IMPROVEMENTS IN FURNACES
Year: 1876

page_text: LETTERS PATENT to George Butler, of Southwark, in the County of Surrey,
Engineer, for the Invention of "IMPROVEMENTS IN FURNACES."
202
PROVISIONAL SPECIFICATION left by the said George Butler at the Office
of the Commissioners of Patents on the 6th October 1876.
GEORGE BUTLER, of Southwark, in the County of Surrey, Engineer.
MENTS IN FURNACES."
" IMPROVE-
My Invention relates to furnaces having movable fire-bars, and consists of an
improved arrangement of parts whereby the alternate bars are caused respectively
to move upwards and downwards, whilst at the same time the whole series of bars
receives a horizontal to-and-fro motion.
In carrying out my Invention I construct the bars with two recesses at each end,
and I support them upon cross bearers consisting of bars of a trough shape which
are mounted upon knife edge pivots in the sides of the flue. The two upper
extremities of the sides of each trough correspond to the recesses in the bars and
form pivots for the same, but the fire-bar only rests upon one of each pair of pivots
at a time; for example, representing the four pivots by the numbers 1, 2, 3, and 4,
if one bar rests upon pivots 1 and 3 the neighbouring bar on each side will rest
upon pivots 2 and 4, and when the bearers are moved by a lever or otherwise the
one bar descends until it rests also upon pivots 2 and 4, whereby its motion is
arrested and the neighbouring bar on each side ascends, all the bars at the same
time moved longitudinally; during the back motion of the bars the action is
reversed, the bars which were elevated being depressed, and vice versa. By means
of this arrangement the clinkers are more effectually broken up, whilst by reason
of the state of equilibrium of the bars the power necessary to work them is reduced
to a minimum.
The bars are, by preference, so arranged that they may be all cast from one
pattern, the adaptation to the bearers requisite for the motions before-mentioned
being obtained by reversing the alternate bars longitudinally in placing them in
position.

page_text: When it is required to construct the bars in two or more lengths an additional
bearer or bearers may be employed, in which case the latter may consist of single
or double pivots according to circumstances.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by the
said George Butler in the Grent Seal Patent Office on the 6th April 1877.
GEORGE BUTLER, of Southwark, in the County of Surrey, Engineer. " IMPROVE-
MENTS IN FURNACES."
My said Invention relates to furnaces having moveable fire-bars, and consists of
an improved arrangement of parts whereby the alternate bars are caused respectively
to move upwards and downwards, whilst at the same time the whole series of bars
receives a horizontal to-and-fro motion.
In order that my said Invention may be perfectly understood I shall now proceed
more particularly to describe the same, and for that purpose shall refer to the several
Figures on the annexed Sheet of Drawings, which illustrate the application of my
Invention to a furnace flue adapted for a Cornish boiler.
Figures 1 and 3 of the accompanying Drawings represent respectively longitudinal
sections of the furnace flue with the bars shewn in two different positions; and
Figures 2 and 4 are corresponding transverse sections of the same; Figure 5
represents a side elevation of one of the bars detached.
A, A¹, are the bars which I construct with four recesses a, a, b, b, (two at each
end, as shewn clearly in Figure 5) and support upon cross bearers B, B', consisting
of bars of a trough shape which are mounted upon knife edge pivots C, C, in the
sides of the flue D. The two upper extremities of the sides of each trough corre-
spond to the recesses in the bars and form pivots for the same, as shewn at 1, 2, 3,
and 4, but the fire-bar in its normal position only rests upon one of each pair of
pivots at a time; for example, if one bar rests upon pivots 1 and 3 the neighbouring
bar on each side will rest upon pivots 2 and 4, and when the bearers B, B', are
moved by the lever E or otherwise in one direction, the one bar descends until it
rests also upon pivots 2 and 4, whereby its motion is arrested and the neighbouring
bar on each side ascends, all the bars at the same time being moved longitudinally.
In Figures 1 and 2, in which the bars are represented in their normal level position,
the bars A are shewn as resting upon pivots 1 and 3 whilst the bars A¹ rest upon
pivots 2 and 4. By moving, however, the bearers B, B¹, by the aid of the lever E,
or otherwise, in the direction indicated by the arrow in Figure 1, the bars A will
be caused to descend until they also rest upon pivots 2 and 4 whereby their motion
is arrested, and the bars A¹ will ascend both sets of bars A, A³, at the same time
moving longitudinally in the direction of the arrow, Figure 1; Figures 3 and 4
represent the latter portion of the bars.
When the bearers B, B¹, are moved in the opposite direction to that indicated by
the arrow the action is reversed, the two sets of bars (A, A¹,) are moved back
Jongitudinally until they come into contact with the fire-bridge F, and the bars A
are elevated whilst the bars A¹ are depressed.
By causing the alternate bars to move respectively upwards and downwards, in
the manner herein-before described, when a reciprocating to-and-fro motion is
imparted to the two series of bars simultaneously (which operation may be per-
formed at intervals), the clinkers are more effectually broken up whilst at the same
time, by reason of the two sets of bars being in a condition of equilibrium, the
power necessary to work them is reduced to a minimum.
The bars are by preference arranged, as shewn in the example illustrated, so
that they may be all cast from one pattern, the adaptation to the bearers requisite
for the motions, herein-before described, being obtained by reversing the alternate.
bars longitudinally in placing them in position, the recesses a, it, and b, b, of the

page_text: bars A corresponding respectively to the bearers B and B¹, whilst the recesses a, a,
and b, b, of the bars A¹ correspond respectively to the bearers B' and B.
When it is required to construct the bars in two or more lengths an additional
bearer or bearers may be employed, in which case the latter may consist of single
or double pivots, according to circumstances.
Having now described and particularly ascertained the nature of my said Invention,
and the manner in which the same is or may be used or carried into effect, I
would observe in conclusion that 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, the peculiar combination of furnace bars and bearers constructed,
arranged, and operating substantially in the manner and for the purposes herein-
before described and as illustrated by the accompanying Drawings.
In witness whereof, I, the said George Butler, have to this my Specification,
set my hand and seal, this Sixth day of April, One thousand eight hundred
and seventy-seven.