Motor vehicle with underfloor air deflector

Abstract

The invention relates to a motor vehicle comprising a structure including a subframe (14) and a side member (16) with an internal chamber comprising a lower wall (26). The motor vehicle further includes a deflector (20), such as an air deflector, under the subframe (14). The lower wall (26) includes a plurality of liquid flow orifices (30), and the deflector (20) includes fastening means (40) fixed in the flow orifices. The invention also proposes a method for manufacturing a vehicle with a coating application by cataphoresis and flow of cataphoresis liquid through the flow orifices (30) before sealing by the sealing means. Figure to be published with the abbreviation: Fig. 3

Description

Title of the invention: Motor vehicle with underfloor air deflector

[0001] The invention relates to the attachment of a deflector under a vehicle. More specifically, the invention deals with a motor vehicle comprising a structure and a deflector attached under the structure.

[0002] Motor vehicles comprise a structure (or body) having an underbody extending in longitudinal and transverse directions. The underbody has a lower face to which at least one piece of equipment is fixedly attached, such as, for example, an exhaust system or an electric battery itself equipped with dedicated components.

[0003] This structure is generally masked by a deflector which is fixedly attached to its lower face and which is generally designed to reduce aerodynamic drag and therefore energy consumption, and is consequently frequently referred to as "aerodynamic". This fixed attachment is achieved by screwing using nuts, at least some of which are previously welded or glued, above holes, to an upper face of a first transverse edge defined at a lower end of the structure and to which a second transverse edge of the deflector must be fixedly attached.

[0004] Document FR3099744_Bl discloses a motor vehicle comprising a subframe having a first lower face to which a structure housing equipment is fixedly attached and having a lower end defined by a first transverse edge. An air deflector covers the subframe. This deflector includes a second transverse edge having N holes, through which N screws pass, fixedly attaching it to the first transverse edge. In addition, the deflector has several upward-facing shims surrounding the holes, which receive nuts. This arrangement allows for longitudinal and transverse shimming of the second transverse edge relative to the first when positioning the deflector with respect to the structure. The operator's work is thus simplified.

[0005] However, such a method of attachment requires the addition of specific fastening means to the vehicle structure. These fastening means necessitate certain adaptations and specific operations, which generate additional costs. Furthermore, the retention of the deflector's lateral edges remains limited. The deflector's coverage remains minimal.

[0006] The invention aims to address at least one of the problems or drawbacks encountered in the prior art. In particular, the invention aims to The invention aims to reduce the manufacturing costs of a motor vehicle. It also seeks to optimize the protection of a chassis rail and the manufacturing costs of a motor vehicle.

[0007] According to a first aspect, the invention proposes a motor vehicle comprising a structure including a subframe, and a side member with an internal chamber which includes a lower wall, the motor vehicle further comprising a deflector under the subframe, notable in that the lower wall includes at least one liquid flow orifice, and in that the deflector includes fastening means cooperating with the or at least one of the flow orifices for the fastening of the deflector to the lower wall.

[0008] It will be clearly understood that the invention proposes a motor vehicle comprising a subframe with a side member which delimits an internal chamber with a lower end, also called the low point or low zone, the motor vehicle further comprising a deflector covering the subframe, remarkable in that the lower end or the low zone includes an evacuation, for example formed by one or more liquid evacuation orifices, and the deflector includes fastening means cooperating with the evacuation for the fastening of the deflector to the subframe.

[0009] The invention uses a liquid flow orifice to which the deflector is attached. The flow orifice facilitates the evacuation of a functional liquid that forms a coating in the internal chamber. Thus, this orifice has a dual function. The number of means specific to the structure for attaching the deflector is reduced since the invention uses means already employed in a previous manufacturing step.

[0010] The fastening means contribute to sealing the openings. Thus, they replace plugs. Here again, the invention introduces a dual-function concept since the fastening means have both a fastening function and a protective function for the side member by preventing impurities from entering the internal chamber. As a reminder, impurities present on the road have chemical and abrasive activity. Their accumulation in a cavity tends to deteriorate the cavity. Therefore, the features of the invention prevent these impurities from entering, thus protecting the side member.

[0011] Preferably, the drainage orifice(s) have an oblong shape with a main elongation arranged along a longitudinal direction of the motor vehicle; and the fastening means include at least one fastening element having an oblong shape and snap-on tabs intended to be inserted into the drainage orifice(s).

[0012] Preferably, the fastening means comprise sealing means configured to hermetically seal the opening or at least one of the orifices flow.

[0013] Preferably, the at least one drainage orifice comprises a plurality of drainage orifices distributed along the side member, the motor vehicle further comprising a shutter sealing one of the drainage orifices of the plurality of drainage orifices, said shutter being at a distance from the fastening means.

[0014] Preferably, the deflector comprises a lower surface and an edge raised relative to the lower surface, the fastening means being arranged along said edge.

[0015] Preferably, the chamber comprises a lower end, with at least one discharge orifice being at said lower end.

[0016] Preferably, the deflector comprises a lower face and at least one fixing opening, the fixing means being inserted into the at least one fixing opening; and the sealing means comprise a sealing lip cooperating hermetically with the lower face.

[0017] Preferably, the or at least one of the fixing openings coincides with the or at least one of the drainage orifices.

[0018] Preferably, the longeron is a lateral longeron transversely delimiting a floor.

[0019] Preferably, the internal chamber has an internal surface with a coating.

[0020] Preferably, the flow ports are distributed longitudinally over the majority of the length of the spar.

[0021] Preferably, the deflector covers the lower wall.

[0022] Preferably, the flow ports of the plurality of flow ports forming an alignment along the spar.

[0023] According to another aspect, the invention provides a deflector for a motor vehicle according to the invention and at least one drainage orifice has an oblong shape with a main elongation arranged along a longitudinal direction of the motor vehicle; and the fastening means comprise at least one fastening element having an oblong shape and snap-on tabs introduced into the drainage orifice, the deflector comprising a main direction, notable in that the deflector comprises a lateral edge with a plurality of fastening openings, and fastening means inserted into the plurality of fastening openings of the lateral edge, the fastening means comprising at least one fastening element of oblong shape with a main elongation arranged along the main direction.

[0024] Preferably, the deflector further comprises at least one stiffening profile arranged along the longitudinal direction.

[0025] According to another aspect, the invention proposes a method for manufacturing a motor vehicle remarkable in that the motor vehicle conforms to the invention, and the manufacturing method comprises the following steps: immersion of the structure in a bath with a coating liquid, and filling of the internal chamber with said coating liquid; formation of a coating in the internal chamber of the side member with the coating liquid; evacuation of the coating liquid in the internal chamber through at least one drainage orifice; then fixing of the deflector by insertion of the fixing means into said at least one drainage orifice.

[0026] Preferably, at the immersion stage, the bath is a cataphoresis bath.

[0027] In general, the invention proposes a method for manufacturing a vehicle at tomobile with a coating formation by immersion in at least one bath, and flows of at least one liquid through the fixing orifices in both directions; before sealing said fixing orifices by means of fixing a deflector during the fixing of said deflector.

[0028] The invention will be well understood and other aspects and advantages will become clear upon reading the following description given with reference to the attached figures listed below.

[0029] [Fig.1] Fig.1 is a side view of a vehicle according to the invention.

[0030] [Fig.2] Fig.2 is a view from below of a vehicle underbody. tomobile according to the invention.

[0031] [Fig.3] The [Fig.3] is a view of the underside of the underbody of a motor vehicle with a deflector according to the invention.

[0032] [Fig.4] Fig.4 shows means of fixing a deflector of a motor vehicle according to the invention.

[0033] [Fig.5] Fig.5 represents a diagram of a manufacturing process for a motor vehicle according to the invention.

[0034] In the following description, the term "include" is synonymous with "include" and is not limiting in that it permits the presence of other elements in the motor vehicle to which it relates. It is understood that the term "include" includes the terms "consist of". The terms "external" and "internal" shall respectively designate what is oriented towards the outside of the vehicle and towards the inside of the vehicle.

[0035] Similarly, the terms "lower", "upper", "high" and "low" shall be understood according to their usual definition, in which the terms "lower" and "low" indicate a greater proximity to the ground in the vertical direction than respectively the terms "higher" and "high".

[0036] In this description, the term “longitudinal”, the term "Longitudinally", the term "transversely", and the term "transversely" are Used according to the vehicle's reference frame, in the mounting configuration. The term "longitudinal" corresponds to the vehicle's primary direction of travel. The term "transverse" corresponds to a direction perpendicular to the vehicle's primary direction of travel. The term "front" refers to the vehicle's primary direction of travel. The term "rear" designates the opposite of the front of the vehicle. The X-axis represents the longitudinal direction, the Y-axis represents the transverse direction, and the Z-axis represents the vertical direction.

[0037] Throughout the description, the different figures use the same reference signs to designate identical or similar entities.

[0038] Figure 1 shows a motor vehicle 10 according to the invention. The motor vehicle 10 is shown in side view, along the transverse direction, along the Y axis. The arrow on the X axis is directed towards the front of the vehicle.

[0039] The motor vehicle 10 comprises a structure 12 with a subframe 14 and two longitudinal members 16 (only one visible). The longitudinal members 16 extend along the side doors. The longitudinal members 16 may be side members. The longitudinal members 16 extend along the passenger compartment. They stiffen the structure and connect the front axle to the rear axle. The longitudinal members 16 are hollow to reduce their weight while optimizing the rigidity they provide.

[0040] The subframe 14 forms the lower part of the structure 12. The subframe can be the base of the structure. The subframe 14 is covered by a deflector 20. The deflector 20 faces the surface on which the vehicle 10 travels.

[0041] The deflector is also called an aerodynamic deflector. The deflector 20 is also referred to as an air deflector, or bottom fairing. The deflector 20 forms a panel covering the structure 12. The deflector 20 is generally a component that modifies the airflow under the vehicle. It reduces the drag of the motor vehicle 10, thereby decreasing the primary energy required to power the drive motor(s).

[0042] The deflector 20 extends longitudinally between the axles, for example over part of the distance between the axles, or over the entire wheelbase. It may extend beyond the axles.

[0043] The deflector 20 covers equipment forming protrusions capable of slowing the airflow between the ground and the vehicle while it is moving. This equipment may include an exhaust system and / or electric batteries. The lower surface of the deflector 20 is optionally profiled to further limit the generation of turbulence when the motor vehicle 10 is moving.

[0044] Figure 2 shows a motor vehicle viewed from below in order to expose its underbody 14. The motor vehicle preferably conforms to that shown in Figure 1. The deflector is omitted for clarity.

[0045] The underbody 14 has a floor 22 which delimits the passenger compartment (not shown) and in particular a rear cargo space such as a trunk. Two door openings 24 are visible. The floor 22 is delimited transversely by the longitudinal members 16.

[0046] For the sake of clarity, the description will focus on one of the two longerons. However, each characteristic defined in relation to one of the two lateral longerons also applies to the other.

[0047] The side member 16 connects the floor 22 to the door openings 24. It can be made of stamped sheets welded together. The side member 16 has an internal chamber (not shown). The internal chamber is delimited by a lower wall 26, two side walls 27 (only one visible), and an upper wall.

[0048] The lower wall 26 is generally horizontal. It extends longitudinally and transversely. It is formed by a sheet of the longeron 16. The lower wall 26 may include at least one lower end 28, and possibly a plurality of lower ends 28 at the same height. The lower ends 28 may be arranged in a horizontal line. A lower end is generally considered to be a low point, in that it forms the bottom of the chamber. A liquid reaches this point by gravity.

[0049] The lower wall 26 includes flow means, in particular liquid discharge means. The liquid discharge means include at least one discharge orifice 30, preferably several discharge orifices 30. The discharge orifices 30 may be gravity discharge orifices. The discharge orifices 30 pass through the lower wall 26. They allow flow between the internal chamber and the environment. The discharge orifices 30 allow liquid to flow in both directions. Thus, when the structure 12 is immersed in a bath, the liquid enters and then exits the internal chamber via the discharge orifices 30. The internal surface of the internal chamber is thus coated with a protective finish, in particular by cataphoresis.

[0050] The cataphoresis aspect is not an essential aspect of the invention. At least one orifice may include a runoff water outlet.

[0051] The flow ports 30 form an alignment. They are distributed along the lateral spar 16, for example over most of its length, to optimize the drainage of a fluid present in the internal chamber. In the present embodiment, the internal surface comprises seven flow ports 30. However, the invention considers any other number of flow ports 30 adapted to the length of the corresponding spar.

[0052] At least one of the flow orifices 30 is disposed at at least one low point 28. Preferably, each flow orifice 30 is associated with one of the low points 28. This configuration improves the gravitational evacuation of a liquid into the internal chamber.

[0053] Fig. 3 shows the underbody of Fig. 2 equipped with deflector 20. A rear wheel arch is visible.

[0054] The deflector 20 includes fastening means 40 attached to the side member 16. The fastening means 40 secure the deflector 20 to the lower wall 26. They cooperate with at least one, preferably several, of the drainage ports 30. The fastening means 40 include at least one, preferably several, of the fastening elements 42. The fastening elements may be snap-on clips. The fastening elements 42 are inserted into the drainage ports 30. The fastening elements 42 form a line. The fastening elements 42 may be identical.

[0055] The fastening means 40 are arranged on a lateral edge 44 of the deflector 20. The lateral edge 44 may be a fastening edge. The upper surface of the lateral edge 44 conforms to the lower face of the lower wall 26. The lateral edge 44 extends longitudinally along most of the lateral stringer 16. A section of the lateral stringer 16 is free of the deflector 20. The deflector 20 remains at a distance from one of the drainage ports 30, for example, the rear drainage port 30. The latter is optionally covered by an attached plug 46. The plug 46 may be an adhesive.

[0056] Thus, the combination of the fastening means 40 and the shutter 46 makes it possible to close the internal chamber, or at least to form a barrier between the internal chamber and the ground. This prevents impurities from entering the internal chamber through the openings.

[0057] The shutter 46 is preferably watertight. The fastening means 40 include sealing means. The sealing means cooperate with the lower surface 48 of the deflector 20. The lower surface 48 and the lateral edge 44 form the lower face 49 of the deflector 20. Thus, the internal chamber is hermetically sealed from its environment. After a coating liquid has flowed through the flow orifices 30, the internal chamber is hermetically sealed. Thus, the invention prevents moisture from entering the internal chamber.

[0058] The lower surface 48 is oriented downwards. The lower surface 48 faces the ground. The lower surface 48 is below the lateral edge 44. This arrangement protects the fastening means 40.

[0059] According to an alternative not shown of the invention, the deflector 20 extends over the entire lower wall 26 and passes through all the flow orifices 30. Preferably, the fastening means 40 are introduced into each flow orifice 30.

[0060] The deflector 20 extends transversely from the longeron 16 towards the inside of the vehicle. It covers the exhaust line. It has a smooth surface. It extends over substantially the entire length of the side member 16. It has a main direction 21 along the longitudinal direction of the vehicle, i.e. along the X axis.

[0061] The deflector 20 comprises at least one fixing opening, preferably several fixing openings receiving the fixing means 40. The fixing openings coincide with the drainage orifices 30. They have similar or identical contours. The fixing means 40 close the fixing openings, preferably in a watertight manner.

[0062] Figure 4 shows a fastening element 42 of the fastening means 40 for a motor vehicle deflector. The motor vehicle corresponds to those described in relation to one of Figures 1 to 3.

[0063] The fastening element 42 comprises a body 50. The body 50 generally has an oblong, or possibly rectangular, shape. The shape of the body allows it to be locked against rotation about the Z-axis, to improve stability. The shape of the body 50 is complementary to the contour of the fastening holes in the lower wall of the spar; and also complementary to the contour of the fastening openings in the lateral edge of the deflector. Thus, the body 50 closes the fastening opening and the drainage orifice through which it passes.

[0064] The fastening element 42 includes snap-on means. The snap-on means include at least one snap-on tab 52. Each snap-on tab 52 has a flexible portion extending from the body 50, and a retaining stop to hold the fastening element 42 in a flow orifice.

[0065] The fastening element 42 advantageously includes sealing means. These sealing means include a sealing lip 54. Each sealing lip 54 is adapted to come into contact with the lateral edge of the deflector, against the underside of the deflector. The sealing lip 54 has an oblong contour. It is intended to surround the contour of an associated drainage orifice.

[0066] Optionally, the fastening element 42 includes a sealing plate 56. The sealing plate 56 is arranged at one end of the body 50. It has an oblong shape. The sealing lip 54 forms a rim on the sealing plate 56.

[0067] The sealing plate is not an essential aspect of the invention. According to one embodiment of the invention, the sealing lip is formed directly on the body of the fastening element.

[0068] The fastening element 42 has a principal elongation 58. The principal elongation 58 of the fastening element 42 can correspond to the longitudinal direction of the motor vehicle. The longitudinal direction is parallel to the X-axis. The holes The flow paths also exhibit a main elongation along the longitudinal direction, i.e., along the spar. This allows for better emptying of the inner chamber when it contains liquid.

[0069] The present description is given in relation to a fastening element 42. However, the characteristics presented above also apply to each fastening element of the deflector.

[0070] Figure 5 shows the diagram of the manufacturing process of the motor vehicle according to the invention.

[0071] The process comprises the following steps, preferably carried out in the following order.

[0072] Immersion 100 of the structure in a bath with a coating liquid and filling of the internal chamber with said coating liquid.

[0073] Formation 102 of a coating in the internal chamber of the longeron with the coating liquid.

[0074] Evacuation 104 of the coating liquid into the internal chamber through at least one drain orifice.

[0075] Drying 106 of the structure.

[0076] Hardening 108 of the deposit in order to form a protective coating of the structure, and in particular inside the internal chamber.

[0077] Fixing 110 of the deflector by inserting the fixing means into said at least one drainage orifice.

[0078] Sealing 112 of one of the flow orifices using an added sealant.

[0079] During the immersion step 100, the structure is immersed in the bath so that its entire surface is in contact with the liquid. The internal chamber of the spar fills with the liquid entering through the flow port(s). The liquid also enters through other inlets at the longitudinal ends of the spar.

[0080] The bath is, for example, a water-soluble paint bath. It comprises suspended paint particles that come into contact with, and adhere to, the surface of the internal chamber.

[0081] The immersion step 100 can be an immersion step of the structure in a liquid bath comprising a coating precursor material.

[0082] The immersion 100 and training 102 steps can be carried out simultaneously.

[0083] The formation step 102 can be a coating formation step in the internal chamber using the precursor material.

[0084] At the formation step 102, the precursor material of the coating accumulates, aggregates on the surfaces of the structure, and in particular on the internal surface of the internal chamber.

[0085] After the formation step 102, the structure was removed from the bath. At the evacuation step 104, the internal chamber is emptied of the liquid present within it through the drain port(s). Due to the complex geometry of the spar, some liquid tends to remain trapped inside. Through each drain port, the liquid escapes from the chamber. The internal chamber empties more efficiently when the drain port is located at the lowest point of the internal chamber; preferably, each lowest point is associated with one of the drain ports.

[0086] The evacuation step 104 can be an evacuation step of liquid contained in the internal chamber through at least one discharge orifice.

[0087] The curing step 108 optionally includes passing the structure through an oven. The oven may have a temperature higher than ambient temperature, for example, a temperature greater than or equal to 100°C, or 180°C. This temperature allows polymerization of the coating.

[0088] The fastening step 110 is carried out after the drainage step 104, and preferably after the optional drying step 106 and the optional curing step 108. In the fastening step 110, the deflector is applied against the underbody, and the lateral edge of the deflector is aligned with the lower wall of the side member. Then, the deflector fastening means are attached to the drainage holes. The fastening elements are pushed through the drainage holes and locked into position.

[0089] The manufacturing step 112 is optional since the fastening means can close all the flow orifices when the deflector extends over all these orifices. It is clear that the greater the number of fastening elements, the fewer additional shutters are needed. Consequently, fewer assembly operations are required to protect the internal chamber.

[0090] Optionally, in the immersion step 100, the liquid bath is a cataphoresis bath. The structure advantageously comprises an electrically conductive material and is placed at the cathode. In the formation step 102, a current of a predefined voltage is applied. The paint particles then spread out into a uniform layer.

[0091] According to a variant of the invention, at the immersion stage the liquid bath is a varnish bath.

[0092] According to one embodiment of the invention, at the immersion stage the liquid bath is a passivation bath. Upon cooling, the precursor material solidifies.

[0093] According to one option of the invention, the immersion 100 and evacuation 104 steps are carried out with a passivation bath and then a cataphoresis bath.

Claims

Demands

1. Motor vehicle (10) comprising a structure (12) including a subframe (14), and a side member (16) with an internal chamber which includes a lower wall (26), the motor vehicle (10) further comprising a deflector (20) under the subframe (14), characterized in that the lower wall (26) includes at least one liquid drainage orifice (30), and in that the deflector (20) includes fastening means (40) cooperating with the or at least one of the drainage orifices (30) for fastening the deflector (20) to the lower wall (26).

2. Motor vehicle (10) according to claim 1, characterized in that the flow orifice(s) (30) have an oblong shape with a main elongation arranged along a longitudinal direction of the motor vehicle (10); and the fastening means (40) comprise at least one fastening element (42) having an oblong shape and snap-on tabs (52) intended to be inserted into the flow orifice(s) (30).

3. Motor vehicle (10) according to any one of claims 1 to 2, characterized in that the fastening means (40) comprise sealing means configured to hermetically close the or at least one of the drainage orifices (30).

4. Motor vehicle (10) according to claim 3, characterized in that the deflector (20) comprises a lower face (49) and at least one fixing opening, the fixing means (40) being inserted into the at least one fixing opening; and the sealing means comprise a sealing lip (54) cooperating hermetically with the lower face (49).

5. Motor vehicle (10) according to any one of claims 1 to 4, characterized in that at least one drainage orifice (30) comprises a plurality of drainage orifices (30) distributed along the side member (16), the motor vehicle (10) further comprising a shutter (46) sealing one of the drainage orifices (30) of the plurality of drainage orifices (30), said shutter (46) being at a distance from the fastening means (40).

6. Motor vehicle (10) according to any one of claims 1 to 5, characterized in that the deflector (20) comprises a lower surface (48) and an edge raised relative to the lower surface (48), the fastening means (40) being arranged along said edge.

7. Motor vehicle (10) according to any one of claims 1 to 6, characterized in that the chamber comprises a lower end (28), at least one discharge orifice (30) being at said lower end (28).

8. Deflector (20) for motor vehicle (10) according to any one of claims 2 to 7, the deflector (20) comprising a main direction (21), characterized in that the deflector (20) comprises a side edge (44) with a plurality of fixing openings, and fixing means (40) inserted in the plurality of fixing openings of the side edge (44), the fixing means (40) comprising at least one oblong-shaped fixing element with a main elongation (58) arranged along the main direction (21).

9. A method for manufacturing a motor vehicle (10) characterized in that the motor vehicle (10) conforms to any one of claims 1 to 7, and the manufacturing method comprises the following steps: immersion (100) of the structure (12) in a bath with a coating liquid, and filling of the internal chamber with said coating liquid; formation (102) of a coating in the internal chamber of the side member (16) with the coating liquid; evacuation (104) of the coating liquid in the internal chamber through at least one drainage orifice (30); then fixing (110) of the deflector (20) by inserting the fixing means (40) into said at least one drainage orifice (30).

10. Manufacturing process according to claim 9, characterized in that at the immersion step (100), the bath is a cataphoresis bath.

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