IMPROVEMENTS APPLICABLE TO CHIMNEYS AND VENTILATING SHAFTS
Year: 1879

page_text: LETTERS PATENT to Charles Henry Sharp, of the Hop Exchange, in the County
of Surrey, for the Invention of "IMPROVEMENTS APPLICABLE TO CHIMNEYS
AND VENTILATING SHAFTS."
Sealed the 23rd May 1879, and dated the 10th March 1879.
Sealed the 23rd May 1879, and dated the 10th March 1879.
PROVISIONAL SPECIFICATION left by the said Charles Henry Sharp at the
Office of the Commissioners of Patents on the 10th March 1879.
CHARLES HENRY SHARP, of the Hop Exchange, in the County of Surrey. "Iм-
PROVEMENTS APPLICABLE TO CHIMNEYS AND VENTILATING SHAFTS."
'
My Invention has for its object the prevention of what are commonly called
smoky chimneys, the arrangements also being applicable as a ventilating shaft, and
to the prevention of down draughts in chimneys and ventilating shafts.
In carrying out my Invention, to take the case of a simple chimney shaft, I
place on the top of the shaft a half circular or other suitable shaped dome, the
mouth of which I sometimes prefer to decrease in area to regulate the draught.
The bottom edge of dome is secured to the shaft by a ring, collar, or other suitable
shape or arrangements, which forms a covered surface underneath. This makes the
dome a solid substance or connection to the shaft. I place above the mouth at top
a suitable covering, such as are in ordinary use, and supports which are secured to
the shaft below the dome.
My Invention is so arranged that when the wind is blowing upwards or down-
wards, the foul air or smoke immediately rushes up the shaft, thus securing a
continuous powerful upward current and no down draught.
By this construction of this chimney top or ventilating shaft it can be fixed in
all situations above or below roofs, and at any angle, and will work as effectually
in whatever angle it is placed. It will not interfere with the effectual cleaning of
the shaft.
2

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Charles Henry Sharp in the Great Seal Patent Office on the 10th
September 1879.
CHARLES HENRY SHARP, of the Hop Exchange, in the County of Surrey.
PROVEMENTS APPLICABLE TO CHIMNEYS AND VENTILATING SHAFTS."
"
IM-
My Invention has for its object the prevention of what are commonly called
smoky chimneys, my arrangements also being applicable as a ventilating shaft and
to the prevention of down draughts in chimneys and ventilating shafts.
In carrying out my Invention, to take the case of a simple chimney shaft, I place
on the top of the shaft a half circular or other suitable shaped dome, with a central
opening or mouth, which I sometimes prefer to decrease in area, to regulate the
draught. The bottom edge of the dome is secured to the shaft by a ring, collar, or
other suitable shape or arrangements, forming a covered surface underneath. This
makes the dome a solid substance or connection to the shaft. I place above the
central opening or mouth of the dome at top a suitable covering, secured by supports
to the shaft below the dome, or as may be convenient.
My Invention is so arranged that when the wind is blowing upwards or down-
wards, or between the dome and cap, the foul air or smoke immediately rushes up
the shaft, thus securing a continuous powerful upward current, and preventing
down draught.. This construction of this chimney top or ventilating shaft can be
adopted in various situations above or below roofs, and at various angles, and will
work as effectually in whichever angle it is placed. It will not interfere with the
effectual cleaning of the shaft.
Having thus far described the nature of my said Invention, and incidentally
intimated in what manner the same is to be performed, I will now proceed (aided
by the accompanying Drawings) to further and particularly describe and ascertain
in what manner the same is to be performed or carried out in practice, that is to
Fig. 1 is a section of the ventilating chimney top, made according to my
Invention.
Fig. 2, side elevation.
A, chimney shaft. I place on the top a semicircular or other suitable shaped
dome, having an opening at the top, which I sometimes prefer to decrease or
enlarge in area, to regulate the draught. The bottom edge of the dome is secured
to the shaft by a ring, collar, or other suitable arrangements B', forming a flat surface
underneath. This makes the dome a solid substance or connection to the shaft, but
it can be made as a wind chamber around the shaft A by keeping the shaft down or
raising the dome about two inches above the shaft, with small outlets in collar
underneath the dome, as indicated by the arrangement shown at Fig. 2a. C is a
suitable covering over the mouth, supported by three uprights, secured to the shaft
below the dome. Its outer and upper surfaces are rounded, and the underside flat.
A ventilator can be used with my arrangements, where a more powerful upward
current of air is required for ventilating rooms and other places; and at Fig. 3 an
arrangement of ventilator is shown which I have found suitable for effecting this
object.
.
The chimney top, constructed as herein.described, can be fixed in any situation
below or above roofs, and may be placed horizontally, or at any desired angle, and
can be constructed in zinc, copper, brass, iron, terra-cotta, or other suitable
material

page_text: Having now particularly described and ascertained the nature and object of the
said Invention, and in what manner the same is to be performed, I hereby declare
that I claim the Invention of " Improvements Applicable to Chimneys and Ventilating
Shafts," substantially as hereinbefore described and illustrated by the accompanying
Drawings, wherein the principal and important point or feature is the adoption of
a ventilating chimney top or shaft, constructed with a tubular shaft and dome and
cap or cover, substantially as herein before described and illustrated by the
accompanying Drawings.
In witness whereof, I, the said Charles Henry Sharp, have hereunto set my
hand and seal, this Ninth day of September, in the year of our Lord One
thousand eight hundred and seventy nine.
Witness,
W. HILLIER,
Clerk to Inventors' Patentright Ass², Ld.,
21, Cockspur Street,
London,
S.W.
C. H. SHARP. (L.S.)