WO2019082034A1

WO2019082034A1 - Filtration assembly of an aqueous fluid

Info

Publication number: WO2019082034A1
Application number: PCT/IB2018/058150
Authority: WO
Inventors: Giorgio Girondi
Original assignee: UFI Innovation Center SRL
Current assignee: UFI Innovation Center SRL
Priority date: 2017-10-23
Filing date: 2018-10-19
Publication date: 2019-05-02
Anticipated expiration: 2020-04-23
Also published as: IT201700119893A1; EP3700653A1; WO2019082072A1

Abstract

The invention is a filtration assembly of an aqueous fluid (1) of an injection system of said aqueous fluid. The filtration assembly (1) operates in a working configuration in which the aqueous fluid is filtered and flows towards the injector and in a backflow configuration in which a flow of air and/or water flows in the opposite direction towards the tank. The filtration assembly (1) extends along a main axis (X- X) and comprises: - a housing body (2); - a filter cartridge (3) housed in the housing body (2) identifying in the housing body (2) a raw side (X) and a clean side (Y); - a control head (5) which closes tightly the housing body (2) fluidically connected to the raw side (X) and to the clean side (Y) wherein the control head (5) controls the flow direction of the aqueous fluid and/or the flow of water and/or air passing through the assembly (1) comprising at least a pair of non-return valves (50).

Description

DESCRIPTION

"FILTRATION ASSEMBLY OF AN AQUEOUS FLUID "

Field of application

[0001] The present invention relates to a filtration assembly of an aqueous fluid of an injection system of said fluid. The present invention also relates to a water supply system to the combustion chamber of the engine of a vehicle comprising said filtration assembly. In addition, the present invention relates to a urea supply system to the catalyst of a vehicle.

[0002] The present invention lies in the automotive sector and has its specific application in systems that comprise an injector suitable to atomize the aqueous fluid filtered by a filtration assembly. In other words, the specific filtration assembly of the present invention is placed in the vehicle in the vicinity of said injector: the filtration assembly of the present invention is therefore extremely compact in size.

[0003] In particular, aqueous fluid is understood to refer to water or even to urea.

[0004] The filtration assembly of the present invention is therefore suitable to filter such aqueous fluid from suspended material and unwanted particles in such a way that the possibility of them reaching the injector or injectors is avoided. [0005] In addition, the filtration assembly is also suitable to perform backflow operations in which it is emptied of the quantity of aqueous fluid inside it. Such backflow operations are also known as "purging operations " .

[0006] In the state of the art filtration assemblies are known of suitable to perform filtering operations and suitable to be subjected to backflow operations.

[0007] The main problem encountered in such filtration assemblies is that of not being able to efficiently perform both the filtering operations and the backflow operations, with particular reference to the latter.

Solution according to the invention

[0008] The need is therefore strongly felt to provide a specific filtration assembly for the filtration of an aqueous fluid of an injection system of said fluid which performs the filtering operations in an efficient manner, but at the same time is also able to perform in an equally efficient manner the backflow operations, maximizing the expulsion of the fluid from therein.

[0009] At the same time the need is also strongly felt to have a filtration assembly which has compact dimensions, but above all which allows simple and intuitive maintenance operations to be performed.

[0010] The purpose of the present invention is therefore to provide a filtration assembly which is suitable to operate in a working configuration in which it performs the filtration of the aqueous fluid and a backflow configuration in which performs the elimination of the aqueous fluid from inside it. Such purpose of the present invention must also fulfil the need to have a filtration assembly with a simple geometry suitable to allow simple and intuitive maintenance operations, such as the replacement of the filter cartridge included therein.

[0011] Such purpose is achieved by the filtration assembly according to claim 1. Such purpose is also achieved by a water supply system to the combustion chamber of the engine of a vehicle according to claim 21 and by a urea supply system to the catalyst of a vehicle according to claim 22.

[0012] The dependent claims show preferred embodiment variants having further advantageous aspects.

Description of the drawings

[0013] 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:

- Figures la and lb show a first schematic cross-section of a filtration assembly according to the present invention respectively in a working configuration and in a backflow configuration suitable to be placed in the vehicle and to operate in a horizontal position;

- Figures 2a and 2b illustrate a second schematic cross- section of a filtration assembly according to the present invention respectively in a working configuration and in a backflow configuration suitable to be placed in the vehicle and to operate in a horizontal position;

- Figures 3a and 3b illustrate a third schematic cross- section of a filtration assembly according to the present invention respectively in a working configuration and in a backflow configuration suitable to be placed in the vehicle and to operate in a vertical position;

- Figures 4a and 4b show a fourth schematic cross-section of a filtration assembly according to the present invention respectively in a working configuration and in a backflow configuration suitable to be placed n the vehicle and to operate in a vertical position;

- Figures 5a and 5b illustrate a fifth schematic cross- section of a filtration assembly according to the present invention respectively in a working configuration and in a backflow configuration suitable to be placed in the vehicle and to operate in a horizontal position;

- Figures 6a and 6b illustrate a sixth schematic cross- section of a filtration assembly according to the present invention respectively in a working configuration and in a backflow configuration suitable to be placed in the vehicle and to operate in a horizontal position;

Figures 7a and 7b show a seventh schematic cross- section of a filtration assembly according to the present invention respectively in a working configuration and in a backflow configuration suitable to be placed in the vehicle and to operate in a horizontal position;

- Figures 8a and 8b illustrate an eighth schematic cross- section of a filtration assembly according to the present invention respectively in a working configuration and in a backflow configuration suitable to be placed in the vehicle and to operate in a horizontal position;

- Figures 9a and 9b illustrate a ninth schematic cross- section of a filtration assembly according to the present invention respectively in a working configuration and in a backflow configuration suitable to be placed in the vehicle and to operate in a vertical position;

Figures 10 and 10' show a perspective view and a perspective view in separate parts of a filtration assembly according to the present invention respectively in a first embodiment;

- Figures 10a, 10a' and 10a" represent a side view and two views in longitudinal cross-section along the sectional plane V-V of Figure 10a and VI-VI of Figure 10a' ;

- Figures 10b and 10b' illustrate a bottom view and a view in longitudinal cross-section along the sectional plane VII-VII of Figure 10b;

- Figures 11 and 11' show a perspective view and a perspective view in separate parts of a filtration assembly according to the present invention respectively in a second embodiment;

- figures 11a and 11a' represent a side view and a view in longitudinal cross-section along the sectional plane

VIII-VIII of Figure 11a;

- Figures lib and lib' illustrate a bottom view and a view in longitudinal cross-section along the sectional plane IX-IX of Figure lib;

- Figures 11c and 11c' illustrate a view from above and a view in longitudinal cross-section along the sectional plane X-X of Figure lie;

Figures 12 and 12' show a perspective view and a perspective view in separate parts of a filtration assembly according to the present invention respectively in a third embodiment;

- Figures 12a, 12a', 12a", 12a' ' ' represent one view from above and three views in longitudinal cross-section respectively along the sectional planes XI-XI, XII-XII, XIII-XIII of Figure 12a; - Figures 12b and 12b' illustrate a bottom view and a view in longitudinal cross-section along the sectional plane XIV-XIV of Figure 12b;

- Figures 13a and 13b represent two perspective views of a filter cartridge and a control head according to one embodiment ;

Figures 14 and 14' show a perspective view and a perspective view in separate parts of a filtration assembly according to the present invention respectively in a further embodiment;

Detailed description

[0014] In the appended drawings, reference numeral 1 globally denotes a filtration assembly of an aqueous fluid according to the present invention, in a preferred embodiment .

[0015] The filtration assembly 1 finds its specific application in an injection system of said aqueous fluid.

[0016] In particular, such injection system comprises a tank positioned fluidically upstream of the assembly suitable to contain the fluid and an injector positioned fluidically downstream of the assembly and suitable to receive the filtered fluid from the assembly to atomize it.

[0017] According to the present invention such a system also comprises at least one pump unit suitable to move the fluid inside the system.

[0018] The present invention also relates to a water supply system to the combustion chamber of the engine of a vehicle comprising a pump unit suitable to perform a circulation action on the water, a water tank, a filtration assembly 1 according to the description, and at least one injector suitable to atomize the water to supply it to the combustion chamber of the engine group.

[0019] The present invention also relates to a system for supplying urea to the catalyst of a vehicle comprising a pump unit suitable to perform a circulation action on the urea, a urea tank, a filtration assembly 1 according to the description, and at least one injector suitable to atomize the urea.

[0020] The filtration assembly 1 of the present invention extends mainly in a longitudinal direction. The filtration assembly 1 extends in fact along a main axis X-X.

[0021] As already mentioned, and as evident in its application in injection systems, the filtration assembly 1 of the present invention has compact dimensions. Preferably, in fact, the filtration assembly 1 has an axial dimension A with respect to the main axis X-X between 100 mm and 130 mm. Preferably, in fact, the filtration assembly 1 has a diametrical dimension D with respect to the main axis X-X between 40 mm and 60 mm.

[0022] The filtration assembly of an aqueous fluid 1 is then fluidly connected to the various components of the injection system presenting, upstream of the assembly 1, a tank, while, downstream, at least one injector.

[0023] The filtration assembly 1 operates in two configurations: in a working configuration in which the aqueous fluid is filtered and flows towards the injector and in a backflow configuration in which a flow of air and/or water flows in the opposite direction i.e. towards the tank.

[0024] The filtration assembly 1 comprises a housing body 2 suitable to define a housing inside which the fluid flows .

[0025] The housing body 2 has a substantially longitudinal extension along the main axis X-X.

[0026] According to a preferred embodiment, the housing body 2 is made of metal, preferably aluminium.

[0027] The housing body 2 comprises side walls 22 substantially parallel to the main axis X-X.

[0028] The housing body 2 at one axial end of the side walls 22 comprises an inlet aperture 21. The housing body 2 at the other axial end of the side walls 22 comprises a bottom wall 23. According to one embodiment, in the working configuration, the aqueous fluid enters the housing body 2 through the inlet aperture 21.

[0029] According to one embodiment, in the working configuration, the aqueous fluid flows out of the housing body 2 through the inlet aperture 21.

[0030] According to an alternative embodiment, in the working configuration, the aqueous fluid flows out of the housing body 2 through an outlet mouth 230 comprised in the bottom wall 23. Preferably, said outlet mouth 230 has the shape of a nozzle and extends in length in the axial direction. In a preferred embodiment, said nozzle is positioned in correspondence with the main axis X-X. In other embodiment variations the nozzle is positioned offset from the main axis X-X.

[0031] According to other further embodiments, an outlet mouth is made on the side wall 22.

[0032] According to a preferred embodiment, the housing body 2, and in particular the side walls 22, have a cylindrical shape.

[0033] According to a preferred embodiment, the filtration assembly 1 also comprises a thermally insulating layer 8 housed inside the housing body 2, preferably on the side walls 22. Preferably, thanks to this thermally insulating layer 8 direct contact between the aqueous fluid and the walls of the housing body 2 is avoided and/or minimized so as to thermally insulate the volume inside it. [0034] Preferably, said thermally insulating layer 8 is in an elastomeric material, preferably a closed cell foam. According to this embodiment, said thermally insulating layer 8 is also suitable to provide a compensation volume making it possible to compensate any volume changes inside the housing body 2 i.e. due to the formation of ice inside it.

[0035] The filtration assembly 1 further comprises a filter cartridge 3 suitable in the working configuration to filter the aqueous fluid from suspended particles and impurities in such a manner that they do not reach the at least one injector provided in the system.

[0036] Said filter cartridge 3 is housed in the housing body 2.

[0037] According to a preferred embodiment, the filter cartridge 3 identifies in the housing body 2 a raw side X and a clean side Y. In the working configuration on the raw side X the fluid to be filtered flows and as a result the suspended particles and impurities are accumulated, while on the clean side Y filtered fluid flows, therefore not containing suspended particles and impurities.

[0038] According to a preferred embodiment, the filter cartridge 3 comprises a head plate 31, a bottom plate 32 and, between the two, a filter medium 30.

[0039] According to a preferred embodiment, the filter medium 30 is of the cylindrical tubular type defining a central cavity 300.

[0040] Preferably the filter medium 30 is a synthetic material of non-woven fabric composed of synthetic fibres, preferably made of polypropylene. According to a preferred embodiment, the filter medium 30 is configured in the shape of a cylinder or folded in the shape of a star .

[0041] According to a preferred embodiment, the filter medium 30 is traversable by the fluid radially.

[0042] According to a preferred embodiment, in the working configuration, the filter medium 30 is traversable by the fluid from the outside to the inside: the raw side X is outside the filter medium 30, the clean side Y in the central cavity 300.

[0043] According to a preferred embodiment, the head plate 31 comprises a head mouth 310 fluidically connected to the head 5 as described and shown in the appended drawings and/or to the outlet mouth 230.

[0044] According to a preferred embodiment, the bottom plate 32 comprises a bottom mouth 320 fluidically connected to the head 5 as described and shown in the appended drawings and/or to the outlet mouth 230.

[0045] The filtration assembly 1 comprises, in fact, a control head 5 which controls the flow direction of aqueous fluid and/or flow of water and/or air which traverses the assembly 1. In other words, it is thanks to the control head 5 that the filtration assembly 1 operates in a working configuration and in a backflow configuration.

[0046] According to a preferred embodiment, the control 5 head is fluidically associated with the raw side X and with the clean side Y of the housing body 2.

[0047] According to a preferred embodiment, the head 5 closes tight the inlet aperture 21. Preferably, the head 5 engages the side walls 22 closing tight the inlet aperture 21.

[0048] In the working configuration, the entrance of the aqueous fluid to be filtered in the housing body 2 is through the head 5. In the backflow configuration, the output of the flow of water and/or air from the housing body 2 is through the head 5.

[0049] According to a preferred embodiment, the head 5 is at least partially housed in the housing body 2.

[0050] According to a preferred embodiment, the head 5 comprises a sealing collar 55 suitable to be housed in the housing body 2. Preferably, said sealing collar 55 houses one or more sealing gaskets 555 suitable to engage the housing body 2.

[0051] According to a preferred embodiment, the head 5 and the filter cartridge 3 are reciprocally engaged to each other. Preferably, the head 5 and the filter cartridge 3 are fluidically connected to each other. Preferably, the head 5 is fluidically connected through the head mouth 310 to the clean side Y inside the central cavity 300 of the filter cartridge 300.

[0052] According to a preferred embodiment, the filter cartridge 3 is directly engaged to the head 5. Preferably, the head plate 31 is suitable to engage the head 5.

[0053] According to a preferred embodiment, the filtration assembly 1 comprises engagement members 7 which are coupleable geometrically to each other in such a way as to ensure the mutual engagement between the filter cartridge 3 and the head 5 in a unique angular position with respect to the main axis X-X.

[0054] Preferably the engagement members 7 comprise (as shown in figures 13a and 13b) protruding elements and recessed elements specially shaped to couple in reciprocal axial insertion operations between the cartridge 3 and head 5. For example, the head plate 31 of the cartridge 3 comprises at least one axial protuberance 73 and the head 5 comprises at least one axial groove 75 shaped to house the at least one axial protuberance 73. Preferably, the position and/or the shape of the aforesaid engagement members 7 allows a unique mutual angular position between the cartridge filter 3 and the head 5. Preferably thanks to the aforesaid engagement members 7 the mutual engagement and disengagement operations between the head 5 and cartridge 3 are simplified

[0055] According to a preferred embodiment, the filtration assembly comprises locking means 9 suitable to reciprocally engage the head 5 and the housing body 2 to ensure their mutual integral locking unaffected by pressures of the flow of water and/or air flow.

[0056] In a preferred embodiment (shown for example in figures 10, 11 and 12), said locking means 9 comprise a clip element 90 suitable to be inserted into slots specifically made on the housing body 2 and head 5 blocking any axial movement thereof. Preferably, said clip element 90 is U-shaped and has two arms suitable to be inserted in special slots facing distal with respect to the main axis X-X present on the housing body 2 and head 5.

[0057] According to a further preferred embodiment (shown for example in figure 14), said locking means 9 comprise at least one locking screw 99 (preferably four angularly spaced) ; wherein the head 5 and housing body 2 are specially shaped to have dedicated slots for housing said locking screws 99.

[0058] According to a preferred embodiment, the control head 5 comprises at least one pair of non-return valves 50: a first non-return valve 51 and a second non-return valve 52. In particular special fluidic ducts are provided in the head 5 suitable to allow the flow of aqueous fluid to be filtered and water and/or air in the backflow operations.

[0059] In the working configuration, the first non-return valve 51 is open and the second non-return valve 52 is closed .

[0060] Vice versa in the backflow configuration, the second non-return valve 52 is open and the first non-return valve 51 is closed.

[0061] In other words, the first non-return valve 51 and the second non-return valve 52 operate in opposite directions .

[0062] According to a preferred embodiment, in the backflow configuration, the flow of water and/or air flows into the housing body 2 passing through the clean side Y, bypassing therefore the filter medium 30 and the raw side X.

[0063] According to a preferred embodiment, the first non^¬ return valve 51 is fluidically connected to the raw side X. [0064] According to a preferred embodiment, the second non^¬ return valve 52 is fluidically connected to the clean side Y.

[0065] According to a preferred embodiment, the control head 5 comprises two pairs of non-return valves 50; 50' .

[0066] Each pair of non-return valves 50; 50' comprises a first non-return valve 51; 51' and a second non-return valve 52 ; 52 ' .

[0067] In the working configuration, the first non-return valves 51, 51' are open while the second non-return valves 52, 52' are closed.

[0068] Vice versa in the backflow configuration, the second non-return valves 52, 52' are open while the first nonreturn valves 51, 51', are closed.

[0069] According to said embodiment with two pairs of non^¬ return valves 50, 50' these are fluidically arranged in such a manner that by means of their respective actuation the direction of the flow in the working configuration and in the backflow configuration provides that the flow of water and/or air passes first through the raw side X and then through the clean side Y. In other words, even the backflow configuration provides for a filtering of the flow of water and/or air.

[0070] According to a preferred embodiment, the filtration assembly 1 comprises an uptake unit 4 fluidically connected with the head 5.

[0071] According to a preferred embodiment, the uptake unit 4 is fluidically connected to the housing body 2 and in particular to the outlet mouth 230.

[0072] According to a preferred embodiment, the uptake unit 4 is fluidically connected with the at least one pair of non-return valves 50, 50' suitable to extend in length between the head 5 and the bottom wall 23.

[0073] According to a preferred embodiment, the uptake unit 4 is housed in the central cavity 300 of the filter medium 30.

[0074] According to a preferred embodiment, the uptake unit 4 comprises a first uptake cannula 41 fluidly connected to the second non-return valve 52.

[0075] Preferably, the first uptake cannula extends inside the central cavity 300 of the filter medium 30.

[0076] Preferably, the first uptake cannula 41 extends in length from the head 5 comprising a first uptake mouth 410 positioned proximally to the bottom wall 23.

[0077] According to a preferred embodiment, the first uptake cannula 41 is integrally connected to the head 5.

[0078] According to a further preferred embodiment, the first uptake cannula 41 is integrally connected with the filter cartridge 3.

[0079] Said first uptake cannula 41 is preferably connected to the second non-return valve 52 in such a way that in the backflow configuration the flow of water and/or air reaches the second non-return valve 52 after crossing the first uptake cannula 41 entering them in the first uptake mouth 410.

[0080] According to a preferred embodiment, in addition, the uptake unit 4 further comprises a second uptake cannula 42 fluidically connected with the output mouth 230.

[0081] Preferably, the second uptake cannula 42 extends from the bottom wall 23 in length comprising a second uptake mouth 420 positioned proximally to the head 5.

[0082] Preferably, the second uptake cannula extends inside the central cavity 300 of the filter medium 30.

[0083] According to a preferred embodiment, the second uptake cannula 42 is integrally connected with the bottom wall 23.

[0084] According to a further preferred embodiment, the second uptake cannula 42 is integrally connected with the filter cartridge 3.

[0085] Said second uptake cannula 42 is preferably connected to the bottom mouth 320. Said second uptake cannula 42 comes out inside the central cavity 300 of the filter medium 30 and communicates fluidically with the second non-return valve 52 in such a way that in the backflow configuration the flow of water and/or air reaches the housing body 2 after crossing the second uptake cannula 42 coming out of it through the second uptake mouth 420; subsequently the flow of water and/or air passes through the first uptake mouth 410 and the first uptake cannula 41 reaching the second non-return valve from which the water/air flow returns to the tank.

[0086] According to a preferred embodiment, the filtration assembly 1, further comprises a heating unit 6 operatively connected to the head 5 to perform on the head 5, on the filter cartridge 3 (preferably on the filter medium 30) and/or on the aqueous fluid in the housing body 2 a heating action.

[0087] Preferably, the heating unit 6 is suitable to regulate the temperature of the housing body 2, preferably increasing it, to dissolve any ice present or prevent the formation of ice inside it. In fact the ice adversely affects the work of the filtration assembly 1 since the ice crystals obstruct the filter medium 30. At the same time, the ice will adversely affect the operation of the filtration assembly 1 since the ice crystals prevent the correct operation of the non-return valves .

[0088] Preferably, said heating unit 6 is electrically connectable to electrical power supply means in the vehicle .

[0089] According to a preferred embodiment, the heating unit 6 comprises a heating device 60 which extends in length axially in the housing body 2.

[0090] According to a preferred embodiment, the heating device 60 has a rod-like shape and is positioned parallel to the axis (X-X) housed inside the central cavity 300.

[0091] Preferably, the heating device 60 comprises a candle or pen heater with PTC resistor.

[0092] Preferably, the heating device 60 is positioned in such a way as to lie on the axis X-X.

[0093] According to a preferred embodiment (shown by way of example in figure 10a' ) , the heating device 60 extends inside the central cavity 300 but is positioned externally with respect to both the first uptake cannula 41 and the second uptake cannula 42. According to this solution, a better heating capacity is achieved and heaters of different shapes with finned geometries are integrable to increase the heat exchange efficiency.

[0094] According to a preferred embodiment, as shown by way of example in Figure 11c, the heating device 60 extends inside the central cavity 300 and is positioned inside the first uptake cannula 41. This solution makes it possible to optimize the use of space and use the cannula to create a heat shield effect of the filter material, preventing it from overheating.

[0095] According to a preferred embodiment, the heating device 60 comprises an electrically conductive metallic element so as to electrically power it to increase the temperature thereof.

[0096] According to a preferred embodiment, and above all according to the description above, the filtration assembly 1 is suitable to be placed in the vehicle in a substantially vertical position, i.e. in a position in which the main axis X-X is substantially perpendicular to the plane on which the vehicle moves. According to the description above, the filtration assembly 1 is suitable to perform the filtration and backflow operations in an extremely effective manner, even when placed in a vertical position.

[0097] Innovatively, the filtration assembly of an aqueous fluid fully absolves the purpose of the present invention overcoming the drawbacks typical of the prior art. Innovatively, the drawbacks typical of the prior art are resolved even in a water supply system to the combustion chamber of the engine of a vehicle and also in a urea supply system to a catalyst of a vehicle comprising said filtration assembly.

[0098] Advantageously in fact the filtration assembly operates in an extremely effective manner both performing filtrations operations and backflow operations.

[0099] Advantageously, the filtration assembly has a simple uncomplicated geometry thanks to which simple maintenance operations are performable. In particular it is possible to leave the control head in situ (on the vehicle) while the housing body and the filter cartridge is removable from it, the latter being of simple construction, free of complex components and replaceable in a simple and intuitive manner when needed.

[00100] Advantageously, the filtration assembly is suitable to operate effectively even when placed in a vertical position in the vehicle.

[00101] Advantageously, the filtration assembly comprises an uptake unit suitable to maximize the amount of water drained depending on the specific orientation of the main axis of the filtration assembly.

[00102] In addition, advantageously, thanks to the positioning of the uptake mouth of the cannula fluidically connected to the second non-return valve in a position proximal to the bottom wall, it is possible to delay reaching the "gurgling" condition in which the amount of drained water is practically nil. Advantageously, this uptake cannula makes it possible to maximize the "draining" capacity of the filtration assembly, maximizing the amount of water discharged into the tank. Advantageously, thanks to this uptake cannula the thermal power associated with the heater is reduced and so is the possibility of damaging the heater and/or filter and/or head.

[00103] Advantageously, thanks to the uptake unit the amount of residual water trapped in the filtration assembly is minimized greatly reducing the risks associated with the formation of ice.

[00104] Advantageously the presence of the second uptake cannula also maximizes the amount of water drained, forcing the column of water collected in the inner cavity of the filter medium to come out of the filtration assembly through the other cannula connected to the head.

[00105] Advantageously, the greater the axial distance between the second uptake mouth and the first uptake mouth the greater the amount of water discharged from the central cavity of the filter.

[00106] Advantageously, the filtration assembly comprises engagement members suitable to assist the technician performing maintenance operations to find the respective angular position between head and cartridge

[00107] In addition, advantageously, by means of said projecting or recessed engagement members, it is easier to remove the cartridge from the control head, facilitating the transmission of forces necessary to disengage the two components, minimizing the transmission of these stresses to the body of the heater which is particularly sensitive.

[00108] Advantageously, the filtration assembly comprises engagement members provided on the cartridge suitable to ensure the positioning of the uptake unit, in particular of the cannula connected to the second non^¬ return valve, in the lowest position possible in horizontal applications.

[00109] Advantageously, the filtration assembly comprises locking means suitable to lock the head and housing body in such a way that even at high pressures (up to 30 bar) these components remain firmly connected and in place. Advantageously also said locking means are easy to manoeuvre in such a way as to allow easy maintenance .

[00110] Advantageously the filtration assembly comprises a heating unit which regulates the temperature of the filtration assembly, increasing the temperature in case of need, such as when for example the ambient temperature the vehicle is moving in is very low (close to 0 degrees centigrade or below 0 degrees centigrade) .

[00111] Advantageously, the filtration assembly is compact in size in order to be housed in the vehicle and in the small spaces present therein, especially with reference to the engine unit.

[00112] Advantageously, the filtration assembly is designable and producible (as shown in the appended drawings 10 to 14) in such a way that all the components envisaged and described fit in the small space provided. Advantageously, the uptake unit and heating unit are housable inside the filter cartridge. Advantageously the non-return valves are positionable in the head so as to allow the housing of the heating unit.

[00113] Advantageously, as shown in the appended drawings 1 to 9 various geometric solutions of the filtration assembly are envisaged all widely involving the advantages described above.

[00114] It is clear that a person skilled in the art may make modifications to the filtration assembly or supply systems comprising it so as to satisfy contingent requirements, all contained within the scope of protection as defined by the following claims.

List of reference numbers:

1 filtration assembly of an aqueous fluid

2 housing body

21 inlet aperture

22 side walls

23 bottom wall 230 outlet mouth

3 filter cartridge

30 filter medium

300 central cavity

31 head plate

310 head mouth

32 bottom plate

320 bottom mouth

4 uptake unit

41 first uptake cannula

410 first uptake mouth

42 second uptake cannula

420 second uptake mouth

5 control head

50 pair of non-return valves

50' second pair of non-return valves

51, 51' first non-return valve

52, 52' second non-return valve 55 sealing collar

555 sealing gasket

6 heating unit

60 heating device

7 engagement members

73 axial protuberance

75 axial groove 8 thermally insulating layer

9 locking means

90 clip element

99 locking screw

X-X main axis

A axial dimension

D diametral dimension

X raw side

Y clean side

Claims

1. A filtration assembly of an aqueous fluid (1), of an injection system of said aqueous fluid comprising upstream of the assembly (1) a tank and downstream of the assembly (1) at least one injector, wherein the filtration assembly (1) operates in a work configuration in which the aqueous fluid is filtered and flows towards the injector and in a backflow configuration in which a flow of air and/or water flows in the opposite direction towards the tank, in which the filtration assembly (1) extends along a main axis (X-X) and comprises:

- a housing body (2) having side walls (22) substantially parallel to the main axis (X-X) bounded at their respective ends by a bottom wall (23) and an inlet aperture (21) ;

- a filter cartridge (3) housed in the housing body (2), wherein said filter cartridge (3) comprises a head plate (31), a bottom plate (32) and, between the two, a filter media (30) of the cylindrical tubular type defining a central cavity (300), wherein the filter cartridge (3) identifies in the housing body (2) a raw side (X) and a clean side (Y) ;

a control head (5) which closes tightly the inlet aperture (21) and is fluidically connected to the raw side (X) and to the clean side (Y) of the housing body (2), wherein the control head (5) controls the flow direction of the aqueous fluid flow and/or the flow of water and/or air passing through the assembly (1) comprising at least a pair of non-return valves (50) wherein, in the working configuration, a first non-return valve (51) is open and a second non-return valve (52) is closed and vice versa in the backflow configuration.

2. A filtration assembly (1) according to claim 1, wherein, in the backflow configuration, the flow of water and/or air flows into the housing body (2) passing through the clean side (Y) , bypassing the filter media (30) and the raw side (X) .

3. A filtration assembly (1) according to claim 1, wherein the control head (5) comprises two pairs of non- return valves (50; 50' ), each comprising a first nonreturn valve (51; 51') and a second non-return valve (52; 52'), fluidically arranged in such a manner that by means of their respective actuation the direction of the flow in the working configuration and in the backflow configuration provides that the flow of aqueous fluid and/or the flow of water and/or the flow of the air passes first through the raw side (X) and then through the clean side (Y) .

4. A filtration assembly (1) according to any of the preceding claims, wherein, in the working configuration, the filter media (30) is crossed by the flow of water in a radial direction from the outside to the inside.

5. A filtration assembly (1) according to any of the preceding claims, wherein the bottom wall (23) comprises an outlet mouth (230) through which, in the working configuration, filtered aqueous fluid flows.

6. A filtration assembly (1) according to any of the preceding claims, wherein the head plate (31) comprises a head mouth (310) connected with the head (5) and/or the bottom plate (32) comprises a bottom mouth (320) fluidly connected with the head (5) and/or with the outlet mouth (230) .

7. A filtration assembly (1) according to any of the preceding claims, further comprising an uptake unit (4) fluidically connected with the at least one pair of non^¬ return valves (50, 50') suitable to extend in length between the head (5) and the bottom wall (23) .

8. A filtration assembly (1) according to claim 7, wherein the uptake unit (4) is housed in the central cavity (300) .

9. A filtration assembly (1) according to claim 7 or claim 8, wherein the uptake unit (4) comprises a first uptake cannula (41) fluidly connected to the second non^¬ return valve (52), wherein the first uptake cannula (41) extends in length from the head (5) comprising a first uptake mouth (410) positioned proximally to the bottom wall (23) .

10. A filtration assembly (1) according to claim 9, wherein said first uptake cannula (41) is integrally connected to the head (5) or is integrally connected with the filter cartridge (3) .

11. A filtration assembly (1) according to claim 5 and any one of claims from 9 to 10, wherein the uptake unit (4) further comprises a second uptake cannula (42) fluidically connected with the output mouth (230), wherein the second uptake cannula (42) extends from the bottom wall (23) in length comprising a second uptake mouth (420) positioned proximally to the head (5) .

12. A filtration assembly (1) according to claim 11, wherein said second uptake cannula (42) is integrally connected with the bottom wall (23) or is integrally connected with the filter cartridge (30) .

13. A filtration assembly (1) according to any of the preceding claims, further comprising a heating unit (6) operatively connected to the head (5) to perform on the head (5) and/or on the aqueous fluid and on the filter cartridge (3) in the housing body (2) a heating action, for example suitable to melt ice possibly present.

14. A filtration assembly (1) according to claim 13, wherein the heating unit (6) comprises a heating device (60) which extends in length axially in the housing body (2) .

15. A filtration assembly (1) according to claim 14, wherein the heating device (60) has rod-like shape and is positioned parallel to the axis (X-X) housed inside the central cavity (300) .

16. A filtration assembly (1) according to any of the preceding claims, in which the head (5) and the filter cartridge (3) are mutually engaged comprising engagement members (7) which are coupleable geometrically to each other in such a way as to ensure the mutual engagement in a unique angular position with respect to the main axis (X-X) .

17. A filtration assembly (1) according to any of the preceding claims, in which the head (5) is at least partially housed in the housing body (2), for example comprising a sealing collar (55) suitable for housing in the housing body (2) .

18. A filtration assembly (1) according to claim 17, comprising locking means (9) suitable to reciprocally engage the head (5) and the housing body (2) to ensure their mutual integral locking unaffected by pressures of the flow of water and/or air.

19. A filtration assembly (1) according to any of the preceding claims, wherein the filtration assembly (1) has a compact size having an axial dimension (A) with respect to the main axis (X-X) between 100 mm and 130 mm and a diametric dimension (D) with respect to the main axis (X- X) between 40 mm and 60 mm.

20. A filtration assembly (1) according to any of the preceding claims, wherein the filtration assembly (1) is suitable to be placed in the vehicle in a substantially vertical position, i.e. in a position in which the main axis (X-X) is substantially perpendicular to the plane on which the vehicle moves.

21. System for supplying water to the combustion chamber of the engine of a vehicle comprising a pump unit suitable to perform a circulation action on the water, a water tank, a filtration assembly (1) according to any of the claims from 1 to 20, and at least one injector.

22. System for supplying urea to the catalyst of a vehicle comprising a pump unit suitable to perform a circulation action on the urea, a urea tank, a filtration assembly (1) according to any of the claims from 1 to 20, and at least one injector.