IMPROVEMENTS IN SUCTION COWLS FOR VENTILATING TUBES, SHAFTS, OR CHILINEYS
Year: 1875

page_text: LETTERS PATENT to Walter Charles Church, of No. 8, Victoria
Chambers, Victoria Street, Westminster, in the County of Middle-
sex, for the Invention of "IMPROVEMENTS IN SUCTION COWLS FOR
VENTILATING TUBES, SHAFTS, OR CHILINEYS."
PROVISIONAL SPECIFICATION left by the said Walter Charles Church
at the Office of the Commissioners of Patents, with his Petition,
on the 8th April 1875.
I, WALTER CHARLES CHURCH, of No. 8, Victoria Chambers, Victoria
Street, Westminster, in the County of Middlesex, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN SUCTION COWLS FOR
VENTILATING TUBES, SHAFTS, OR CHIMNEYS,” to be as follows:-
My Invention relates to cowls placed upon tubes, shafts, or chimneys,
for the purpose of causing a draught to be created either by wind when
the cowl is stationary, or by-its passage-through-the air when it is on a
locomotive carriage or vessel, the chief object of my Invention being to

page_text: secure an up draught, and to prevent down draught by causing such
currents as would ordinarily produce down draught to act in producing
an up draught.
I construct my improved cowls in two forms, one which is fixed, and
the other which is mounted on an axis so as to turn as a vanc, presenting
always one face to the air current, and these two forms may be used
either separately or in combination.
I will first describe the fixed cowl which is of the following
character:-I expand the mouth of the tube or chimney and insert into
the mouth the apex of an inverted cone, so that the outlet from the tube
is the annular space between the said cone and the lip of the tube.
Outside this lip I fix a frustrum of a conc and over it another frustrum,
leaving between the two a space which I divide by a number of vertical
radiating partitions or webs, and I surround the whole by a cylindrical
or slightly coned shell. When a current of air impinges on any side of
this cowl it is deflected upwards between the two outer conical frustra,
and caused to pass across the annular outlet from the tube, creating a
draught therein by its lateral action. Should there be a current down-
wards, such as would tend to create a down draught, this current being
arrested by the base of the inverted cone and also being turned
downwards through the space between the outer conical frustrum
and the casing, is caused to pass the outlet of the tube and to create a
draught therein by its lateral action.
My improved cowl of the vane kind is mounted so as to turn freely
with suitable loose packing on the top of the tube or chimney, and
provided with wings on its back part so as to cause its front to be
presented towards the wind or air current. The body of the cowl is of
cylindrical or slightly conical form, communicating at the side with the
tube or chimney. Within this body I fix a conical tube open in front to
receive the air current, and another cone in an inverted position at the
back, the apex of this cone entering some distance into the smaller
mouth of the conical tube, so that the outlet of the latter is made of
annular form somewhat behind the lateral opening from the tube or
chimney. Outside the body of the cowl I fix another conical tube with
its larger mouth towards the front. A current setting against the front
of the cowl enters the internal conical tube, and also the annular space
surrounding the body of the cowl, and thus two annular currents are
made to flow through the back mouth of the cowl, the one inside and

page_text: ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Walter Charles Church, do hereby
declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained in
and by the following statement thereof, reference being had to the
accompanying Sheets of Drawings and to the figures and letters marked
thereon, that is to say :-
My Invention relates to cowls placed upon tubes, shafts, or chimneys,
for the purpose of causing a draught to be created either by wind when
the cowl is stationary, or by its passage through the air when it is on a
locomotive carriage or vessel, the chief object of my Invention being to
secure an up draught and to prevent down draught, by causing such
currents as would ordinarily produce down draught to act in producing
an up draught.
I construct my improved cowls in two forms, one which is fixed, and
the other which is mounted on an axis so as to turn as a vane presenting
always one face to the air current, and these two forms may be used
either separately or in combination.
I will first, describe the fixed cowl which is of the following
character:-I expand the mouth of the tube or chimney and insert into
the mouth the apex of an inverted cone, so that the outlet from the tube
is the annular space between the said cone and the lip of the tube.
Outside this lip I fix a frustum of a cone and over it another frustum,
leaving between the two a space which I divide by a number of vertical
radiating partitions or webs, and I surround the whole by a cylindrical
or slightly coned shell. When a current of air impinges on any side of
the cowl it is deflected upwards between the two outer conical frusta, &
and caused to pass across the annular outlet from the tube, creating a
draught therein by its lateral action. Should there be a current down-
wards such as would tend to create a down draught, this current being
arrested by the base of the inverted cone, and also being turned
downwards through the space between the outer conical frustum and the 3
casing is caused to pass the outlet of the tube and to create a draught
therein by its lateral action.

page_text: the other outside of the air in the body of the cowl causing by lateral
action a draught from the tube or chimney. By extending the inverted
cone backwards and also the outer conical tube so as to overlap it, a
contrary or baffling current is turned asido and so prevented from
creating down draught.
In forming the cowls described above I so proportion the parts as to
presont suitable areas at the several inlets and outlets. The two cowls
which I have described may be used in combination, the vane cowl
being made with a mouth turned upwards, and the cowl first described
being placed upon the said mouth. Or a portion of the first described
cowl may be applied to the mouth of the vane cowl to arrest and deflect
contrary currents.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Walter Charles Church in tho Great Seal Patent
Office on the 7th October 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WALTER
CHARLES CHURCH, of No. 8, Victoria Chambers, Victoria Street, West-
minster, in the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighth day of April, in the year of
our Lord One thousand cight hundred and seventy-five, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Walter Charles Church, Her special
license that I, the said Walter Charles Church, my executors, adminis-
trators, and assigns, or such others as I, the said Walter Charles Church,
my executors, administrators, and assigns, should at any time agree with,
and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN SUCTION COWLS FOR VENTILATING TUBES, SHAFTS, OR CHIMNEYS," upon the
condition (amongst others) that I, the said Walter Charles Church, my
executors or administrators, by an instrument in writing under my, or
their, or one of their hands and scals, should particularly describe and

page_text: the inner partitions E. I prefer to fix on the outside of the frustum C an
outer deflecting frustum H, so that a current of air flowing up the space
between C and D is prevented from blowing directly against the upper
mouth of C, and is directed towards the passage round the upper lip of
the inverted cone B. From this construction it will be seen that when a
wind or current plays against any side of the cowl, it is directed upwards
along the passage between the frusta C and D, and causes by its lateral
action a current out at the upper mouth of the frustum C, thus drawing
from the pipe A. Or again should a current of air set downwards it is
prevented by the inverted cone B from blowing down the pipe A, and it is 1
directed down the space between C and D, drawing air by lateral action
from the upper mouth of C, and in this case the current setting down
the space between D and F aids the down current between O and D.
Fig. 3 represents a vertical section of a revolving or vano cowl con-
structed according to my Invention; Fig. 4 is a plan of the upper flango ]
of the revolving sleeve pipe to which it is fixed.
Fig. 5 is a plan looking from below of the lower end of the ventilating
pipe on which the cowl is mounted.
Fig. 6 represents on its right-hand side a half front elevation, and on
its left-hand side a half back elevation of the cowl. The sleeve pipe I is 2
mounted so that it can turn freely on a central pivot, and it extends
downwards outside the upper part of the ventilating pipe J, where its
lip bears lightly on a band of suitable packing i held in a groove of the
pipe. Setting screws ; entering another groove prevent the cowl from
rising. In the body of the cowl is a pipe K which might be cylindrical 2
but is preferably coned a little, as shewn in Fig. 3, and within this pipe
is a coned pipe L so arranged as to leave between it and the pipe K an
annular space, closed in front, and open at the back, into which space
there is a free lateral opening from the sleeve pipe I. A cone M is
fixed with its apex towards the front, entering the inner pipe L, and the 3
whole is enclosed in a coned pipe N, and at the back by a conical
frustum shell O, radial diaphragms m, n, and o, being introduced where
necessary to support the one shell from the other with the required
annular spaces between them. The large shell O at the back part of the
cowl acts as a vane, causing the cowl to present its opposite side or front 3
to the wind or air current, which entering the open passages therein,
that is to say, within L and between K and N produces two annular

page_text: currents between M and N, which have the effect of creating by their
inductive action a current between them from the space between K and
L, and consequently from the pipe I which communicates with that
space. The current also passing between N and O aids the flow from
between M and N. Should the cowl be purposely or accidentally fixed
so that the wind or air current might blow against its back, the cone M
and the arrangement of the passages around and, beyond it, not only
prevent the production of a down draught in the pipe I, but they even
encourage to a small extent an up draught therein.
Having thus described the nature of my Invention and in what
manner the same is to be performed I claim,-
-
First. The use for ventilating tubes, shafts, or chimneys of a fixed
cowl constructed substantially as herein described with reference to
Figs. 1 and 2 of the accompanying Drawings, the said cowl consisting of
a combination of conical shells with annular passages between them
divided by radial partitions, in such manner that currents of air setting
in any direction are deflected by these shells and partitions, so as to
create by inductive action an up draught in the pipe to which the cowl
is applied.
Second. The use for ventilating tubes, shafts, or chimneys of a
revolving or vane cowl constructed substantially as herein described with
reference to Figs. 3, 4, 5, and 6, of the accompanying Drawings, being a
combination of conical shells with passages so arranged that currents of
air setting against the front of the cowl are guided so as to create by
inductive action an up draught in the pipe to which the cowl is
applied.
In witness whereof, I, the said Walter Charles Church, have here-
at my hand and pool this Si-th day of October in the wa
applied.
In witness whereof, I, the said Walter Charles Church, have here-
unto set my hand and seal, this Sixth day of October, in the year-
of our Lord One thousand eight hundred and seventy-five.