IMPROVEMENTS IN GRATE BARS FOR FURNACES OR FIRE-PLACES
Year: 1875

page_text: LETTERS PATENT to Horatio Walter Ibbotson, of Sheffield, in the
County of York, Gentleman, for the Invention of "IMPROVEMENTS
IN GRATE BARS FOR FURNACES OR FIRE-PLACES."-A communication from
abroad by Thomas Holt, of Trieste. Austria.
Sealed the 13th August 1875, and dated the 20th February 1875.
PROVISIONAL SPECIFICATION left by the said Horatio Walter
Ibbotson at the Office of the Commissioners of Patents, with
his Petition, on the 20th February 1875.
I, HORATIO WALTER IBBOTSON, of Sheffield, in the County of York,
Gentleman, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN GRATE BARS FOR FURNACES OR FIRE-PLACES," a communi-
cation, to be as follows:-
-
The object of my Invention is the construction of the grate floor or
bed of a furnace or fire-place in such a manner that the largest possible
quantity of air may be admitted through it from the under side into or
against the fuel to produce combustion without leaving any spaces in
the grate bars large enough to permit more than the smallest, if any,

page_text: particles of the fuel to fall through or between them unconsumed, so
that the commonest and smallest fuel may be advantageously used and
a more perfect combustion, and consequently a greater heat, will be pro-
duced than has heretofore been practicable. Moreover, a much smaller
number of these grate bars will be required than is ordinarily used, and
the surfaces of the metal exposed to the action of the fire will be so
small and thin and so well supplied with air to keep them cool that they
will be much more durable than ordinary grate bars, and therefore will
be highly economical in use.
According to my said. Invention I form grate bars with the main
bearing portion thereof straight on the top surface, and much thinner
but much deeper than usual, and on one or both sides of the bars, at
their upper edges and level therewith, I form a series of projections.
When a sufficient number of these grate bars is placed in the furnace
or fire-place to fill up the space required for the floor of the fire the pro-
jections on one bar will enter the spaces between the projections of the
adjacent bars, the said bars being very close together but not touching
each other, thereby leaving a multitude of narrow spaces or passages for
the admission of air to the fuel, with a flat surface for the fuel to lie on.
: The ends of these grate bars may be formed to rest on cross bars or
supports, and also with side projections on the said ends, and vertical
tongues and grooves are formed on these projections, so that the ends of
all of the said bars may fit against or lock into each other to ensure their
resting at equal distances apart, with uniform spaces between them over
the whole surface of the floor of the furnace or bed of the fire. Or
instead of making the ends of these grate bars with a tongue on one side
and a groove on the other side, one grate bar may have projections on
both sides, and the next may have sockets on both sides, and so on
throughout the entire series of bars, so that they may all-interlock with
each other. Or the whole of the ends may have plain projections simply
to fit against each other. The ends of these grate bars may be left
hollow underneath to reduce their weight.
:
The aforesaid projecting parts of the bodies of the grate bars need not
be deep or thick, as the air passing through the spaces will keep them
sufficiently cool to prevent their being injured or destroyed by the fire.
These projections on the sides of the grate bars may be of any form
deemed most advantageous for the admission of the largest quantity of

page_text: air through the narrowest and greatest number of spaces, the said
projections may be formed at intervals and with apertures through them;
or instead of a series of projections one continuous flange or projection
with a straight outer edge may be formed on each side of the main
bearing part of the bar, with a series of holes or spaces through the said
projection.
The grate bars may be cast in steel or other suitable metal, or may be
formed of rolled or forged steel or iron, but I prefer to make them of
cast iron, with the main bearing part cast very thin but deep to make
them strong, or with a deep web, preferably deepest at the centre of the
bars, and both the web or under part and the said projections for
forming the air spaces or passages should be slightly taper, so that they
may be easily, expeditiously, and cheaply moulded in sand. The sides
of those grate bars which are intended to fit against the sides of the
furnace, grate floor, or bed, I prefer to leave plain or straight, that is to
say, without the said projections.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Horatio Walter Ibbotson in the Great Seal Patent
Office on the 19th August 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HORATIO
WALTER IBBOTSON, of Sheffield, in the County of York, Gentleman, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twentieth day of February, in the year
of our Lord One thousand eight hundred and seventy-five, in the
thirty-eighth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Horatio Walter Ibbotson, Her
special licence that I, the said Horatio Walter Ibbotson, my executors,
administrators, and assigns, or such others as I, the said Horatio
Walter Ibbotson, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all
times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man, an

page_text: Invention for “IMPROVEMENTS in Grate Bars FOR FURNACES OR FIRE-PLACES," a
communication to me from abroad by Thomas Holt, of Trieste, Austria,
upon the condition (amongst others) that I, the said Horatio Walter
Ibbotson, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and .
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Horatio Walter Ibbotson, do :
hereby declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained in
and by the following statement, reference being had to the accom-
panying Drawing forming a part of this Specification:--
The object of my Invention is the construction of the grate floor or
bed of a furnace or fire-place in such a manner that the largest possible
quantity of air may be admitted through it from the under side into or
against the fuel to produce combustion without leaving any spaces in or
between the grate bars large enough to permit more than the smallest, if
any, particles of the fuel to fall through or between them unconsumed,
so that the commonest and smallest fuel may be advantageously used
and a more perfect combustion, and consequently a greater heat will be
produced than has heretofore been practicable. Moreover, a much
smaller number of these grate bars will be required than is ordinarily
used, and the surfaces of the metal exposed to the action of the fire will
be so small and thin and so well supplied with air to keep them cool that
they will be much more durable than ordinary grate bars, and therefore
will be highly economical in use.
Figure 2 is a side elevation or one of the saiu Dars.
Figure 3 is a transverse section on the line x, x, Figure 2.
Like letters indicate the same parts throughout the Drawing.
| According to the said Invention I form the grate bars with the main
bearing portion a thereof straight on the top surface, and much thinner 35

page_text: but much deeper than usual, and on one or both sides of the bars, at
their upper edges and level therewith, I form a series of projections b,
with apertures o through them, and when a sufficient number of these
grate bars is placed in the furnace or fire-place to fill up the space
required for the floor of the fire, the projections 6 on one bar will enter
the spaces between the projections of the adjacent bars, the said bars
being very close together but not touching each other. I thereby obtain
in combination with the apertures ca multitude of narrow spaces or
passages d for the admission of air to the fuel, with a flat surface for the
said fuel to lie on.
The ends of these grate bars may be formed to rest on cross bars or
supports. There aro side projections e on the said ends, and they are
formed with vertical tongues f and grooves g, so that the ends of all
of the said bars may fit against or lock into each other to ensure their
resting at equal distances apart, with uniform spaces d between them
over the whole surface of the floor of the furnace or bed of the fire. Or
instead of making the ends of these grate bars with a tongue on one side
and groove on the other side, one grate bar may have projections on both
sides, and the next may have sockets on both sides, and so on throughout
the entire series of bars, so that they may all interlock with each other.
Or the whole of the ends may have plain projections simply to fit against
each other. The ends of these grate bars may be left hollow underneath
to reduce their weight.
The aforesaid projecting parts 6 of the bodies of the grate bars need
not be thick or deep, as the air passing through the spaces c and d will
keep them sufficiently cool to prevent their being injured or destroyed
by the fire. These projections on the sides of the grate bars may be of
any form deemed most advantageous for the admission of the largest
quantity of air through the narrowest and greatest number of spaces.
The said projections may be formed at intervals on the bars; or instead
of a series of projections I may form on each side of the main bearing
part of the bar one continuous flange or projection, with a straight outer
edge and with holes or spaces through the said projection.
These grate bars may be cast in steel or other suitable metal, or may
be formed of rolled or forged iron, but I prefer to make them of cast
iron, with the main bearing part cast very thin but deep to make them
strong, or with a deep web, preferably deepest at the centre of the bars,

page_text: and both the web or under part and the said projections for forming air
spaces or passages should be slightly taper, so that they may be easily,
expeditiously, and cheaply moulded in sand. The sides of those grate
bars which are intended to fit against the sides of the furnace, grate floor,
or bed, I prefer to leave plain or straight, that is to say, without the said
projections.
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. A furnace bar constructed with projections on one side or on
both sides, and with air spaces or apertures through the said projections,
as herein set forth and for the purpose specified.
Second. A set or series of such bars placed together to form the grate
of a furnace, and kept by end projections or other suitable means in such
a position that the lateral projections on one bar lie between those on
the adjacent bars, and the said grate presents a flat surface for the fuel
to rest upon, and has a series of narrow air apertures or passages between
the said bars in combination with the air apertures formed through the
said projections, as herein set forth and for the purpose specified.
In witness whereof, I, the said Horatio Walter Ibbotson, have here-
unto set my hand and seal, this Eighteenth day of August, in the
year of our Lord One thousand eight hundred and seventy-five.
HATTA TITTAD
רת אחממ
HORATIO WALTER IBBOTSON. (1.s.)