Improvements in Filters.
Year: 1889

page_text: Date of Application, 6th Sept., 1889
Complete Specification Left, 7th July, 1890-Accepted, 6th Sept., 1890
PROVISIONAL SPECIFICATION.
Improvements in Filters.
I, GEORGE MACDONALD of 7 Quality Court in the County of London, Engineer
do hereby declare the nature of this invention to be as follows:-
In filters constructed according to this invention the water rises in an annular space
or spaces around a central chamber and then passes over the upper lip or rim of and
down through the central chamber which contains a filter block or granular porous or
spongy filtering material of any suitable kind, but by preference the material described
in Gregory and MacDonald's Patent Specification No. 18177 of 1888. The water
having been thus filtered passes through perforations in the bottom of the central
chamber to a suitable outlet channel, or collecting chamber.
As applied to filter beds I place a number of these filters on the bottom of the bed
the filters being formed with a foundation plate upon the middle part of which rises
the annular rim forming the sides of the aforesaid central chamber. Over the chamber
is placed a cap or ball, a narrow space being provided between the outside of the said
rim or chamber and the inside of the cap or bell one or the other being formed with
shallow ribs to divide the annular space between them into a number of narrow
channels, the ribs being continued in between the bottom of the cap and the upper
surface of the foundation plate thus forming passages for admission of the liquid to be
filtered. The central chamber is charged with filtering material, and its bottom is
perforated and communicates with an earthenware or other outlet pipe or channel
which for each filter is provided with an air pipe rising up through the filter bed
material.
For household purposes the filter being placed in a cistern or vessel containing the
water to be filtered is made in a similar manner the bottom flange being smaller or
omitted.
For portable use the filter is made in a similar manner a collecting chamber being
provided at the lower part of the central chamber from which the outlet pipe passes
up. The outer end of this pipe is made suitable for connection to a flexible tube with
mouthpiece.
Dated this 6th day of September 1889.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.
COMPLETE SPECIFICATION.
Improvements in Filters.
I, GEORGE MACDONALD of 7 Quality Court in the County of London 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:-
In filters constructed according to this invention the water rises in an annular space
or spaces around a central chamber or receptacle and then passes over the upper lip
or rim of and down through the central chamber which contains a filter block or
granular porous or spongy filtering material of any suitable kind but by preference
the carbide material described in Gregory and MacDonald's Patent Specification

page_text: No. 18177 of 1888. The water having been thus filtered passes to a suitable outlet
cbannel or collecting chamber.
Fig. 1 of the accompanying drawings is a vertical section through a filter or main
part of a filter constructed according to this invention.
Figure 2 is a plan section. A is a central chamber or receptacle for the filtering
material B in a loose granular or compressed block form. The receptacle A is covered
by a cap or bell C with an intermediate narrow annular space all round between the
rim of the receptacle A and the rim of the cap C, as here shewn however and as
shewn specially in Figure 2 a number of channels are formed between the two because
the receptacle A is formed with a number of shallow ribs (or the interior of the cap B
might be so formed) these ribs being continued in between the bottom of the cap C
and the flange A¹ or foundation plate so that the water is divided into a number of
guided streams. The sectional area of the annular interstice or the number of
annularly arranged interstices between the chamber A and the cap C determines or
regulates the flow of the water. The flange A¹ or foundation plate rests on the bottom
of the filter bed. The water rises between the rim of the cap C and the receptacle A
and then passes down through the carbide or other filtering material B (in a loose
granular or in a compressed block form) and through the perforated bottom A³ into
the outlet D, which may be connected to a pipe E.
Figure 3 is a plan view shewing a number of such filters which may be of round
form as shewn or of square, oblong or polygonal form. Their outlets are connected to
pipes E placed below the filter bed material. For each filter or for every two or more
such an air pipe F is provided which rises up through the filter bed material and the
water above it.
Figure 4 is a vertical section shewing a suitable mode of the application of my filter
to the bottom G of a household or other cistern containing water which is to be filtered
before use.
The rate of filtration is determined by the area between the cap C and
the receptacle A.
In Figure 5 is shewn a form of household filter the filter proper being secured to
the diaphragm G between the upper compartment H for the water to be filtered and
the lower compartment E in which the filtered water is received or collected to be
drawn off as required by a tap. F is an aërating pipe which may be formed in the
wall of the receptacle as shewn. K and Lare layers of filtering media such as granular
carbide and sand.
Figure 6 shows a form of pocket filter the outlet pipe E¹ from the receptacle E being
connected to a rubber hose or the like. The water to be filtered in this case first rises
in the annular space then passes down through the material B and into the collecting
chamber E and can then be sucked up into the pipe E¹.
Figures 7 and 8 shew another form of pocket filter with a block B of moulded
carbide or other filtering material, the perforated bottom A² of Figure 6 being in this
case omitted. I is a cross for holding the receptacle A and the cap C together. The
carbide may be mixed with sugar or saccharine matter for producing cohesion for
moulding; the moulded block is then calcined. As material for the blocks I prefer to
use all waste material which arises in the manufacture of carbide whether of the
ordinary make or made according to the aforesaid Patent 1817788.
The aforesaid filter may be variously combined in jars or other receptacles with
filtering media of different kinds.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
First. A filter in which the liquid to be filtered rises in an annular space or spaces
between the outside of a receptacle open at the top and containing the filtering medium
and a cap placed over such receptacle, the liquid next passing over the lip of the
receptacle and then down through the filtering medium and collecting in a receptacle
or space below substantially as set forth.

page_text: Second. The application of filters as firstly claimed to filter beds in the manner
described and shewn.
Third. The filters for cistern, household and portable use substantially as described
and shewn.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.