The object of this invention is a water filter for aquarium, in particular the one used in external water filtration systems for fish farming and in waterholes.

The prior art external filters for purification of water in an aquarium and waterhole are connected to a dedicated water circuit by means of conduits that are positioned within water inlet and water outlet connecting ports secured in the filter cover. As a rule such filters are separate, i.e. external, components of aquarium or waterhole equipment, and positioned close to the reservoir in which it operates.

Contaminated water fed into the filter passes a sequence of filtration stages and types in the course of which, suitably to the filtration cartridge or means used, mechanical, biological and chemical filtration may be performed.

Due to the specific nature and effectiveness of water purification performed, it is preferable to perform mechanical filtration first - regardless whether as an exclusive or initial step of purification from mechanical impurities. The external filter draws water from an aquarium along with particulate wastes in it, including the organic ones that cause very rapid clogging of the filtration media and impairing effectiveness of the water purification process consequently. The related necessity for frequent changes of filtration cartridges within the entire device causes a need for new constructional solutions to enable comfortable and easy access to the individual water purification levels.

Document EP 2356900 Bl discloses an external filter for purifying water in aquarium, comprising chamber of mechanical filtration, constituting a part of water purification, extending vertically inside the housing of the filter, and separated from the main filtration unit. Within the mentioned mechanical filtration chamber a first step of water purification is carried out, to separate particles or mechanical debris therefrom. The mechanical debris filtered out in the chamber is then conveyed to a removable drawer at the bottom of the filter. Access to the mechanical filtration chamber and the main filtration unit within the filter is possible by removing a filter cover attached to its housing by means of a snap-fit connection.

Document EP 1832164 Bl discloses an external filter for an aquarium with an additional level of a roughing filter positioned at the upper part of the device, just beneath the cover. The main filtration chamber is positioned inside the housing in its central part and below the roughing filter. Water fed to the filter is conveyed downwards within the device and, first of all, passes through the roughing filtration level, and then upwards to an outlet provided in the cover - it flows through subsequent filtration levels in the main chamber of the filter container. Access to the individual filtration levels is possible by removing the cover positioned on the device housing.

In the presented solutions access to filtration levels is possible exclusively upon removal of the entire cover which entails a necessity to remove water circulation conduits or at least the water inlet and outlet ports arranged in the cover.

It is the object of this invention to propose a better construction of the external water filter doe aquariums, with an easier access to the individual filtration levels, in particular a roughing filtration level, without the hitherto required disassembling of the filter cover or components comprised by it.

Water filter for an aquarium according to the invention comprises a housing in a form of an upwardly open container of a canister type, with side walls and filtration cartridges housed therein, as well as a cover attached to the housing and accommodating a priming arrangement and connection ports of water inlet and water outlet arrangements, where the water inlet and water outlet arrangements are provided with valves. The water filter is characterized in that in the cover a roughing filter chamber is formed that is covered at the top by a lid arranged within the cover.

Preferably, the cover body encompasses a cover jacket and cover side walls with a rim formed on their periphery, where in one part of the cover body a priming arrangement and water inlet and water outlet arrangements are positioned, and in the other part a roughing filter chamber with a filtration cartridge is formed.

Preferably, the lid is suspended in the cover by means of hinges that are fastened in the head surface of the cover jacket.

Preferably, the roughing filter chamber is connected to the water inlet arrangement by an inlet opening of the chamber, formed in its rear wall, and has a chamber outlet opening which is surrounded by the jacket, where the height of the jacket is not less than the height of the filtration cartridge in the roughing filter chamber.

Preferably, inside the roughing filter chamber a removable container for a filtration cartridge is positioned, which in its rear wall has an inlet opening of the container whose positioning corresponds to the inlet opening of the chamber, and in the top wall it has an outlet opening of the container which is positioned around the entrance of the jacket that surrounds the outlet opening of the chamber.

Also preferably, the inlet opening of the container is covered from the inside of the container by a pivotable flap suspended in its rear wall.

According to a preferable solution, the cover is fastened to the housing by means of a snap-fit connection.

Preferably, the snap-fit connection comprises first closing clamp and second closing clamp, articulated in the side walls of the housing and snap-fit on the rim of the cover. Preferably, the second closing clamp is suspended on rotatable arms, at both sides around each first closing clamp, and in the closed position of the closing clamps, the first closing clamp is covered by the second closing clamp.

Also preferably, the first closing clamp and the second closing clamp are terminated in hook-shaped ends.

Further preferably, on each of the side walls of the housing an identical pattern of first closing clamps and second closing clamps is provided.

Preferably, the cover is attached to the housing by means of three second closing clamps, seated on the respective adjacent side walls of the housing.

Further preferably, the water inlet arrangement has an inlet ball valve and at least one check valve.

Preferably, the inlet ball valve is at least a double-seat valve.

Preferably, the inlet ball valve is a double-seat valve.

Also preferably, it has two check valves that are positioned downstream the inlet valve and upstream the roughing filter chamber.

Preferably, the check valves are constituted by a first closing flap and a second closing flap.

Additionally preferably, the water inlet arrangement has an outlet ball valve.

Preferably then, the outlet ball valve is at least a double-seat valve.

Preferably, the outlet ball valve is a double-seat valve.

Moreover, in a preferable solution filtration cartridges are arranged in containers.

The object of the invention is shown in embodiments in the drawing where: fig. 1 shows a perspective view of a water filter for an aquarium according to this invention, fig. 2 shows an exploded view of a housing of a water filter for an aquarium according to the invention, fig. 3 shows a partial and simplified cross-sectional view illustrating water inlet and water outlet arrangements, fig. 4 shows a cross-sectional view illustrating a water inlet arrangement and a roughing filter chamber, with connection detached ports, fig. 5 shows a cross-sectional view illustrating a water outlet arrangement, fig. 6 shows a perspective view of a filter cover, fig. 7 shows a perspective view of a filter cover with an open lid, fig. 8 shows a perspective view from the top of a filter, in an open position of the lid, illustrating a roughing filter chamber, fig. 9 shows securing of a cover in a closed position of the lid, and fig. 10 shows a view analogous as in fig. 8, in an open lid position.

According to fig. 1, a water filter 1 for an aquarium comprises a housing 2 and a lid 3 secured thereto. The housing 2 is formed as a vertical, open at its top container of a canister type, with side walls 5, seated in a base 4. Inside the housing 2 filtration cartridges are arranged that may be constituted by standard filtration media, such as for example activated carbon or foam cartridges. Filtration cartridges are arranges in containers 2’, which as shown in figs. 2, 4 or 5, are arranged inside the housing 2 one above another, and form a vertical set of sequenced levels with filtration cartridges.

The cover 3 is secured to the housing 2 removably and - as presented in fig. 6 - its body includes a jacket 6 and side walls 7 with a rim 8 formed on their perimeter. During mounting the cover 3 in the housing 2, the body of the cover 3 - in the section below the rim 8 - is seated inside the side walls 5 of the housing 2 so that the mentioned section of the body of the rim 3 remains invisible during operation of the filter 1. According to the embodiment shown, in one part of the body of the cover 3 connection ports 9’, 10’ are arranged for water inlet 9 and water outlet 10 arrangements respectively, positioned within the cover 3, as well as a piston 11 of a priming arrangement. In a second part of the body of the cover 3 a chamber of a roughing filter 12 is formed, intended for effecting roughening mechanical filtration therein.

Fig. 3 shows a partial and simplified cross-sectional view of the filter 1 illustrating the water inlet 9 and the water outlet 10 arrangements. In the cover 3 removable connection ports 9’, 10’ are secured - for the water inlet 9 and the water outlet 10 arrangements, respectively. To said ports 9’, 10’ a water draining conduit 910’ and a water supply conduit 910” are connectable from and to the reservoir in a form of an aquarium or a water hole (not show) in which the filter 1 operates). The connection ports 9’, 10’ are connectable to the water inlet 9 and water outlet 10 arrangements to form an inlet valve 9” and an outlet valve 10”, respectively, which according to the embodiment are double-seated ball valves.

Construction of the water inlet 9 arrangement is shown in fig. 4, according to which, downstream the double-seated ball valve 9”, a water inlet 9 arrangement - cooperating with a priming arrangement (not shown), provided with two check valves arranged in order to prevent water backflow during priming the filter 1. The check valves are constituted by a first closing flap 91 and a second closing flap 92. The use of check valves 91 and 92 prevents water backflow during priming the filter 1 and thus enables guiding water from an aquarium or a waterhole directly to the chamber of the roughing filter 12, connected to the water inlet arrangement, and then to the subsequent filtration cartridges provided in the housing 2 of the filter 1.

As presented in fig. 5, water finally filtered inside the housing 2 is drawn by a pump 102, driven by a motor 101 and directed to a water outlet 10 arrangement terminated in a connection port 10’, and then it is guided through a draining conduit 910” to a reservoir (not shown). The chamber of the roughing filter 12 is externally covered with an openable lid 13 which - in its closed position - forms a continuous body of the jacket 6 of the cover 3. The lid 13 has an top wall 131, side walls 132 and a front wall 133. According to the embodiment shown in figs. 6-8, the lid 13 is pivotably suspended on hinges 14 which are secured on the head surface of the jacket 6 of the cover 3. The lid 13 is openable by means of a handle 15 formed in its front wall 133.

Apart from the handle 15 of the lid 13, the cover 3 is also provided with handles 16, to enable its comfortable and easy, for the user, removal from the housing 2 of the filter 1. According to an embodiment, the cover 3 has two handles 16, positioned on the side walls 7 of the cover 3, perpendicularly to the surface on which the handle 15 of the lid 13 is positioned.

According to fig. 8, the chamber of the roughing filter 12 is connected to the arrangement of the water inlet 9 by means of an outlet opening 121 formed in its wall, and has an outlet opening 122 to guide water further to the inside of the housing 2 and the filtration cartridges provided therein. The outlet opening of the chamber 122 is surrounded by a jacket 122’ the height of which is not less than the height of the filtration cartridge inside the chamber of the roughing filter 12.

In the chamber of the roughing filter 12 a removable container 120 for the filtration cartridge is arranged. The container 120 for the filtration cartridge, in its rear wall, has an outlet opening 1201, corresponding to the inlet opening 121 of the chamber of the roughing filter 12. At the container 120 positioned in the chamber of the roughing filter 12, the positions of the inlet opening 1201 of the container 120 and the inlet opening 121 of the chamber 12 overlap to form a water inlet 9 arrangement with the chamber of the roughing filter 12. In particular as shown in fig. 4, the inlet opening 1201 of the container 120 is covered from the inside of the container 120 by a pivotable flap 123 suspended in its rear wall (as shown in fig.4). The flap 123 is used to prevent water entering the chamber of the roughing filter 12 w during withdrawal therefrom of the container 120 for the filtration cartridge.

The container 120 for the filtration cartridge additionally has, formed its top wall, an outlet opening 1202, which - in the position of the container 120 placed in the chamber of the roughing filter 12 - becomes coupled to the entrance of the jacket 122’ that surrounds the outlet opening 122 of the chamber 12.

According to the embodiment shown, the container 120 for the filtration cartridge has, formed in its top wall, openings 124 that enable free and comfortable for the user removing of the container 120 from the chamber of the roughing filter 12. At the same time, on the inner side of the top wall 131 of the lid 13 pressing elements 134 are formed that - with the lid 13 closed - press, through the openings 124, the filtration cartridge (not shown), intended to be placed in the container 120 for the filtration cartridge.

As shown in figs. 9 and 10, the cover 3 is secured to the housing 2 by means of a first closing clamp 17 and a second closing clamp 18, snapped on a rim 8 of the cover 3. The first 17 and second 18 closing clamps are seated in the side walls 5 of the housing 2 by means of articulation joints 19 - an exemplary arrangement thereof is shown in an exploded view in fig. 2.

The first closing clamp 17 with a hook terminating end 17’ is seated on the side wall 5 of the housing 2, substantially in a position corresponding to a half of the height of the side wall 5 and below its upper edge. On both sides around the first closing clamp 17, on the side wall 5 of the housing 2, the second closing clamp 18 is hingedly attached.

The second closing clamp 18 is formed in a form of a profiled plate with hook shaped terminating ends 18’. The second closing clamp 18 is rotationally suspended on first ends 180’ of a first arm 181 and a second arm 182. Second ends 180” of the first 181 and second 182 arms are suspended rotationally in articulated joints 19. In the closed position of the two closing clamps 17, 18 the first closing clamp 17 remains covered by the second closing clamp 18 extending thereabove.

According to the commented embodiment of the water filter 1 for an aquarium, on each of the side walls 5 of the housing 2 an identical pattern of the first 17 and second 18 closing clamps is provided. This solution provides freedom for positioning, as to orientation, of the seating of the cover 3 in the housing 2, i.e. regardless of the positioning of the arrangements of the inlet 9 and outlet 10 and, in particular, the chamber of the roughing filter 12.

As shown in figs. 9 and 10, attachment of the cover 3 to the housing 2 is ensured by the first closing clamp 17 and a second closing clamp 18 positioned on each of the side walls 5 of the housing 2. The snap-fit connection is made as a result of intermeshing of the hook-shaped terminal ends 17’, 18’ of the closing clamps, correspondingly the first ones 17 and the second ones 18, with tongues 20 formed within the region of the rim 8 of the cover 3.

As regards the lid 13, its front wall 133 is attached to the housing 2 by means of the entire second closing clamp 18, seated on the respective side wall 5 of the housing 2. Attachment of the side walls 132 of the lid 13 is in turn ensured by snap-fit intermeshing effected solely by the closest - relative to the surface of the front wall 133 lid 13 - hook shaped terminating end 18’ of the second closing clamp 18, secured on the respective side wall 5 of the housing 2.

Release of the respective second closing clamps 18 enables opening of the lid 13, while maintaining attachment of the cover 3, provided by closed first closing clamps 17 and possibly the remaining non-released second closing clamp 18, positioned at the rear part of the filter 1. As regards the lid 13, the catches 20 to be intermeshed with the hook shaped terminal ends 18’ of the second closing clamps 18 that secure the lid 13, are positioned at the lower edges of the walls 132, 133 of the lid 13. The described herein solution for securing the lid 13 provides for a possibility of free access to the chamber of the roughing filter 12 positioned within the cover 3, without any necessity to remove the cover 3.

It should be clear that the subject invention is not limited to the above presented embodiment and that diverse modifications and developments thereof are possible within the scope of the enclosed patent claims, without going beyond the scope of the basic idea of the invention.