HANG ON BACK FILTERING UNIT FOR AQUARIUM TANK

Abstract

A filtering unit (1) for aquariums of the hang on back type comprising: a housing (6); a suction pipe (2) provided with a lower inlet (3); and a pump (5) integral with said housing (6) and configured to determine a water circulation through a recirculation path extended inside the filtering unit (1) between said inlet (3) and said outlet mouth (4), wherein a non-return valve (10) is advantageously provided upstream of the pump (5) to maintain a water volume necessary for priming the pump (5) itself.

Claims

1. A filtering unit for aquariums comprising: a housing comprising at least one filter therein and provided with an upper outlet mouth; a suction pipe connected with a lower inlet; and a pump integral with said housing and configured to determine a water circulation through a recirculation path extended inside the filtering unit between said inlet and said outlet mouth, said recirculation path being intercepted by said at least one filter; wherein said filtering unit is of the hang on back type, that is it is arranged to be hung on the wall of an aquarium tank with at least part of said housing placed outside the aquarium tank, said suction pipe drawing inside a water volume of the aquarium tank and said outlet mouth opening above said water volume; the filtering unit further comprising a non-return valve provided along said recirculation path upstream of said pump, said non-return valve allowing the passage of water from the inlet to the pump and preventing the return of water in the opposite direction.

2. The filtering unit according to claim 1, wherein said non-return valve comprises a seat and a shutter body, said shutter body being free to move within an ascending segment of the recirculation path above said seat.

3. The filtering unit according to claim 2, wherein said ascending segment is a portion of the suction pipe.

4. The filtering unit according to claim 3, wherein said seat is defined by a local narrowing of the suction pipe.

5. The filtering unit according to of claim 3, wherein the suction pipe, at an upper end of said ascending segment in which the shutter body is free to slide, has a recess for housing the shutter body during operation of the filtering unit.

6. The filtering unit according to claim 2, wherein said shutter body is a sphere.

7. The filtering unit according to claim 2, wherein said shutter body has a specific weight lower than the one of water.

8. The filtering unit according to claim 1, wherein the non-return valve is housed in an inlet body which is connected upstream to the suction pipe.

9. The filtering unit according to claim 8, wherein the inlet body, at least at a portion housing the non-return valve, has a diameter larger than the diameter of the suction pipe.

10. The filtering unit according to claim 8, wherein the non-return valve comprises a seat and a shutter body both housed within a cavity of the inlet body, said shutter body being vertically movable along an inlet body axis.

11. The filtering unit according to claim 10, wherein the inlet body axis is offset from a longitudinal axis of the suction pipe.

12. The filtering unit according to claim 10, wherein the inlet body comprises a base element and a cover, a disk-shaped insert being held between the base element and the cover, the disk-shaped element comprising a shaped lip which defines the seat of the non-return valve.

13. The filtering unit according to claim 8, wherein the inlet body has radial ribs projecting inwardly within the cavity to guide the shutter body along the inlet body axis.

14. The filtering unit according to claim 2, wherein the shutter body comprises a lower convex head adapted to abut on the seat and an open upper end.

15. The filtering unit according to claim 14, wherein said shutter body comprises an upper shaft opposed to the convex head, the upper shaft being adapted to engage with a vertical guide pin integral with a housing of the non-return valve.

16. The filtering unit according to claim 1, further comprising a pre-filter upstream the lower inlet, the pre-filter being a foam body.

17. The filtering unit according to claim 16, wherein said foam body has a density comprised between 5 and 20 PPI.

18. The filtering unit according to claim 16, wherein said pre-filter has a diameter comprised between 3 and 7 cm.

19. The filtering unit according to claim 16, wherein the value obtained by multiplying the density of the foam body expressed in PPI and the diameter of the pre-filter expressed in cm is between 25 and 75.

20. The filtering unit according to claim 16, wherein said pre-filter is a solid foam body with longitudinal cuts crossing along an axis of the pre-filter, the lower inlet being wedged within the longitudinal cuts in order to mount the pre-filter therearound.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0047] FIG. 1 shows a perspective view of a filtering unit according to a first embodiment of the present invention;

[0048] FIG. 2 shows a side view, sectioned along the suction pipe, of the filtering unit of FIG. 1 in an operating configuration, with water flow sucked according to the direction identified by the arrow S;

[0049] FIG. 3 shows a side view, sectioned along the suction pipe, of the filtering unit of FIG. 1 in an off state of the pump, wherein the non-return valve prevents the flow return according to the direction identified by the arrow B;

[0050] FIG. 4 shows an exploded perspective view of the suction pipe of the filtering unit of FIG. 1;

[0051] FIG. 5 shows a perspective view of a filtering unit according to a second embodiment of the present invention;

[0052] FIG. 6 shows a side view, sectioned along the suction pipe, of the filtering unit of FIG. 5 in an operating configuration, with water flow sucked according to the direction identified by the arrow S;

[0053] FIG. 7 shows a side view, sectioned along the suction pipe, of the filtering unit of FIG. 5 in an off state of the pump, wherein the non-return valve prevents the flow return according to the direction identified by the arrow B;

[0054] FIG. 8 shows an enlarged detail of the inlet body of filtering unit shown in the side view of FIG. 6;

[0055] FIG. 9 shows an exploded perspective view of the inlet body of FIG. 8;

[0056] FIG. 10 shows a perspective view of a filtering unit according to a third embodiment of the present invention;

[0057] FIG. 11 shows a side view, sectioned along the suction pipe, of the filtering unit of FIG. 10 in an operating configuration, with water flow sucked according to the direction identified by the arrow S;

[0058] FIG. 12 shows a side view, sectioned along the suction pipe, of the filtering unit of FIG. 5 in an off state of the pump, wherein the non-return valve prevents the flow return according to the direction identified by the arrow B;

[0059] FIG. 13 shows an enlarged detail of the inlet body of filtering unit shown in the side view of FIG. 11;

[0060] FIG. 14 shows an exploded perspective view of the inlet body of FIG. 13;

[0061] FIG. 15 shows a sectioned side view of an inlet body of a filtering unit according to a fourth embodiment of the present invention;

[0062] FIG. 16 shows an exploded perspective view of the inlet body of FIG. 15;

[0063] FIG. 17 shows a sectioned side view of an inlet body of a filtering unit according to a fifth embodiment of the present invention;

[0064] FIG. 18 shows an exploded perspective view of the inlet body of FIG. 17;

[0065] FIG. 19 shows a sectioned side view of an inlet body of a filtering unit according to a sixth embodiment of the present invention;

[0066] FIG. 20 shows an exploded perspective view of the inlet body of FIG. 19;

[0067] FIG. 21 shows a sectioned side view of an inlet body of a filtering unit according to a seventh embodiment of the present invention;

[0068] FIG. 22 shows an exploded perspective view of the inlet body of FIG. 21.

DETAILED DESCRIPTION

[0069] With reference to the enclosed FIGS. 1-3, reference number 1 generically identifies a first embodiment of a filtering unit according to the present invention.

[0070] In particular, a filtering unit for domestic aquariums of the so-called hang on back type is described, namely, designed to be hung astride above the rear wall of an aquarium tank (not illustrated).

[0071] The filtering unit 1 is represented in the figures according to a normal operating configuration; further in the present description, the relative and absolute positions and orientations of the various elements that make up the unit, defined by terms such as upper and lower, above and below, horizontal and vertical or other equivalent terms, should always be interpreted with reference to said configuration.

[0072] The filtering unit 1 comprises a box-shaped housing 6, inside which the filtering operations of a liquid flow drawn from the aquarium tank and reintroduced thereinto after filtering are carried out.

[0073] Externally the housing 6 has the shape of a parallelepiped, whose lower portion has a receding side part to make room for a pump 5, preferably represented by a synchronous electric pump. In a per se known manner, the housing 6 is provided with a projecting portion for connection 22 that allows it to be hung on the back wall of the aquarium tank.

[0074] Starting from the side of the projecting portion for connection 22 corresponding to the side with receding part of the housing 6, an outer portion of a suction pipe 2 extends vertically downwards. The lower end of said suction pipe 2, arranged for immersing into the water of the aquarium tank, has a plurality of longitudinal slots 3a which define a water inlet 3 for the filtering unit 1.

[0075] Along the extension of the projecting portion for connection 22 not affected by the presence of the suction pipe 2, a drop spillway defining an outlet mouth 4 of the filtering unit 1 opens. Below said outlet mouth, on the projecting portion for connection 22 a return chute 23 is defined, intended to accompany the fall of water now filtered into the aquarium tank.

[0076] Between the inlet 3 and the outlet mouth 4 at least one recirculation path develops, and the aforementioned pump 5 is intended to favour the water circulation along said path. The recirculation path passes through one or more filters contained in the housing 6; a by-pass path, also exiting at the same outlet mouth 4, is generally provided to maintain the water recirculation even in case of filter obstruction.

[0077] For the purposes of the present invention, the path portion to be described is the one upstream of the pump 5, which is defined by a suction pipe 2. Said suction pipe 2 is U-shaped and is made of an ascending portion, which develops from the inlet 3 up to a top capable of climbing over the back wall of the aquarium tank, and of a descending portion 20, which reaches the pump volute.

[0078] Structurally, the suction pipe 2 is made of a U-segment 19 on which a straight segment 21 engages below, which defines the inlet 3 at the lower end thereof. The U-segment 19 and the straight segment 21 join together by means of a connection sleeve 17 which inserts externally to the first one and internally to the second one.

[0079] Above the connection sleeve 17, in the ascending segment 13, a non-return valve 10 is defined.

[0080] The non-return valve is made of a shutter body 12, which has the shape of a sphere of plastic material with a specific weight lower than the one of water, which in the rest configuration is housed in a seat 11, defined by the narrowing of the connection sleeve 17 where a toroidal sealing gasket 16 is housed.

[0081] When the pump 5 is in action, the water flow drags the sphere 12 upwards along the ascending segment 13, unlocking the seat 11 and freeing the passage toward the pump 5 itself.

[0082] At the top of the ascending segment 13, which develops along a longitudinal axis x, a side recess 14 is provided, in which the sphere 12 is guided by a top rib 18, made inside the U-segment 19 of the suction pipe 2. The recess 14, which has a lower support surface 15 sloped towards the ascending segment 13, is obtained below with respect to the bend of the U-segment 19, and thus is offset from a main water passage path.

[0083] When the pump 5 is in operation, the sphere 12 is kept in the recess 14 by the kinetic energy of the water flowing in the duct and does not hinder the flow thereof. When the action of the pump 5 stops, the sphere 12 dragged by the return water slides along the lower sloped surface 15; then, it falls along the ascending segment 13 repositioning itself in the seat 11 in the locked position. Thus the return of water towards the inlet opening 3 is prevented, and a volume is maintained in the descending portion 20 of the U-pipe to allow priming the pump 5 at the following start.

[0084] With reference to the enclosed FIGS. 5-7, reference number 1′ generically identifies a second embodiment of a filtering unit according to the present invention.

[0085] The filtering unit 1′ according to the second embodiment shares most of the components and features of the previous embodiment. Such components and features are therefore indicated in the figures by reference numerals previously used, and they are not described anew in the following paragraphs.

[0086] The filtering unit 1′ according to the second embodiment differs from the previous embodiment in that the suction pipe 2′ has an inlet body 24′ connected upstream, such an inlet body 24′ housing the non-return valve 10′.

[0087] The inlet body 24′ has an inlet body axis y which is slightly offset from the longitudinal axis x of the suction pipe, and it has a larger diameter so that the dimensions of the seat 11′ and shutter body 12′ are not constrained by the dimensions of the pipe 2′ above.

[0088] Preferably, the inlet body 24′ comprises a base element 25′ and a cover 26′. The bottom of the base element 25′ features a conical inlet 3′, having longitudinal slots for the access of water from the aquarium tank. Above, the base element 25′ features a cylindrical casing in which the cover 26′ is snap-fitted. The two elements may be disassembled for maintenance purpose. The cover 26′ has a dome-shaped top with a lateral aperture 29′ connecting with the lower end of the subsequent straight portion of the suction pipe 2′.

[0089] At the bottom of the cylindrical casing, above the conical inlet 3′, a disk-shaped insert 27′ is arranged that defines the seat 11′ of the non-return valve 10′. The disk-shaped insert 27′, which is preferably made of rubber, more preferably silicon rubber, features an inner hole contoured by a shaped lip 28′ onto which the shutter body 12′ accommodates.

[0090] In the actual embodiment, the shutter body 12′ is made as a sphere, just like in the first embodiment.

[0091] Within the inlet body 24′, an inner cavity 30′ is provided within which the water flows and the shutter body 12′ moves. The cover 26′ has inner radial ribs 31′ which guide the motion of the shutter body 12′ within the inner cavity along the inlet axis y′. In the depicted embodiment, the radial ribs 31′ are three in number, equally spaced along the cylindrical inner body of the cover 26′.

[0092] With reference to the enclosed FIGS. 10-12, reference number 1″ generically identifies a third embodiment of a filtering unit according to the present invention.

[0093] The third embodiment corresponds to the second embodiment apart from that a pre-filter 100 is provided around the conical inlet 3′.

[0094] The pre-filter 100 is a cylindrical foam filter with a density of 10 PPI (pores per inch) and a total diameter of 5 cm; however, as discussed in the summary of invention, these are indicative values which can be modified according to design needs.

[0095] The pre-filter 100 is made of a solid cylinder of foam provided with longitudinal cuts 101. Preferably, the longitudinal cuts 101 are two orthogonal cuts crossing on the axis of the pre-filter. The pre-filter 100 is mounted by wedging the conical inlet 3′ within the longitudinal cuts 101.

[0096] The pre-filter 100 has the sole purpose of preventing the access of larger debris that could possibly interfere with the operation of the non-return valve 10′.

[0097] FIGS. 15 and 16 relate to a fourth embodiment of a filtering unit according to the present invention.

[0098] The fourth embodiment substantially corresponds to the previously discussed second embodiment, except for the fact that the shutter body 12″′ is a cup-shaped body instead of a sphere. In particular, the shutter body 12″′ has a hemispherical bottom portion and an upper cylindrical wall, which is vertically guided by the radial ribs 31′.

[0099] FIGS. 17 and 18 relate to a fifth embodiment of a filtering unit according to the present invention.

[0100] The fifth embodiment substantially corresponds to the previously discussed fourth embodiment but features a pre-filter 100 according to the third embodiment.

[0101] FIGS. 19 and 20 relate to a sixth embodiment of a filtering unit according to the present invention.

[0102] The sixth embodiment substantially corresponds to the previously discussed fourth embodiment, except for the fact that the shutter body 12″″ is mushroom-shaped. In particular, the shutter body 12″″ has a hemispherical bottom portion and an inner shaft 32″″ which is slidingly engaged over a vertical guide pin 33″″ integral with the ceiling of the cover 26′.

[0103] FIGS. 21 and 22 relate to a seventh embodiment of a filtering unit according to the present invention.

[0104] The seventh embodiment substantially corresponds to the previously discussed sixth embodiment but features a pre-filter 100 according to the third embodiment.

[0105] The above-described invention solves the technical problem previously identified. Moreover, it has the advantage of avoiding the return of non-filtered water into the tank in the event of a power failure.

[0106] Obviously, a skilled person can make several changes and variants to the above-described filtering unit, in order to meet contingent and specific needs, all of them by the way contained in the scope of protection of the invention as defined by the following claims.