IMPROVEMENTS IN VENTILATORS
Year: 1874

page_text: PROVISIONAL SPECIFICATION left by John Hill and John Edwards Hey
at the Office of the Commissioners of Patents, with their Petition,
on the 11th December 1874.
WC, JOHN HILL and JOHN EDWARDS HEY, both of Halifax, in the
County of York, Ventilating Engineers, do hereby declare the nature of
the said Invention for " IMPROVEMENTS IN VENTILATORS," to be as follows:―
-
This Invention relates more particularly to that class of ventilator
known as Watson's syphon ventilator, in which a diaphram or diaphrams
are employed for separating the "shaft," and conical or other top part
or hood into two parts, one for the egress of foul air and the other for
admitting a supply of fresh pure air, but it is also applicable to "single
tube" ventilators.
The object of our improvements is to so construct the "cowl" or head
of the ventilator that down draft resulting from the force of wind acting
on the ventilator may be avoided or reduced to a minimum, and fresh air
regularly introduced without reducing the ventilating capacity of the
shaft of the ventilator, and dispensing with the use of a shield or
deflecting plate, suspended under the mouth of the ventilator below the

page_text: .
Our improvements are,-
Firstly. In ventilators which consist of a shaft with conical or other
hood and rim (divided as above stated by a diaphram), which hood and
rim are attached to the shaft by a series of stays, brackets, or midfeathers;
we effect our object by placing inside the said cone or hood another cone
divided internally by the diaphram of the hood and shaft. This
internal cone is placed sufficiently above the top of the shaft to allow of
a free passage of air in and out of the ventilator, and is supported by the
same stays, brackets, or midfeathers, which support and fix the outer
cone to the shaft, and in order that the wind may strike upwards only
on a limited surface of the ventilator shaft at one time we use a series
of stays, brackets, or midfeathers, which fasten the cowl or hood to the
shaft and carry the same up to the under edge of the inner conc, so as
to carry the force of the current of air sent up between these brackets or
midfeathers on and over the inner conc. A current of air striking
against, the shaft of ventilator, and upwards into the interior of the
outer cone instead of being transmitted or reflected therefrom to the
interior of the shaft, and so into the room or building, is thrown upon
the outer surface of the inner cone which may be made to any desired
angle, and thence in a direction which is opposed to the first motion of
the current passing outwards again by the inner surface of the rim of
the outer cone or hood, thus the force of the current is destroyed, and
the air enters the shaft of ventilator horizontally without force however
strong the wind may be. Greater security against the admission of
wet, snow, or dust is also obtained.
Secondly. We accomplish our object by dispensing with the usual
conical or other shaped hood of the "Watson syphon ventilator," and
place round the top part of the divided shaft (one half of which is
formed higher than the other as much as may be desired to form a
syphon), a series of semicircular fluted or curved plates overlapping one
another, and arranged so as to present alternately a convex and concave
side to the curent of air: Such portions of air as strike the concave
plates are reflected to the inner surfaces of the plates overlapping them,
and by thus reflecting the current from one plate to another its force is
destroyed, midfeathers also being placed at intervals to intercept the
progress of the current between the plates before passing down the shaft.

page_text: The curved plates are arranged in two tiers one above the other, but
separated; the top series of plates being for the outlet or highest part
of the shaft, and the lowest series for the low or inlet side of the shaft.
The plates may be arranged either vertically, diagonally, horizontally, or
otherwise, also they may be angular instead of being curved. In this
kind of ventilator the chambers formed by the upper and lower series of
curved plates are not divided by a diaphram, except so far as the passage
of the high side of the shaft through the lower chamber forms one so
that the foul air may rise to the top chamber or series of plates, and
escape from all sides thereof, fresh air being admitted by the lower series
of plates.
Thirdly. We construct a syphon ventilator shaft with the outlet part a
considerable distance above the inlet, as in the last mentioned, and the
entire shaft is then surrounded by two perpendicular rims or plates at
about equal distances apart. The outlet and inletparts of the shaft are
completely separated by a horizontal diaphram or plate, and the opening
of the outlet part is protected by the outer rim or plate aforesaid, and
the opening to the inlet part is protected by the inner plate or rim, the
passage
of air in both cases being alternately vertical and horizontal.
Both openings are thus protected from the direct action of strong currents
of air.