Improvements relating to the Ventilation of Sewers, applicable for other Ventilating Purposes,
Year: 1899

page_text: Date of Application, 22nd Aug., 1899-Accepted, 23th Oct., 1839
DI MULTICATION.
Improvements relating to the Ventilation of Sewers, applicable for
other Ventilating Purposes,
I, EDWARD RICHARD PALMER, of 17, Wickham Road, Beckenham, Kent, Builder
and Sanitary Engineer, do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement:-
The primary object of this invention is to positively create an updraught in
sewer ventilating shafts by means of air propelling fans contained within such
shafts and, preferably, hydraulically operated by water from the main. Far
more effective ventilation is thus secured than with the present method of
relying on natural draught. In cases where the sewer is periodically flushed
from automatic flushing tanks, the waste water from the hydraulic motors of
the fans may be led to said flushing tanks and utilized for filling the same.
My invention may, however, be equally well applied to ventilating shafts used for
other ventilating purposes than sewer ventilation, and the air propelling fans
may be operated by other than hydraulic power, electrically for example.
In creating an updraught in a shaft by means of an air propelling fan
difficulty is experienced in entirely preventing down currents of air, and my
invention further relates to certain details in the construction and arrangement
of the fan and shaft whereby all downdraught is completely obviated.
In order that my invention may be clearly understood, I will now fully
describe the same having reference to the annexed explanatory drawing, in
which:-
Fig. 1 is a vertical section of the lower portion or socket of a sewer ventilating
shaft or column.
Fig. 2 is a horizontal section on line - Fig. 1 and,
Figs. 3 and 4 are details.
a is the lower portion or socket of the ventilating shaft and b is the fan or air
propeller contained therein and mounted on a spindle c. The air propeller
is here shewn as hydraulically operated by means of a simple form of turbine
comprising a chamber or casing d, preferably cast in two flanged portions bolted
together, and having at the top a bush through which the fan spindle c passes.
e is a bridge fixed across the interior of said casing and formed with a counter-
sunk depression which receives and forms a bearing for the conical lower
extremity of the spindle, the countersunk upper extremity of which is engaged
by the point of the screw f adjustable for wear within a stirrup piece g bolted
to the lower edge of a vertical web or division plate h which divides the column a
for a portion of its length above the fan. The function of the web or division
plate h will be hereinafter explained. dare stays by which the turbine casing d
is held in position. Within the said casing there is mounted upon the spindle c
of the air propeller b a set of vertical vanes i, whereon impinges a jet of water,
which, entering the casing under pressure from the main by the inlet pipe k,
causes the air propeller 6 to rapidly revolve and create an updraught in the shaft.
I find, however, that the circular or whirling motion of the air set up by the
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page_text: fan causes a vortex, down the centre of which a certain amount of downdraught
occurs, and the function of the web is to prevent the formation of said vortex
and thus stop all central downdraught. I also find that a certain amount of down
draught takes place between the periphery of the air propeller and the interior
of the shaft, and to stop this I provide the latter with the inwardly projecting
horizontal flange situated just beneath the fan and acting as a baffle ring.
Further, I find that with a fan or air propeller having vanes of the usual shape
as shewn in the detail Fig. 3, that the inner ends of the vanes where they
narrow off are ineffective and a slight downdraught occurs just round the fan
spindle, this defect I obviate by means of a baffle disc m secured upon the
spindle e said disc covering the ineffective portion of the fan or air propeller and
preventing and downdraught around the spindle thereof. n is an outlet pipe
leading from the bottom of the casing by which the waste water is led away
back into the sewer or to any other desired place, but where the sewer is provided
with an automatic flushing tank, I lead the waste pipe n to this tank and fill the
latter thereby, thus avoiding any waste of water. a indicates the inlet from
the sewer.
In order to prevent choking of the small passage through which the water
jet enters the casing or turbine d, I prefer to screw the inlet pipe konto a jet
nozzle screwed into said casing as shewn in the detail Fig. 4 which needs
no further explanation.
Where electric power is handy any suitable electric motor may be employed
for rotating the air propeller in substitution for the turbine.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is: :-
1. The herein described method of ventilating sewers consisting in positively
creating an updraught in the ventilating shaft by means of an air propelling
fan revolved therein.
2. The combination with a sewer or other ventilating shaft of an air propeller
contained therein, hydraulic, electrical or other means for revolving said pro-
peller, and means for preventing the formation of a vortex and obviating all
downdraught, substantially as and for the purpose described.
3. The combination with a sewer or other ventilating shaft, of the turbine with
its feed and waste pipes, and the air propeller revolved thereby, both the turbine
and the air propeller being arranged within the said shaft, substantially as
described.
4. The combination of a ventilating shaft, an air propeller revolvable therein,
a baffle disc or boss carried by the latter, a web or division plate in the shaft
above the air propeller, and a flange or baffle ring beneath the same, substantially
as described.
5. The construction and arrangement of ventilating shaft with air propeller,
hydraulic motor, and means for preventing downward currents, as described and
illustrated.
Dated this 22nd day of August 1899.
E. P. ALEXANDER & SON,
Chartered Patent Agents,
19, Southampton Buildings, Chancery Lane, London, W.C., Agents.