FR3109923A1 - Self-propelled vehicle for handling, in particular semi-trailers - Google Patents

Abstract

The invention relates to a self-propelled vehicle (1) for handling in particular semi-trailers. It comprises a frame (2) carried by a front steering axle (5), provided with two motorized twin wheels (3), and a rear axle (6) provided with two free wheels (4). These axles (5, 6) are coupled to jacks (11, 16) arranged to modify the spatial position of the frame (2) relative to the ground (S). It further comprises a fifth wheel (20) integral with the frame (2) and arranged to hook onto the kingpin (21) of a semi-trailer (22). The spatial position of the fifth wheel (20) relative to said kingpin (21) is determined by the spatial position of said frame (2). The vehicle (1) further comprises locking means arranged to block the kingpin (21) hooked into the fifth wheel (20) when said vehicle and said semi-trailer are coupled, and remove the articulation between said vehicle and said semi-trailer to the right of said kingpin to obtain a compact and one-piece convoy which can be piloted remotely or independently. The rear axle (6) allows the wheels (4) to be retracted from the ground so that the convoy is only steered by the front axle (5). Figure for the abstract: Fig 7.

Description

Self-propelled vehicle for handling, in particular, semi-trailers

The present invention relates to a self-propelled vehicle for the handling in particular of semi-trailers, said vehicle comprising a chassis, rolling means, a cockpit, a fifth wheel arranged to hook onto the coupling pin of the semi-trailer and means for adjusting the spatial position of said fifth wheel relative to said coupling pin.

This type of vehicle, also called "fleet tractors", is generally used outside the road network and more specifically on logistics or industrial sites to handle, move from one dock to another, semi-trailers other than with using the thermal tractor of the semi-trailer truck. The primary interest of these fleet tractors is an economic interest since it avoids immobilizing thermal tractors and their drivers for handling operations. The second interest is an ecological interest since it avoids having to use heat engines for handling operations when the fleet tractors are electric or so-called clean vehicles.

Several park tractor solutions have been developed to meet these needs:
- terminal tractors operated for port handling,
- specific tractors with the same architecture as standard thermal tractors, but with an electric battery-powered traction chain,
- remote-controlled self-propelled vehicles that look like standard tractors, but without a driver's cab, and
- forklifts equipped with a fifth wheel fixed to the forks.

Several examples are described in the publications DE 102018008007 A1, WO 2019243573 A1, DE 102015010749 A1, EP 2470410 B1, EP 2231464 B1, WO 200/19328 A1, EP 1366971 B1, EP 1294609 B1, US 463902517 FR4.

All these solutions have drawbacks which limit their distribution, such as high acquisition costs, problems with legislation with regard to a compulsory driving license for some, problems of congestion which lengthens the convoy, driving difficulties of these vehicles for non-road handlers mainly due to the complicated reverse gears because the convoy is articulated and to the reduced turning radii to limit the space for movement. In addition to these drawbacks, there is the unavailability of electric vehicles in the event of battery recharging and maintenance operations, as well as the impossibility of transforming an articulated convoy into an autonomously guided convoy (AGV - Automated Guided Vehicles). Indeed, the presence of an articulation between the fleet tractor and the semi-trailer introduces into the convoy an uncontrolled degree of freedom and a non-monotrack trajectory which makes its autonomous piloting impossible without a pilot.

The present invention aims to overcome these drawbacks by proposing a new generation self-propelled vehicle, designed to eliminate the articulation between said vehicle and the semi-trailer to be handled, and create a compact and one-piece convoy allowing said convoy to be piloted autonomously, unmanned, said vehicle being of simple, compact, reliable, secure, eco-responsible, ergonomic design, representing a competitive investment, offering great flexibility of use, and thus being able to be widely distributed in very varied fields of application. It is also easily adaptable and transformable for any other compatible handling operation.

For this purpose, the invention relates to a vehicle of the type indicated in the preamble, characterized in that it further comprises locking means arranged to lock the coupling pin hooked into the fifth wheel when said vehicle and said semi-trailer are hitched, and eliminate the articulation between said vehicle and said semi-trailer in line with said coupling pin to obtain a compact and one-piece convoy.

In a preferred form of the invention, said locking means comprise two crosspieces, including a front crosspiece and a rear crosspiece, arranged on the frame on either side of said fifth wheel, and arranged to form a support surface which comes into contact with the underside of the semi-trailer when said coupling pin is hooked into the fifth wheel, and transferring the weight of the front of the semi-trailer from said fifth wheel onto said front and rear crossmembers.

At least said rear cross member can be coupled to an actuator to be movable between a passive position in which it is lowered below the level of said fifth wheel and authorizes coupling between the vehicle and the semi-trailer, and an active position in which it is raised above the level of said fifth wheel and locks said hitch.

Said rolling means advantageously comprise at least one front wheel and two rear wheels carried respectively by a front axle and at least one rear axle, said front and rear axles being coupled to actuators arranged to modify the spatial position of said chassis relative to the ground .

In the preferred form of the invention, said fifth wheel is secured to said chassis and said front and rear axles and their actuators constitute means for adjusting the spatial position of said fifth wheel relative to a semi-trailer.

Said front axle may consist of a compass formed by a lower branch and an upper branch articulated around a transverse pivot axis, the free end of said lower branch carrying said at least one front wheel, and the the free end of said upper branch being coupled to said frame. In this case, said front axle advantageously comprises an actuator extending between said lower and upper branches in a plane of symmetry of said vehicle, and arranged to modify the opening angle of said compass modifying the height of said chassis relative to the ground.

Said front axle may further include a steering column coupled to an actuator to be rotatable about an axis of rotation situated in a plane of symmetry of said vehicle, to orient said front axle with respect to said plane of symmetry and to ensure the direction of said vehicle.

Said rolling means advantageously comprise two twin front wheels, carried by the same front axle. And said engine may comprise at least one motor coupled to said at least one front wheel. It can thus comprise one motor per wheel.

Said at least one rear axle may comprise a lever arm articulated on said frame around a pivot axis, carrying at its free end at least one of said rear wheels, and coupled to an actuator arranged to modify the height of the frame relative on the ground, and moving said at least one rear wheel between a low position in which said wheel is in contact with the ground and a high position in which said wheel is retracted with respect to the ground.

In the preferred embodiment, said rear wheels are freewheels, independent of each other, and each mounted on a rear axle.

Said vehicle may advantageously include safety means arranged to prevent accidental pivoting of said vehicle relative to said semi-trailer when they are hitched. They may comprise at least two safety jaws located laterally on either side of said frame and coupled to at least one actuator arranged to move them between a passive position in which they are distant from each other and allow the passage of said vehicle under said semi-trailer, and an active position in which they are close together and adjust to the width of said semi-trailer.

Said safety jaws may further comprise position sensors arranged to deliver information on their exact position when said vehicle and said semi-trailer are hitched in order to correct, if necessary, the directional angle of the front axle to align the plane of symmetry of said vehicle with the longitudinal axis of the semi-trailer.

Said cockpit may comprise, according to the variant embodiments, at least one item of equipment chosen from the group comprising a remote control for piloting said vehicle from the ground, a platform provided with a control console, a closed cabin provided with a driving position , an electronic control unit to guide said vehicle autonomously.

Preferably, said vehicle comprises studs forming feet on which said vehicle rests on the ground when said chassis is in the lowered position.

In said preferred embodiment, said vehicle may comprise at least one power compartment and/or one technical compartment attached to said chassis in a removable manner to be interchangeable with at least one other power compartment and/or one technical compartment.

Said at least one power compartment and/or a technical compartment can be fixed to said chassis by quick-fixing means allowing said compartment to be removed and raised automatically. And said power compartment can advantageously include rechargeable batteries.

Said studs can be arranged under said at least one power compartment and/or a technical compartment.

Said vehicle may also comprise accessories chosen from the group comprising a trailer hitch allowing said vehicle to handle a trailer equipped with a drawbar, a pallet-tray equipped with feet and a coupling pin allowing said vehicle to handle goods stored on said pallet-tray, a special chassis equipped with a mast and forks allowing said vehicle to handle pallets.

The present invention and its advantages will appear better in the following description of several embodiments given by way of non-limiting examples, with reference to the appended drawings, in which:

Figure 1 is a perspective view from above of a self-propelled vehicle according to the invention,

Figure 2 is a perspective view from below of the vehicle of Figure 1,

Figure 3 is a top view of the vehicle of Figure 1,

Figure 4 is a bottom view of the vehicle of Figure 1,

Figure 5 is a front view of the vehicle of Figure 1 and a semi-trailer of which only the front part is illustrated, showing the convoy in the before hitching position,

Figure 6 is a front view similar to Figure 4 showing the convoy in the hitched position,

figure 7 is a front view similar to figure 5, showing the convoy in transport position,

Figure 8 is a perspective view of the self-propelled vehicle of Figure 1 in the transported position in a semi-trailer on one side and in the position hitched to the semi-trailer on the other side,

Figure 9 is a perspective view of the vehicle of Figure 1 in the position hitched to a trailer,

Figure 10 is a perspective view of the vehicle of Figure 1 equipped with a platform for transporting pallets, and

Figure 11 is a perspective view of the vehicle of Figure 1 equipped with forks to transport a pallet.

In the embodiments illustrated, the identical elements or parts bear the same reference numbers. Also, terms that have a relative meaning, such as vertical, horizontal, right, left, front, back, above, below, etc. must be interpreted under normal conditions of use of the invention, and as represented in the figures.

Referring to Figures 1 to 4, the self-propelled vehicle 1 according to the invention comprises a frame 2 taking the form of a plate, and carried by rolling means, consisting of at least three wheels 3, 4, of which at least a front wheel 3 and two rear wheels 4. In the example shown, the rolling means comprise four wheels 3, 4, including two twin front wheels 3 carried by a front axle 5 and two rear wheels 4 carried by at least one rear axle 6. This example is of course not not limiting and the number of wheels may vary depending on the specifications.

The 5 front axle has two twin 3 front wheels. They are carried by the same transverse axis 7 pivoting freely about an axial axis coinciding with the plane of symmetry A of said vehicle 1. The transverse axis 7 performs the function of a lifter, equivalent to a four-wheeled vehicle, allowing ensure the isostatism of the four wheels of said vehicle 1 whatever the surface of the ground S. The front axle 5 comprises a compass oriented in the plane of symmetry A of the vehicle 1 and consisting of a free lower branch 8 and a upper branch 9 coupled to the frame 2, the lower branch 8 carrying the transverse axis 7 of the twin wheels 3. The two branches 8 and 9 of the compass are articulated around a transverse pivot axis 10, parallel to the transverse axis 7 of the wheels 3. They are also coupled to an actuator, such as a compass cylinder 11 which is extends along an axis B between the two branches 8 and 9. This compass actuator 11 can be hydraulic, pneumatic or electric. The movements of the compass cylinder 11 make it possible to modify the opening angle between the arms 8 and 9 of the compass, by causing them to pivot around the pivot axis 10. By pivoting in one direction or another, the arm lower 8 which takes the twin wheels 3 with it, causes the chassis 2 to rise or lower with respect to the ground S. The front axle 5 also comprises another actuator, such as a steering cylinder 12 connected to the chassis 2 and to the upper branch 9 of the compass via a steering column 13, movable around an axis of rotation C located in the plane of symmetry A of the vehicle 1. The steering column 13 comprises a crank 13a coupled to said steering cylinder 12 so that its point of application C′ is off-center relative to the axis of rotation C. The steering cylinder 12 can be hydraulic, pneumatic or electric, and extends in a horizontal plane. Its function is to orient the front axle 5 with respect to the plane of symmetry A of the vehicle 1 and thus to ensure the direction of the said self-propelled vehicle 1. Of course, any other type of actuator may be suitable. It is possible, for example, to replace the steering cylinder 12 with a rack and pinion motor system to increase the steering angle by + or – 90° and thus improve the maneuverability of the vehicle 1.

The rear axle 6 comprises two rear wheels 4, spaced apart from each other forming with the two paired front wheels 3 a triangle. In the example shown, the wheels 4 are free and independent of one another. In this case, the rear axle 6 is split into two independent half-axles. Of course, these wheels 4 could be linked and carried by a single rear axle 6. In the rest of the description, the rear axle 6 in the singular designates both a single axle or two independent axles or half-axles. In the example shown, the wheels 4 are each mounted on a lever arm 14, articulated on the frame 2 around a pivot axis 15 and coupled to an actuator such as a lifting cylinder 16. The lifting cylinder 16 which can be hydraulic, pneumatic or electric, is connected between the frame 2 and the lever arm 14 at a point of application D off-center with respect to the pivot axis 15. The movements of the lifting cylinder 16 control the pivoting of the lever arm 14 around its pivot axis 15. By pivoting in one direction or another, the lever arm 14 which carries one of the wheels 4, makes it possible both to adjust the height of the frame 2 relative to the ground S, and to move said wheel 4 between two extreme positions, namely a low position in which the wheel 4 is in contact with the ground S, and a high position in which the wheel 4 is retracted with respect to the ground S. lifting 14 of the two wheels 4 can be synchronized according to the functions of e adjustment or lifting to be carried out. Any other means of lifting and/or controlling the lifting of the wheels 4 of the rear axle 6 may be suitable. The control of the lifting cylinders 16 can be slaved to the control of the compass cylinder 11 to modify the height of the frame 2 parallel to itself. The rear axle 6 can be equipped with a brake, for example with pneumatic or hydraulic control, or any similar braking system, depending on the needs and the specifications of the vehicle 1.

The design of the front 5 and rear 6 axles makes it possible to act on the spatial position of the chassis 2 of the vehicle 1 since it can go up and down, tilt to the left and to the right, and tilt forwards and the rear according to the height adjustment of the front wheels 3 and each of the rear wheels 4. These different possibilities of movement provide said vehicle 1 with flexibility of adaptation and new functions as explained later in the context of its operation.

The self-propelled vehicle 1 according to the invention is propelled by a motorization which may comprise at least one motor 17. It may be a hydraulic motor associated or not with a reduction gear. In this case, the hydraulic power is provided by a heat engine. Preferably, it may be an electric motor associated or not with a reduction gear. In this case, electrical energy is supplied either by batteries or by a hydrogen fuel cell. Of course, these examples are not limiting and any type of motor may be suitable. For obvious environmental reasons, one or more non-polluting engines 17 will be chosen, i.e. without greenhouse gas (GHG) emissions. In the example shown, the front wheels 3 are fixed directly to the output shaft of an electric motor 17. Two coaxial electric motors 17 can be provided, one motor for each of the wheels 3. In this case, the motors 17 are synchronized or slaved to each other. The motors 17 drive the wheels 3 in rotation either in one direction or the other to move the vehicle 1 either forwards or backwards, and the steering cylinder 12 steers said vehicle. The vehicle 1 comprises in known manner a brake (not shown), such as a parking brake which locks the front wheels 3 for example.

The vehicle 1 further comprises a power compartment 18 preferably fixed under the chassis 2, in the rear part, and arranged to supply the motor or motors 17 with energy. If it is an electric motor 17, then the power compartment 18 comprises a set of rechargeable electric batteries or a fuel cell and a hydrogen tank. If it is a hydraulic motor 17, then the power compartment 18 includes a heat engine and a hydraulic circuit coupled to said hydraulic motor 17. The vehicle 1 can also comprise one or more technical compartments 19 preferably fixed under the chassis 2, in the front part, to house auxiliary equipment, such as: electrical cabinet, oil accumulator, radiator, single battery, air compressor tablet, etc., this list not being exhaustive. Of course, any other arrangement of said compartments 18 and/or 19 may be suitable.

The self-propelled vehicle 1 of the invention comprises, on the upper part of the chassis 2, a coupling platform, called in the following description a fifth wheel 20, known per se, in which the coupling pin is hooked 21 of a semi-trailer 22 (Fig. 5). In the example shown, the fifth wheel 20 is preferably positioned between the front 5 and rear 6 axles. The vehicle 1 further comprises means for locking the coupling pin 21 hooked into the fifth wheel 20. They consist of a front cross member 23 and a rear cross member 24 arranged on either side of the fifth wheel 20, which extend parallel over all or part of the width of the frame 2. These front 23 and rear 24 cross members form a bearing surface having the function of coming into contact with the underside 25 of the semi-trailer 22 when its coupling pin 21 is hooked into the fifth wheel 20. Thus, they make it possible to transfer the weight of the front of the semi-trailer 22 from the fifth wheel 20 on said chassis 2, and to simultaneously eliminate the articulation formed by the coupling pin 21 in the fifth wheel 20. The semi-trailer 22 may include a sliding plate 25 which covers its underside and facilitates sliding on harness 20 hangs before hitching operations. The front 23 and rear 24 crosspieces may comprise pads 23', 24' made of materials with a high coefficient of friction of the polymer type or having a highly rough surface, to adhere to the sliding plate 25 when the operation of coupling is completed as explained later. Of course, any other form of technically equivalent locking means may be suitable, such as columns or a support frame arranged around the fifth wheel 20. The crosspieces 23 and 24 have the advantage of extending transversely under the semi- trailer 22, to bear on its longitudinal members and to ensure flat contact avoiding any risk of punching in the event of support not positioned under said longitudinal members.

The rear crossmember 24 is also coupled to an actuator making it possible to modify the height of this rear crossmember 24 relative to the chassis 2 and to the fifth wheel 20. In the example shown, the actuator is constituted by the lifting cylinder or cylinders 16 of the rear axle 6 controlling, via a cam or any other transmission member and in a combined manner, the lifting of the rear crossmember 24 when the wheels 4 are raised in the retracted position. In a variant not shown, it may consist of one or two load cylinders housed in or under the rear crossmember 24. In this case, they may be controlled by the control of the lifting cylinder or cylinders 16 to perform a movement combined. This rear crossmember 24 can thus adopt a passive position in which it is lowered below the level of the fifth wheel 20 and authorizes coupling, and an active position in which it is raised above the level of the fifth wheel 20 and locks the coupling. The movement between these two positions can be a few centimeters.

The vehicle 1 further comprises safety means to prevent the accidental pivoting of the self-propelled vehicle 1 under the lower plate 21 of the semi-trailer 22, when it is hitched. They consist of at least two safety jaws 27 arranged laterally on either side of the frame 2. They are oriented vertically and are arranged parallel to each other. They are coupled to at least one actuator, and are in the example shown each coupled to a safety cylinder 28 via rods 29 forming a deformable parallelogram. They are therefore mobile in parallel planes, between a passive position in which they are distant from each other and allow the passage of the vehicle 1 under the semi-trailer 22, and an active position in which they are close one from the other and adjust to the width of the semi-trailer 22 when the vehicle 1 is hitched, resting on its side faces. The passive position can advantageously be contained within the overall dimensions of the vehicle 1 so that the safety jaws 27 do not exceed the width of the chassis 2 and the vehicle 1 thus remains within the transport gauge of a semi-trailer 22 standard (see FIG. 8). The safety jaws 27 can be made of or coated with a flexible material that is not mechanically aggressive for the edges of the side faces of the semi-trailer 22, such as for example a neoprene or the like.

In addition, the safety jaws 27 can be instrumented by position sensors or the like, to have information on their exact position in order to know the value of the possible angular offset which has formed between the longitudinal axis of the semi-trailer 22 and the plane of symmetry A of the vehicle 1 at the end of the coupling operation. This information makes it possible to correct by a software tool the directional angle of the front axle 5 via the steering cylinder 12 to obtain the zero degree position corresponding to a perfect alignment between the vehicle 1 and the semi-trailer 22.

The vehicle 1 is further equipped with a cockpit such as a platform 30 located at the front of the chassis 2, cantilevered to accommodate an operator. Preferably, it is designed to be easily removable to be completely removed when the vehicle 1 is guided autonomously (AGV) or to be replaced by a comfortable closed cabin. The platform 30 is secured by a guardrail 31. Access is provided by a staircase 32. A control panel 33 is installed on the platform 30 to allow the operator to control said vehicle 1. This control panel 33 can be supplemented or replaced by a radio-controlled remote control making it possible to control said vehicle 1 from the ground S by an operator. This control from the ground makes it possible to ensure the correct movements of the semi-trailer 22, in particular when it has to be positioned in front of a loading dock in reverse.

As an option, the vehicle 1 can be guided autonomously (AGV). It then integrates an electronic control unit which will control the vehicle 1 in place of the operator by computer means, ground guidance, laser beams, a GPS-type geolocation system, and any other known and future means. In this case, the platform 30 can be limited to giving access to the operator to ensure the connection of the connectors 34 to the semi-trailer 22. It can also be dismantled from the chassis 2, making it possible to reduce the length of said vehicle 1. Thus , it fits perfectly under the semi-trailer 22 without protruding or protruding by a negligible length. Under these conditions, it does not increase the size of the semi-trailer 22, and facilitates its maneuvers in narrow maneuvering areas.

The vehicle 1 also includes other equipment useful for its operation, such as electrical and pneumatic connectors 34 provided at the front of the chassis 2 to connect the electrical and pneumatic circuits of the semi-trailer 22 to said vehicle 1, and studs 35 provided under the power 18 and technical compartments 19 to form feet on which the vehicle 1 rests on the ground when it is at rest and its frame 2 is lowered and the wheels 3 and 4 retracted.

It can also be equipped with accessories allowing it to be used for other handling functions, such as those illustrated in figures 9 to 11 and described later. In addition, its particularly compact design allows it to be transported in a semi-trailer 22 as illustrated in Figure 8.

Functioning :

When the vehicle 1 is in the rest position, that is to say stationary, the frame 2 can rest on the ground S on the studs 35. In this position, not shown, the frame 2 is lowered respectively via the cylinder compass 11 and the lifting cylinder 16. This rest position ensures the stability of the vehicle 1, especially in the event of failure of the hydraulic circuits or cylinders.

To start the vehicle 1 in order to initiate a maneuver, the operator can either climb on the bridge 30 by the staircase 32 to access the control panel 33, or remain on the ground S equipped with a remote control (not shown ). He raises the chassis 2 by actuating the corresponding compass 11 and lifting cylinders 16 and starts the motor or motors 17. He moves the vehicle 1 forward by rotating the motors 17 and directing the front axle 5 via the cylinder steering 12 to steer vehicle 1.

The operator presents the vehicle 1 on the side of the coupling of the semi-trailer 22 (fig.5), the front wheels 3 being positioned in alignment with the semi-trailer 22. He adjusts the height and the inclination of the fifth wheel 20 by acting on the compass 11 and lifting cylinders 16 in a combined or differentiated manner, in particular if the attitude of said chassis 2 has to be corrected. The fifth wheel 20 must be at the height of the sliding plate 25 provided under the semi-trailer 22. It moves back according to the rear arrow then the vehicle 1 under the chassis of the semi-trailer 22 until the coupling pin 21 engages and locks automatically in the corresponding housing of the fifth wheel 20 (fig. 6).

Then the operator actuates the compass jack 11 to raise the frame 2 and put the front crosspiece 23 in contact with the sliding plate 25. Then, he actuates the lifting jacks 16 to raise the rear wheels 4 according to the arrow R which leave the ground S and place themselves in the retracted position (fig. 7). Together the lifting cylinders 16 push the crosspiece 24 upwards according to the arrow L against the sliding plate 25 (fig. 7). In response, the fifth wheel 20 exerts a pulling force downwards on the coupling pin 21. In this position, it is no longer the fifth wheel 20 which carries the front of the semi-trailer 22, but the crosspieces 23 and 24. The semi-trailer 22 then becomes integral with the vehicle 1 thanks to the friction of the pads 23', 24' on the sliding plate 25. The coupling pin 21 becomes a prisoner of the fifth wheel 20 and no longer has any degree of freedom. Under these conditions, the articulation between the vehicle 1 and the semi-trailer 22 in line with the coupling pin 21 is completely eliminated. A compact and one-piece convoy is obtained.

For safety, the operator presses the two safety jaws 27 via the safety cylinders 28, against the side faces of the semi-trailer 22. They prevent accidental sliding of the pads 23', 24' with respect to the sliding plate 25. Thus, vehicle 1 remains in line with semi-trailer 22.

The vehicle 1 only rests on its front wheels 3.

The operator then lifts the frame 2 via the compass jack 11 to raise the supports 36 of the semi-trailer 22 from the ground S sufficiently so as not to interfere with the transport.

From this moment, all the weight of the vehicle 1 and that of the front of the semi-trailer 22 rests on the two front wheels 3. The operator can move the convoy as if it were a standard straight truck. The convoy is compact and one-piece since it is no longer articulated as with existing solutions. This unique advantage compared to all other known solutions greatly facilitates the piloting and maneuvering of the convoy. It also makes it possible to transform it into an autonomously guided convoy (AGV).

The design trick which consists in positioning the axis of rotation B of the front axle 5 at the front of the fifth wheel 20 makes it possible to reduce the vertical force on the said front axle 5 and therefore on the wheels 3. This arrangement also makes it possible to free up more space for housing equipment at the rear of the vehicle 1, such as accessories to add functionality to it (see FIGS. 9 to 11).

Charging the batteries:

If the vehicle 1 is equipped with electric motors 17, then the batteries contained in the power compartment 18 should be regularly recharged. profitability. The invention also makes it possible to overcome this drawback by providing a removable power compartment 18 to be interchangeable with another identical power compartment 18 but whose batteries have been recharged in masked time. Indeed, it is known that the batteries can be removable and replaceable to avoid wasting time on recharging. To do this operation, it is generally necessary to have an external handling system to perform this replacement. However, the vehicle 1 is advantageously equipped with a semi-automatic interchangeability function which is carried out without tools or even without an operator. For this purpose, the power compartment 18 is assembled to the frame 2 by a quick-release device 37, such as for example pins which fit vertically into slots in the frame 2 or any other equivalent system. Furthermore, it is electrically connected to frame 2 by an electric cable 38 and a socket 39 (FIG. 3).

To change its discharged 18 power compartment, vehicle 1 places itself next to a recharged 18 power compartment. Going down the chassis 2, he places the compartment 18 on the ground S on its studs 35. During this maneuver, the quick-release device 37 mechanically and automatically releases the power compartment 18, which remains electrically connected to the chassis 2 by the cable electric 38 and socket 39.

The vehicle 1 goes up its chassis 2 then moves forward to emerge from the unloaded power compartment 18 which is still connected. It then shifts to present itself above the reloaded power compartment 18 . It lowers the frame 2 and its quick-release device 37 automatically locks the reloaded power compartment 18. The operator stops the vehicle 1. He disconnects the plug 39 from the discharged power compartment 18 to reconnect it to the recharged power compartment 18. Of course, the electric cable 38 is long enough to perform the maneuver. Vehicle 1 is operational again after only a few minutes and without the use of any external tools.

Maintenance operations:

Work on wheels 3 and 4 as well as on the front 5 and rear 6 axles can be carried out without a lift or jack. It suffices for this to lower the frame 2 to place the studs 35 on the ground S, to lift the wheels 3 and 4 and to secure the corresponding joints at their pivot axes 11 and 15 by a chain or any other equivalent means.

The interventions on the technical compartment 19 can be carried out in masked time as for the recharging of the batteries of the power compartment 18. In this case, the defective technical compartment 19, fixed in a removable manner on the frame 2 by a quick fastening device, can be replaced quickly with a technical compartment 19 revised and in perfect working order. At the same time, the defective technical compartment 19 can be overhauled and repaired without wasting time or immobilizing the vehicle 1.

Other uses of the self-propelled vehicle 1 according to the invention:

To improve the profitability of a vehicle 1 which does not have a load factor of 100%, it can be assigned to other functions, such as those listed below and given by way of non-limiting examples.

a) The handling of trailers 41 of carrying tractors (fig. 9). In this case, the rear of the vehicle 1 must be equipped with a trailer hitch 40 of a known type compatible with the drawbar 42 of the trailer 41.

b) Handling a pallet-tray (fig. 10). In this case, a special pallet-tray 43 is provided, equipped with feet 44 and a coupling pin (not visible) which is fixed on the fifth wheel 20 of the vehicle 1 and covers the chassis 2. This pallet-tray 43 carries M goods to be moved. The vehicle 1 can attach itself to the loaded pallet-tray 43 resting on the ground S on its feet 44, by slipping underneath. Then he can lift it to move it.

c) Transformation of vehicle 1 into a forklift (fig. 11). In this case, the rear of vehicle 1 is equipped with a special chassis 45 provided at its end with a vertical mast 46 carrying forks 47. To lift a pallet 48, there are two options. If you want to move the pallets 48, it suffices to lift the chassis 2 of the vehicle 1 using the compass 11 and lifting cylinders 16. On the other hand, if you want to stack the pallets 48 to load and/or unload a semi - trailer 22 for example, the vertical mast 46 will be replaced by a lifting mast (not shown) as on a conventional forklift.

The vehicle 1 has a width less than a semi-trailer platform 22, which allows it to be installed at the rear of the semi-trailer 22. A pallet-platform 43 can be added to it above said vehicle 1 , to optimize the loading of the semi-trailer 22 by installing goods M on the pallet-tray 43. In the transport position, the wheels 3 and 4 are raised and it rests stably on its chassis 2 via the studs 35, thus guaranteeing greater safety. Given its low overall height, two vehicles 1 can be transported one above the other. In addition, the pallet-tray 43 described above can be positioned in a semi-trailer 22 to create an additional loading stage. Thus, it becomes possible on delivery to unload a lower pallet without moving the pallet-tray 43.

The present invention is of course not limited to the embodiments described but extends to any modification and variant obvious to a person skilled in the art within the limits of the appended claims.

Claims (21)

Self-propelled vehicle (1) for handling in particular semi-trailers, said vehicle comprising a chassis (2), rolling means, a cockpit, a fifth wheel (20) arranged to hook onto the coupling pin (21 ) of a semi-trailer (22) and means for adjusting the spatial position of said fifth wheel (20) relative to said coupling pin (21), characterized in that said vehicle further comprises locking means arranged to lock the coupling pin (21) hooked into the fifth wheel (20) when said vehicle and said semi-trailer are hitched, and eliminate the articulation between said vehicle and said semi-trailer in line with said coupling pin to obtain a compact and one-piece convoy. Vehicle according to Claim 1, characterized in that the said locking means comprise two crosspieces, including a front crosspiece (23) and a rear crosspiece (24), arranged on the frame (2) on either side of the said fifth wheel ( 20), and arranged to form a bearing surface which comes into contact with the underside of the semi-trailer (22) when said coupling pin (21) is hooked into the fifth wheel (20), and to transfer the weight from the front of the semi-trailer (22) of said fifth wheel (20) on said front (23) and rear (24) crossmembers. Vehicle according to claim 2, characterized in that at least said rear crossmember (24) is coupled to an actuator to be movable between a passive position in which it is lowered below the level of said fifth wheel (20) and authorizes coupling between the vehicle (1) and the semi-trailer (22), and an active position in which it is raised above the level of said fifth wheel (20) and locks said coupling. 4. Vehicle according to any one of the preceding claims, characterized in that said rolling means comprise at least one front wheel (3) and two rear wheels (4) carried respectively by a front axle (5) and at least one axle. rear (6), and in that said front (5) and rear (6) axles are coupled to actuators arranged to modify the spatial position of said chassis (2) relative to the ground (S). 5. Vehicle according to claim 4, characterized in that said fifth wheel (20) is secured to said chassis (2), and in that said front (5) and rear (6) axles and their actuators constitute means for adjusting the spatial position of said fifth wheel (20) relative to a semi-trailer (22). 6. Vehicle according to claim 4, characterized in that said front axle (5) consists of a compass formed of a lower branch (8) and an upper branch (9) articulated around a pivot axis (10) transversely, the free end of said lower branch (8) carrying said at least one front wheel (3), and the free end of said upper branch (9) being coupled to said frame (2), and in that that said front axle (5) comprises an actuator extending between said lower (8) and upper (9) branches, and arranged to modify the opening angle of said compass modifying the height of said chassis (2) with respect to the ground (S). 7. Vehicle according to any one of claims 4 to 6, characterized in that said front axle (5) further comprises a steering column (13) coupled to an actuator to be rotatable around an axis of rotation (C) located in a plane of symmetry (A) of said vehicle, orienting said front axle (5) with respect to said plane of symmetry (A) and steering said vehicle (1). 8. Vehicle according to claim 4, characterized in that said rolling means comprise two twin front wheels (3), carried by the same front axle (5). 9. Vehicle according to any one of the preceding claims, characterized in that said engine comprises at least one motor (17) coupled to said at least one wheel (3) before. 10. Vehicle according to claim 4, characterized in that said at least one rear axle (6) comprises a lever arm (14) articulated on said frame (2) about a pivot axis (15), carrying at its free end at least one of the rear wheels (4), and coupled to an actuator arranged to modify the height of said frame (2) relative to the ground (S), and to move said at least one rear wheel (4) between a low position in which said wheel (4) is in contact with the ground (S) and a high position in which said wheel (4) is retracted with respect to the ground (S). 11. Vehicle according to any one of claims 5 to 10, characterized in that said rear wheels (4) are freewheels, independent of one another, and each mounted on a rear axle (6). 12. Vehicle according to any one of the preceding claims, characterized in that it comprises safety means arranged to prevent accidental pivoting of said vehicle (1) relative to said semi-trailer (22) when they are hitched. 13. Vehicle according to claim 12, characterized in that said safety means comprise at least two safety jaws (27) located laterally on either side of said frame (2) and coupled to at least one actuator arranged to move them. between a passive position in which they are distant from each other and allow said vehicle (1) to pass under said semi-trailer (22), and an active position in which they are close to each other and adjust to the width of said semi-trailer (22). 14. Vehicle according to claim 13, characterized in that said safety jaws (27) comprise position sensors arranged to deliver information on their exact position when said vehicle and said semi-trailer are hitched in order to correct the directional angle of the front axle (5) to align the plane of symmetry (A) of said vehicle with the longitudinal axis of the semi-trailer (22). 15. Vehicle according to any one of the preceding claims, characterized in that said cockpit comprises at least one item of equipment chosen from the group comprising a remote control for controlling said vehicle (1) from the ground (S), a platform (30 ) provided with a control panel (33), a closed cabin provided with a driving position, an electronic control unit to guide said vehicle (1) autonomously. 16. Vehicle according to any one of claims 4 to 15, characterized in that it comprises studs (35) forming feet on which said vehicle (1) rests on the ground (S) when said chassis (2) is in lowered position. 17. Vehicle according to any one of the preceding claims, characterized in that it comprises at least one power compartment (18) and/or one technical compartment (19) fixed to said chassis (2) in a removable manner to be interchangeable with at least one other power compartment (18) and/or a technical compartment (19). Vehicle according to Claim 17, characterized in that the said at least one power compartment (18) and/or one technical compartment (19) is fixed under the said chassis (2) by quick fixing means allowing removal and remounting of the said compartment automatically. 19. Vehicle according to claim 17, characterized in that said power compartment (18) comprises rechargeable batteries. 20. Vehicle according to claim 17, characterized in that said studs (35) are arranged under said at least one power compartment (18) and/or a technical compartment (19). 21. Vehicle according to any one of the preceding claims, characterized in that it comprises accessories chosen from the group comprising a trailer hitch (40) allowing said vehicle (1) to handle a trailer (41) equipped with a drawbar (42), a pallet-tray (43) equipped with feet (44) and a coupling pin allowing said vehicle (1) to handle goods (M), a special chassis (45) equipped with a mast (46) and forks (47) allowing said vehicle (1) to handle pallets (48).