, or excentrics. In the
Drawings (Figure 4) I have shewn a method of effecting the said raising by means
of a system of crossed and linked levers d, d, one set on either side of the
receptacle C. The moveable bottom rests upon the upper ends of each of these
sets of levers, and the lower ends of the bottom levers are connected, those at back
(on both sides) to the arms f of a collar f¹, and those at front to the arms' f of a
similar collar to that f¹. Upon a squared rod g or a piece to which this rod is
attached, so that it turns therewith, are formed screws g¹, the one right handed
and the other left handed, and upon these screws run the collars f'. By partly
rotating this rod g the collars f¹ run upon the screws g¹ (to a distance which can
be regulated by adjustable stops between the collars f'), and their ends being
brought towards each other the levers take the position illustrated in dotted lines
in Figure 4, and the bottom of the receptacle is moved up to the top of the said
receptacle, and the green fuel therefrom fed underneath the fire in the grate or
furnace. The receptacle C may now be run outward into the position, Figure 3,
in readiness to receive a fresh charge, the dead plate or series of bars c² covering
the opening a and retaining the fuel in place. The rod g is square, and when the
receptacle C is moved backwards or forwards runs through a squared hole in the
hand wheel g³, so that it can receive its rotatory motion from the said wheel to
raise the bottom c. The furnace bars which I prefer to use are those to which a
rotatory motion can be given from the outside of the furnace, so as to break up
clinkers. In Figure 5 I have shown in longitudinal vertical section a portion of a

page_text: still and its furnace with which is combined apparatus similar in all essential
respects to that herein-before described, but as it is of larger size the appliances for
operating it are different. Parts of this apparatus which correspond to those
described with regard to the apparatus illustrated in Figures 1 to 4 are marked
with the same letters of reference, and require no further description. The rod g
is mounted in bearings, so as to be capable of rotation therein; the screws g' are
upon a collar having a square hole through it, so that it. can slide upon the rod g,
which is also square at the part over which this collar slides. The receptacle C can
thus be drawn forward without the rod g projecting in front, as the collar of the
screws will run upon the said rod. The rod g has upon it a toothed wheel h, by
which it may be rotated through the pinion i upon the shaft I turned by a hand
wheel or handle, as at i', or by other motive power. The receptacle C is driven
backward or forward by means of a chain C2 passing over sprocket wheels c³, c³,
receiving the necessary inotion by means of a bevel pinion also upon the shaft I,
the said pinion communicating motion to the shaft J, upon which the sprocket
wheel is carried by gearing with the bevel toothed wheel j upon the said shaft J.
The pinions i and may be formed in one, as shown, and may be attached to the
shaft I by a groove and feather arrangement, so that the said pinions may
be slidden along the said shaft to simultaneously engage the pinion i with
the wheel h, and disengage the pinion from the wheel j, so that by operating the
handle the bottom of receptacle C may be raised or lowered. By sliding the
pinions in the other direction the pinion and wheel h are disengaged, and the
pinion and wheel j are engaged, and by now operating the handle & the receptacle
C is drawn forward or backward by the chain C. The aforesaid mechanism is
shewn separately in plan in Figure 6. In confined places where the rod g is close
to the floor a ratchet lever may be employed to turn it for raising the bottom of the
receptacle C.
The
Figure 7 represents in sectional clevation an ordinary fire-grate shewing the
application thereto of apparatus constructed according to my Invention.
bottom of the grate is open, and sliding underneath is the receptacle C provided
with a dead plate c', and with means for raising the bottom, which may be
similar to those herein-before described. The receptacle C may support an ash pan,
as at K. The apparatus is essentially similar in its construction and action to
those herein-before described, and similar parts are marked with the same letters
of reference.
Under a second form the opening through the fire-bars has attached to it a pipe
projecting out towards the front of the furnace, as illustrated in section in Figure 8,
where but a portion of the fire-bars of the furnace are shewn, the opening there-
through being marked a, and the pipe being marked L. The said pipe is straight
at its fore part, but curves upwards (and by preference gradually enlarging, as
shewn) at its other end, which communicates with the opening a.
The straight
fore part of the tube L constitutes a chamber with an opening at the top, which
may be covered by a close fitting door 7, through which opening the said chamber
is charged with fuel. In the fore part of the pipe L is a piston M, which being
moved forward into the position shewn in dotted lines, after the door Z has been
closed and fastened down, presses the fuel up through the opening a into the
furnace. The piston M. may be operated in any desired manner through lever,
screw, or rack and pinion movements by hand or by power; for instance, its rod
may at its forward end enter a steam or hydraulic cylinder, and have a piston
attached to it, so that by admitting steam or water to one or other side of this!
piston the piston M may be pressed forward or withdrawn.
Figure 9 represents the end of a tube L similar to that shewn in Figure 8, but
provided with arrangements to adapt it for continuous feeding. In the front part of
the pipe a screw feeder or an equivalent continuous feeder is contained, as at N, so
that the said feeder being rotated or actuated by a steam engine or by other suit-
able motor (or by hand in small furnaces or fire-places) the fuel, which is supplied
through an opening p above the feeder N from a hopper P, is continuously fed up

page_text: through the opening (a) in the fire-bars to the grate, and underneath the burning
fuel thereon. It is preferred to have a considerable column or weight of coal in
the hopper P to prevent the screw from raising the contents of the hopper.
Having now described and particularly ascertained the nature of my said
Invention, and the system, mode, or manner in or under which the same is or may
be used or practically carried into effect, I would observe in conclusion that I wish
it to be understood that I do not limit myself to the precise constructions and
modes of operating the apparatus constituting my said Invention, as it will be
understood that they may be varied without departing from the nature of my
said Invention. I also wish it to be understood that in the following claiming
clauses I make no distinct claim to the feeding green fuel to underneath the live
fuel, but what I consider to be novel and original, and therefore claim as the
Invention secured to me by the herein-before in part recited Letters Patent is,―
First. The apparatus herein-before described, and illustrated in the accompanying
Drawings, for feeding fuel to furnaces and fire-places, that is to say, an apparatus
consisting of a receptacle underneath the fire-bars, from which receptacle the green
fuel is urged upwards through an opening in the furnace or fire-place bottom, and
underneath the live fuel in the said furnaces, essentially as herein-before described.
Second. The arrangement of the apparatus essentially as described with reference
to Figures 1 to 4 of the accompanying Drawings.
Third. The arrangement of the apparatus essentially as described with reference
to Figures 5 and 6 of the accompanying Drawings.
Fourth. The arrangement of the apparatus for ordinary fire-grates, essentially as
described with reference to Figure 7 of the accompanying Drawings.
Fifth. The arrangement of the apparatus described with reference to Figure 8,
and also the modification for continuous feeding, described with reference to Figure 9
of the accompanying Drawings.
In witness whereof, I, the said James McMillan, have hereunto set my
hand and seal, this Seventh day of April, in the year of our Lord One
thousand eight hundred and seventy-uine.
TAMS MOTTAT
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TAMOT AXT