Tricycle vehicle

Abstract

The invention relates to a tricycle vehicle (1) comprising a rear assembly (2), said rear assembly comprising a support frame (44) connected to two wheels (40) of said vehicle (1), and a load chassis (46), said vehicle (1) further comprising a frame (4) configured to allow the installation of a driver of said vehicle (1), said frame (4) being rotationally articulated about an axis of articulation relative to said chassis (46) so as to allow the frame (4) to tilt relative to said rear assembly (2) towards the roadway on either side of a vertical position, said support frame (44) being articulated to said chassis (46) by a ball joint (56) so as to allow simultaneous lifting of both wheels or lifting of only one of said wheels (40), depending on the obstacles encountered. Figure 1

Description

Title of the invention: Tricycle vehicle Technical field of the invention

[0001] The invention relates to a tricycle vehicle, particularly designed to support heavy loads, which is especially useful in delivery services, but also as a simple means of transport, with or without additional cargo. It is, in particular, a motorized tricycle vehicle, especially an electric one. Technical background

[0002] In the field of cycling, two-wheeled cycles of the so-called "scooter" type are already known and appreciated for the riding comfort they provide due to the rider's positioning. However, when it comes to transporting heavy loads, they can prove unsuitable, particularly due to a lack of stability, whether in motion or at a standstill.

[0003] To improve the stability of a cycle, it is known to use a three-wheeled cycle or tricycle. However, these present problems with maneuverability, particularly turning radii.

[0004] Tricycles with a pair of wheels at the front have been proposed and are now commonly used due to their good maneuverability. However, their stability is less than that of a conventional tricycle with a pair of wheels at the rear.

[0005] To improve stability and safety, the front section of conventional tricycles with a pair of rear wheels can tilt relative to the rear section bearing the load, particularly when turning, to prevent the load from causing the vehicle to tip over completely and fall. This could be, for example, a pendulum system allowing articulation between the front and rear of the vehicle.

[0006] However, for vehicles carrying very heavy and / or bulky loads, for example exceeding 100 kg, known pendulum systems are insufficient to ensure safe driving. In particular, they do not allow for easy obstacle clearance or travel on uneven surfaces.

[0007] The invention aims to overcome the aforementioned drawbacks. Summary of the invention

[0008] Thus, the invention relates to a tricycle vehicle comprising a rear assembly, said assembly comprising a support frame, linked to two wheels of said vehicle, and a load chassis, said vehicle further comprising a frame configured to allow the installation of a driver of said vehicle, said frame being articulated in rotation about an articulation axis relative to said chassis so as to allow the frame to tilt relative to said rear assembly in the direction of the roadway on either side of a vertical position, said support frame being articulated on said chassis by a ball joint so as to allow simultaneous lifting of both wheels or lifting of only one of said wheels, depending on the obstacles encountered.

[0009] In this way, we have a vehicle with good stability thanks to its tricycle nature and good maneuverability due to the tilting of the frame relative to the rear assembly.

[0010] Furthermore, the ball joint between the support frame attached to the wheels and the chassis allows movement of the support frame relative to the chassis.

[0011] Thus, the movement allowed by this ball joint located between the support frame linked to the wheels and the chassis ensures that only the support frame part of the crew undergoes a displacement due to the obstacles encountered.

[0012] The vehicle can thus adapt to the terrain on which it travels, in particular to the obstacles to be overcome.

[0013] Indeed, the fact that the two wheels can lift and that this lifting is isolated from the chassis and therefore from the rest of the rear assembly, allows the crossing of obstacles without the entire rear assembly feeling too much jolting.

[0014] Furthermore, thanks to the use of said ball joint, the degrees of freedom offered to this movement will allow the wheels to lift simultaneously, to cross an obstacle crossing the roadway, and independently of each other, to cross an obstacle alongside the roadway such as a bench or a curb.

[0015] According to different embodiments of the invention, which may be taken together or separately:

[0016] - the ball joint connection is achieved via a silent block,

[0017] - the rear assembly includes a rigid bar connecting a first attachment point located on the support frame and a second opposite fixing point located on the chassis,

[0018] - the first fixing point is located near a fixing area of ​​one of the two wheels,

[0019] - the rigid bar is fixed to the support frame by means of a silent block,

[0020] - the rigid bar is fixed to the chassis by means of a silent block,

[0021] - the rigid bar is fixed to the support frame and the chassis via of a silent block,

[0022] - the rigid bar is a Panhard rod,

[0023] - the vehicle, in particular the rear crew, includes a suspension system between the support frame and the chassis,

[0024] - the suspension system is a passive system,

[0025] - the suspension system includes at least one shock absorber,

[0026] - the suspension system comprises two of said shock absorbers,

[0027] - the shock absorbers form an angle with respect to the vertical,

[0028] - each of the shock absorbers is linked to one end of a rigid axle supporting the wheels,

[0029] - the rear assembly includes an anti-roll bar,

[0030] - the anti-roll bar is fixed to each end of the rigid axle,

[0031] - the anti-roll bar is linked to the chassis so that it can work in torsion when Only one of the wheels lifts up.

[0032] - the support frame is U-shaped comprising two arms extending from a central portion connecting the two branches towards a free opposite end,

[0033] - the ball joint is located on the central portion,

[0034] - each of the branches carries one of the ends of the rigid axle,

[0035] - the support frame carries a motor-propulsion unit,

[0036] - the powertrain unit comprises an electric motor,

[0037] - said engine is located at the front or rear of a rear axle of the vehicle. Brief description of the figures

[0038] The invention will be better understood, and other features and advantages thereof will become apparent upon reading the following detailed description, of at least one embodiment of the invention given by way of purely illustrative and non-limiting example, with reference to the accompanying schematic drawings in which:

[0039] - Fig. 1 is a side view of an example embodiment of the tricycle according to the invention;

[0040] - [Fig. 2] is a rear view of an example embodiment of the tricycle conforming to the invention schematically illustrating the tilting of the frame relative to the rear assembly of said tricycle;

[0041] - [Fig. 3] is a rear perspective view illustrating an example of embodiment of part of a rear crew of the tricycle of the [Fig.l];

[0042] - [Fig.4] is a top view of [Fig.3];

[0043] - [Fig. 5] is a perspective view illustrating an example of the realization of a support frame and chassis of the rear crew of the vehicle of the [Fig.1];

[0044] - [Fig. 6] is a rear view illustrating an example of the embodiment of [Fig. 3] in resting position;

[0045] - [Fig. 7] is a rear view illustrating the example embodiment of [Fig. 3] in pour. Detailed description of the invention

[0046] As illustrated in [Fig. 1], the invention relates to a tricycle vehicle 1 comprising a rear assembly 2 and a frame 4 configured to allow the installation of a driver, not illustrated, of said vehicle 1.

[0047] Said frame 4 includes, for example, a frame 6 on which are attached a saddle 8 and a front assembly 10.

[0048] Said front assembly 10 here comprises a steering fork 12, a handlebar 14, and a front wheel 16. The steering fork 12 is rotationally articulated on the frame 4 to allow the front wheel 16 to be steered to the left or right. The handlebar 14 is connected to the fork 12 to allow its orientation by the rider. The front wheel 16 is free to rotate relative to an axle 18 linked to the fork 12. Said front wheel 16 is equipped with a braking system 20, here a disc brake, actuated from the handlebar 14. Said front assembly 10 further includes a front suspension system 22 allowing the transmission to the handlebar 14 and the frame 6 to absorb shocks absorbed by the front wheel 16. This consists, for example, of hydraulic cylinders mounted between the arms of the fork 12 and the axle 18 of the front wheel 16.

[0049] The frame 4 may also include a storage compartment 26. It is located here under the seat 8, which is designed to pivot to provide access to the compartment 26 from above. It is configured to serve as storage for items that the rider needs or wishes to have within easy reach, such as a helmet, first aid kit, manuals, or other items. The compartment 26 is advantageously attached to the frame 6.

[0050] Said frame 4 may also include various bodywork parts, such as a bodywork 28 partially concealing the steering fork 12 and / or a footrest 30. Said bodywork parts are advantageously fixed to said frame 6.

[0051] Said frame 6 preferably has a configuration allowing the vehicle 1 to have a scooter-like appearance, that is to say, allowing the driver to rest his feet in a free space located in front of his torso rather than on pedals located on either side of the frame 4.

[0052] The frame 6 thus has two parallel base arms 32 in a substantially horizontal plane. The base arms 32 support the footrest 30. The frame 6 further comprises a rear arch 34, connecting one end of the base arms 32 and / or supporting, in particular, the saddle 8. It also comprises a front arch 36, connecting the other end of the base arms 32. The front assembly 10 is articulated, for example, on the front arch 36.

[0053] Advantageously, said rear assembly 2 is equipped with a powertrain 38 of said vehicle 1 driving two rear wheels 40, located at a rigid rear axle 39. By providing a pair of wheels located at the rear, a tricycle with favorable stability is obtained.

[0054] Furthermore, as is more particularly illustrated by [Fig. 2], said frame 4 is rotationally articulated relative to said rear assembly 2 so as to permit a The frame 4 can tilt relative to the rear assembly 2 towards the road on either side of a vertical position, as indicated by arrow 41. In other words, the frame 4 can tilt around a pivot axis 42, visible [Fig. 1], supported by the median plane of the rear wheels. Put another way, while the rear assembly 2 remains horizontal, meaning that both rear wheels remain in contact with the road, the frame 4 can tilt, under the effect of an impulse given by the driver, to the right or to the left. Such pivoting gives the vehicle 1 good maneuverability, in particular by allowing the driver to turn without having to turn the handlebar 14, or at least with minimal turning.

[0055] In [Fig. 2], a leftward tilting mechanism for the frame 4 is visible on the left, allowing the rider to turn left, and a rightward tilting mechanism for turning right is visible on the right. Although the vehicle is a tricycle, the rider can thus experience the sensations of riding a two-wheeler. The tilting angle is limited, for example, to 30°.

[0056] For this purpose, said vehicle here includes a tilting joint 58, illustrated [Fig. 1]. Advantageously, said tilting joint 58 includes, for example, a first part or shaft 60, connected to the rear assembly 2 and a second part or bearing (not visible), connected to the frame 4, said bearing being rotationally articulated about said shaft 60. Said shaft 60 and / or said bearing are thus oriented along said articulation axis 42.

[0057] An example of such a tilting joint 58 is described in document FR3020335B1.

[0058] According to the invention, as illustrated in Figures 3 to 5, said rear assembly 2 comprises a support frame 44 connected to the two wheels of said vehicle 1, and a chassis 46 for a load. The frame 4 is rotationally articulated about the articulation axis relative to said chassis 46 so as to allow the frame 4 to tilt relative to said rear assembly 2 in the direction of the roadway on either side of a vertical position.

[0059] The support frame 44 has, for example, a U-shaped or horseshoe-shaped profile, comprising two arms 44a extending from a central portion 44b connecting the two arms 44a to a free opposite end 44c. Said central portion 44b is here trapezoidal in shape and / or said arms 44a are parallel to each other.

[0060] Advantageously, the powertrain 38 is supported by the support frame 44, which gives the vehicle 1 a particularly low center of gravity. The powertrain 38 is housed, in particular, between the two arms 44a of the support frame 44. Each of the arms 44a supports one end of the rear axle 39. The rear axle 39 thus extends perpendicularly from one arm 44a to the other.

[0061] Furthermore, said chassis 46 is advantageously suspended relative to said support frame 44 by means of a suspension system. The transmission of shocks is thus dampened.

[0062] The chassis 46 here includes a load-bearing platform 50. The load-bearing platform 50 is configured to accommodate, for example, a chest 52 or storage box. The load is intended to exceed 100 kg, or even 150 kg. In the case of applications in the field of mail distribution, the chest 52 is intended to contain mail and / or parcels.

[0063] Said support platform 50 is located, for example, to the right of said powertrain 38, above a rear wheel arch 40.

[0064] To accommodate such a load, the rear assembly has a track width greater than 800 mm, or even 900 mm, the track width being defined as the distance between the centers of the contact areas of the wheels of the same axle, measured with the vehicle empty.

[0065] According to the invention, said support frame 44 is articulated on said chassis 46 by a ball joint 56 so as to allow a simultaneous lifting of both wheels or a lifting of only one of said wheels 40, depending on the obstacles encountered.

[0066] The ball joint 56 allows not only the movement of the support frame 44 up and down around an axis perpendicular to the tilting plane, mentioned above, but also its rotation around a longitudinal axis X extending from the front of the vehicle 1 towards the rear.

[0067] We thus have a vehicle 1 exhibiting good stability thanks to its tricycle nature and good maneuverability by tilting the frame 4 relative to the rear assembly 2.

[0068] Furthermore, the ball joint 56 between the support frame 44 linked to the wheels 40 and the chassis 46 allows numerous movements of the support frame 44 relative to the chassis 46.

[0069] Thus, firstly, the movement permitted by this linkage 56 located between the support frame 44 attached to the wheels 40 and the chassis 46 ensures that only the support frame 44 is affected by obstacles encountered. The fact that this lifting is isolated from the chassis 46, and therefore from the rest of the rear assembly 2, allows obstacles to be crossed without the entire rear assembly 2 experiencing excessive shocks.

[0070] In addition, the fact that the two wheels 40 can lift simultaneously or independently of each other, depending on the obstacles encountered, thanks to the choice of a ball joint, makes it possible to maintain good contact with the road while limiting the work of the support frame 44.

[0071] Vehicle 1 can thus adapt to the terrain on which it travels, in particular to the obstacles to be overcome, while maintaining robust chassis.

[0072] The ball joint 56 is located, in particular, between said powertrain 38, in particular the rear axle 39 of said rear assembly 2, and the tilting joint 58.

[0073] The ball joint 56 is obtained here by means of a silent block whose elasticity allows the movement of the support frame 44 up and down, around an axis perpendicular to the tilting plane, mentioned above, and its rotation around the longitudinal axis X. The silent block is located between the support frame 44 and the chassis 46, at the level of the central portion of the support frame 44, preferably said tilting plane.

[0074] The suspension system is located in particular at the rear of the vehicle 1, in particular at the level of the two rear wheels 40.

[0075] Advantageously, the suspension system of the vehicle 1 illustrated here comprises two vertical shock absorbers 62. Preferably, these are hydraulic shock absorbers 62 coupled to a helical spring 64.

[0076] Each of the shock absorbers 62 extends from a lower end connected to one of the ends of the rear axle 39 supporting the two wheels 40 to an upper end connected to the chassis 46, in particular to the load support platform 50.

[0077] The shock absorbers 62 keep the wheels of vehicle 1 in contact with the road and absorb rebounds. The shock absorbers 62 also limit various vibrations. Finally, the shock absorbers 62 also limit body roll and excessive swaying of vehicle 1.

[0078] Advantageously, the suspension system further includes an anti-roll bar 66 fixed to each end of the rear axle 39.

[0079] The anti-roll bar is here a U-shaped metal bar located between the two rear wheels 40. Each end 66a of the anti-roll bar 66 is connected to one end of the rear axle 39, to which the vertical shock absorbers 62 are attached, and the central portion 66b is connected to the chassis 46 so as to work in torsion when the two shock absorbers do not undergo the same deformation. This central portion 66b of the anti-roll bar is, for example, oriented horizontally when unloaded. It is connected to the chassis 46 by one or more bearings, here two, fixed to a lower rear longitudinal member of the chassis 46.

[0080] The anti-roll bar 66, also called a stabilizer bar or anti-roll bar, thus limits the lifting of one wheel relative to the other. In particular, it limits the body roll of vehicle 1 and any potential camber of vehicle 1, especially when cornering. Therefore, the anti-roll bar 66 stiffens the suspension system primarily when cornering, and not when encountering an obstacle.

[0081] Advantageously, the anti-roll bar 66 has elasticity and thus forms a spring between the two wheels 40, thereby improving roll damping.

[0082] By elastically connecting the right and left rear wheels 40, the anti-roll bar 66 reduces the rolling phenomenon.

[0083] Advantageously, the rear assembly includes a rigid bar 68 connecting a first attachment point 70 located on the support frame 44 and a second opposite attachment point 72 located on the chassis 46.

[0084] Preferably, the first fixing point 70 is located near a fixing area of ​​one of the two rear wheels 40 and the second fixing point 72 is located near a fixing area of ​​the other of the two rear wheels 40.

[0085] The rigid bar 68 can be fixed, for example, to the support frame 44 and / or the chassis 46 by means of a rubber bushing. Here, the two ends of the rigid bar 68 are fixed by means of a rubber bushing 74.

[0086] Advantageously, the silent block 74 allows the rigid bar 68 to be held to the support frame 44 and / or the chassis 46 while absorbing shocks and vibrations and preventing them from being transmitted to the rest of the vehicle 1 ensuring driving comfort.

[0087] In the illustrated vehicle 1, the rigid bar 68 is a Panhard bar whose first attachment point 70 is located on a vertical plate 76 of the rear end of the support frame 44 and the second attachment point 72 is located on a vertical rod 78 of the rear end of the chassis 46, in particular a rod 78 linked to the longitudinal member carrying the bearings of the anti-roll bar.

[0088] The rigid bar 68, and more particularly the Panhard bar, makes it possible to stiffen the rear of the vehicle 1 and thus limit the rotation of the support frame 44 around a vertical axis allowed by the ball joint 56.

[0089] As can be seen in [Fig.7], when the vehicle 1 crosses an obstacle at the level of a single rear wheel 40 (here the left rear wheel 40), the support frame 44 tilts from left to right, while the chassis 46 remains horizontal.

[0090] In addition, it is also observed that the chassis 46 pivots thanks to the ball joint 56 and has an angular deviation from the rest position visible in [Fig.6].

[0091] Thus, the ball joint 56 allows an inclination of the support frame 44 around the X axis and an angular inclination around the Z axis which is limited, in particular by the rigid bar 68, here a Panhard rod,

[0092] In order to reduce roll, particularly in the presence of the rigid bar 68, preferably the shock absorbers 62 form an angle with respect to the vertical, particularly when projected onto a plane perpendicular to the longitudinal X axis.

[0093] The angle formed by the shock absorbers with respect to the vertical is between 5° and 10°, preferably on the order of 7°.

[0094] In this way, the shock absorbers 62 can operate in accordance with the rigid bar 68 and its movement.

[0095] Said rear assembly 2 may also include braking systems 80 for the rear wheels 40, in particular disc brakes.

[0096] Said vehicle 1 may also advantageously include a parking brake system, said system being configured to simultaneously block forward and / or backward movement of said vehicle 1 and said tipping.

[0097] Said parking brake system is, for example, manually actuated by means of hydraulic and electrical control. Said hydraulic and electrical control means may include for this purpose a lever, in particular located on the frame 4.

[0098] Advantageously, said frame 4 comprises at least one stop, here two, said vehicle 1 being configured so that said frame 4 comes into contact with said rear assembly 2 via said stops during the tilting of said frame 4. These stops thus define a maximum tilting angle of said frame 4 relative to said rear assembly 2, respectively to the left and to the right. Such contact also prevents the rear assembly 2 from tilting, under the effect of centrifugal force, in a direction opposite to that of the frame 4. The contact of the stops with the rear assembly 2 is made here at a fixed angle, as mentioned above, for example, plus or minus 30°.

[0099] Preferably, the suspension system and / or the roll control system are so-called passive systems. A passive system is understood to be a system in which the dynamic movements of the vehicle 1, for example the relative movement of the support frame and the chassis and / or the roll of the front of the vehicle 1 relative to the rear assembly, are determined by the ground conditions and / or a movement of the driver's body and / or a speed and / or an acceleration of the vehicle 1.

[0100] A passive system is opposed to an active or semi-active system in which the dynamic movements of the vehicle 1 are controlled by at least one on-board system, generally complex, for example based on pumps and / or hydraulic distributors.

[0101] Advantageously, said powertrain 38 includes an engine 82 for driving the vehicle 1. It is located here at the front of the rear axle 39 of the vehicle 1.

[0102] Said motor-propulsion unit 38 is preferably, but not necessarily, electric. In other words, its motor is electric. It may be any type of electric motor, in particular any type of electric motor allowing variable speed control. For example, it may be a machine synchronous. Said machine has a power output of, in particular, between 4 and 10 kW. Although an electric motor presents integration constraints in the type of tricycle according to the invention, it gives vehicle 1 the advantage of being able to operate without consuming hydrocarbons.

[0103] In such a configuration, said motor-propulsion unit 38 further includes, for example, an inverter allowing the motor to be powered from a direct current source and its speed to be varied.

[0104] Said vehicle 1 also includes at least one power supply battery 84 for said power unit 38. These are, for example, batteries having a voltage level greater than 20V, in particular 51V. The battery or batteries are, for example, of the LiFePO4 type.

[0105] Preferably, the battery or batteries 84 are carried by said chassis 46.

[0106] In the illustrated example, the vehicle 1 includes several batteries 84 located in a housing 86 of the chassis 46 situated directly behind the driver, between the powertrain 38 and the rear arch 34 supporting the seat 8.

[0107] The batteries 84 rest in the lower part of the chassis 46, that is to say on a horizontal plane substantially similar to that of the powertrain 38.

[0108] It has been observed that positioning the battery 84 on the rear assembly 2, particularly on a central and lower section thereof, significantly improves the stability of the vehicle 1. Indeed, to power the drive unit, the battery pack has a considerable weight, exceeding 30 kg, or even 60 kg or 90 kg. Its positioning thus plays an important role in the stability of the vehicle 1. The positioning choice indicated above increases the inertia of the rear assembly 2 and prevents it from tipping over, particularly in turns, even at high speeds. This positioning also further improves the mass distribution of the vehicle 1 for good balance and to maintain a low center of gravity, notably without overloading the upper part of the chassis 46 on which the load-bearing platform 50 rests.

[0109] The battery or batteries 84 may also be located partly between the two rear wheels 40 or suspended from said support platform 50, i.e. under said support platform 50, for example near its rear end.

[0110] Other variations of the invention are still possible. For example, the battery may be positioned, in particular at the level of the support frame 44, in a front or rear overhang. It may thus be located either at the front or at the rear of an axle of said rear assembly 2. In this way, a very low center of gravity is maintained for the rear assembly 2.

[0111] Said chassis 46 is, for example, of the welded steel type. It too may be fitted with trim elements 88 intended to conceal at least partially the batteries 84, said support frame 44 and / or said motor propulsion unit 38.

[0112] Said vehicle 1 may also include a charger, intended in particular to recharge the battery 84 supplying the powertrain when the vehicle 1 is stationary. Said charger is intended to be connected, in particular, to a domestic electrical network and / or to a three-phase electrical network.

[0113] Furthermore, said powertrain can be configured to operate in regenerative braking mode. In other words, during braking, it can convert the torque delivered by the wheels into electrical current.

Claims

Claims

1. Tricycle vehicle (1) comprising a rear assembly (2), said assembly comprising a support frame (44), linked to two wheels (40) of said vehicle (1), and a chassis (46) of a load, said vehicle (1) further comprising a frame (4) configured to allow the installation of a driver of said vehicle (1), said frame (4) being articulated in rotation about an articulation axis relative to said chassis (46) so as to allow tilting of the frame (4) relative to said rear assembly (2) in the direction of the roadway on either side of a vertical position, said support frame (44) being articulated on said chassis (46) by a ball joint (56) so as to allow simultaneous lifting of both wheels or lifting of only one of said wheels (40), depending on the obstacles encountered.

2. Vehicle (1) according to the preceding claim, in which the rear assembly comprises a rigid bar (68) connecting a first fixing point (70) located on the support frame (44) and a second opposite fixing point (72) located on the chassis (46).

3. Vehicle (1) according to the preceding claim, in which the rigid bar (68) is fixed to the support frame (44) and / or to the chassis (46) by means of a silentbloc (74).

4. Vehicle (1) according to any one of claims 2 or 3, in which the rigid bar (68) is a Panhard bar.

5. Vehicle (1) according to any one of the preceding claims, wherein the rear assembly is provided with a suspension system between the support frame and the chassis, said suspension system comprising two shock absorbers (62), each of the shock absorbers (62) being linked to one of the two wheels (40).

6. Vehicle according to the preceding claim, in which an anti-roll bar (66) is fixed to each of the two shock absorbers (62).

7. Vehicle (1) according to the preceding claim, in which the anti-roll bar (66) is linked to the chassis (46) so as to be able to work in torsion when only one of the wheels (40) lifts.

8. Vehicle (1) according to any one of claims 5 to 7, wherein the dampers (62) form an angle relative to the vertical.

9. Vehicle (1) according to any one of the preceding claims, wherein the support frame (44) is U-shaped comprising two branches (44a) extending from a central portion (44b) connecting the two branches (44a) towards an opposite free end (44c), the ball joint (56) being located on the central portion (44b) and each of the branches (44a) carrying one of the two wheels (40).

10. Vehicle (1) according to any one of the preceding claims in which the support frame comprises a motor unit (38) equipped with an electric motor (82).

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