An Improved Chimney Top and Ventilator for the Prevention of Back Drafts.
Year: 1894

page_text: Date of Application, 20th Aug., 1894
Complete Specification Left, 20th May, 1895-Accepted, 22nd June, 1895
PROVISIONAL SPECIFICATION.
An Improved Chimney Top and Ventilator for the Prevention of
Back Drafts.
FREDERICK JACKS 21 Edge Vale Liverpool General Dealer do hereby declare
the nature of this invention to be as follows:-
To consist of an iron square or round box with four opening and closing doors
and closed top with stays from one door to another so when the wind closes one it
open the other with flanges at each side of the doors and one flange at the bottom
of each door.
1004
FREDERICK JACKS,
21, Edge Vale, Liverpool.
An Improved Chimney Top and Ventilator for the Prevention of
Back Drafts.
1, FREDERICK JACKS, formerly of 21, Edge Vale, Liverpool, and at present
of 147, Crown Street, Liverpool, General Dealer, 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 :-
A chimney top or ventilator according to this invention consists of a vertical
casing preferably formed of galvanized iron or other metal and provided with a
hood and two or more side apertures for the egress of smoke or foul air. The
casing may be cylindrical, square, hexagonal, or other section. The apertures are
arranged diametrically opposite to each other in pairs and are each provided with
a hinged door. Each pair of doors are connected together by a rigid stay, the
length of which is such that when one door is closed the opposite door is opened.
Wing flanges or wind guards project radially from the casing between each door,
and another flange is provided below the doors.
In the drawings hereto annexed
Figure 1 is a sectional view of a chimney top or ventilator according to this
invention, Figure 2 being a cross section of same.
Figures 3, 4 and 5 represent a multiple form of chimney top arranged for a stack
of chimneys.
With reference to Figures 1 and 2 of the drawing, a represents the casing of the
chimney top or ventilator. bare apertures provided therein for the egress of smoke
or foul air, and c are hinged doors arranged to cover such apertures, opposite doors
being coupled together by the stays d. e are radial wing flanges or wind guards,
and is a circular inclined flange arranged below the doors.
The action of the chimney top or ventilator is such that when the wind is
blowing in the direction of the arrows A in Figures 1 and 2, the doors c on the
windward side of the chimney top are closed by the wind, and as each pair of doors
are coupled together by a rigid stay d the doors on the opposite or leeward side

page_text: are consequently opened and egress is allowed to the smoke or foul air on such
leeward side. It will be seen that the wind is prevented from blowing down the
chimney by the doors on the windward side of the chimney being closed by the
wind itself. The radial flanges or wind guards e prevent the wind from getting
behind the doors c, and together with the bottom flange f assist to direct the wind
against the front of the doors.
Figures 3, 4 and 5 represent a chimney top according to this invention arranged
in multiple for a stack of chimneys. Each pair of doors c are coupled together
by a stay d as in the first example. This chimney top is also provided with side
and bottom flanges or wind guards e and f, and the action of the apparatus is
identical with that described in reference to Figures 1 and 2.
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 employment in a chimney top or ventilator of hinged doors covering side
apertures therein arranged opposite to each other in pairs and coupled together
by rigid stays in such a manner that when the door on the windward side of the
apparatus is closed by the wind the opposite or leeward door of each pair of doors
is opened for the egress of smoke or foul air, substantially in the manner herein
described.
2. A chimney top or ventilator comprising a casing provided with a hood and
side apertures arranged opposite to each other in pairs the doors of each pair of
apertures being coupled together by a rigid stay in such a manner that when one
door of a pair is closed the other door is open, and side and bottom flanges or
wind guards, arranged and adapted to operate substantially in the manner
described.
1
J. A. COUBROUGH,
Registered Patent Agent, 10, St. George's Crescent, Liverpool,
Agent for the Applicant.