Improvements in Decanting Apparatus.
Year: 1896

page_text: PROVISIONAL SPECIFICATION.
Improvements in Decanting Apparatus.
CLAUDIUS WALTER RANDS-ALLEN of Sunny Bank East Finchley Engineer and
WILLIAM BOBY of 16 Union Court Old Broad Street London Engineer do hereby
declare the nature of this invention to be as follows:-
This invention relates to an improved method of decanting liquids, that is to say
of drawing off liquid from a tank or other receptacle in such a manner that the
liquid flows off from its upper surface downwards. For this purpose we employ the
device known as a floating arm and our invention consists of methods for enabling
the water to be drawn off from a less distance below its surface, than with the
apparatus before in use and also for enabling this distance to remain more nearly
constant than has been the case heretofore. We also provide a more efficient means
than before for preventing the entrance of scum or floating objects to the mouth of
A difficulty experienced in attempting to draw off the liquid by means of
an arm sustained by a float, or by floats so that its opening approaches very close to
the surface of the liquid is that eddies are formed in the liquid and air enters the
mouth of the arm causing the flow of water to be retarded or to cease. To overcome
this difficulty we employ an arm having its mouth of considerable width and of little
depth, supported by 2 floats, which may be placed either, one at each side of the
opening of the mouth of the arm or front and back of it; between these floats is
placed a thin sheet of metal in such a position that when the mouth is adjusted to
the correct depth below the surface of the liquid, the sheet of metal will touch, or be
very slightly below the surface, and thus prevent air from obtaining access to
the mouth of the arm. The sheet of metal may be turned down at its edges and the
floats, and the edges of the sheet prevent any Hoating objects from obstructing the
mouth of the arm. The mouth of the arm is hinged to the floats by means of tee bars
rivetted or otherwise attached to the floats and the mouth of the arm is sloped in such
a manner that as the arm radiates with the difference of depth of the liquid, the
distance of the edges of the mouth of the arm from the top level of the floats will not
vary considerably, the floats themselves are made flat and of little depth, so that
the difference in weight which comes upon them as the position of the arm varies
will not vary the depth of their immersion considerably. The depth of the mouth
of the arm below the water may be varied by adjusting the distance of the arm itself
in reference to the floats, or by ballasting the floats with water. The vertical
distance between the mouth of the arm and the thin metal sheet may be adjusted by
means of packing pieces or any other suitable device.
Dated this 7th day of May 1896
CLAUDIUS WALTER RANDS-ALLEN.
WILLIAM BOBY.

page_text: Improvements in Decanting Apparatus.
CLAUDIUS WALTER RANDS-ALLEN of Sunny Bauk, East Finchley, Middlesex,
Engineer and WILLIAM BOBY of 16 Union Court, Old Broad Street, London,
Engineer, do bereby 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 method of decanting liquids, that is to say
of drawing off liquid from a tank or other receptacle in such a manner that the
liquid flows off from its upper surface downwards. For this purpose we employ the
device known as a floating-arm, & our invention consists of methods for enabling
the water to be drawn off from a less distance below its surface, than with the apparatus
before in use, & also for enabling this distance to remain more nearly constant
than has been the case heretofore. We also provide a more efficient means than
before for preventing the entrance of scum or floating objects to the mouth of
the arm.
A difficulty experienced in attempting to draw off the liquid by means of an arm
sustained by a float, or by floats so that its opening approaches very close to the surface of
the liquid is that eddies are formed in the liquid and air enters the mouth of the arm
causing the flow of water to be retarded, or to cease. To overcome this difficulty
we employ an arm having its mouth of considerable width and of little depth,
preferably supported by 2 floats, which may be placed either, one at each side of
the opening of the mouth of the arm, or front and back of it; between these floats
is placed a thin sheet of metal in such a position that when the mouth is adjusted
to the correct depth below the surface of the liquid, the sheet of metal will touch,
or be very slightly below the surface, and thus prevent air from obtaining access
to the mouth of the arm. The sheet of metal may be turned down at its edges, and
the floats, and the edges of the sheet prevent any floating objects from obstructing
the mouth of the arm. The mouth of the arm is hinged to the floats by means of
tee bars rivetted or otherwise attached to the floats, and the mouth of the arm is
sloped in such a manner that as the arm radiates with the difference of depth of
the liquid, the distance of the edges of the mouth of the arm from the top level of
the floats will not vary considerably, the floats themselves are made flat and of little
depth, so that the difference in weight which comes upon them as the position of
the arm varies will not vary the depth of their immersion considerably. The depth
of the mouth of the arm below the water may be varied by adjusting the distance
of the arm itself in reference to the floats, or by ballasting the floats with water.
The vertical distance between the mouth of the arm and the thin metal sheet may be
adjusted by means of packing pieces or any other suitable device.
The arm may be constructed with one float only fixed centrally, or nearly so,
above the mouth of the arm, and the sheet of metal may then be fixed to the
attachments holding the float to the arm, and the sheet may be pivotted to these
supports and maintained in a horizontal position by means of a weight upon a lever
hanging downwards at right angles to the sheet of metal, by 2 small supporting
floats or any other suitable device.
In the accompanying drawing A is a floating arm, BB are floats, C is a thin
sheet of metal extending between the floats, and attached to them by brackets DD,
the sheet of metal is turned down at its edges as indicated at E. F is a tee bar, one
of which is fixed at each end of the 2 floats, and by means of which and of the
2 brackets G which are fixed to the sides of the arm, the floats are hinged to the
sides of the arm. There is more than one hole H in the branch of the tee bar, to
allow of adjustment in the distance from the undersides of the floats, to the upper

page_text: edges of the mouth of the arm. JJ are washers between the plate (and the
brackets DD, by reducing or adding to the numbers of the washers the distance
between the plate C and the mouth of the arm can be adjusted. KK are plugs
which may be removed for the purpose of allowing water to be poured into the
floats for the purpose of ballasting them if desired.
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. In a floating arm for decanting liquids the employment of a sheet of metal as
herein described and for the purposes set forth.
2. In a floating arm for decanting liquids the combination of a float or 2 floats
with a mouth of the arm of the form described, a sheet of metal and hinging
arrangements, all as herein described and for the purposes set forth.
Dated this Twenty-ninth day of January 1897.
CLAUDIUS WALTER RANDS-ALLEN.
WILLIAM BOBY.