SPIRAL UPDRAUGHT EXHAUST CHIMNEY COWL AND ROOF VENTILATOR
Year: 1884

page_text: I ARTHUR CHARLES SMITH, Carpenter, of 114 Wells Street Camberwell in the
County of Surrey do hereby declare the nature of my Invention for SPIRAL
UPDRAUGHT EXHAUST CHIMNEY COWL AND ROOF VENTILATOR to be as follows:-
My Invention relates to apparatus to be applied to the upper part of chimney
and ventilating shafts, for increasing updraught, and preventing downdraught.
In carrying my Invention into effect, I provide the upper part of the chimney
or ventilating shaft, with a head, constructed with any required number of
concentric guard rings, all of the same diameter, and each ring tapering in itself,
inward and upward, and with a narrow depending band fixed round the outter
edge, and a narrow upstanding band fixed round inner edge of each. The width
of said guard rings is determined by the diameter of main shaft, a vertical passage
through centre of guard rings forming head being kept clear, about one third less
the diameter of main shaft.
The first or lower guard ring is fixed concentrical, and partly overlapping top
portion, or part of main shaft, all others are arranged concentrical one over the
other, and at such a distance from each other, that the outter current of air may
pass through the open space into centre of head, and at the same time preventing
the rain entering. In spaces between said guard rings and fixed at equal distances
round upper slope of one and reaching to under slope of the guard ring above,
are a number of vertical guard plates, each of sufficient width to reach in an oblique
direction from outter to inner edge of said guard rings.
The said vertical guard plates may be either inclined to the right or to the left of
common centre of head, but in one and the same head all must incline in the same
direction.
The result of above explained construction of apparatus, is, that the outter
current of air entering the open spaces between horizontal guard rings and
vertical guard plates, is forced through in a powerfull upward current in a
direction inclined round axis, thereby creating a spiral updraught exhaust to
chimney or ventilating shaft.
At the top or upper part of head, is a conical cap, with a depending curtain or
band, and supported a short distance above the uppermost guard ring, but when
used as a chimney cowl, it may or may not have a cap.
The apparatus constructed as described may be used as a chimney cowl, or roof
ventilator, and made of any suitable material, or may have a suitable perforated
and more ornamental casing of any material.
Dated this 5th day of January 1884.

page_text: I ARTHUR CHARLES SMITH of 114 Wells Street Camberwell in the County of
Surrey Carpenter, do hereby declare the nature of my Invention for SPIRAL
UPDRAUGHT EXHAUST CHIMNEY COWL AND ROOF VENTILATOR and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
My Invention relates to apparatus to be applied to the upper part of chimney or
ventilating shafts for increasing updraught and preventing downdraught, and is
shewn by the accompanying Sheet of Drawings of which Figure 1 is an elevation,
Figure 2 a transverse section on line 1. 1, Figure 1, Figure 3, a vertical section on
line 2. 2, Figure 2. The same letters of reference indicating corresponding parts in
all the Figures.
In carrying my Invention into effect I provide the upper part of chimney or
ventilating shaft with a head constructed with any required number of conic
guard rings B each of the same diameter and tapering inward and upward with a
narrow depending band C, fixed round outer edge and an upstanding band D, on
inner edge.
The width of said conic guard rings B, will be determined by the diameter of
main shaft. I prefer a passage being kept clear through head about one third less
the diameter of shaft.
The first of the said conic guard rings B, is fixed concentrical and partly
overlapping top or upper part of main shaft A, all others are arranged concentrical
one above the other and at such a distance from each other that the outer current
of air may pass through the open spaces between into head, and at the same time
will prevent rain entering.
In the spaces between the said conic guard rings B, and fixed at equal distances
round upper slope of one and reaching to under slope of the guard ring above are a
number of vertical guard plates or guides E, each of sufficient width to reach in an
oblique direction from outer edge of guard rings B, to within a short distance of
upstanding band D, on inner edge thereby leaving a space between inner edges of
vertical guard plates or guides E, and upstanding band D, on the uppermost
conic guard rings I fix vertical blades F, as shewn in Drawings.
The said vertical guard plates or guides E, and blades F, may be either inclined
to the right or to left of common centre, but in one and the same head all must
incline in the same direction.
The result of above explained construction of apparatus is that the outer current
of air entering the open spaces between conic guard rings B, and vertical guard
plates or guides E, is forced through in a powerful upward current in a direction
inclined round axis, thereby creating a powerful spiral exhaust to chimney or
ventilating shaft.
The top or upper part of head I may furnish either with a flat covering plate,
or conical, or other shaped cap, with or without a depending curtain or band,
supported with suitable stays a short distance above uppermost ring.
When a cap
with a depending curtain or band is used the vertical blades F, may be dispensed
with. To make it still more effective to exclude rain or snow when used as a
ventilator the upstanding bands D, on inner edge of conic guard rings B, may be
extended to any required distance in an upward direction.
I do not limit myself to the use of the number of conic guard rings, guard plates
or guides, or blades shewn as more or less may be used as found convenient; neither
do I limit myself to the slope of conic guard rings, or the angle at which the vertical
guard plates or guides, or blades may be fixed on conic guard rings.

page_text: The apparatus constructed as described may be used as a chimney cowl and for
general ventilating purposes, and may be made in any suitable material and may
have a suitable perforated and more ornamental casing of any suitable material.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is:-
First A spiral updraught exhaust chimney cowl, roof and general ventilator,
constructed as hereinbefore described and shewn in accompanying Drawings.
Second: An apparatus consisting of any required number of conic rings with
depending and upstanding bands, vertical guard plates or guides, and vertical blades
arranged as herein before described and shewn in accompanying Drawings.
Dated this 3rd day of June 1884.
ARTHUR CHARLES SMITH.