Housing of air filter for IC engines and air filter incorporating said housing

Abstract

 A housing (11) of air filter for internal combustion engines, comprising: a container (13) having a holding recess (15) for the filtering element (17); a cover (31), removably housed in said holding recess (15) and containing said filtering element (17); a duct (19) for the air to be filtered and a duct (23) for the cleaned air, communicating with said holding recess; wherein said cover (31) has side walls (31a, 31b) defining a sealing edge (34) for a fluid-tight gasket (17a) for said filtering element and an abutment edge (36) projecting radially outwards from said side walls for the mechanical fastening of the cover (31) into the holding recess (15); wherein said sealing edge (34) and said abutment edge (36) are non-coplanar.

Description

Technical field

[0001] The present invention relates to a housing of air filter for internal combustion engines, and to an air filter incorporating said housing.

Prior art

[0002] As known, internal combustion engines, in particular vehicle engines, need a filter for cleaning air sucked from the outside environment and directed to the combustion chambers.

[0003] In many cases, the air filter consists of a cartridge of filtering material, housed within a sealed housing, mainly equipped with air inlet and outlet ports and with a holding recess for the cartridge. Inside the housing, there is defined a path compelling the inflowing air to pass through the cartridge before flowing out through the outlet port. The cartridge may be made for instance of pleated paper and be of different shapes and sizes.

[0004] EP 1 433 947 discloses an air filter for IC engines including a housing, a cartridge equipped with a fluid-tight gasket, and air inlet and outlet ports. The cartridge is housed within the housing in a seat closed by a removable cover, which is secured to the housing by means of screws arranged along a cover edge cooperating with a corresponding edge of the housing in order to sandwich the cartridge gasket therebetween, to ensure the required fluid seal between the cartridge and the housing.

[0005] EP 1 593 834 discloses another example of a housing for an air filter, which can be located in the upper part of the engine compartment. A seat for the filtering element communicating with air inlet and outlet ducts is provided and the housing includes a cover secured by means of screws along an abutment edge retaining the gasket for the cartridge.

[0006] FR 2 922 269 discloses a further example of a housing for an air filter for IC engines, including a container equipped with a cover and a side opening for the introduction of the filtering cartridge, which is surrounded by a frame equipped with a gasket. The frame and the gasket are sandwiched between the container and the cover when the housing is closed.

[0007] As known, the housings of air filters are to be designed so as to meet two requirements that not always are compatible: on the one side, the housing is to internally define an air flow path such that air flows through the cartridge, which in turn is to be sized so as to meet the needs of the engine the filter is associated with, and on the other side the housing is to fit to the conformation of the engine and the other devices associated therewith, and in particular to the available room in the engine compartment.

[0008] The latter requirement is particularly felt in the automotive field, where component size reduction, while possibly improving the efficiency and the reliability of the same components, is a strongly felt need.

[0009] The prior art devices are not sufficiently compact to meet the modern requirements of size reduction, and thus it is a main object of the present invention to provide a housing of air filter for internal combustion engines, which has a reduced size while maintaining a considerable filtering capacity.

[0010] It is a further object of the invention to provide a housing of the above kind, which is cheap and easy to be manufactured so that it can be industrially produced on a large scale.

Description of the invention

[0011] The above and other objects are achieved by the housing and the filter according to the invention, as defined in the appended claims.

[0012] According to a first advantageous aspect of the invention, the fluid seal between the gasket surrounding the filtering element and the mechanical fastening between the cover and the container of the housing take place in non-coplanar areas. More particularly, according to the invention, the fluid seal and the abutment between the cover and the container of the housing are defined in different planes, preferably in substantially parallel planes. Thanks to this feature, it is advantageously possible to reduce the housing thickness so that it is very close to the thickness of the filtering element only.

[0013] Advantageously, still in accordance with the invention, thanks to the arrangement of the air ducts that extend along the walls of the holding recess for the cartridge, also the longitudinal and transversal sizes of the housing are considerably reduced. Notwithstanding this, the filter generally maintains a high filtering capacity, determined by the wide surface for passage of air towards the holding recess in which the cartridge is held and from the holding recess towards the outlet duct.

[0014] The housing of air filter for internal combustion engines according to the invention is thus extremely thin and compact and it can be located also in engine compartments of small cars, for instance runabouts, in particular between the engine and the bonnet.

[0015] Another advantage of the invention is the possibility of making the housing by using a reduced number of components.

[0016] A further, but not the last, advantage of the invention is that the housing made in this manner is aesthetically appealing tanks to the provision of a substantially flat top shell, of which the shape and the size can moreover be defined at will, for instance in order to hide engine components.

Brief Description of the Figures

[0017] A preferred embodiment of the invention is disclosed by way of non-limiting example with reference to the accompanying drawings, in which:

• Fig. 1 is a top perspective view of the housing according to the invention;
• Figs. 2A and 2B are top and bottom exploded views, respectively, of the filter according to the invention;
• Fig. 3 is a bottom perspective view of the housing shown in Fig. 1;
• Fig. 4 is a bottom plan view of the housing shown in Fig. 1;
• Figs. 5 and 6 are cross sectional views taken along lines V - V and VI - VI, respectively, of Fig. 4.

Description of a Preferred Embodiment

[0018] Referring to Fig. 1, the housing of air filter for internal combustion engines according to the invention has been generally denoted by reference numeral 11 and is shown from above, i.e. substantially as it would appear when opening the bonnet of a vehicle into which the filter is incorporated according to a standard arrangement.

[0019] Turning to Figs. 2A, 2B and 3, housing 11 includes a container 13 where a holding recess 15 housing a removable cover 31 is defined.

[0020] A duct 19 for the dirty air, equipped with an aperture 21 for the entrance of air to be filtered, and a duct 23 for the cleaned air, equipped with an aperture 25 for the exit of the filtered air, are further defined in container 13

[0021] Container 13 further includes an upper base 27, substantially made as a shell in the illustrated example, which further preferably defines a corresponding upper portion of the walls of ducts 19 and 23. Said base 27 moreover closes upwards one of the bases of holding recess 15 and preferably it is permanently associated with container 13, for instance by welding or gluing, when housing 11 is being made.

[0022] Holding recess 15 is further equipped in its lower portion, i.e. on the side opposite upper base 27, with an aperture 29 through which removable cover 31 can be introduced into holding recess 15, until closing said aperture 29.

[0023] According to the invention, holding recess 15 has a substantially prismatic shape, preferably a parallelepiped shape with two parallel opposite short walls 15a and two parallel opposite long walls 15b.

[0024] Introduction of cover 31 into holding recess 15 takes place according to an approach direction substantially parallel to said side walls 15a, 15b of holding recess 15 and, in the illustrated embodiment, substantially perpendicular to the portion of upper base 27 closing holding recess 15 upwards.

[0025] Dirty air duct 19 communicates with holding recess 15 through an aperture 20 provided along one of the side walls of said holding recess 15. In the illustrated example, aperture 20 is located on one of the long side walls 15b of holding recess 15.

[0026] Clean air duct 23 communicates with holding recess 15 through a passageway 24 defined between base 27 and the side walls of holding recess 15. In the illustrated example, said passageway 24 substantially extends between base 27 and two adjacent side walls 15a, 15b.

[0027] Cover 31 internally houses a filtering element 17, which may include a prism-shaped or, in the illustrated example, parallelepiped-shaped cartridge. In an exemplary embodiment, the cartridge may be obtained by means of a corresponding panel of pleated paper or other material with appropriate separation properties. The cartridge will be further provided with a peripheral sealing gasket 17a, preferably integrated and made of plastic material, for instance a polyurethane foam. Said gasket 17a extends around the panel defining filtering element 17 and projects radially outwards from the side walls of said filtering element 17.

[0028] Cover 31 includes a body with complementary shape to holding recess 15, thus substantially parallelepiped-shaped in the illustrated example, with a base 30 and two parallel opposite short walls 31a and two parallel opposite long walls 31b. Walls 31a, 31b surround a holding recess 32, parallelepiped-shaped in the illustrated example, housing filtering element 17.

[0029] An aperture 22 is provided on the wall of cover 31 facing air inlet aperture 20 when cover 31 is housed in holding recess 15. In the illustrated example, said aperture 22 is provided on one of long walls 31b.

[0030] Said walls 31a, 31b are further provided with a peripheral edge 36 projecting radially outwards from walls 31a, 31b, and preferably extending without interruptions around the whole cover 31. Said edge 36 forms a corresponding abutment for cover 31, allowing the mechanical fastening of cover 31 into holding recess 15. Cover 31 may be fastened to container 13 by means of fastening means, such as for instance screws 33 passing through holes provided in abutment edge 36 and intended to engage container 13. By removing screws 33, cover 31 can therefore be removed from holding recess 15, to allow replacing filtering element 17 located inside cover 31.

[0031] Removal of cover 31 from holding recess 15 takes place according to a removal direction substantially parallel to said side walls 15a, 15b of holding recess 15 and, in the illustrated embodiment, substantially perpendicular to the portion of upper base 27 closing holding recess 15 upwards.

[0032] According to the invention, the depth of holding recess 32 is chosen so that filtering element 17 can be received in recess 32 by leaving the portion surrounded by peripheral gasket 17a outside, and said gasket will abut against the axially sealing free edge 34 of side walls 31a, 31b of cover 31.

[0033] Correspondingly, the depth of holding recess 15 defined in container 13 is chosen so that, when cover 31 is introduced into holding recess 15 and edge 36 abuts against the corresponding abutment edge 18 of walls 15a, 15b of holding recess 15, gasket 17a is in contact with a peripheral sealing edge 16 projecting into holding recess 15 and extending on a plane spaced apart from base 27 in order to define passageway 24 between said sealing edge 16 and base 27. It is evident that sealing edge 16 and edge 34, being to define the fluid seal with gasket 17a, preferably extend each on a respective single plane and without interruptions.

[0034] In such a manner, by closing cover 31 by means of screws 33, the flattening of gasket 17a between sealing edge 34 and sealing edge 16 and the consequent fluid seal are determined, thereby ensuring that dirty air entering holding recess 15 through aperture 20 passes through filtering element 17 before being exhausted through passageway 24. On the contrary, the closure between sealing edge 36 and sealing edge 18 needs not to be a fluid-tight one, since air possibly entering between both edges is directed towards the region where air to be filtered is present.

[0035] From the above description it will be appreciated that, according to the invention, the fluid seal between gasket 17a surrounding filtering element 17 and the mechanical fastening between cover 31 and container 13 take place in separate areas, more precisely non-coplanar areas. More particularly, according to the invention, the fluid seal and the abutment between cover 31 and container 13 are defined on different planes. The plane on which the mechanical fastening between cover 31 and holding recess 15 occurs is indeed separate from the plane on which fluid seal is determined thanks to gasket 17a. Actually, according to the invention, abutment edge 36 for fastening screws 33 lies on a plane other than that on which gasket 17a extends. Said planes are spaced apart by a distance of the order of the thickness of cover 31, and consequently of the order of the thickness of filtering element 17, typically a few centimetres, for instance in the range 3 to 10 cm.

[0036] As it can be better seen in Fig. 4, clean air duct 23 extends over at least part of two adjacent walls of holding recess 15, which in the illustrated example are a short wall 15a and a long wall 15b of said holding recess 15 and, correspondingly, of cover 31, and are parallel to transversal axis "T" and longitudinal axis "L", respectively. More precisely, always referring to the illustrated example, a first section 23a of duct 23 extends along short wall 15a of holding recess 15 and a second section 23b extends along the adjacent long wall 15b. Moreover, ducts 19, 23 will preferably have a wall portion in common with walls 15a, 15b.

[0037] Moreover, according to the invention, dirty air duct 19, besides extending over at least part of one of the walls (long wall 15b in the illustrated example), also has a corresponding section 19a extending along base 30 of said cover 31.

[0038] Similarly, clean air duct 23, besides extending along at least part of two adjacent walls of holding recess 15, as said above, also extends along that portion of base 27 defining the base of said holding recess 15, thereby defining passageway 24 for clean air outflow.

[0039] Thanks to a such an arrangement of ducts 19 and 23 relative to holding recess 15 for filtering element 17, air flowing though filtering element 17 housed in holding recess 15 can reach clean air duct 23 through a large surface, with considerable advantages for the overall filtering capacity of the filter, and yet housing 11 is kept extremely compact in particular in respect of its thickness, i.e. in the direction of vertical axis "V" (Fig. 5).

[0040] Always in accordance with the invention, dirty air inlet duct 21 preferably extends along part of the same long wall 15b of holding recess 15 along which section 23b of clean air outlet duct 23 extends.

[0041] Advantageously, thanks to such an arrangement, the housing according to the invention is extremely compact in the direction of both longitudinal axis "L" and transversal axis "T",

[0042] Referring to Figs. 5 and 6, filtering element 17 is substantially laterally surrounded by walls 31a, 31b of cover 31.

[0043] Moreover, the thickness of region 14 occupied by filtering element 17 in holding recess 32 in cover 31, which cover is in turn housed in holding recess 15, and consequently the thickness of filtering element 17, i.e. its extension in the vertical direction of axis "V", is lower than the overall thickness of holding recess 15.

[0044] Said region 14 is positioned in cover 31 at an intermediate location, always with reference to the vertical direction of axis "V", so that, when cover 31 is housed in holding recess 15, in said holding recess 15 there are defined a first portion with thickness "d1" (lower portion in Fig. 5), associated with aperture 20 of dirty air duct 19, a second portion with thickness "d2" (upper portion in Fig. 5), associated with clean air passageway 24 and a third portion, or intermediate region 14, with thickness "d3", in which filtering element 17 is arranged.

[0045] According to the invention, housing 11 cab be advantageously made by assembling a reduced number of components, each obtained by moulding plastic materials.

[0046] In the illustrated example, housing 11 is substantially made of three parts, namely a single container, integrating air inlet and outlet ducts 19, 23 and walls 15a, 15b of holding recess 15, shell-shaped upper base 27 and cover 31. The single container integrating air inlet and outlet ducts 19, 23 and walls 15a, 15b of holding recess 15 is preferably permanently joined with base 27 by welding or gluing, whereas cover 31 is removably joined with the walls of holding recess 15. Moreover, said three parts possibly have associated therewith fittings mainly intended to contribute to noise reduction, to allow associating the housing with the air circuit and to allow fastening the housing to the engine.

[0047] Even if the invention has been disclosed with reference to a presently preferred particular embodiment, all obvious changes and modifications that will be apparent to the skilled in the art are included within the scope of the invention.

Claims

1. Housing (11) of air filter for internal combustion engines, comprising:

- a container (13), where a holding recess (15) for a filtering element (17) is defined;

- a cover (31), removably housed in said holding recess (15) and in turn arranged to house said filtering element (17);

- a duct (19) for the dirty air, communicating with said holding recess (15) through an aperture (20) and equipped with an inlet aperture (21) for the air to be filtered;

- a duct (23) for the cleaned air, communicating with said holding recess (15) through a passageway (24) and equipped with an outlet aperture (25) for the filtered air;

- wherein said holding recess (15) is of a substantially prismatic shape and the duct (23) for the cleaned air extends over at least part of two adjacent walls (15a, 15b) of said holding recess (15);

- wherein said cover (31) has side walls (31a, 31b) surrounding a holding recess (32) for the filtering element, said side walls defining a sealing edge (34) for a fluid-tight gasket (17a) for said filtering element;

- wherein said cover (31) has a peripheral edge (36) projecting radially outwards from said side walls and defining an abutment edge for said cover (31), allowing the mechanical fastening of the cover (31) into the holding recess (15);

- wherein said sealing edge (34) for the fluid-tight gasket (17a) and said abutment edge (36) for said cover are non coplanar.

2. Housing according to claim 1, wherein said sealing edge (34) for the fluid-tight gasket (17a) and said abutment edge (36) for said cover (31) extend on respective, substantially parallel planes.

3. Housing according to claim 2, wherein said sealing edge (34) for the fluid-tight gasket (17a) and said abutment edge (36) for said cover (31) extend on planes spaced apart by a distance substantially equal to the thickness of the cover (31).

4. Housing according to claim 1 or 2 or 3, wherein the container (13) of the housing further includes an upper base (27) defining a corresponding upper portion of the walls of the air ducts (19, 23), and wherein said base (27) closes one of the bases of the holding recess (15) for the filtering element (17), said holding recess (15) being further equipped, on the side opposite said upper base (27), with an aperture (29) through which the removable cover (31) can be introduced into the holding recess (15), until closing said aperture (29).

5. Housing according to claim 4, wherein the holding recess (15) has a substantially parallelepiped shape, and wherein the introduction of the cover (31) into the holding recess (15) takes place according to an approach direction substantially parallel to said side walls (15a, 15b) of the holding recess (15) and substantially perpendicular to the portion of the upper base (27) closing the holding recess (15).

6. Housing according to any preceding claim, wherein the holding recess (15) has two parallel opposite short walls (15a) and two parallel opposite long walls (15b).

7. Housing according to any preceding claim, wherein the cover (31) includes a body with complementary shape to the holding recess (15) and having a base (30) and side walls (31a, 31b), and wherein the side walls (31a, 31b) surround said holding recess (32) for the filtering element (17).

8. Housing according to claims 6 and 7, wherein said cover (31) includes a substantially parallelepiped-shaped body, with two parallel opposite short walls (31a) and two parallel opposite long walls (31b).

9. Housing according to any preceding claim, wherein the cover (31) is fastened to the container (13) by means of screws (33) passing through holes provided in the peripheral edge (36) projecting radially outwards from said side walls and defining an abutment edge for said cover (31), said screws being intended to engage the container (13).

10. Housing according to any preceding claim, wherein the depth of said holding recess (32) in the cover (31) is chosen so that the filtering element (17) can be received in said holding recess (32) by leaving the portion surrounded by peripheral gasket (17a) outside.

11. Housing according to claim 10, wherein the depth of the holding recess (15) defined in the container (13) for said cover (31) is chosen so that, when the cover (31) is introduced into the holding recess (15), the fluid-tight gasket (17a) is in contact with a peripheral sealing edge (16) projecting into the holding recess (15), so that, by closing the cover (31) by the screws (33), the flattening of the gasket (17a) between the sealing edge (34) of the cover and the sealing edge (16) of the holding recess, and the consequent fluid seal, are determined, thereby ensuring that dirty air entering the holding recess (15) passes through the filtering element (17) before being exhausted.

12. Housing according to claim 11, wherein said peripheral sealing edge (16) projecting into the holding recess (15) extends on a plane spaced apart from the base (27) in order to define the air outlet passageway (24).

13. Housing according to any preceding claim, wherein said cover has, on its side wall, an aperture (22) facing the air inlet aperture (20) when the cover (31) is housed in the holding recess (15).

14. Housing according to any preceding claim, wherein the dirty air inlet duct (19) preferably extends over part of the same wall of the holding recess (15) over which a section of the clean air outlet duct (23) extends.

15. Air filter for internal combustion engines, including a housing (11) according to any of claims 1 to 14, in which there is housed a filtering element (17) including a panel of a material with appropriate separation properties provided with a peripheral sealing gasket (17a) surrounding the filtering element (17) and projecting radially outwards from the side walls of said panel.

Drawing