IMPROVEMENTS IN CHIMNEY TOPS, WHICK IMPROVEMENTS ARE ALSO APPLICABLE TO COVERINGS FOR VENTILATING SHAFTS OR FLUES FROM MINES AND OTHER PLACES
Year: 1863

page_text: LETTERS PATENT to Thomas Dobb, of Rotherham, in the County of
York, for the Invention of "IMPROVEMENTS IN CHIMNEY TOPS, WHICK
IMPROVEMENTS ARE ALSO APPLICABLE TO COVERINGS FOR VENTILATING SHAFTS
OR FLUES FROM MINES AND OTHER PLACES."
Sealed the 12th February 1864, and dated the 18th August 1863.
PROVISIONAL SPECIFICATION left by the said Thomas Dobb at the
Office of the Commissioners of Patents, with his Petition, on the 18th
August 1863.
I, THOMAS DOBB, of Rotherham, in the County of York, do hereby declare
the nature of the Invention for "IMPROVEMENTS IN CHIMNEY TOPS, WHICH
IMPROVEMENTS ARE ALSO APPLICABLE TO COVERINGS FOR VENTILATING SHAFTS OR
FLUES FROM MINES AND OTHER PLACES," to be as follows:-
This Invention has for its object improvements in chimney tops, which
improvements are also applicable to coverings for shafts or flues from mines
and other places. For these purposes the top, which is to be placed on the
upper end of a chimney or other flue, is made in two parts, one above the
other, an opening being left between the two; the lower part is by preferenco
made funnel shaped, that is to say, it is made conical, the larger diameter of
the cone being uppermost; the upper part is also conical, the larger diameter
of this cone is downwards. The two cones are connected together at a slight
distance apart from each other, leaving an opening between them. The top
of the upper cone has also a passage through it, and across this passage
horizontal face wheel is placed, which is capable of revolving on a suitable
д

page_text: axis. Outside the two cones is placed a conical hood or guard, which is open
both at the top and bottom; the larger diameter of this conical hood is down-
wards, and its lower end projects below the space or opening between the two
parts of the pot; any wind that enters the bottom of the hood or guard will
rise up the guard, and either escape at the open top of the guard, or, if any of
the wind passes through the opening between the two parts of the pot it will
rise up, and pass through the fan wheel, thus aiding to drive it, and so increase
the current or draught up the chimney or flue. Any wind passing down
through the top of the guard will be unable to enter the opening between the
two parts of the pot, but will pass away through the bottom of the guard;
the wind will thus be prevented from blowing down the chimney or flue.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Dobb in the Great Seal Patent Office on the
18th February 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, TшомAS
DOBB, of Rotherham, in the County of York, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighteenth day of August, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty-seventh year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Thomas Dobb, Ier special licence that I, the said Thomas
Dobb, my executors, administrators, and assigns, or such others as I, the said
Thomas Dobb, 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,
excrcise, and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
CHIMNEY TOPS, WHICH IMPROVEMENTS ARE ALSO APPLICABLE TO COVERINGS FOR
VENTILATING SHAFTS OR FLUES FROM MINES AND OTHER PLACES," upon the con-
dition (amongst others) that I, the said Thomas Dobb, 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.

page_text: NOW KNOW YE, that I, the said Thomas Dobb, do hereby declare the
nature of the 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 thereof, that is to say:-
This Invention has for its object improvements in chimney tops, which
improvements are also applicable to coverings for shafts or flues from mines
and other places. For these purposes the top which is to be placed on the
upper end of a chimney or other flue is made in two parts, one above the
other, an opening being left between the two. The lower part is by preference
made funnel shaped, that is to say, it is made conical, the larger diameter of
the cone being uppermost; the upper part is also conical, the larger diameter
of this cone is downwards; the two cones are connected together at a slight
distance apart from each other leaving an opening between them, the top of
the upper cone has also a passage through it, and across this passage a
horizontal fan wheel is placed, which is capable of revolving on a suitable
axis. Outside the two cones is placed a conical hood or guard, which is open
both at the top and bottom. The larger diameter of this conical hood is
downwards, and its lower end projects below the space or opening between
the two parts of the pot, any wind that enters the bottom of the hood or
guard will rise up the guard and either escape at the open top of the guard,
or if any of the wind passes through the opening between the two parts of
the pot it will rise up and pass through the fan wheel, thus aiding to drive it,
and so increase the current or draught up the chimney or flue. Any wind
passing down through the top of the guard will be unable to enter the opening
between the two parts of the pot, but will pass away through the bottom of
the guard, the wind will thus be prevented from blowing down the chimney
or flue.
"
And in order that my Invention may be fully understood, I will proceed to
describe the Drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS.
Figure 1 of the Drawings hereunto annexed shows a vertical section of a
chimney top, constructed in the manner above described.
a, is the upper conical part of the pot that is open both at the top and
bottom, at its top it carries a horizontal fan wheel b, capable of revolving on
a suitable pin or axis as is shewn; beneath this cone and at a short distance
apart from it is another cone c, the piece c, may, however, if preferred, be
cylindrical, or it may be coned in the opposite direction, the lower end of the
cone c, is connected to the upper end of a flue or chimney; the cones a and c

page_text: are connected together at intervals by pieces d, d; e, is the conical hood or
guard placed around the upper part a, the lower end of this hood or guard
projects downwards below the space between the two parts a and c, and the
guard is open both at the top and bottom, the larger diameter of the cone is
also downwards as is shewn. By these means, as before stated, any wind that
enters the bottom of the hood or guard will rise upwards, and the portion of
the wind that passes upwards through the opening between the parts a and c
will drive the fan b, and so increase the current or draft up the chimney or
flue. Figure 2 shows a vertical section of a chimney top slightly modified
from that above described, but in which the fan wheel b, carried at the top of
the conical part a, is driven as in the former arrangement by any wind that
rises upwards through the space between the two parts a and c. Figure 3,
is a side view of the pot shewn in Figure 2, and Figure 4, is a plan view of
the same.
In Figures 2, 3, and 4, the parts similar to those shewn in
Figure 1, are marked with the same letters of reference. In the chimney
top represented at Figures 2, 3, and 4, the upper part a of the pot, and the
hood or guard e have no space between them, as described in the arrange-
ment shown at Figure 1, so that all the wind that rises up through the
bottoin of the guard must pass by the fan and aid in driving it. If desired
the parts a and c may in this arrangement be formed together in one piece, a
in place of being separate as is shewn; the guard e is connected to the
upper end of the part c by strips d, d, as is shewn. The manner in which
it is preferred to carry the fan wheel b, is shewn clearly in the plan view
Figure 4.
In witness whereof, I, the said Thomas Dobb, have hereunto set my
hand and seal, this Sixteenth day of February, in the year of our
Lord One thousand eight hundred and sixty-four.
S
Witness,
EDWARD BARTLE.
THOMAS DOBB. (L.S.)