WO2013117988A1

WO2013117988A1 - A filter cartridge

Info

Publication number: WO2013117988A1
Application number: PCT/IB2013/000166
Authority: WO
Inventors: Giorgio Girondi
Original assignee: Ufi Filters S.P.A.
Priority date: 2012-02-08
Filing date: 2013-02-06
Publication date: 2013-08-15
Also published as: ITRE20120007A1; CN104487151A; CN104487151B

Abstract

A filter cartridge (20, 30), suitable for being contained internally of an external casing (10) provided with an inlet (11) and an outlet (12) such as to filter the fluid which flows from the inlet (1 1 ) towards the outlet (12), which filter cartridge (20, 30) comprises at least a filter wall (22, 32) and a support flange (213a, 314) fixed to the filter wall (22, 32) and destined to sub-divide the internal volume of the casing (10) into a first chamber (15) communicating with the inlet (1 1 ) and a second chamber (16) communicating with the outlet (12), in communication with one another via the filter wall (22, 32), characterised in that it comprises at least a collecting body (21, 31) associated to the support flange (213a, 314) and destined to define a collecting volume communicating with the first chamber (15) such as to collect the particulate separating from the fluid to be filtered.

Description

A FILTER CARTRIDGE

TECHNICAL FIELD

The present invention relates in general to the filtration of fluids, especially the filtration of motor fluids, among which in particular the filtering of air that is aspirated by an internal combustion engine.

PRIOR ART

As is known, the air (or in general any gas) which is aspirated by an internal combustion engine must commonly be subjected to a filtration step, with the aim of purifying the air from the solid particles in suspension therein, typically powders of various types or moisture levels, such that the particles cannot reach the combustion chambers of the engine. The filtration step is typically carried out by a suitable filter group, which is located along the aspirating conduit of the internal combustion engine, upstream of the aspiration manifold and the turbo-compressor if present.

The filter group schematically comprises an external casing, usually called the filter case, which is provided with an inlet for the air to be filtered and an outlet of the filtered air, and a filter cartridge housed in the filter casing for filtering the air which flows from the inlet towards the outlet.

On-board a vehicle, the filter casing is normally located internally of the engine compartment, where it is associated to a first conduit destined to connect the air inlet with an air intake afforded in the bonnet or in the frontal part of the vehicle, and to a second conduit destined to connect the air outlet to the aspiration manifold of the engine.

The filter cartridge comprises at least a filter wall, or an element made of filtering material, for example based on cellulose or a polymer material, and at least a support flange for the element made of a filtering material. The support flange is engaged to the filter casing in such a way that the element of filtering material is destined to sub-divide the internal volume into two distinct chambers, of which a first chamber communicating with the inlet and a second chamber communicating with the outlet. In this way, the air flowing from the inlet towards the outlet of the filter casing is forced to cross the filter material element, which retains the solid particles to be separated from the air in the first chamber, leaving the second chamber into which the purified air flows clean. Since the solid particles progressively obstruct the filter material element, it is common practice for the filter cartridge to be removed from the filter casing, so that it can be replaced when the filter material element is excessively blocked.

One of the main needs connected with this type of filter group consists in the fact of guaranteeing that the second chamber, i.e. the chamber located downstream of the filter wall, and also the conduits opening into it, must never get contaminated by the particulate that is removed from the filter wall, such that only filtered and clean air can be supplied to the internal combustion engine.

A drawback that is generally encountered in filter groups of known type is that although the filtration step exhibits a high degree of efficiency and in use the first chamber and the second chamber are in fact separate from the filter wall, the separation in reality does not exist, though for a limited time period, each time it becomes necessary to remove the filter wall in order to perform its periodical replacement.

It is found that the excess particulate which enters the first chamber of the casing deposits not only on the surface of the filter wall facing towards the first chamber but also on the internal walls of the first chamber itself.

The personnel performing the periodical replacement of the filter wall, therefore, is forced to perform the replacement operations taking great care such as to prevent the particulate, once the cartridge has been removed, does not fall internally of the second chamber and is therefore downstream of the new filter wall which is installed internally of the casing and flows into the aspirating manifold of the engine.

Examples of filter cartridges, in which a support flange is conformed as a tray and is suitable to collect the particulate, are shown in document D2 (U.S. 2006/065 592), although for making the same particularly complex and laborious operations are necessary to fix the filter wall to the support flange.

An aim of the present invention is to obviate the above-mentioned drawbacks of the prior art, with a solution that is simple, rational and relatively inexpensive.

The aims are attained by the characteristics of the invention as set out in the independent claim. The dependent claims delineate preferred and/or particularly advantageous aspects of the invention.

DISCLOSURE OF THE INVENTION

The invention in particular discloses a filter cartridge, suitable for being contained internally of an external casing provided with an inlet and an outlet such as to filter the fluid which flows from the inlet towards the outlet, which filter cartridge comprises at least a filter wall and a support flange fixed to the filter wall and destined to subdivide the internal volume of the casing into a first chamber communicating with the inlet and a second chamber communicating with the outlet, in communication with one another via the filter wall.

According to the invention, the filter cartridge comprises at least a collecting body associated to the support flange and suitable for defining a collecting volume communicating with the first chamber such as to collect the particulate, separating itself from the fluid to be filtered and retaining it internally thereof.

With this solution, the contaminant separated from the air to be filtered remains contained internally of the collecting body, preventing contamination of the zone of the casing located downstream of the filter wall.

In an aspect of the invention, the collecting body is realised in a single piece with the support flange.

In this way, the collecting body is easy to realise and safe to use, and the whole filter cartridge can be replaced, as can the collecting body, in a single operation.

In a still further aspect of the invention, the collecting body is substantially tray-shaped and is provided with an open wall suitable for setting the first chamber in communication with the internal volume of the collecting body, the support flange defining at least a wall of the collecting body.

Moreover, the support flange delimits a passage opening suitable for setting the internal volume of the collecting body in communication with the external volume of the same.

The filter wall is directly fixed to the entire peripheral edge of the passage opening, such as to completely occlude said passage opening.

With this solution, the collecting body defines a concave zone, formed by the walls of the collecting body itself and the filter wall, which is suitable for collecting on the walls thereof the contaminant to be separated from the air to be filtered, enabling effect collection thereof and preventing the walls of the casing from being dirtied.

Moreover, thanks to this solution, the fixing operations of the filter wall to the collecting body are particularly simple, economical, quick and effective, allowing a reduction of production costs of the filter cartridge.

Also, at least one of the support flange and the collecting body advantageously comprises at least a perimeter edge to which a seal is fixed that is destined to be associated to the casing for the sealed separating between the first chamber and the second chamber.

Thanks to this solution, the replacement of the cartridge is carried out contextually with the replacement of the seal, and in a single operation by the maintenance personnel, thus preventing the seal performance from deteriorating due to wear on the seal.

In a further aspect of the invention, the cartridge comprises separating tabs associated to the collecting body and destined to convey the fluid to be filtered towards the filter wall.

Thanks to the separating tabs, the air to be filtered is conveyed towards the filter wall, at the same time enabling a pre-separating of the coarser contaminant present in the air to be filtered, which strikes against the tabs and is deposited into the body of the collecting body, thus enabling the working life of the filter wall to be increased.

In a further aspect of the invention, a filter group is disclosed for an internal combustion engine, characterised in that it comprises an external casing provided with an inlet and an outlet and a filter cartridge, located internally of the casing in such a way as to filter the fluid that flows from the inlet towards the outlet. The casing of the group advantageously comprises a first body in which the first inlet is defined and a second body in which the outlet is defined, the seal being suitable for being interposed between the first body and the second body of the casing for the sealed separating between the first chamber and the second chamber.

BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics and advantages of the invention will emerge from a reading of the following description provided by way of non-limiting example, with the aid of the figures illustrated in the accompanying tables of drawings. Figure 1 is a front view of a filter group according to the invention.

Figure 2 is a lateral view of figure 1.

Figure 3 is section Ill-Ill of figure 1 , with an internal filter cartridge according to a first embodiment of the invention.

Figure 4 is section IV-IV of figure 2.

Figure 5 is a lateral view of a filter cartridge according to a first embodiment. Figure 6 is an axonometric view of figure 5.

Figure 7 is section VII-VII of figure 5.

Figure 8 is a frontal view of figure 5.

Figure 9 is a view along section plane IV-IV of figure 1 , with an internal filter cartridge according to a second embodiment of the invention.

Figure 10 is an axonometric view of a filter cartridge according to the second embodiment.

Figure 1 1 is a view from XI of figure 10.

Figure 12 is section XII-XII of figure 1 1.

Figure 13 is section XIII-XIII of figure 1 1 .

BEST WAY OF CARRYING OUT THE INVENTION

With particular reference to the figures, 1 denotes in its entirety a filter group, which is suitable for purifying an air flow from solid particles that may be present in suspension therein. More particularly, the filter group 1 is destined to be located along an intake conduit of an internal combustion engine, such as to filter the comburent air which is supplied internally of the combustion chambers of the engine.

The filter group 1 comprises an outer casing 10, conventionally called the fil- ter box, which in general terms can be made of a plastic or metal material. The casing 10 delimits an internal volume and is provided with an inlet 1 1 for the air to be filtered and an outlet 12 of the filtered air, both communicating with the internal volume. The inlet 1 1 is destined to be in communication with the external environment, while the outlet 12 can be in communication with the combustion chambers of the engine, normally through an intake manifold. Overall the casing 10 has a polyhedric shape, in the present case a polyhedron with an elongate longitudinal axis A.

In the present example, the casing 10 comprises a first substantially beaker- shaped body 13 on a bottom 130 of which (at the bottom in figures 1 and 2) a conduit 31 is realised, having a substantially curved central axis defining the inlet 1 1.

The top of the first body 13 comprises a folded edge 132 defining a surface that is substantially perpendicular to the lateral walls of the first body 13.

The casing 10 further comprises a second body 14 that is also substantially beaker-shaped, on a bottom 140 of which (at the top in figures 1 and 2) a conduit 141 is realised, having a central axis that is substantially inclined with respect to the longitudinal axis A and defining the outlet 12.

The top of the second body 14 comprises a folded edge 142 defining a sur- face that substantially perpendicular to the lateral walls of the first body.

The edge 142 of the second body 14 is destined to face the edge 132 of the first body 13 for substantially airtight closure of the outer casing 10, for example by means of known fixing means such as clamps or the like not shown because of known type.

The outer casing 10 has a substantially quadrangular cross-section (in the example rectangular); however, the section can be any, as well as the arrangement and inclination of the ducts 132 and 142 in the respective bodies, according to the construction requirements.

The filter group 1 comprises a filter cartridge, denoted in its entirety by 20 and 30, respectively in figures 3-8 and in figures 9-13, suitable for mounting internally of the casing 10 such as to sub-divide the internal volume thereof into two separate chambers, the first chamber 15 communicating with the inlet 1 1 and a second chamber 16 communicating with the outlet 12.

In the first embodiment shown in figures 3-8 the filter cartridge 20 comprises a tub-shaped collecting body 21 , suitable for being arranged internally of the casing 10 with a concavity thereof facing the inlet 1 1.

In this case, the collecting body 21 exhibits a truncated pyramid shape having a rectangular base, a base of which (at the bottom in figures 5, 7 and 8) is defined by an open wall 210 suitable for placing the first chamber 15 in communication with the internal volume of the collecting body 21.

The open wall 210 comprises a perimeter edge 21 1 projecting from the collecting body 21 of the conjugated form to the transversal section (with respect to the longitudinal axis A) of the external casing 10, which is destined to be retained in the grip between the edge 132 of the first body 13 and the edge 142 of the second body 14, for example by interposing of an annular seal gasket 212 having a C-shaped transversal section and destined to be frontally secured to the perimeter edge, such that the seal gasket 212 is squeezed between the edge 132 and the edge 142, thus ensuring both a seal for the housing 10 and a hermetic separation between the first chamber 15 of the air to be filtered, and the second chamber 16 of the filtered air.

The collecting body 21 comprises lateral walls 213a and 213b (in the example four in number) that rise from the open wall 210 and a bottom wall 214. In the illustrated example, two of the lateral walls 213a, which face one another, define two respective support flanges and each exhibits a respective rectangular through-opening 215 for passage.

The cartridge 20 thus includes two filter walls 22, in the present example two flat pleated filter walls, which are suitable for intercepting/occluding respectively the two passage openings 215.

The peripheral edge of each filter walls 22 is fixed, e.g. by gluing, to a respective lateral wall 213a at the inner peripheral edge of the passage open- ing 215, which is destined to snugly accommodate the filter wall. The collecting body 21 is then closed laterally by the lateral walls 213b, by the lateral walls 213a and by the filter walls 22 and in an axial direction by the bottom wall 214, while remaining open only at the open wall 210.

In practice, the internal volume of the collecting body 21 , enclosed by the above-described structural elements of the cartridge 20, together with the internal volume of the first body 13 of the housing 10, defines the first chamber 15 when the cartridge 20 is mounted in the mounted configuration thereof. The arrangement of the filter walls 22 in the collecting body 21 may however be different to what is illustrated; also, the shape of the collecting body can be any, according to constructional requirements.

The cartridge 20 further comprises a plurality of separating fins 216 fixed to the lateral walls 213b of the collecting body 21 , which extend in the central area of the collecting body, for example over the whole depth of the collecting body 21 , and are configured such as to divert the flow of air to be filtered from the axial direction toward the two filter walls 22.

In the illustrated example, the separating fins 216 are arranged substantially in a herringbone pattern, as shown in figure 7.

The functioning of the filter group 1 , according to the first embodiment shown in figures 3-8, is as follows.

Once the cartridge 20 has been installed in the casing 10 as described above, and the casing 10 hermetically sealed, the air to be filtered entering from the inlet 1 1 into the first chamber 15 is conveyed axially into the internal volume of the collecting body 21.

The separating fins 216 deflect the air flow in a transversal direction to the fil- ter walls 22 such as to aid the separation of particulate and any water molecules present in the air to be filtered therefrom.

The air to be filtered then passes through the filter walls 22 from inside the collecting body 21 towards the outside thereof, depositing the particulate on the inner wall (with respect to the collecting body 21 ) thereof.

The filtered air then passes into the second chamber 16 and from there to the exit 12 from which is supplied to the internal combustion engine. Should it be necessary to replace the cartridge 20, the housing 10 is opened and the cartridge removed. Note that during this step the possible detachment of particulate matter from the inner surface of the filter walls 22, and from the inner walls of the collection chamber 21 which surrounds them, is not such as to involve the second chamber 16, as all of the particulate remains still contained in safety within the collecting body 21.

In the second embodiment shown in figures 10-13 the filter cartridge 30 comprises a collecting body 31 shaped as a tub, adapted to be disposed within the casing 10 with its concavity facing the inlet 1 1 .

In the illustrated example, the collecting body 31 has a parallelepiped shape with a rectangular base, the base of which (at bottom in figure 12) is defined by an open wall 310 which can place the first chamber 15 in communication with the internal volume of the collecting body 31.

The open wall 310 comprises a perimeter edge 31 1 , projecting from the col- lecting body 31 and having a complementary shape to the cross section (with respect to the longitudinal axis A) of the outer casing 10, which is destined to be retained in a grip between the edge 132 of the first body 13 and the edge 142 of the second body 14, for example by interposing of a seal gasket 312 of annular shape and having a C-shaped cross section destined to be se- cured frontally to the peripheral edge, such that the gasket 312 is squeezed between the edge 132 and the edge 142, ensuring a sealing of the housing 10 and guaranteeing the hermetic separation between the first chamber 15 of the air to be filtered, and the second chamber 16 of the filtered air.

The collecting body 31 comprises, then, lateral walls 313 (in the example four in number) which rise from the open wall 310 and a bottom wall 314 which superiorly closes (with reference to the figure) the collecting body 31.

The bottom wall 314 defines a support flange and exhibits a plurality circular though-openings 315 for passage.

The cartridge 30 further comprises a plurality of tubular filtering sections 32 (in the example 1 1 in number), each of which has a closed end and an opposite open end which is fixed to the support flange, or to the bottom wall 314, for example by gluing. At each filter wall 32, the bottom wall 314 is provided with a passage opening 315 that leads into the inner cavity of the filter wall 32.

For example, the opening 315 may be delimited by a projecting shank (not shown) facing toward the inside of the collecting body 31 , which shank snugly inserts internally of the relative filter wall 32, so as to improve the fixing thereof.

The collecting body 31 is then laterally closed by the lateral walls 313 and in the axial direction by the bottom wall 314 and by the filter walls 32, remaining open only at the open wall 310.

In practice, the internal volume of the collecting body 31 , enclosed by the above structural elements of the cartridge 30, together with the internal volume of the first body 13 of the casing 10 defines the first chamber 15, when the cartridge 30 is mounted in the casing.

However, the arrangement of the filtering baffles 32 in the collecting body 31 can be different than that illustrated; also the shape of the collecting body can be any, according to constructional requirements.

The cartridge 30 also comprises a plurality of separating fins 316 fixed to the lateral walls 313 of the collecting body 31 , for example at the open wall 310, and configured so as to divert the flow of air to be filtered from the axial direc- tion towards the filter walls 32.

In the example shown the separating fins are arranged on two opposing lateral walls 313 so as to converge the air towards the centre of the collecting body 31 , as shown in figures 10 and 13 and drop the solid particulate towards a lateral wall 313 of the collecting body 31.

The functioning of the filter group 1 , according to this second embodiment shown in figures 9-13, is as follows.

Once the cartridge 30 has been installed in the casing 0 as described above and the casing 10 hermetically sealed, the air to be filtered entering from the inlet 1 1 in the first chamber 15 is conveyed axially inside the internal volume of the collecting body 31. The separating fins 316 deflect the air flow in a transversal direction to the filter walls 32 while at the same time aiding the separation of the particulate and any water molecules present in the air to be filtered from the air itself. The air to be filtered then passes through the filter wall 32 from the outside towards the inside, and deposits the particulate on the outer wall thereof. The filtered air axially passes through the inner cavity of the filter walls 32 (as shown in figure 12) and reaches the second chamber 16, through the passage openings 315, then passing from the outlet 12 from which it is conveyed to the internal combustion engine.

Should it be necessary to replace the cartridge 30, the casing 10 is opened and the cartridge removed. Note that during this step the possible detachment of particulate matter from the outer surface of the filter walls 32, as well as from the internal walls of the collection chamber 31 which surrounds them, is not such as to involve the second chamber 16, as all of the particulate re- mains safely contained in the collecting body 31 .

The invention thus conceived is susceptible of numerous modifications and variations, all within the inventive concept.

For example, the filter walls 22 and 32, which in the embodiments shown above are more than one and are crossed in parallel by the air to be filtered, can in different configurations of the filter group 1 be one for each embodiment or may be multiple, and be crossed in series (or in parallel and series combined) by the air to be filtered according to the manufacturing requirements and the degree of filtration required.

Moreover all details can be replaced with other technically-equivalent ele- ments.

In practice the materials used, as well as the shapes and dimensions, may be any according to requirements without thereby abandoning the ambit of protection of the appended claims.

Claims

1. A filter cartridge (20, 30), suitable for being contained internally of an external casing (10) provided with an inlet (1 1 ) and an outlet (12) such as to filter the fluid which flows from the inlet (1 1 ) towards the outlet (12), which filter cartridge (20, 30) comprises at least a filter wall (22, 32) and a support flange (213a, 314) fixed to the filter wall (22, 32) and destined to sub-divide the internal volume of the casing (10) into a first chamber (15) communicating with the inlet (1 1 ) and a second chamber (16) communicating with the outlet (12), in communication with one another via the filter wall (22, 32), at least a collecting body (21 , 31 ) associated to the support flange (213a, 314) and destined to define a collecting volume communicating with the first chamber (15) such as to collect the particulate separating from the fluid to be filtered, wherein the collecting body (21 , 31 ) is conformed substantially as a tray and is provided with an open wall (210, 310) suitable for setting the first chamber (15) in communication with the internal volume of the collecting body (21 , 31 ), said support flange (213a, 314) defining at least a wall of the collecting body (21 ,31 ) and delimiting a passage opening (215, 315) suitable for setting the internal volume of the tray-shaped collecting body (21 ,31 ) in communication with the external volume thereof, characterized in that the filter wall (22,32) is directly fixed to the entire peripheral edge of the passage opening (215,315), such as the passage opening (215,315) be occluded by said filter wall (22,32).

2. The cartridge (20, 30) of claim 1 , wherein the collecting body (21 , 31 ) is realised in a single piece with the support flange (213a, 314).

3. The cartridge (20, 30) of claim 1 , wherein at least one from the support flange (213a, 314) and the collecting body (21 ,31 ) comprises at least a perimeter edge (21 1 , 31 1 ) to which a seal (212, 312) is fixed that is suitable for being associated to the casing (10) for sealedly separating between the first chamber (15) and the second chamber (16).

4. The cartridge (20, 30) of claim 1 , characterised in that it comprises separating tabs (216, 316) associated to the collecting body (21 , 31 ) and suitable for conveying the fluid to be filtered towards the filter wall (22, 32).

5. The cartridge (20, 30) of claim 1 , wherein the filter wall (32) is a tubular wall.

6. The cartridge (20, 30) of claim 1 , wherein the filter wall (22) is a pleated wall.

7. A filter group (1 ) for an internal combustion engine, characterised in that it comprises an external casing (10) provided with an inlet (1 1 ) and an outlet

(12) and a filter cartridge (20, 30), according to any one of the preceding claims, located internally of the casing ( 0) in such a way as to filter the fluid that flows from the inlet (1 1 ) towards the outlet (12).

8. The group (1 ) of claim 7, wherein the casing (10) comprises a first body

(13) in which the inlet (1 1) is defined and a second body (14) in which the outlet (12) is defined, the seal (212, 312) being suitable for being interposed between the first body (14) and the second body (14) of the casing (10) for sealed separating between the first chamber (15) and the second chamber (16).