AN IMPROVED. HEAT EXTRACTOR
Year: 1857

page_text: LETTERS PATENT to Robert Hazard, Engineer, of No. 1, Thanet Place;.
Strand, in the County of Middlesex, for the Invention of "AN IMPROVED.
HEAT EXTRACTOR."
Scaled the 13th October 1857, and dated the 14th April 1857.
PROVISIONAL SPECIFICATION left by the said Robert Hazard, at the
Office of the Commissioners of Patents, with his Petition, on the
14th April 1857.
I, ROBERT HAZARD, Engineer, of No. 1, Thanet Place, Strand, in the
County of Middlesex, do hereby declare the nature of the said Invention
for "AN IMPROVED HEAT EXTRACTOR," to be as follows:-
The nature of my Invention consists of an apparatus for intercepting the
waste heat from the smoke or heated gases of every description of furnace,
stove, or kiln, thus economising heat, and affording a great security against
fire from over-heated flues, &c.
The apparatus is composed of a series of cast-iron plates, with any number
of holes that may be required in each plate, and so formed that when bolted-
together they form a number of continuous tubes for the smoke or heated:
gases to pass through in passage from the furnace to the chimney, while the
plate will increase the radiating surface over which the cold air is brought to
become heated. Or it may be formed of a number of cast-iron pipes open.
at each end, and secured to iron plates; thus a pair or more of either.

page_text: horizontal or perpendicular plates held together by open pipes. These are
so placed that all the smoke or heated gases of the furnace, stove, or kilu
must travel through them, over tho external surface of which cold air passes to
become licated.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Robert Hazard in the Great Seal Patent Office on the
14th October 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
HAZARD, Engineer, of No. 1, Thanet Place, Strand, in the County of Middlesex,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of April, in the year of our Lord
One thousand eight hundred and fifty-soven, in the twentieth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Robert Hazard, Her special licenco that I, the said Robert Hazard,
my executors, administrators, and assigns, or such others as I, the said
Robert Hazard, 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 Invention for " AN IMPROVED HEAT
EXTRACTOR," upon the condition (amongst others) that I, the said Robert
Hazard, my executors or administrators, by an instrument in writing under
my, or their, or one of their hands and seals, should particularly describo
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 Robert Hazard, do hereby declaro
the nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement and accompanying Drawings, that is to say:―
My Invention of an improved heat extractor consists of two branches, one
being that of arresting by its use the heat contained in the smoke, gases, &c.,
which are usually allowed to pass off from the fires of steam boilers, kilns, or s
other furnaces to the chimney. The other branch consists of the application

page_text: of a separate fire to the heat extractor in such form and manner as the case
requires. This object is effected by conveying the gaseous products of com-
bustion in its way to the chimney (whether from an existing fire or one
combined with the heat extractor) through iron or other pipes forming the
.extractor, by which means they will become heated, and on a current of cold
air passing around and impinging on their outer surface the heat will be taken
up and carried off.
The accompanying Drawing exhibits various methods of the application of
this principle to the heating of buildings, drying stoves, and other purposes.
In all the Figures the same letters of reference denote the same in similar
parts, wherever they occur throughout the Drawing.
Fig. 1 shews a perspective view of the improved heat extractor, which con-
sists of a pair of flat cast-iron plates A, A, with sockets to receive the ends of.
the pipes a, a, a, a, in which they are jointed smoke-tight by iron cement in.
the usual manner; Bis a soot door and frame, set in the brickwork at
a convenient distance from the extractor, to be opened occasionally so that the
pipes may be cleaned.
Fig. 2 represents the extractor in section, fixed over its own furnace. C is
the fire-place, from whence the smoke, &c. pass through the pipes to the
chamber inside the soot door, thence to the smoke pipe D and chimney E.
From the cavity F, which receives external air to bo heated, it ascends by the
sides of the furnace and horizontal flue, and passing over the top of the furnaco
and flue ascends around and between the pipes of the extractor into the spaco
G, from which it is conveyed away by air flues in any direction that may be:
required.
Fig. 3 is a perspective longitudinal section of a hot plate for cooking, to which
the extractor is applied. C is the furnace, from which the smoke, heat, &c.
pass along tho flue c, c, and enter the ends of the pipes a, a, reaching tho space
D, and thence to the chimney E. The external air entering at F passes
up between the pipes, and becoming heated, as before described, passes off
sideways, and is conveyed away where required.
Fig. 4 represents a section of an ordinary steam boiler, C being the furnace,
from which the heated vapours pass along under the boiler, round its sides,
then through the pipes a, a, a, a, of the extractor into the chimney D. The
air enters around the pipes a, a, from the outside by the channel E, becomes
heated by impinging on the outside of the pipes, and is then led away to
wherever it is required from the chamber above.
Fig. 5, a section of an upright circular furnace case, from which the smoke,
&c. pass along the horizontal outlet U, and into the top of a similar circular
:

page_text: case containing vertical tubes or pipes a, a, through which it descends and
escapes to the chimney. The external air enters around the circumferenco
near the bottom, and in ascending amongst the pipes becomes heated and
escapes. See the arrow at g.
Fig. 6 represents the section of a vertical furnace case with an extractor on
the top, the smoke, heated air, &c. passing from the fire at C up through the
pipes a, a, thence to the chimney, whilst the external air becomes heated by
radiation from the outside of the pipes.
Another modification of the improved extractor is shewn by Fig. 7, of which
Fig. 8 is a horizontal section. Any convenient number of these plates being
united together by the sockets of one plate being inserted into the rebates.
of the next throughout the series, and the joints made tight with cement, and
all bolted together by stretching bolts, the combined sockets will form pipes for
the conveyance of the smoke, &c. in its passage to the chimney, whilst the air
in passing around and between the sockets and plates will be subjected to the
influence of a large amount of heating surface; this extractor to be set in a
brick chamber, the air entrance at the bottom and exit at the top, as before
described for the other Figures.
Fig. 9 is a pan, of any shape required, to be fixed in the hot-air chamber,.
with a branch K, passing through the brickwork to the outside, into which
water is poured, so as to fill the pan until it runs out at the overflow pipe L.
The object of this water pan is to supply a humid atmosphere when required.
I do not confine myself to any particular form of extractor, but to the
general principle of passing smoke, &c. through pipes in its passage to the
chimney and intercepting the heat from the outside, as herein described.
In witness whereof, I, the said Robert Hazard, have hereunto set my
hand and seal, this Fourteenth day of October, in the year of our
Lord One thousand eight hundred and fifty-seven.
ROBERT HAZARD. (L.S.)