Year: 1896

page_text: Date of Application, 10th July, 189-Accepted, 17th Oct., 1896
A communication from abroad by PROSPER AUGUSTE MAIGNEN, of 5 Avenue de
l'Opera, Paris, Filter Manufacturer.
We, MAIGNEN'S FILTRE RAPIDE AND ANTI CALCAIRE COMPANY, LIMITED (a
corporate body), of 255 Regent Street, London, W. Filter Manufacturers, 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 relates to improvements in filters, adapted to purify water and
other liquids; and consists, particularly, in the adaptation for the purposes of
filtration of a specially manufactured asbestos cloth, and in the arrangement of
filtering devices combined with these cloths.
One of the qualities most sought after in cloths. designed for filtering purposes
is that of capillarity as distinguished from the passage of water thro' the cloth
merely as a sieve.
Up to the present in the cloths manufactured of pure asbestos, the pores have been
more or less irregular, and in order to obtain good filtration, it was necessary to
add fibrous or powdered materials in order to cover or mask the largest pores.
The asbestos cloth we prefer to use is formed of threads, of which the interior
core is twisted, and the exterior encircling threads are left in fibres, more or less
loose and slack. The interior thus gives the strength, and the exterior the porosity
and capillarity, with the advantage above all, that the loose fibres completely fill
the pores thus making a cloth, of which the porosity is perfectly homogeneous, and
consequently, quite capable of occasioning a considerable improvement in the art of
filtering.
A secondary advantage of this cloth adapted to the use of filtration is that owing
to the impurities remaining on the outside and not entering the cloth the cleansing
of it is much easier.
Whilst we prefer to employ the above mentioned cloth in which the interior of
the threads are twisted and the exterior fibres loose, we may equally adapt to our
devices for filtration, ordinary asbestos cloth submitted to scratching, felting, or
fulling, or to any other process wet or dry having for its object the determination
of a fluffy plush-like surface on the cloth.
We are able to apply these cloths in various convenient ways, and we now
describe, by way of examples, some special arrangements of said cloths and filtering
devices, having regard to the drawings hereto annexed, and to the letters and
figures marked thereon. Like letters refer to similar parts in the different figures.
Figures 1 to 4 are sectional views of filtering devices.
Figures 5 to 8 are sectional views of filtering devices mounted in external cases.
Figure 9 is a detached detail of outlet pipe.
The asbestos cloth S is sewn or manufactured in the form of a sack, and supported
from the interior in various manners, by perforated cylinders or supports ( of
pottery, nickelled copper, or other metal; these cylinders have a single outlet pipe c
(Figures 1 and 3) or better two outlet pipes c c (Figures 2 and 4). In the
arrangements shown in Figures 3 and 4 the asbestos sack is supported by discs d
of earthenware or other substance, disposed in such a manner, that the sack takes
the shape of a concertina or any other convenient form. When the sack is traversed
all its length by a perforated tube c, the filtering device thereby becomes rigid.

page_text: The double communication with the interior serves, above all, to facilitate the
sterilization of the interior of the filtering devices or chambers, as often as it is
necessary, without taking the apparatus to pieces.
We render, also, the use of these asbestos cloths more practicable by placing an
exterior envelope E, equally of asbestos cloth, which has for its object to contain
the filtering chamber or device already described surrounded with filtering media m,
pulverized or fibrous. for instance, of powdered charcoal, (Figure 1), of fibres
(Figure 2);-on Figure 3 can be seen also, fine charcoal, deposited or sprinkled on
the internal filtering cloth S. This envelope E serves as a preliminary clarifier by
retaining the greater portion of the dirt; in this way the interior filtering chamber
and surrounding filtering material are less exposed to the accumulation of dirt and
the filtering device as a whole is also more complete.
Figure 5 shows a filter mounted in a closed vessel D, the filter is carried by a
hollow axis c, furnished with an exterior handle M. It can thus be turned round
in front of a fixed perforated tube t, which performs the work of cleansing by
directing the discharge of liquid over the whole of the filtering device as it revolves.
The funnels e e¹ are used for introducing antiseptics for cleansing both the interior
and exterior of the filter.
When these filters are destined to work directly on the main we make use of
the arrangement shown in Figure 6.
We place two sacks superposed P and Q, conveniently of the same dimensions.
We introduce the water to the interior of P, from whence it flows through the
tissues of the cloth from the interior to the exterior, leaving the dirt and impurities
on the interior-we can then clean them away by means of a jet of water admitted
from the tap r at the inlet, and let them flow through the tap r at the outlet side.
The funnel is used for introducing sterilizing substances into the cleansing fluid.
The cleansing fluid falls from r¹ into the funnel el attached to the lower filtering
device Q.
The water which has passed through the preliminary strainer P filters through Q,
and passes outward by the outlet 2, communication with e' being shut by a cock
provided for that purpose.
In the arrangements of Figures 3, 4, 5, 6 and 7 the asbestos is contracted at
the part z by an asbestos cord or a ring of earthenware, stoneware, or inetal.
It might, perhaps, happen in filters of the concertina shape, that are not rendered
rigid by the hollow perforated tube (see Figures 7 and 8) that the cloth might
press against the orifice of the outlet tube c and hinder the flow as shown in
Figure 8.
In order to avoid this inconvenience we fit the head of the outlet tube as shown
in Figure 7, (also shown detached on a larger scale in Figure 9) with a cup k over
the end of outlet tube c, with many lateral openings to the interior L, protected
by ribs, in such a way that there is always an easy How even though the tube end
may be obstructed by the asbestos cloth.
Having now particularly described and ascertained the nature of our inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1st. The combination with filtering supporting devices of all kinds and dimensions,
of asbestos cloth made with threads, of which the inside is twisted, and the outside
is plushed or fulled.
2nd. In filters, the combination of a supporting device of whatsoever form
covered with asbestos cloth, with an exterior envelope, also of asbestos cloth, and
filtering material either powdered or fibrous, packed within said envelope and
between the said asbestos cloths, substantially as described.
3rd. The combination in filters of two filtering devices, the first a double sack
with filtration from the interior to the exterior, and a through outlet for cleansing,
with or without addition to the interior of filtering material, either powdered or
fibrous, substantially as described.

page_text: 4th. In filtering devices, a second orifice or outlet situated at the opposite end to
the ordinary outlet, or traversing the filtering device entirely, with the object of
putting the interior in communicaton with the exterior for the purpose of facilitating
sterilization by known antiseptics substantially as described:
5th. In a filtering device as described, the socket at the outlet with several lateral
orifices protected by ribs, impossible to be obstructed by the cloth itself, substantially
as described.
6th. The combination of filtering devices and means for the cleansing and
sterilization of the said devices mounted in an external casing substantially as.
described and illustrated herewith.
Dated this 10th day of I.). 1906
FELL & JAMES,
1 Queen Victoria Street, London, E.C., Agents for the Applicants.