Air duct made of two half-shells
The air duct design with half-shells and protuberances addresses the weight and sealing issues of traditional ducts, providing lightweight, easily assembled, and robust conduits with integrated features.
Patent Information
- Application Number
- FR2023007357
- Authority / Receiving Office
- FR · FR
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2023-07-10
- Publication Date
- 2025-10-24
- Estimated Expiration
- 2043-07-10
AI Technical Summary
Existing air ducts in vehicles are heavy due to their manufacturing process, which results in high energy consumption, and their interface regions are not robust enough to ensure proper sealing and assembly, particularly when the ducts have complex shapes.
The air duct is composed of two half-shells with flat contact surfaces and protuberances that ensure sealing through contact, eliminating the need for complementary fitting, and includes fixing lugs and reinforcing ribs for robust assembly and integration of additional features.
The solution reduces the weight of the ducts, ensures effective sealing, simplifies assembly, and allows integration of additional components, while maintaining structural integrity and resistance to fluid pressure.
Smart Images
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Abstract
Description
Title of the invention: Air duct made of two half-shells
[0001] The present invention relates to an air duct, of the type comprising a first half-shell and a second half-shell together forming a closed-section duct suitable for the circulation of a fluid, said duct extending along a main axis, the first half-shell comprising at least a first interface region and the second half-shell comprising at least a second interface region, the first and second interface regions projecting in a radial direction, substantially perpendicular to the main axis, towards the outside of the duct, the or each first interface region extending opposite the or each second interface region in a contact direction. In the automotive field, air ducts are arranged inside a vehicle to form part, for example, of a system for regulating the temperature inside the passenger compartment of the vehicle.
[0002] These conduits are generally tubular and due to their manufacturing process, are generally heavy.
[0003] However, the heavier a vehicle is, the more energy it tends to consume.
[0004] In order to reduce the weight of vehicles, and in particular of conduits, a first solution is to reduce the thickness of the conduit walls.
[0005] For this purpose, it is known to assemble two half-shells forming a sealed conduit between them. The half-shells are for example formed by injection molding, as opposed to the blow molding usually used to manufacture hollow bodies.
[0006] This manufacturing process makes it possible on the one hand to reduce the thickness of the walls of the half-shells and thus to reduce the weight of the conduit, and on the other hand to form conduits of complex shape.
[0007] In order to form a sealed conduit, each half-shell has at least one interface region intended to be assembled with an interface region of the other half-shell.
[0008] The known interface regions have, for example, complementary shapes intended to fit into one another in order to keep the two half-shells assembled into one another and guarantee the sealing of the conduit.
[0009] However, the interface regions of current half-shells are not sufficiently robust to meet the mechanical requirements of the conduits.
[0010] Furthermore, the interface regions as they exist do not facilitate the assembly of the two half-shells in order to form the conduit.
[0011] Indeed, existing solutions lack, for example, guiding means facilitating the assembly of the two half-shells intended to form a sealed conduit, in particular when the conduit has a complex shape.
[0012] Consequently, if the assembly is poorly made and / or if the interface regions are not robust enough, air leaks out of the duct may occur.
[0013] One of the aims of the invention is to propose an air duct, for example manufactured by an injection process instead of a blowing process, making it possible in particular to reduce the weight of the duct, while ensuring the sealing of the duct and facilitating its assembly.
[0014] To this end, the invention relates to an air duct of the aforementioned type, in which the or each first interface region is formed by a flat contact surface, the second half-shell comprising at least one protuberance projecting from the or each second interface region, said protuberance being applied to a part of the flat contact surface in order to ensure the sealing of the duct by contact between the protuberance and the flat contact surface.
[0015] Since the sealing of the conduit is ensured by the contact between the projecting protuberance of the or each second interface region with the flat contact surface, there is no need to fit the first half-shell with the second half-shell by cooperation of complementary shapes.
[0016] The user therefore does not have to search for the interface regions of each half-shell and make them coincide in order to correctly fit the half-shells and ensure the sealing of the conduit. Thus, even when the conduit has a complex shape, in particular when it extends along a non-rectilinear axis, the assembly of the conduit remains simple.
[0017] By simple contact between the contact surface and the protuberance, the passage of air out of the duct is prevented.
[0018] The assembly of the half-shells is then made easier.
[0019] Furthermore, when the conduit is produced by an injection process, it is possible to integrate other characteristics into the conduit (such as an electronic component interface, the addition of acoustic foam, etc.). The integration of such characteristics into the conduit would be difficult to envisage with a blow-molding manufacturing process.
[0020] According to other advantageous aspects of the invention, the air duct comprises one or more of the following characteristics, taken individually or in all technically possible combinations:
[0021] - the second half-shell comprises two protrusions projecting from the or each second interface region, said protuberances being applied to a part of the flat contact surface of the first half-shell, in order to ensure the sealing of the conduit by contact between the protuberances and the flat contact surface, the protuberances being spaced from each other in the radial direction;
[0022] - the first and second half-shells have a thickness, outside the first and second interface regions, taken parallel to the radial direction, greater than 0.5 mm and / or the first and second half-shells have a thickness, at the level of the first and / or second interface regions, taken parallel to the radial direction, greater than or equal to 0.5 mm;
[0023] - the first and second half-shells each comprise two regions interface extending in projection in the radial direction towards the outside of the conduit, said interface regions extending on either side of the conduit;
[0024] - at least the second interface region comprises at least one attachment zone comprising a fixing lug extending projecting from the second interface region in the contact direction, the fixing lug extending between a first end linked to the fixing zone and a free end, opposite the first end in a longitudinal direction substantially perpendicular to the radial direction, the fixing lug being fixed to the first interface region;
[0025] - an opening for the passage of the fixing lug is provided in the or each part of the first interface region opposite the or each attachment zone of the second half-shell, the attachment tab passing through said opening to be attached to the first interface region;
[0026] - the or each part of the first interface region opposite the or each zone for fixing the second half-shell comprises a projecting element cooperating with the fixing lug in order to reversibly fix the first half-shell on the second half-shell;
[0027] - the or each fixing zone comprises a window extending at least opposite from the free end of the fixing lug;
[0028] - the or each part of the first interface region opposite the or each zone fixing the second half-shell has a U- or L-shaped section, in a plane perpendicular to the main axis;
[0029] - the first half-shell comprises at least one reinforcing rib extending between the duct wall and the first interface region and / or the second half-shell comprises at least one reinforcing rib extending between the duct wall and the second interface region.;
[0030] The invention will appear more clearly on reading the description which follows, given solely by way of non-limiting example, and made with reference to the drawings in which:
[0031] [Fig-1] [Fig.l] is a schematic representation, in section along a plane transverse perpendicular to a main axis of the conduit, of a conduit according to the invention formed of two half-shells assembled in a contact direction;
[0032] [Fig.2] [Fig.2] is a schematic representation in section along a transverse plane of an interface region of the conduit of [Fig.l];
[0033] [Fig.3] [Fig.3] is a perspective view of a conduit attachment region of the [Fig.l];
[0034] [Fig.4] [Fig.4] is a perspective view of a fixing area of a half-shell of the conduit of [Fig.l];
[0035] [Fig.5] [Fig.5] is a perspective view of a portion of the interface region of the other half-shell of the conduit of [Fig.l];
[0036] [Fig.6] [Fig.6] is a sectional view along a transverse plane, of the region of fixing of [Fig.3]; and
[0037] [Fig.7] [Fig.7] is a sectional view along a plane perpendicular to the direction of contact of the attachment region of [Fig.3].
[0038] With reference to [Fig.l], a conduit 1 is described for the circulation of a fluid, more particularly for the circulation of air.
[0039] For example, the conduit 1 may be used in a passenger transport vehicle, for example to form part of a system for regulating the temperature inside the passenger compartment of the vehicle.
[0040] It is understood that such a conduit may be intended for the circulation of any fluid other than air.
[0041] The conduit 1 generally has a cylindrical shape with a closed contour, for example the conduit 1 has a circular, ovoid, polygonal or other section.
[0042] The conduit 1 extends along a main axis, noted P, shown in figures 3, 4, 5 and 7.
[0043] More precisely, the conduit 1 extends along the main axis P, between an inlet, through which the fluid enters the conduit 1 and at least one outlet, through which the fluid leaves the conduit 1.
[0044] In the example shown, the conduit 1 extends along a substantially straight main axis P.
[0045] Alternatively, the main axis P of the conduit is curved.
[0046] According to one embodiment, the main axis P comprises changes of direction so as to comprise components in three dimensions.
[0047] For example, the conduit 1 is an angled conduit, having a section, in a plane containing the main axis P, in the shape of an L, a U, an S or even a Z.
[0048] In all that follows, the terms "transverse" and "transverse" designate an axis, or plane, perpendicular to the main axis P, and the term "radial" designates an axis perpendicular to the main axis P and intersecting a central main axis, noted O in [Fig.l].
[0049] With reference to [Fig.l], the conduit 1 is formed by the assembly of a first half-shell 5 and a second half-shell 10. The first half-shell 5 and the second half-shell 10 have, when assembled, a closed section around the main axis P.
[0050] Figures 1 to 3, 6 and 7 show the first and second half-shells 5, 10 in an assembled position, forming the conduit 1.
[0051] Figures 4 and 5 show the half-shells 5, 10 individually, in a disassembled position.
[0052] The first and second half-shells 5, 10 each extend along the main axis P.
[0053] When the conduit 1 has a rounded outline, the first and second half-shells 5, 10 each have a wall 6, 7 extending, respectively, between a first peripheral edge 5A, 10A and a second peripheral edge 5B, 10B, as shown in [Fig.l].
[0054] The wall 6 of the first half-shell 5 extends from the peripheral edge 5A to the peripheral edge 5B, between an internal face 6A and an external face 6B, opposite the internal face 6A in a radial direction.
[0055] The wall 7 of the second half-shell 10 extends from the peripheral edge 10A to the peripheral edge 10B, between an internal face 7A and an external face 7B, opposite the internal face 7A in a radial direction.
[0056] The internal walls 6A, 7A together form an internal wall of the conduit 1, intended to come into contact with a fluid circulating in the conduit 1.
[0057] The external walls 6B, 7B together form an external wall of the conduit 1.
[0058] For example, the walls 6, 7 have a semi-circular, semi-polygonal section. or even semi-ovoidal.
[0059] It is understood that the first half-shell 5 has a geometry compatible with the second half-shell 10 in order to form the conduit 1 with a closed section.
[0060] By “compatible geometry” is meant that the walls of the half-shells 5, 10 define between them a closed volume outside the inlets and outlets of the conduit 1.
[0061] In particular, the shape and dimensions of the first half-shell 5 are adapted to those of the second half-shell 10 to form the conduit 1 with a closed section.
[0062] The first and second half-shells 5, 10 are for example manufactured by injection molding.
[0063] The first and second half-shells 5, 10 are for example made of a thermoplastic material, for example polypropylene or polyamide.
[0064] In one embodiment, the first half-shell 5 and the second half-shell 10 are made of the same material. Alternatively, the first and second half-shells may be made of two separate materials.
[0065] The first half-shell 5 comprises at least one first interface region 15.
[0066] Similarly, the second half-shell 10 comprises at least a second interface region 20.
[0067] The first and second interface regions 15, 20 extend, for example, in a protruding manner. in a radial direction R, towards the outside of the conduit 1.
[0068] Each interface region 15, 20 extends over the entire length of a peripheral edge 5A, 5B, 10A, 10B of the first and second half-shells 5, 10, taken along the main axis P.
[0069] Each interface region 15, 20 extends in an interface plane defined by the radial direction R and by the direction of the main axis P.
[0070] Furthermore, each first interface region 15 is intended to come into contact, in a contact direction, denoted C, and represented for example in FIGS. 1 to 3, with a second interface region 20.
[0071] The contact direction C is notably perpendicular to the interface plane.
[0072] The first and second interface regions 15, 20 extend, for example, in projection in the radial direction R, over a distance greater than or equal to 0.2 mm.
[0073] The or each first interface region 15 extends opposite the or each second interface region 20 in the contact direction C.
[0074] In one embodiment, the first and second half-shells 5, 10 have a thickness, outside the first and second interface regions 15, 20, measured in a radial direction R, greater than or equal to 0.5 mm.
[0075] In this same embodiment, the first and second half-shells 5, 10 have a thickness, at the level of the first and / or second interface regions 15, 20, measured in the radial direction R passing through these interface regions, greater than or equal to 0.5 mm.
[0076] In the embodiment shown in [Fig.l], the first and second half-shells 5, 10 each comprise two interface regions 15, 20 extending in projection in the radial direction R towards the outside of the conduit 1.
[0077] In the example, the first and second interface regions 15, 20 extend on either side of the conduit 1.
[0078] In the example of [Fig.l], the first interface regions 15 are distributed over the circumference of the first half-shell 5, for example diametrically opposite one another, relative to the central axis O of the conduit 1, one of the first interface regions 15 extending along the peripheral edge 5A, the other of the first interface regions 15 extending along the peripheral edge 5B.
[0079] Similarly, the second interface regions 20 are distributed over the circumference of the second half-shell 10, for example diametrically opposite one another, relative to the central axis O of the conduit 1, one of the second interface regions 20 extending along the peripheral edge 10A, the other of the second interface regions 20 extending along the peripheral edge 10B.
[0080] With reference to [Fig.2], the interface regions 15, 20 will now be described in more detail.
[0081] Each first interface region 15 is formed by a planar contact surface 25.
[0082] The contact surface 25 extends over a plane containing the main axis P and the radial direction R of extension of the interface regions 15, 20.
[0083] By “planar contact surface”, it is meant that when the second interface region 20 is in contact with the first interface region 15, that is to say when the first half-shell 5 is assembled with the second half-shell 10 in order to form the conduit 1, the surface 25 forming the contact between the first and second interface regions 15, 20 is planar.
[0084] In other words, the first interface regions 15 do not have a particular geometry configured so that when the first half-shell 5 is assembled with the second half-shell 10 in order to form the conduit 1, the second interface region 20 is fitted into the first interface region 15.
[0085] Each second interface region 20 is formed by a planar portion 28, as visible for example in FIGS. 2 to 4.
[0086] The or each planar portion 28 extends over a plane containing the main axis P and the radial direction R of extension of the interface regions 15, 20.
[0087] For example, the or each planar portion 28 extends parallel to the or each planar contact surface 25 opposite, in the contact direction C.
[0088] As visible in [Fig.2], the second half-shell 10 comprises at least one protuberance 30 extending in projection from the or each second interface region 20 towards the first interface region 15. More particularly, the protuberance 30 extends in projection from the flat portion 28.
[0089] For example, the protrusion 30 projects from the or each second interface region 20 in the contact direction C, and has for example, without being limited to, the shape of a bump having a semi-circular section.
[0090] According to one embodiment, the protuberance 30 projects from the or each flat portion 28, in the contact direction C, by a distance greater than or equal to 0.2 mm.
[0091] Each protuberance 30 is applied to a part of the flat contact surface 25 in order to ensure the sealing of the conduit 1 by contact between the protuberance 30 and the flat contact surface 25.
[0092] Thus, the protrusions 30 keep the or each flat portion 28 away from the or each opposite flat contact surface 25, in the contact direction C.
[0093] For this purpose, each protuberance 30 projects from the flat portion 28 of the or each second interface region 20, over the entire length, taken along the main axis P, of the second half-shell 10.
[0094] In the embodiment shown in [Fig.2], the second half-shell 10 comprises two protrusions 30 projecting from the flat portion 28 of the or each second interface region 20.
[0095] The protuberances 30 are then applied to a part of the flat contact surface 25 of the first half-shell 5, in order to ensure the sealing of the conduit 1 by contact between the protuberances 30 and the flat contact surface 25.
[0096] In this embodiment, the two protuberances 30 are spaced from each other in the radial direction R, and extend, for example, on either side of the flat portion 28 in the radial direction R.
[0097] More precisely, in the example shown, the second half-shell 10 comprises a first protuberance 30 extending at the end 10A projecting from the flat portion 28 towards the first interface region 15, and a second protuberance 30 extending at the end of the second interface region 20 in the radial direction R, projecting from the flat portion 28 towards the first interface region 15.
[0098] In a variant, not shown, the second half-shell 10 comprises more than two protuberances 30 projecting from the flat portion 28, each protuberance 30 being applied to a part of the flat contact surface 25 of the first half-shell 5, in order to ensure the sealing of the conduit 1 by contact between the protuberances 30 and the flat contact surface 25.
[0099] According to one embodiment, at least the second interface region 20 comprises at least one fixing zone 35 comprising a fixing tab 40 extending in projection from the second interface region 20 in the contact direction C.
[0100] In the example shown in Figures 3, 4, 6 and 7, only the second interface region 20 comprises at least one fixing zone 35.
[0101] For example, the second interface region 20 comprises a plurality of fixing zones 35 spaced from one another along the main axis P, by a distance of between 1 cm and 25 cm, preferably between 3 cm and 8 cm.
[0102] Between each fixing zone 35 the second interface region 20 is then as described above, with reference to [Fig.2].
[0103] The or each fixing zone 35 has a length, taken along the main axis P, for example greater than or equal to 10 mm.
[0104] Each fixing zone 35 is located opposite a part of the first interface region 15, in the contact direction C.
[0105] The fixing lug 40 extends between a first end 40A linked to the fixing zone 35 and a free end 40B, opposite the first end 40A in a longitudinal direction substantially perpendicular to the radial direction R.
[0106] More precisely, the first end 40A is linked to the planar portion 28 of the second interface region 20.
[0107] For example, as shown in Figures 3, 4 and 7, the longitudinal direction coincides with the main axis P.
[0108] Alternatively, the longitudinal direction forms a non-zero angle with the main axis P, in a plane perpendicular to the radial direction R.
[0109] This angle is advantageously chosen as a function of the main axis P, that is to say as a function of the geometry of the conduit 1, straight or curved.
[0110] For example, when the conduit 1 is of bent shape, having a curved main axis P, more precisely forming an angle of approximately 90°, the longitudinal direction can be chosen so as to form an angle substantially equal to 45° with each straight portion of the main axis P, in a plane containing each straight portion of the main axis P, so as to accommodate the different directions of extension of the conduit 1 and to simplify the injection molding of the half-shells 5, 10.
[0111] Generally speaking, the longitudinal direction can be chosen in an optimized manner for each type of conduit, straight, curved, sinuous, etc.
[0112] The free end 40B of the fixing lug 40 extends away from the fixing zone 35 in the contact direction C.
[0113] When the first half-shell 5 is assembled with the second half-shell 10, the fixing tab 40 is fixed to the first interface region 15.
[0114] The or each fixing lug 40 is advantageously made in one piece with the second half-shell 10.
[0115] The or each fixing lug 40 comprises an internal face 41 and an external face 42 opposite the internal face 41 in the contact direction C.
[0116] The internal face 41 extends substantially parallel to the second interface region 20.
[0117] The internal face 41 extends between the second interface region 20 and the external face 42.
[0118] The external face 42 extends substantially parallel to the internal face 4L
[0119] The free end 40B extends the internal 41 and external 42 faces in a direction inclined relative to the longitudinal direction and relative to the contact direction C, in a plane containing the longitudinal direction and the contact direction C.
[0120] The or each fixing zone 35 comprises a window 44, visible in FIGS. 4 and 7, extending at least opposite the free end 40B of the fixing lug 40.
[0121] The or each window 44 is for example a rectangular through window extending into the second interface region 15.
[0122] By "through" we mean that the window 44 starts from the flat portion 28 and opens out on the other side of the fixing zone 35 by crossing the thickness, taken along the contact direction C, of the fixing zone 35.
[0123] The or each window 44 has a length, taken along the main axis P, for example greater than or equal to 5 mm.
[0124] In the embodiment shown, the window 44 extends opposite at least the internal face 41 and the free end 40B.
[0125] In other words, the window 44 extends opposite the fixing lug 40, except where the fixing lug 40 is linked to the fixing zone 35, that is to say at its end 40A.
[0126] Thus, the window 44 present on the second interface region 20 simplifies the manufacturing, in particular the demolding, of the second half-shell 10 and thus makes it possible to minimize the production costs.
[0127] More particularly, the presence of such a window 44 makes it possible to produce the second half-shell 10 by injection molding without using a movable drawer in order to unmold the fixing tab 40.
[0128] A passage opening 45, visible in figures 5 and 7, of the fixing lug 40 is provided in the or each part of the first interface region 15 opposite the or each fixing zone 35 of the second half-shell 10.
[0129] The or each passage opening 45 is for example a rectangular through window extending into the first interface region 15.
[0130] By “through” is meant that the passage opening 45 starts from the flat contact surface 25 and opens out on the other side of the first interface region 15 by crossing the thickness, in the contact direction C. When the first half-shell 5 is assembled with the second half-shell 10, the fixing lug 40 passes through the passage opening 45 and is fixed to the first interface region 15, through the passage opening 45.
[0131] In one embodiment, the or each part of the first interface region 15 opposite the or each fixing zone 35 of the second half-shell 10 has a U-shaped or L-shaped section, in a plane perpendicular to the main axis P.
[0132] In other words, and with reference to figures 5 and 6, the or each part of the first interface region 15 opposite the or each fixing zone 35 has a first branch 47 extending in projection in the radial direction R, substantially perpendicular to the main axis P, towards the outside of the conduit 1, and a second branch 48 extending the first branch 47 in projection in the contact direction C.
[0133] In one embodiment, and in order to robustly maintain the first half-shell 5 assembled with the second half-shell 10, the or each part of the first interface region 15 opposite the or each fixing zone 35 of the second half-shell 10 comprises a projecting element 50, visible in [Fig.7], cooperating with the fixing lug 40.
[0134] For this purpose, the free end 40B of the fixing lug 40 comprises a boss 55 projecting from the internal face 41, towards the second interface region 20.
[0135] Advantageously, the or each fixing lug 40 is elastically deformable between a first position, in which the free end 40B is located at a first distance from the second interface region 20 along the contact direction C, and a second position in which the free end 40B is located at a second distance from the second interface region 20 along the contact direction C, the second distance being greater than the first distance.
[0136] This characteristic allows the boss 55, when a user translates one of the first or second half-shells 5, 10 along the main axis P, to be engaged against the projecting element 50.
[0137] In addition, as shown in [Fig.7], a fixing tab portion 40 then abuts against one end of the passage opening 45.
[0138] Thus, the cooperation of the boss 55 with the projecting element 50, and of the fixing lug 40 with the passage opening 45, blocks any translational movement along the main axis P of the fixing lug 40, and more generally of the second half-shell 10 respectively to the first half-shell 5.
[0139] Furthermore, the elasticity of the fixing lug 40 allows it to return to its initial position when the two half-shells 5, 10 are disassembled from each other.
[0140] Thus, this characteristic facilitates on the one hand assembly, but also disassembly and makes it possible to carry out assembly and disassembly cycles without generating residual deformation which would alter the fixing system of the half-shells 5, 10.
[0141] Furthermore, the engagement of the fixing lug 40 in the passage opening 45 reinforces the assembly in the radial direction R of the first and second half-shells 5, 10.
[0142] In one embodiment, the first half-shell 5 comprises at least one reinforcing rib 60 extending between the external wall of the duct 1 and the first interface region 15 and / or the second half-shell 10 comprises at least one reinforcing rib 65 extending between the external wall of the duct 1 and the second interface region 20.
[0143] More particularly, the first half-shell 5 comprises at least one reinforcing rib 60 extending between the external face 6B of the wall 6 and the first interface region 15, and the second half-shell 10 comprises at least one reinforcing rib 65 extending between the external face 7B of the wall 7 and the second interface region 20.
[0144] These reinforcing ribs 60, 65 support the geometry of the interface regions 15, 20 in order to reinforce the structure and to avoid any permanent deformation of each interface region 15, 20.
[0145] The ribs 60, 65 are of even greater interest when the or each part of the first interface region 15 opposite the or each attachment zone 35 of the second half-shell 10 has a U-shaped or L-shaped section as described above.
[0146] In the embodiment shown in [Fig. 2], the interface regions 15, 20, outside the fixing zones 35 and the parts of the first interface region 15 facing the fixing zones 35, do not necessarily have reinforcing ribs 60, 65.
[0147] Alternatively, the reinforcing ribs 60, 65 extend regularly along the entire length of the interface regions 15, 20, taken along the main axis P.
[0148] By “regularly”, it is meant that the reinforcing ribs 60, 65 are arranged along the interface regions 15, 20 in a spaced manner so as to frame, along the main axis P, the fixing zones 35.
[0149] For example, the reinforcing ribs 60, 65 may be spaced from each other along the main axis P, by a distance greater than or equal to the spacing along the main axis P of the fixing zones 35 between them.
[0150] The ribs 60, 65 have, for example, a thickness, taken along the main axis P, greater than or equal to 0.5 mm.
[0151] A method of assembling such a conduit 1 will now be described.
[0152] A user initially has the first half-shell 5 and the second half-shell 10. The user brings the first half-shell 5 into contact with the second half-shell 10 by bringing them closer to each other so that the edges 5A, 5B of the first half-shell 5 come into contact with the edges 10A, 10B of the second half-shell 10.
[0153] Thus, the or each first interface region 15 is located opposite the or each second interface region 20, in the contact direction C.
[0154] In order to form the sealed conduit 1, the user places the or each passage opening 45 opposite the or each fixing zone 35.
[0155] By a movement in the contact direction C, the user passes the or each fixing lug 40 into the or each passage opening 45 provided for this purpose.
[0156] The or each protuberance 30 of the or each second interface region 20 is then in contact with the or each flat contact surface 25 of the first half-shell 5.
[0157] The conduit 1 thus formed is then a conduit with a closed section, the sealing of which is ensured by the contact between the or each protuberance 30 and the or each flat contact surface 25.
[0158] In order to securely hold the first half-shell 5 fixed to the second half-shell 10, the user translates one of the half-shells 5, 10 along the main axis P of so as to engage the boss 55 of the fixing lug 40 against the element 50.
[0159] By elastic deformation of the fixing lug 40, the latter passes from the first position in which the free end 40B is located at a first distance from the second interface region 20 in the contact direction C, to the second position in which the free end 40B is located at a second distance from the second interface region 20 in the contact direction C, the second distance being greater than the first distance.
[0160] Once the boss 55 is engaged against the projecting element 50, the movement of the half-shells 5, 10 along the main axis P is blocked.
[0161] The conduit 1 is then robustly assembled and sealed.
[0162] In order to disassemble the conduit 1, the user performs the previous steps in reverse order.
[0163] It first disengages the fixing lug 40 from the first interface region 15 by deforming the fixing lug 40 to disengage the boss 55 from the projecting element 50.
[0164] Then, the user translates one of the half-shells 5, 10 along the main axis P and, in a movement parallel to the contact direction C, disengages the fixing lug 40 from the passage opening 45.
[0165] Finally, the user can simply move one half-shell 5, 10 away from the other half-shell 5, 10 in a direction parallel to the contact direction C.
[0166] In a variant, not shown, the conduit 1 is as described above with a layer of foam inserted between the two half-shells 5, 10, between the first and second interface regions 15, 20.
[0167] Advantageously, this layer of foam allows the absorption of mechanical play and / or shocks which could damage the conduit 1.
[0168] The air duct 1 according to the invention has numerous advantages.
[0169] The sealing of the conduit 1 is ensured by the contact between the or each protuberance 30 projecting from the or each second interface region 20 with the or each flat contact surface 25.
[0170] The assembly of the conduit 1 is simplified in that there is no need to fit the first half-shell 5 with the second half-shell 10 by cooperation of complementary shapes.
[0171] The user therefore does not have to look for the interface regions 15, 20 of each half-shell 5, 10 and make them coincide in order to correctly fit the half-shells 5, 10 and ensure the sealing of the conduit 1. Thus, even when the conduit has a complex shape, in particular when it extends along a non-rectilinear axis, the assembly of the conduit remains simple.
[0172] The user only has to translate one of the half-shells 5, 10 onto the other half-shell 5, 10 in order to engage the or each fixing lug 40 in the or each passage opening 45 and to fix the first half-shell 5 on the second half-shell 10.
[0173] This step is intuitive and does not require great visual precision on the part of the user who is guided by the cooperative shape of the interface regions, which is all the more advantageous when the conduit is of complex shape.
[0174] Furthermore, the conduit 1 as described facilitates disassembly of the conduit 1 in the same way that it facilitates assembly.
[0175] This assembly technique allows the manufacture and use of thin half-shells which are thus lighter and minimize the total weight of the vehicle in which they are placed.
[0176] The conduit thus formed is robust and watertight, its geometry is notably ensured by the reinforcing ribs which minimize the deformations of the interface regions.
[0177] The conduit is then resistant, even under radial pressure stress due to the circulation of a fluid inside the conduit.
[0178] Furthermore, when such a conduit is produced by an injection process, this allows the integration of other characteristics and functionalities into the conduit (such as an electronic component interface, or a layer of foam absorbing mechanical play and / or sound waves), which would be difficult to envisage with a blow-molding manufacturing process.
Claims
Claims
1. Air duct (1) comprising a first half-shell (5) and a second half-shell (10) together forming a duct (1) with a closed section suitable for the circulation of a fluid, said duct (1) extending along a main axis (P), the first half-shell (5) comprising at least one first interface region (15) and the second half-shell (10) comprising at least one second interface region (20), the first and second interface regions (15, 20) extending projecting in a radial direction (R), substantially perpendicular to the main axis (P), towards the outside of the duct (1), the or each first interface region (15) extending opposite the or each second interface region (20) in a contact direction (C), characterized in that the or each first interface region (15) is formed by a flat contact surface (25),the second half-shell (10) comprising at least one protuberance (30) projecting from the or each second interface region (20), said protuberance (30) being applied to a part of the flat contact surface (25) in order to ensure the sealing of the conduit (1) by contact between the protuberance (30) and the flat contact surface (25).,
2. Air duct (1) according to claim 1, wherein the second half-shell (10) comprises two protrusions (30) projecting from the or each second interface region (20), said protrusions (30) being applied to a part of the flat contact surface (25) of the first half-shell (5), in order to ensure the sealing of the duct (1) by contact between the protrusions (30) and the flat contact surface (25), the protrusions (30) being spaced from each other in the radial direction (R).
3. Air duct (1) according to claim 1 or 2, wherein the first and second half-shells (5, 10) have a thickness, outside the first and second interface regions (15, 20), taken parallel to the radial direction (R), greater than or equal to 0.5 mm and / or the first and second half-shells (5, 10) have a thickness, at the first and / or second interface regions (15, 20), taken parallel to the radial direction, greater than or equal to 0.5 mm.
4. An air duct (1) according to any preceding claim, wherein the first and second half-shells (5, 10) each comprise two interface regions (15, 20) extending in projection in the radial direction (R) towards the outside of the conduit (1), said interface regions (15, 20) extending on either side of the conduit (1).
5. Air duct (1) according to any one of the preceding claims, wherein at least the second interface region (20) comprises at least one fixing zone (35) comprising a fixing lug (40) extending projecting from the second interface region (20) in the contact direction (C), the fixing lug (40) extending between a first end (40A) linked to the fixing zone (35) and a free end (40B), opposite the first end (40A) in a longitudinal direction substantially perpendicular to the radial direction (R), the fixing lug (40) being fixed to the first interface region (15).
6. Air duct (1) according to claim 5, in which a passage opening (45) for the fixing lug (40) is provided in the or each part of the first interface region (15) opposite the or each fixing zone (35) of the second half-shell (10), the fixing lug (40) passing through said opening (45) to be fixed to the first interface region (15).
7. Air duct (1) according to claim 5 or 6, wherein the or each part of the first interface region (15) opposite the or each fixing zone (35) of the second half-shell (10) comprises a projecting element (50) cooperating with the fixing lug (40) in order to reversibly fix the first half-shell (5) on the second half-shell (10).
8. Air duct (1) according to any one of claims 5 to 7, in which the or each fixing zone (35) comprises a window (44) extending at least opposite the free end (40B) of the fixing lug (40).
9. Air duct (1) according to any one of claims 5 to 8, in which the or each part of the first interface region (15) opposite the or each fixing zone (35) of the second half-shell (10) has a U-shaped or L-shaped section, in a plane perpendicular to the main axis (P).
10. Air duct (1) according to any one of claims 1 to 9, wherein the first half-shell (5) comprises at least one reinforcing rib (60) extending between the wall of the duct (1) and the first interface region (15) and / or the second half-shell (10) comprises at least a reinforcing rib (65) extending between the wall of the conduit (1) and the second interface region (20).