A NEW OR IMPROVED CHIMNEY TOP AND VENTILATOR
Year: 1884

page_text: I RICHARD GERVASE KIRTON of Mistley in the County of Essex Brick and Tile
Manufacturer do hereby declare the nature of my said Invention for "A NEW OR
IMPROVED CHIMNEY TOP AND VENTILATOR " and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement
My Invention has for its object the construction of a new or improved chimney
top or ventilator, whereby the currents of external air acting upon the said top or
ventilator may produce an up-draught, and thereby counteract the usual tendency
of such currents to produce a down-draught Also that rain or hail may be
prevented by the same apparatus from entering the chimney or ventilating shaft or
the building. And further that the chimney top or ventilator may be so made that
when used as a chimney pot the sweep's brush can be pushed out at the top of the
chimney, so as to effectually clear it of soot without injury to the said top.
And my Invention consists in the construction of a top to be applied to the
chimney or ventilating shaft or aperture as the case may be in the following
manner. First I mould or shape a tube or passage (either circular square or of
other form in cross section) terminating at the top in a mushroom-shaped head a
small mouth or opening in the same communicating with the said tube. Upon the
sides of this tube and under the mushroom-shaped head I make wings or projections
of a suitable form being wider at their upper ends so as to fit against the interior
of the chimney pot or ventilating shaft or aperture, and at or to the bottom of
these wings or projections is formed or fixed a small cup to receive the downward
currents of air and by reflection to cause an up-draught-In some cases these
wings may be dispensed with and the cup supported by rods or bars as hereinafter
described.
By this arrangement of the top, the side currents of air pass round the under
side of the mushroom-shaped head, and out at the other side of the same, thereby
inducing an up-draught by suction. The wings or projections (when they are
used) are always below the rim at the top of the pot or ventilating shaft or
aperture.
•
In order to allow the sweep's brush to be pushed out at the top of my improved
chimney pot, rods are fixed to the above named wings or projections so as to act as
guides by passing through eyes fitted as required within the pot.
By this arrange-
ment the said top may be raised from the chimney pot for some distance (limited
by the length of the rods with stops at their lower ends to prevent them from
passing too far through the eyes) the said top will then by its own weight return
to its required position.

page_text: When the apparatus is used simply as a ventilator it would generally be made of
metal and of larger.dimensions than when used as a chimney pot, and would be
applied to a suitable air-shaft or aperture. In this case also a small tube may be
inserted in the lower part of the said cup in order to carry away any excessive
quantity of rain.
In order that my invention may be fully understood and readily carried into
effect I will proceed to describe it more particularly by the aid of the accompanying
drawings, in which is represented the improved chimney top or ventilator as formed
or constructed in earthenware and in metal.
DESCRIPTION OF THE DRAWINGS.
Fig: 1is a vertical section showing an earthenware chimney pot with the
improved top or ventilator applied thereto.
Fig 2 is a horizontal section in the line 1. 2 of Fig: 1.
Fig: 3 is a vertical section shewing the top and pot as formed of metal; and
Fig 4 shows a top and cup supported by rods or bars instead of by wings.
In these several figures the same letters of reference indicate corresponding
parts.
A is the chimney pot of the ordinary shape, B is the improved top or ventilator
which is inserted in the chimney pot as shewn. The top B has a mushroom-shaped
head C in the centre of which is a mouth and tube or passage leading downwards
to a cup D at the bottom, E E are wings or projections formed or fixed at or to the
outside of the said tube, which it. will be seen are adapted to fit against the interior
of the chimney pot or ventilating shaft or aperture, F F are the rods for guiding
the top B in its vertical ascent and descent as required when the chimney is swept.
These rods are passed through eyes G. G. fixed inside the chimney.
In Fig 4 is represented a top B in which the wings E E are dispensed with and
the bars or rods FF continued as shewn and branched so as to support both the
top B and the cup,D, collars or stops being fixed on the rods or bars F F at f. f. for
the same purpose.
On reference to the figures it will be seen that a downward current of air
entering at the head C will be caused to pass down the tube descending therefrom,
and by impinging on the concave surface of the cup D. will be reflected so as to
cause an up-draught within the chimney or ventilating shaft or aperture.
It will
also be seen that owing to the particular form of the head C all side currents of air
will be caused to pass round the underside of the said head C and out at the other
side of its diameter, thereby producing an up-draught by suction.
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
Iclaim is:-
The improved chimney pot or ventilator constructed in pottery or other suitable
material or in metal adapted and applied to a chimney pot or ventilating shaft or
aperture and with parts in combination whereby a down-draught is prevented
and an up-draught produced substantially as and for the purpose or purposes
described.
Dated this fourteenth day of October One thousand eight hundred and eighty