WO2017064692A1

WO2017064692A1 - Self-cleaning scanner filter

Info

Publication number: WO2017064692A1
Application number: PCT/IL2015/051245
Authority: WO
Inventors: Rotem BARAK
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-10-12
Filing date: 2015-12-23
Publication date: 2017-04-20
Anticipated expiration: 2018-04-12

Abstract

A self-cleaning scanner filter includes a filter mesh, a scanner and a suction head. The self- cleaning scanner filter is configured to be compact and clean efficiently. The filter mesh includes at least a first pair of opposing top and bottom surfaces, at least one of the top and bottom surfaces is formed with an opening sized to accommodate the scanner therethrough.

Description

SELF-CLEANING SCANNER FILTER

FIELD OF THE INVENTION

The present disclosure generally relates to the field of liquid filtration and more particularly to a filter comprising a scanner for self-cleaning.

BACKGROUND OF THE INVENTION

Filters with self-cleaning capability can operate as follows. Unfiltered fluid enters through an inlet of a filter body, and a metal or plastic filter mesh separates the liquid and solid parts of the fluid. The filtered fluid exits an outlet of the filter body. When the filter mesh is clogged by solid parts, a differential pressure is created between the sides of the filter mesh. At this point a suction system (scanner) is activated, which draws the solid parts accumulated on the filter mesh through another outlet. Suction can be created as a result of the pressure drop between the atmospheric pressure to the pressure inside the filter body. The suction system can be activated until equal (or close to equal) pressure between the sides of the filter mesh is achieved.

An example use for a self-cleaning filter is filtration of ballast water on sea vessels. Due to limited space on a sea vessel compactness is a preference. Similarly, due to power restrictions filters which operate with only low pressure (e.g. approximately 2 bar or less) are often preferred.

Accordingly a compact filter capable of being operated with low pressure is desirable, inter alia, for use on sea vessels.

It is an object of the subject matter of the present application to provide an improved self- cleaning scanner filter and/or components thereof.

SUMMARY OF THE INVENTION

According to one aspect of the subject matter of the present application, there is provided a filter mesh comprising at least a first pair of opposing top and bottom surfaces connected along a circumferentially extending peripheral edge, at least one of the top and bottom surfaces is formed with an opening; and a central axis extends through the center of the top and bottom surfaces; wherein: a maximum radial dimension, perpendicular to the central axis, of the first pair of top and bottom surfaces is greater than a maximum axial dimension, along the central axis, of the first pair of top and bottom surfaces; and/or the filter mesh further comprises a second pair of opposing top and bottom surfaces connected along a circumferentially extending peripheral edge, at least one of the top and bottom surfaces of the second pair is formed with an opening, and the opening of the first pair and the opening of the second pair are adjacent and in fluid communication with each other.

According to yet another aspect of the present application, there is provided a scanner comprising at least two conduits, each of the at least two conduits comprising a first opening and a second opening; and each of the second openings being in fluid communication with a different suction head. According to another aspect of the present application, there is provided a method of cleaning a filter mesh with a scanner comprising at least two conduits, each of the at least two conduits having at least one suction head, the method comprising: creating a differential pressure to at least one of the conduits while not creating a differential pressure to the another one of the conduits; and then halting the differential pressure to the at least one conduit and creating a differential pressure to another one of the conduits.

According to still another aspect of the present application, there is provided a suction head comprising a manifold connector and at least two finger sub-heads; each finger sub-head comprising an outlet aperture being in fluid communication with an opening of the manifold connector and an inlet aperture spaced apart from the manifold connector. According to another aspect of the present application, there is provided a self-cleaning filter comprising in combination a filter mesh, a scanner and at least one suction head. One or more of the filter mesh, scanner and at least one suction head are in accordance with one of the above aspects.

It will be understood that the above-said is a summary, and that any of the aspects above may further comprise any of the features described hereinbelow. Specifically, the following features, either alone or in combination, may be applicable to any of the above aspects:

A. A filter mesh can comprise at least a first pair of opposing top and bottom surfaces.

B. A pair of top and bottom surfaces can be formed with an opening. Each of the pair of top and bottom surfaces can be formed with an opening (i.e. the pair can comprise both top and bottom openings). The openings can be coaxial. The opening or openings of the pair can be coaxial with the openings of one or more additional pairs of top and bottom surfaces of the filter mesh. Each opening can be sized and positioned to receive a portion of a scanner therethrough. c. A pair of top and bottom surfaces can comprise a circumferentially extending peripheral edge along which the top and bottom surfaces are connected.

D. A central axis can extend through a center of the top and bottom surfaces.

E. A maximum radial dimension of a pair of top and bottom surfaces which is perpendicular to a central axis can be greater than a maximum axial dimension along the central axis.

F. A filter mesh can comprise at least a second pair of opposing top and bottom surfaces. Adjacent openings of different pairs of top and bottom surfaces can be in fluid communication with each other. Adjacent openings can be joined to each other along the edges of each respective opening.

G. At least portions of opposing surfaces of adjacent pairs of top and bottom surfaces can be partially spaced from each other. For example, a top surface of a first pair which is adjacent to a bottom surface of a second pair can be connected at adjacent openings of each pair and spaced apart from the openings in the radial direction there can be a gap between the top surface of the first pair and bottom surface of the second pair.

H. A second pair, or a plurality of additional pairs, of top and bottom surfaces can be formed with an opening, and a circumferentially extending peripheral edge along which the top and bottom surfaces of the second pair are connected. A filter mesh can comprise a plurality of such pairs of top and bottom surfaces.

I. A second pair, or a plurality of additional pairs, of top and bottom surfaces can comprise an opening coaxial with an opening of a first pair of top and bottom surfaces.

J. A second pair of top and bottom surfaces can be in fluid communication with a first pair of top and bottom surfaces. . A second pair of top and bottom surfaces can have an identical construction to a first pair. Each pair of top and bottom surfaces can have identical constructions to all other pairs of the filter mesh.

L. A filter mesh can comprise three or more pairs of opposing top and bottom surfaces serially connected to each other.

M. Each pair of top and bottom surfaces of a filter mesh can be aligned axially. N. A filter mesh can formed as a single unitary component. Alternatively, each top and bottom surface can be a separate piece either being removably connected to each other or permanently bonded to each other. Alternatively, each pair of top and bottom surfaces can be permanently bonded to each other but removably connected to one or more adjacent pairs. Still alternatively, adjacent surfaces of two different pairs can be permanently bonded to each other but removably connected to the other surface of the common pair.

O. An entirety of a filter mesh can be mesh (i.e. liquid can pass through all portions thereof, even the peripheral edge). Alternatively, top and bottom surfaces of a filter mesh can comprise mesh and can be connected by a peripheral edge which is non-porous. In the latter case the non- porous peripheral edge can be equal to at least a third of the axial height of the pair. In some embodiments (e.g. see fig. 4C) the peripheral edge can be equal to the entire height of the associated pair. P. Each pair of top and bottom surfaces of a filter mesh can be partial conic units connected to each other head to tail. Alternatively, top and bottom surfaces of a filter mesh can extend parallel to each other.

Each pair of top and bottom surfaces can taper to a peripheral edge at an internal tapering angle a of 25° ± 10°. Without being bound to theory, it is believed that angles tending to 25° are preferred.

Q. An opening formed in a top or bottom surface can comprises a circumferentially protruding lip.

A sealing element can be mounted on the lip.

R. A filter mesh can be made of metal or plastic.

S. A scanner can comprise at least two conduits. A scanner can comprise at least three conduits. T. Each conduit of a scanner can be adjacent to each other.

U. Each conduit of a scanner can extend in an axial direction and suction heads can extend transverse to the axial direction.

V. Suction heads of a scanner can normally (i.e. without being biased by contact with a filter mesh being cleaned) extend in a radial direction. Note this radial direction can be transverse somewhat to the radial direction, i.e. extending in a generally radial direction.

W. A conduit can comprise a first and second end. The conduit can have a tubular shape extending from the first end to the second end. An opening or openings of the conduit can be located at locations spaced apart from the first and second ends. In other words the opening or openings can be formed in the tubular portion of the conduit. X. A first end of a conduit can comprise a first opening.

Y. Conduits of a scanner can be closed at a second end which is distal from a first end thereof.

Stated differently, a second end of a conduit can be closed.

Z. At least one conduit of the scanner can comprise an opening in fluid connection with another suction head. Stated differently, the conduit can comprise more than one opening, in addition to an opening at a first end thereof, and a suction head in fluid connection with each opening except for the opening at the first end.

AA. First ends of each conduit of a scanner can be connected to a common conduit housing.

BB. Suction heads of different conduits can be spaced axially from each other. CC. Suction heads of different conduits can be spaced circumferentially from each other.

DD. Each conduit can comprise a first opening and a second opening.

EE. Each second opening of a conduit can be in fluid communication with a different suction head.

FF. A method of cleaning can comprise creating a differential pressure to a first conduit while not creating a differential pressure to a second conduit; and halting the differential pressure to the first conduit and creating a differential pressure to a second conduit.

GG. A suction head can comprise a manifold connector and at least two finger sub-heads.

HH. A finger sub-head can comprise an outlet aperture being in fluid communication with an opening of a manifold connector and an inlet aperture spaced apart from a manifold connector.

II. Each finger sub-head can be pivotably and/or flexibly connected to the manifold connector. JJ. Each finger sub-head can be configured to revert to an initial position. For example the finger sub-head or a portion thereof can be elastic (either elastic in property or comprising a spring etc.). . An inlet aperture of a finger sub-head can be elongated.

LL. Inlet apertures of each finger sub-head can be facing different directions. Inlet apertures can face opposite directions. MM. Finger sub-heads can be offset radially and/or axially to allow unimpeded movement with the adjacent finger-sub-head.

NN. Finger sub-heads can have a tapering shape.

00. Finger sub-heads can be elongated. PP. Each inlet aperture can be surrounded by a sealing member. Such sealing member is for improving sealing connection with a filter mesh.

QQ. A self-cleaning filter can comprise a filter mesh comprising a single pair of top and bottom surfaces. Alternatively, a self-cleaning filter can comprise a filter mesh comprising a plurality of pairs of top and bottom surfaces. RR. A self-cleaning filter can comprise a non-porous filter housing formed with an inlet and an outlet. A filter mesh can be located inside the housing. A scanner can be located partially inside and partially protruding from the housing.

SS. A self-cleaning filter can be formed with at least one flange.

TT.An opening angle of finger sub-heads of a scanner can be greater than an associated tapering angle of one of a pair of top and bottom surfaces (i.e. a/2).

UU. A self-cleaning filter can comprise or be configured for connection to an electric valve unit configured for selectively applying differential pressure to at least one of the at least two conduits. The electric valve unit can be configured also to apply differential pressure to all of the at least two conduits.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A is a perspective view of a self-cleaning filter. FIG. IB is a side view of the self-cleaning filter in Fig. 1 A. FIG. 1C is a section view along line 1C-1C in Fig. IB. FIG. 2 is perspective view of a filter mesh shown in Fig. 1C.

FIG. 3 A is a perspective view of a scanner shown in Figs. 1 A to 1C. FIG. 3B is a perspective view of a suction head shown in Fig. 3A.

FIG. 4A is a perspective view of another filter mesh.

FIG. 4B is an end (axial) view of a filter mesh shown in Fig. 4 A.

FIG. 4C is a side view of a filter mesh shown in Figs. 4A and 4B.

DETAILED DESCRIPTION

Referring to Figs. 1A to 1C there is illustrated a self-cleaning filter generally designated 10. The filter 10 comprises an inlet 12 and an outlet 14 formed in a non-porous filter housing

16.

A central axis (A) extends through the center of the filter 10 (Fig. 1C).

The filter can comprise flanges 18A, 18B, 18C having apertures 20 for secure attachment to other components (not shown).

The filter 10 can comprise a filter mesh 22 and a scanner 24.

In this example the filter mesh 22 comprises a plurality of pairs 24 of bottom and top surfaces 26, 28 (26A, 26B, 26C, 26D, 26E, 26F, 28A, 28B, 28C, 28D, 28E, 28F). More specifically, there is shown first, second, third, fourth, fifth and sixth pairs 24A, 24B, 24C, 24D, 24E, 24F, with associated surfaces having the same identifying character.

As best shown in Figs. 1C and 2, each pair 24 is formed with upper and lower openings 30, 32. To elaborate, the first pair 24A comprises a first top opening 30A formed in the first top surface 28A and a first bottom opening 32A formed in the first bottom surface 26A.

Similarly, the second pair 24B comprises a top opening 30B formed in the second top surface 28B and a first bottom opening 32B formed in the first bottom surface 26B.

An annular lip 34A extends axially upward from the first top opening 3 OA to the filter housing 16 and an annular sealing element 36A is mounted thereon.

As shown, a symmetric arrangement can exist at the other end of the filter mesh 22 with a lowermost opening having an annular lip 34B extending axially downward therefrom to the filter housing 16 and an annular sealing element 36B is mounted thereon. Each pair 24 of surfaces is joined to an opening of an adjacent pair 24. For example, the first and second pairs 24A, 24B are joined and in fluid communication via the first bottom opening 32A and the top opening 3 OB.

Each pair 24 of top and bottom surfaces 28, 26 meet at a circumferentially extending peripheral edge 38 (38 A, 38B, 38C, 38D, 38E, 38F).

In this example the bottom and top surfaces 26, 28, at least excluding the openings 30, 32, can be mesh until the edge where they meet.

In this example, the bottom and top surfaces 26, 28 are optionally welded together, as are the adjacent pairs 24 along the openings 30, 32 excluding the uppermost and lowermost openings 30, 32 which have lips 34 extending therefrom.

Preferably, a maximum radial dimension Dl measured in a radial direction DR which is perpendicular to the central axis A, is greater than a maximum axial dimension D2 measured in an axial direction DA measured along the central axis. As shown the radial dimension Dl can preferably be at least three or four times the magnitude of the axial dimension D2.

Each pair 24 of bottom and top surfaces 26, 28 can taper as shown and form an internal tapering angle a at, for example, 25°. As can be understood, each of the top and bottom surfaces 26, 28 can separately taper at an angle of 12.5° (a/2; in a case where the taper is symmetric for both surfaces) with the radial direction DR.

Notably, at least portions 40A, 40B of opposing surfaces 26A, 28B can be partially spaced from each other, e.g. see a gap designated as 42.

The scanner 24 can comprise conduits 44. In this example there are first, second and third conduits 44A, 44B, 44C.

Using the first conduit 44A, as shown in Fig. 1C as an example to the identical conduits, it is shown there is a first opening 46A and a second opening 48A. Notably, the openings 46A and 48A do not have to be at opposing first and second ends 45, 47 of the conduit 44 A. Notably one end, in this example the second end of the first conduit designated 50A of the first conduit 44A is a blind end (i.e. closed). The first conduit 44A can comprise additional openings, e.g., a third opening 52A which similar to the second opening 48A which opens transverse to the axis A.

Each of the second and third openings 48A, 52A are in fluid communication with a respective different suction head 54A1, 54A2. Each first end 45 is received in, and in fluid communication with, a conduit housing 56 the scanner 24.

The conduit housing 56 has an opening 58A, 58B, 58C for each conduit 44A, 44B, 44C.

In operation, for example, an electric valve unit (not shown) can be configured to selectively open and close different openings 58 A, 58B, 58C in order to allow differential pressure to be applied to a selected conduit, e.g. applying differential pressure to only the first conduit 44A via the associated first opening 58 A. Subsequently, for example, the electric valve unit can then close the first opening 58A (or a pipe in fluid communication therewith) and can open a different opening.

This allows dirt or debris which is clogging the inside of the filter mesh 22 to be removed via suction of the suction heads 54 and exit the open opening 58, thereby cleaning the filter mesh 22.

More specifically, differential pressure, when applied, for example, to the first conduit 44A, causes the suction heads 54A1, 54A2 to draw out dirt from the associated pair 24, which in this case are the third and sixth pairs 24C, 24F. Notably, each conduit 44 can be adjacent to each other and be centrally located in the filter

10, or more precisely the filter mesh 22, to allow the scanner 24 to be rotated. Such rotation can allow the radially extending suction heads 54 to clean the pair 24 of surfaces within which they are located. It will be understood that one suction head 54 per pair 24 may be sufficient, especially for low pressure applications, and so each suction head 54 can be axially spaced from the others. Referring to Fig. 3B, an advantageous suction head type 54 will now be described in further detail. To explain the relationship with the other components, it is exemplified as the suction head designated 54A1.

The suction head 54A1 can comprise a manifold connector 60A and at least two finger subheads 62 A, 62B. Each finger sub-head 62A, 62B comprises an outlet aperture 64A (shown in Fig. 1C) being in fluid communication with an opening of the manifold connector 60A, and an inlet aperture 66A spaced apart from the manifold connector 60A. It will be understood that when differential pressure is applied to the suction head 54A1, dirt is drawn through to inlet aperture 66A and through the outlet aperture 64A to the manifold connector 60A and from there into the associated conduit 44A. As shown in Fig. 1C, each finger sub-head corresponds to the shape of the tapered surface of an associated pair 24 (e.g. top surface 28F which is adjacent to the finger sub-head designated 62A).

Advantageously the inlet aperture 66A can be elongated to contact a large length of the associated surface 28F. Each inlet aperture 66A can be surrounded with a sealing member 67A.

While the finger sub-heads 62 can have basically the same shape as the associated surface (26 or 28), an opening angle β (e.g. see the finger sub-head 62A in Fig. 1 C) of finger sub-heads 62 can be equal to or even greater than the tapering angle of one the pair of top and bottom surfaces (26, 28) which in this case is a/2 (since the surfaces have identical shapes, only inverted relative to each other). Such angle, may increase contact between the finger sub-head 62 with the associated mesh surface (26 or 28).

Yet another measure to increase contact is configuration of each finger sub-head 62 to be pivotably and/or flexibly connected to the manifold connector 60.

Each finger sub-head 62 can be configured to normally be in the position shown in Figs. 1C and 3A and to revert to this position, e.g. the connection to the manifold can be elastic. Thus when the mesh is irregularly shaped or there is contact with dirt etc. a smooth rotational movement will not be impeded due to the freedom of motion of the finger sub-head 62.

This advantage of smooth motion is further allowed by dividing the suction head 54 to more than one finger sub-head 62. By directing the inlet apertures of each finger sub-head in a different direction they each clean a different surface 26, 28.

While the finger sub-heads 62 could be configured for movement in any specific direction, it is advantageous that they be positioned so as not to abut each other. Upon close review of the drawings, it can be seen that the finger sub-heads 62 are offset radially and axially.

Referring now to Figs. 4A to 4C, an alternative filter mesh 68 is shown.

Except for the differences mentioned below the alternative filter mesh 68 is generally similar to the filter mesh 22 described above.

In this example the filter mesh 68 comprises a plurality of pairs of top and bottom surfaces. More specifically, there is shown first, second, third and fourth pairs 70A, 70B, 70C, 70D. Since each pair 70 is identical only the first pair 70A will be described.

The first pair 70A comprises top and bottom surfaces 72, 74. The top and bottom surfaces 72, 74 meet at a circumferentially extending peripheral edge

76A.

Whereas the previously described filter mesh 22 was mesh until the peripheral edge 38 thereof, in this example the first peripheral edge 76A is not porous (i.e. not mesh).

In this example, the top and bottom surfaces 72, 74 extend parallel to each other.

Accordingly, a suction head (not shown) or more precisely fingers thereof (in an embodiment where separate fingers are used) may also not be tapered. They may be cuboids or rectangular cuboids or may even have the same geometry (i.e. tapered) as shown but extend with their inlets parallel to each other.

It will be understood that the embodiments exemplified above are not intended to preclude non-exemplified embodiments from the scope of the claims.

Claims

1. A filter mesh:

comprising at least a first pair of opposing top and bottom surfaces connected along a circumferentially extending peripheral edge,

at least one of the top and bottom surfaces is formed with an opening; and

a central axis extends through the center of the top and bottom surfaces;

wherein:

a maximum radial dimension, perpendicular to the central axis, of the first pair of top and bottom surfaces is greater than a maximum axial dimension, along the central axis, of the first pair of top and bottom surfaces;

and/or

the filter mesh further comprises a second pair of opposing top and bottom surfaces connected along a circumferentially extending peripheral edge, at least one of the top and bottom surfaces of the second pair is formed with an opening, and the opening of the first pair and the opening of the second pair are adjacent and in fluid communication with each other.

2. The filter mesh according to claim 1, wherein there are three or more pairs of opposing top and bottom surfaces serially connected to each other.

3. The filter mesh according to claim 1 or 2, wherein each connected pair of opposing top and bottom surfaces is aligned axially.

4. The filter mesh according to any one of claims 1 to 3, wherein each pair of top and bottom surfaces are partial conic units connected to each other head to tail.

5. The filter mesh according to any one of claims 1 to 4, wherein each pair of top and bottom surfaces taper to a peripheral edge at an internal tapering angle a of 25° ± 10°.

6. The filter mesh according to any one of claims 1 to 5, wherein said opening further comprises a circumferentially protruding lip and a sealing element is mounted on the lip.

7. A scanner comprising at least two conduits; each of the at least two conduits comprising a first opening and a second opening; and each of the second openings being in fluid communication with a different suction head.

8. The scanner according to claim 7, wherein the at least two conduits are adjacent to each other.

9. The scanner according to claim 7 or 8, wherein the at least two conduits extend in an axial direction and the suction heads extend transverse to the axial direction.

10. The scanner according to any one of claims 7 to 9, wherein the conduits are closed at a second end which is distal from the first end, the first end comprises the first opening.

1 1. The scanner according to any one of claims 7 to 10, wherein the first ends of each of the at least two conduits are connected to a common conduit housing.

12. The scanner according to any one of claims 7 to 1 1, wherein the suction heads of different conduits are spaced axially from each other.

13. A suction head comprising a manifold connector and at least two finger sub-heads; each finger sub-head comprising an outlet aperture being in fluid communication with an opening of the manifold connector and an inlet aperture spaced apart from the manifold connector.

14. The suction head according to claim 13, wherein each finger sub-head is pivotably and/or flexibly connected to the manifold connector and configured to revert to an initial position.

15. The suction head according to claim 13 or 14, wherein the inlet aperture is elongated.

16. The suction head according to any one of claims 13 to 15, wherein the finger sub-heads are offset radially and/or axially to allow unimpeded movement with the adjacent finger-sub-head.

17. The suction head according to any one of claims 13 to 16, wherein the finger sub-heads are elongated.

18. The suction head according to any one of claims 13 to 17, wherein each inlet aperture is surrounded by a sealing member to improve sealing connection with a filter mesh.

19. A self-cleaning filter comprising a non-porous filter housing formed with an inlet, an outlet and at least one flange, and comprising in combination:

a filter mesh according to any one of claims 1 to 6;

a scanner according to any one of claims 7 to 12;

at least one suction head according to any one of claims 13 to 18; and

wherein for each pair of top and bottom surfaces there is a single suction head.

20. The self-cleaning filter according to claim 19, wherein an opening angle of finger sub-heads of a scanner is greater than the tapering angle of an associated of one of the pair of top and bottom surfaces.