FR3059628A1 - SYSTEM FOR VARIATION OF TRAINING AND MOTOR VEHICLE COMPRISING SUCH A SYSTEM - Google Patents

Abstract

The invention relates to a system (1) for variation of drag for a motor vehicle comprising an extensible device (3) provided with passive aerodynamic means (13) using the flow of air on the system (1) of variation of drag to activate the extensible device (3).

Description

© Publication no .: 3,059,628 (to be used only for reproduction orders)

©) National registration number: 16 61870 ® FRENCH REPUBLIC

NATIONAL INSTITUTE OF INDUSTRIAL PROPERTY

COURBEVOIE

©) Int Cl ⁸ : B 62 D 37/02 (2017.01), B 62 D 35/00

A1 PATENT APPLICATION

(22) Date of filing: 02.12.16. © Applicant (s): COMPAGNIE PLASTIC OMNIUM (30) Priority: Public limited company - FR. ©) Inventor (s): LETERRIER FRANCK. ©) Date of public availability of the request: 08.06.18 Bulletin 18/23. (56) List of documents cited in the report preliminary research: Refer to end of present booklet (© References to other national documents ©) Holder (s): COMPAGNIE PLASTIC OMNIUM related: Anonimous society. ©) Extension request (s): ©) Agent (s): LLR.

194 / TRAILER VARIATION SYSTEM AND MOTOR VEHICLE COMPRISING SUCH A SYSTEM.

The invention relates to a drag variation system (1) for a motor vehicle comprising an expandable device (3) provided with passive aerodynamic means (13) using the flow of air on the variation system (1) drag to activate the extendable device (3).

FR 3 059 628 - A1

305962S

-1 The invention relates to a drag variation system for a motor vehicle. It is already known to form active rear fins according to the speed of the motor vehicle in order to modify the downforce in particular above 90 km.h ′ ¹ . These fins, generally formed by a rigid blade, are moved using at least one electric motor in order to give an incidence capable of generating maximum grip and traction in the vehicle.

However, these fins are very heavy, in particular because of the electromechanical actuators controlled and the deployment mechanisms with respect to a fixed fin, which increases the cost and the mass of the motor vehicle on which it is mounted.

The object of the invention is to remedy these drawbacks by providing a drag variation system for a passive type motor vehicle making it possible to limit its impact on the mass of the vehicle.

To this end, the invention relates to a drag variation system for a motor vehicle comprising an extendable device and a fixing device arranged to secure said system on a motor vehicle, characterized in that the extendable device comprises aerodynamic means passive using the air flow on the drag variation system to activate the expandable device.

Advantageously according to the invention, the system is of the passive type, that is to say it uses the movement of the vehicle and in particular the natural flow of air around the vehicle to deploy. Thus, the installation is easier both from the point of view of the volume required and of the added mass, in particular compared to active systems such as, for example, a movable fin cited above. The system works autonomously for the user of the vehicle, that is to say it has no manipulation to carry out.

According to other optional features for carrying out the invention:

- The fixing device comprises a frame supporting the extensible device;

- The expandable device comprises at least one envelope that can be extended relative to the fixing device and moved by passive aerodynamic means;

- The expandable device comprises several envelopes that can be extended telescopically;

- the passive aerodynamic means comprise at least one elastic membrane collecting said air flow in order to selectively vary its volume to actuate the expandable device;

- The volume of said at least one elastic membrane increases with the increase in the flow of air to actuate the expandable device;

- Said at least one elastic membrane is formed of elastomer;

- the system also includes a passive recall device for the expandable device

-2 allowing in the absence of air flow on the drag variation system to fold the expandable device;

- the passive return device comprises a spring mounted between the extendable device and the fixing device in order to fold the extendable device in the absence of air flow on the drag variation system.

Finally, the invention relates to a motor vehicle characterized in that it comprises at least one drag variation system as presented above. Preferably, said at least one system is attached to the roof or the tailgate of said motor vehicle.

We will now present embodiments of the invention given by way of nonlimiting examples and with the support of the appended figures in which:

- Figure 1 is a perspective representation of a first embodiment of a drag variation system according to the invention;

- Figure 2 is a sectional representation along the plane II-II of Figure 1;

- Figure 3 is a perspective representation of a second embodiment of a drag variation system according to the invention in the deployed position;

- Figure 4A is a sectional representation along the plane IV-IV of Figure 3;

- Figure 4B is a sectional representation similar to Figure 4A, the drag variation system according to the invention being in the retracted position;

- Figure 5A is a sectional representation along the plane V-V of Figure 3;

- Figure 5B is a sectional representation similar to Figure 5A, the drag variation system according to the invention being in the retracted position;

- Figure 6 is a partial representation of a first variant of the drag variation system according to the invention;

- Figure 7 is a partial representation of a second variant of the drag variation system according to the invention.

In the various figures, identical or similar elements have the same references. The description of their structure and their function is therefore not systematically repeated.

As illustrated in FIGS. 1 and 2, the invention, according to a first embodiment, relates to a system 1 for varying the drag for a motor vehicle 2, that is to say a system intended to reduce the resistance of the air when moving the motor vehicle to gain speed and / or to save energy. Preferably, system 1 forms an air deflector located at the level of the roof or tailgate of the motor vehicle. This air deflector can thus be a spoiler on the roof, a spoiler on the tailgate or a side deflector on the tailgate, integrated in the

- 3 side uprights located on each side of the telescope.

In the example of the first embodiment, the drag variation system 1 is intended to be mounted on the rear upper part of a roof 4 of a motor vehicle 2. As better visible in FIG. 2, the system 1 is integrated to form a spoiler 9 at the level of the roof 4 or the tailgate 12 of the vehicle 2.

The system 1 comprises an extendable device 3 deployed, preferably, from a predetermined speed of the vehicle on which it is integrated. Preferably, the extensible device 3 comprises a chassis 5 and an extensible casing 7 intended to extend rearward the surface of the spoiler 9 of the vehicle 2 along which the air flows. It is understood that the envelope 7 deployed makes it possible to reduce the drag of the vehicle 2. The term envelope describes a hollow rigid part in order to limit the overall mass of the system 1 but also to receive therein at least part of the passive aerodynamic means 13. For these same considerations, the chassis 5 and the extensible casing 7 can be made from plastic material preferably obtained by an injection molding process.

The drag variation system 1 also comprises a fixing device 10 designed to integrate the spoiler 9 on a motor vehicle. Preferably, the fixing device 10 comprises a frame 11 supporting the extensible device 3. The frame 11 thus guarantees a fixed interface between the extensible device 3 and the roof 4 or the tailgate 12 of the vehicle 2.

As can be seen in FIG. 1, the frame 11 has two grooves 15 intended to direct part of the air flow towards the passive aerodynamic means 13. More specifically, the grooves 15 open out towards a channel 17 facing the extendable device 3 and more particularly to the chassis 5. Finally, it is noted that the channel 17 may or may not be open towards the bezel 6 in order to form an exhaust to the air flow deflected by the grooves 15. Of course, the number of grooves 15 can change according to the passive aerodynamic means 13 used. For example, a single groove 15 could cover most of the width of the spoiler 9 or a number greater than two could be provided to correspond to that of the passive aerodynamic means 13.

Preferably, the extensible device 3 is arranged to be deployed from a predetermined speed corresponding to a drag and a significant overconsumption for the vehicle 2. For example, the extensible device 3 could be arranged to begin to deploy at 50 km.h ' ¹ to be fully deployed in direction A only from 90 km.h' ¹ .

Advantageously according to the invention, the extensible device 3 comprises passive aerodynamic means 13 using the flow of air along the variation system 1

- 4 drag to activate the extendable device 3. Thus, the system 1 is of the passive type, that is to say it uses the speed of movement of the vehicle 2 and, more precisely, the flow of air along the roof 4 or the tailgate 12 induced by moving the vehicle 2, to selectively deploy or retract. It is therefore understood that no energy on board or produced by the motor vehicle 2 is necessary to activate the expandable device 3. In addition, installation is easier both from the point of view of the volume required and of the added mass, in particular compared to controlled electromechanical systems.

As illustrated in FIG. 2, the passive aerodynamic means 13 comprise at least one deformable or elastic membrane 19, preferably made of elastomer, collecting the flow of air which arrives from the channel 17 in order to vary its volume and that its wall exerts thus a thrust against the internal walls of the envelope 7 to move it towards the rear of the motor vehicle 2. In the example of FIG. 2, a membrane 19 is shown with a maximum variation in its volume corresponding to the maximum displacement between the chassis 5 and the casing 7. The same membrane referenced 19 'has also been shown at rest for a better understanding.

In addition, in order to promote the most laminar possible air flow but also to improve the aesthetics of the drag variation system 1, it is visible in FIGS. 1 and 2 that a deflector 21, possibly having become deformed, for example by molding, with the chassis 5, is positioned at the interface between the chassis 5 and the casing 7.

Preferably, the system 1 also comprises a device 23 for passive return of the extensible device 3. Indeed, it is preferably desired that in the absence of sufficient air flow, that is to say below the predetermined speed of the vehicle 2, or that when the vehicle 2 stops , the expandable device 3 is fully returned to the rest position, that is to say that the casing 7 retracts as far as possible into the chassis 5.

As can be seen in FIG. 2, the passive return device 23 comprises, for example, at least one spring 25 of the helical type mounted between the frame 5 and the end of the casing 7 in order to fold the device 3 extendable therein. absence of air flow on the system 1 of variation of drag. The stiffness of the spring 25 must be selectively chosen to allow the deployment of the casing 7 but must also allow its reentry during the deceleration phase then the stopping of the vehicle 2.

Finally, the frame 5 can also include a pivoting hatch 27 allowing the entry of air into the membrane 19 from a predetermined flow rate and / or retaining the air present to limit the time when the envelope 7 can move.

A second embodiment of a system 1 according to the invention is presented to

- 5figures 3 to 5B. This second embodiment is essentially distinguished from the first embodiment by the fact that the extendable device 3 comprises several envelopes 7 _{X which are} preferably extendable telescopically.

As can be seen in FIG. 3, the extensible device 3 comprises a chassis 5 and two extensible envelopes 7i, 7 ₂ intended to extend rearward the surface of the spoiler 9 of the vehicle 2 along which the air flows. It is understood that the envelopes 7i, 7 ₂ deployed make it possible to reduce the drag of the vehicle 2.

In addition, it can be seen in FIGS. 3 to 5B that a deflector 211, 21 ₂ , possibly made of one piece with respectively the chassis 5 and the casing 7 ₂ , is positioned at each interface respectively between the chassis 5 and the casing 7 ₂ or between the envelopes 7i and 7 _{2 in} order to promote the most laminar air flow possible but also improve the aesthetics of the system 1 of variation of drag.

According to the second embodiment of the invention, the passive aerodynamic means 13 comprise at least one deformable or elastic membrane 19, preferably made of elastomer, collecting the flow of air arriving from the channel 17 in order to vary its volume and that its wall thus exerts a thrust against the internal walls of the two envelopes 7i, 7 ₂ . to move them towards the rear of the motor vehicle 2. By comparing FIGS. 4A-5A and 4B-5B showing the device 3 extendable respectively in its deployed and retracted position, we can better see the variation in the volume of the membrane 19 between FIG. 4A representing its maximum variation and, FIG. 4B, its minimum variation.

As for the first embodiment, the system 1 of the second embodiment may further comprise a device 23 for passive return of the extensible device 3 comprising, for example, at least one spring 25 of the helical type mounted between the chassis 5 and the 'end of the envelope 7i in order to fold the device 3 expandable in the absence of air flow on the system 1 of variation of drag, that is to say go from Figures 5A to Figure 5B.

The stiffness of said at least one spring 25 must be selectively chosen to allow the deployment of the envelopes 7i, 7 ₂ but must also allow their reentry during the deceleration and stopping phase of the vehicle 2. For example, springs 25 with different stiffnesses could be respectively attached to the envelopes 7i, 7 _{2 in} order to program a predetermined deployment of the envelopes 7i, 7 ₂ . By way of example, the extensible device 3 could be arranged to begin to deploy, at 50 km.h ' ¹ , the envelope 7 _{2 so as} to be fully deployed only from 70 km.h' ¹ . At this same last speed, the extensible device 3 could begin to deploy the envelope 7i in order to be fully deployed only from 90 km.h ′ ¹ .

Finally, the frame 5 can also include a pivoting hatch 27 allowing

- 6the entry of air into the membrane 19 from a predetermined flow rate and / or retaining the air present to limit the time when the envelopes 7ι, I2 can move.

The invention is not limited to the embodiments presented and other embodiments will be apparent to those skilled in the art. It is in particular possible that several drag variation systems 1 are attached to the same vehicle 2 or that the system 1 is not mounted on the roof 4 but, alternatively, on the tailgate 6 or another part of the body of the vehicle 2.

The geometry of system 1 cannot be limited to those presented in FIGS. 1 to 5B. It is in particular immediate that the extendable devices 3 presented below employ a kinematics whose direction is substantially parallel to the pavilion 4. However, the kinematics and / or the shape of the envelopes 7, 7 _X could be modified in order to increase the downforce of the vehicle by offering a direction of deployment oblique to the upper surface of the roof 4.

As illustrated in FIG. 6, it is also possible that several membranes 19i,

192, 193, 194, 19δ are used. The number of envelopes will be calculated as a function of the effort necessary for the deployment of the envelopes 7, 7 _X but will also, if necessary, have to overcome the stiffness of the springs 25.

Finally, the membrane 19 is presented in FIGS. 2 and 4A according to its maximum volume for which the membrane 19 is pressed against the chassis 5 and the casing 7,

7 _X. In fact, this configuration avoids, from a certain air flow, no longer being able to inflate the membrane 19 more in order to avoid any tearing.

As shown in FIG. 7, alternatively, at least one hole 20 in the membrane 19 could be provided in order to create a leakage rate B capable of capping the maximum volume attainable by the membrane 19 in order to avoid any tearing.

Claims (11)

1. Drag variation system (1) for a motor vehicle comprising an extendable device (3) and a fixing device (10) arranged to secure said system to a motor vehicle (2), characterized in that the device (3 ) extendable comprises passive aerodynamic means (13) using the flow of air over the drag variation system (1) in order to activate the extendable device (3). 2. System (1) according to the preceding claim, in which the fixing device (10) comprises a frame (11) supporting the extensible device (3). 3. System (1) according to any one of the preceding claims, in which the extendable device (3) comprises at least one envelope (7, 7i, IA extendable relative to the fixing device (10) and moved by the means ( 13) passive aerodynamics. 4. System (1) according to the preceding claim, wherein the expandable device (3) comprises several envelopes (7, 7i, IA telescopically expandable. 5. System (1) according to any one of the preceding claims, in which the passive aerodynamic means (13) comprise at least one elastic membrane (19) collecting said air flow in order to selectively vary its volume in order to actuate the expandable device (3). 6. System (1) according to the preceding claim, wherein the volume of said at least one elastic membrane (19) increases with the increase in the flow of air to actuate the device (3) expandable. 7. System (1) according to claim 5 or 6, wherein said at least one elastic membrane (19) is formed of elastomer. 8. System (1) according to any one of the preceding claims, in which the system (1) further comprises a device (23) for passive return of the extendable device (3) allowing in the absence of air flow on the drag variation system (1) to fold the extendable device (3). 9. System (1) according to the preceding claim, wherein the device (23) passive return comprises a spring (25) mounted between the device (3) extendable and the device (10) for fixing in order to fold the device (3 ) expandable in the absence of air flow on the drag variation system (1). 10. Motor vehicle (2) characterized in that it comprises at least one variation system (1) of drag according to one of the preceding claims. 11. Motor vehicle (2) according to the preceding claim, wherein said at least one system (1) is attached to the roof (4) or to the tailgate (6) of said motor vehicle. - 83059628 1/4