IMPROVEMENTS IN FURNACES AND FIRE-PLACES FOR INDUSTRIAL AND DOMESTIC PURPOSES
Year: 1880

page_text: LETTERS PATENT to Edwin Powley Alexander, of 14, Southampton Buildings,
in the County of Middlesex, Consulting Engineer and British and Foreign
Patent Agent, for an Invention of "IMPROVEMENTS IN FURNACES AND
FIRE-PLACES FOR INDUSTRIAL AND DOMESTIC PURPOSES." A communication
from abroad by Constantin Nikiphoroff, of Paris, in the Republic of France
Colonel of Artillery.
PROVISIONAL SPECIFICATION left by the said Edwin Powley Alexander at
the Office of the Commissioners of Patents on the 17th December 1880.
EDWIN POWLEY ALEXANDER, of 14, Southampton Buildings, in the County
of Middlesex, Consulting Engineer and British and Foreign Patent Agent.
IMPROVEMENTS IN FURNACES AND FIRE-PLACES FOR INDUSTRIAL AND DOMESTIC
PURPOSES." A communication from abroad by Constantin Nikiphoroff, of Paris,
in the Republic of France, Colonel of Artillery.
46
This Invention relates to an improved construction and arrangement of the
grating or fuel bearing surface of furnaces and fire-place for industrial and domestic
purposes, and consists essentially in substituting for the usual arrangement of fire
bars any convenient number of rectangular or other suitably shaped perforated cast
iron gratings, forming units of the grate area to be produced. These units are laid.
together side by side somewhat after the fashion of tiles, and are supported upon
suitable bars or bearers arranged in such a manner as to admit of free passage of
air to the gratings or units. The said units are each cast with longitudinal and
transverse ribs having in some cases lateral projections cast thereon to form the
fuel supporting surface, openings being left between the several ribs in each unit or
separate grating, thereby affording a ready access of air to all parts of the fuel
resting thereon. Lugs or projections are cast on the surrounding edges of each
unit in order to maintain a free air passage between the units when laid or
arranged together edge to edge, other lugs or projections beneath being provided to
serve as guides in laying the units upon their supports or bearers. The said units
can be readily removed and replaced when. worn by a hooked rod adapted for
engaging with the ribs therein. By the use of these units the grate surface is
maintained at a lower temperature, and therefore is less liable to become burnt or
and by the free access of air afforded to the fuel the most inferior kinds of
fuel may be consumed, and a more perfect combustion with less smoke is ensured.
worn,

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Edwin Powley Alexander in the Great Seal Patent Office on the
16th June 1881.
EDWIN POWLEY ALEXANDER, of 14, Southampton Buildings, in the County
of Middlesex, Consulting Engineer and British and Foreign Patent Agent.
"IMPROVEMENTS IN FURNACES AND FIRE-PLACES FOR INDUSTRIAL AND DOMESTIC
PURPOSES." A communication from abroad by Constantin Nikiphoroff, of Paris,
in the Republic of France, Colonel of Artillery.
The said Invention relates to a peculiar construction and arrangement of grating
or fuel bearing surface, equally applicable to furnaces and to fire-places for
industrial and domestic uses, and consists in the substitution for ordinary fire bars,
whether rectilinear, curved, hollow, cylindrical, or of any other shape, of certain
peculiarly constructed square, rectangular, or other suitably shaped gratings or
surfaces, forming either the entire surface or constituting units or parts, as the case
may be, of the grate area, such gratings or surfaces being made with convenient
openings formed by strengthening ribs of different depths disposed crosswise to
each other, so as to afford a freer access of air for supporting combustion.
The juxtaposition of these perforated units or parts laid over the surface of the
furnace, somewhat after the fashion of tiles, constitutes the fuel bearing surface.
Each square or unit forms a separate casting, the upper surface of which is
designed to receive the fuel and is left even or plain, whilst its underside is formed
by a series of longitudinal and transverse ribs disposed perpendicularly, or at right
angles or thereabouts to each other.
These ribs, which are varied in depth according to the greater or less importance
in affording the required resistance of the grating or unit, have spaces or openings
left between them to allow the necessary air to pass through, which spaces or
openings are also formed in directions at right angles to each other like the ribs
which produce them.
The series of units or squares may rest on bearers fixed at suitable distances
apart and parallel or thereabouts with each other, such bearers being bevelled or
reduced in thickness along their upper edges or lines of contact with the units or
squares, so as to offer as little obstruction as possible to the access of air to the said
units.
The said bearers may be placed horizontally or in a more or less inclined position,
so as to form a horizontal or inclined grate suitable for adaptation to furnaces or
fire-places generally. A grate or fuel bearing surface is thus obtained composed of
separate units or squares, each formed with ribs and openings at right angles to
one another in such a manner as to ensure the free access of air to the entire bed
of fuel resting on the said surface.
This distribution of the air is effected in a perfect manner without interfering
with the solidity or strength of the grate, care having been taken to provide the
underside of the units with ribs suitably proportioned to the part they have to
play in affording the general strength or resistance of the arrangement. This
arrangement, whilst assuring the strength and solidity, admits of a considerable
reduction in the weight of the grate, which contains no useless material, since it is
exclusively formed of the said ribs.
To enable the squares or units (which require to be removed for any cause owing
to wear or for cleaning) to be changed a convenient hooked tool has been devised,
the extremity of which is curved in such a fashion as to embrace the ribs of the

page_text: unit, thereby facilitating the operation of removing any one or more of the
same.
The following advantages are derived from the said improved construction of
grate or fuel bearing surface:-
1. Easy adaptation to furnaces and fire places of all forms and sizes, since it is
simply requisite to construct the unit of the grate in the desired proportions and
to place the supporting bearers at the required distance apart. The units instead
of being square or rectangular may, if desired, consist of parallelopipeds, or bo
more or less rounded to adapt them to all kinds of furnaces, such as boiler furnaces,
stoves, and the like.
2. The access of air is such that the air is in close contact with all parts of the
fuel, thereby admitting of the burning of the fuel to the bottom, whatever may be
its nature, and whether in the form of fragments or dust.
The air being in the closest contact with the fuel facility is afforded for burning
innferior combustible materials which cannot be used with ordinary grates.
In addition to coal of all kinds and qualities the improved grate is also capable
of burning anthracite, peat, wood, and the like, in lumps and various sized
fragments.
3. The same faculty which the improved grate possesses of affording a ready
access and a free circulation of air renders the employment of blowers of any kind
unnecessary.
4. The improved grate by allowing the air to pass freely and to present itself on
all points of its comparatively slight or thin surface (it. being only constituted by
the ribs above mentioned), it follows that none of the parts will become overheated
or burnt, but on the contrary will all remain at a comparatively low temperature.
This is of great importance for two reasons, a, it assures to the improved grate
greater durability, since it is less exposed to the causes of destruction of ordinary
grates; b, the clinkers are not liable to adhere to it, which admits of the fireman
cleaning it more readily, whilst obviating the necessity for so active and careful a
surveillance of the fire itself.
Hence it follows that the proper action of the furnace depends considerably less
on the ability of the fireman, and that the said grate can be much more easily
managed.
5. The combustion of the fuel being complete owing to its closer contact with
the air, which passing regularly and easily through the grate, it follows that
when the products of combustion enter the flues or tubes they do not carry with
them particles of fuel or scale, and consequently the flues do not throw off sparks,
which are always more or less dangerous.
Moreover furnaces supplied with this improved grate will be found to consume
the smoke, since the access of air is always effected under the best conditions for
assuring as perfect a combustion as possible.
6. Owing to the peculiar construction and improved action and arrangement of
this grate a considerable economy in the consumption of fuel is effected, and
also an important saving in the furnaces of locomotives, as proved by actual
experiment, which economy can be increased in a great number of other furnaces.
7. Besides the direct economy resulting from a reduced consumption of fuel, the
same experiments have proved that the said improved grate realises a further
saving, which results from the greater quantity of water evaporated in the
same boiler in a given time, whilst the required pressure is more rapidly
obtained.
This fact is important, since it allows of the augmenting of the useful effects
in a given boiler by the simple substitution of the improved for the ordinary
grate.
8. The weight of the improved grate is considerably less than that of ordinary
grates of equal area.
The results from the fact that the material is usefully employed throughout, and
.

page_text: that the improved grates remain cool and do not require, as in the ordinary grates,
additional material to prevent distortion. Consequently in the case of a locomotive
furnace, for example, an ordinary grate weighing, say, 1500 kilogrammes can be
replaced by a grate of the improved arrangement weighing not more than 570
kilogrammes.
Another source of economy is the fact that the improved grates last much longer,
since, as before stated, they do not become heated and are consequently enabled to
resist for a longer period the destructive action of the fire.
And in order that the said Invention may be fully understood, I shall now
proceed more particularly to describe the same, and for that purpose shall refer to
the several Figures on the explanatory Sheet of Drawings hereunto annexed,. the
same letters of reference indicating corresponding parts in all the Figures.
Figure 1 of the annexed Sheet of Drawings is a top view or plan of one of the
units or squares detached which compose the improved grate.
Figure 2 is a plan of the underside thereof; Figures 3 and 4 are vertical sections
taken respectively along the lines 1, 2, and 3, 4, in Figure 2.
These Figures indicate clearly that the grate is composed of a frame of the form
of a parallelogram divided longitudinally by the ribs N, and transversely by the
ribs N'; these latter ribs are furnished with other ribs n and n¹ of various heights,
seen in face view in Figure 3, and in section at Figure 4. The section of these
different ribs may be rectangular, triangular, or otherwise shaped, according to
the nature and quality of the fuel.
The said ribs should always be vertical whether the grate be horizontal or
inclined.
The projections b are for the purpose of maintaining a certain clearance between
the adjoining edges of each part or unit of the grate when laid together side by
side for the freer access of air.
Figures 5, 6, and 7, illustrate by way of example the application of the improved
grate to a locomotive furnace.
On the angle irons C, fixed on the inside of the fire box F, rest the bearers L,
connected in pairs by the cross ties or stays E.
The units of the grate rest directly in these bearers, stops t cast on the undersides
of the squares or units preventing their transverse displacement, and serving as
guides in mounting and dismounting them.
The upper exterior angle a of the bearers L is removed or bevelled off (see
Figure 7) so as to present less obstruction to the air necessary for combustion.
Figures 8 and 9 represent the before mentioned hook or tool for introducing and
removing the grate units or squares. This tool has a long stem terminated by a
handle P, and is bent at its opposite end according to the different heights of the
ribs of the units, so as to form a hook for holding them with greater surety.
I do not confine or restrict myself to the particular mode hereinbefore described
of supporting the peculiar gratings, squares, or units, as various means may
obviously be employed for fitting and supporting the same without departing from
the essential features of this Invention.
i
Having now described and particularly ascertained the nature of the 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 hereinbefore in part
recited Letters Patent is,-
First. A grate or fuel bearing surface for industrial and domestic furnaces or
fireplaces of all kinds, composed of rectangular or any other suitably shaped
gratings of the construction herein specified, which, either singly or combined
together as units, form the surface on which the fuel is placed, substantially as
herein before described and illustrated by the Drawings annexed.
Secondly. The peculiar construction of gratings, squares, or units composed of
strengthening ribs of different depths, and crossing each other at convenient angles,

page_text: leaving openings or spaces at corresponding angles between them to facilitate the
access of air, and its close contact with the fuel, as herein before described and
illustrated by the Drawings annexed.
In witness whereof, I, the said Edwin Powley Alexander, have hereunto set
my hand and seal, this Fifteenth day of June, in the year of our Lord One
thousand eight hundred and eighty one.
EDWIN P. ALEXANDER. (L.S.)