An Improved Ventilator or Air-extractor, chiefly designed for Use on Railway-carriages.
Year: 1894

page_text: Date of Application, 20th July, 1894-Accepted, 25th Aug., 1894
COMPLETE I MOLT
An Improved Ventilator or Air-extractor, chiefly designed for Use
on Railway-carriages.
I, LINDSLEY BYRON PETERS, of Moorgate Works, Moorfields, in the County
of London, Engineer, 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 an improved ventilator or air-extractor which is chiefly
designed for extracting or exhausting air from railway-carriages to ventilate the
same. My improved air-extractor is, however, also useful for the ventilation of
rooms or apartments, public buildings, factories and the like.
The object of the said invention is to provide a ventilator or air-extractor which
can be made at a comparatively low cost, and which, whatever may be the relative
direction of the external air-currents, will operate effectively to draw out the air
from the space to be ventilated, whilst entirely preventing the passage of rain into
the said space. My improved device, therefore, when applied to a railway-carriage,
does not require to be adjusted, but will operate equally well whether the carriage
is travelling in one direction or the other.
My improved ventilator or air-extractor is made with a hollow casting, cap or
hood. of spherical or other suitable shape, which encloses the upper end of a
ventilating tube or shaft, and which has an annular opening or slit or set of
This shield or
openings or slits, surrounded by an annular shield or deflector.
deflector is fixed in such a position as to leave a suitable annular space between the
same and the said opening or openings; the said shield or deflector is, moreover,
made of such width or height and is so arranged relatively to the said cap or hood
that it overlaps the said opening or openings at the top and bottom thereof.
The said ventilating tube or shaft extends into the said cap or hood to a
considerable distance above the bottom of the same, so that any rain entering the
aforesaid opening or openings will impinge against the exterior of the said tube or
shaft; and holes are formed in the bottom of the said cap or hood, close to the
said tube or shaft, to permit the egress of rain or moisture, so that the latter
cannot accumulate in the said cap or hood and overflow into the ventilating tube
or shaft.
In the accompanying drawing I have shown how my said invention may be
conveniently and advantageously carried into practice.
Figure 1 is a vertical central section,
Figure 2 a side elevation, and
Figure 3 a plan or top view of one form of my improved ventilator or air-
extractor.
Like letters indicate corresponding parts throughout the drawing.
a is the ventilating tube or shaft; 6 is the cap or hood enclosing the upper end
of the same.
This cap or hood as shown is formed of two hollow hemispherical
parts each of which is formed with an annular projection or flange b¹; and these
two parts are so situated relatively to each other that there is between the flanges
of the same an annular opening or slit e of dimensions proportionate to the amount
of ventilation required. The said cap or hood is preferably provided with an
ornamental top as shown. A ring or annular shield or deflector d surrounds the
opening or slit c. The internal diameter of this ring or deflector is so much greater
than the external diameter of the flanges 6 that there is an annular opening e of
suitable dimensions between the said ring and each of such flanges, the said ring
being attached to the flanges b' by supporting pieces or webs f. The said ring is,

page_text: moreover, of such width or height that it extends above and below the flanges b
and therefore overlaps the annular opening between the said flanges both at the top
and bottom thereof.
The tube a extends upward within the cap or hood b so that its upper end is
about on a level with the middle of the opening c; and holes g for the egress of
rain or moisture are formed in the lower part of the cap or hood close to the said
tube a.
This tube is, moreover, provided with a flange a whereby it may be
secured, by means of screws or other fastenings, to the roof of a railway-carriage
or of any other apartment or chamber to be ventilated.
When a current of air impinges against the ring or deflector d in any direction,
or when the ventilator is moved through the air in any direction, an exhaust current
is induced whereby the foul air is drawn from the carriage or chamber to be
ventilated, through the tube a and out through the openings c, e, this action being
assisted by the heat of the air in the top of the carriage or chamber; in this
manner a powerful upward current is established and the carriage or chamber is
efficiently ventilated. Any rain that may be blown into the cap or hood through
the openings e, c, will be intercepted by the part of the tube a within the said cap.
or hood, and, descending into the lower part of the said cap or hood, will escape
through the openings g.
It is evident that, by reason of the peculiar construction of my ventilator, even
if the cap or hood were made without the supplementary holes g, the rain or
moisture accumulating in the said cap or hood would overflow over the lower
flange b and therefore would not enter the tube or shaft a.
The ventilator or air-extractor shown in the drawing is cast in a single piece,
which is a very advantageous and economical way of making the same. The said
ventilator or air-extractor may, however, be made in two or more parts or pieces
joined together in any convenient manner.
I sometimes use in combination with my ventilator or air-extractor, a perforated
plate provided with an adjustable perforated cover or shutter, which is arranged
beneath the lower end of the ventilating tube or shaft for the purpose of regulating
or controlling the flow of air into the same.
It is evident that I can somewhat modify the shape and construction of the parts
of my apparatus without departing from the nature of my said invention; and
that the cap or hood and ring or deflector can be arranged in the manner above set
forth in combination with various kinds of ventilating tubes or shafts.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
First. A ventilator or air-extractor comprising a cap or hood which encloses
one end of a ventilating tube or shaft and which is provided with an annular
opening or set of openings surrounded by a ring or annular shield or deflector, with
or without one or more supplementary openings for the egress of rain or moisture,
substantially as, and for the purposes, hereinbefore described.
Second. The improved ventilator or air-extractor constructed substantially as
above described with reference to the accompanying drawing.
Dated the 20th day of Tul 1001
L. BYRON PETERS.
D. Young & Co.,
11 & 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.
L. BYRON PETERS.
D. Young & Co.,
11 & 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.