Suspension system for three-wheeled or multi-wheeled vehicles that can be tilted and steered during continuous drive

Abstract

A suspension system tiltable and steerable upon continuous drive for a vehicle comprising a chassis and three or more wheels, with at least first and second wheels arranged on laterally opposed sides of the vehicle. The system comprises: at least first and second support arms, the inner ends of which are hinged to the chassis and the outer ends of which rotatably support a first support element of a first wheel and a second support element of a second wheel, respectively, about a steering axis; the outer ends of the second arms are hinged to the first supporting element and the second supporting element respectively, and the inner ends of the second arms are hinged to each other; the first end of the shock absorber is hinged to the chassis; the inner ends of the connecting rods are hinged to each other and hinged to the second end, opposite to the first end, of the shock absorber, and the outer ends of the connecting rods are hinged to a part of the first supporting arm and a part of the second supporting arm respectively. And at least one abutment element configured to abut the first or second support arm to prevent the possibility of rotation of the hinge restraint about the respective inner end beyond a predetermined rotation angle associated with the first tilt angle of the vehicle.

Description

Technical Field

[0001] The present invention relates to a suspension system that can be tilted and steered during continuous driving, which is particularly suitable for three-wheeled or multi-wheeled vehicles. In particular, the present invention relates to a motorcycle with at least three wheels, two of which are side by side and can be tilted laterally due to the presence of a connection system between the two side by side wheels. Background Art

[0002] The type of vehicle in question is a vehicle with three or more wheels, such as motorcycles and scooters, in which two wheels (according to the best known embodiment, the two front wheels) are aligned on an axis and oscillate by means of a mechanical or oil-hydraulic oscillation system. These vehicles have a steerable suspension system connecting the pairs of wheels, allowing the vehicle itself to tilt relative to the ground. In fact, the three-wheeled or multi-wheeled motorcycle in question has the characteristic of being able to tilt laterally to a certain angle towards the inside of a turn when traveling, exactly like a two-wheeled vehicle (such as a motorcycle of the conventional type).

[0003] This function is provided by a tilt or swing mechanism, which usually consists of a system of levers connecting the hubs of a pair of wheels on the same axis, which allows the wheel on one side to move upward relative to the vehicle and the wheel on the other side to move downward relative to the vehicle accordingly.

[0004] These mechanisms also include one or more shock absorbers consisting of springs and dampers to absorb ground irregularities and control the transfer of longitudinal loads throughout the vehicle.

[0005] In the prior art, the connection system between two side-by-side wheels is of the mechanical type with longitudinal or transverse arms of various solutions known in the field of automobile or motorcycle design. In particular, a first mechanism guides the vertical movement of the two wheels, a second mechanism couples the right wheel to the left wheel so that a downward movement of one wheel corresponds to an equal upward movement of the opposite wheel, a third mechanism connects the two wheels to shock absorbers and a fourth mechanism (in the case of the front wheels) allows steering to guide the vehicle.

[0006] However, these known swing systems are not without disadvantages or limitations, among which should be included that they do not allow a progressive and continuous descending movement when turning, ie a change in the inclination of the vehicle, which would therefore provide the rider with greater safety than riding a simple two-wheeled motorcycle.

[0007] Another drawback of these known types of oscillating systems is the excessive weight compared to a two-wheeled motorcycle or scooter with the same characteristics, which is particularly pronounced during maneuvers starting from rest, when the rider must keep the vehicle in an upright position, or after losing control of the vehicle's upright state he must return the vehicle to an upright position.

[0008] Another disadvantage of such oscillating systems of known type is that they are generally not easily adjustable to the needs of the cyclist, whether professional or beginner.

[0009] It is therefore obvious that the heavier a three-wheeled or multi-wheeled vehicle is, the more effort a rider must exert to move such a vehicle from rest so that it leans to the right or left relative to the vertical, compared to a conventional vehicle. Summary of the invention

[0010] In view of the above, the task of the present invention is to realize a tilt-steerable suspension system, in particular for three-wheeled or multi-wheeled vehicles, which overcomes the limitations of the prior art and allows a more natural and safer continuous driving and lowering of the vehicle when turning.

[0011] Within the scope of this task, an object of the invention is to realize a tiltable steerable suspension system which allows the rider to more easily bring the vehicle into an upright position when the vehicle is in a tilted position, for example when the vehicle is moving from a standstill and when the vehicle is driving along a bend.

[0012] Another object of the invention is to obtain a vehicle that is safer, easier to drive and manage both when starting from rest and when in motion, since it has a tilt-steerable suspension system that allows limiting the forces required to return the vehicle to an upright position starting from a tilted position.

[0013] Another object of the present invention is to realize a tilt-steerable suspension system which can provide the widest range of reliability and safety guarantees in use.

[0014] Another object of the invention is to achieve a tilt-steerable suspension system that is able to adapt to the riding style of experienced cyclists and to the riding style of beginners, thanks to the possibility of modifying the vehicle's sustenance values.

[0015] Another object of the present invention is to realize a tilt-steerable suspension system which is easy to realize and economically competitive compared to the prior art.

[0016] The above tasks and the stated aims and other aims which will emerge better below are achieved by a suspension system which is tiltable and steerable during continuous driving according to claim 1 and a three-wheeled or multi-wheeled vehicle according to claim 7 .

[0017] Further features are provided in the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Further features and advantages of the present invention will become more apparent from the illustrative but non-limiting description of preferred embodiments of the invention illustrated with the aid of the accompanying drawings, in which:

[0019] Figure 1 is a perspective view of the front portion of a three-wheeled vehicle according to the present invention, the vehicle including a suspension system that can tilt and steer during continuous driving;

[0020] Figure 2 yes Figure 1 Another perspective view of the portion of the vehicle shown, but with the two front wheels partially removed;

[0021] Figure 3 is a bottom perspective view of a suspension system that can tilt and steer during continuous driving according to the present invention;

[0022] Figure 4 is another bottom perspective view of a suspension system that can tilt and steer during continuous driving according to the present invention;

[0023] Figure 5 is a front view of a suspension system in an upright position that can tilt and steer during continuous driving according to the present invention;

[0024] Figure 6 , Figure 6a and Figure 6b is a front view of a suspension system that can tilt and steer during continuous driving according to the present invention, the system tilting according to a first tilt angle, and is shown without wheels, with wheels, and without wheels or chassis respectively;

[0025] Figure 7 and Figure 7a is a front view of a suspension system that is tiltable and steerable during continuous driving according to the present invention, the system tilting according to a second tilt angle, and is shown with and without wheels respectively;

[0026] Figure 8 and Figure 8a is a front view of a suspension system that can tilt and steer during continuous driving according to the present invention, the system tilting according to a maximum tilt angle, and is shown with and without wheels respectively;

[0027] Fig. 9 is a perspective view of a portion of a suspension system that can tilt and steer during continuous driving according to the present invention;

[0028] Fig.10 and Fig.10a yes Fig. 9 Front views of two different variations of the suspension system portion shown. DETAILED DESCRIPTION

[0029] With particular reference to the drawings, a suspension system that can tilt and steer during continuous driving is generally indicated by reference numeral 1. Such a system 1 is suitable for a vehicle 2 comprising a chassis 23 and three or more wheels, wherein at least a first wheel 21 and a second wheel 22 are respectively arranged on opposite sides of the vehicle 2 itself.

[0030] The vehicle 2 can be, for example, a swinging three-wheeled vehicle with an endothermic engine and electric motorization. Alternatively, the vehicle 2 can also be a four-wheeled vehicle, always swinging.

[0031] The two wheels 21 and 22 located on the side of the vehicle 2 may also be offset from one another.

[0032] According to the embodiment shown in the figures, the vehicle 2 is a three-wheeled vehicle, in which the steerable and swiveling wheels are two front wheels 21 and 22, which are coupled to the same axle (front axle).

[0033] According to the present invention, the tiltable and steerable suspension system comprises at least a first support arm 31, 33 and at least a second support arm 32, 34, which are adapted to be hinged to the chassis 23 at their respective inner ends (generally indicated by 35), and adapted to rotatably support a first support element 41 of the first wheel 21 and a second support element 42 of the second wheel 22 at their respective outer ends around steering axes S41, S42, respectively.

[0034] The terms “inside” and “outside” should be understood with respect to the vehicle 2 as follows: “inside” means a direction toward the center of the vehicle 2 , and “outside” means a direction toward the side of the vehicle 2 .

[0035] The system 1 comprises at least one pair of tie rods 51, 52, 53, 54, which are hinged at their outer ends (generally indicated at 55 and 56) to the first support element 41 and the second support element 42, respectively.

[0036] The tie rods 51 , 52 , 53 , 54 are also hinged to each other at the inner ends 57 .

[0037] The system 1 also comprises a shock absorber 7 which is hinged to the chassis 23 at a first end 70 .

[0038] The system 1 further comprises a pair of connecting rods 81, 82 which are hinged to each other at the inner ends and to the second end 71 of the shock absorber 7 opposite to the aforementioned first end 70. The connecting rods 81, 82 of the pair of connecting rods are then hinged at the outer ends to a part of the first support arm 31, 33 and a part of the second support arm 32, 34, respectively.

[0039] The system 1 also includes at least one abutment element 91, 92, which is configured to abut the first support arm 31, 33 or the second support arm 32, 34, respectively, thereby preventing the possibility of rotation around the respective hinge restraints C31, C32 present in the respective inner ends 35 exceeding a predetermined rotation angle associated with the first tilt angle of the vehicle 2.

[0040] Essentially, especially by comparing Figure 5 and Figure 6 It is clearly seen that when the vehicle 2 is tilted relative to the vertical direction, the first support arm 31, 33 and the second support arm 32, 34 can rotate freely around their respective hinge constraints C31, C32 until the vehicle 2 reaches a first tilt angle α, at which the first support arm 31, 33 or the second support arm 32, 34 (depending on the tilting side) abuts against the abutment elements 91, 92.

[0041] In fact, as better explained below, within this first inclination angle α, neither in motion from a stationary state nor in dynamic driving, the vehicle 2 requires a verticalization effect, since it is a small or medium inclination angle. Thus, from a stationary state, the cyclist can return the vehicle 2 to an upright position with a small or medium effort, and in dynamic driving, having this type of verticalization effect is not particularly useful.

[0042] Preferably, as shown in the drawings, there are two pairs of support arms 31, 32 and 33, 34 arranged parallel to each other.

[0043] Preferably, as shown in the drawings, the system 1 comprises a first bracket 45 and a second bracket 46 respectively hinged to the first support element 41 and the second support element 42. Tie rods 51, 52, 53, 54 are hinged at their outer ends 55 and 56 to the first bracket 45 and the second bracket 46 respectively.

[0044] Preferably, the system 1 comprises two pairs of tie rods 51 , 52 and 53 , 54 , two by two parallel, articulated at their respective outer ends 55 , 56 to the support elements 41 , 42 of the two wheels 21 , 22 , for example by means of identical brackets 45 , 46 .

[0045] Preferably, the ties 51 , 52 , 53 , 54 are articulated to one another at the respective inner ends 57 by means of a common articulation element C58 and / or by means of a common articulation element C5 obtained in a swing support 59 associated with the chassis 23 .

[0046] Preferably, the connecting rods 81 , 82 are hinged to each other at their inner ends by a common hinge element C83 and to the second end 71 of the shock absorber 7 .

[0047] Preferably, the shock absorber 7 is configured to compress only when the vehicle 2 is inclined at an angle of inclination greater than a first angle of inclination (α) associated with said predetermined angle of rotation.

[0048] Preferably, the system 1 comprises a pair of elastic end stop elements 110, 111 designed to abut respective elements of the feedback system 1 (which may for example be constituted by two tie rods 51, 52, 53, 54) when the vehicle 2 is tilted at a maximum tilt angle β greater than the first tilt angle α.

[0049] exist Figure 6 , Figure 6a , Figure 6b , the system 1 is shown in an inclined configuration at a first inclination angle α.

[0050] exist Figure 8 , Figure 8a , the system 1 is shown in an inclined configuration with a maximum inclination angle β.

[0051] exist Figure 7 , Figure 7a , the system 1 is shown in a tilted configuration at a second angle comprised between the first tilt angle α and the maximum tilt angle β.

[0052] When the vehicle 2 is at an inclination angle between the upright position and the first inclination angle α, the first support arms 31, 33 and the second support arms 32, 34 are free to rotate until one of the support arms rests on the abutment elements 91, 92. Within this first inclination angle α, the vehicle 2 is statically and dynamically comparable to a normal two-wheeled motorcycle or scooter, with the advantage that the extra wheel at the front ensures safe braking and cornering.

[0053] When the vehicle 2 is at the maximum tilt angle β, at least one element of the system 1 , for example one of the tie rods 51 , 52 , 53 , 54 , for example rests with its outer end 56 , 57 on one of the two elastic end stop elements 110 , 111 .

[0054] The verticalization effect of the invention is achieved between the first inclination angle α and the maximum inclination angle β. This effect is explained by the fact that, in order for the vehicle 2 to reach the inclination angle β from the inclination angle α, the shock absorber 7 must be compressed by a kinematic effect, thereby storing energy released during the step of decreasing the inclination angle, i.e. when the vehicle reaches the angle α from the angle β (or in any case starting from an angle greater than the first inclination angle α).

[0055] Preferably, the at least one abutment element 91, 92 comprises a pair of abutment elements, and the first support arm 31, 33 or the second support arm 32, 34 can abut against the outer surface 910, 920 of the abutment element. In particular, as shown in the drawings, the first abutment element 91 serves as an abutment portion of the first support arm 31, 33, and the second abutment element 92 serves as an abutment portion of the second support arm 32, 34.

[0056] Preferably, there may be two pairs of abutment elements, one for each support arm, in the case where the system 1 has a pair of support arms 31,32 and 33,34. Advantageously, the support arms indicated with 31,33 are integral as are the support arms 32,34.

[0057] Preferably, the abutment elements 91 , 92 may comprise rubber pads.

[0058] Preferably, the aforementioned pair of abutment elements 91, 92 may be selected from a group comprising at least two pairs of abutment elements, wherein a total occupied area of ​​abutment elements in a first pair of abutment elements is different from a total occupied area of ​​abutment elements in a second pair of abutment elements.

[0059] By choosing different pairs of abutment elements with different total occupied areas, it is in fact possible to increase or decrease the angle of rotation allowed by the first support arm 31, 33 or the second support arm 32, 34 before hitting one of the two abutment elements, and therefore it is possible to choose different values ​​for the first tilting angle α, beyond which the intervention of the shock absorber 7 takes over.

[0060] Preferably, the pair of abutment elements 91, 92 are made of elastic material and can be selected from a group including at least two pairs of abutment elements, wherein the elastic coefficient of the elastic material of the abutment elements in the first pair of abutment elements is different from the elastic coefficient of the material of the abutment elements in the second pair of abutment elements.

[0061] Preferably, the abutment elements 91, 92 are cylinders, so that a pair of cylinders 91, 92 can be selected from a group comprising at least two pairs of cylinders, wherein the base circle diameter of the cylinders in the first pair of cylinders is different from the base circle diameter of the cylinders in the second pair of cylinders in the length.

[0062] By choosing different pairs of cylinders with different diameters, it is in fact possible to increase or decrease the angle of rotation allowed by the first support arm 31, 33 or the second support arm 32, 34 before hitting one of the two cylinders, and therefore it is possible to choose different values ​​for the first tilt angle α, beyond which the intervention of the shock absorber 7 takes over.

[0063] Preferably, the pair of cylinders 91, 92 is made of elastic material and can be selected from the group consisting of at least two pairs of cylinders, wherein the elastic coefficient of the elastic material of the cylinders in the first pair of cylinders is different from the elastic coefficient of the material of the cylinders in the second pair of cylinders.

[0064] In this way, the response of the vehicle 2 can also be modified when a first tilt angle α is reached, beyond which the intervention of the shock absorber 7 takes over.

[0065] The cylinder of resilient material may be positioned differently in the area of ​​abutment with the arms 31, 33 and 32, 34, for example at the front rather than at the rear, as shown.

[0066] The support arms 31 , 32 and 33 , 34 and the tie rods 51 , 52 and 53 , 54 define an articulated parallelogram which defines a so-called “parallelogram of the suspension”.

[0067] The support elements 41 , 42 of the wheels 21 , 22 comprise, in a manner known per se, the hubs of the wheels 21 , 21 and the disc brake pads of the brake system.

[0068] The figures also show a steering column 120 and steering tie rods 121 , 122 of the system 1 . In the upper part, the steering column 120 engages a handlebar 123 of the vehicle 2 .

[0069] Preferably, if Fig. 9 , Fig.10 , Fig.10a As shown, the connecting rods 81, 82 are hinged to the central parts of the first supporting arms 31, 33 and the second supporting arms 32, 34 at points indicated by C81 and C82, respectively.

[0070] Preferably, the connecting rods 81, 82 have an arc shape passing through hinge centers C81, C82 with the support arms 31, 33 and 32, 34, and the inner ends of the connecting rods 81, 82 themselves and the second end 71 of the shock absorber 7 are hinged to the hinge center C83.

[0071] The present invention also relates to a vehicle 2 comprising a chassis 23 and three or more wheels, wherein at least a first wheel 21 and a second wheel 22 are respectively arranged on opposite sides of the vehicle 2, and also comprises a suspension system 1 as described above which can be tilted and steered during continuous driving.

[0072] In practice, it has been found that the suspension system according to the invention, in particular for three-wheeled or multi-wheeled vehicles, tiltable and steerable during continuous driving, achieves the task and the intended purpose, since it allows the rider to more easily bring the vehicle to an upright position when the vehicle is in a tilted position, either starting from a stationary state or in motion when driving along a bend, for example, by reducing the forces required to return the vehicle to an upright position, in particular as a function of the tilt angle achieved.

[0073] Another advantage of the system according to the invention is that it is easy to return the vehicle to an upright position only when a predetermined tilt angle is reached. In fact, at reduced tilt angles, the shock absorber is not stressed.

[0074] Another advantage of the system according to the invention is that different drive configurations can be easily set up, enabling an adequate selection of the tilt angle beyond which the verticalization effect of the invention occurs.

[0075] The suspension system thus conceived, which is tiltable and steerable during continuous driving, is susceptible to various modifications and variations within the scope of the inventive concept.

[0076] Moreover, all the details may be replaced by other technically equivalent elements.

[0077] In practice, any materials can be used according to requirements, as long as they are compatible with the specific use, dimensions and possible shapes.

Claims

1. A suspension system (1) for a vehicle (2) which can tilt and steer during continuous driving, the vehicle (2) comprising a chassis (23) and three or more wheels, wherein at least a first wheel (21) and a second wheel (22) are arranged on laterally opposite sides of the vehicle (2), the system (1) comprising at least a first support arm (31, 33) and at least a second support arm (32, 34), which are adapted to be hinged to the chassis (23) at their respective inner ends (35) and adapted to rotatably support a first support element (41) of the first wheel (21) and a second support element (42) of the second wheel (22) at their respective outer ends about a steering axis (S41, S42), the system (1) comprising at least a pair of tie rods (51, 53, 52, 54), which are hinged to the first support element (41) and the second support element (42) at their outer ends (55, 56), respectively, and are hinged to each other at their inner ends (57), wherein The system (1) comprises a shock absorber (7) which is hinged to the chassis (23) at a first end (70), a pair of connecting rods (81, 82) which are hinged to each other at their inner ends and to a second end (71) of the shock absorber (7) which is opposite to the first end (70), the pair of connecting rods (81, 82) being hinged to a portion of the first support arm (31, 33) and a portion of the second support arm (32, 34) at their outer ends, respectively, and at least one abutment element (91, 92) which is configured to abut against the first support arm (31, 33) or the second support arm (32, 34) respectively, thereby preventing the possibility of rotation around respective hinge restraints (C31, C32) present in their respective inner ends exceeding a predetermined rotation angle associated with a first tilt angle (α) of the vehicle (2).

2. The system (1) according to claim 1, wherein: The shock absorber (7) is configured to compress a portion only when the vehicle (2) is tilted at an angle greater than the first tilt angle (α) associated with the predetermined rotation angle.

3. The system (1) according to claim 1 or 2 comprises a pair of elastic end stop elements (110, 111), which are designed to feedback the respective abutting elements (51, 52, 53, 54) of the system (1) when the vehicle (2) is tilted at a maximum tilt angle (β) greater than the first tilt angle (α).

4. The system (1) according to claim 1 or 2, wherein: The at least one abutment element (91, 92) comprises a pair of abutment elements, and the first support arm (31, 33) or the second support arm (32, 34) can abut against outer surfaces (910, 920) of the abutment elements.

5. The system (1) according to claim 4, wherein: The pair of abutment elements (91, 92) can be selected from a group including at least two pairs of abutment elements, wherein the total occupied area of ​​the abutment elements in the first pair of abutment elements is different from the total occupied area of ​​the abutment elements in the second pair of abutment elements, so as to increase or decrease the rotation angle allowed by the first support arm (31, 33) and / or the second support arm (32, 34) before hitting one of the two abutment elements.

6. The system (1) according to claim 4, wherein: The pair of abutment elements (91, 92) are made of elastic material and can be selected from a group including at least two pairs of abutment elements, wherein the elastic coefficient of the elastic material of the abutment elements in the first pair of abutment elements is different from the elastic coefficient of the material of the abutment elements in the second pair of abutment elements.

7. System (1) according to any one of the preceding claims, wherein: The at least one abutment element (91, 92) comprises a pair of cylinders, wherein the first support arm (31, 33) or the second support arm (32, 34) is adapted to abut against a lateral cylindrical surface (910, 920) of the cylinders.

8. The system (1) according to claim 7, wherein: The pair of cylinders may be selected from a group comprising at least two pairs of cylinders, wherein a base circular diameter over the length of a cylinder in a first pair of cylinders is different from a base circular diameter over the length of a cylinder in a second pair of cylinders.

9. System (1) according to claim 7 or 8, wherein: The pair of cylinders is made of an elastic material and is selectable within the group comprising at least two pairs of cylinders, wherein the elastic coefficient of the elastic material of the cylinders of a first pair of cylinders is different from the elastic coefficient of the material of the cylinders of a second pair of cylinders.

10. A vehicle (2) comprising a chassis (23) and three or more wheels, wherein at least one first wheel (21) and one second wheel (22) are arranged on laterally opposite sides of the vehicle (2), respectively, characterized in that A suspension system (1) comprising a tiltable and steerable suspension system during continuous driving according to one or more of the preceding claims.

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