GB2409654A

GB2409654A - Water filtration system with non-return valve

Info

Publication number: GB2409654A
Application number: GB0426497A
Authority: GB
Inventors: Stephen Halls
Original assignee: Interpet Ltd
Current assignee: Interpet Ltd
Priority date: 2003-12-03
Filing date: 2004-12-03
Publication date: 2005-07-06
Anticipated expiration: 2024-12-03
Also published as: GB0328006D0; GB0426497D0; GB2409654B; WO2005053817A1

Abstract

The system includes a housing 5 having a liquid inlet 8 and outlet 6, filtering material 2, 3, 4 and a non- return valve 9 preventing reverse flow through the inlet, the valve may be gravity actuated and incorporate a flexible valve member. Several sets of filtering material 2, 3, 4 may be provided. The system may be used in aquarium and may be provided with suction means for attaching to the glass of an aquarium.

Description

WATER Fll,TRATION SYS'I'EMS AN[) APPARATUS FIEI,D OF THIN INVE.N'rlON This

invention relates to the filtration of water and particularly hut not exclusively to the filtration of water contained in aquaria.

BACKGROlJNI) TO Tl-IE INVENTION The keeping of fish in aquaria is a wide spread activity and has resulted in many dift'erent shapes and sizes for the aquariums in question, with the sizes ranging from, for example, tanks containing a flew litres ot' water to tanl;s containing several hundreds of litres.

The species of fish kept in such aquaria can be very conveniently divided into three main divisions, namely fresh water fish which do not require water temperatures other than room temperature water, these are kept in so-called cold water tanks, fresh water tropical fish requiring heated water and fish requiring a non fresh water special water environment commonly called marine fish tanks Generally the keeping of any of the above mentioned groups of fish require the installation of lighting facilities t'or illuminating the interior OT' the tank so as to provide for a controlled simulation of'night and day.

In the case of fish requiring water temperatures above room temperature temperature controlled water heating arrangements are required.

Because of the very nature of the environment of fish being housed within what might be called a static water environment it follows that waste materials are being continuously produced by the natural life functions of the tush and are continuously being deposited into the water. Also as a consequence of food particles debris arising from the provision of fish food into the tanks additional contamination trequenily occurs.

I'o achieve and maintain an acceptable (to the fish) overall cleanliness to the water within the tank it is a conventional practice to provide an arrangement whereby the tank water can he filtered in such manner as to remove such waste materials and debris, and as tar as possible any other undesirable contaminants in the tank water, as is necessary to he able to maintain cleanliness of the water.

This filtration requirement is general in that what ever the type of fish involved the requirements t'or good husbandry apply particularly in teens ot'the internal cleanliness of the tank water and content.

Since the need to provide t'or filtration ot' the water used in aquaria is well appreciated and in consequence can be conveniently regarded as a standard aquaria practice many forms oi'tiltration apparatus have been developed. and are known. Such filtration apparatus can conveniently be regarded as t'allinL into two main categories namely internal tillers that are located when in use in the interior ot'the tank and external inters that when in use reside externally of the tank.

In relation to the use ol'either t'orm ot'filter it is generally necessary to produce a flow ot' water through a filtering medium contained in an appropriate housing provided with a 'dirty water inlet, a clean water outlet and a chamber within which the filtering media is housed and conventionally into which filtered material becomes entrained as a consequence of the flow of the water through the filter arrangements.

In practice this water flow is produced conveniently by means of an appropriate electrical pump.

In relation to the known filters it has been noted that in the event that the water flow through the filters is interrupted for what ever reason filtered material that has been drawn into the filtering system can on the cessation ol' wafer flow can move back into the tank and admix with the tam; water.

In practice, the very action of the filter operation tends to concentrate the material whereby on said cessation the concentration amount of debris moved back into the tank tends to the greater per unit volume ot' water than its initial input concentration.

This situation is regarded as being undesirable particularly in situations in which recontamination is regarded as being unacceptable.

OBJEC'I' OF Tl IF INVENTION It is an object of the present invention to provide an aquaria filtration system that reduces on a cessation ol'a filtration water flow the risl; of recontamination ot'the water in the tam;.

] 5 STA'I'EMENTS OF '1'1 IL*. INVENTION Broadly according to a first aspect of the invention there is provided a filtration system in which control means are provided to prevent reverse flow of material having been drawn into a filtration apparatus out prom the filtration apparatus.

A further aspect of the invention provides a filtration system t'or liquids including a housing/container having a liquid inlet and a liquid outlet and containing liquid filtering material, characterized in that liquid flow control means are provided in the liquid inlet path of the system for preventing reverse flow of liquid and any contaminant material contained therein material through the liquid inlet.

A further aspect of the invention provides filtration system for liquids containing particulate material and characterized in that the control means includes valve means interposed in the liquid inlet flow path into the system in such manner that during liquid flow through the system the valve means is maintained in its open to allow liquid flow and in that upon cessation ova liquid flow the valve means automatically moves to a closed state to prevent liquid flow there through, the arrangement being such that the risk of particulate material having, entered the filtration system from discharging by way of the liquid inlet path A t'urther aspect of the invention provides aliquid filtration system l'iltering water of an aquatic environment in which valve means are arranged to at least reduce the risk of material having been caused to enter the filtration system from re-entering the water of the tank on cessation of operation of means causing material to enter the system In a preferred arrangement the l'iltration system is provided in the water flow path ot' a water driven aquaria filtration system and incorporates a valve arrangement which allows water and particulate contaminants to enter the filtration system under the action of a water flow through the system but prevents a return movement oi'the contaminants in the absence of said water flow.

Preferably the valve arrangement comprises a ()nc way gravity activated valve.

2() Conveniently, the valve incorporates a flexible valve member.

In a preferred construction characterized by the system incorporating at least two separate series arranged filter units liquid entering the liquid inlet of the system is caused successively to flow though the filter units to the liquid outlet of the system, and in that a common liquid inlet control valve is provided for the system 2 5 or an liquid inlet control valve is provided for each Jilter unit. - 5-

Wherein the f Itering material provided in the units is of such filtration capacity as to be successively finer contaminated material.

BRIEF DESCRIP'I'ION Ol; TtIE DRAWIN(,S For a better understanding of the invention and to show how to carry the same into effect reference will now be made to the accompanying drawings in which; Figure I is a schematic sectional view of an t'irst embodiment of' an aquaria filtration apparatus; Figure 2 is an enlarged 'see through' view of a part of casing suitable for containing filter material as may be used with the apparatus of Figure 1; Figure 3 is an exploded view of a non- return valve assembly forming part of the apparatus of 1 igure 1; Figure 4 is an exploded view of a further embodiment of the non-return valve assembly; Figure 5 is view ova t'urther emhodiment ol'a valve member for the apparatus ot' 1 5 Figure 1; Figure 5A is section on the line R13 of 1 inure 5 Figure 6 is a side view of an embodiment of a filtration apparatus incorporating the concepts of the invention; and Figure 7 is a part sectional view ot' the interior ot'the apparatus of Figure 6

DETAILED DESCRIPTION OF DRAWINGS

Referring now to Figure 1 the filtration apparatus I schematically shown therein can be regarded as comprising a stack of three filtration modules 2,3 and 4 ol similar construction. In practice these modules would be readily removably housed within a housing not shown in Figure 1.

In the embodiment schematically shown in Figure 1 each such module includes a cylindrical casing 5 open at the top 6 and terminating in an inwardly directed annular Range 7 which in turn connects with the upper rim of a downwards extending: cylinder 8 which in operation provides a water inlet duct. In the I 0 embodiment shown a non-return valve 9 is operationally positioned in the vicinity of the bottom ol the cylinder 8 of each module.

It should be noted that in a further embodiment the several valves are replaced by a single valve at the base of the apparatus, that is in the vicinity of the base of the lowermost module Each module incorporates is the actual filtration material 10. In practice, the filtration material can comprise a mass of fibrous material or a volume of a particulate material collectively presenting a large particulate material surface for reacting with any contaminates that may be contained in water passing through the module in a direction from the inlet to the cylinder 8 to an outlet (not shown in Figure 1) in the vicinity of the top/rim 6 ofthe casing 5. This filter material 10 is conveniently housed in a net/mesh like container 11 that allows easy water flow of water through the filter material 10 whilst facilitating handling of the filter material ID on its insertion and removal from the container 11 A locating element 12 is provided at the base of the filter material container 11, the locating element 12 being enterable into the upper part of the cylinder 8 in such manner as to position the filter container I I with respect to the casing 5. /

In use a flow of water is fed into the lowermost module 2 by way of the cylinder X. 'I'his flow ot'watcr is suf'fcient to open the valve ') to allow contaminated water to enter into the Casio, 5 and to thus enL;a,e with the t'ilterint material 1().

The contaminated water moves through the filtering material 1 () and in the course of which now the contaminate material is collected upon the filtering: material.

The water after having: passed through the fltcrinL; 10 passes into the next adjacent module. This process continues until the water emerges from the upper end of the uppermost module from which it flows into the outlet at the top of' the casing 5.

It will be appreciated that so long as the flow of' wafer is maintained the filter material casings of' each module is subjected to lilt forces whilst the non return valve 9 is maintained in its valve open position.

If the water flow is stopped any lift forces acting: upon the non-return valves 9 of the modules 2,3 and 4 are removed so that the non-retun valves 9 thereof ] 5 automatically move to their closed positions.

For each module the closure ot' the associated non-return valve 9 prevents any of the contaminant material that has previously passed through the valve from dropping; downwards of'the cylinder 8 either back to a module lower in the stack or as in the case ot'the lowermost module 2 back into the tank itself'.

It is convenient to note that in the case of a stack of modules the filtering material can become proLrcssively l'iner in the sense Prom the bottom ot' the stack upwards so that the courser contaminants are extracted in the lowermost module and the finer contaminants from the uppermost module.

Referring now to Figure 2 this illustrates to an enlarged scale detail of a possible 2 5 construction for the casing as will be noted the case includes inwardly projecting axially directed vanes 13 equiangularly spaced around the casing wall 5 together with a spider like t'ormation 14 t'or the base of the casing. This arrangement assists in maintaining the shape of the container Nor the filter material whilst at the same time ensuring even distribution of space t'or the water flows schematically shown by the arrows of Figure I As is indicated in Figure 3 the non-return valve shown therein comprises an annular flexible member 15 i.e., flap type valve, that fits into a cup-like element 16 having a cylindrical wall 17 that is a push tat on to the lower end of a the cylinder 8. The cup like element 16 has a spider t'ormation 18 for its base with I O the central crossover point for the legs of the spider provided with a locating peg 1') for engaging the a central bore 20 of' the flexible member 15 thereby to eft'ectively locate the member 15 in its operational position.

Apertures 21 produced by the shaping ot' the spider formation 18 provide the contaminated water input openings into the interior ol' the cylinder 8 and thus to the filtering material I ().

The upper part ot'Figure 3 very schematically illustrates a possible t'ormation for facilitating the mounting ot'the valve element cup 16 to the the casing 5.

As will be noted the the inner ring 22 of the annular flange 7 is provided with a series of upwardly inclined struts 23 connecting with a central disc 24 which inter alla provides a locating support t'or the filter material container I 1.

Figure 4 illustrates in exploded form a further embodiment of the mounting for the valve element 15. In the proposal of Figure 5 the valve element includes an narrow annular band 26 that is positioned and dimensioned so as to provide a seal between the cup like element 16 and remainder of the unit, and a flap part 27 2 5 which provides the actual valve member.

Referring now to Figures 5 and 5A these Figures illustrate a further embodiment of a flap valve 28 comprising a generally egg shape piece of flexible material 29 having a peripheral rim 30 having a circular cross section. As may be seen from Figure 5 two elongate cut-out regions 31 and 32 are provided in the material in such manner that the central region 33 of the material is connected to the remainder of the material by two regions 33 immediately opposite to each other.

This construction forms two regions 34 35 tact as flap valves that in practice can combine to form a double acting flap valve Referring now to Figures 6 and 7 the aquaria filter shown therein includes an outer housing 36 mounting a suction type attachment means 37 whereby the filter can readily be mounted within an aquarium to the glass thereof A grill like Formation 38 is provided at the lower regions ol the filter to serve as the water inlet to the filter. A filter outlet 39 intended for connection to a water circulating system (not shown) is provided at the top ot the lilts.

This outlet is provided in a cover assembly 40 which is removable to allow access to the interior of the housing 36. Arrangements not shown in detail are provided for controlling the water throughput through the filter. This facility is very schematically represented by the lever 41 and plus and minus signs indicating movement direction of the lever 41 to increase or decrease water flows.

As schematically shown in Figure 7 a stack of three filter modules 2 3 and 4 is provided within the housing 36. It will be appreciated that the three separate modules could be replaced by a single module having for example three successively diminishing finer grades of filter material.

In the Figure 6 and 7 arrangement a single control valve 15 is provided at the base 2 5 of housing. The element is so positioned that all water entering into the housing has to pass through the control valve 15. A valve element such as shown in Figures 5 and 5A is provided at the base of the housing, downstream of the water inlet to the filter. The internal structure of the housing provides a seating for the filter element making use of the peripheral rim on the element to ensure that the element correctly seats in its required operational position.

To operation a flow of contaminated water pushes the valve parts 34 and 25 to their valve open positions. So long as the flow continues water will enter into the housing to the outlet 39 by way of the filter material modules 2,3 and 4. On cessation of the water flow the resulting drop of pressure acting on the valve parts 34,35 that holds them in their open positions ceases whereby the parts 34, 25 return to the valve closed settings thereby preventing any back flow through the filter during any subsequent handling such as the removal of the filter from the aquarium.

Whilst a single valve has been considered in relation to l;igures 6 and 7 a multi-valve arrangement for example similar to that indicated in the F igure 1 could be utilised.

It will be appreciated that whilst flap type valves have been illustrated other fomms of valve may be used subject to the requirement that the valves will automatically close upon cessation of water flow through the filter.

Claims

CLAIMS.

1. A filtration system for liquids including a housing/container (5, 36) having a liquid inlet and a liquid outlet and containing liquid filtering material, characterized in that liquid flow control means (9, 15) are provided in the liquid inlet path of the system for preventing reverse flow of liquid and any contaminant material contained therein material through the liquid inlet.

2. A liquid filtration system filtering water of an aquatic environment in which valve means (9,15) are arranged to at least reduce the risk of material having been caused to enter the filtration system trom reentering the water of the aquatic lo environment on cessation of operation ot means causing material to enter the system 3. A liquid filtration system for liquids as claimed in claim I or 2, and characterized in that the control means includes valve (9, 15, 26/27, 2X) interposed in the liquid inlet flow path to the system in such manner that during 1 5 liquid flow through the system the valve means (9, 15, 26/27, 28) is maintained in its valve setting open to allow liquid flow through the system from inlet to outlet, and in that upon cessation of a liquid flow the valve means automatically moves to a closed setting to prevent liquid discharge from liquid inlet, the arrangement being such that the risk of liquid and any contaminant material having entered the filtration system is prevented from discharging by way ofthe liquid inlet path 4. A liquid filtration system as claimed in claim 1,2 or 3, characterized in that the filtration system is provided in the water flow path of a water driven aquaria filtration system in that the control means (9,15) incorporates a valve arrangement which allows water and particulate contaminants to enter the filtration system under the action of force produced by a water flow through the system but prevents a return movement of the contaminants in the absence of said water flow. - 12

A liquid filtration system as claimed n any one of claims I to 4, and characterized in that the control valve means incorporates a one way gravity actuated valve (9,15,26/27,28) 6. A liquid filtration system, as claimed in claim 5, and characterized in that the the valve incorporates a flexible valve member (15, 25/27,28).

7. A liquid filtration system as claimed in any one of claims I to 6, and characterized in that the system incorporates at least one liquid filtering module (2,3,4) including a housing (5, 26) tor filtering material, a contaminated liquid inlet region (8, 38,) to the housing (5,36), a filtered liquid outlet region (8,39) and an valve (9, 15, 26/27, 28) for controlling the ingress of contaminated liquid into the container, the valve being adapted automatically to open and remain open whilst liquid is passing through the container and automatically to close upon cessation of liquid flow into the container.

8. A liquid filtration system as claimed in any one of the preceding claims I to 7, and characterized in that when the system incorporates at least two separate filter units (2,3,4) they are located liquid wise in series whereby liquid entering the housing is caused successively to flow through the filter units to the liquid out let of the system (8,39).

9. A liquid filtration system as claimed in claim 2, and claims 3 to 8 as appendant to claim 2, and characterized in that the housing (36) is provided with suction means (27) for mounting the housing to the glass ot an aquarium.

10. A liquid filtration system, constructed and arranged to operate substantially as hereinbefore described with reference to igures 1 to 5, and Figures 6 and 7 of the accompanying drawings