Device for height adjustment of a vehicle suspension, and associated control method

Abstract

The invention relates to a device for modifying the length of a vehicle suspension, comprising: - actuation means (113, 117) for modifying said length, and - control means comprising means for detecting the dynamic configuration of the vehicle and means for operating the actuation means (113, 117) based on said detection.

Description

DESCRIPTION TITLE: Device for modifying a vehicle suspension, and associated control method

[0001] The present invention relates to the field of motor vehicles, with two, three or four wheels.

[0002] A motor vehicle is subjected to different dynamic configurations during its movements: stopping, slow speed, fast speed, braking, acceleration, turning...

[0003] These different dynamic configurations are likely to alter the stability and road handling of the vehicle.

[0004] The present invention aims in particular to provide means to improve the stability and road holding of the vehicle when it is in these different dynamic configurations.

[0005] This aim of the invention, as well as other objectives, is achieved with a device for modifying the length of a vehicle suspension, comprising: - means of actuation to modify this length, and - control means including means for detecting the dynamic configuration of the vehicle and means for controlling the actuation means based on this detection, said control means being able to be managed by a mobile application independent of the vehicle system, in which said actuation means are chosen from the group comprising at least one of the following options: - connecting means selected from the group comprising a cable, a chain or a toothed belt, connecting the moving parts of the suspension, and an electric motor capable of winding or unwinding said connecting means, to shorten or lengthen said length of the suspension, - a system comprising compressed air bladders, an air pump to modify the pressure in said bladders and a control system for said pump.

[0006] The term "suspension" used in the context of the present invention refers, as is known in itself, to a vehicle ground connection system comprising on the one hand elastic means (spring...) and on the other hand means for damping the oscillations of these elastic means (hydraulic shock absorber...).

[0007] Such a suspension allows the vehicle to absorb the forces transmitted from the road surface, as well as some of the acceleration components due to braking, acceleration and cornering.

[0008] Modifying the suspension length allows for changes in the vehicle's center of gravity position and / or ground clearance and / or vehicle attitude depending on its dynamic configuration.

[0009] Thus, by appropriately managing this length according to this dynamic configuration, we can improve the vehicle's stability and road handling.

[0010] By shortening the suspension length, you can lower a part of the vehicle (the front or the rear for example) and / or its center of gravity.

[0011] By lengthening this length, we can raise a part of the vehicle (the front or the rear for example), and / or its center of gravity.

[0012] By using a cable, chain, or toothed belt as means of connection between the moving parts of the suspension, and an electric motor capable of varying the length of these means of connection, one obtains actuation means that are compact and can be easily integrated into the structure of an existing vehicle.

[0013] When the system includes compressed air bladders, an air pump and a control system, the following advantages are obtained: - a much more modular solution. The air hoses can be routed more freely around existing vehicle components. The bladders can even be inserted in place of the seat foam, representing a completely different and potentially less intrusive installation method than modifying the suspension itself. This makes the invention applicable to a wider variety of vehicles and installation scenarios; - Since air is a compressible fluid, an air suspension system offers a natural progression (stiffness increases with compression), which can improve comfort and handling. Furthermore, the air pressure can be adjusted very precisely and continuously by the pump, allowing for a potentially wider and more precise range of height and firmness adjustments than a cable system that winds or unwinds; Finally, an air-cooled system can reduce the number of complex and exposed mechanical parts (gears, pulleys, cables) that are subject to wear, corrosion, and require lubrication. A well-designed pump and valves can offer high reliability with less mechanical maintenance.

[0014] When the control system is managed by a mobile application independent of the vehicle's system, the following advantages are obtained: - By separating the control from the vehicle's native electronic system, the invention is no longer dependent on the manufacturer's human-machine interface (instrument cluster, buttons). It can therefore be installed as an aftermarket kit on a very wide range of vehicles, including older or less electronically sophisticated models. The user only needs a smartphone; - A mobile application offers a much richer, more intuitive, and more visual control interface than handlebar buttons. The user can benefit from: precise adjustments via graphic sliders, saving and selecting predefined profiles (e.g., "City", "Highway", "Sport"), display of real-time diagnostic data (pressure, height, etc.), - easy software updates; - The system can operate independently without needing to be connected to the CAN bus or other complex vehicle electronic systems. This greatly simplifies electrical and software installation, reduces costs, and avoids compatibility or warranty issues with the vehicle's original electronics. - The features and control algorithms can be improved and updated via a simple application update, without any hardware intervention on the vehicle. This allows the system to remain efficient and to integrate new features (such as "anti-fall" or "side stand" options) over time.

[0015] The present invention also relates to a vehicle suspension equipped with a device according to the above: such a suspension allows modification of the height of the center of gravity and / or the ground clearance and / or the vehicle's attitude, whether it has two, three or four wheels.

[0016] The present invention also relates to a vehicle comprising at least one suspension conforming to the above: such a vehicle may have a modified ride height according to its dynamic configuration, which makes it possible to increase its stability and road holding.

[0017] The present invention also relates to a method of controlling at least one suspension of the aforementioned vehicle, in which the length of the suspension is adjusted to modify the height of the center of gravity and / or the ground clearance and / or the vehicle's attitude according to the dynamic configuration of the vehicle chosen from the group including stopping, relatively slow speeds, relatively fast speeds, braking, acceleration, turning, detection of an abnormal angle with respect to the vertical axis of the vehicle, or detection of the deployment of a side stand: such a method makes it possible to obtain an active suspension that adapts to the dynamic configuration of the vehicle, and makes it possible to gain stability and road holding.

[0018] The present invention also relates to a method of controlling the front and rear suspensions of a two- or three-wheeled vehicle, in which the length of the suspensions is reduced when the vehicle speed falls below a first predetermined threshold, and this height is increased when the vehicle speed rises above this threshold: in this way the center of gravity of the vehicle can be lowered, and its stability at low speeds increased.

[0019] Depending on other optional characteristics of this process:

[0020] - when the vehicle accelerates, the length of the front suspension is shortened and the length of the rear suspension is lengthened to compensate for the weight shift towards the rear;

[0021] - during vehicle deceleration, the length of the front suspension is lengthened and the length of the rear suspension is shortened to compensate for the effect of deceleration;

[0022] - for a two-wheeled vehicle at rest or at very low speed, when an abnormal angle is detected relative to its vertical axis, maximum compression of the suspensions is commanded to facilitate the vehicle returning to its vertical axis;

[0023] - When the vehicle's side stand is deployed, the suspension length is adjusted to adapt the vehicle's angle to ground conditions and maintain a safe parking angle.

[0024] Other features and advantages of the invention will become apparent from the following description, with reference to the attached figures, which illustrate: [Fig. 1]: a perspective view of the fork and a front wheel of a motorcycle equipped with a front suspension according to the invention; [Fig. 2]: a perspective view of the rear part of a motorcycle and of the rear wheel of this motorcycle equipped with a rear suspension according to the invention; [Fig. 3]: a perspective view of the rear suspension of figure 2, and [Fig. 4]: a perspective view of a variant of this rear suspension, with the spring of this suspension having been removed.

[0025] For clarity, identical or similar elements are identified by identical or similar reference symbols across all figures.

[0026] In what follows, we will describe the invention in the context of a two-wheeled motorcycle, but it is also applicable to a three-wheeled motorcycle, as well as to a four-wheeled motor vehicle (car).

[0027] Referring to Figure 1, we can see the front wheel 1 of a motorcycle, connected to the body of the motorcycle by a fork 3 whose rotation around the axis A allows the motorcyclist to steer his motorcycle.

[0028] This fork 3 incorporates in each of its arms a telescopic suspension 5a, 5b, each typically comprising a cylinder 7 and a piston 9 mounted to slide inside this cylinder 7.

[0029] Hydraulic or mechanical means for damping the forces transmitted by the wheel to the fork are provided in the cylinder 7 of each suspension 5a, 5b.

[0030] On a cross member 11 of the fork which connects the cylinders of the two suspensions 5a, 5b, is fixed an electric motor 13 whose output shaft carries a pulley 15 suitable for winding or unwinding a cable 17 connected to one 9 of the pistons of the two suspensions 5a, 5b.

[0031] Alternatively, this connecting cable 17 can also be replaced by a chain, or by a toothed belt.

[0032] It is also possible to consider that the shaft of the electric motor carries two pulleys, each acting on a cable connected respectively to each of the two pistons 9 of the two suspensions 5a, 5b.

[0033] The electric motor 13 is powered by the motorcycle's battery, and it is controlled by the motorcycle's electronic supervisor (not shown), which is itself connected to a human-machine interface (such as a touchscreen and / or control buttons) allowing the rider to select different operating modes of the suspension assembly described above.

[0034] Alternatively, a control system via an application can be provided to manage settings independently of the existing vehicle system.

[0035] According to one possible operating mode, the motorcyclist can select on the human-machine interface a speed or range of speeds of the motorcycle below which the electric motor 13 starts up to shorten the length of the connecting cable 17, thus having the effect of bringing the pistons 9 of each suspension 5a, 5b inside their respective cylinders 7, and thus lowering the front of the motorcycle: this allows the motorcycle to gain stability at low speeds, and more particularly when stopped - also facilitating the motorcyclist putting his foot down.

[0036] According to another possible operating mode, cumulative or alternative to the previous one, the shortening of the length of the connecting cable 17 can take place when the motorcycle accelerates, in order to compensate for the weight shift towards the rear of the motorcycle under the effect of acceleration.

[0037] It is noted that this acceleration can be detected for example by a gyroscope (not shown) interfaced with the motorcycle's electronic supervisor.

[0038] According to yet another possible mode of operation, alternative or cumulative with the previous ones, the length of the connecting cable 17 can be adjusted actively, that is to say instantaneously according to the accelerations of the motorcycle in the longitudinal (direction of forward movement of the motorcycle), transverse and vertical directions, as represented by the respective axes X, Y and Z of figures 1 and 2.

[0039] These accelerations can be provided by the gyroscope mounted on the motorcycle.

[0040] Such active adjustment allows the position of the center of gravity and the attitude of the motorcycle to be adapted instantly to its different dynamic configurations: stopping, braking, accelerating, turning, passing over rough terrain.

[0041] This can improve the road holding and stability of the motorcycle.

[0042] According to another operating option, known as "anti-fall" of a two-wheeler: at a standstill or at very low speed, the system could detect an abnormal angle relative to the vertical axis of the two wheels and compress the suspensions to the maximum in order to facilitate and reduce the effort of the rider to allow the two-wheeler to be brought back into the vertical axis.

[0043] According to another option, called the side stand option, the system could be coupled to the side stand deployment sensor in order to adapt the angle of the two-wheeler to the ground conditions (slope, holes, bumps, ...) and to maintain the ideal angle for securing the two-wheeler when parking using the side stand, regardless of the terrain configuration (within the possible tolerance to be defined according to the suspensions).

[0044] Note that a tension sensor for the connecting cable 17 can also be provided, located at one end of it or inside the electric motor 13, allowing information representative of the forces transmitted by the front wheel 1 to the fork 3 to be sent to the motorcycle's electronic supervisor.

[0045] This information can be advantageously used by the electronic supervisor to send movement commands to the electric motor 13 to improve the efficiency of the active suspension system - and in particular to better absorb the forces transmitted by the front wheel 1 to the fork 3 when the wheel passes over rough terrain.

[0046] Preferably, but not limitingly, the motorcycle is also provided with a rear suspension according to the invention, as can be seen in figures 2 and 3.

[0047] As can be seen in Figure 3, this rear suspension comprises two flanges 19a, 19b - designated respectively as upper and lower with regard to their positions on the drawing sheet - each equipped with a tab 21a, 21b respectively upper and lower, a spring 23 and a hydraulic shock absorber 25 of the cylinder and piston type being interposed between these two flanges 19a, 19b.

[0048] As can be seen in Figure 2, the upper leg 21a is connected to the structure 27 of the motorcycle, and the lower leg is connected to a movable chassis 28 carrying the rear wheel of the motorcycle.

[0049] As can be seen more particularly in Figure 3, an electric motor 113 is fixed to the upper flange 19a.

[0050] The output shaft of this electric motor 113 can be parallel to the axis of the hydraulic damper 25, as shown in Figure 3, in which case it carries a bevel gear 29 cooperating with a corresponding gear 31 attached to a winding pulley of a connecting cable 117.

[0051] A return pulley 33 fixed on the upper flange 19a opposite the winding pulley allows the connecting cable 117 to be guided to a fixing point 35 located on the lower flange.

[0052] Like the front suspension described above, this rear suspension is linked to the motorcycle's electronic supervisor.

[0053] Thus, the functionalities implemented by the front suspension can also be implemented by the rear suspension, and these functionalities can be coordinated with each other by the motorcycle's electronic supervisor.

[0054] Thus, for example, when the speed of the motorcycle falls below a predetermined speed or speed range, the electric motors 13, 113 of each of the front and rear suspensions can wind the respective connecting cables 17, 117, so as to shorten the lengths of these two suspensions.

[0055] The motorcycle's center of gravity is thus lowered, allowing it to gain stability.

[0056] Thus also, when the motorcycle accelerates, the front electric motor 13 can wind the front link cable 17, while the rear electric motor 113 can unwind the rear link cable 117, allowing optimal weight transfer of the motorcycle to the front, to compensate for the effect of acceleration.

[0057] Conversely, when the motorcycle slows down, the front electric motor 13 can unwind the front link cable 17, while the rear electric motor 113 can wind the rear link cable 117, allowing optimal weight transfer of the motorcycle to the rear, to compensate for the effect of deceleration.

[0058] And when the motorcycle is traveling in a turn and / or on rough terrain, the front 13 and rear 113 electric motors can be continuously controlled by the motorcycle's electronic supervisor in order to instantly adjust its attitude and / or absorb the forces transmitted by the road to the front 1 and rear 28 wheels.

[0059] This results in an active suspension system that reacts instantly to the dynamic conditions of the motorcycle, allowing for improved road holding and stability.

[0060] According to an even more perfected variant of the invention, shown in figure 4, it is also possible to consider that the rear suspension is equipped with a device for modifying the length of the double-acting suspension.

[0061] More specifically, in addition to the first electric motor 113 and its associated connecting cable 117 described above, a second electric motor 213 and a second associated connecting cable 217 are planned.

[0062] This second electric motor 213 is mounted on a lower support 37 attached to the lower flange 19b, and the associated connecting cable 217, passing over a return pulley 233 mounted at the upper end of this lower support 37, is fixed to the lower end 235 of an upper support 237 attached to the upper flange 19a.

[0063] Each of the two electric motors 113, 213 is electrically connected to the motorcycle's electronic supervisor, so that they can be controlled in a coordinated manner to shorten or lengthen the suspension length, depending on the dynamic configurations (stop, brake, accelerate, turn...) in which the motorcycle finds itself.

[0064] It should be noted that in the embodiments of figures 1 to 3, the suspension length modification devices can be mounted on the original suspensions of the motorcycle.

[0065] In contrast, in the embodiment shown in Figure 4, the original rear suspension should be replaced by the one shown.

[0066] According to another embodiment, a system consisting of compressed air bladders can be installed on a two-wheeler, which can be inserted, for example, in place of all or part of the foam composing the saddle, or in series with one or more of the suspensions of the two-wheeler, connected to an air pump and a control system, an installation which could be controlled by an independent mobile application.

[0067] Naturally, the invention described above is by way of example. It is understood that a person skilled in the art is capable of carrying out different embodiments of the invention without departing from its scope.

Claims

DEMANDS 1. Device for modifying the length of a vehicle suspension, comprising: - actuation means (13, 113, 213, 17, 117, 217) to modify this length, and - control means including means for detecting the dynamic configuration of the vehicle and means for controlling the actuation means (13, 113, 213, 17, 117, 217) according to this detection, characterized in that said actuation means are chosen from the group comprising at least one of the following options: - connecting means (17, 117, 217) selected from the group comprising a cable, a chain or a toothed belt, connecting the moving parts of the suspension (7, 9, 19a, 19b), and an electric motor (13, 113, 213) capable of winding or unwinding said connecting means, to shorten or lengthen said length of the suspension; - a system comprising compressed air bladders, an air pump to modify the pressure in said bladders and a control system for said pump.

2. Vehicle suspension equipped with a device according to claim 1.

3. Vehicle comprising at least one suspension according to claim 2.

4. Method of controlling at least one suspension of the vehicle of claim 3, wherein the length of the suspension is adjusted to modify the height of the center of gravity and / or the ground clearance and / or the vehicle's attitude according to the dynamic configuration of the vehicle chosen from the group including stopping, slow speeds, fast speeds, braking, acceleration, turning, detection of an abnormal angle with respect to the vertical axis of the vehicle, or detection of the deployment of a side stand.

5. A method for controlling the front and rear suspensions of a two- or three-wheeled vehicle according to claim 4, wherein the length of the suspensions is reduced when the vehicle speed falls below a predetermined threshold, and this height is increased when the vehicle speed rises above this threshold.

6. A method for controlling the front and rear suspensions of a two- or three-wheeled vehicle according to claim 4, wherein, during acceleration of the vehicle, the length of the front suspension is shortened and the length of the rear suspension is lengthened to compensate for the weight transfer to the rear.

7. A method for controlling the front and rear suspensions of a two- or three-wheeled vehicle according to claim 4, wherein, during deceleration of the vehicle, the length of the front suspension is lengthened and the length of the rear suspension is shortened to compensate for the effect of the deceleration.

8. Control method according to claim 4, wherein, for a two-wheeled vehicle at rest or at very low speed, upon detection of an abnormal angle with respect to its vertical axis, maximum compression of the suspensions is commanded to facilitate the return of the vehicle to its vertical axis.

9. Control method according to claim 4, wherein, upon detection of the deployment of the vehicle's side stand, the suspension length is adjusted to adapt the vehicle's angle to ground conditions and maintain a secure parking angle.

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