Improvements in Cowls or Caps for Preventing Downdraught in Ventilating Shafts, Flues, and other Analogous Constructions.
Year: 1886

page_text: Improvements in Cowls or Caps for Preventing Downdraught in
Ventilating Shafts, Flues, and other Analogous Constructions.
I JOHN WATSON, of St. Albans in the County of Herts, Florist, do hereby
declare the nature of my said invention to be as follows:-
The object of my invention is to manufacture an improved form of cowls or
caps for preventing downdraught, in ventilating shafts, flues, and other analogous
constructions.
I construct my improved cowls or caps with two or more concentric cylinders.
The two cylinders are both supported by, and fixed to, and upon, an annular plate,
which plate is supported by the fluc, chimney, pipe, or other air vent (hereinafter
called the "flue") to which it is applied; and the central opening in the annular
plate is made to suit that of the flue.
Vertical plates are placed in or between the cylinders dividing the annular
spaces into two, three, four, or more portions, longitudinally.
The inner cylinders or one of them have, or has, a number of perforations, for
permitting the rising air from the flue to gain access to the annular spaces between
the cylinders.
Openings are also made in the annular plate, below the cylinders, to admit
currents of external air, or to permit the exit of the foul air.
The inner and outer cylinders are stayed and strengthened, where necessary, to
impart the necessary firmness thereto.
The cylinders are finished above with an ornamental or other suitable cover, and
the cylinders have openings under this cover to permit the exit of foul air.
The arrangement of the concentric cylinders, and the number and sizes of the
perforations, as well as other minor details of construction may be very much
varied, to suit the character and purpose of the flues to which they may be
applied.
GEO. DOWNING,
Agent for Applicant,

page_text: Improvements in Cowls or Caps for Preventing Downdraught in
Ventilating Shafts, Flues, and other Analogous Constructions.
I, JOHN WATSON, of St. Albans, in the County of Herts, Florist, do hereby
declare the nature of my said invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
The object of my invention is to manufacture an improved form of cowls or
caps for preventing downdraught, in the chimnies of gas stoves, sewage pipes,
ventilating shafts, flu-s, and other analogous constructions.
I construct my improved cowls or caps with two or more concentric cylinders.
These cylinders are supported by and fixed to and upon an annular plate, which
plate is supported by the flue, chimney, pipe, or other air vent (herein after called
the "flue") to which it is applied; and the pipe below the annular plate is made
to suit the opening in the flue.
Vertical plates are placed in or between the cylinders, dividing the annular
spaces into two, three, four, or more portions, longitudinally.
The inner cylinders or one of them have or has a number of perforations, for
permitting the rising air from the flue to gain access to the annular spaces between
the cylinders.
Openings are also made in the annular plate, below the cylinders, to admit
currents of external air, or to permit the exit of the foul air.
The inner and outer cylinders are stayed and strengthened, where necessary, to
impart the necessary firniness thereto.
cover,
and
The cylinders are finished above with an ornamental or other suitable
the external cylinder has openings under this cover to permit the exit of foul air.
The arrangement of the concentric cylinders, and the number and sizes of the
perforations, as well as other minor details of construction may be very much
varied, to suit the character and purposes of the flues to which they may be
applied.
And in order that my said invention may be particularly described and ascertained,
reference is hereby made to the accompanying drawings, in which similar letters
of reference indicate corresponding parts.
Fig. 1 is an external elevation; Fig. 2 is a section, on the line a b; Fig. 3 is a
section on the line cd; Fig. 4 is an elevation, partly in section; and Fig. 5 is a
sectional elevation, on the line ef, with the plates h removed.
g is an inner cylinder, the lower end being conical. This cylinder is fitted with
four (more or less) vertical plates h, which divide the cylinder i into four parts.
The upper part of this cylinder (2) is perforated with a number of small holes to
permit the ascending air to pass into the annular chamber k. This chamber is
surrounded by the outer cylinder m, which has perforations n just under the eaves
of the cap or cover o. PPPP are four radial plates fitted above the cylinder i.
9999 are four gussets fitted in an inclined position. 8888 are four slots formed
in the annular plate . t is the pipe fitted to and sustaining the cowl. This
pipe t is made of a suitable size to fit the flue to which the cowl is to be applied.

page_text: The air ascending by the flue t enters the cylinder i, as shewn by the arrows.
From this cylinder the air passes, through the perforations made therein, to the
annular space. From this chamber the air can pass outwards, either through
the perforations n n, in an upward direction, or downwards through the slots 8;
either of the sources of outlet n or s, or both at the same time affording ample
means of escape for the vitiated air. Four small vertical tubes wwww are fitted
to the annular plate to admit cold air to the inside of the cylinder i to expel the
heated vapours, and four holes xxxx are also provided in the annular plate to
allow condensed water to pass over.
The whole of the upper part may be made detachable from the plate r, by means
of bayonet joints or other well known means, and the several parts of the
apparatus may be made to open, for purposes of cleansing and repairs.
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: -
1. The manufacture and use of cowls or caps, consisting of concentric cylinders,
with perforations and other openings, arranged and operating substantially as
herein before described, and shewn on the drawings.
2. In the construction of cowls and caps as aforesaid, the application and use of
the central cylinder g, pointed at the lower end, and the radial plates h, sub-
stantially as herein before described and shewn on the drawings.
3. In the construction of cowls and caps as aforesaid, the application and use of
the radial plates p, substantially as herein before described and shewn on the
drawings.
4. In the construction of cowls and caps as aforesaid, the application and use of
the cylinder i, fitted perforated and operating substantially as herein before
described and shewn on the drawings.
5. In the construction of cowls and caps as aforesaid, the application and use of
the openings s in the plate 7, substantially as herein before described and shewn
on the drawings.
6. The general construction, combination and arrangement of the several and
respective parts, together forming my improvements in cowls or caps for preventing
downdraught in ventilating shafts, flues and other analogous constructions, sub-
stantially as herein before described and shewn on the drawings.
Dated 12th November 1886.
GEO. DOWNING,
Agent for Applicant.