KRANSELL & WENNBORG AB (P.O. Box 27834 S- Stockholm, 115 93, SE)
| 1. | An aquarium filter, comprising: a filter body (12) made of a material with a fil tering function and adapted to be placed in an aquarium (10) so that said filter body divides the aquarium volume into a first (4) and a second (6) compartment, wherein the filter body is arranged to cooperate with a pump (14) arranged to displace water from the first compartment, through the filter body (12) and into the second compartment (6) and means (16) for returning filtered water in the second compartment to the first compartment, c h a r a c t e r i z e d i n that the filter body (12) is selfsupporting, the filter body (12) has a shape as to cover essentially the entire back wall of the aquarium, the filter body (12) is so shaped as to form a natural decoration of the aquarium, and the surface of the filter body visible to a viewer of the aquarium is given a texture resembling natu ral material. |
| 2. | An aquarium filter according to claim 1, wherein the filter body (12) is made of opencelled foamed plastic material. |
| 3. | An aquarium filter according to claim 1 or 2, wherein the filter body (12) is made of polyurethane. |
| 4. | An aquarium filter according to any of claims 13, wherein the filter body (12) is adapted to be used as a platform for vegetation. |
| 5. | An aquarium filter arrangement, comprising: a filter body (12) made of a material with a fil tering function and adapted to be placed in an aquarium (10) so that said filter body divides the aquarium volume into a first (4) and a second (6) compartment, a pump (14) arranged to displace water from the first compartment, through the filter body (12) and into the second compartment (6), and means (16) for returning filtered water in the second compartment to the first compartment, c h a r a c t e r i z e d i n that the filter body (12) is selfsupporting, the filter body (12) has a shape as to cover essentially the entire back wall of the aquarium, the filter body (12) is so shaped as to form a natural decoration of the aquarium, and the surface of the filter body visible to a viewer of the aquarium is given a texture resembling natu ral material. |
| 6. | A method of manufacturing an aquarium filter, comprising the following steps: preparing a mixture of polyurethane or other suit able mixture for creating an opencelled foamed plastic material, applying said mixture to a mould functioning like an endless conveyor belt and with a bottom inner sur face giving a shape resembling natural material, bringing the mixture to set into filter material elements of a fixed width, and cutting the filter material elements to desired lengths to form filter bodies. |
BACKGROUND When animals, such as fish, are to be maintained in an aquarium, the quality of the water in the aquarium must be maintained at a certain level. Therefore, there is often provided a filter arrangement in some way con- nected to the aquarium, the function of which filter arrangement is to filter the water in the aquarium.
There are several types of aquarium filters, of which can be mentioned mechanical filter in which waste mate- rial is physically trapped. These filters use filter material in the form of e. g. gravel, synthetic resin fibres or open-cell foam, e. g. polyurethane. With the exception of undergravel type of filters, a common fea- ture of all these mechanical filters is that they are difficult to place in the aquarium in an aesthetically satisfying way.
The US patent publication (Preston) discloses an aquarium filter assembly made of an open celled foam material. The filter body substantially defines a closed cavity and a passageway extends through the open celled foam material into the cavity. The aquarium fil- ter assembly includes a means for mounting the filter
body within the aquarium but spaced from interior sur- faces thereof to permit unobstructed flow through sub- stantially the entire filter body. This filter is very difficult to place in an aesthetically satisfying way.
The US patent publication 4,699,829 (Willinger) dis- closes ornamental artificial foliage provided with a rough, granular surface texture over and above that normally required for the aesthetic appearance of the foliage. The object of the provision of a rough texture is to aid in the propagation of bacteria for biological filtration of the aquarium water and to improve the life-like nature of the foliage. The filtering function is entirely bacterial and no pump arrangement is dis- closed.
The US patent publication 3,815,547 (Willinger et al.) discloses a filtering device for use with an aquarium.
The filtering device is arranged in a generally verti- cal plane in the aquarium to form first and second com- partments. However, the filtering material is contained in a supporting frame provided with holes. This solu- tion creates several disadvantages, of which can be mentioned a reduced active filtering area and a less pleasing appearance for a viewer of the aquarium.
The US patent publication 5,207,900 (Findell) discloses a single-piece, absorbent sponge acting as the main filtering element for an aquarium filter. The filter is adapted to be placed in an unobtrusive way in the aquarium, e. g., in the back corner. This filter has a comparatively reduced active filtering area and does not contribute to the appearance of the aquarium interior.
OBJECT OF THE INVENTION An object of the present invention is to provide an aquarium filter, which combines an improved filtering function with a more aesthetic appearance and with an easy installation, compared to known filter arrange- ments.
SUMMARY OF THE INVENTION The invention is based on the realisation that a self- supporting artificial decoration placed in an aquarium can be given a filtering function by giving the decora- tion material suitable properties.
According to a first aspect of the invention there is provided an aquarium filter as defined in claim 1.
According to a second aspect of the invention there is provided an aquarium filter as defined in claim 5.
According to a third aspect of the invention there is provided a method of manufacturing an aquarium filter assembly as defined in claim 6.
Further preferred embodiments are defined by the de- pendent claims.
With the aquarium filter, the arrangement and the method according to the invention, the above stated object is attained. Thus, there is provided a filter with has a large filtering capacity, which is easy to assemble and clean and that has a pleasing appearance.
BRIEF DESCRIPTION OF DRAWINGS The invention is now described, by way of example, with reference to the accompanying drawings, in which:
Fig. 1 is a top view of a filter arrangement according to a first embodiment of the invention; Fig. 2 is a front view of the filter arrangement shown in fig. 1; and Fig. 3 is a top sectional view of filter arrangements according to further embodiments of the invention.
DETAILED DESCRIPTION OF THE INVENTION In the following, a detailed description of preferred embodiments of the invention will be given. In fig. 1 is shown a top view of a filter arrangement, generally designated 10 placed in an aquarium 2 filled with water. The filter arrangement 10 comprises a filter body 12, a pump 14 and a pipe 16 connected to the pump and arranged through the filter body 12. Thus, the fil- ter body 12 divides the aquarium into two compartments: one front compartment 4 in front of the filter body and one back compartment 6 behind the filter body.
In fig. 2, a front view of the aquarium in fig. 1 is shown. It is seen that the only aesthetic disturbance is the pipe 16 ending in front of the filter body 12.
However, also this could be avoided by having the pipe 16 end just before the front surface of the body 12, i. e., by making the hole in the body arranged for the pipe 16 stop before it penetrates the front surface.
In operation, water is circulated from the front com- partment 4, through the filter body 12 and to the back compartment 6 and back again through the pump 14 and the pipe 16 to the front compartment as indicated by the arrows in fig. 1. In that way, the entire filter
body 12 functions to filter the water flowing through it.
In order to ensure a relatively uniform flow of water through the filter body and that no water leaks from the front compartment to the back compartment, it is important that the body abuts against the walls of the aquarium. Also, the filter body 12 is placed tightly against the bottom material of the aquarium and has a sufficient height to extend above the water surface.
The filter body 12 is made of some suitable filter ma- terial, such as polyurethane. An important character- istic of the filter material is that it is self-sup- porting, i. e., the filter body needs no extra support in order to function properly. In order to give the filter body an aesthetically appealing surface, it is treated either mechanically or chemically. Also, the filter body can be moulded in a cast wherein its sur- face is given a natural appearance. In that way, the filter body 12 also functions as a background of the aquarium, thus replacing the kind of background conven- tionally found in aquariums. The surface can be given a structure resembling any natural configuration, such as stone, tree roots, organic underwater surface etc.
An advantage with the filter arrangement according to the invention is that it is easy to clean. The pipe 16 is simply disconnected from the pump 14, the filter body 12 is removed from the aquarium, rinsed by means of water from a water tap and returned into place in the aquarium. Because the preferred filter material, polyurethane, is flexible, it is simply slightly com- pressed when removed from and returned to the tank, and
in the latter case, the filter body expands, thus pressing against the sidewalls of the aquarium. During this cleaning operation, the pump 14 can remain in the aquarium if so desired.
Alternative embodiments of a filter arrangement are shown in fig. 3, which is a top sectional view of an aquarium similar to fig. 1. In the leftmost embodiment in fig. 3, a pump 20 is placed externally of the aquar- ium. There is provided a pipe system 22 bringing the water from the back compartment 24 of a filter body 26 to the pump 20 and a pipe 28 leading from the pump and to the front compartment 4'.
A difference from the embodiment shown in fig. 1 is that the filter body 26 does not cover the entire aquarium surface on which it is mounted. Instead, it is placed in one corner of the aquarium. The filter body must still be placed close to the walls to prevent un- desired leakage of water.
This embodiment could be useful e. g. when a larger vol- ume of water is desired for the fish etc. living in the front compartment of the aquarium.
A filter arrangement according to the invention is not restricted to placement along the entire back wall or a corner thereof. In fig. 3 is also shown a filter body 30 with an interior compartment 32 in which a pump 34 and a pipe 36 attached thereto are placed. This filter arrangement is placed along the back wall of the aquar- ium and at a distance from the corners thereof. How- ever, this configuration works in the same way as the previously mentioned.
In fig. 3 is also shown a filter body 40 with an inte- rior compartment 42 with a pump 44 and a pipe 46. This filter arrangement is intended for placement at a dis- tance from the walls. The filter body 40 must thus cover the compartment 42 on all sides except the under- side.
Besides being aesthetically appealing, the filter ar- rangement according to the invention has also the advantage, that a larger filter surface can be used, especially in the last embodiment, thus improving the flowing through the filter body and thereby the filter- ing function. When conventional internal aquarium fil- ters are limited to a small part of the aquarium space, because otherwise they would occupy too much space for the fish, vegetation, background etc., the area of e. g. the entire back wall can be used by the filter accord- ing to the invention.
Another advantage with the filter arrangement according to the present invention is that it can be used as a platform for vegetation. Plants can be placed with their stalks in the filter body, whereby an even more natural and appealing background is achieved.
The described aquarium filter body is easy to adapt to large-scale production. According to a preferred method, the filter is manufactured in the following way. Initially, a mixture of polyurethane or other suitable mixture for creating an open-celled foamed plastic material is prepared. The mixture is then poured or sprayed into a mould functioning like a con- veyor belt, i. e., essentially being an endless mould.
The mould is provided with a bottom shaped so as to
give the resulting moulded element a natural looking texture, such as a surface resembling stones or tree roots.
In that way, long elements of filter material are pro- duced with a fixed width. The filter material is then cut into desired lengths to form the final filter bodies.
The alternative embodiment of a filter body 26,30 shown in figure 3 is manufactured in the following way.
A workpiece of filter material is shaped so as to re- semble a natural configuration. Thereafter, a compart- ment is created in the workpiece for housing an aquar- ium filter pump. In order to complete the assembly, a pump is placed in the compartment and a pipe is con- nected to the pump. This pipe is arranged through the filter material.
Preferred embodiments of a filter and a filter arrangement according to the invention have been described. A person skilled in the art realises that these can be varied in several ways.
The pump and pipes can of course be placed anywhere in the back compartment or externally, as long as water is circulated in a satisfying way through the filter body 12.
The filter bodies defining an interior compartment can either be open-topped, as suggested in the embodiment shown in fig. 1, or be closed-topped. The latter alter- native must of course be used when the filter body does not extend all the way from the bottom of the aquarium to the water surface.
Although an aquarium environment has been described, it is understood that the inventive filter arrangement is also applicable to similar environments, such as vivar- iums, outdoor pools etc.
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