IMPROVEMENTS IN REGENERATIVE HOT BLAST STOVES PROVISIONAL SPECIFICATION
Year: 1874

page_text: LETTERS PATENT to Charles Cochrane, of the Grange, Stourbridge, in
the County of Worcester, and Edward Alfred Cowper, of No. 6,
Great George Street, Westminster, in the County of Middlesex, for
the Invention of "IMPROVEMENTS IN REGENERATIVE HOT BLAST STOVES
PROVISIONAL SPECIFICATION left by the said Charles Cochrane and
Edward Alfred Cowper at the Office of the Commissioners of
Patents, with their Petition, on the 8th May 1874.
We, CHARLES COCHRANE, of the Grange, Stourbridge, in the County
of Worcester, and EDWARD ALFRED COWPER, of No. 6, Great George
Street, Westminster, in the County of Middlesex, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN REGENERATIVE
HOT BLAST STOVES FOR HEATING AIR, STEAM, AND OTHER GASES," to be as
follows: :-

page_text: brick surfaces are arranged to act as "regenerators" for absorbing and
giving off heat on the principle set forth in the Specification of a Patent
granted to Frederic Siemens on the 2nd December 1856, No. 2861.
Our present Invention consists in applying to such stoves means of
distributing the volume of flame or products of combustion amongst the
passages in the regenerator in a more perfect manner than heretofore, so
that an equal or nearly equal quantity shall pass through each of the
passages, and also that the cold air on being passed through the heated
regenerator shall likewise be equally distributed and become uniformly
heated, and thus give a higher temperature of blast than heretofore.
For this purpose we construct within the stove a vertical flue which we
prefer to be circular in section for the flame or products of combustion
to ascend from the lower part of the stove to the upper part, and we
place it close to one side of the stove or against the internal brick lining
thereof opposite to the chimney valve. From the upper part of the
stove the flame or products of combustion descend through the
regenerative passages, and thus the total length of passage through any
part of the stove being nearly the same, the flame at the one time and
the air at another time flows with equal freedom through any of these
passages. In order still further to ensure the uniform distribution of
the flow through the passages we form at or near the top of each of the
regenerator passages a contraction which reduces the area of inlet to
such passage and thereby prevents the flow through it of more than its
due share, thus having the effect of dividing up the whole current and
causing it to be distributed more uniformly amongst all the passages,
whereby the action of the stove is rendered more perfect and the blast is
heated to a higher temperature than formerly.
The contractions above described may be arranged so that there may
be slightly different areas through the passages, according to their
position in the stove, the area being somewhat more contracted for
passages which have less total length..
The improvements above set forth are applicable also in stoves em-
ployed for heating gas, steam, or other aeriform fluids, as may be readily
understood.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent
filed by the said Charles Cochrane and Edward Alfred Cowper in
the Great Seal Patent Office on the 6th November 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, CHARLES
COCHRANE, of the Grange, Stourbridge, in the County of Worcester, and
EDWARD ALFRED COWPER, of No. 6, Great George Street, Westminster,
in the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighth day of May, in the year of our
Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto us, the said Charles Cochrane and Edward Alfred
Cowper, Her special license, that we, the said Charles Cochrane and
Edward Alfred Cowper, our executors, administrators, and assigns, or
such others as we, the said Charles Cochrane and Edward Alfred
Cowper, our 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 Invention for "IM-
provements in REGENERATIVE HOT BLAST STOVES FOR HEATING AIR, STEAM, AND
OTHER GASES," upon the condition (amongst others) that we, the said
Charles Cochrane and Edward Alfred Cowper, our executors or admini-
strators, by an instrument in writing under our or their hands and
scals, or under the hand and seal of one of us, or them, 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 Edward Alfred Cowper, on behalf
of myself and the said Charles Cochrane, 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 thereof, reference being had to the accompanying Sheet of
Drawings and to the figures and letters marked thereon, that is to say :-
Our Invention relates to hot blast stoves of the kind used for heating
blast for blast furnaces known as 66
Cowper's stoves," in which fire-brick

page_text: surfaces are arranged to act as "regenerators" for absorbing and giving
off heat on the principle set forth in the Specification of a Patent granted
to Frederic Siemens on the 2nd December 1856, No. 2861.
Our present Invention consists in applying to such stoves means of
distributing the volume of flame or products of combustion amongst the
passages in the regenerator in a more perfect manner than heretofore, so
that an equal or nearly equal quantity shall pass through each of the
passages, and also that the cold air on being passed through the heated
regenerator shall likewise be equally distributed and become uniformly
heated, and thus give a higher temperature of blast than heretofore.
For this purpose, we construct within the stove a vertical flue which we
prefer to be circular in section for the flame or products of combustion
to ascend from the lower part of the stove to the upper part, and we
place it close to one side of the stove or against the internal brick lining
thereof opposite to the chimney valve. From the upper part of the
stove the flame or products of combustion descend through the
regenerative passages, and thus the total length of passage through any
part of the stove. being nearly the same the flame at the one time and
the air at another time flows with equal freedom through any of these
passages. In order still farther to ensure the uniform distribution of
the flow through the passages we form at or near the top of each of the
regenerator passages a contraction which reduces the area of inlet to
such passage, and thereby prevents the flow through it of more than its
due share, thus having the effect of dividing up the whole current and
causing it to be distributed more uniformly amongst all the passages,
whereby the action of the stove is rendered more perfect and the blast is
heated to a higher temperature than formerly.
The contractions above described may be arranged so that there may
be slightly different areas through the passages, according to their.
position in the stove, the area being somewhat more contracted for
passages which have less total length.
The improvements above set forth are applicable also in stoves
employed for heating gas, steam, or other aeriform fluids, as may be
readily understood.

page_text: tight casing of wrought iron; B, the fire-brick lining; C, the vertical
flue; D is. the gas valve, through which gas for combustion is admitted;
E is the air valve for the admission of air for combustion. The flame
produced by the combustion of the gas passes up the vertical flue C and
down through the regenerator F and away to the chimney through the
chimney valve G, as indicated by the arrows. When the stove is
sufficiently heated the gas valve D, the air valve E, and the chimney
valve G, are closed; and the cold blast valve H being then opened the
blast passes through the regenerator F, and down the vertical flue C,
through the hot blast valve I to the blast furnace in the direction
opposite to that indicated by the arrows.
Fig. 3 is a plan, and Fig. 4 is a section to an enlarged scale of a
portion of the regenerator F, which is formed of a number of fire-bricks
placed at a distance apart so as to form small passages through the
mass. Over the top course of bricks tiles K, K, with holes in them are
placed to cause an equal flow of the products of combustion amongst all
the passages.
J is a brush for removing the dust from the passages.
Fig. 5 is a plan, and Fig. 6 is a section of another arrangement of
bricks for the regenerator F. In this case the bricks are placed in lines
crossing each other.
For clearing out any slight dust that may settle in the stove it is con-
venient to blow it out by means of the blast put on at a time when
there is a valve open to the outer air. A convenient mode of doing this
is to provide a second gas valve some distance back in the gas main and
to open a door or valve between this gas valve and that on the stove so
that the dust is blown out of the gas passage.
Having thus described the nature of our Invention and in what
manner the same is to be performed we hereby declare that we do not
claim generally the use of regenerative stoves for heating the blast of
furnaces, but we claim,-
First. The construction of a cylindrical regenerative hot blast stove
with an ascending circular flue near to one side of the stove in com-
bination with a regenerator occupying the remainder of the interior of
the stove, the said flue and regenerator being so arranged that the
5 distances traversed by the different fluid currents passing through the
stove are equal or nearly so, substantially as herein described.

page_text: above, narrowing the apertures to the regenerative passages for the
purpose of equalising the distribution of the fluid streams, substantially
ás herein described.
:
In witness whereof,, I, the said Edward Alfred Cowper, have here-
unto set my hand and seal, this Second day of November, in the
year of our Lord One thousand eight hundred and seventy-
four.
In witness whereof,, I, the said Edward Alfred Cowper, have here-
unto set my hand and seal, this Second day of November, in the
year of our Lord One thousand eight hundred and seventy-
four.
EDWARD ALFRED COWPER. (L.S.)