IMPROVEMENTS IN AIR EXTRACTING APPARATUS
Year: 1883

page_text: LETTERS PATENT to Thomas Rowan, of Palace Chambers, in the city of
Westminster, Consulting Engineer for an Invention of "IMPROVEMENTS IN
AIR EXTRACTING APPARATUS "
PROVISIONAL SPECIFICATION left by the said Thomas Rowan at the Office
of the Commissioners of Patents on the 26th January 1883.
THOMAS ROWAN of Palace Chambers, in the city of Westminster, Consulting
Engineer "IMPROVEMENTS IN AIR EXTRACTING APPARATUS
"
This invention relates chiefly to further improvements on the apparatus for
ventilating railway carriages described in the specification of former Letters Patent
granted to ne N° 162, dated the thirteenth day of January one thousand eight
hundred and eighty one, the object of the present improvements being to provide
an air extractor for railway and other carriages, or for ships, or for ventilating
pipes, whereby the forward motion of the carriage or ship, or the natural action of
the wind will produce an induced current whereby the air from the interior of the
carriage or ship or otherwise will be extracted in a more simple and efficient
manner than hitherto.
In constructing an air extractor according to my present improvements I provide
an air ejecting shaft with air injectors similar to those described in the specification
of my said former Letters Patent but the upper part of the apparatus instead of
being in the same line as the injectors is placed at right angles thereto and may be
either single or double. To the nozzle of the injecting pipes I adapt a valve or
flap so balanced and arranged that when the current passes or is made to pass in
one direction the said valve or flap will close one outlet to the top of the apparatus
leaving the other free or open and when the current passes in the opposite direction
the valve or flap is reversed.
In a modification of the arrangement especially adapted for railway and other
carriages and ships, the ejection tube is made in the form of a syphon the shorter
leg of which may be divided and the longer leg of which opens into the carriage

page_text: and is provided with air injectors similar to those hereinbefore described. The
outer end or ends of the ejection tube is or are provided with suitable deflectors.
In another arrangement I provide the ejecting tube with a revolving head placed
inside the fixed head or top of the apparatus in such a manner that the air made
to pass (by the motion of the carriage or otherwise) through the fixed head is so
directed that an induced current is produced in the ejection tube. Or instead of
the revolving head I provide a balanced flap or valve whereby a similar effect is
produced
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Thomas Rowan in the Great Seal Patent Office on the 26th July
1883.
THOMAS ROWAN of Palace Chambers in the city of Westminster, Consulting
Engineer "IMPROVEMENTS IN AIR EXTRACTING APPARATUS
"
This invention relates chiefly to further improvements on the apparatus for
ventilating railway carriages described in the specification of former Letters Patent
granted to me N° 162, dated the thirteenth day of January one thousand eight
hundred and eighty one, the object of the present improvements being to provide
an air extractor for railway and other carriages, or for ships, or for ventilating
pipes whereby the forward motion of the carriage or ship, or the natural action of
the wind will produce an induced current whereby the air from the interior of the
carriage or ship or otherwise will be extracted in a more simple and efficient
manner than hitherto.
In constructing an air extractor according to my present improvements I provide
an air ejecting shaft with air injectors similar to those described in the specification
of my said former Letters Patent but the upper part of the apparatus instead of
being in the same line as the injectors is placed at right angles thereto and may be
either single or double. To the nozzle of the injecting pipes I adapt a valve or
flap so balanced and arranged that when the current passes or is made to pass in
one direction the said valve or flap will close one outlet to the top of the apparatus
leaving the other free or open and when the current passes in the opposite direction
the valve or flap is reversed.
In a modification of the arrangement especially adapted for railway and other
carriages and ships, the ejection tube is made in the form of a syphon with one or
more shorter legs and the longer leg opens into the carriage or chamber, and is
provided with air injectors similar to those herein before described. The outer end
or ends of the ejection tube is or are provided with suitable deflectors.
In another arrangement I provide the ejecting tube with a revolving head placed
inside the fixed head or top of the apparatus in such a manner that the air made
to pass (by the motion of the carriage or otherwise) through the fixed head is so
directed that an induced current is produced in the ejection tube. Or instead of

page_text: the revolving head I provide a balanced flap or valve whereby a similar effect is
produced.
In order to enable my invention to be fully understood I will proceed to
describe the same by reference to the accompanying drawing in which figure 1,
represents an elevation of an air extractor with the air injectors placed at right
angles to the upper part of the apparatus and constructed according to my
invention; figures 2 and 3, are elevations and figure 4, is a vertical section of my
syphon form of air extractor specially adapted for railway and other carriages and
ships; figure 5, is a vertical section of an air extractor provided with a revolving
head; figure 6 is a vertical section of an air extractor provided with a balanced.
flap or valve within the fixed head; figure 7, elevation and figure 8 vertical section
shewing a modification of the air extractor shewn in figures 2, 3 and 4, and figure 9
is an elevation and figure 10 a section shewing a further modification of the air
extractor shewn in figures 2, 3 and 4 and serving for a chimney top or cap.
Similar letters of reference in all the figures represent similar or corresponding
parts.
In the arrangement shewn in figure 1, is the air ejecting or abstracting shaft
and b, b, the air injectors similar to those described in the specification of my said
former Letters Patent; c, is the upper part of the apparatus which I now place at
right angles to the injectors b, b; d, is the balanced valve or flap which I adapt to
the nozzles of the injecting pipes b, b; by this arrangement whatever be the
direction of the current one of the outlets to the top of the apparatus will be
closed and the other will be open.
The operation will be understood without further description.
In the arrangement shewn in figures 2, 3 and 4, a, b, b, and d, represent similar
parts to those indicated by the same letters in figure 1, the abstracting tube a, in
this present arrangement being made in the form of a syphon as shewn; e, e, are
air deflectors on the outer end of the shorter leg of the abstracting tube; an
annular space f, (figure 4) being left between the deflectors or louvres e, and the
outside of the shorter leg of the syphon abstracting tube; the currents of air
striking against the abstracting tube a, will be deflected downwards by the
louvres e, and will thereby produce an upward current in the abstracting tube a;
it will be obvious that the syphon may be formed with more than one shorter leg
if found advantageous or convenient.
In the arrangement shewn in figure 5, I provide the abstracting tube a, with a
revolving head g, placed inside and revolving within the fixed head or upper part c,
of the apparatus. The air passing (by the motion of the carriage or otherwise)
through the fixed head c, will so direct the revolving head! g, that an induced
current will be produced in the abstracting tube a.
In the arrangement shewn in figure 6, I provide a balanced flap or valve d,
within the fixed head c, of the apparatus. When the carriage is in motion the
direction of the current will be determined by the direction in which the carriage
moves, and if the direction of the current of air through the fixed head c, be that
indicated by the arrow it will force the flap or valve d, before it into the position
shewn in the drawing and will cause an upward current in the abstracting shaft a.
If the direction of the current be reversed the flap d, will turn on its centre and
take the position shewn in dotted lines.
When it is intended to abstract air containing solid particles such as soot which
might interfere with the action of the balanced flap d, shewn in figures 1, 3 and 4
I dispense with this flap and with the air injectors b, b, the abstracting action being
caused solely by the deflection of the currents of air passing through the deflecting
louvres e.
Instead of the shorter leg of the syphon abstracting tube being curved over as
shewn in figures 2, 3, and 4, it may be formed straight, the louvres e, in this case
deflecting the air in an upward direction. This modification as adapted to a
chimney is shewn in figures 7 and 8, the wind striking the chimney a, in any

page_text: direction will enter the louvres e, and thence the annular space f, and passing out
at the top thereof will induce an upward current in the shaft or chimney a.
A similar result may be produced by placing the deflectors on top of the air
abstracting tube a, as shewn in figures 9 and 10 and placing a cap h, over the top
as shewn, this modification being most suitable to ships to prevent water getting
down the abstracting tube.
Having thus described my invention and the manner of performing the same I
wish it to be understood that what I claim is :-
The improved air extracting apparatuses constructed, arranged and operating
substantially as hereinbefore described and represented in the accompanying
drawing.
In Witness whereof I the said Thomas Rowan have hereto set my hand and
seal this twenty fifth day of July in the year of our Lord one thousand eight
hundred and eighty three.
MITANCLA DAN7137
THOMAS ROWAN (L.B.)