Anti-roll bar device for a vehicle

Abstract

Anti-roll bar device (20) for a vehicle (10), comprising a first end fixed to a lateral portion (10A) of a chassis of the vehicle (10) and a second end fixed to an opposite lateral portion (10B) of the vehicle chassis (10), the anti-roll bar device (20) comprising: At least one elastic element (23) arranged between the two ends of the anti-roll bar device (20), so as to be able to exert a separation force between the two ends, An adjustable device for prestressing the elastic element (23). Figure 2.

Description

Title of the invention: Anti-roll bar device for a vehicle

[0001] The present invention relates to an anti-roll bar device for a vehicle. The present invention further relates to a method for adapting the road holding of a vehicle.

[0002] The condition of roads or traffic lanes can vary significantly depending on the countries and regions of the world. Thus, the same vehicle may be used primarily in an urban environment on good quality paved roads in a given country or region, but it may be driven on degraded or unpaved roads in another country or region. In addition, a user of a vehicle may use his vehicle both to drive on paved roads and on paths or unpaved roads.

[0003] However, the running gear of a vehicle is generally set once and for all in the factory and is adapted for a certain type of road. This can result in a deterioration in the comfort and / or road holding of the vehicle when it is not used on the type of road for which it was set.

[0004] Document US 10093143 discloses a torsion bar for actively controlling the stability of a vehicle. However, this system is not suitable for adjusting the comfort or handling of a vehicle depending on the type of road on which the vehicle is traveling.

[0005] An aim of the present invention is to overcome these drawbacks and in particular to propose an anti-roll bar device for a vehicle making it possible to adapt the road holding and / or comfort of the vehicle.

[0006] For this purpose, a first aspect of the invention relates to an anti-roll bar device for a vehicle, comprising a first end adapted to be fixed to a lateral portion of a chassis of the vehicle and a second end adapted to be fixed to an opposite lateral portion of the vehicle chassis, the anti-roll bar device further comprising: • At least one elastic element arranged between the two ends of the anti-approach bar device, so as to be able to exert a separation force between the two ends, • An adjustable device for prestressing the elastic element.

[0007] Such an anti-roll bar device makes it possible to adapt the road holding and / or comfort of the vehicle by adjusting the preload of the elastic element and therefore allows adjustment of the rigidity of the chassis of the vehicle according to the road surface or the traffic lane on which the vehicle is traveling or will travel.

[0008] Preferably, an elastic element is provided at each end of the anti-approach bar device. For example, the elastic element may be a steel helical spring.

[0009] Advantageously, the adjustable pre-stressing device or the anti-roll bar device is configured to adopt at least a first configuration in which the elastic element is not pre-stressed and a second configuration in which the elastic element is pre-stressed. Thus, the anti-roll bar device can allow maximum deformation of the vehicle chassis following rolling over bumps or ruts in the first configuration, which is adapted to maximize comfort, particularly when the vehicle is traveling on a roadway comprising a good quality surface.In the second configuration, the anti-roll bar device makes it possible to stiffen the vehicle chassis by limiting or preventing the two side portions of the vehicle from coming together and therefore to optimize road holding, for example when the vehicle is traveling on a bumpy road or one with a degraded surface.

[0010] Advantageously, the adjustable prestressing device or the anti-roll bar device is further configured to adopt a third configuration in which it comprises or defines a connecting assembly arranged to connect the two ends together and having a stiffness greater than a stiffness of the elastic element. For example, the connecting assembly may comprise pistons abutting on interfaces embedded on the lateral portions of the vehicle and defining the ends of the anti-roll bar device, the pistons being subjected to a mechanical and / or hydraulic separation pressure. Thus, the adjustable prestressing device in this third configuration makes it possible to stiffen the chassis of the vehicle by preventing or greatly limiting any coming together between the opposite lateral portions of the vehicle.The vehicle's handling is then optimized, for example, for driving on unpaved roads or off-road.

[0011] Optionally, the elastic element may be placed in a maximum prestress in this third configuration, for example in such a way as to no longer confer elastic properties to the anti-approach bar device. In the case of a helical spring, the turns may be in contact with each other.

[0012] Advantageously, the anti-roll bar device comprises a control unit for the adjustable device for prestressing the elastic element, configured to select a prestress of the elastic element punctually or in real time. Thus, the rigidity of the vehicle chassis can be fa- precisely adapted via this control unit.

[0013] Especially advantageously, the strut bar device comprises a first tube fixed to the first end and a second tube fixed to the second end, the elastic element is fixed to the first end and to the second tube and the strut bar device comprises another elastic element fixed to the second end and to the first tube. Such a strut bar device has a limited space requirement and a high efficiency in modifying the rigidity of the chassis of the vehicle. The tubes are preferably mounted sliding one inside the other and can benefit from surface treatment and / or steel grades adapted to reduce friction or wear and can be fixed at their end to an interface embedded or permanently fixed in a lateral portion of the chassis of the vehicle.

[0014] Advantageously, the adjustable prestressing device comprises at least one piston arranged to prestress the elastic element and preferably one piston per elastic element. The piston may have any suitable shape such as a head adapted to apply a force to the elastic element and optionally a body received in a central space of the elastic element, in particular when it is a helical spring. The piston may be arranged to slide in one of the tubes under the effect of an external force so as to compress the elastic element.

[0015] Advantageously, the adjustable prestressing device comprises an actuator chosen from an electric motor, a hydraulic compressor, a ball screw and a manual wheel arranged to set the piston in motion and to compress the elastic element.

[0016] For example, the actuator is configured to apply no pressure to the piston in the first configuration, limited or intermediate pressure in the second configuration, and maximum pressure in the third configuration of the strut bar device.

[0017] A second aspect of the invention relates to a method for adapting the road holding of a vehicle, the vehicle being provided with an anti-roll bar device according to the first aspect of the invention, in which the preload applied to the elastic element is adapted as a function of a condition of the road surface of the vehicle. This preload can be adapted manually or automatically.

[0018] Advantageously, the prestress applied to the elastic element is adapted as a function of a frequency and / or an amplitude of shocks acquired by a sensor arranged in a ground connection of the vehicle, which makes it possible to adapt in real time the road holding and the comfort of the vehicle to the driving conditions, that is to say to the quality of the road on which the vehicle is traveling.

[0019] A third aspect of the present invention is a motor vehicle comprising an anti-roll bar device according to the first aspect of the invention and / or implementing the method for adapting the road holding of a vehicle according to the second aspect of the invention.

[0020] A fourth aspect of the present invention relates to a computer program comprising program code portions / means / instructions for executing the steps of the method according to the second aspect of the invention when said program is executed on a computer such as the control unit of the anti-roll bar device according to the first aspect of the invention.

[0021] Other characteristics and advantages of the present invention will appear more clearly on reading the following detailed description of embodiments of the invention given by way of non-limiting examples and illustrated by the appended drawing, in which:

[0022] [Fig. 1] shows an anti-approach bar device according to the present invention, in a first configuration.

[0023] [Fig. 2] represents an anti-approach bar device according to Fig. 1, in a second configuration.

[0024] [Fig. 3] represents an anti-approach bar device according to Fig. 1, in a third configuration.

[0025] The present invention relates to an anti-roll bar device 20 for a vehicle and a method for adapting the road holding for any type of land vehicle with three, four or more wheels traveling on traffic lanes or off traffic lanes. It may be an individual or commercial vehicle such as a car or a utility, industrial, collective, agricultural or military vehicle. For example, the vehicle may be a sedan, for example raised, an SUV (Sport and Utility Vehicle) or even an all-terrain vehicle or 4x4.

[0026] With reference to Figure 1, a vehicle 10 comprises a chassis defining two opposite lateral portions 10A and 10B, for example right and left, as well as an engine cradle 11. The engine cradle 11 is arranged to receive a power unit or a portion of this power unit, for example an internal combustion engine and / or an electric motor as well as possibly transmission elements or batteries.

[0027] An anti-roll bar device 20 according to one embodiment may comprise two tubes 21 and 22 concentric and sliding one inside the other. Each tube 21, 22 comprises an end which can be fixed to one of the lateral portions 10A, 10B of the vehicle, for example to an interface 25 fixed on a chassis element or an element of the engine cradle 11, for example at a suspension attachment 12. An elastic element 23, for example in the form of a helical spring licoil, is fixed or positioned in each of the tubes 21, 22 in contact with one of the interfaces 25 so as to exert a separation force between the two ends and therefore between the two lateral portions 10A, 10B.

[0028] Finally, a piston 24 is positioned in each of the tubes so as to be able to compress each elastic element 23. For example, the piston 24 may comprise a head provided with a first surface arranged to receive hydraulic or mechanical pressure and a second surface arranged to be in mechanical connection with the elastic element 23, for example with turns of the coil spring. Furthermore, the piston 24 may comprise a body of smaller diameter or width extending longitudinally from the second surface of the head towards one end of the anti-approach bar device 20 and able to be received in a cavity of the elastic element 23, for example in the central space of the coil spring.

[0029] An actuator 30 such as a hydraulic compressor may be housed in the engine cradle 11 or in the chassis of the vehicle 10 and is connected to the interior space of the two concentric tubes 21 and 22, for example so as to be able to apply or remove hydraulic pressure on the pistons 24 via a fluid stored in the tubes 21, 22. This actuator 30 may be connected to a control unit (not shown) comprising for example a computer circuit responsible for controlling the hydraulic pressure or the force applied by the actuator to the pistons 24. This control unit may be connected to a control interface positioned on the dashboard of the vehicle and / or to one or more shock sensors arranged in the ground connections of the vehicle as in the running gear of the vehicle, for example in a wheel or in a suspension element, in order to select a configuration of the anti-roll bar device 20.

[0030] Thus, the pistons 24 are adapted to apply a prestress to the elastic elements 23 according to several configurations. In a first configuration visible in FIG. 1, the actuator 30 does not apply pressure to the pistons 24 which therefore do not apply a prestress to the elastic elements 23. In this first configuration, the anti-roll bar device 20 according to the present invention has no effect of reinforcing the rigidity of the vehicle 10 and is in some way deactivated. This first configuration can be chosen when the vehicle 10 is traveling on a passable road having a good quality surface, in order to maximize the comfort of the occupants by allowing a certain deformation of the chassis of the vehicle 10.

[0031] In a second configuration visible in Figure 2, the actuator 30 applies pressure to the pistons 24, which in turn apply a prestress to the elastic elements 23. In this second configuration, the anti-roll bar device 20 is active, that is to say it makes it possible to stiffen the chassis of the vehicle. by preventing a movement of approach between the opposite lateral portions 10A, 10B of the vehicle 10, for example following low-amplitude impacts. This second configuration is therefore suitable for use of the vehicle 10 on damaged or dented wheels or for sporty driving of the vehicle 10.

[0032] In this second configuration, the pressure applied by the actuator 30 to the pistons 24 and therefore the prestress applied to the elastic elements 23 can vary continuously, depending for example on the information communicated by the sensor, and the anti-roll bar device 20 is then controlled in real time, depending on the type of road traveled by the vehicle. This information can include one or more frequencies and amplitudes of the shocks to which the sensor or the running gear of the vehicle is subjected. For example, the actuator 30 can work at a frequency of 1 to 100 Hz, preferably 50 Hz.

[0033] In a third configuration visible in Figure 3, the actuator 30 applies maximum pressure to the pistons 24 which come into contact with the interfaces 25, for example at an end surface of the body of each of the pistons 24. The elastic elements no longer confer elastic properties to the anti-approach bar device 20 since the two tubes 21, 22 can no longer slide relative to each other. For example, the elastic elements 23 can be compressed so as to see their turns touching, in particular in the case of helical springs having turns having flat surfaces.

[0034] Thus, the pistons 24 and the pressurized fluid define in this third configuration a connecting assembly between the ends of the anti-roll bar device 20 having a stiffness much greater than the stiffness of the elastic element(s). This connecting assembly can provide great rigidity to the chassis of the vehicle 10 by preventing or greatly limiting any coming together of the opposite lateral portions 10A, 10B. This third configuration is particularly advantageous in the case of driving the vehicle 10 on an unroadworthy road or off-road, in all-terrain driving. Alternatively, this third configuration is also favorable to sporty driving on a circuit, for example in the context of motor racing. In the case of a hydraulic compressor, the hydraulic pressure applied in this third configuration can be at most 10 bars, at most 7 bars or even at most 5 bars.

[0035] The actuator 30 and the pistons 24 therefore constitute an adjustable device for prestressing the elastic elements 23, making it possible to adapt a rigidity provided to the chassis of the vehicle 10. In other embodiments, the actuator 30 comprises one or more electric motors connected to mechanical elements such as racks, manual thumbwheels or even ball screws arranged to apply force to the pistons 24.

[0036] Furthermore, the present invention also relates to a method for adapting the road holding of the vehicle 10 carried out by the present anti-roll bar device 20. In such a method, the prestress applied to the elastic element 23 by the pistons 24 is adapted as a function of a state of the road surface. This prestress can be adapted according to an input from the control interface and / or according to information communicated by the shock sensor, such as information on the frequency and / or amplitude of the shocks, for example according to a vertical displacement of the wheel or of the suspension element.

[0037] To do this, the actuator control unit 30 can be programmed to receive an input from the control interface and / or information from the shock sensor, so as to select the force or pressure applied to the elastic elements 23.

[0038] It will be understood that various modifications and / or improvements obvious to those skilled in the art can be made to the various embodiments of the invention described in the present description without departing from the scope of the invention.

[0039] For example, the actuator 30 may take any form known to those skilled in the art, such as a hydraulic compressor connected to a mechanical or electrical power source of the vehicle 10. In addition, the tubes 21 and 22 may comprise a hydraulic seal allowing their respective sliding movements without leakage of hydraulic fluid. In the embodiment not involving hydraulic fluid or liquid, the tubes 21, 22 may further be omitted or shortened.

[0040] Finally, the elastic elements 30 may comprise any type of element suitable for storing energy when it is deformed and restoring the same quantity when it is released, such as a helical, conical, volute spring or even a diaphragm, blade or gas spring.

Claims

Claims

1. An anti-roll bar device (20) for a vehicle (10), comprising a first end adapted to be fixed to a lateral portion (10A) of a chassis of the vehicle (10) and a second end adapted to be fixed to an opposite lateral portion (10B) of the vehicle chassis (10), the anti-roll bar device (20) further comprising: • At least one elastic element (23) arranged between the two ends of the anti-roll bar device (20), so as to be able to exert a separation force between the two ends, • An adjustable device for prestressing the elastic element (23).

2. Anti-approach bar device (20) according to the preceding claim, characterized in that the adjustable prestressing device is configured to adopt at least a first configuration in which the elastic element (23) is not prestressed and a second configuration in which the elastic element (23) is prestressed.

3. Anti-approach bar device (20) according to the preceding claim, in which the adjustable prestressing device is further configured to adopt a third configuration in which it comprises a connecting assembly arranged to connect the two ends together and having a stiffness greater than a stiffness of the elastic element.

4. Anti-approach bar device (20) according to one of the preceding claims, characterized in that it comprises a control unit for the adjustable device for prestressing the elastic element (23).

5. Anti-approach bar device (20) according to one of the preceding claims, characterized in that it comprises a first tube (21) fixed to the first end and a second tube (22) fixed to the second end, in that the elastic element (23) is fixed to the first end and to the second tube (22) and in that it comprises another elastic element (23) fixed to the second end and to the first tube (21).

6. Anti-approach bar device (20) according to one of the preceding claims, characterized in that the adjustable pre-stressing device comprises at least one piston (24) arranged to pre-stress the elastic element (23).

7. Anti-approach bar device (20) according to the preceding claim, characterized in that the adjustable pre-stressing device comprises an actuator (30) chosen from an electric motor, a hydraulic compressor, a ball screw and a manual wheel arranged to set the piston (24) in motion and to compress the elastic element (23).

8. A method of adapting the road holding of a vehicle (10), the vehicle (10) being provided with an anti-roll bar device (20) according to any one of the preceding claims, wherein the prestress applied to the elastic element (23) is adapted according to a condition of the road surface of the vehicle (10).

9. Method for adapting the road holding of a vehicle (10) according to the preceding claim, in which the prestress applied to the elastic element (23) is adapted as a function of a frequency and / or an amplitude of shocks acquired by a sensor arranged in a ground connection of the vehicle (10).

10. Motor vehicle (10) comprising an anti-roll bar device (20) according to one of claims 1 to 7.

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