WO2018025228A1

WO2018025228A1 - Cartridge assembly with contact annular element

Info

Publication number: WO2018025228A1
Application number: PCT/IB2017/054777
Authority: WO
Inventors: Giorgio Girondi
Original assignee: Ufi Innovation Center S.R.L.
Priority date: 2016-08-05
Filing date: 2017-08-04
Publication date: 2018-02-08
Also published as: IT201600082909A1

Abstract

A cartridge assembly (10) for a filtration assembly of a fluid (1) comprises a filter cartridge (100) having a main axis (X-X). The filter cartridge (100) comprises a filter medium (110) defining a cavity (110') and is traversed by the fluid from the inside outwards. The filter medium (110) comprises a plurality of filter layers (111, 112) comprising a first electrically conductive layer (111), to control the temperature thereof so as to heat the fluid traversing it, facing the cavity (110'). The cartridge assembly (10) comprises at least one separate annular element (10), elastically yielding, housed in the cavity (110') in a contact configuration in which it performs a radial contact action on the first layer (111) identifying an electrical contact between the annular element (150) and the first layer (111).

Description

DESCRIPTION

"Cartridge assembly with contact annular element"

Field of application

[0001] The present invention relates to a cartridge assembly for a filtration assembly of a fluid, and a candle element for a filtration assembly of a fluid adapted to operate with said cartridge assembly. Moreover, the present invention relates to a fluid filtration assembly comprising said cartridge assembly and said candle element.

[0002] Preferably, the fluid filtration assembly substantially falls within the automotive field. Preferably, the filtration assembly is adapted to perform the filtration of fuel, preferably diesel. In other embodiments, the filtration assembly is adapted to perform the filtration of oil. Moreover, in further embodiments, the filtration assembly is adapted to filter air, such as blow-by gases.

[0003] In other words, the definition of "fluid" refers to both a liquid type of fluid, such as fuel or oil, and to a gaseous type of fluid, such as air or blow-by gases.

[0004] The main problem in fluid filtration in particular is the occurrence, more or less sudden, of the accumulation on the first layer of filter medium traversed by the fluid, resulting in the blockage of the filter medium. This situation is particularly acute when the fluid is at low temperatures, such as when the engine is turned on, or in extremely cold weather conditions.

[0005] In fact, at low temperatures, the diesel fuel contains a large amount of paraffin. Or still, at low temperature, the blow-by gas contains condensate. Or moreover, at low temperatures, air contains ice crystals.

[0006] In order to overcome this problem, in the prior art it is known to heat the fluid, thereby reducing or avoiding the adverse effects due to the presence of paraffin crystals, or condensate, or ice.

[0007] Solutions of filtration assemblies are, in fact, provided in which the first layer of the filter medium comprised therein is heatable, preferably electrically, in such a manner as to in turn heat the fuel traversing it.

[0008] The main problem of these solutions of filtration assemblies is to bring the electric supply to said first layer of the filter medium to control it in heating, when required.

[0009] Typically, this need involves the design and production of filter cartridges with particularly complex geometries; for example, embodiments are known in which the end plates of the filter cartridge are provided, sometimes co-moulded, with special electrical contacts adapted to put the respective first layer of the filter medium in contact with the external electric supply.

[0010] This problem is even more felt if the dimensions of the filter cartridge are limited, and the space proximal to said first layer is limited. Specifically, for example, this problem is particularly felt in the embodiments in which the filter cartridge is of the cylindrical type and is traversed by the fluid from inside outwards, thus having said first electrically heatable layer located inside the inner cavity of the filter cartridge.

[0011] An example of an embodiment of a filtration assembly exhibiting such a drawback is shown in document DE102009005550.

Solution of the invention

[0012] The need to provide a cartridge assembly having a filter medium with a first electrically heated layer, in order to control the temperature thereof according to the needs, having a simple electric supply mode, is therefore strongly felt. In other words, the need for a cartridge assembly provided with the first layer of the filter medium that is electrically heated, with a simple geometry and simple assembly and production methods compared to the typical prior art solutions is particularly felt. [0013] The object of the present invention is to provide a cartridge assembly, a candle element and a filtration assembly in which the above need is met and the needs of the specific application field are also effectively and efficiently met. In other words, the object of the present invention is to provide a cartridge assembly, a candle element and a filtration assembly in which the temperature of the first layer of the filter medium is adjustable, being effectively and efficiently electrically powered and controlled.

[0014] This object is achieved by the cartridge assembly claimed in claim 1, by a candle element according to claim 12 and by a filtration assembly comprising the cartridge element according to claim 16. Likewise, this object is also achieved by a method of producing and assembling a cartridge assembly according to claim 18 and by a method of producing and assembling a filtration assembly according to claim 19. The dependent claims describe preferred embodiment variants involving further advantageous aspects.

Description of the drawings

[0015] Further features and advantages of the invention will be made readily apparent from the following description of preferred embodiment examples thereof, provided purely by way of a non-limiting example, with reference to the accompanying figures, in which:

[0016] - figure 1 shows a perspective view with separate parts of the filtration assembly according to a preferred embodiment, object of the present invention;

[0017] - figure la shows a longitudinal sectional view with separate parts of the filtration assembly shown in figure 1;

[0018] - figure 2 shows a longitudinal sectional view of the filtration assembly in figure 1, assembled;

[0019] - figure 3 shows a longitudinal sectional view of the filtration assembly in a first insertion configuration of a cartridge assembly on a candle element ;

[0020] - figure 3' shows a cross section of the cartridge assembly along plane V-V in figure 3;

[0021] - figure 4 shows a longitudinal sectional view of the filtration assembly in a second insertion configuration of a cartridge assembly on a candle element, in which the cartridge assembly has completed the axial insertion;

[0022] - figure 4' shows a cross section of the cartridge assembly along plane VI-VI in figure 4;

[0023] - figure 5 shows a longitudinal sectional view of the filtration assembly in a third insertion configuration of a cartridge assembly on a candle element, in which the cartridge assembly has completed its rotation with respect to the candle element;

[0024] - figure 5' shows a cross section of the cartridge assembly along plane VII-VII in figure 5;

[0025] - figure 6 shows a longitudinal sectional view of a cartridge assembly object of the present invention according to a preferred embodiment, in an embodiment variant ;

[0026] - figure 7 shows a perspective view with separate parts of the cartridge assembly in figure 6;

[0027] - figure 8 shows a perspective view of the annular element comprised in a cartridge assembly, in a preferred embodiment ;

[0028] - figure 9 shows a front view of a candle element comprised in a cartridge assembly, in a preferred embodiment, object of the present invention;

[0029]- figures 9', 9'', 9''' show a sectional view along plane IX-IX shown in figure 9, and two enlarged views of some details of the candle element in figure 9, respectively.

Detailed description

[0030] In the accompanying figures, reference numeral 1 denotes a filtration assembly according to an embodiment of the present invention. Moreover, reference numeral 10 denotes a cartridge assembly for a filtration assembly 1 according to a preferred embodiment of the present invention. Moreover, reference numeral 20 denotes a candle element for a filtration assembly 1 according to a preferred embodiment of the present invention.

[0031] The cartridge assembly 10 is specific for filtering a fluid. Preferably, the cartridge assembly 10 object of the present invention is adapted to be used in a filtration assembly specific for the automotive field. In a first embodiment, the cartridge assembly is adapted for filtering fuel, preferably diesel. In further embodiments, the cartridge assembly 10 is also adapted to be used in a filtration assembly of urea. Further embodiments of the cartridge assembly are adapted to allow the filtration of oil, air and blow-by gases.

[0032] In particular, the cartridge assembly 10 comprises a filter cartridge 100 adapted to perform the filtration of the fluid. The filter cartridge 100 defines a main axis X-X along which it has preferential development.

[0033] The filter cartridge 100 comprises a filter medium 110 that extends around said main axis X-X and defines a central cavity 110'. In other words, the filter medium 110 is of the hollow cylindrical type.

[0034] Preferably, the filter medium 110 is traversable by the fluid according to a radial direction from the inside outwards, i.e. entering cavity 110' and exiting from the peripheral outer walls of the filter medium 110.

[0035] The filter medium 110 comprises a plurality of filter layers 111, 112. Preferably, each layer is adapted to perform a different fluid filtration action; for example, in the solution with diesel fuel, the filter medium 110 is first adapted to filter the solid particles dispersed in the fluid and then it is adapted to divide decouple any water particles from the diesel.

[0036] Among the different filter layers 111, 112 making up the filter medium 110 is a first electrically conductive layer 111. Preferably, the first layer 111 is adapted to be electrically supplied so as to increase the temperature thereof and heat the fluid traversing it, for example in such a way as to allow the dissolution of paraffin crystals in the diesel, or ice crystals or condensation drops present in the air or in the blow-by gases at low temperatures. That is to say, the electric current supplied through the first layer 111 and particularly in the conductive parts thereof is adapted to adjust the temperature itself of the first layer 111 by Joule effect.

[0037] Such a first layer 111 is therefore facing cavity 110'. Preferably, the first layer 111 extends peripherally to cavity 110' surrounding it circumferentially . [0038] According to a preferred embodiment, the first layer 111 is made of an electrically conductive composite polymeric material, preferably non-woven fabric. Preferably, the first layer 111 is of a composite material consisting of non-conductive support fibres (typically synthetic, such as polyester, polyamide) and electrically conductive fibres (such as silver, steel, stainless steel) . Preferably, the first layer 111 is made of a composite material consisting of polyester fibres and silver fibres. Preferably, the first layer 111 is electrically heated through the conductive fibres (e.g. silver) . Preferably, the first layer 111 has the conductive fibres arranged randomly between the support fibres; in other words, the contact between the conductive fibres is such as to allow the electricity to flow in the first layer 111. In yet other words, the first layer 111 has a random three-dimensional cobweb (in the thickness of the first layer 111) of conductive fibres in which electricity flows depending on the electric supply of said first layer 111.

[0039] The present invention is in no way limited by the number or type of additional layers of the filter medium 110.

[0040] According to a preferred embodiment, the filter cartridge 100 comprises a cartridge structure 120 comprising a first plate 121 and a second plate 122 located at the axial ends of the filter medium 110. In other words, the described filter medium 110 is enclosed sandwich-wise between the first plate 121 and the second plate 122. Preferably, in a preferred embodiment in which the filter cartridge 100 operates vertically, the first plate 121 is identified as upper plate, while the second plate 122 is identified as lower plate.

[0041] According to a preferred embodiment, the first plate 121 has an inlet mouth 121' through which the fluid to be filtered flows into cavity 110' of the filter medium 110. Preferably, said inlet mouth 121' has the shape of a collar adapted to be operatively associated with the casing of the filtration assembly described hereinafter.

[0042] Moreover, according to a preferred embodiment, the cartridge structure 120 comprises a central support frame 125 of the first layer 111 facing cavity 110.

[0043] Preferably, the central frame 125 extends between the first plate 121 and the second plate 122 and has a plurality of longitudinal reinforcement elements 125' extending parallel to the main axis X-X delimiting between them a plurality of passage openings 111' through which the fluid flows towards the first layer 111.

[0044] According to a preferred embodiment, the longitudinal reinforcement elements 125' are angularly equally spaced.

[0045] Moreover, in a preferred embodiment, the central frame 125 comprises a plurality of axially spaced annular reinforcement elements 125", wherein the passage openings 111' are delimited by the intersection of the longitudinal reinforcement elements 125' with the annular reinforcement elements 125".

[0046] Preferably, the annular reinforcement elements 125" are axially equally spaced.

[0047] According to a preferred embodiment, the cartridge structure 120 is of a polymeric material, such as nylon, reinforced nylon or other thermosetting and/or thermoplastic polymers processable by moulding.

[0048] The cartridge assembly 10 object of the present invention further comprises at least one separate annular element 150 elastically yielding.

[0049] The annular element 150 is housed into cavity 110' and is adapted to engage the first layer 111 to perform with a radial action of electrical contact therewith.

[0050] That is to say, the annular element 150 is adapted to be housed in cavity 110' to perform a radial action on the first layer 111 so as to electrically interact therewith .

[0051] Specifically, the annular element 150 is elastically yielding, in such a way as to be configurable, inside cavity 110', in a contact configuration in which it performs said radial contact action on the first layer 111.

[0052] In other words, the annular element 150 is elastically radially yielding, in other words it is collapsible towards the centre and is adapted to perform an action outwards.

[0053] Preferably, afterwards (i.e. once inserted in said fixing configuration in cavity 110' ), the annular element 150 is then engageable by an external component of the filtration assembly 1, for example by the candle element 20, to electrically connect with the first layer 111 of the cartridge assembly 10.

[0054] According to a preferred embodiment, the annular element 150 is adapted to contact the first layer 111 through some passage openings 111'. According to a preferred embodiment, the annular element 150 has contact portions specially shaped to fit in the passage openings

111' and contact the first layer 111.

[0055] Preferably, the annular element 150 has a "petal" shape. In other words, the annular element 150 has the shape of an "annular comb".

[0056] According to a preferred embodiment, the annular element 150 is in one piece.

[0057] According to a preferred embodiment, the annular element 150 is obtained starting from a single sheet of paper then specially folded. Preferably, said folding is adapted to impart to the annular element 150 the elastic properties thereof.

[0058] Preferably, the annular element further comprises at least two gripping eyelets 157 adapted to be gripped to perform the above radial collapsing in the insertion operations of the annular element 150 in cavity 110'.

[0059] Preferably, the annular element 150 is of a material adapted to conduct electricity, preferably metal, preferably stainless steel, aluminium, copper or other conductive metal alloys.

[0060] In other words, the annular element 150 if contacted by a special electrode (e.g. placed on the candle element 20 as described hereinafter) is adapted to allow the supply of the first layer 111.

[0061] Preferably, as widely described hereinafter, the annular element 150 comprises an inner edge 152 facing towards the centre, and adapted to be contacted by an electric supply to transmit current to the first layer 111.

[0062] According to a preferred embodiment, the cartridge assembly 10 object of the present invention comprises two axially spaced annular elements 150', 150"; preferably, the two annular elements 150', 150" are placed in proximity to the ends of cavity 110', preferably in proximity to the first plate 121 and the second plate 122.

[0063] Preferably, the two annular elements 150 are adapted to be connected to the electric supply with different polarity .

[0064] According to a preferred embodiment, moreover, the filter cartridge 100 comprises at least one abutment ring 190 placed radially on the opposite side of the first layer 111 with respect to cavity 110' adapted to provide a solid abutment to the radial action of the separate annular element 150. In other words, the abutment ring 190 is adapted to annularly support the radial thrust action of the separate annular element 150.

[0065] According to this embodiment, the radial thrust action of the separate annular element 150 supported by the abutment ring 190 involves a collapsing action of the first layer 111. Advantageously, with the abutment ring 190, the electrical contact between the annular element 150 and the first layer 111 is thus improved and ensured.

[0066] Preferably, the abutment ring 190 is of a plastic material and/or a conductive material; preferably, the abutment ring 190 has radial holes through which the fluid flows.

[0067] According to a preferred embodiment, the abutment ring 190 is placed on the first layer 111, radially outside it, or is placed on the second layer 112, radially inside it.

[0068] According to a preferred embodiment, for each separate annular element 150 there is provided an abutment ring 190, axially arranged on axis X-X to interact with the respective separate annular elements 150; for example, the filter cartridge 100 has two abutment rings 190', 190".

[0069] According to a preferred embodiment, the abutment rings 190 are integrated into a single abutment structure that is placeable on the first layer 111, radially outside it, or on the second layer 112, radially inside it. Preferably, such a structure is shaped as a reticular tubular element comprising a plurality of openings provided for the passage of the fluid.

[0070] Preferably, the abutment rings 190 are arranged axially on axis X-X so as to be substantially radially aligned with the respective annular contact element 150 inserted into cavity 110' of the cartridge assembly and also with the respective electrical contact 201 provided on the candle element 20.

[0071] According to a preferred embodiment, the cartridge assembly 10 is adapted to house a candle element 20 inside cavity 110' which extends by length and is adapted to engage the annular element 150 or the optional two annular elements 150', 150", in such a manner as to be electrically connected with the first layer 111 therethrough .

[0072] According to a preferred embodiment, in the mutual engagement between the candle element 20 and the annular element 150, the annular element 150 is adapted to undergo a radial thrust action in such a way as to increase the radial action on the first layer 111 consolidating the electrical contact. In other words, fitting the cartridge assembly 10 on the candle element 20, the annular element 150 undergoes a radial outward action which in turn is relieved on the first layer 111. That is to say, the electrical contact between the annular element 150 and the first layer 111 is increased.

[0073] According to a preferred embodiment, the mutual engagement between the candle element 20 and the annular element 150 is of the bayonet type. Preferably, in fact, in proximity to the inner edge 152, the annular element 150 has a plurality of slits 152', at the contact portions 151, such as to allow the axial passage of special components of the candle element 20, such as the electrical contacts 201', 201" thereafter adapted, in rotation, to engage the inner edge 152 to radially press it . [0074] According to a preferred embodiment, the annular element 150 in the contact configuration is adapted to perform a fixing action to the first layer 111. That is to say, the radial action that the annular element 150 performs on the filter medium 100 is such as to involve the fixing thereto.

[0075] In this embodiment, therefore, the annular element 150 is also engageable by an external component of the filtration assembly 1, for example by the candle element 20, for the support and fixing of the cartridge assembly 10 to the casing of the filtration assembly 1.

[0076] Preferably, the candle element 20 comprises special fixing teeth 200 extending radially. In the embodiment with two annular elements 150', 150", the candle element 20 comprises two fixing teeth 200 operating therewith.

[0077] In a preferred embodiment, the fixing teeth 200 are adapted to also perform the above electrical contact, in other words, in such an embodiment the fixing teeth 200', 200" correspond with electrical contacts 201', 201".

[0078] In other embodiments, proximal to the fixing teeth 200', 200" are the electrical contacts 201', 201".

[0079] According to a preferred embodiment, the fixing teeth 200 are L-shaped in such a way as to have a radial projection adapted to engage the bottom of the respective annular element 150. With the fixing teeth 200, therefore, the cartridge assembly 10 is axially fixed to the candle element 20 (as shown in figures 5 and 5') · In other words, according to what is shown, the fixing teeth 200 are specially adapted to axially block (or hook, or clamp) the cartridge assembly 10.

[0080] In other embodiments, said axial fixing of the cartridge assembly 10 with the candle element 20 is preferably achieved by providing radial wings within the first plate 121 adapted to mutually engage with the first upper end of the candle element 20, thus fixing it; preferably, said radial wings project inside the inlet mouth 121' and are adapted to operate with the candle element 20 to perform a mutual axial fixing.

[0081] An object of the present invention is also a candle element 20 for a filtration assembly 1 of a fluid. As is clear from the drawings and the description, said candle element 20 is an element that extends in a preferred axial direction, for example, when inserted into the cartridge assembly 10 to be extended along the main axis X-X.

[0082] According with the above description, the candle element 20 is adapted to engage a cartridge assembly 10 in order to implement an electrical contact between the candle element 20 and first conductive layer 111.

[0083] Preferably, the candle element 20 is adapted to engage the annular element 150 of a cartridge assembly 10, or to engage the annular elements 150', 150" of a cartridge assembly 10.

[0084] According to a preferred embodiment, in the engagement between a candle element 20 and cartridge assembly 10, the second one is supported by the first one .

[0085] Preferably, the second plate 122 of the filter cartridge 100 performs an axial abutment for the candle element 20 in its insertion in the axial direction.

[0086] Preferably, moreover, the candle element 20 comprises electric supply means 210 comprising at least one electrical contact 201, or a plurality of electrical contacts 201', 201", adapted to electrically connect to the first layer 111 through the respective annular element 150. In a preferred embodiment, each electrical contact 201', 201" of the candle element 20 is adapted to operate with a respective annular element 150. Preferably, therefore, the candle element 20 in its length has said electrical contacts 201', 201" axially mutually spaced.

[0087] In the accompanying figures, the electric supply lines through which said electrical contact 201 or said electrical contacts 201', 201" is/are electrically connected to a power supply and control unit are not shown; preferably, said power supply and control unit is placed on the housing casing 5.

[0088] According with the foregoing, the candle element 20 is adapted to engage an annular element 150 of a cartridge assembly 10 with a bayonet engagement. As described above, by means of said bayonet contact, the candle element 20 performs a further radial action on the annular element 150 adapted to consolidate the engagement of the annular element 150 to the first layer 111, i.e. the electrical contact and optionally the fixing, if required .

[0089] Moreover, in a preferred embodiment, the fixing teeth 200 are L-shaped in such a way as to have a radial projection adapted to engage the bottom of the respective annular element 150. With the fixing teeth 200, therefore, the cartridge assembly 10 is axially fixed to the candle element 20 (as shown in figures 5 and 5') · In other words, according to what is shown, the fixing teeth 200 are specially adapted to axially block (or hook, or clamp) the cartridge assembly 10.

[0090] According to a preferred embodiment, moreover, the candle element 20 comprises a water detection probe 250, preferably placed at an axial end of the candle element 20, adapted to detect a predefined quantity of filtered water in the filtration assembly 1. [0091] Preferably, said water detection probe 250 protrudes from the lower end of the candle element 20. For example, the water detection probe 250 is placed at a lower end of the candle element 20; preferably, the second plate 122, or lower plate, has a detection hole 122' specially shaped to allow the passage of the water detection probe 250 and thus be adapted to detect a possible quantity of water accumulated in the filtration assembly 1.

[0092] The object of the present invention is also a filtration assembly 1 of a fluid, preferably fuel, preferably diesel, comprising a cartridge assembly 10 having the features described above, and a candle element 20 in turn having the features described above.

[0093] According to a preferred embodiment, the filtration assembly 1 comprises a housing casing 5, preferably comprising two half shells adapted to engage with each other, for example by screwing, defining a filtration chamber 50'; in said filtration chamber 50', fluid filtration is performed; in fact, said filtration chamber 50' is adapted to house the cartridge assembly 10 and the candle element 20.

[0094] According to a preferred embodiment, the candle element 20 is supported integrally with the housing casing 5 and the cartridge assembly 10 is integrally supported by the candle element 20 through the mutual engagement between the annular element 150 and the candle element 20.

[0095] Moreover, the object of the present invention is also a method of producing and assembling a cartridge assembly 10 having the features described above. Such a method comprises the steps of:

producing and assembling the filter media 110, producing the plurality of filter layers 111, 112, identifying cavity 110' , positioning the electrically conductive first layer 111 facing it;

inserting at least one annular element 150 within cavity 110', collapsed in an insertion configuration;

- releasing the annular element 150 in a contact and/or fixing configuration in it which performs a radial action on the first layer 111 so as to create an electrical contact and possibly involve the fixing thereof to the first layer 111.

[0096] Preferably, the production and assembly step of the filter medium 100 also comprises a step in which at least one abutment element 190 is placed along axis X-X between the first layer 111 and the second layer 112. In this way, in the insertion step of the at least one annular element 150, this is placed at such an axial height that the annular element 150 and the abutment element 190 are radially aligned. [0097] In addition, the object of the invention is also the method of producing and assembling a fluid filtration assembly, which comprises the steps of:

- assembling a cartridge assembly 10 according to the above description;

- fitting the cartridge assembly 10 on a candle element 20, preferably with a bayonet coupling, creating an electrical contact between candle element 20 and first layer 111 of the cartridge assembly.

[0098] In the present description, reference is always made to an annular element 150; annular element 150 defines a component which in some preferred embodiments, extends in its entirety circumferentially at 360°, but also a component which in some preferred embodiments, like that widely shown in the accompanying figures, has at least one radial slit, like that widely shown in the accompanying figures, has a radial slit at the sides whereof are the gripping eyelets 157.

[0099] Innovatively, the cartridge assembly, the candle element and the filtration assembly described above amply meet the object of the present invention overcoming the typical drawbacks of the prior art.

[00100] Advantageously, in fact, the cartridge assembly ensures an efficient and effective electrical contact to the first electrically conductive layer using a separate component from the filter cartridge, that is, the annular element. Advantageously, therefore, it is not necessary to design and provide specific embodiments of the filter cartridge. In other words, in fact, unlike the prior art solutions, in which special electrical contacts are provided and/or housed on the cartridge structure, the solution object of the present invention leaves that technical function to the annular element. Advantageously, the adjustment of the temperature of the first layer of the filter medium, using electric current, is efficient and effective to be implemented.

[00101] Moreover, advantageously, the solution object of the present invention allows greater design freedom to the designer.

[00102] A further advantageous aspect lies in the possibility of having a first layer of a conductive polymeric composite materials, which due to the action of the annular element is effectively electrically contacted in such a way as to ensure the electric supply of the random three-dimensional cobweb of conductive fibres.

[00103] An even further advantageous aspect lies in the fact that due to the bayonet engagement with the candle element, the annular element is adapted to increase its radial action on the first layer, thus improving the contact action thereof. [00104] Advantageously, the annular element is adapted to also perform the fixing to the filter medium; advantageously, the cartridge structure is not necessary for the performance of this features, it being performed by the annular elements and by their interaction with the candle element.

[00105] Moreover, advantageously, all the necessary electronics to bring the supply to the first layer is housable on the candle element, and optionally partially on the housing casing. Advantageously, also the candle element is provided with the water detection probe. In other words, advantageously, the filter cartridge does not have a complex shape, i.e. complicated by the presence of special electronic components and/or water detection probes as it occurs in the prior art embodiments .

[00106] Advantageously, the production and assembly of the cartridge assembly and of the filtration assembly are extremely simplified: firstly, the design and production of the filter cartridge exhibits no problems related to the presence of electronic components; secondly, the assembly operations are immediate and intuitive.

[00107] It is clear that a man skilled in the art may make changes to the cartridge assembly, to the candle element and to the filter assembly in order to meet incidental needs, all falling within the scope of protection defined in the following claims.

List of reference numerals:

1 filter assemb1y

5 housing casing

50' filtration chamber

10 cartridge assembly

X-X main axis

100 filter cartridge

110 filter medium

110' cavity

111 first layer

111' passage openings

112 second layer

120 cartridge structure

121 first plate or upper plate

121' inlet mouth

122 second plate or lower plate

122' detection hole

125 central frame

125' longitudinal reinforcement elements

125" annular reinforcement elements

150 annular element

151 contact portions

152 inner portion 152' slits

157 gripping eyelets

150' first annular element 150" second annular element 190 abutment ring

190' first abutment ring

190" second abutment ring 20 candle element

200 fixing teeth

200' first fixing tooth

200' second fixing tooth

210 electric supply means

201 electrical contact

201' first electrical contact 201" second electrical contact 250 water detection probe

Claims

1. A cartridge assembly (10) for a filtration assembly of a fluid (1), preferably fuel, preferably diesel, comprising a candle element (20) extending in length comprising electric supply means (210) provided with at least one electrical contact (201) , wherein the cartridge assembly (10) comprises:

i) a filter cartridge (100) having a main axis (X-X) , comprising :

- a filter medium (110) that extends around said main axis (X-X), and defines a central cavity (110') adapted to accommodate said candle element (20), wherein the filter medium (110) is traversable by the fluid from the inside outwards and comprises a plurality of filter layers (111, 112) including a first layer (111), electrically conductive, facing the cavity (110'), for controlling the temperature thereof so as to heat the fluid traversing it;

- a cartridge structure (120) comprising a first plate (121) and a second plate (122) placed at the axial ends of the filter medium (110) ;

ii) at least one separate annular element (150), electrically conductive, wherein said separate annular element (150) is elastically yielding, housed in the cavity (110') in a contact configuration in which it performs a radial contact action on the first layer (111) identifying an electrical contact between the annular element and the first layer (111) ;

where in said separate annular element (150) is electrically engageable by said candle element (20) through the electric supply means (210) and in particular by the at least one electrical contact (201) .

2. A cartridge assembly (10) according to claim 1, comprising two annular elements (150', 150"), axially spaced, preferably placed in proximity of the ends of the cavity (110'), preferably in proximity of the first plate (121) and the second plate (122) .

3. A cartridge assembly (10) according to any of the preceding claims, wherein the annular element (150) is made in a single piece in a material suitable to conduct electric current, preferably in metal, preferably in stainless steel.

4. A cartridge assembly (10) according to any of the preceding claims, wherein the cartridge structure (120) comprises a central support frame (125) of the first layer (111) facing the cavity (110') that extends between the first plate (121) and the second plate (122), wherein the central frame (125) has a plurality of longitudinal reinforcement elements (125') that extend parallel to the main axis (X-X) delimiting between them a plurality of passage openings (111') through which the fluid flows, wherein the annular element (150) contacts the first layer (111) through a number of passage openings (111') .

5. A cartridge assembly (10) according to claim 4, wherein the central frame (125) further comprises a plurality of axially spaced annular reinforcement elements (125"), wherein the passage openings (111') are delimited by the intersection of the longitudinal reinforcement elements (125') with the annular reinforcement elements (125") .

6. A cartridge assembly (10) according to claim 4 or 5, wherein the longitudinal reinforcement elements (125') are mutually angularly equidistant and/or the annular reinforcement elements (125") are mutually axially equidistant, wherein the annular element (150) has contact portions (151) specially shaped to be inserted into the passage openings (111') and to contact the first layer (111) .

7. A cartridge assembly (10) according to any of the preceding claims, in which the annular element (150) is collapsible in an insertion configuration in which it is insertable into the cavity (110') and is suitable to be released inside it in the fixing configuration so as to perform said radial action on the first layer (111) .

8. A cartridge assembly (10) according to any of the preceding claims, wherein the first layer (111) is made of an electrically conductive composite polymeric material, preferably non-woven fabric.

9. A cartridge assembly (10) according to any of the preceding claims, in wherein the filter cartridge (100) further comprises at least one abutment ring (190), for example two abutment rings (190, 190"), placed radially on the opposite side of the first layer (111) with respect to the cavity (100') adapted to provide a solid abutment to the radial action of the separate annular element ( 150 ) .

10. A cartridge assembly (10) according to any of the preceding claims, wherein the annular element (150', 150") comprises an inner portion (152) engageable by the candle element (20) in such a way that in the mutual engagement between the candle element (20) and the annular element (150), the annular element (150) is adapted to undergo a radial thrust action such as to increase the radial action on the first layer (111) thereby consolidating the mutual electrical contact.

11. A cartridge assembly (10) according to claim 10, wherein the mutual engagement between the candle element (20) and the annular element (150) is of the bayonet type .

12. A candle element (20) for a filtration assembly of a fluid (1) comprising electric supply means (210), wherein the candle element (20) is suitable to engage a cartridge assembly (10) according to any of the preceding claims interacting with the annular element (150), wherein the candle element (20) comprises at least one electrical contact (201) suitable to electrically connect to the first layer (111) through the annular element (150) .

13. A candle element (20) for a filtration assembly of a fluid (1) according to claim 12 in conjunction with claim 2, wherein the electric supply means (210) comprise, placed on the candle element (20), two electrical contacts (201', 201") adapted to operatively engage with and electrically connect to a respective annular element (150' , 150") .

14. A candle element (20) according to claim 13, wherein said engagement with the annular element (150) of the cartridge assembly (10) is of the bayonet type.

15. A candle element (20) according to any of claims 12 to 14, comprising a water detection probe (250), preferably at an axial end of the candle element (20), suitable to detect a predefined quantity of filtered water in the filtration assembly (1) .

16. Filtration assembly of a fluid (1), preferably fuel, preferably diesel, comprising:

i) a cartridge assembly (10) according to any one of claims 1 to 11;

ii) a candle element (20) according to any of claims 12 to 15.

17. Filtration assembly of a fluid (1) according to claim 16, comprising:

iii) a housing casing (5) identifying a filtration chamber (50'), suitable to house the cartridge assembly (10) and the candle element (20)

wherein the candle element (20) is integrally supported by the housing casing (5) ;

wherein the cartridge assembly (10) is supported integrally by the candle element (20) through the mutual engagement between the annular element (150) and candle element (20) .

18. Method of producing and assembling a cartridge assembly (10), for the inner outer radial filtration, according to any of claims 1 to 11, comprising the steps of:

producing and assembling the filter medium (110), producing the plurality of filter layers (111, 112), identifying the cavity (110') and positioning the electrically conductive first layer (111) facing it;

- inserting at least an annular element (150), inside the cavity (110'), collapsed in an insertion configuration, released in a contact configuration in which it performs a radial action on the first layer (111) in such a way to create an electrical contact.

19. Method of producing and assembling a cartridge assembly (10) according to claim 17 in conjunction with claim 9, wherein the production and assembly step of the filter medium (100) further comprises a step in which at least one abutment element (190) is placed along the axis (X-X) between the first layer (111) and the second layer (112), wherein in the insertion step of the at least one annular element (150), this is placed at an axial height such that the annular element (150) and the abutment element (190) are radially aligned.

20. Method of producing and assembling a filtration assembly (1) of a fluid, preferably fuel, preferably diesel, according to claims 16 and 17, comprising the steps of:

- assembling a cartridge assembly (10) according to claim 18;

- fitting the cartridge assembly (10) on a candle element (20) according to any of claims 12 and 15, creating an electrical contact between candle element (20) and first layer (111) of the cartridge assembly (10) .