Improvements relating to Ventilating Cowls.
Year: 1897

page_text: Date of Application, 28th Oct.,
1897
PROVISIONAL SPECIFICATION.
Improvements relating to Ventilating Cowls.
I, WILLIAM THOMAS SUGG, of Regency Street, in the City of Westminster,
Engineer, do hereby declare the nature of this invention to be as follows:
In the Specification of my Patent No. 1346 of 1890, I described means for ensur-
ing an up-draught in a ventilating shaft, which consisted essentially in adapting
to the top of the shaft a chamber of larger diameter, closed at top by a perforated
cover provided with tubes, and a flat plate arranged a short distance above the
outlets of the tubes and parallel with the cover, the idea being, that a slight move-
ment of the air across the mouths of the tubes, would cause a suction, and produce
a vacuum in the shaft, which would immediately be filled by an upward rush. of
vitiated air from below, and thus the ventilation of the apartment, would be
ensured, without risk of the currents of air being arrested in any way, and caused
to blow down the tubes.
By a series of exhaustive experiments, I have found that the friction of the air
in the tubes causes a loss in the power of the suction produced, and that therefore
with tubes I do not obtain the best results; and the object of the present invention
is to overcome or to obviate the friction.
In carrying out my invention, I take advantage of the well-known principle
of the expansion of gases after passing through a contracted opening, and I provide
a number of inverted pyramidal, conical, or taper-shaped passages in the cover
of the chamber..
".
These passages may be formed by means of a series of triangular shaped pieces
set at convenient distances apart across the top of the chamber, with similarly
shaped stays or dividing pieces at right angles thereto, so that, in plan view, a
diaper pattern will be presented.
Or I may insert truncated cones in an inverted position in the perforated cover
above referred to.--
I do not, however, intend to confine myself to the exact methods of producing
these expanding passages, as above described, which are given by way of example
only.-
By these means, the friction is reduced to a minimum, as the only point where
friction can practically take place is at the inlet to the expanding passage.
Dated this 28th day of October 1897.
NEWTON & SON,
Agents for the Applicant.

page_text: Improvements relating to Ventilating Cowls.
I, WILLIAM THOMAS SUGG, of Regency Street, in the City of Westminster,
Engineer, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement:-
In the Specification of my Patent No. 1346 of 1890, I described means for ensur-
ing an up-draught in. a ventilating shaft, which consisted essentially in adapting
to the top of the shaft a chamber of larger diameter, closed at top by a perforated
cover provided with tubes, and a flat plate arranged a short distance above the
outlets of the tubes and parallel with the cover, the idea being, that a slight move-
ment of the air across the mouths of the tubes, would' cause a suction, and produce
a vacuum in the shaft, which would immediately be filled by an upward rush of
vitiated air from below, and thus the ventilation of the apartment would be
ensured, without risk of the currents of air being arrested in any way and caused
to blow down the tubes.
By a series of exhaustive experiments, I have found that the friction of the air
in the tubes causes a loss in the power of the suction produced, and that therefore
with tubes I do not obtain the best results; and the object of the present invention
is to overcome or obviate the friction.
In carrying out my invention, I take advantage of the well-known principle
of the expansion of gases after passing through a contracted opening, and I provide
a number of inverted pyramidal, conical, or taper-shaped passages in the cover
of the chamber.
These passages may be formed by means of a series of triangular shaped pieces
set at convenient distances apart across the top of the chamber, with similarly
shaped stays or dividing pieces at right angles thereto, so that, in plan view, a
diaper pattern will be presented.
Or, I may insert truncated cones in an inverted position in the perforated cover
above referred to.
I do not however. intend to confine myself to the exact methods of producing
these expanding passages, as above described, which are given by way of example
only.
By these
means, the friction is reduced to a minimum, as the only point where
friction can practically take place, is at the inlet of the expanding passage.
In the accompanying drawings, I have shown several plans for carrying out
my invention.
Fig. 1 shows, in sectional elevation, the general construction of the cowl, with
one form of my invention applied thereto,-The remaining figures will be more
particularly referred to as the description proceeds.
For convenience, what I shall term the suction surface is preferably made
separate from the ventilating shaft, and is enclosed within a ring frame, so that
it can be dropped into the top of the ventilating shaft, which will be suitably pre-
pared to receive it; thus, in all the figures, a, will represent this ring frame.
In Fig. 1, 6 6 represent cross bars which extend from side to side of the frame a.-
These bars are diamond-shaped in cross section, the expansion of the air taking
place after passing the restricted position 61. At right angles to these bars, Ï
place other bars or pieces c, as shown at Fig. 2, so as to produce a number of rect-
angular shaped openings with splayed mouths.
Or, I may place a single diamond shaped bar across the centre, as shown at d,
Fig. 3, at right angles to the bars b.

page_text: Instead of the diamond shaped bars, I may use strips of metal e, set at an angle,
nd at suitable distances apart, as shown in the plan view and section Figs. 4 and 5,
as to form the taper passages f.-These strips e are steadied at the centre of
heir length by the stay or stays e¹, of the same depth as the strips e.-Between
he strips forming the taper passages f, I find it convenient to leave a slight
pace, as shown at e².
In Figs. 6 and 7, the strips e are arranged in concentric circles, supported by
he stays el, as before described.
In Figs. 8 and 9, I have shown an adaptation of truncated inverted cones for
he purposes of my invention.
In this case, the frame a carries a perforated plate g, in the holes of which the
cones h are inserted, the supplementary holes g₁ serving to let air into the spaces
between the cones, which might otherwise act as vacuum spaces, and impede the
suction. The suction power of this cowl is very considerable, and it is found that
it will act with the wind blowing in any direction, even down on the top of it,
without risk of blowing down the shaft or chimney.--
I may here remark that although my primary object is to produce a ventilating
cowl, my invention may obviously be applied to a chimney cowl, as there are no
moving parts to become clogged with soot, a tap or two with the sweep's broom
serving to shake or knock out any soot that may have collected in the openings.
When a fire is not alight, this cowl will act as a ventilating cowl, and will no
doubt have a tendency to prevent down draught.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is;-
1. The use of a series of splayed out or expanding passages in the outlet of a
cowl, for the production of a "suction surface," as and for the purpose set forth.
2. In a cowl, the combination of a series of splayed out or expanding passages,
with a plate arranged parallel with the outlets of the passages, as and for the
purpose set forth.
3. The means herein shown and described for producing a suction cowl.
1
198th day of March 1898.
0 SON