IMPROVEMENTS IN FURNACE BARS
Year: 1876

page_text: LETTERS PATENT to William Wright, of Sheffield, in the County of York,
Commercial Traveller, for the Invention of "IMPROVEMENTS IN FURNACE
BARS."
Sealed the 26th May 1877, and dated the 23rd December 1876.
PROVISIONAL SPECIFICATION left by the said William Wright at the Office
of the Commissioners of Patents on the 23rd December 1876.
WILLIAM WRIGHT, of Sheffield, in the County of York, Commercial Traveller.
" IMPROVEMENTS IN FURNACE BARS."
This Invention relates to curved furnace bars, and has for its object to produce
larger air or draught space, thereby causing more perfect combustion and a much
lighter and consequently a cheaper bar. I attain the said object thus:-I form the
bars of metal to any suitable curve or curves; the projecting or convex curves and
the concave or return curves may be either of the same or a dissimilar character;
the concave curves I prefer to make somewhat larger than the convex ones. When
both the said curves are circular, or thereabouts, I form the perforations or draught
spaces through the bars, somewhat like a horse shoe in shape, so as to maintain an equal
thickness or thereabouts of metal between such perforations and the curved exterior
of the bar. If the said curves are oval, or of any other shape, the form of the perforations
or draught spaces are made to suit such external curves, and so as to maintain an
equal or nearly equal thickness of metal between such draught spaces and the
exterior of the bar, as in the previous case; by this method I produce a bar with
more air or draught space and less weight of metal, consequently a cheaper bar.
One end of my improved bar is gradually reduced underneath, to prevent the bar
from warping or bending sideways, a common fault in the curved furnace bars now
used.
"
The said curves or projections reduce the friction of the bar upon the dead plate
whilst expanding and contracting.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Wright in the Great Seal Patent Office on the 20th June
1877.
WILLIAM WRIGHT, of Sheffield, in the County of York, Commercial Traveller.
"IMPROVEMENTS IN FURNACE BARS."
This Invention relates to curved furnace bars, and has for its object to produce
larger air or draught space, thereby causing a more perfect combustion of fuel, and
a much lighter and consequently cheaper bar, which object I attain thus,—
In order that my said Invention may be more clearly and more fully understood,
and be more readily performed, I will explain the same with the aid of the accom-
panying Drawing, which forms part of this Specification, reference being mado
thereto by the numerals and letters marked thereon, and which reference applies to
each Figure of the said Drawing, where the same index numerals and letters appear.
Figure 1 is a plan view of a set of my improved bars as fixed in a furnace.
Figure 2 is a side elevation of one of such bars.
Figure 2 is a plan view of the under side of the said bar, looking upwards,
shewing the curved rib.
Figure 3 is a plan view of a bar, having its sides so shaped as to form a straight or
nearly straight single bar; Figure 3* is a side elevation of the same.
I form the said of metal, generally cast iron, to any suitable curve or curves;
the projecting or convex curves a and the concave or return curves b may either be
of the same or of a dissimilar character. The concave curves are made larger than
the convox ones, to allow of the air or draught space c between them.
When both the said curves are circular, as shewn, or thereabouts, I form the
perforations or draught spaces c' through the bars, somewhat like a horse shoe in
shape, so as to maintain an equal thickness, or thereabouts, of metal at e, between
such spaces c¹ and the curved exterior of the bar, sec Figures 1, 2, and 3.
If the curves a, b, are made oval or other shaped, the form of the perforations or
draught spaces c' is adapted to such external curves, and so as to maintain an equal
or nearly equal thickness of metal at e, between such draught spaces and the exterior
of the bar, as in the previous case; by this method I produce a bar with more air
or draught space and less weight of metal, and consequently a cheaper and a more
durable bar.
When desired I propose to construct the furnace bottom of a series of straight or
nearly straight edged bars, similar to those shewn in Figures 3 and 3*.
Having thus fully described and ascertained the nature of my said Invention, and
the method of performing the same, I wish it to be understood that I do not restrict
myself to the precise dimensions or shapes of the details now illustrated, but I
claim as my Invention and desire to secure by the before-mentioned in part recited
Letters Patent, the formation of furnace bars with curved perforations, securing
thereby a greater air or draught space, and a more equable distribution of the metal
constituting such bars than in any bars for a similar purpose hitherto produced,
substantially as herein described and shewn in the Drawing.
In witness whereof, I, the said William Wright, have hereunto set my hand
and seal, this Nineteenth day of June, in the year of our Lord One thousand
eight hundred and wowander