Improvements in Chimney or Ventilating Shaft Tops.
Year: 1893

page_text: Date of Application, 22nd Feb., 1893
Complete Specification Left, 5th Aug., 1893-Accepted, 9th Sept., 1893
PROVISIONAL SPECIFICATION.
Improvements in Chimney or Ventilating Shaft Tops.
SAMUEL JACKSON DIXON 16 Fern Street Coppice Oldham Lancashire Boiler
Inspector do hereby declare the nature of this invention to be as follows :—
My invention has reference to the construction of chimneys and chimney tops,
for prevention of down draughts and for assisting the up draught, and also to the
construction of ventilators and in connection therewith and consists of an inner and
an outer flue over the top of the outer flue is fixed a cowl which prevents down
draughts.
I intend to make the invention with or without a cowl on the top of the inner
Alue as occasion may require.
The manner of carrying the invention into practical effect is as follows-
When there is no down current of air to create a downdraught the air passes
down the outer to the inner flue assisting the up draught in the inner flue, and when
there is a down current of air it impinges on the cowl over the top of the outer flue
creating an up current in the outer flue which then carries away the gases and
products of combustion effectually preventing down draught.
The invention may be made of any convenient shape and of any materials
suitable and convenient for its construction-and may be made in separate parts and
if so desired of different material.
Dated this 21st day of February 1893.
SAMUEL JACKSON DIXON.
COMPLETE SPECIFICATION.
Improvements in Chimney or Ventilating Shaft Tops.
I, SAMUEL JACKSON DIXON, of 16 Fern Street, Coppice, Oldham, in the
County of Lancaster, Boiler Inspector, 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 tops for chimneys and ventilating shafts and is designed
to prevent down draughts and assist or promote a better up draught.
It consists essentially in constructing the chimney top or ventilator with two or
more flues or passages each open to the atmosphere at one end only, one of which
is protected with a hood or cover so placed as to deflect-any current of air striking
it in a downward direction and cause a suction or upward current therein which
will relieve any pressure or downdraught in the other and draw off the gases rising
in the flue or shaft as well as any current of air entering through the other passage
which has a free course through it both passages being preferably equal in area to
the flue or shaft to which the cowl is affixed.
It will be fully described with reference to the accompanying drawings in which
as examples two or three forms of chimney or ventilating shaft tops are shown.
Fig. 1, elevation of form 1 prefer.
Fig. 2, sectional elevation of same.
Fig. 3, sectional plan.
Fig. 4, sectional elevation of a modified form of the invention.
Fig. 5, sectional elevation of another modification.
Referring to Figs. 1 to 3 the second flue or passage A is placed concentrically
around the other one 13 the outer one being formed of the casing C and the inner
one by the casing D. The top ends only of both flues or passages are open to the
I Price Rd

page_text: atmosphere, the lower end of both opening into the flue or shaft to which the top is
affixed. Over the outer passage A is placed a curved deflecting top or hood E
any current of air striking which is deflected outwards and downwards past the
orifice a promoting an upward current in the passage A. When used for a
ventilator a top or cover of any suitable form may be placed over the inner
passage B to prevent rain falling down therein.
Referring to Fig. 4 the second flue or passage A is placed alongside the other
one B the two being divided by a longitudinal plate or diaphragm b. The upper
ends of both passages communicate with the external atmosphere and the lower
ends with the flue or shaft. The passage A is covered by a deflecting top or
cowl E which deflects any current of air striking it downwards and outwards past
the orifice a thereby promoting an upward current in A and relieving any pressure
caused in the flue by a downward current in the passage B.
Referring to Fig. 5, the second flue or passage A is constructed of an additional
pipe or tube branching out from the side of the other passage B. As in the
examples shown in the other figs. both passages communicate with the external
atmosphere only at their top ends and with the flue or shaft at their lower ends.
The passage A is covered with a deflecting top or cowl E which deflects downwards
and outwards past the aperture a any current of air striking it, thus promoting an
upward current in the passage A and relieving any pressure caused in the flue by a
down current in the other passage B.
The invention may be applied in other forms and to tops of either circular,
square, oblong or other convenient contour, and may be made as part of a building
or preferably separately and fixed thereon; and further the two flues may be made
of different shape or material attached together.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. A top for chimney-flue or ventilating-shaft constructed with two (or more)
passages the upper ends of both only open to the external atmosphere and the
lower ends open to the flue or shaft one of the passages being covered with a hood
or cowl to deflect any current striking it and promote an upward current therein to
relieve the pressure caused in the flue by any downward current in the other
passage and carry off all the gases and any air forced down the other passage
substantially as described.
2. A top for chimney-flue or ventilating-shaft having the several parts constructed
and arranged in combination substantially as and for the purposes described and
shown with reference either to Figs. 1 to 3, Fig. 4, or Fig. 5 of the drawings.
Dated this 3rd day of August 1893.
WM. P. THOMPSON & Co.,
6, Bank Street, Manchester, Patent Agents.