"FLUID FILTRATION ASSEMBLY"

Field of application

[0001]The present invention relates to a filtration assembly of a fluid, preferably fuel, preferably diesel. In addition, the present invention relates to a fuel system of a vehicle comprising said filtration assembly. Lastly, the present invention relates to the assembly method of said filtration assembly. [0002]The present invention finds its preferred application in the automotive sector. Specifically, in fact, the context in which the present invention lies is that of fluid filtration assemblies, in particular of vehicle fuel, preferably diesel. [0003]Filtration assemblies typically comprising a cup (or tank) and a head group coupling to each other in an integral manner are known of in the prior art. The filtration assemblies are therefore suitable to be fluidically connected to the vehicle's fuel system, i.e. the cup and said head group are in turn fluidically connected to the vehicle's fuel system. In other words, fluid, preferably fuel, enters the known filtration assemblies to be filtered (dirty) and fluid, preferably filtered (clean) fuel, comes out of them. In particular the cup and the head group are specially designed to house within them a filter element suitable to carry out specific filtration operations when the fluid passes through it, for example of solid particulate matter and/or liquid particulate substances, such as water. [0004]The main problem of the prior filtration assemblies consists of the complex coupling methods between the various components mentioned above.

[0005]In the presence of the complex coupling methods of the various components, the assembly (and similarly disassembly) operations of the fluid filtration assembly itself are particularly complex. This problem is therefore particularly felt, negatively influencing the maintenance operations of the filtration assembly and in particular the replacement of the filter cartridge. Solution according to the invention

[0006]The need is therefore strongly felt to provide a filtration assembly which overcomes the aforesaid problem typical of the prior art. In other words, the need is strongly felt to provide a filtration assembly which is simple to assemble and disassemble. That is to say, the need is strongly felt to provide a filtration assembly in which maintenance operations are extremely simplified. [0007]Such purpose is achieved by the filtration assembly claimed in claim 1. In addition, such purpose is also achieved by means of the fuel system comprising said filtration assembly according to claim 17. In addition such purpose is also achieved by the assembly method of a filtration assembly according to claim 18. The claims dependent on these show preferred embodiments involving further advantageous aspects.

Description of the drawings

[0008]Further characteristics and advantages of the invention will, in any case, be evident from the description given below of its preferred embodiments, made by way of a non-limiting example with reference to the appended drawings, wherein:

[0009]- figure 1 shows a filtration assembly in perspective, in cross-section, in separate parts according to the present invention, in a preferred embodiment;

[0010]- figures 2 and 2' show in cross-section respectively a perspective view and a longitudinal view of the filtration assembly shown in figure 1 in an assembled configuration; [0011]- figures 3a and 3b show, respectively, in a perspective view from below and in a perspective view from above, a head group and a filter cartridge included in the filtration assembly shown in figure 1;

[0012]- figure 4 shows a filtration assembly in perspective in cross-section in separate parts according to the present invention in a further preferred embodiment;

[0013]- figure 5 shows a perspective view in cross-section of the filtration assembly shown in figure 4 in an assembled configuration;

[0014]- figures 6a and 6b show, respectively, in a perspective view from below and in a perspective view from above, a head group and a filter cartridge included in the filtration assembly shown in figure 4. Detailed Description

[0015]In the appended drawings, reference numeral 1 denotes a filtration assembly of a fluid, preferably fuel, preferably diesel, according to the present invention. [0016]The filtration assembly 1 of the present invention is in fact suitable to be part of a vehicle fuel system in which the fluid flows. Preferably, the fuel system is specifically designed to supply fuel to the engine group of the vehicle and therefore the filtration assembly 1 is suitable to filter fuel.

[0017]In particular, the filtration assembly 1 is suitable to filter unwanted suspended particles from the fluid. [0018]According to one embodiment variant, the filtration assembly 1 is suitable to separate other undesired liquids suspended in the fluid to be filtered, such as water, from the fluid, preferably from the fuel.

[0019]According to the present invention, the filtration assembly 1 of a fluid extends along a main axis X-X.

[0020]In this description, when referring to the axial dimension, reference is made to a dimension corresponding to or parallel to the main axis X-X; in addition, when referring to a circumferential or annular dimension, reference is made to a dimension extending on a circumference concentric to the main axis X-X; in addition, when referring to a radial dimension, reference is made to a dimension extending in a radial direction with respect to the main axis X-X; furthermore, when referring to a tangential dimension, reference is made to a dimension tangential to a circumference concentric to the main axis X-X; lastly, when referring to a transverse dimension, reference is made to a dimension orthogonal to the main axis X-X.

[0021]According to the present invention, the filtration assembly 1 comprises a head group 2 that is fluidically connectable to the ducts of the fuel system. In particular, the head group 2 is fluidically connected to a system inlet duct in which the fluid to be filtered flows and to a system outlet duct in which the filtered fluid flows. [0022]According to a preferred embodiment, the head group 2 comprises a group inlet mouth 21 and a group outlet mouth 22 through which the fluid flows respectively in input and in output.

[0023]According to a preferred embodiment, the head group 2 comprises said group inlet mouth 21 and said group outlet mouth 22 in the form of nozzles.

[0024]According to the present invention, the filtration assembly 1 comprises a filter cartridge 3 that is engageable integrally and fluidically to the head group 2. In other words, assembling the filtration assembly 1 by joining the head group 2 to the filter cartridge 3 the fluid flowing in the latter is subject to filtration operations .

[0025]According to the present invention, the filter cartridge 3 comprises a filter element 4 comprising a filter media 40 which is crossable by the fluid.

[0026]According to a preferred embodiment, the filter media 40 is crossable axially.

[0027]According to a further preferred embodiment, the filter media 40 is of the tubular type and is crossable by the fluid radially. Preferably it is crossable by the fluid from the inside to the outside.

[0028]According to a preferred embodiment the filter media

40 is made of a synthetic material (e.g. PA6, PA66, PBT PET, etc.) cellulose material or a combination of the two. Preferably, in a preferred embodiment, the filter media 40 comprises the presence of glass fibres.

[0029]According to the present invention, the filter cartridge 3 comprises a cup 5 and a cover 6 that is joinable to define a housing in which the filter element 4 is placed.

[0030]Preferably, the cup 5 is shaped in such a way that it transversely defines, with a back wall, and laterally with side walls, a housing region. [0031]The cup 5 comprises a housing chamber 50 in which the filter element 4 is housed, wherein said housing chamber 50 is open at an axial end comprising a head edge 51. Preferably, the cup 5 comprises the housing chamber 50 in its entirety. Preferably, the cup 5 comprises a portion of the housing chamber 50 in its entirety.

[0032]According to the present invention the cup 5 is engageable to the head group 2 by means of rotational operations .

[0033]In fact, the cup 5 comprises cup engagement means 55 and the head group 2 comprises head engagement means 25. Said cup engagement means 55 and said head engagement means 25 are mutually engageable by means of rotation operations. Preferably, these rotation operations also involve a reciprocal axial movement at the same time. [0034]According to a preferred embodiment the head engagement means 25 comprise an engagement collar 250 and the cup engagement means 55 comprise a cup collar 550. Preferably the two collars are specially shaped to mutually engage in rotation involving an axial translation of the components, the cup 5 and the head group 2, which they are part of.

[0035]In other words, the cup 5 and head group 2 join together in a rototranslation.

[0036]According to a preferred embodiment, the engagement collar 250 comprises a fastening portion and the cup collar 550 comprises a fastening portion, the mutual engagement of which in a rotational direction involves reciprocal movement in rototranslation.

[0037]According to a preferred embodiment, the engagement collar 250 comprises a threaded portion and the cup collar 550 in turn comprises a threaded portion.

Preferably, the pitch of the aforesaid threaded portion is such that it is gradually moved axially.

[0038]According to a preferred embodiment, the engagement collar 250 is suitable to receive the cup collar 550.

[0039]According to a preferred embodiment, the engagement collar 250 and the cup collar 550 are specially shaped in such a way as to present, at least one of the two, a first portion 255, 555 with axial insertion and a second fastening portion, as described above. [0040]According to a preferred embodiment, the engagement collar 250 and/or the cup collar 550 comprise an abutment step 551 suitable to act as an axial stop to the reciprocal axial movement between the head group 2 and cup 5 to a further axial translation.

[0041]According to a preferred embodiment, the filter cartridge 3 comprises a cover 6 that is engageable to the cup 5 at the head edge 51. In other words, the cover 6 delimits the top of the housing chamber 50. [0042]Preferably, the cover 6 comprises a filter inlet mouth 61 and a filter outlet mouth 62 positioned in a radial position between the main axis X-X through which it flows in and out of the cartridge. Preferably, one out of the filter inlet mouth 61 and outlet mouth 62 is positioned at the main axis X-X.

[0043]In particular, the cover 6 is engageable in an axial direction with the head edge 51 and is rotationally free with respect to the cup 5. In other words, the head edge 51 is suitable to transmit an axial action to the cover 6. Preferably, the head edge 51 engages the cover 6 directly. According to one embodiment variant, described below, the cover 6 is engaged to the head edge 51 indirectly (i.e. via another component in the filter cartridge 3). [0044]In other words, the cover 6 is fixable axially to the cup 5, but at the same time it is free to rotate with respect to the main axis X-X. In other words, in the assembled condition of the filter cartridge 3, the cover 6 is fixed axially to the cup 5, preferably to the head edge 51, while remaining free to rotate with respect to the axis X-X. That is to say, the cover 6 is only allowed to move along the X - X axis during the rotational coupling operations of the cup 5 and head group 2 [0045]According to the present invention, in addition, the cover 6 is integrally connected to the filter element 4. That is to say, that the movements to which the cover 6 is subject with respect to the cup 5 and/or with respect to the head group 2 are the same operations to which the filtering element 4 is subject. In other words, a specific axial or angular position of the cover 6 corresponds to a specific axial or angular position of the filter element 4.

[0046]According to a preferred embodiment, the cover 6 is integral with the filter element 4. In other words, the cover 6 corresponds to the upper plate of the filter element 4; preferably the cover 6 is for example directly joined to the filter media 40.

[0047]According to an embodiment variant, the cover 6 is mountable integrally to the filter element 4. That is to say that the filter element 4 comprises at least one end plate suitable for being fitted integrally to the cover 6 at an axial end thereof.

[0048]According to the present invention, the cover 6 comprises an axial annular gasket 60 suitable to sealingly engage in an axial direction the head group 2 in the engagement operations between the cup engagement means 55 and the head engagement means 25. That is to say, that with the filtration assembly 3 assembled, the axial annular gasket 60 is tightened in an axial direction on the head group 2.

[0049]Preferably, therefore, the axial annular gasket 60 is intended to engage the head group 2 in an axial direction in order to provide a barrier to the filtration region inside the filter cartridge 3 and the external environment .

[0050]In particular, the head group 2 comprises a head wall 20, preferably flat, on which the axial annular gasket 60 is engageable.

[0051]Preferably, the axial annular gasket 60 is in a material chosen from the family of elastomeric materials (e.g. FPM, FKM, FFKM, VMQ, FVMQ, HNBR, NBR, AEM, ACM,

EDPM etc.) having a chemical composition suitable to guarantee a correct chemical and physical resistance in contact with the working fluid. [0052]According to a preferred embodiment, the axial annular gasket 60 is positioned at an axial gasket radial distance Ra from the main axis X-X.

[0053]According to the present invention, in addition, the cover 6 also comprises a radial annular gasket 65 suitable for carrying out a radial sealing engagement.

[0054]According to the present invention, the axial annular gasket 60 and radial annular gasket 65 are suitable to sealingly separate the filtration region of the filter cartridge 3, engaged with the head group 2, from the outside environment.

[0055]Specifically, said radial annular gasket 65 is suitable for sealing in a radial direction allowing the rotary movement of the cover 6 with respect to the main axis X-X. Preferably, the radial annular gasket 65 is suitable to perform a sealing action in a radial direction allowing the rotary movement of the cover 6 around the X-X axis with respect to the cup 5.

[0056]Preferably, the radial annular gasket 65 is in a material chosen from the family of elastomeric materials (e.g. FPM, FKM, FFKM, VMQ, FVMQ, HNBR, NBR, AEM, ACM,

EDPM etc.) having a chemical composition suitable to guarantee a correct chemical and physical resistance in contact with the working fluid.

[0057]According to a preferred embodiment, the radial annular gasket 65 is positioned at a radial gasket radial distance Rr from the main axis X-X.

[0058]Preferably, the axial gasket radial distance Ra is less than the radial gasket radial distance Rr.

[0059]According to the present invention, in addition, the head group 2 comprises a pin element 29 that protrudes axially substantially parallel to the main axis X-X and the cover 6 comprises a slot 69 specially shaped to accommodate said pin element 29.

[0060]According to the present invention, with the pin element 29 inserted in the slot 69, the head group 2 and the cover 6 mutually positionable in a unique angular position. According to the present invention, during the assembly operations of the filter cartridge 3 to the head group 2, thanks to the engagement between the pin element 29 and slot 69, the cover 6 and the filter element 4 remain fixed in a predetermined angular position, while the cup 5 is subject to the rotating locking operations that involve the axial juxtaposition of the filter cartridge 3 to the head group 2 and the consequent tightening of the axial annular gasket 60 (and the fastening of the cup 5, and therefore of the cartridge 3, to the head group 2).

[0061]According to a preferred embodiment, said pin element 29 protrudes from said head wall 20. [0062]According to a preferred embodiment, the pin element 29 comprises a tip 29' distal from the head wall 20.

[0063]Preferably, the pin element 29 has a tapered shape proximal to the tip 29'.

[0064]According to a preferred embodiment, the pin element 29 comprises at least one sliding wall or edge 291, preferably two sliding walls or edges 291, inclined in such a way that it is suitable for easy insertion of the pin element 29 into the slot 69.

[0065]According to a preferred embodiment, the pin element 29 comprises a side wall 290, preferably having a circumferential or tangential extension to the main axis X-X, and a radial wall 295, preferably having a radial extension to the main axis X-X.

[0066]According to a preferred embodiment, the slot 69 is substantially complementary to the cross-section of the pin element 29 comprising a side portion 690 and a radial portion 695.

[0067]In other words, the cross-section of the pin element 29 is basically T-shaped. Similarly, the slot 69 in turn defines a substantially T-shaped housing area.

[0068]According to a preferred embodiment, the pin element 29 is housed in the slot 69 maintaining "clearance" (i.e. the slot 69 is slightly larger than the pin element 29).

Preferably, for an effective coupling between the cup 5 and the head group 2 there is no clearance in the circumferential/tangential direction according to which the locking rotation between the two components is performed.

[0069]According to a preferred embodiment, the slot 69 is a through hole.

[0070]According to a preferred embodiment, the slot 69 is a recess made on the cover 6 suitable to accommodate the pin element 29.

[0071]According to a preferred embodiment, the pin element 29 extends axially with respect to the main axis X-X for an axial length so that in the assembly operations, first the insertion of the pin element 29 into the slot 69 is carried out and then the rotary operations to lock the filter cartridge 3 to the head group 2. [0072]According to a preferred embodiment, the pin element

29 extends axially with respect to the main axis X-X so that the tip 29' is in such a position that it is radially (i.e. on a transverse plane) at least facing the fastening portion of the engagement collar 250. For example, according to a preferred embodiment, the pin element 29 extends axially until it has its tip 29' radially facing the threaded portion.

[0073]According to a further preferred embodiment, the pin element 29 extends axially with respect to the axis X-X in such a way to have the tip 29' in a position that it is radially (i.e. on a transverse plane) higher than the engagement portion. For example, according to a preferred embodiment, the pin element 29 extends axially until it has its tip 29' in a higher position at the beginning of the threaded portion.

[0074]According to a preferred embodiment, the pin element 29 (and similarly the slot 69) is positioned at a radial pin distance (Rs) from the main axis (X-X).

[0075]Preferably, the radial pin distance Rs is less than the axial gasket radial distance Ra.

[0076]Preferably, the radial pin distance Rs is less than the radial gasket radial distance Rr and the axial gasket radial distance Ra.

[0077]According to a preferred embodiment, the filter element 4 comprises water separation means, suitable for separating any water particles in the fluid to be filtered in such a way as to collect water in a region proximal to the bottom of the cup 5, in other words proximal to the bottom wall. [0078]According to such embodiment, the head group 2 comprises a water drainage mouth 27 and the cover 6 a water drainage section 67 suitable to fluidically connect to the water drainage mouth 27. Preferably, the water drainage section 67 extends parallel to the main axis X-X to fit axially inside the water drainage mouth 27. [0079]According to a preferred embodiment, the filter cartridge 3 also comprises a drainage cannula 7 suitable to extend in an axial direction from the cover 6 towards the bottom of the cup 5. [0080]According to a preferred embodiment, the drainage section 67 is located in a region opposite the main axis X-X where the slot 69 is located. Preferably, the slot 69 and drainage section 67 are each placed in a respective half. [0081]According to a preferred embodiment, the drainage section 67 is positioned at a radial drainage distance Rd from the main axis X-X.

[0082]Preferably, the radial drainage distance Rd is less than the axial gasket radial distance Ra. [0083]Preferably, the radial drainage distance Rd is less than the radial gasket radial distance Rr and the axial gasket radial distance Ra.

[0084]According to a first preferred embodiment, the cover 6 radially sealingly engages the side wall of the cup 5 by means of the radial annular gasket 65. Preferably, the radial annular gasket 65 radially sealingly engages the side wall of the cup 5 in a region proximal to the head edge 51.

[0085]Preferably, the radial annular gasket 65 radially sealingly engages the side wall of the cup 5 leaving the cover 6 free to rotate with respect to the axis X-X.

[0086]According to a further embodiment, the filter cartridge 3 comprises an auxiliary cup 8 defining a filtration chamber 80. Preferably, the filter element 4 is housed in said auxiliary cup 8. Preferably, the auxiliary cup 8 is in turn housed in the cup 5. According to an embodiment variant, the auxiliary cup 8 has a substantially complementary shape to the cup 5.

[0087]According to such embodiment, the cover 6 radially sealingly engages said auxiliary cup 8 by means of the radial annular gasket 65. Preferably, the radial annular gasket 65 radially sealingly engages the side wall of the auxiliary cup 8. Preferably, the radial annular gasket 65 radially sealingly engages the side wall of the auxiliary cup 8 in a region proximal to the auxiliary head edge 81. [0088]Preferably, the radial annular gasket 65 radially sealingly engages the side wall of the auxiliary cup 8, leaving the cover 6 free to rotate with respect to the axis X-X. [0089]According to a preferred embodiment, the auxiliary cup 8 has a shape such as to comprise an abutment, preferably annular, that engages the head edge 51. Preferably, the axial thrust action of the head edge 51 is discharged onto said abutment and thus onto said cover 6. [0090]According to a preferred embodiment, the auxiliary cup 8 is shaped so that it is rotationally locked in relation to the cup 5. In other words, when said auxiliary cup 8 is present, the cover 6 is free to rotate with respect to said auxiliary cup 8 which in turn remains fixed with respect to the cup 5.

[0091]According to a preferred embodiment, the cover 6 is made of a material chosen from the family of plastics. [0092]Preferably, the cover 6 is made by a moulding process. Preferably, at the annular gaskets, the cover comprises specific annular housing slots.

[0093]According to a preferred embodiment, the axial annular gasket 60 and the radial annular gasket 65 are positioned on two axially opposite sides of the cover 6. [0094]As said, the present embodiment also relates to a vehicle fuel system comprising a filtration assembly 1 of a fluid, preferably fuel, preferably diesel, with the characteristics described above.

[0095]In addition, the present invention also relates to a method of assembling a filtration assembly with the characteristics described above. In particular, in the first step of said assembly method, the filter cartridge 3 is assembled by axially inserting the assembly comprising the filter element 4 and the cover 6, joined together, into the cup 5 until the cover 6 axially engages the head edge of the cup 5.

[0096]In addition, the assembly method provides for a second step of the assembly of the filter cartridge 3 with the head group 2, in which the following steps are performed:

[0097]- axial juxtaposition of the filter cartridge 3 and head group 2 so as to insert the pin element 29 into the slot 69;

[0098]- performance of rotary engagement operations between the filter cartridge 3 and head group 2 so as to allow reciprocal rotation between the cup 4 and head group 2.

[0099]Innovatively, the filtration assembly of a fluid described above fully absolves the purpose of the present invention overcoming the drawbacks typical of the prior art. Innovatively, the fuel system of a vehicle comprising the filtration assembly fully absolves the purpose of the present invention overcoming the drawbacks typical of the prior art. Innovatively, the assembly method of the filtration assembly also fully satisfies the purpose of the present invention overcoming the drawbacks typical of the prior art.

[00100] Advantageously, the filtration assembly has features that make assembly and disassembly operations safe and foolproof. [00101] Advantageously, the problem of possible adhesion of the seals to the walls with which they cooperate, which typically hinder the disassembly of the filter cartridge, is overcome. Advantageously, the pin element makes it easier and more convenient to detach the axial annular gasket from the head group during rotational disassembly operations.

[00102] Advantageously, the filtration assembly, particularly in the reciprocal engagement of the filter cartridge and head group, has effective sealing regions.

[00103] Advantageously, the filtration assembly comprises an axial annular gasket suitable to effectively engage the head group.

[00104] Advantageously, the axial gasket is fitted on a cover that is rotatable with respect to the tank and objectified by means of appropriate objectification elements, ensuring a clamping action on the axial gasket acting in the direction parallel to the axis.

[00105] Advantageously, the axial annular gasket is tightened with only axial motion of the cover, in the axial direction only, minimising particularly harmful unwanted friction in the case of annular gaskets designed to form hydraulic seals to the environment.

[00106] Advantageously, the axial annular gasket operates exclusively in the axial direction. Advantageously, the axial annular gasket is not subject to circumferential rubbing actions. Advantageously, the axial annular gasket is dimensioned in relation to the fact that it operates exclusively in the axial direction. [00107] Advantageously, the filter cartridge 3 is suitable for "clean" maintenance operations, collecting the dirt inside it. Advantageously, the leakage of fluid and dirt collected in the cup body is minimised thanks to the axial position of the axial annular gasket. [00108] Advantageously, since the filter element is housed in the filter cartridge, direct interactions on the filter media are minimised, limiting possible damage and contamination.

[00109] Advantageously, the cover is producible by simple moulding operations.

[00110] It is clear that a person skilled in the art may make modifications to the present invention so as to satisfy contingent requirements, all contained within the scope of protection as defined by the following claims. List of reference numbers:

[00111]

1 fluid filtration assembly X-X main axis

2 head group 20 head wall 21 group inlet mouth

22 group outlet mouth 25 head engagement means 250 engagement collar 255 first axial insertion portion

27 drainage mouth 29 pin element 29' tip 290 side wall 291 sliding wall or edge

295 radial wall

3 filter cartridge

4 filter element 40 filter media 5 cup

50 housing chamber

51 head edge

55 cup engagement means 550 cup collar 551 abutment step

555 first axial insertion portion 6 cover

60 axial annular gasket

61 filter inlet mouth 62 filter outlet mouth 65 radial annular gasket

67 water drainage section 69 slot

690 side portion 695 radial portion

7 drainage cannula

8 auxiliary cup

81 auxiliary head edge Rs pin radial distance Ra axial gasket radial distance Rr radial gasket radial distance

Rd drainage radial distance