AN IMPROVED VENTILATING CAP OR COWL
Year: 1884

page_text: I HENRY HARRIS LAKE of the firm of Haseltine Lake & Co. Patent Agents
Southampton Buildings in the County of Middlesex do hereby declare the nature
of my Invention for "AN IMPROVED VENTILATING CAP OR COWL" and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :—
This Invention relates to an improved ventilating cap or cowl, and comprises the
improvements hereinafter described.
Referring to the accompanying Drawing
Figures 1, 2, 3, 4 and 5 are sectional elevations of flue caps or cowls showing
slight modifications in the form of constructing them.
Figure 6 is a plan view of the cowl shown in Figure 2.
Figure 7 is a plan view of the same with the dome removed.
Figure 8 is a cross sectional view on the line x, x Figure 1.
A, is the inain flue or shaft around which a short distance down from the top is
a projecting flat ring B, and attached to the top of the shaft by bars a, is an
outwardly Haring jacket or shield C, leaving a space i, between it and the flue, the
lower edge of the shield coming below the top of the flue, and the upper edge
coming above the top of the flue, as shown.
D, is a conical top or dome connected to the flue A by standards g, and having
an upturned lower edge b.
The top of the upturned edge b, is about level with the upper edge of the
shield C, leaving a space d, between them.
In Fig. 3 the dome D, is shown without a bottom, while in Figs. 1, 4, and 5, a
downwardly curving. bottom E is shown attached to the dome, and in Fig. 2 the
bottom E is shown conical, with its point downward, but all these modifications
are substantially the same.
In Fig. 5 the flaring jacket C is shown flaring both at the bottom and top, and
an angular plate B¹, is arranged upon top of the ring B, as shown.
In Fig. 4 the upper part of the main flue is shown flaring outward.
The outer edge of the bottom E, slants upward and outward as shown at e, so as
to enable the air, smoke &c., to escape more freely from the flue, and also to prevent
the air currents from being driven down the flue.
•

page_text: By this arrangement the dome D prevents any air currents being driven down
the flue A, while its upturned edge b, catches all the currents which strike the dome
and turns them upward and outward again, thus creating a vacuum in the narrow
throat d, and greatly assisting the draft in the flue.
The same effect is produced by the edge e, and outwardly flaring shield C, when
the currents are blown upward, the band B serving to prevent the air blowing
directly up between the shield and flue.
-The standards g, are shown connected to a ring F, which fits down into the top
of the flue, so that the dome D and bottom E, may be easily removed from the flue
to enable its interior to be reached for cleaning, repairs, &c.
The dome D may be made in a rounded or other form.
The dome may be attached directly to the flue A, instead of to the ring F, under
some circumstances, as in Fig. 4.
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:-
-
A ventilating flue cap consisting of an outwardly flaring shield C surrounding
the upper end of the flue, a ring B surrounding said flue below said shield, and a
dome D having an upturned lower edge b, above said flue and shield.
Dated this
1004
Doted the lat
HASELTINE, LAKE & Co.,
For the Applicant.