IMPROVEMENTS IN THE CONSTRUCTION OF VEN- TILATORS AND SMOKE COWLS
Year: 1879

page_text: LETTERS PATENT to Robert Munn, of Glasgow, in the County of Lanark, North
Britain, for the Invention of "IMPROVEMENTS IN THE CONSTRUCTION OF VEN-
TILATORS AND SMOKE COWLS."
Sealed the 26th September 1879, and dated the 12th July 1879.
PROVISIONAL SPECIFICATION left by the said Robert Munn at the Office of
the Commissioners of Patents on the 12th July 1879.
ROBERT MUNN, of Glasgow, in the County of Lanark, North Britain. "IMPROVE-
MENTS IN THE CONSTRUCTION OF VENTILATORS AND SMOKE COWLS."
This Invention, which relates to improvements in the construction of ventilators
and smoke cowls, has for its objects to render the same more efficient and certain in
working
Under one arrangement the Invention consists of an oblong trumpet shaped cowl,
preferably greater in width than in height, and open at both ends, and provided
with a vane, so that the narrow end of the cowl is kept to the wind. Within the
said cowl louvres are arranged in a horizontal position, the bottom edge of the said
louvres being turned up so as to form a trough, by means of which drift water is
caught and run off through holes at the sides of the cowl. The weight of the head
of the cowl is carried upon the top of a fixed spindle, which is held within the shaft
of the cowl, the bearing being upon a shield fixed to the top of the head, the said
shield being preferably a piece of glass. The aforesaid head is maintained in a true
vertical position by a cross-bracket having a journal working upon the spindle; this
journal is so suspended that it works within an oil cup which is supported within
the shaft. By this arrangement the head is capable of turning upon its spindle with
a minimum of friction.
Under a second modification of this Invention the cowl is preferably constructed
of greater height. The louvres are arranged in a vertical position in two rows
within the revolving head. In front of the said louvres at the narrow end of the
open head is fixed a wedge shaped divider to direct the current so as to cause an
exhausting effect in front of the louvres. The arrangement by means of which
the bead turns may be essentially similar to that described under the first
arrangement.

page_text: Under a third modification the cowl is a fixture, and is preferably square in form;
ports are formed in its sides, the said ports being protected by louvres, which are
fixed in a horizontal position; these louvres are projected in an angular form from
the sides of the cowl, thus diverting the outer current of air, which, impinging upon
the louvres in the direction of their angles, produces an exhaust from the aforesaid
ports. By virtue of this arrangement of louvres a current from above or below
will be equally effective,-and- at the same time the ingress of drift water is
prevented
The modifications described with references to this Invention are equally appli-
cable, whether used as ventilators, or for extracting foul air, or as cowls for
extracting products of combustion.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Robert Munn in the Great Seal Patent Office on the 12th January
1880.
ROBERT MUNN, of Glasgow, in the County of Lanark, North Britain.
MENTS IN THE CONSTRUCTION OF VENTILATORS AND SMOKE COWLS."
" IMPROVE-
My Invention relates to improvements in the construction of ventilators and
smoke cowls, and has for its objects to render the same more efficient and certain in
working.
Figure 1 of the accompanying Drawings represents in vertical section, Figure 2
in horizontal section, and Figure 3 in perspective a cowl or ventilator constructed
according to one arrangement of my Invention. The oblong trumpet shaped head A
or cowl proper (preferably greater in width than in height) is open at both ends,
and is provided with a vane B, so that the narrow end of the said head A is kept
to the wind. Within the cowl louvres a are arranged, extending horizontally from
side to side above the opening of the chimney or shaft, and inclining upwards in
the direction in which the wind passes through the cowl, as shewn in Figure 1. The
lower part of the said louvres is turned up to form troughs to receive drift water,
which is run off at holes c'through the cowl at the side. The weight of the head A
is carried upon the top of a fixed spindle d, the head being provided with a shield
or bearing surface b, preferably of glass, to bear upon the said spindle, which spindle
is held by a bracket e within the shaft of the cowl. Upon the cross bracket fin
the lower part of the head A is a bearing 2, through which the spindle d passes,
and by which the head is maintained in a vertical position. The said bearing is
situated and works in a cup e² (containing oil or other lubricant) upon the bracket e,
by the lubricant in which cup the bearing is lubricated. By this arrangement the
head A. turns upon the spindle d with but little friction.
Figure 4 represents in vertical section, Figure 5 in horizontal section, and Figure 6
in perspective a cowl or ventilator constructed according to another arrangement of
my Invention. In this arrangement the head A is preferably of greater height than
in the arrangement first described, and the louvres a are arranged in a vertical posi-
tion in two rows within the revolving head A on either side the opening of the
shaft or chimney, around which opening is preferably a rim or raised part to pre-
vent entrance of drift water. In front of the louvres is a wedge-shaped divider a²,
having its narrow edge presented to the mouth of the cowl, and its sides inclining
outwards in the direction in which the wind passes through the cowl, the louvres a
being inclined in like manner. The head A is supported upon a spindle, as
described with regard to the first arrangement, and is provided with a vane, which
causes its narrow end to be presented to the wind.
In the arrangements hereinbefore described the wind passing through the head
of the cowl in the direction of the arrows x produces an exhausting effect, so that
the smoke or foul air are drawn up and discharged from the shaft or chimney, as
indicated by the arrows y.
Figure 7 represents in vertical section, Figure 8 in horizontal section, and Figure 9
in perspective another arrangement of my Invention, in which the cowl or venti-
lator is a fixture, and may be square, hexagonal, or other figure. Ports or openings g
are formed in the sides of the cowl, and outside the said openings are arranged
series of louvres a in a horizontal position, the said series projecting in an angular
form from the sides of the cowl above and below the openings g in the sides, as
shewn in Figure 7, the louvres above being inclined downwards and outwards, and
those below being inclined downwards and inwards. Deflectors or covers a³ are
arranged above, and below, and outside the louvres a, as shewn in Figure 7, and a
wedge shaped deflector or covering strip at is situated in front of the series of
louvres. The outer current of air thus impinging upon the deflectors and louvres

page_text: passes between them, or impinges upon them, and is deflected by them, as shewn
by the arrows x (those on one side of Figure 7 shewing the direction of a down-
ward current, and those on the other side the direction of a side current), and
_ produces an exhaust-from-the-openings g, and draws the smoke or foul air from the
shaft or chimney. With this arrangement of cowl or ventilator a current from
above or below, or from either side, will be equally effective, and drift water does
not enter the shaft or chimney.
The several arrangements of my Invention herein before described are applicable
for use as ventilators or for extracting foul air, and as cowls for withdrawing pro--
ducts of combustion.
In
The arrangement, Figures 7, 8, and 9, is especially suited as a ventilator.
Figure 10 I have shewn a simplified and therefore cheaper arrangement, suited för
use as a smoke cowl, from which the louvres a are omitted, and the covering strips
and deflectors a³ and a are situated near to and extended over the opening g, as
shewn, so as to give the advantages described with regard to the arrangement,
Figures 7, 8, and 9.
Having now described and particularly ascertained the nature of my said Inven-
tion, and the system, mode, or manner in or under which the same is or may be
used or practically carried into effect, I would observe in conclusion that what I
consider to be novel and original, and therefore claim as the Invention secured to
me by the herein before in part recited Letters Patent is,-
First. The improvements in the construction of ventilators and smoke cowls with
revolving heads consisting in the employment in such revolving heads of louvres so
arranged above, at, or before the top of or point of exit for the foul air or smoke
from the shaft or chimney as that the wind or currents of air passing through the
said heads, or above or before the said louvres, produces the exhausting effect to
cause the withdrawal of the smoke or foul air, essentially as hereinbefore described
with reference to Figures 1 to 6 of the accompanying Drawings.
Second. The arrangement or construction of parts constituting the ventilator or
cowl, illustrated in and described with reference to Figures 1, 2, and 3 of the
accompanying Drawings.
Third. The arrangement or construction of parts constituting the ventilator or
cowl, illustrated in and described with reference to Figures 4, 5, and 6 of the
accompanying Drawings.
Fourth. The employment in cowls or ventilators of the bearing f2 and lubricant
cup e², described with reference to Figure 1 of the accompanying Drawings.
Fifth. The arrangement for catching and running off drift water, shewn in and
described with reference to Figure 1 of the accompanying Drawings.
Sixth. The arrangement or construction of parts constituting the ventilator or
cowl, described with reference to Figures 7, 8, and 9, and also that described with
regard to Figure 10 of the accompanying Drawings, that is to say, a stationary ven-
tilator or cowl wherein louvres and deflectors are arranged, essentially as illustrated
in the said Figures 7, 8, 9, and 10 of the accompanying Drawings, at such relative
angles or inclinations as to cause the effective action for withdrawing foul air or
smoke, of currents of air, passing between, through, or around them, whether from
above, from below, or from either side.
In witness whereof, I, the said Robert Munn, have hereunto set my hand and
seal, this Ninth day of January, in the year of our Lord One thousand
eight hundred and eighty.