Improvements in Filters.
Year: 1892

page_text: Date of Application, 2nd Jan., 1892
Complete Specification Left, 3rd Oct., 1892-Accepted, 12th Nov., 1892
PROVISIONAL SPECIFICATION.
Improvements in Filters.
1, GEORGE MACDONALD of 13 St. Helens Place in the City of London
Mechanical Engineer do hereby declare the nature of this invention to be as
follows:-
66.
In a receptacle by preference circular (or oblong) in horizontal section 1 provide
an upper compartment for the water or other liquid to be filtered, an intermediate
compartment containing the filtering material and a bottom compartment for
reception of the filtered liquid. The bottom of the intermediate or filtering
compartment is provided with vertically upstanding circular walls which reach
nearly to the top of the compartment. The top of the intermediate or filtering
compartment is provided with vertically pendent circular walls which reach nearly
to the bottom of the compartment. The walls of the top and the walls of the
bottom are arranged intermediate of each other so that annular divisions are formed
whereby the liquid descending first through apertures in the top of the filtering
compartment near the inner side of the receptacle and through the filtering material
in the outermost annular division, next rises up through the material in the next
inner one then descends through the next inner one (and it may be so continued one
In this middle part
or more times) finally escaping by an aperture in the middle.
I provide what I may call a special small final filter made according to Fig. 1 of
Specification of my Patent No. 1407289. The material used in this latter is of a
As a suitable
different or finer quality than that contained in the rest of the filter.
filtering material for the main part of the filter I would name Sapperdant" or
the carbide described in the Specification of Gregory and MacDonald's Patent
dated 12th December 1888 No. 18177. The same material but in a more finely
divided state may be used in the special or final filter. The filter may be provided
with an air admission pipe, passing up along one side of the receptacle. If the
filter is made of a rectangular section in plan and especially if constructed for
filtration on a large scale, I may arrange the division walls parallel with the sides
or I provide straight transverse division walls the principle of action being however
the same as in the case of the circular and other arrangements viz. that the liquid
to be filtered passes repeatedly down and up again through the filtering material
and undergoing a final filtration by passing through another or finer filtering
medium in the aforesaid special small filter at the place of exit whether that be in
the middle or at one end of the receptacle. Or the entry may be in the middle
and the exit at both ends, or vice versa. The first filtering compartment may in all
cases contain sand for removing the floating or coarser impurities, such sand being
renewed at suitable intervals as required. The carbide has a chemical action and
an almost continuous or permanent one. Other good filtering material such as
granular animal charcoal may be substituted for the carbide in some or all the
compartments in the final filter.
Dhin and law of Ton 1909

page_text: COMPLETE SPECIFICATION.
Improvements in Filters.
1, GEORGE MACDONALD of 13 St. Helens Place in the City of London,
Mechanical 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 :-
This invention consists in the combination of the filter described in the Specifica-
tion of my Patent dated 6th September 1889 No. 14 72 with filtering compart
ments wherein the water or other liquid follows a downward and upward course all
as hereinafter described.
In a receptacle D such as shewn in the vertical section Figure 1 and having by
preference a circular (or oblong) horizontal section I provide an upper compart-
ment A for the liquid to be filtered, an intermediate compartment containing the
filtering material, and a bottom compartment C for reception of the filtered liquid.
The bottom B of the intermediate or filtering compartment is provided with
vertically upstanding circular walls B', B', which reach nearly to the top B* of the
compartment. The top B' is provided with vertically pendent circular walls B³ B³
which reach nearly to the bottom B. The walls B¹ B of the bottom B and the
walls B' of the top B' are arranged intermediate of each other so that annular
divisions are formed whereby the liquid descending first through apertures in the
top B near its circumference or inner side of the receptacle D and through the
filtering material in the outermost annular division next rises up through the material
in the next inner one and so on up and down as indicated by the arrows, finally
reaching the central division. In this middle part I provide what I call a special
small filter E made according to my aforesaid Specification. The material con-
tained in this latter is of a different or finer quality than that contained in the rest
of the filter; I would name "Sapperdant" or the carbide described in the Specifica-
tion of Gregory and MacDonald's Patent dated 12th December 1888 No. 18177 as
a suitable material in the filter compartments. The same material but in a more
finely divided state may be used in the special or final filter E. The filter may
be provided with an air admission pipe F passing up along one side of the
réceptacle D.
If the filter is made of a rectangular section in plan and especially if constructed
for: filtration on a large scale I arrange the division walls parallel with the sides or
as shewn in the longitudinal sectional view Figure 2 I provide in the receptacle D
straight transverse division walls B3 B8 the principle of action being however the
same as in the circular and other arrangements viz. that the liquid to be filtered
entering by the pipe A. passes repeatedly down and up again through the filtering
material and undergoing a final filtration by passing through another or finer
medium in the aforesaid special small filter E at the place of exit and by the
pipe C whether that place be in the middle. or as here shewn at one end of the
receptacle D. Or the entry may be in the middle and the exit at both ends or,
vice versa.
The first filtering compartment may in all cases contain sand for removing the
floating or coarser impurities, such sand being renewed at suitable intervals as
required. The carbide has a chemical action and an almost continuous or per-
manent one. Other good filtering material such as granular, animal charcoal
may be substituted for the carbide in some or all the compartments and in the
final filter E.
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 :-
1. The combination in a filter of a series of filtering compartments adapted for

page_text: downward and upward filtration with a final filtering appliance such as E, substan-
tially as described and shewn.
2. The constructions of filter shewn on the drawing.
1000
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.