Year: 1897

page_text: I, THOMAS GELDART, of 54, West Street, Oldham, in the County of Lancaster,
Sheet Metal Worker, do hereby declare the nature of this invention to be as
follows:-
This invention relates to the construction of an improved chimney-top designed
to prevent down-draught in domestic and other chimneys.
The top of the chimney shaft itself is made of the usual shape being rectangular
at the bottom where it is provided with a flange for convenience of fixing onto
the chimney and tapering, upwards to a cylindrical mouth of (say) about nine
inches.
In this mouth I fit my improved chimney top the inner and lower part of
which consists of a cylindrical tube (preferably made of metal) fitting over the
cylindrical mouth and forming a continuation or prolongation thereof upwards
for about one foot (more or less according to requirements).
Round this cylindrical prolongation I fix a screen leaving a space of about
three or four inches, or more, all round it and the inner cylinder, and extending
upwards about a foot or more above the top or mouth of the inner cylinder. This
screen I prefer to make of a hexagonal form (but in some cases it may be
octagonal or even cylindrical), and to attach it to near the bottom of the cylin-
drical part, and for this purpose I taper the lower part of each side to a point or
nearly so, I then bend these points inwards and rivet or otherwise firmly fix each
of these points to the cylinder, thus leaving six triangular openings (at or near
the bottom) into the space between the cylinder and the screen.
The top part of each side of the screen is also tapered to a point or nearly
so, and is curved or bent outwards..
Inside this screen, about three inches or so above the top or mouth of the inner
cylinder, I mount or fix a disc or baffle plate larger than the mouth of the
cylinder but smaller than the inside of the screen so as to leave a space all round.
On the top of this I place four triangular vanes with their bases meeting in
the centre and their outer angles tapered off to a point at the edge of the disc.
If a wind or draught of air meets this screen horizontally or nearly so it will
cause either an upward or downward draught in the screen, either of which will
by suction cause an upward draught only in the central tube and chimney. And
f a downward blast should strike on the top, the disc or baffle plate above men-
ioned will prevent it from entering the inner tube throwing it round the inside
of the screen and causing it to pass downwards and escape at the lower triangular
penings, thus in any case not only preventing down draught in the inner tube-
ut by suction inducing an upward draught at all times in the inner tube and
himinév.

page_text: The disc or baffle plate may be so mounted that it can be removed when required
for cleaning purposes or otherwise.
Dated this 24th day of September 1897.
GEO. DAVIES & SON,
Agents for the Applicant, 4, St. Ann's, Square, Manchester.
I, THOMAS GELDART, of 54, West Street, Oldham, in the County of Lancaster,
Sheet Metal Worker, 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:.
-
This invention, relates to the construction of an improved chimney-top designed
to prevent down-draught in domestic and other chimneys.
The nature of my said invention and the manner in which the same is to be
performed or carried into practical effect will be readily understood on reference
to the sheet of drawings hereunto annexed and the following explanation thereof.
Fig. 1 on the drawings is an elevation, and Fig. 2 a vertical section of a
chimney-top-made according to my said invention and Figs. 3 and 4 are respec-
tively vertical section and plan views of a slight modification thereof.
The top a of the chimney-shaft itself is made of the usual shape being rectan-
gular at the bottom where it is provided with a flange a for convenience of
fixing onto the chimney, and tapering upwards to a cylindrical mouth of (say)
about nine inches in diameter.
On this mouth I fit my improved chimney-top the inner and lower part of
which consists of a cylindrical tube b, preferably made of metal, fitting over the
cylindrical mouth and forming a continuation or prolongation thereof upwards
for about one foot (more or less according to requirements).
Round this cylindrical prolongation I fix a screen c leaving a space of about
three or four inches, or more, all round between it and the inner cylinder b, and
extending upwards about a foot or more above the top or mouth of the inner
cylinder b. This screen I prefer to make of a hexagonal form, as shewn (but in
some cases it may be octagonal or even cylindrical) and to attach it to near the
bottom of the cylindrical part b, and for this purpose I taper or curve the lower
part of each side to a point or nearly so (see Fig. 1) I then bend these points
inwards and I rivet, or otherwise firmly fix each of these points to the cylinder b
thus leaving six openings (at or near the bottom) into the space between the
cylinder and the screen e.
The top part of each side of the screen is also tapered to a point, or nearly so,
and is curved or bent upwards as shown.
Inside this screen c about three inches or so above the top or mouth of the
inner cylinder b, I mount or fix a disc or baffle-plate d (see also plan view,
detached, Fig. 2) larger than the mouth of the inner cylinder 6 but smaller than
the inside of the screen c so as to leave a space all round.
On the top of this disc I place four triangular vanes with their bases meeting
in the centre and their outer angles tapered off to a point at the edge of the
disc i.
If a wind or draught of air meets this screen c horizontally, or nearly so, it
will cause either an upward or downward draught through the screen, either of
which will by suction cause an upward draught in the central 'tube 6 and the
chimney; and if a downward blast should strike on the top, the disc or baffle-

page_text: plate d above mentioned will prevent it from entering the inner tube, throwing
it round the inside of the screen c and causing it to pass downwards and escape
through the openings between the points c*, thus in any case not only preventing
down-draught in the inner tube b but by suction inducing an upward draught
at all times in the inner tube 6 and the chimney.
I prefer so to mount the disc or baffle-plate d (see Figs. 2 and 2) that it can
be removed for cleaning purposes or otherwise.
For chimneys in very windy situations I sometimes find it advantageous to
supplement the action of the baffle-plate d by the addition of tubes e as shown
at Figs. 3 and 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:-
-
"
The improved chimney-top for preventing down draught constructed and
arranged substantially as hereinbefore described and illustrated by the drawings
annexed.
GEO. DAVIES & SON,
Agents for the Applicant, 4, St. Ann's Square, Manchester.