Improvements in Ventilators and Chimney Cowls.
Year: 1892

page_text: COMPLETE SPECIFICATION.
Improvements in Ventilators and Chimney Cowls.
We ROBERT RENTON GIBBS of Saint James' Works, Mill Street, Liverpool,
Heating Engineer, and EDWIN HENRY MADDOCK of the same address, Heating
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 has for its object improvements in ventilators and chimney cowls.
Our improved ventilators are of two kinds, one for admitting and the other for
extracting air; in the former our improvements consist in enlarging the mouth or
outlet of an ordinary "Tobin" tube, and in the expanded part thus formed fitting
a loose tray made up of one or more tubes of perforated zinc or other suitable
material; the tube or tubes may be round, square or other section, the object being
to so increase the surface that whilst admitting the full quantity of air, instead of
it entering all in one body, to cut it up into a number of small columns of air with
the object of avoiding draught. If the air enters a room all in one body it blackens
the wall and ceiling, but when entering in minute columns as we propose, it is free
from this defect. The tubes will afford convenient receptacles for medicated or
perfumed wool; for disinfecting or perfuming the atmosphere.
The second and most important part of our invention is for certain improvements
in wind ventilators for extracting air or gases from buildings, ships, soil pipes and
chimneys &c., and consists in arranging in the head of the ventilator a series of
tubes having a longitudinal slit or slits or equivalent perforations opening inwards
towards the centre and towards each other, one end of each tube being stopped and
the other end opening into a chamber communicating with the extracting shaft.
In the central space to which all the slit openings converge, we form a core or
pillar, of such shape and size that its exterior surfaces form narrow passages past
the slit openings. In some cases we construct a reverse arrangement with the
slitted tubes opening outwards, and instead of a central core, we employ deflecting
plates leaving only a narrow passage for the wind past the slit openings; these
plates form the exterior of the ventilator. The wind blowing through the narrow
passages is gradually compressed until it reaches their narrowest part, and the part
where the slits are; from this point the passages widen out again and the vacuum
caused by the expanding wind creates a strong suction from the slitted tubes and
consequently from the extracting shaft.
As a single tube ventilator for a ridge or other position, we employ one or more
slitted tubes in a horizontal or other position, with deflecting plate or plates fixed,
opposite to the slits in the tubes in the same manner as before described.
In order that our said invention may be most fully understood and readily carried
into effect we will proceed to describe the drawings hereunto annexed.
Figs. 1 and 2 are side elevations, and
Fig. 3 is a front elevation, and
Fig. 4 a plan of an inlet ventilator constructed according to our invention.
a, a, a, is an ordinary "Tobin tube having its upper part b, b, b, expanded.
c, c, c, is a tray formed of one or more tubes, which may be loose or fastened
together as may be most convenient. We prefer to make these tubes of perforated

page_text: zinc, but they may be made of any suitable material which is perforated. These
tubes singly or combined can be lifted out to introduce medicated or perfumed wool,
and for this purpose one end of each tube is left open. The course of the air will
be understood by the direction of the arrows.
d, d, d, is the valve for closing the ventilator and for regulating the admission of
air; and as a simple means of indicating, at all times, the position of the valve
without having to examine it, we prolong the end of the valve spindle and mark on
it the words " open " and "shut," which when either one or the other is opposite
to a small arrow marked upon the body of the ventilator, will show at a glance the
position of the valve.
Figs. A, B, C, D, D¹, are sections and
Figs. E, F, are elevations of an extracting ventilator constructed according to
our invention.
a', a', is the chamber of the ventilator communicating with the extracting
shaft a².
b¹, 61, b¹, b¹, b', 6', ', are slitted suction tubes, stopped at one end and communi-
cating at the other with the chamber and extracting shaft. These tubes may be
round, square or other section, and the slits or perforations should be of such
dimensions that the combined area of one half their number shall equal the area of
the extracting shaft.
cl; c, c', c¹, c, c¹, is the central core or pillar which internally does not communi-
cate with the ventilator, only the exterior surfaces being made use of in such way
as to form narrow passages for the wind at right angles to the slits in the tubes.
d', d', d', d', d', are the wind passages, which should be the same width as the
slits e', e', e, e¹, e, in the tubes, and it is preferable that the faces opposite to the
slits should be slightly c
.concave.
Figs. G, G, H, K, are sections, and
Figs. G, H, K, are elevations of single tube ventilators, constructed according to
our invention.
a², a, a, a, a, a, a, is a slitted tube or tubes fixed on the ridge of a roof or
elsewhere and communicating with the interior of the building by one or more
tubes 63, 6, 6, 62, 62, 62, which are made to project inside the slitted tube or tubes a
short distance to prevent any rain or water entering them; any stray water which
may have entered through the slit finding an escape by the small holes c, c², c², c², c².
It will be noticed that in Figs. G, G¹, G³, the slitted tubes have their slitted
. side upward and in Figs. H, H₁, they are downward, the action being the same in
either case.
We are aware that cores, pillars or deflectors presenting flat or curved
surfaces towards the outlets or openings of the suction tubes have been
previously used, and we lay no general claim thereto but, having now particularly
described and ascertained the nature of our said invention and in what manner
the same is to be performed, we declare that what we claim is,
1. The construction of inlet tubes having expanded heads, fitted with hollow
trays formed of tubes of perforated material substantially as herein described.
2. The special forms of exhaust ventilators and cowls, having longitudinally
slitted or perforated suction tubes facing concave surfaces arranged substantially
as herein described and illustrated in Figures A, B, C, D, D', K and K'.
3. The use for ventilating purposes of a horizontal suction tube having a
longitudinal slit or series of perforations in conjunction with a deflecting plate fixed
opposite thereto substantially as described and illustrated upon Sheet 3 of the
accompanying drawings.
Dated this 9th day of April 1892
ROBERT RENTON GIBBS.
EDWIN HENRY MADDOCK.