Improved Apparatus for Use in Distributing Sewage or other Foul Liquid on Filter Beds.
Year: 1898

page_text: Improved Apparatus for Use in Distributing Sewage or other Foul
Liquid on Filter Beds.
I, WALTER MARDON DUCAT, of 13, Devonshire Terrace, Hyde Park, London, W.,
Colonel, late Royal Engineers, do hereby declare the nature of this invention to be as
follows:-
My invention relates to troughs for distributing sewage or other liquid on filter beds
and has for its object to effect an equal and general distribution of the liquid over the
surface of the filter and prevent the clogging of the troughs with sludge or other
sediment. With this object each trough is mounted to oscillate in such manner as
to become filled up to a certain level and then to automatically become overbalanced
and discharge the whole of its contents on to the filter bed, the trough being self-
righting when empty so that the filling and discharge occur periodically at sufficiently
frequent intervals to effect the object above referred to.
The invention consists in so mounting the trough to rock about a point of support
and so counter weighting the trough that the centre of gravity of the trough (when
filled) will be situated above the axis of oscillation and in a vertical plane to one side
of such axis so that the weight will then preponderate towards that side and the trough
will overbalance whilst, when the trough is relieved of its liquid load, the conditions
will be reversed and the trough will right itself.
A convenient form of trough has one side vertical and the other side inclined out-
wards, although the cross-sectional form might be symmetrical, but placed dis-
symmetrically with regard to the axis of oscillation so that the centre of gravity is
to one side of the vertical plane of such axis. The trough may be supported by
downwardly projecting studs of a continuous rib fixed to the underside of the trough
resting in a grooved seat on an underneath support, the preponderant weight of the
trough towards one side of the axis being counterbalanced by weighted arms project-
ing below and towards the opposite side of the axis so that the centre of gravity of
the counterweighted trough as a whole (when empty) will be towards that side of, and
below the, level of the axial point of support, the trough being maintained in the
upright position for filling by the counterweights coming against stops when this
position is reached. By the shifting of the centre of gravity consequent on the
filling up of the trough the direction of preponderance becomes reversed and the
trough will then oscillate, discharge its contents, and right itself in order to be again
filled.
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London.

page_text: COMPLETE SPECIFICATION.
Improved Apparatus for Use in Distributing Sewage or other Foul
Liquid on Filter Beds.
I, WALTER MARDON DUCAT, of 13, Devonshire Terrace, Hyde Park, London, W.,.
Colonel, late Royal Engineers, 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 :—
My invention relates to tipping troughs for distributing sewage or other liquid
on filter beds and has for its object to effect an equal and general distribution of the
liquid over the surface of the filter and to prevent the clogging of the troughs with
sludge or other sediment. With this object each trough is mounted to oscillate
in such manner as, when filled up to a certain level, to become overbalanced and
discharge the whole of its contents on to the filter bed, the trough being self-
righting when empty.
The invention is illustrated in the accompanying drawings forming part of this
Specification wherein Figures 1 and 2 represent cross sections of a tipping trough
in the upright and tipped positions respectively.
a is the trough mounted to rock about an axis of oscillation and so counter-
weighted that the centre of gravity of the trough (when filled as shewn in Figure 1)
will be so situated with regard to the axis of oscillation that the weight of the trongh
and contents will preponderate and the trough will oscillate and discharge its
contents as shewn in Figure 2, whereupon the conditions will be reversed and the
trough will right itself, and so on, filling and discharging alternately.
A convenient cross sectional form of trough has one side vertical as shewn and the
other side inclined or splayed outwards so that as the trough fills the centre of
gravity of the load will gradually recede from the vertical plane passing through the
axis of oscillation and when the trough tips towards the splayed side the whole
contents will be quickly discharged. Both sides might however be splayed, provided
that the central plane of the trough and consequently the centre of gravity of the
contents is to one side of the vertical plane of the axis of oscillation.
The trough
may be supported by studs such as e downwardly projecting from the bottom of the
trough at suitable intervals and resting by their points in any suitable bearings, such
for instance as slight cavities in the heads of studs d driven into an underneath
support e all the points of oscillation and support being in the same horizontal line.
Or instead of studs e, a continuous rib might be fixed to the underside of the trough
and rest in a grooved seat on the support e. The trough is counterbalanced by
weighted arms f fixed to the trough and projecting downwards and towards the side
of the axis opposed to that at which the trough itself preponderates so that the centre
of gravity of the counterweighted trough as a whole (when empty) will be towards
the side of the counterweight and below the level of the axis of oscillation b, the
trough being there maintained in the upright position, for filling, by the counter-
weight coming against a stop as shewn in Figure 1 when this position is reached.
The counterweight may conveniently be formed of an iron rod g extending longitu-
dinally beneath the trough and held in two or more of the arms f. By the change
of position of the centre of gravity, consequent on the filling up of the trough, the
load preponderates over the counterweight, the trough then oscillates, and discharges
its contents, whereupon the counterweight again preponderates and returns the
trough to the upright position in order to be again filled. The weight of the trough
should be as small as possible in proportion to that of its contents; and the parts
should be so proportioned as to ensure a sufficient turning moment in the direction

page_text: of discharge of the trough when loaded, and a sufficient turning moment in the
reverse direction of the trough when emptied.
Any required number of such troughs would be similarly arranged side by side
above the filter bed, at any suitable distance apart, each being supplied through
a spout from a supply trough common to all.
Having now particularly described and ascertained the nature of the said invention,
and in what manner the same is to be performed, I declare that what I claim is :-
A counterweighted tipping trough adapted to oscillate sideways upon points
of support so situated with regard to the positions of the centre of gravity when
loaded and unloaded respectively that the loaded trough will tip under the
preponderance of the load and the empty trough will right itself under that of the
counterweight substantially as specified.
Dated this 8th day of May 1899
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London.