WO2020021393A1

WO2020021393A1 - Filtration device for drinking water

Info

Publication number: WO2020021393A1
Application number: PCT/IB2019/056104
Authority: WO
Inventors: Fabrizio APRILE
Original assignee: Pea & Promoplast S.R.L.
Priority date: 2018-07-27
Filing date: 2019-07-17
Publication date: 2020-01-30
Also published as: IT201800007571A1

Abstract

Drinking water filter wherein the filtration assembly (1) comprises at least one first and one second filtration stage arranged in series. One of said first and second filtration stage comprises an activated carbon pod (10) and the other of said first and second filtration stage comprises a tubular coil (11) containing therein particles of ceramic materials.

Description

" Fil tration device for drinking water"

★★★★

Field of the invention

The present invention regards a drinking water filter, and more in particular a water filtering device applicable to a tap supplied by a water supply system typically domestic, or to a portable container such as jug, a water bottle or a thermos, or even a shower or a household appliance supply pipe.

State of the prior art

The filtration of water by means of so-called "cartridge" devices is a purification technology based on the forced flow of water through one or more porous means made of different materials.

Patent EP-1656326 discloses a filtering device thus made comprising an activated carbon filter contained in a casing connected to a source of drinking water, for example a conventional tap for domestic use.

The main characteristic of the activated carbon filters lies in the capacity of retaining some substances, especially organic pollutant substances such as pesticides, solvents and by-products of the disinfection carried out using chlorine. However, such filters are not able to eliminate bacteria and nitrates or act on water hardness.

The patent application n° WO-200987670 regards a ceramic water filter operating by gravity. The ceramic filter is installed in a housing in turn arranged in a container filled with water to be filtered.

Such ceramic filters, at times referred to as candle filters, are suitable for filtering ultra-fine particles such as impurities suspended in water, bacteria and other microorganisms which are trapped on the surfaces of the ceramic elements.

Typically, such filters consist of ceramic or polypropylene particles housed in pressurised containers and they are used for reducing the microbial content and turbidities in small-size systems. The filtration process is thus capable of separating 0.2 pm to 1 pm particles from water adapting to the characteristics required for an optimal filtration of drinking water.

Considering the two different filtering properties of the aforementioned main types of filters available in the market, there arises the need for a filtering device capable of meeting both effectively having, at the same time, small dimensions that allow an easy and comfortable use thereof, for example, in a typical kitchen sink.

The international patent application n° W003041847A1 regards a drinking water filter for a tap comprising two filtration stages arranged in series radially outside a conduit for the inlet of the water to be filtered provided with holes over the entire length thereof.

Patent application n° US5269922A describes a drinking water filter wherein the water, after flowing through a coil containing a first filtering material, is introduced into the casing of the filter which contains a second filtering material which surrounds such coil. In both cases, the shape and the arrangement of the filtration stages in the filter do not allow a comfortable and easy access to each stage independently for a prompt and quick maintenance or replacement whenever required.

Summary of the invention

The object of the invention is to overcome the aforementioned problem in an efficient manner. According to the invention, this object is attained by means of the filtering device defined in claim 1.

In a first embodiment of the invention, the first filtration stage comprises a conduit having a first portion and a second portion connected by means of an inlet to said first portion and extending up to an end housing of said casing containing a filter in form of a pod comprising activated carbons for filtering the water coming from said inlet. The second filtration stage comprises the tubular coil containing said particles of ceramic materials for filtering the water coming from the first filtration stage, said tubular coil coaxially surrounding the second portion of the conduit .

According to this embodiment, the water coming from the source (supply system or container), before being available for a user, is subjected to a first filtration of the pollutant materials using activated carbons and a second filtration for reducing microbes and turbidity due to the ceramic materials or the like contained in the coil. In an embodiment of the invention, the coil can be made using a thermopolymer- copolymer for example of the type traded under the name ROSTRATE^®.

In another embodiment, the first filtration stage comprises the tubular coil containing the particles of ceramic materials for filtering the water coming from an inlet, and then second filtration stage comprises a container housed in which is the filter in form of a pod comprising activated carbons for filtering the water coming from said tubular coil which coaxially surrounds said container. In both embodiments, the flow of water in the first filtration stage is in the direction opposite to the one in the second filtration stage.

In other embodiments, more than two filtration stages in any case detachably connected to each other may be provided so as to facilitate maintenance thereof also allowing the replacement of each stage independently with respect to each other.

Further characteristics of the invention will be apparent from the detailed description that follows.

Brief description of the drawings

The invention will now be described in detail with reference to the attached drawings, provided purely by way of non-limiting example, wherein:

- figure 1 is a schematic perspective view of a first embodiment of the filtration device for drinking water according to the invention connected to an outlet of a typical domestic tap,

figure 2 is a transversal section and larger detail view of a part of figure 2,

- figure 3 is a sectional partial exploded view of an embodiment of the filtering device according to the invention,

- figure 4 is a view that shows a variant of the coil comprised in the second filtration stage, and

figure 5 schematically illustrates a second embodiment of the filtration device for drinking water according to the invention.

Detailed description of the invention

Initially with reference to figure 1, the filter according to the invention comprises a filtration assembly generally indicated with 1 which, in the case of the illustrated example, is connected by means of a portion 2a of a conduit 2 to an outlet 3 of a conventional tap R connected to a water supply system and provided with a water flow adjustment device F.

The portion 2a of the conduit 2 comprises a flow diverter 4 by means of which a user can choose to make the water flow through the filtration assembly 1 or directly to an unfiltered water outlet 5 provided for, in the case of the illustrated example, at an end of the portion 2a of the conduit 2.

The filtration assembly 1 is positioned at the other end of the portion 2a of the conduit 2 and it comprises a cylindrical casing 6 provided with an upper housing 7, a lid 8 and a filtered water outlet 9.

Provided for in the cylindrical casing 6, substantially coaxially thereto, is a portion 2b of the conduit 2 connected by means of an inlet 13 to the portion 2a of the conduit 2 and extending, vertically in this case, up to the upper housing 7.

As better observable in figure 2, the upper housing 7 is configured for housing - in the lower part thereof - an activated carbon filter 14, typically in form of a pod 10. The housing 7 further comprises an upper portion for containing the water coming from the portion 2b of the conduit 2 before it is filtered by the activated carbons 14.

The portion 2b of the conduit 2, the housing 7 and the activated carbon 14 filter 10 constitute the first water filtration stage.

Further provided for in the casing 6 is a tubular coil 11 which coaxially surrounds the portion 2b of the conduit 2. The upper end of the coil 11 is in fluid communication with the water filtered in the first filtration stage and the lower end thereof is connected to the filtered water outlet 9.

Such coil 11 may be obtained using a thermopolymer-copolymer, for example the one traded under the name ROSTRATE®, and it contains - therein - a second filtering material, for example micro-beads made of ceramic material 12, thus obtaining the second water filtration stage.

Figure 3 shows an explode view of an embodiment of the filtering device according to the invention wherein the housing 7 for the pod filter 10 is provided for in the lid 8 in turn screwed on the upper portion of the casing 6 thus sealing the filtration assembly 1.

Represented in figure 4 is a coil 11 having a different number of turns with respect to that of the coil 11 shown in figure 3.

Following is a description of how the filtering device according to the invention operates with reference to the arrows of figure 1.

By acting on the adjustment device F of the tap R, a user initially allows the water from the water supply system to flow into the first portion 2a of the conduit 2. Using the flow diverter 4, the water can be subsequently diverted directly to the outlet 5 or it can be introduced into the portion 2b of the conduit 2 so as to be filtered by the filtration assembly 1. The dispensing pressure typical of the water supply system allows the water to flow in source the portion 2b of the conduit 2, to fill the upper portion of the housing 7, to flow through the activated carbons 14 of the pod filter 10 of the first filtration stage, to flow in the coil 11 containing the micro-beads made of ceramic material 12 of the second filtration stage and lastly flow out from the filtered water outlet 9.

Obviously, the construction details and the embodiments may widely vary with respect to what has been described and illustrated, without departing from the scope of protection of the present invention as defined in the claims that follow.

Thus, the general shape and orientation of the filtering device could be different from those represented in the drawings, and for example the axis of the portion 2b of the conduit 2 and of the coil 11 could be arranged horizontally instead of vertically.

In a variant of the invention, not illustrated, the filter according to the invention may comprise one or more further filtration stages.

In another embodiment not illustrated, the portion 2a of the conduit 2 comprises a propeller, driven by the water flow, and an electronic circuit, powered by a battery, arranged to compute and display the filtered water quantity. The electronic circuit, known to a man skilled in the art, may comprise a led for interfacing with the user for signalling, for example, the state of wear or clogging of the filters.

In the variant of the invention schematically illustrated in figure 5 the arrangement of the first and of the second filtration stage is inverted with respect to the first embodiment described previously. In this variant, the tubular coil 11 containing said particles of ceramic materials 12 is connected - at the lower part - with the inlet 13 of the water to be filtered and supplies - from above surrounding it coaxially - a container 15 housed in which is the filter in form of pod 10 comprising activated carbons 14 for filtering the water coming from the tubular coil 11. The container 15 communicates - at the lower part - with the filtered water outlet 9.

In both embodiments described above, the flow of the water in the first filtration stage is in the opposite direction with respect to the one in the second filtration stage, and the two filtration stages are easily accessible by removing the lid 8 and thus detachable . Lastly, it should be observed that, though in the described example the filter is applied to a water supply system tap, the invention may also be advantageously applied to a shower or a household appliance supply pipe as well as to a portable container such as a jug, a water bottle, a thermos and the like. Furthermore, the ceramic micro-beads could be replaced by or mixed with resins.

Claims

1. Filtration device for drinking water comprising :

a casing (6) having:

- a water inlet (13),

- a filtration assembly (1),

- a filtered water outlet (9),

said filtration assembly (1) comprising at least a first filtration stage and a second filtration stage arranged in series, characterised in that one of said first and second filtration stage comprises an activated carbon pod (10, 14) and the other of said first and second filtration stage comprises a tubular coil (11) containing - therein - particles of ceramic and/or resin materials (12) .

2 . Device according to claim 1, characterised in that the first filtration stage comprises a conduit (2) having a first portion (2a) and a second portion (2b) connected by means of an inlet (13) to said first portion (2a) and extending up to an end housing (7) of said casing (6) containing said filter in form of a pod comprising activated carbons (10, 14) for filtering the water coming from said inlet (13), and the second filtration stage comprises said tubular coil (11) containing said particles of ceramic materials (12) for filtering the water coming from the first filtration stage, said tubular coil (11) coaxially surrounding said second portion (2b) of the conduit (2) .

3 . Device according to claim 1, characterised in that the first filtration stage comprises the tubular coil (11) containing said particles of ceramic materials (12) for filtering the water coming from an inlet (2), and said second filtration stage comprises a container (15) housed in which is said filter in form of a pod comprising activated carbons (10, 14) for filtering the water coming from said tubular coil (11); said tubular coil (11) coaxially surrounding said container ( 15) .

4 . Device according to claim 2 or 3, characterised in that the flow of water in the first filtration stage is in the direction opposite to the one in the second filtration stage.

5 . Device according to one or more of the preceding claims, characterised in that said container is provided with a lid (8) that can be opened for access to said first and second filtration stage.

6. Device according to any one of the preceding claims, characterised in that said coil (11) is obtained using a thermopolymer-copolymer.

7 . Device according to any one of the preceding claims, characterised in that it comprises one or more further filtration stages.

8. Device according to any one of the preceding claims, characterised in that said first and second filtration stage are detachably connected to each other .

9 . Device according to claim 2, characterised in that a portion of said housing (7) is configured to contain water before it is filtered by said pod filter (10) .

10 . Device according to one or more of the preceding claims, characterised in that it is provided with means for computing and displaying the amount of filtered water and means for signalling the state of wear of the filters (12, 14) .

11 . Device according to one or more of the preceding claims, characterised in that it is suitable to be applied to a water supply system tap, to the shower or a household appliance supply pipe, to a portable container such as a jug, a water bottle, a thermos , and the like.