Improvements in and connected with Filters for Water and other Liquids.
Year: 1889

page_text: Date of Application, 17th May, 1889
Complete Specification Left, 17th Mar., 1890-Accepted, 17th May, 1890
PROVISIONAL SPECIFICATION.
Improvements in and connected with Filters for Water and other
Liquids.
We, ROBERT BRUCE of Ethelburga House, Bishopsgate Street Within London,
COLIN CAMPBELL MURRAY GIBSON, of 40 Bickerton Road, Islington, Middlesex
and ERNEST DALBY REEVE of 2 Roskell Road Putney Surrey all Engineers. do
hereby declare the nature of our said invention to be as follows:-
By our improvements the filtering medium to be used would be in the form of a
porous tube or tubes placed in a tank or vessel containing the water or other liquid to
be filtered, such liquid being filtered by percolating from the outside to the inside of
the said porous tube or tubes. One such tank or vessel may contain either a single
such porous tube or one row or series of such porous tubes. The arrangement of
such rows or series may take any form regular or irregular as may be most convenient
such for example as a straight line the whole or part of a circle or any other figure
including any combination of lines or figures and in every such case any or all such
porous tubes may be placed with their axes either vertical horizontal or inclined at
any angle to the horizontal. One end of each such porous tube is closed by a cap
provided with a socket for the reception and closing or joint of this end of the tube
the other open end being inserted and jointed in a socket (which we herein term the
exit socket") upon the end of a cylindrical nozzle (called the "exit nozzle") which
is inserted in and capable of rotating in a stuffing box, such stuffing box either
communicating directly, with an outlet in the side or bottom of the tank, or with the
interior of a pipe, conduit or hollow chamber or passage placed in any convenient
position in the tank for the purpose of collecting the fiftered liquid from the interior
of the hollow tube or tubes and discharging such filtered liquid to drawing-off pipes
or vessels outside the tank. The sockets of the cap and exit nozzle are drawn towards
one another so as to press tightly against their respective ends of the porous tube by
means of a bolt or bolts. One end of such bolt or bolts being attached to the
exit socket whilst a nut engaging with a screwed thread formed towards the other
Where only
end of the said bolt or bolts presses against the outer face of the cap.
one such bolt is used it is placed inside and concentric with the porous tube but there
may instead be used a series of two or more such 'bolts connecting the cap and exit
sockets in which case the said bolts are more conveniently placed externally to the
porous tube as when the porous tubes are made large. In every case the position of
the axis of the porous tube (and consequently of its exit nozzle) is kept true or
concentric which may be done for instance by means of a trunnion, or a centre,
(similar to a lathe centre) such trunnion or centre being either attached to the outer
face of the cap and engaging with a bearing supported by a suitable projection
attached to the structure of the tank, or being attached to or mounted upon such
projection and engaging with a bearing formed upon the outer face of the cap or
consisting of an outer prolongation of the central bolt where such bolt is used. In
either such case a spring or set screw or some such contrivance may be arranged so
as to exert pressure against the outer face of the cap or otherwise so as to tend to
prevent the exit nozzle from rising out of the stuffing box in which it rotates. Where
any porous tube is placed with its axis vertical or nearly so and when it happens that
the filtered liquid is not pumped or drawn off with sufficient rapidity to prevent the
accumulation of air within the porous tube during the process of filtration, communi-
cation may be maintained between the interior of the said porous tube and the outer
atmosphere by means of a small pipe (which we call the air pipe") open at both
ends and attached to the cap, its lower end being open to the interior of the porous
tube and its upper eud standing above the surface level of the liquid in the tank ;

page_text: t
where a central bolt is used to draw the two sockets together, suoh air pipe may
consist of a prolongation of the said central bolt, which in such a case is made hollow
from its upper (and open) end to some little distance below the upper end of the
porous tube, a small hole being drilled through the side of the tube thus formed,
immediately below the under face of the cap. The upper end of the said air pipe
may be provided with a valve or plug. Around the periphery of the exit socket is
formed or fixed a toothed wheel (or it may be a screw wheel or pulley) which being
actuated through suitable driving mechanism, the porous tube with its cap and exit
nozzle may be caused to rotate about its axis at will, and such rotatory motion may
be applied to a single porous tube or to any number of porous tubes simultaneously.
The object of such rotatory motion is to facilitate the cleansing whenever required of
each porous tube by successively exposing every side thereof to the action of a jet of
steam or of hot or cold water or other diluent directed against the outer surface
of the tube. The stuffing boxes in which the nozzles of the exit sockets of a series of
the porous tubes rotate, may be arranged so as to forin branches from a pipe or
hollow chamber forming the close hollow rim or web of a wheel (whose circumferential
form may be either circular, polygonal, or otherwise shaped as may be convenient)
such branches, and consequently the corresponding porous tubes, having their axes'
parallel to the axis of the wheel. The arms and boss of such wheel are also hollow,
their interiors communicating with one another and also with the interior of the
hollow rim or web of this wheel. To a central opening in the end of the hollow boss
of such wheel is attached a cylindrical nozzle whose axis coincides with that of the
wheel, and this nozzle passes through, and is capable of rotating in, a stuffing box
attached to the side, end, or bottom of the tank, and this forms the only means of exit for
the filtered liquid from the said tank and set of porous tubes. The hollow rim or
wheel would have fixed or formed on it a toothed periphery or other equivalent to
rotate it and the perforated filtering tubes from suitable driving motive mechanism.
In such an arrangement as that just described, the trunnions or centres herein before
described in connection with the caps are attached to the latter, and are supported
by or rotate in bearings which are not directly attached to the structure of the tank
itself, but formed upon or attached to a series of arms radiating from a boss or hub
concentric with and placed at a suitable distance from the hollow rimmed wheel
before described, and rigidly held in their proper position by the said boss being keyed
or fixed upon a central spindle (whose axis coincides with that of the said wheel) one
end of which spindle is fixed to the face of the boss of the said wheel, its opposite end
resting and being capable of rotating in a bearing attached to the structure of the
tank. The object of such an arrangement as that just described is to facilitate the
inspection, cleansing, repair or renewal of the porous tubes, by not only allowing of
the rotation of each individual tube about its own axis, but also (and especially when
the porous tubes are placed horizontally) by permitting the bringing of any particular
tube of the series into the most convenient position for such inspection, cleansing,
repair or renewal. The entire system of porous tubes may if desired be kept in
continuous rotation, thus reducing the accumulation of material on the filtering
surface and doing away with frequent special cleansing operations. Each porous tube
of such a series as that just described, instead of being arranged to rotate about its
own axis, may however be fixed, the one end of the tube being inserted in a socket
formed or fixed around an opening in the face of the hollow rim of a wheel similar to
that before described, whilst the cap engages with or is supported upon the before
described radial arms by means of a guide or guides which allow of motion only in
the direction of the length of the porous tube. In this case it is not necessary to
employ a bolt or bolts (either internal or external to the porous tube) in order to
draw the two sockets together and so to secure them upon their respective ends of
the porous tube. This result may be effected by means of a spring or set screw (or
several of them) interposed between the outer face of the cap and the radial arm upon
which the cap is mounted, such spring or set screw forcing the cap away from the
radial arm and towards the opposite socket. Suitable mechanism, as for instance a
screw and nut, lever, or cam, may be employed to withdraw the cap from the end of

page_text: the porous tube at will. In the case of such a series of fixed porous tubes as that just
described, the most suitable, and as regards filtering area the most economical, form
of cross section for the porous tube is sector-like the flat radial sides thus given to the
porous tubes allowing the individual members of the whole series to be placed in close
proximity to one another, whilst permitting of ready inspection of every portion of the
surface of each.
In the same tank or vessel two or more such systems of porous tubes in con-
nection with a hollow rimmed or webbed wheel or wheels, all as hereinbefore
described. may be used, such systems having a common axis and being placed
end to end. Thus for example one set of radial arms placed between two such
hollow rimmed wheels may accommodate two series of caps with their porous
tubes, the one series of porous tubes discharging their contents into one hollow
rimined wheel whilst the other series discharge into the other hollow rimmed
wheel. In such a case each hollow rimmed wheel may have its own nozzle
working in and discharging through a stuffing box in the side of the tank, or in
place of a nozzle, one of the hollow rimmed wheels may have a trunnion rotating in a
bearing attached to the side of the tank, whilst in place of the solid central spindle
herein before described, a central pipe whose interior is in connection with the last
mentioned hollow rimmed wheel may connect and support the two hollow rimmed
wheels and the intermediate boss with its projecting radial arms, and may convey the
filtered liquid to that hollow rimmed wheel which has an exit nozzle. Or two such
systems of porous tubes may be otherwise combined, one hollow rimmed wheel being
placed between two sets of radial arms, such hollow rimmed wheel having openings
with sockets or stuffing boxes upon both its faces, and its central exit nozzle or nozzles
being prolonged so as to work in a stuffing box at either or both ends of the tank.
Any set of the radial arms hereinbefore mentioned, may be combined so as to form
one complete rotating disc or frame.
With a view to effecting double, triple, or further filtration simultaneously within
the same tank or vessel, the porous tube or tubes contained in such tank may be com-
pounded in various ways.
Thus for example two or more porous tubes of different diameters, the larger being
slipped concentrically like sleeves over the smaller (a convenient space being however
left between the inner surface of the larger tube and the outer surface of the next
inner smaller tube) may be used between a single pair of sockets, such sockets being
adapted accordingly, so as to receive all the ends of the porous tubes. The inner
tubes between any one pair of sockets, instead of being slipped concentrically over one
another as above described, may be clustered or arranged externally to one another
like the sticks in a faggot, being however, all enclosed within one outer tube. There
may also be two or more concentric outer porous tubes enclosing a cluster of two
or more inner tubes external to one another, whilst each of the said inner tubes
may have other tubes of smaller diameter arranged either concentrically or in a cluster
within it.
In all compound arrangements of porous tubes such as those above described, the
liquid in process of filtration passes successively from the exterior of the outermost
porous tube to the interior of the innermost porous tube or tubes, the only final exit
for the filtered liquid being from the interior of the innermost porous tube or tubes
by way of an opening in the exit socket of each such innermost porous tube, but there
is no exit from any porous tube (not being an innermost tube) except through the
next.inner porous tube.
In the case of any such compound arrangement of porous tubes as above described,
the interstices between the inner face of any porous tube enclosing another porous tube
and the outer face of such other enclosed porous tube may be wholly or partially
filled with any suitable filtering material in a granular or powdered form.
In the construction of the said porous tubes, any suitable material or combination of
materials may be employed as the filtering medium, and should such material or
combination of materials so employed be of insufficient strength if used by itself, the
structure of the tube may be strengthened by a framework of any convenient material
13

page_text: or form. Thus for example the filtering medium, may consist of charcoal, coke;
animal or other carbon, porous earthenware or clay, natural or artificial stone, wire
gauze of any kind, perforated sheet metal or other perforated material, vegetable or
mineral cloth stretched over and suitably, secured upon an open frame work of metal
or of other material, or over a cylinder or. tube of wire gauze or perforated metal or
other perforated material. Or the porous tube may be built up of a succession of
rings or short tubes of the selected material or of different materials, such rings being
cemented or otherwise fastened together or having rings of suitable packing inter-
posed between each two adjacent lengths of filtering material. Or the porous tube
may consist of a succession of rings or grummets of material as for instance asbestos,
each such ring or grummet being either with or without a core, it being however
advisable to interpose a flat ring of rigid material between each two adjacent grummets
in order to preserve the form and stability of the latter when the sockets are drawn
together. Or such porous tube may be built up of separate plates, such plates being
either flat or concavo-convex, or of any other convenient form and being secured to
one another by bolts, cement, or other suitable means, and either with or without a
framework of rigid or elastic material, such framework being formed either in one
piece or built up of several separate portions and the joints between any of the portions
of the said framework, or between any of the said plates and any portion or portions
of the said framework, may be made secure with any suitable packing or jointing
material. Where the rigidity of the material of which the porous tube is formed, or
other cause renders it advisable to do so, a ring of suitable packing may be inter-
posed between each end of the said porous tube and the bottom of the socket in which
it is inserted. The said porous tubes may be of any convenient dimensions and may
have any suitable and convenient form of cross section. Such for example as the
circular, polygonal, square, triangular, elliptical or other regular or irregular forms,
including the sector of a circle, as herein before more particularly described.
In the cleansing of any single porous tube or series of porous tubes as hereinbefore
described, there may be used steam, compressed air or gas, hot or cold water, or other
diluent, singly or in any combination, and either applied to the interior or exterior
of the said porous tube or tubes.
In this invention we do not confine ourselves to the details of the mechanical
arrangements mentioned or described in the foregoing specification, as we may employ
other equivalent mechanical contrivances or devices (such as for securing and rotating
the said hollow filtering tubes described) which we may deem convenient and which
may suffice to produce the same results.
Instead of the aforesaid hollow rim wheel we sometimes use pipes which are
adapted to receive the porous tubes and are connected to the outlet nozzle suitable
gearing being provided for effecting rotation.
Dated this 17th dose of I
1000
W. R. M. THOMSON & Co.,
Agents.
COMPLETE SPECIFICATION.
Improvements in and connected with Filters for Water and other
Liquids.
We, ROBERT BRUCE, of Ethelburga House, Bishopsgate Street, Within, London
COLIN CAMPBELL MURRAY GIBSON of 40 Bickerton Road Islington Middlesex, and
ERNEST DALBY REEVE of 2 Roskell Road, Putney Surrey, all Engineers, do hereby
declare the nature of our said invention and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
.statement :-
'
By our improvements the filtering medium to be used would be in the form of a
porous tube or tubes placed in a tank or vessel containing the water or other liquid to
be filtered such liquid being filtered by percolating from the. outside to the inside of
the said porous tube or tubes, One such tank or vessel may contain either a single

page_text: such porous tube or one row or series or several separate and distinct rows or series of
such porous tubes. The arrangement of such rows or series may take any form,
regular or irregular as may be most convenient, such for example, as a straight line,
the whole or part of a circle, or any other figure, including any combination of lines
or figures, and in every such case any or all such porous tubes may be placed with
their axes either vertical, horizontal or inclined at any angle to the horizontal.
In order that our invention may be more readily understood we will describe the
same with reference to the accompanying drawings of which
Figures 1, 2 and 3 sheet 1 are sectional elevations of various forms of filtering
apparatus with vertical filtering tubes.
Figure 4 sheet 2 represents a horizontal section through one of the porous tubes A
Figures 1 and 3 sheet 1.
Figure 5 is a like view through the porous tubes A. A' Figure 2.
Figure 6 is a sectional view of a modified arrangement in which A as before
represents an outer porous tube whilst A* are smaller porous tubes contained therein,
the interiors of which all lead to a common exit.
Figure 7 shows a tank in sectional end elevation provided with two rows of porous
tubes and
Figure 8 is a plan thereof.
Figure 9 sheet 3 is a sectional view of a filtering apparatus with porous tube
mounted horizontally.
Figure 10 represents outside end elevation thereof with manhole cover Z removed
and Figure 11 is a section through line y Figure 9.
Figure 12 is a somewhat similar view to Figure 9 and
Figure 13 is a section on line - Figure 12.
Figure 14 sheet 4 is longitudinal elevation partly in section of an apparatus with
several porous tubes mounted around a common revolving axis and
Figures 15 and 16 are sectional end views respectively looking from the centre
towards left and right hand ends of apparatus shown in Figure 14.
Figure 17 sheet 5 is sectional elevation of a somewhat similar arrangement the
essential difference being the application of fixed tubes whose cross section is
approximately a sector of a circle, and
Figures 18 and 19 are sectional end views respectively looking from centre towards
left and right hand ends Figure 17.
Figure 20 sheet 6 is sectional elevation of a modified form of apparatus.
The same letters of reference indicate like or equivalent parts in all the Figures.
Referring to Figure 1 of the drawings it will be seen that one end of each such
porous tube A is closed by a cap B provided with a socket for the reception and
closing or joint of this end of the tube A by means of any kind of suitable packing a
when necessary all as more particularly hereinafier described. The other open end is
inserted and jointed in a socket C (which we herein term the "exit socket") upon
the end of a cylindrical nozzle D (called the "exit nozzle") which is inserted and
capable of rotating in a stuffing box E forming a bearing, represents the packing
which may consist of a ring or rings of any suitable material such as asbestos yarn.
The stuffing box communicates directly with an outlet in the side or bottom of the
tank T, and the interior of a pipe F preferably arranged as shown. The whole
weight of the tube and parts connected thereto rests preferably on a stud or centre D*
which in the cases here shown finds a convenient bearing at the bottom of the outlet
pipe F. By this means the friction set up in the stuffing box on revolving the tube
is reduced to a minimum.
The said pipe F may be of course placed in any convenient position in the tank for
the purpose of collecting the filtered liquid from the interior of the porous tube or
tubes A and discharging such filtered liquid by drawing off pipes or vessels outside
the tank. The stuffing box might also be in a partition separating the tank into two
divisions so that the filtered liquid is discharged from the tube A into the second
chamber thus formed, whence the filtered liquid can be drawn off when required.
Or the pipe F may be dispensed with and the water may discharge direct into the

page_text: reservoir .or other place as required. The cap B and socket Care drawn towards
one another so as to press tightly against the ends of the porous tube A by means
of a bolt or bolts G one end of such bolt or bolts being attached or jointed to the
exit socket C whilst a nut H engaging with a screw thread formed towards the other
end of the said bolt G presses against the outer face of the cap B. The bolt G is as
shown jointed to the gudgeon g on the socket ( so as to allow of a little play if required."
Where only one such bolt is used it is as here shown placed inside and concentric with the
porous tube A but there may instead be used a series of two or more such bolts G as shown
n. Figures 12 and 13 connecting the cap and exit sockets in which case the said bolts
are more conveniently placed externally to the porous tube as for instance when
the porous tubes are made large. In every case the position of the axis of the
porous tube (and consequently of its exit nozzle D) is kept true or concentric. This
may be done for instance by means of a trunnion or a centre I such trunnion or
centre being either as shown in Figure 12 attached to the outer face of the cap, and
engaging with a bearing supported on the structure of the tank, or as shown being
attached to or mounted upon such a projection or bracket K Figures 1, 2 and 3 and
engaging with a bearing formed upon an outer prolongation of the central bolt G
or in any other suitable manner. The bracket K may conveniently in this case be
made so as to be capable of being moved from its normal position and being swung
aside when the tube or other parts are to be removed or placed in the tank. In
either such case a spring L and centre I as shown in Figure 3 or set screw as shown
in Figure 1 or some such contrivance such as a pin L Figure 2. Engaging in a
groove in the bolt G may be arranged so as to exert pressure against the cap or
otherwise so as to tend to prevent the said exit nozzle from rising out of the stuffing
box in which it rotates. Where any porous tube is placed with its axis vertical or
nearly so and. when it happens that the filtered liquid is not pumped or drawn off
with sufficient rapidity to prevent the accumulation of air within the porous tubo
during the process of filtration, communication may be maintained between the
interior of the said porous tube and the outer atmosphere by means of a pipe M
Figures 2 and 3 (which we call the "air pipe") open at both ends and attached to the
cap, its lower end being open to the interior of the porous tube A and its upper
end standing above the surface level of the liquid in the tank. Where a central
bolt is used as in Figure 1 to draw the two sockets B and C together, such air pipe
may consist of a prolongation of the said central bolt G, which in such a case is made
hollow from its upper (and open) end to some little distance or all the way as the
case may be below the upper end of the porous tube, a small hole N' being drilled
through the side of the pipe thus formed, immediately below the under face of the
cap. The opening at the upper end of the said air pipe M may be provided with a
valve or plug N Figures 2 and 3. Around the periphery of the exit socket C is
formed or fixed a toothed wheel O (or it may be a screwed wheel or pulley) which
being, actuated through suitable driving mechanism as for instance by means of a
pinion
or worm P the porous tube A with its cap B and exit nozzle D may be caused
to rotate about its axis at will, and such rotatory motion may be applied to a single
porous tube A or to any number of porous tubes simultaneously as shown also in
Figures 7 and S. The object of such rotatory motion is to facilitate the cleansing
whenever required of each porous tube by successively exposing every side thereof
to the action of a washing or purifying agent such as a jet of steam or of hot or cold
water or other diluent or agent against the outer surface of the tube.
Figure 3-represents a modification which may conveniently be applied in a case
where it is advisable to be able to ensure a sound joint in the stuffing box without the
necessity for removing the exit socket and nozzle. The exit nozzle is formed in
two parts D and D', the former being in one with the exit socket C whilst the other
part D is made capable of sliding therein being prevented from turning independently
or apart from the socket C by means of a stud d or its equivalent sliding in a key
way in the inner face of the outer nozzle D. The packing bis held and compressed
between the lower extremity of the outer nozzle D and a shoulder formed upon the
lower extremity of the inner nozzle D₁, the stud D² being in this case attached to the

page_text: ,inner nozzle D¹. The upper end of the inner nozzle D₁ is screw threaded and has a
nut g' thereon which serves to exert the necessary pressure upon the socket C and
outer nozzle D for compressing the packing which is held between the nozzle D and
a shoulder formed on the lower part of the part D as before described. Where in
such a case a central bolt is used as shown, the said bolt may most conveniently be
attached to the nut g'. And in order that the packing in the stuffing box may be
compressed whilst the porous tube A is in position and without materially affecting
the pressure between the cap B and exit socket C, we do not necessarily form a screwed
thread upon the bolt itself but may employ two hand wheels H H situated, near
the top. The upper one H' which can be jammed on the bolt G at any required
height serves for the double purpose of enabling the nut to be screwed down and
also forms a stop or thrust bearing for the other hand wheel EL. The lower part of the
boss of this hand wheel H is prolonged and screwed externally into the upper part of
the air pipe M and it may be prevented from turning therein by means of the set
screw m or its equivalent.
Figures 7 and 8 represent a. tank provided with eight porous tubes A the
individual arrangement of the tubes being the same as described with reference to
Figures 3. The tubes are however mounted in such manner that one pinion P serves
to actuate four tubes by gearing with their toothed rims O, the brackets K being
suitably mounted on a T shaped girder bolted on to brackets fixed on each end of
the tank T.
Figures 9. 10 and 11 represent a somewhat similar arrangement to that described
with reference to Figure 2. the essential difference being that the tube A is mounted
horizontally in the tank T and the end of the bolt G, runs in a bracket K fixed to
the side of the tank. The bracket may however be mounted on the bottom of the
tank if the sides be not strong enough. The tube A may be conveniently rotated by
worm wheel gearing in the same way as previously described and several of the
tubes may be mounted side by side in a tank T motion being communicated by the
shaft p running the whole length of the tank.
Figures 12 and 18 represent a very similar construction, the essential differences
being that the tube is revolved by bevel gearing OP. The central bolt G Figure 9
is replaced by outside bolts G and the cap B has a trunnion in the centre running in
a bearing K. The exit nozzle is kept in its proper position in the stuffing box by
means of set screw L provided with a chack nut.
The stuffing boxes in which the nozzles of the exit sockets of a series of the porous
tubes rotate may be arranged so as to form branches from a pipe or hollow chamber
forming the close hollow rim or web of a wheel (whose circumferential form may be
either circular, polygonal or otherwise shaped as may be convenient) such branches
and consequently the corresponding porous tubes A having their axes parallel to the
axis of the said wheel. The arms and boss of such a wheel are also hollow their
interiors communicating with one another-and also with the interior of the hollow
rim or web of the wheel.
A similar arrangement is shown in Figures 14 15 and 16 but in this case only the
arms E are hollow and a porous tube A is mounted at the end of each such arm.
To a central opening in the end of the hollow boss of such wheel E is attached a
cylindrical nozzle D whose axis coincides with that of the wheel and this nozzle paššes
through and is capable of rotating in a stuffing box E³ attached to the side, of the
tank and this forms the only means of exit for the filtered liquid from the said tank
and set of porous tubes. The hollow rim or wheel E¹ would have fixed or formed on
it a toothed periphery or other equivalent to rotate it, by means of a pinion Por
otherwise and with it of course the porous filtering tubes froin suitable driving
motive mechanism. In such an arrangement as that just described, the, trunnions or
centres herein before described in connection with the caps are supported by or
rotate in bearings which are attached to a series of arms K' K2 radiating from a boss
or hub concentric with and placed at a suitable distance from the hollow rimmed
wheel before described, and rigidly held in their proper position by the said boss
being keyed-or fixed upon the central spindle G₁ (whose axis coincides with that

page_text: of the said wheel) one end of which spindle is fixed to the face of the boss D³
of the wheel E' its opposite end resting and being capable of rotating in a
bearing K attached to the structure of, the tank T. The tubes A are kept in their
proper position by means of the nuts H which run on the bolts G. The bolts are as
before described carried in centres I or their equivalents to keep the nozzles D down.
in place in their stuffing boxes E.
The arms K' may as shown be jointed on to arms K² so as to permit of swinging
out of the way when a tube A is removed bodily with its nozzle. The sockets C
are flanged so as to permit of their being turned round by hand but this motion
might also be obtained by gearing if desired. The object of such an arrangement as
that just described is to facilitate the inspection, cleansing, repair and renewal of tho
porous tubes A by not only allowing of the rotation of each individual tube about its
own axis but also (and especially when the porous tubes are placed horizontally) by
permitting the bringing of any particular tube of the series into the most convenient
position for such inspection, cleansing, repair or renewal. The entire system of
porous tubes may if desired be kept in continuous rotation thus reducing the
accumulation of foreign material on the filtering surface and doing away with
frequent special cleansing operations. Each porous tube of such a series as that just
described instead of being arranged to rotate about its own axis, may however be
fixed, the one end of the tube being inserted in a socket formed or fixed around an
opening in the face of the hollow rim of a wheel similar to that before described
whilst the cap engages with or is supported upon the before described radial
arms by means of a guide or guides which allow of motion only in the direction
of the length of the porous tube. In this case it is not necessary to employ a bolt
or bolts (either internal or external to the porous tube) in order to draw the two.
sockets together and so as to secure them upon their respective ends of the porous
tube. This result may be effected by means of a spring or set screw (or several of
them) interposed between the outer face of the cap and the radial arm, upon which
the cap is mounted such spring or set screw forcing the cap away from the radial arm
and towards the opposite socket. Suitable mechanism as for instance a screw and nut,
lever or cam, may be employed to withdraw the cap from the end of the porous tube
at will. In the case of such a series of fixed porous tubes as that just described the
most suitable, and as regards filtering area the most economical form of cross section
for the porous tube is sector like see Figures 17 to 19 inclusive the flat radial sides
thus given to the porous tubes A allowing the individual members of the whole series.
to be placed in close proximity to one another whilst permitting of ready inspection of
every portion of the surface of each and owing to the peculiar form of these tubes it
is apparent that under some circumstances such a system of tubes may even be bolted
or fixed in position so as not to revolve and yet permit of their being readily cleansed.
Under these circumstances the tubes might be placed in a rectangular tank and would
be arranged to fill up the corners so as to increase the filtering surface as much as
possible. Two or more such systems of porous tubes may be arranged in the same
tank in connection with a hollow rimmed or webbed wheel or wheels all as herein-
before described, such systems having a common axis and being placed end to end.
Thus for example one set of radial arms placed between two such hollow rimmed
wheels may accomodate two series of caps with their porous tubes the one series of
porous tubes discharging their contents into one hollow rimmed wheel whilst the other
series discharge into the other hollow rimmed wheel. In such a case each hollow
rimmed wheel may have its own nozzle working in and discharging through a stuffing
box in the side of the tank, or in place of a nozzle one of the hollow rimmed wheels
may have a trunnion rotating in a bearing attached to the side of the tank. Whilst
in place of the solid central spindle G₁ hereinbefore described, a central pipe whose
interior is in connection with the last mentioned hollow rimmed wheel may connect
and support the two hollow rimmed wheels and the intermediate boss with its pro-
jecting radial arms, and may convey the filtered liquid to that hollow rimmed wheel
which has an exit nozzle. Or as shown in Figure 20 two such systems of porous
tubes A may be otherwise combined, one hollow rimmed wheel E¹ being placed between

page_text: wo sets of radial arms K' such hollow rimmed wheel El having openings with
sockets C or stuffing boxes upon both its faces and its central exit nozzle D'or nozzles
being prolonged so as to work in a stuffing box E³ at either or both ends of the
tank.
Any set of the radial arms, hereinbefore mentioned may be combined so as to form
one complete disc or frame.
With a view to effecting double, triple, or further filtration simultaneously within
the same tank or vessel, the porous tube or tubes contained in such tank may be com-
pounded in various ways.
Thus for example as shewn in Figures 2 and 5 sheets 1 and 2 two or more porous
tubes may be used of different diameters, the larger A being slipped concentrically
over the smaller A¹ (a convenient space being however left between the inner surface
of the larger tube A and the outer surface of the next smaller tube A'). All such
arrangements of tubes are preferably mounted between a single pair of sockets B and C.
see Figure 2 such sockets being adapted accordingly, so as to receive and close all the
ends thereof, but a pair or series of sockets or caps may be employed one within
another if found convenient. The inner tubes between any one pair of sockets, instead
of being slipped concentrically over one another as above described may as shewn
at A in Figure 6 be clustered or arranged externally to one another like the sticks in
a faggot being however all enclosed within one outer tube A.. There may also be two
or more concentric outer porous tubes enclosing a cluster of two or more inner tubes
external to one another, whilst each of the said inner tubes may have other tubes of
smaller diameter arranged either concentrically or in a cluster within it. In all
compound arrangements of porous tubes such as those above described the liquid in
process of filtration passes successively from the exterior of the outermost porous
tube to the interior of the innermost porous tube or tubes, the only final exit for the
filtered liquid being from the interior of the innermost porous tube or tubes by way of
an opening into the exit socket of each such innermost porous tube, but there is no
exit from any porous tube (not being an innermost tube) save through the next inner
porous tube. In the case of any of the compound arrangements of porous tubes
herein described the space between the inner face of any porous tube enclosing
another porous tube and the outer face of such other enclosed porous tube may be
wholly or partially filled with any suitable filtering material in a granular or powdered
form. In the case of compound tubes having the spacos between them filled as
described with granular or powdered filtering material the outer and inner tubes may
be made as one so as to form a convenient receptacle for containing the said filtering
material. In the construction of the said porous tubes any suitable material or com-
bination of materials may be employed as the filtering medium and should such
material or combination of materials so employed be of insufficient strength if used
by itself the structure of the tube may be strengthened by a framework of any con-
venient material or form. Thus for example the filtering medium may consist of
charcoal, coke, animal or other carbon, porous earthenware or clay, natural or
artificial stone, wire gauze of any kind, perforated sheet metal or other perforated
material, cloth of any kind stretched over and suitably secured upon an open frame-
work of metal or of other material or of different materials or over a cylinder or tube
of wire gauze or perforated metal or other perforated material. Or the porous tube
may be built up of a succession of rings or short tubes of the selected material such
rings being cemented or otherwise fastened together or having washers or flanged
rings of suitable packing interposed between each two adjacent lengths of filtering
material. Or the porous tube may consist of a succession of rings or grummets of
suitable compressible material, as for instance asbestos, each such ring or grummet
being either with or without a core, it being however advisable to interpose a flat
ring of rigid material between each two adjacent grummets in order to preserve the
form and stability of the latter when the sockets are drawn together. Or such porous
tube may be built up of a series of separate plates, such plates being either flat or
concavo-convex or of any other convenient form and being secured to one another by
bolts cement or other suitable means, and either with or without a framework of rigid
B

page_text: or elastic material, such framework being formed either in one piece or built up of
several separate portions and the joints between any of the portions of the said frame-
work, or between any of the said plates and any portion or portions of the said
framework, may be made secure with any suitable packing or jointing material.
Where the rigidity of the material of which the porous tube is formed or other canse,
renders it advisable to do so, a ring of suitable packing as shown at a in the drawings
may be interposed between each end of the said porous tube and the bottom of the
socket in which it is inserted.
The said porous tubes howsoever composed or built up may be of any convenient
dimensions and may have any suitable and convenient form of cross section. Such
for example as the circular polygonal, square, triangular elliptical or other regular
or irregular forms, including the sector of a circle, herein before more particularly
described.
In the cleansing of any single porous tube or series of porous tubes as herein-
before described there may be used steam compressed air or gas, hot or cold water,
or other diluent or agent singly or in any combination and either applied to the
interior or exterior of the said porous tube or tubes, or to both interior and exterior
simultaneously.
In this invention we do not confine ovrselves to the details of the mechanical
arrangements mentioned or described in the foregoing specification as we may
employ other equivalent mechanical contrivances or devices (such as for securing
and rotating the said porous filtering tubes described) which we may deem convenient
and which may suffice to produce the same results.
>
Instead of the aforesaid hollow-rim wheel E' we sometimes use pipes which are
adapted to receive the porous tubes and are connected to the outlet nozzle; suitable
gearing being provided for effecting rotation.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is
First. An apparatus for filtering water and other liquids, consisting of a porous
tube or tubes (provided with suitable exit or exits) and mounted in a tank or
other receptacle containing the liquid to be filtered with means for permitting of
the moving of such tube or tubes for repairs or inspection and for rotating or
moving same to facilitate or cause the cleansing thereof substantially as described.
Second. An apparatus for filtering water and other liquids consisting of a porous
tube mounted between a cap and socket held together being also provided with an
exit nozzle and stuffing box and means for steadying the said porous tube and its cap
and for keeping the nozzle in its proper position in said stuffing box substantially as
described and shewn on the drawings with reference to Figures 1, 2 and 3.
Third. The improved construction of filtering apparatus consisting of a series of
vertical porous tubes mounted in a tank with means for rotating said tubes allowing
of adjustment of the packing in the stuffing boxes and for permitting the rotation of
the porous tubes substantially as described with reference to Figures 7 and 8.
Fourth. In a filtering apparatus for water and other liquids the employment of a
series of porous tubes contained concentrically one within the other substantially as
set forth.
Fifth. In a filtering apparatus for water and other liquids the employment of one
or more outer porous tubes, one being mounted concentrically in the other if more
than one be used, and having two or more smaller porous tubes contained therein
substantially as described.
Sixth. The improved construction of filtering apparatus consisting of a horizontal
porous tube mounted between a cap and socket provided with exit nozzle and stuffing
box with means for making a watertight joint and also for allowing of the rotation of
the said porous tube substantially as described with reference to Figures 9, 10 and 11
and 12 and 13.
Seventh. The improved construction of filtering apparatus substantially as described

page_text: with reference to Figures 14, 15 and 16 consisting of a series of horizontally mounted
porous tubes provided with means for facilitating removal thereof when required and
having exit nozzles all leading to one common exit nozzle, the whole being capable of
being revolved. in the tank and means for revolving each tube independently of the
others.
Eighth. In apparatus for filtering of the construction described the application and
use of a stuffing box and nozzle substantially as described and shown.
Ninth. The application and use of porous tubes for filtering water and other liquids
of the form shewn in Figure 18, substantially as set forth.
Tenth. The improved construction of apparatus for filtering water and other liquids
substantially as described with reference to Figures 17, 18 and 19.
Eleventh. The improved construction of filtering apparatus substantially as described
with reference to Figure 20.
Twelfth. In filtering apparatus of the construction described the application and
use of an air pipe M substantially as described and shown.
Thirteenth. The construction of apparatus for filtering water and other liquids as
shewn.
ROBERT BRUCE.
COLIN C. M. GIBSON.